Beyond intraocular pressure: introducing a novel glaucoma-specific PROM for evaluating outcomes after IStent inject implantation combined with phacoemulsification cataract surgery

Abstract

This study aimed to develop and validate a glaucoma-specific patient-reported-outcome-measure (PROM) questionary to assess disease-specific burden across all severities of open-angle glaucoma (OAG), including patients undergoing combined IStent inject micro-bypass and cataract surgery. Methods: A cross-sectional, survey-based study was conducted among adults diagnosed with glaucoma, including members of the AGAF (Asociación-Glaucoma para Afectados y Familiares) and patients from two tertiary hospitals who had undergone combined trabecular micro-bypass (TMB) and phacoemulsification surgery. Patients were stratified into mild, moderate, or severe glaucoma groups based on responses to a glaucoma-specific PROM questionnaire. The primary objective was to assess patient perspectives on visual function, quality of life, and treatment satisfaction. Results: A total of 240 participants were included (57.5% female; 58.8% diagnosed > 10 years ago). Most patients (61.7%) had moderate glaucoma. Advanced disease was significantly associated with worse self-perceived visual ability, lower quality of life, increased physical and emotional burden, and decreased satisfaction with treatment (all p < 0.0001). Awareness of glaucoma prior to diagnosis was generally low, but post-diagnosis treatment knowledge was higher among those with milder disease. Functional dependence and socioeconomic impact increased with disease severity. Among TMB-treated patients (n = 35), 97% reported no adverse events or discomfort, and 94.3% expressed confidence in their prognosis. Quality of life and satisfaction post-surgery were high across severity levels. Conclusions: Disease severity and delayed diagnosis negatively affect patients’ experiences and outcomes. Early detection and intervention are critical. Combined cataract and TMB surgery with IStent Inject was associated with high satisfaction and minimal adverse effects within this patient-reported framework.

Supplementary Information

The online version contains supplementary material available at 10.1038/s41598-026-55366-3.

Introduction

Glaucoma is a chronic, progressive optic neuropathy that results in irreversible visual field loss and, if untreated, can ultimately cause blindness^1–3. With an estimated global prevalence affecting over 70 million individuals, approximately 10% of whom are bilaterally blind, glaucoma represents one of the leading causes of irreversible blindness worldwide⁴. Although the disease often begins asymptomatically, it can significantly compromise activities of daily living—such as reading, ambulation, and driving—as the disease advances^4–7. The resulting impairments are associated with increased risks of falls, reduced occupational functioning, and loss of independence^8,9.

Despite its global prevalence, the burden of glaucoma on patients is highly variable and influenced by disease severity, progression, and individual patient contexts. Importantly, primary open-angle glaucoma (POAG), the most common subtype, is often not visually disabling in its mild to moderate stages¹⁰. Standard management in early disease typically centers on pharmacologic and laser-based strategies for intraocular pressure (IOP) reduction^10,11. Surgical intervention has traditionally been reserved for cases exhibiting advanced, rapidly progressing disease or failure to respond to conventional therapies^10,11.

Over the past decade, a paradigm shift has occurred in glaucoma care with the advent of minimally invasive glaucoma surgeries (MIGS), offering earlier-stage surgical alternatives with improved safety profiles^12–14. The IStent Inject obtained CE marking in 2010 and subsequently received approval from the U.S. Food and Drug Administration (FDA) in 2012. Thereafter, ongoing regulatory dialogue and stakeholder collaboration underscored the imperative for patient-centered frameworks in the evaluation of novel medical devices^15,16. These developments align with broader trends in healthcare that promote shared decision-making and underscore the importance of incorporating patient-reported outcome measures (PROMs) and patient preference information (PPI) into clinical research and regulatory assessments^17–19.

Health-related quality of life (HRQoL), a central patient-reported outcome, reflects the impact of disease and treatment on patients’ physical, emotional, and social well-being^18,20,21. However, current PROM instruments may lack the sensitivity required to capture the impact of glaucoma, particularly in asymptomatic early stages^21,22. Recent randomized controlled trials have failed to demonstrate clinically meaningful differences in HRQoL using available generic and vision-specific PROM, calling into question their utility as primary endpoints in glaucoma research^23–26.

Emerging evidence suggests that patient preferences vary widely, particularly in weighing treatment benefits against burdens such as medication side effects, procedural risks, and the impact on daily function. Qualitative studies have highlighted patients’ prioritization of outcomes like preserving mobility, maintaining independence, and minimizing treatment burden^27–29. Moreover, treatment burden itself may significantly impair quality of life³⁰. These findings reinforce the need to integrate patient-centered metrics into glaucoma research and practice, especially in light of the growing diversity of therapeutic options.

Given the limitations of current PROM in capturing what truly matters to patients with open-angle glaucoma (OAG)^21–26, there is a growing imperative to develop new glaucoma-specific PROM to better capture disease-specific stressors. To address this gap, we established a collaborative research initiative involving two tertiary-level university hospitals in Spain and the Asociación Glaucoma para Afectados y Familiares (AGAF) [Glaucoma Association for Patients and Families]. This partnership aimed to design a patient-reported outcome instrument specifically for individuals with OAG and cataract who have undergone combined trabecular micro-bypass (TMB) and cataract surgery, utilizing a widely used MIGS procedure.

Methods

Study Design

This study employed a survey-based design targeting members of the AGAF and patients from two tertiary university hospitals who had previously undergone combined TMB (IStent Inject; Glaukos Corporation, Laguna Hills, CA, USA) and phacoemulsification surgery.

The study protocol was reviewed and approved by the Ethics Committee of the San Carlos Clinical Hospital (CEIm Hospital Clínico San Carlos. Sponsor Protocol Code Number: HCSC-IStent Inject W-AGAF; Institutional/Registry Code: 23/505-O_P.) and of the Hospital Universitario Virgen Macarena (CEI 02/2023. Protocol number: SICEIA-2024-000479).

All procedures were conducted in accordance with the principles outlined in the Declaration of Helsinki, the International Council for Harmonization (ICH) Good Clinical Practice (GCP) guidelines, and applicable national regulations, prioritizing whichever standard offered the highest level of participant protection. To protect confidentiality, personal data were de-identified, excluded, or encrypted.

Study participants and inclusion/exclusion criteria

Participants were recruited from the registry of the AGAF. Eligibility criteria included age ≥ 18 years and a confirmed clinical diagnosis of OAG, defined according to the European Glaucoma Society guidelines ¹⁰. Participants were stratified into two subgroups based on treatment status: Subgroup A included patients receiving medical or laser therapy, whereas Subgroup B comprised patients with cataract who had previously undergone combined TMB and cataract surgery IStent Inject device at participating clinical centers.

To capture a broad clinical spectrum of glaucoma management, participants were enrolled from two sources: a patient association (AGAF) and two tertiary hospital surgical departments. Baseline heterogeneity between these groups was anticipated. Notably, the surgical cohort (n = 35) consisted predominantly of patients with mild glaucoma (77.1%), consistent with standard clinical indications for trabecular micro-bypass stent implantation. All statistical analyses were adjusted to account for differences in baseline disease severity.

Patients in the surgical cohort were recruited consecutively during routine postoperative follow-up visits at the participating centers. Only those meeting the inclusion criteria and willing to participate were enrolled. As this was an observational cross-sectional study, no formal record of the total number of eligible patients or recruitment rate was maintained.

Study groups

Participants were categorized into three groups according to glaucoma severity: early, moderate, and advanced stages, according to specific items within the current PROM questionnaire.

PROM development

The questionnaire was developed using a structured, multi-step approach. Initially, a targeted review of existing vision-related and glaucoma-specific PROMs, including the National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) and the Glaucoma Quality of Life-15 (GQL-15), was conducted to identify key domains relevant to visual function and quality of life.

Based on this framework, an initial pool of items was generated de novo to capture additional dimensions not fully addressed by existing instruments, particularly those related to patient expectations, disease perception, and treatment burden in the context of OAG and MIGS.

Item selection and refinement were performed through iterative consensus among glaucoma specialists from the participating centers and representatives of the AGAF, ensuring both clinical relevance and patient-centered content validity.

The final questionnaire was reviewed to eliminate redundancy, optimize clarity, and ensure comprehensive coverage of the domains of interest before being administered to study participants.

Definitions

The questionnaires used for this study are provided in Annexes I and II.

To evaluate the impact of glaucoma on patients’ daily lives and perceived visual quality, a specific Patient-Reported Outcome Measure (PROM) was utilized. This instrument was developed through a multidisciplinary collaboration involving the Association of Glaucoma Patients (Asociación de Glaucoma para Afectados y Familiares, AGAF) and clinical experts from [JMMC] and [MPV].

The PROM consists of 42 items designed to capture a comprehensive profile of visual disability. Completion of the questionnaire requires an average of 10 to 15 min. Regarding the scoring system, 41 items are graded on a 5-point Likert scale ranging from 0 to 4, where higher scores indicate a greater perceived impact or difficulty. One specific item (IV.3.4.), related to IStent Inject W was the first surgery for treating glaucoma, was rated across three categories (0, 1, and 2).

During the study administration, brand-specific terminology was used to maintain consistency with the patients’ clinical documentation; however, the validated domains are designed to be procedure-agnostic.

Glaucoma severity was determined according to participants’ responses to specific items within the PROM questionnaire.

The classification was based on three components: time since diagnosis (Item I.1.5), self-reported visual ability (Item I.1.6), and perceived diagnostic accuracy (Item I.2.1). A weighted mean score was calculated using the following formula:

Weights were assigned to reflect the relative influence of each item, with visual ability (I.1.6) receiving the highest weight (0.6), acknowledging its central role in assessing functional impact.

Based on the resulting value of the weighted average score (), participants were categorized into three glaucoma severity levels: mild ( ≥0 and < 1.5), moderate ( ≥1.5 and < 3.0), and severe ( ≥3.0 ≤ 4.0) (See table S1).

Study outcomes

The primary outcome was to characterize the lived experiences of individuals with OAG, particularly those who have undergone TMB implantation combined with cataract surgery.

The secondary outcomes were to assess the underlying values, needs, preferences, and priorities of individuals diagnosed with glaucoma, with the objective of understanding the subjective impact of the disease and its progressive visual impairment from the patient’s perspective.

Statistical analysis

The current analysis was carried out with MedCalc Statistical Software version 23.3.7 (MedCalc Software Ltd, Ostend, Belgium; https://www.medcalc.org; 2025).

Data was tested for normal distribution using the Shapiro-Wilks test.

As the data did not follow a normal distribution, the Kruskal–Wallis test or the Mann-Whitney test, as appropriate, were used to evaluate differences between the study groups.

The Chi-square test was used to evaluate the differences in qualitative variables between groups.

Because of the large number of tests, simultaneous inference using the Bonferroni correction was used to correct the p-value from individual time points (α/44). Statistical significance was accepted for p < 0.0011.

Results

A total of 240 patients were included in the analysis, with 205 (85.4%) recruited through the AGAF and 35 (14.6%) enrolled via one of the participating clinical centers.

Of the 240 patients included in the analysis, 138 (57.5%) were women and 102 (42.5%) were men.

Regarding the time since glaucoma diagnosis, 11 (4.6%) patients had been diagnosed within the past year (≤ 1 year). A total of 67 (27.9%) patients had received their diagnosis between > 1 and ≤ 5 years prior to study inclusion, while 21 patients (8.8%) had been diagnosed between > 5 and ≤ 10 years earlier. Most participants, 141 (58.8%) patients, had been diagnosed with glaucoma for more than 10 years.

In terms of glaucoma severity, 63 (26.3%) patients were classified as having mild glaucoma, 148 (61.7%) as moderate, and 29 (12.1%) as severe.

Table 1 presents a summary of the key questions and corresponding responses from the PROM questionnaire, analyzed across the total study population, the subgroup of AGAF patients, and individuals treated at participating hospitals.

Table 1.

Overview of the main questions and corresponding responses from the Patient Reported Outcome Measures (PROM) questionnaire in the overall study population, among AGAF patients, and among patients treated at participating hospitals. Percentages are calculated based on the number of responses for each individual item.

Variable	Overall	AGAF	Hospital
Sample, n Patients Eyes	240 240	205 205	35 35
Sex, n (%) Women Men	138 (57.5) 102 (42.5)	126 (61.5) 79 (38.5)	12 (34.3) 23 (65.7)
Glaucoma diagnosis, n (%) ≤ 1 year > 1 to ≤ 5 years > 5 to ≤ 10 years > 10 years	11 (4.6) 67 (27.9) 21 (8.8) 141 (58.8)	7 (3.4) 63 (30.7) 6 (2.9) 129 (62.9)	4 (11.4) 4 (11.4) 15 (42.9) 12 (34.3)
Glaucoma severity, n (%) Mild Moderate Severe	63 (26.3) 148 (61.7) 29 (12.0)	36 (15.6) 140 (68.3) 29 (14.1)	27 (77.1) 8 (28.9) 0 (0.0)
Item I.1.6, n (%) 0 1 2 3 4	0 (0.0) 85 (35.4) 88 (36.7) 10 (4.2) 57 (23.8)	0 (0.0) 85 (41.5) 84 (40.9) 0 (0.0) 36 (17.6)	0 (0.0) 0 (0.0) 4 (11.4) 10 (28.6) 21 (60.0)
Item I.1.7, n (%) 0 1 2 3 4	1 (0.4) 35 (14.6) 83 (34.6) 16 (6.7) 105 (43.8)	0 (0.0) 33 (16.1) 75 (36.6) 1 (0.5) 96 (46.8)	1 (2.9) 2 (5.7) 8 (28.9) 15 (42.9) 9 (25.7)
Item I.2.1, n (%) 0 1 2 3 4	48 (20.0) 28 (11.7) 24 (10.0) 40 (16.7) 100 (41.7)	48 (23.4) 23 (11.2) 20 (9.8) 26 (12.7) 88 (42.9)	0 (0.0) 5 (14.3) 4 (11.4) 14 (40.0) 12 (34.3)
Item I.2.2 0 1 2 3 4	0 (0.0) 1 (0.4) 1 (0.4) 99 (41.4) 138 (57.7)	0 (0.0) 0 (0.0) 0 (0.0) 85 (41.5) 120 (58.5)	0 (0.0) 1 (2.9) 1 (2.9) 14 (40.0) 18 (52.9)
Item I.2.3 0 1 2 3 4	0 (0.0) 63 (26.3) 123 (51.3) 39 (16.3) 15 (6.3)	0 (0.0) 63 (30.7) 122 (59.5) 20 (9.8) 0 (0.0)	0 (0.0) 0 (0.0) 1 (2.9) 19 (54.3) 15 (42.9)
Item I.3.1 0 1 2 3 4	116 (48.3) 53 (22.1) 21 (8.8) 32 (13.3) 18 (7.5)	103 (50.2) 45 (22.0) 12 (5.9) 30 (14.6) 15 (7.3)	13 (37.1) 8 (22.9) 9 (25.7) 2 (5.7) 3 (8.6)
Item I.3.2 0 1 2 3 4	6 (2.5) 50 (20.8) 112 (46.7) 67 (27.9) 5 (2.1)	0 (0.0) 42 (20.5) 103 (50.2) 60 (29.3) 0 (0.0)	6 (17.4) 8 (22.9) 9 (25.7) 7 (20.0) 5 (14.3)
Item I.3.4 0 1 2 3 4	4 (1.7) 23 (9.6) 71 (29.6) 80 (33.3) 62 (25.8)	2 (1.0) 14 (6.8) 60 (29.3) 72 (35.1) 57 (27.8)	2 (5.7) 9 (25.7) 11 (31.4) 8 (22.9) 5 (14.3)
Item I.3.5 0 1 2 3 4	6 (2.5) 64 (26.7) 92 (38.3) 72 (30.0) 6 (2.5)	0 (0.0) 60 (29.3) 82 (40.0) 63 (30.7) 0 (0.0)	6 (17.1) 4 (11.4) 10 (28.6) 9 (25.7) 6 (17.4)
Item I.3.7 0 1 2 3 4	61 (25.4) 44 (18.3) 29 (12.1) 60 (25.0) 46 (19.2)	32 (15.6) 39 (19.0) 29 (14.1) 59 (28.8) 46 (22.4)	29 (82.9) 5 (14.3) 1 (2.9) 0 (0.0) 0 (0.0)
Item I.4.2 0 1 2 3 4	135 (56.3) 42 (17.5) 32 (13.3) 16 (6.7) 15 (6.3)	104 (50.7) 40 (19.5) 30 (14.6) 16 (7.8) 15 (7.3)	31 (88.6) 2 (5.7) 2 (5.7) 0 (0.0) 0 (0.0)
Item I.4.3 0 1 2 3 4	12 (5.0) 67 (27.9) 135 (58.3) 26 (10.8) 0 (0.0)	0 (0.0) 60 (29.3) 125 (61.0) 20 (9.8) 0 (0.0)	12 (34.3) 7 (20.0) 10 (28.6) 6 (17.4) 0 (0.0)
Item II.1.5 0 1 2 3 4	116 (48.3) 57 (23.8) 35 (14.6) 20 (8.3) 12 (5.0)	86 (42.0) 53 (25.9) 34 (16.6) 20 (9.8) 12 (5.9)	30 (85.7) 4 (11.4) 1 (2.9) 0 (0.0) 0 (0.0)
Item II.2.3 0 1 2 3 4	26 (10.9) 35 (14.7) 50 (21.0) 54 (22.7) 73 (30.7)	25 (12.2) 34 (16.6) 44 (21.5) 46 (22.4) 56 (27.3)	1 (2.9) 1 (2.9) 6 (17.4) 8 (24.2) 17 (51.5)
Item II.2.4 0 1 2 3 4	12 (5.1) 43 (18.1) 149 (62.9) 27 (11.4) 6 (2.5)	0 (0.0) 42 (20.5) 143 (69.8) 20 (9.8) 0 (0.0)	12 (37.1) 1 (3.1) 6 (18.8) 7 (21.9) 6 (18.8)
Item II.2.5 0 1 2 3 4	7 (3.0) 83 (35.0) 74 (31.2) 70 (29.5) 3 (1.3)	0 (0.0) 83 (40.5) 62 (30.2) 60 (29.3) 0 (0.0)	7 (21.9) 0 (0.0) 12 (37.5) 10 (31.3) 3 (9.4)
Item II.3.4 0 1 2 3 4	2 (0.9) 41 (17.7) 111 (47.8) 67 (28.9) 11 (4.7)	0 (0.0) 41 (20.0) 104 (50.7) 60 (29.3) 0 (0.0)	2 (7.4) 0 (0.0) 7 (25.9) 7 (25.9) 11 (40.7)
Item II.3.6 0 1 2 3 4	46 (19.2) 72 (30.0) 115 (47.9) 3 (1.3) 4 (1.7)	42 (20.5) 61 (29.8) 102 (49.8) 0 (0.0) 0 (0.0)	4 (11.4) 11 (31.4) 13 (37.1) 3 (8.6) 4 (11.4)
Item III.1.4 0 1 2 3 4	86 (35.8) 31 (12.9) 54 (22.5) 46 (19.6) 22 (9.2)	56 (27.3) 30 (14.6) 51 (24.9) 46 (22.4) 22 (10.7)	30 (85.7) 1 (2.9) 3 (8.6) 1 (2.9) 0 (0.0)
Item III.2.1 0 1 2 3 4	65 (28.0) 18 (7.8) 35 (15.1) 41 (17.7) 73 (31.5)	44 (21.5) 16 (7.8) 32 (15.6) 41 (20.0) 72 (35.1)	21 (77.8) 2 (7.4) 3 (11.1) 0 (0.0) 1 (3.7)
Item IV.2.1 0 1 2 3 4	18 (7.5) 27 (11.3) 69 (28.9) 88 (36.8) 37 (15.5)	18 (8.8) 26 (12.7) 61 (29.8) 70 (34.1) 30 (14.6)	0 (0.0) 1 (2.9) 8 (23.5) 18 (52.9) 7 (20.6)
Item IV.2.2 0 1 2 3 4	NA	NA	21 (63.6) 6 (18.2) 4 (12.1) 1 (3.0) 1 (3.0)
Item IV.2.3 0 1 2 3 4	NA	NA	20 (60.6) 9 (27.3) 3 (9.1) 1 (3.0) 0 (0.0)
Item IV.2.4 0 1 2 3 4	30 (12.6) 38 (16.0) 64 (26.9) 74 (31.1) 32 (13.5)	29 (14.1) 37 (18.0) 57 (27.8) 58 (28.3) 24 (11.7)	1 (3.0) 1 (3.0) 7 (21.2) 16 (48.5) 8 (24.2)
Item IV.2.5 0 1 2 3 4	0 (0.0) 72 (30.3) 93 (39.1) 65 (27.3) 8 (3.4)	0 (0.0) 61 (29.8) 84 (40.9) 60 (29.3) 0 (0.0)	0 (0.0) 11 (33.3) 9 (27.3) 5 (15.2) 8 (24.2)
Item IV.2.6 0 1 2 3 4	18 (7.6) 12 (5.0) 76 (31.9) 107 (45.0) 25 (10.5)	18 (8.8) 12 (5.9) 72 (35.1) 84 (40.9) 19 (9.3)	0 (0.0) 0 (0.0) 4 (12.1) 23 (69.7) 6 (18.2)
Item IV.2.7 0 1 2 3 4	NA	NA	0 (0.0) 0 (0.0) 9 (25.7) 9 (25.7) 17 (48.6)
Item IV.2.8 0 1 2 3 4	NA	NA	34 (97.1) 1 (2.9) 0 (0.0) 0 (0.0) 0 (0.0)
Item IV.2.9 0 1 2 3 4	NA	NA	34 (97.1) 1 (2.9) 0 (0.0) 0 (0.0) 0 (0.0)
Item IV.2.10 0 1 2 3 4	NA	NA	0 (0.0) 0 (0.0) 2 (5.7) 19 (54.3) 14 (40.0)
Item IV.2.11 0 1 2 3 4	NA	NA	6 (17.1) 1 (2.9) 10 (28.6) 9 (25.7) 9 (25.7)
Item IV.2.12 0 1 2 3 4	NA	NA	0 (0.0) 0 (0.0) 1 (2.9) 24 (68.6) 10 (28.6)
Item IV.3.1 0 1 2 3 4	NA	NA	7 (20.0) 10 (28.6) 16 (45.7) 2 (5.7) 0 (0.0)
Item IV.3.2 0 1 2 3 4	NA	NA	0 (0.0) 18 (51.4) 15 (42.9) 2 (5.7) 0 (0.0)
Item IV.3.3 0 1 2 3 4	37 (40.2) 10 (10.9) 23 (25.0) 15 (16.3) 7 (7.6)	17 (29.3) 3 (5.1) 19 (32.8) 13 (22.4) 6 (10.3)	20 (58.8) 7 (20.6) 4 (11.8) 2 (5.9) 1 (2.9)
Item IV.3.4 0 1 2	NA	NA	2 (6.1) 27 (81.8) 4 (12.1)
Item IV.3.5 0 1 2 3 4	NA	NA	13 (56.5) 7 (30.4) 1 (4.4) 0 (0.0) 2 (8.7)
Item IV.3.6 0 1 2 3 4	3 (3.2) 30 (31.9) 25 (26.6) 15 (16.0) 21 (22.3)	3 (5.1) 8 (13.6) 20 (33.9) 15 (25.4) 13 (22.0)	0 (0.0) 22 (62.9) 5 (14.3) 0 (0.0) 8 (22.9)
Item V.1.3.1 0 1 2 3 4	86 (35.8) 30 (12.5) 31 (12.9) 51 (21.3) 42 (17.5)	78 (38.0) 28 (13.7) 26 (12.7) 41 (20.0) 32 (15.6)	8 (22.9) 2 (5.7) 5 (14.3) 10 (28.6) 10 (28.6)
Item V.1.3.2 0 1 2 3 4	105 (44.5) 25 (10.6) 42 (17.8) 34 (14.4) 30 (12.7)	91 (44.4) 23 (11.2) 39 (19.0) 25 (12.2) 27 (13.2)	14 (45.2) 2 (6.5) 3 (9.7) 9 (29.0) 3 (9.7)
Item V.1.3.3 0 1 2 3 4	144 (61.0) 21 (8.9) 38 (16.1) 13 (5.5) 20 (8.5)	126 (61.5) 21 (10.2) 30 (14.6) 9 (4.4) 19 (9.3)	18 (58.1) 0 (0.0) 8 (25.8) 4 (12.9) 1 (3.2)
Item V.1.4 0 1 2 3 4	120 (50.4) 16 (6.7) 35 (14.7) 20 (8.4) 47 (19.8)	109 (53.2) 15 (7.3) 25 (12.2) 17 (8.3) 39 (19.0)	11 (33.3) 1 (3.0) 10 (30.3) 3 (9.1) 8 (24.2)

AGAF: Asociación Glaucoma para Afectados y Familiares (Glaucoma Association for Those Affected and Their Families); NA: Not applicable.

Item I.1.6: Currently, how would you define your visual ability?

0-Blindness.

1-Severely impaired visual capacity.

2-Impaired visual capacity.

3-First symptoms of glaucoma.

4-Full visual capacity.

Item I.1.7: How would you generally rate your quality of life with glaucoma?

0-Very poor, very problematic.

1-Poor, problematic.

2-Moderate, with some problems but satisfactory.

3-Good, generally satisfactory.

4-Very good, very satisfactory.

Item I.2.1: Would you say that your illness was diagnosed in a timely and accurate manner?

0-No, diagnosis was very late and inaccurate.

1-No, diagnosis was late.

2-Intermediate, diagnosis could have been earlier and more precise.

3-Yes, diagnosis was early.

4-Yes, diagnosis was as precise and timely as possible.

Item I.2.2: How does an early and accurate diagnosis really facilitate access to more favorable subsequent treatment for your glaucoma?

0-It is not true at all.

1-It is not very true.

2-It is neither true nor false.

3-It is quite true.

4-It is absolutely true.

Item I.2.3: Do you think the management carried out during your diagnosis has positively influenced the subsequent evolution of your glaucoma?

0-No, it has not had any influence at all.

1-It has not had much influence.

2-It has not had much influence, but it has had some.

3-It has had quite a bit of influence.

4-It has had a lot of influence.

Item I.3.1: Before your diagnosis, did you know what glaucoma was?

0-I had never heard of glaucoma.

1-I had barely heard of glaucoma.

2-I had moderate knowledge of glaucoma.

3-I knew a lot about glaucoma.

4-I had a very broad understanding of the disease.

Item I.3.2: After being diagnosed, assess the level of information available regarding the different treatment options available to you based on your needs.

0-No knowledge.

1-Some knowledge.

2-Moderate knowledge.

3-Extensive knowledge.

4-Very extensive or complete knowledge of the alternatives.

Item I.3.4: To what extent do you consider yourself knowledgeable about glaucoma treatment alternatives today?

0-No knowledge.

1-Some knowledge.

2-Moderate knowledge.

3-Extensive knowledge.

4-Very extensive or complete knowledge of the alternatives.

Item I.3.5: Are you concerned about the severity of your glaucoma?

0-No, not at all.

1-Hardly.

2-Moderately.

3-Quite a bit.

4-Yes, a lot.

Item I.3.7: Have you experienced physical changes due to your glaucoma?

0-No.

1-Yes, but few.

2-Yes, considerably.

3-Yes, quite a few.

4-Yes, many.

Item I.4.2: If you have additional health problems other than glaucoma, would you say they are related to or developed because of glaucoma?

0-They’re not related; I do not have those problems.

1-They’re minimally related.

2-Moderately related.

3-Yes, they are fairly related.

4-Yes, they are completely related.

Item I.4.3: To what extent do these additional health conditions impose a burden on you and those in your immediate social environment in daily life?

0-No, none, or I do not have any such problems.

1-Minimal load.

2-Moderate load.

3-Fairly high load.

4-Very high and serious load.

Item II.1.5: Due to the progression of your glaucoma, how much do you generally rely on someone to help you perform your daily activities?

0-No dependency.

1-Minimal help at specific times.

2-I require some help occasionally.

3-I regularly need help in my daily life.

4-Totally dependent on another person.

Item II.2.3: To what extent have you felt supported in facing these changes?

0-I did not feel supported at all.

1-I felt minimal external support.

2-I felt moderate support.

3-I felt quite supported.

4-I felt completely supported.

Item II.2.4: How many alternatives or facilities have you had to help you normalize your lifestyle with glaucoma?

0-No alternatives.

1-Very few alternatives.

2-I had some alternatives.

3-I had quite a few alternatives.

4-I had many alternatives.

Item II.2.5: How do you evaluate the facilities or alternatives offered to you to normalize your lifestyle with glaucoma?

0-I had no alternatives, or they were no at all useful if I had them.

1-Minimally useful.

2-Moderately useful.

3-Quite useful.

4-Very useful.

Item II.3.4: If you have experienced similar episodes, have you found enough support in your trusted circles to help you overcome them?

0-I did not feel supported at all.

1-I felt minimal external support.

2-I felt moderate support.

3-I felt quite supported.

4-I felt completely supported.

Item II.3.6: To what extent do you feel there is understanding and knowledge at a social level about glaucoma and its physical and psychological consequences?

0-No understanding or knowledge.

1-Minimal understanding or knowledge.

2-Moderate knowledge or understanding.

3-Quite a bit of knowledge or understanding.

4-A lot of or complete knowledge or understanding.

Item III.1.4: Do you regularly encounter barriers to accessing innovative glaucoma treatments?

0-No.

1-Minimal barriers.

2-Moderate barriers.

3-Yes, quite a few barriers.

4-Yes, frequently and significantly so.

Item III.2.1: Do you think that suffering from glaucoma has directly affected your career or job?

0-No.

1-Minimally.

2-Moderately.

3-Quite a bit.

4-Yes, directly.

Item IV.2.1: How would you describe your satisfaction with the drug treatment for your glaucoma?

0-Not at all satisfied.

1-Minimally satisfied.

2-Somewhat satisfied.

3-Quite satisfied.

4-Completely satisfied.

Item IV.2.2: Item IV.2.2: Have you experienced any side effects related to your drug treatment? (prior or without IStent) – Only Hospital.

0-No, none.

1-Minimally.

2-Some.

3-Quite a few.

4-Many, serious.

Item IV.2.3: If you experience such side effects, to what extent do they cause you pain, distress, or discomfort? (prior or without IStent) – Only Hospital.

0-No discomfort, no side effects.

1-Minimal.

2-Some pain.

3-Quite a bit of pain.

4-A lot of pain, severe.

Item IV.2.4: Did you feel confident with the prognosis offered by the drug treatment?

0-No, not at all.

1-Minimally.

2-I feel somewhat safe.

3-I feel quite safe.

4-I feel completely safe.

Item IV.2.5: How much do you understand about your drug treatment?

0-Nothing.

1-The bare minimum.

2-I understand enough.

3-I understand quite a bit.

4-I understand everything or almost everything.

Item IV.2.6: How would you describe your quality of life with drug treatment?

0-Very poor, very problematic.

1-Poor, problematic.

2-Moderate, with some problems, but satisfactory.

3-Good, generally satisfactory.

4-Very good, very satisfactory.

Item IV.2.7: How would you describe your satisfaction with IStent inject^® W surgery for your glaucoma? Only Hospital.

0-Not at all satisfactory.

1-Minimally satisfactory.

2-Somewhat satisfactory.

3-Quite satisfactory.

4-Completely satisfactory.

Item IV.2.8: Have you experienced many side effects related to your surgery? (post-IStent) Only Hospital.

0-No, none.

1-Minimal side effects.

2-Some side effects.

3-Quite a few side effects.

4-Many side effects.

Item IV.2.9: If you experience such side effects, to what extent do they cause you pain, distress, or discomfort? (post-IStent) Only Hospital.

0-No pain, no side effects.

1-Minimal pain or discomfort.

2-Some pain or discomfort.

3-Quite a bit of pain or discomfort.

4-A lot of pain or discomfort.

Item IV.2.10: Do you feel confident about the prognosis offered after surgery with IStent Inject? Only Hospital.

0-No, not at all.

1-Minimally.

2-I feel somewhat safe.

3-I feel quite safe.

4-I feel completely safe.

Item IV.2.11: How much do you understand about the surgery you had and the implanted device (IStent Inject)? Only Hospital.

0-Nothing.

1-The bare minimum.

2-I understand enough.

3-I understand quite a bit.

4-I understand everything or almost everything.

Item IV.2.12: How would you describe your quality of life after surgery with IStent Inject? Only Hospital.

0-Very poor, very problematic.

1-Poor, problematic.

2-Moderate, with some problems, but satisfactory.

3-Good, generally satisfactory.

4-Very good, very satisfactory.

Item IV.3.1: Evaluate how much time you needed to spend on clinical check-ups and general medical care before surgery with IStent Inject. Only Hospital.

0-No time at all.

1-Very little time.

2-Considerable time.

3-Quite a bit of time, more than I consider necessary.

4-Much more time than would be necessary.

Item IV.3.2: Evaluate how much time you need to spend on clinical check-ups and general medical care after surgery with IStent Inject. Only Hospital.

0-No time at all.

1-Very little time.

2-Considerable time.

3-Quite a bit of time, more than I consider necessary.

4-Much more time than would be necessary.

Item IV.3.3: How much of a burden or inconvenience does attending clinical check-ups cause you?

0-Nothing, no burden/inconvenience.

1-It represents a minimal burden/inconvenience.

2-It represents some burden/inconvenience.

3-It represents quite a lot of burden/inconvenience.

4-It represents a very high burden/inconvenience.

Item IV.3.4: Is IStent Inject the first surgery you have received to treat your glaucoma? Only Hospital.

0-I have never had surgery with IStent Inject.

1-Yes, IStent Inject is the first surgery I have received for my glaucoma.

2-No, I have had surgery before and IStent Inject is the second.

Item IV.3.5: If IStent Inject is not your first surgery, how many previous surgeries have you had? Only Hospital.

0-Never had surgery.

1-2 surgeries.

2-3 surgeries.

3-4 surgeries.

4-More than 4 surgeries.

Item IV.3.6: Currently, how stable is your glaucoma prognosis?

0-Very unstable.

1-Quite unstable.

2-Somewhat stable.

3-Quite stable.

4-Completely stable.

Item V.1.3.1: Before your glaucoma diagnosis, how many facilities were offered to you to be able to attend regular eye exams at your medical center?

0-None.

1-Minimal.

2-Some.

3-Quite a few.

4-Many.

Item V.1.3.2: Before your glaucoma diagnosis, how many facilities were offered to you to be able to regularly attend eye exams from your workplace?

0-None.

1-Minimal.

2-Some.

3-Quite a few.

4-Many.

Item V.1.3.3: Before your glaucoma diagnosis, how many opportunities were offered to you to regularly attend ophthalmological check-ups from third-party institutions or associations?

0-None.

1-Minimal.

2-Some.

3-Quite a few.

4-Many.

Item V.1.4: Did these ophthalmological examinations take into account specific glaucoma checks?

0-No, not at all.

1-Minimally, very occasionally.

2-Sometimes.

3-Quite a few times.

4-Always.

Patient Reported Outcome Measures questionnaire according to glaucoma severity

Statistically significant differences were observed across glaucoma severity groups for multiple patient-reported outcome measures. Regarding self-perceived visual ability (Item I.1.6), most patients with mild glaucoma reported full visual capacity (90.5%), whereas all patients with severe glaucoma reported severely impaired vision (p < 0.0001). Similarly, quality of life ratings (Item I.1.7) declined with increasing severity, with 66.7% of mild cases reporting a “very good” quality of life compared to only 20.7% of severe cases (p < 0.0001). Perception of diagnostic timeliness (Item I.2.1) also differed significantly: 79.3% of patients with severe glaucoma believed their diagnosis was “very late and inaccurate,” in contrast to 15.9% in the mild group (p < 0.0001). Moreover, only 20.6% of mild cases felt diagnostic management had a strong positive influence on disease progression (Item I.2.3), compared to none in the severe group (p < 0.0001). Awareness of glaucoma prior to diagnosis (Item I.3.1) was generally low across groups but lowest among severe cases (p = 0.0275), while post-diagnosis knowledge about treatment options (Item I.3.2) was significantly higher in mild cases (p < 0.0001). Concern about disease severity (Item I.3.5) and experience of physical changes (Item I.3.7) both increased with disease progression (p = 0.0250 and p < 0.0001, respectively). The perceived relationship between glaucoma and other health problems (Items I.4.2 and I.4.3) also showed significant associations with disease severity (p < 0.0001 and p = 0.0011, respectively).

Functional dependence (Item II.1.5) increased markedly with severity; 90.5% of mild cases reported no dependency, compared to only 37.9% in the severe group (p < 0.0001). Access to alternatives to normalize life with glaucoma (Item II.2.4) and their perceived usefulness (Item II.2.5) were both significantly lower in the severe group (p < 0.0001 for both). Social support perception (Item II.3.4) also differed, with fewer severe cases reporting strong support (p < 0.0001). Knowledge about glaucoma at the societal level (Item II.3.6) varied significantly by severity, with lower levels perceived among severe cases (p = 0.0009). Barriers to innovative treatment access (Item III.1.4) and the impact of glaucoma on career (Item III.2.1) were reported more frequently by those with more severe disease (p = 0.0002 and p < 0.0001, respectively).

Treatment satisfaction (Item IV.2.1), understanding of treatment (Item IV.2.5), and quality of life under pharmacologic management (Item IV.2.6) also decreased with increasing severity (p = 0.0027, p = 0.0079, and p < 0.0001, respectively). Patients with severe glaucoma reported higher levels of discomfort from treatment side effects (Item IV.2.3; p = 0.0006), and expressed lower confidence in the prognosis offered by their drug regimen (Item IV.2.4; p < 0.0001). Finally, access to regular eye exams through the workplace prior to diagnosis (Item V.1.3.2) showed significant disparities by disease severity, with fewer opportunities reported among severe cases (p = 0.0002).

Table 2 provides a synthesized overview of the principal items and associated PROMs, categorized based on the severity stages of glaucoma.

Table 2.

Overview of the main questions and corresponding responses from the Patient Reported Outcome Measures (PROM) questionnaire according to glaucoma severity. Percentages are calculated based on the number of responses for each individual item. Statistical significance was evaluated using the Chi-squared test.

Variable	Mild1	Moderate2	Severe3	p a
Sample, n Patients Eyes	63 63	148 148	29 29	NA
Glaucoma diagnosis, n (%) ≤ 1 year > 1 to ≤ 5 years > 5 to ≤ 10 years > 10 years	8 (12.7) 23 (36.5) 15 (23.8) 17 (25.0)	3 (2.0) 30 (20.3) 3 (2.0) 112 (75.7)	0 (0.0) 14 (48.3) 3 (10.3) 12 (41.4)	< 0.0001*
Glaucoma severity, n (%) AGAF Hospital	36 (57.1) 27 (42.9)	140 (94.6) 8 (5.4)	29 (100.0) 0 (0.0)	< 0.0001*
Item I.1.6, n (%) 0 1 2 3 4	0 (0.0) 0 (0.0) 0 (0.0) 6 (9.5) 57 (90.5)	0 (0.0) 56 (37.8) 88 (59.5) 4 (2.7) 0 (0.0)	0 (0.0) 29 (100.0) 0 (0.0) 0 (0.0) 0 (0.0)	< 0.0001*
Item I.1.7, n (%) 0 1 2 3 4	0 (0.0) 1 (1.6) 9 (14.3) 11 (17.5) 42 (66.7)	0 (0.0) 23 (15.5) 62 (41.9) 5 (3.4) 58 (39.2)	0 (0.0) 11 (37.9) 12 (41.4) 0 (0.0) 6 (20.7)	< 0.0001*
Item I.2.1, n (%) 0 1 2 3 4	10 (15.9) 14 (22.2) 5 (7.9) 14 (22.2) 20 (31.7)	15 (10.1) 11 (7.4) 16 (10.8) 26 (17.6) 80 (54.1)	23 (79.3) 3 (10.3) 3 (10.3) 0 (0.0) 0 (0.0)	< 0.0001*
Item I.2.2 0 1 2 3 4	0 (0.0) 1 (1.6) 1 (1.6) 17 (27.4) 43 (69.4)	0 (0.0) 0 (0.0) 0 (0.0) 70 (47.3) 78 (52.7)	0 (0.0) 0 (0.0) 0 (0.0) 12 (41.4) 17 (58.6)	0.0624
Item I.2.3 0 1 2 3 4	0 (0.0) 3 (4.8) 28 (44.4) 19 (30.2) 13 (20.6)	0 (0.0) 54 (36.5) 75 (50.7) 17 (11.5) 2 (1.4)	0 (0.0) 6 (20.7) 20 (69.0) 3 (10.3) 0 (0.0)	< 0.0001*
Item I.3.1 0 1 2 3 4	25 (39.7) 19 (30.2) 6 (9.5) 10 (15.9) 3 (4.8)	74 (50.0) 38 (25.7) 9 (6.1) 22 (14.9) 15 (10.1)	17 (58.6) 6 (20.7) 6 (20.7) 0 (0.0) 0 (0.0)	0.0275
Item I.3.2 0 1 2 3 4	5 (7.9) 8 (12.7) 23 (36.5) 22 (34.9) 5 (7.9)	1 (0.7) 36 (24.3) 69 (46.6) 42 (28.4) 0 (0.0)	0 (0.0) 6 (20.7) 20 (69.0) 3 (10.3) 0 (0.0)	< 0.0001*
Item I.3.4 0 1 2 3 4	2 (3.2) 6 (9.5) 19 (30.2) 22 (34.9) 14 (22.2)	2 (1.4) 14 (9.5) 46 (31.1) 49 (33.1) 37 (25.0)	0 (0.0) 3 (10.3) 6 (20.7) 9 (31.0) 11 (37.9)	0.8152
Item I.3.5 0 1 2 3 4	5 (7.9) 18 (28.6) 21 (33.3) 15 (23.8) 4 (6.3)	1 (0.7) 37 (25.0) 60 (40.5) 48 (32.4) 2 (1.4)	0 (0.0) 9 (31.0) 11 (37.9) 9 (31.0) 0 (0.0)	0.0250
Item I.3.7 0 1 2 3 4	36 (57.1) 6 (9.5) 3 (4.8) 15 (23.8) 3 (4.8)	25 (16.9) 35 (23.6) 20 (13.5) 36 (24.3) 32 (21.6)	0 (0.0) 3 (10.3) 6 (20.7) 9 (31.0) 11 (37.9)	< 0.0001*
Item I.4.2 0 1 2 3 4	51 (80.9) 5 (7.9) 2 (3.2) 5 (7.9) 0 (0.0)	69 (46.6) 29 (19.6) 30 (20.3) 8 (5.4) 12 (8.1)	15 (51.7) 8 (27.6) 0 (0.0) 3 (10.3) 3 (10.3)	< 0.0001*
Item I.4.3 0 1 2 3 4	8 (12.7) 25 (39.7) 22 (34.9) 8 (12.7) 0 (0.0)	4 (2.7) 36 (24.3) 93 (62.8) 15 (10.1) 0 (0.0)	0 (0.0) 6 (20.7) 20 (69.0) 3 (10.3) 0 (0.0)	0.0011
Item II.1.5 0 1 2 3 4	57 (90.5) 6 (9.5) 0 (0.0) 0 (0.0) 0 (0.0)	48 (32.4) 42 (28.4) 29 (19.6) 17 (11.5) 12 (8.1)	11 (37.9) 9 (31.0) 6 (20.7) 3 (10.3) 0 (0.0)	< 0.0001*
Item II.2.3 0 1 2 3 4	6 (9.7) 4 (6.5) 14 (22.6) 13 (21.0) 25 (40.3)	15 (10.2) 22 (15.0) 33 (22.4) 35 (23.8) 42 (28.6)	5 (17.2) 9 (31.0) 3 (10.3) 6 (20.7) 6 (20.7)	0.0721
Item II.2.4 0 1 2 3 4	9 (14.8) 8 (13.1) 30 (49.2) 10 (16.4) 4 (6.6)	3 (2.0) 23 (15.6) 107 (72.8) 12 (8.2) 2 (1.4)	0 (0.0) 12 (41.4) 12 (41.4) 5 (17.2) 0 (0.0)	< 0.0001*
Item II.2.5 0 1 2 3 4	5 (8.2) 3 (4.9) 22 (36.1) 29 (47.5) 2 (3.3)	2 (1.4) 68 (46.3) 41 (27.9) 35 (23.8) 1 (0.7)	0 (0.0) 12 (41.4) 11 (37.9) 6 (20.7) 0 (0.0)	< 0.0001*
Item II.3.4 0 1 2 3 4	2 (3.6) 3 (5.4) 24 (42.9) 17 (30.4) 10 (17.9)	0 (0.0) 35 (23.8) 69 (46.9) 42 (28.6) 1 (0.7)	0 (0.0) 3 (10.3) 18 (62.1) 8 (27.6) 0 (0.0)	< 0.0001*
Item II.3.6 0 1 2 3 4	4 (6.3) 14 (22.2) 39 (61.9) 3 (4.8) 3 (4.8)	33 (22.3) 55 (37.2) 59 (39.9) 0 (0.0) 1 (0.7)	9 (31.0) 3 (10.3) 17 (58.6) 0 (0.0) 0 (0.0)	0.0009*
Item III.1.4 0 1 2 3 4	34 (54.0) 10 (15.9) 9 (14.3) 4 (6.3) 6 (9.5)	46 (31.1) 21 (14.2) 33 (22.3) 37 (25.0) 11 (7.4)	6 (20.7) 0 (0.0) 12 (41.4) 6 (20.7) 5 (17.2)	0.0002*
Item III.2.1 0 1 2 3 4	29 (50.9) 5 (8.9) 16 (28.6) 3 (5.4) 4 (7.1)	36 (24.6) 13 (8.9) 19 (13.0) 26 (17.8) 52 (35.6)	0 (0.0) 0 (0.0) 0 (0.0) 12 (41.4) 17 (58.6)	< 0.0001*
Item IV.2.1 0 1 2 3 4	0 (0.0) 6 (9.7) 16 (25.8) 27 (43.5) 13 (21.0)	12 (8.1) 15 (10.1) 42 (28.4) 55 (37.2) 24 (16.2)	6 (20.7) 6 (20.7) 11 (37.9) 6 (20.7) 0 (0.0)	0.0027
Item IV.2.2 0 1 2 3 4	16 (64.0) 4 (16.0) 4 (16.0) 0 (0.0) 1 (4.0)	5 (62.5) 2 (25.0) 0 (0.0) 1 (12.5) 0 (0.0)	NA	0.2876
Item IV.2.3 0 1 2 3 4	25 (41.0) 16 (26.2) 11 (18.0) 9 (14.8) 0 (0.0)	32 (21.6) 18 (12.2) 32 (21.6) 46 (31.1) 20 (13.5)	6 (20.7) 3 (10.3) 5 (17.2) 12 (41.4) 3 (10.3)	0.0006*
Item IV.2.4 0 1 2 3 4	8 (13.1) 3 (4.9) 17 (27.9) 26 (42.6) 7 (11.5)	11 (7.4) 29 (19.6) 38 (25.7) 45 (30.4) 25 (16.9)	11 (37.9) 6 (20.7) 9 (31.0) 3 (10.3) 0 (0.0)	< 0.0001*
Item IV.2.5 0 1 2 3 4	0 (0.0) 16 (26.2) 24 (39.3) 14 (22.9) 7 (11.5)	0 (0.0) 48 (32.4) 57 (38.5) 42 (28.4) 1 (0.7)	0 (0.0) 8 (27.6) 12 (41.4) 9 (31.0) 0 (0.0)	0.0079
Item IV.2.6 0 1 2 3 4	0 (0.0) 0 (0.0) 14 (22.9) 36 (59.0) 11 (18.0)	15 (10.1) 12 (8.1) 42 (28.4) 65 (43.9) 14 (9.5)	3 (10.3) 0 (0.0) 20 (69.0) 6 (20.7) 0 (0.0)	< 0.0001*
Item IV.2.7 0 1 2 3 4	0 (0.0) 0 (0.0) 7 (25.9) 8 (29.6) 12 (44.4)	0 (0.0) 0 (0.0) 2 (25.0) 1 (12.5) 5 (62.5)	NA	0.5711
Item IV.2.8 0 1 2 3 4	26 (96.3) 1 (3.7) 0 (0.0) 0 (0.0) 0 (0.0)	8 (100.0) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0)	NA	0.5862
Item IV.2.9 0 1 2 3 4	26 (96.3) 1 (3.7) 0 (0.0) 0 (0.0) 0 (0.0)	8 (100.0) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0)	NA	0.5862
Item IV.2.10 0 1 2 3 4	0 (0.0) 0 (0.0) 1 (3.7) 15 (55.6) 11 (40.7)	0 (0.0) 0 (0.0) 1 (12.5) 4 (50.0) 3 (37.5)	NA	0.6418
Item IV.2.11 0 1 2 3 4	4 (14.8) 0 (0.0) 9 (33.3) 6 (22.2) 8 (29.6)	2 (25.0) 1 (12.5) 1 (12.5) 3 (37.5) 1 (12.59	NA	0.2029
Item IV.2.12 0 1 2 3 4	0 (0.0) 0 (0.0) 1 (3.7) 18 (66.7) 8 (29.6)	0 (0.0) 0 (0.0) 0 (0.0) 6 (75.0) 2 (25.0)	NA	0.8166
Item IV.3.1 0 1 2 3 4	7 (22.6) 6 (19.4) 13 (41.9) 5 (16.1) 0 (0.0)	6 (12.5) 13 (27.1) 20 (41.7) 9 (18.8) 0 (0.0)	0 (0.0) 0 (0.0) 2 (100.0) 0 (0.0) 0 (0.0)	0.6170
Item IV.3.2 0 1 2 3 4	12 (44.4) 13 (41.9) 2 (7.4) 0 (0.0) 0 (0.0)	6 (75.0) 2 (25.0) 0 (0.0) 0 (0.0) 0 (0.0)	NA	0.2887
Item IV.3.3 0 1 2 3 4	21 (58.3) 4 (11.1) 6 (16.7) 4 (11.1) 1 (2.8)	14 (25.9) 6 (11.1) 17 (31.5) 11 (20.4) 6 (11.1)	2 (100.0) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0)	0.1874
Item IV.3.4 0 1 2	1 (3.9) 23 (88.5) 2 (7.7)	1 (14.3) 4 (57.1) 2 (28.6)	NA	0.1623
Item IV.3.5 0 1 2 3 4	9 (52.9) 5 (29.4) 1 (5.9) 0 (0.0) 2 (11.8)	4 (66.7) 2 (33.3) 0 (0.0) 0 (0.0) 0 (0.0)	NA	0.7460
Item IV.3.6 0 1 2 3 4	0 (0.0) 16 (43.2) 7 (18.9) 3 (8.1) 11 (29.7)	3 (5.5) 14 (25.5) 16 (29.1) 12 (21.8) 10 (18.2)	0 (0.0) 0 (0.0) 2 (100.0) 0 (0.0) 0 (0.0)	0.0656
Item V.1.3.1 0 1 2 3 4	19 (30.2) 8 (12.7) 3 (4.8) 22 (34.9) 11 (17.5)	57 (38.5) 18 (12.2) 25 (16.9) 24 (16.2) 24 (16.2)	10 (34.5) 4 (13.8) 3 (10.3) 6 (20.7) 6 (20.7)	0.0935
Item V.1.3.2 0 1 2 3 4	20 (32.8) 8 (13.1) 12 (19.7) 15 (24.6) 6 (9.8)	69 (47.3) 8 (5.5) 27 (18.5) 18 (12.3) 24 (16.4)	17 (58.6) 9 (31.0) 3 (10.3) 0 (0.0) 0 (0.0)	0.0002*
Item V.1.3.3 0 1 2 3 4	32 (51.6) 10 (16.1) 12 (19.4) 2 (3.2) 6 (9.7)	91 (62.8) 9 (6.2) 26 (17.9) 8 (5.5) 11 (7.6)	20 (69.0) 3 (10.3) 0 (0.0) 3 (10.3) 3 (10.3)	0.0972
Item V.1.4 0 1 2 3 4	27 (43.5) 8 (12.9) 8 (12.9) 6 (9.7) 13 (21.0)	75 (51.0) 6 (4.1) 21 (14.3) 11 (7.5) 34 (23.1)	19 (65.5) 1 (3.4) 6 (20.7) 3 (10.3) 0 (0.0)	0.0489

¹Weigthed mean ≥ 0 and < 1.5. ²Weigthed mean ≥ 1.5 and < 3.0. ³Weigthed mean ≥ 3.0 ≤ 4.0. *Significant results are indicated by an asterisk (*), based on a Bonferroni-corrected alpha level of p < 0.0011. AGAF: Asociación Glaucoma para Afectados y Familiares (Glaucoma Association for Those Affected and Their Families); NA: Not applicable.

Item I.1.6: Currently, how would you define your visual ability?

0-Blindness.

1-Severely impaired visual capacity.

2-Impaired visual capacity.

3-First symptoms of glaucoma.

4-Full visual capacity.

Item I.1.7: How would you generally rate your quality of life with glaucoma?

0-Very poor, very problematic.

1-Poor, problematic.

2-Moderate, with some problems but satisfactory.

3-Good, generally satisfactory.

4-Very good, very satisfactory.

Item I.2.1: Would you say that your illness was diagnosed in a timely and accurate manner?

0-No, diagnosis was very late and inaccurate.

1-No, diagnosis was late.

2-Intermediate, diagnosis could have been earlier and more precise.

3-Yes, diagnosis was early.

4-Yes, diagnosis was as precise and timely as possible.

Item I.2.2: How does an early and accurate diagnosis really facilitate access to more favorable subsequent treatment for your glaucoma?

0-It is not true at all.

1-It is not very true.

2-It is neither true nor false.

3-It is quite true.

4-It is absolutely true.

Item I.2.3: Do you think the management carried out during your diagnosis has positively influenced the subsequent evolution of your glaucoma?

0-No, it has not had any influence at all.

1-It has not had much influence.

2-It has not had much influence, but it has had some.

3-It has had quite a bit of influence.

4-It has had a lot of influence.

Item I.3.1: Before your diagnosis, did you know what glaucoma was?

0-I had never heard of glaucoma.

1-I had barely heard of glaucoma.

2-I had moderate knowledge of glaucoma.

3-I knew a lot about glaucoma.

4-I had a very broad understanding of the disease.

Item I.3.2: After being diagnosed, assess the level of information available regarding the different treatment options available to you based on your needs.

0-No knowledge.

1-Some knowledge.

2-Moderate knowledge.

3-Extensive knowledge.

4-Very extensive or complete knowledge of the alternatives.

Item I.3.4: To what extent do you consider yourself knowledgeable about glaucoma treatment alternatives today?

0-No knowledge.

1-Some knowledge.

2-Moderate knowledge.

3-Extensive knowledge.

4-Very extensive or complete knowledge of the alternatives.

Item I.3.5: Are you concerned about the severity of your glaucoma?

0-No, not at all.

1-Hardly.

2-Moderately.

3-Quite a bit.

4-Yes, a lot.

Item I.3.7: Have you experienced physical changes due to your glaucoma?

0-No.

1-Yes, but few.

2-Yes, considerably.

3-Yes, quite a few.

4-Yes, many.

Item I.4.2: If you have additional health problems other than glaucoma, would you say they are related to or developed because of glaucoma?

0-They’re not related; I do not have those problems.

1-They’re minimally related.

2-Moderately related.

3-Yes, they are fairly related.

4-Yes, they are completely related.

Item I.4.3: To what extent do these additional health conditions impose a burden on you and those in your immediate social environment in daily life?

0-No, none, or I do not have any such problems.

1-Minimal load.

2-Moderate load.

3-Fairly high load.

4-Very high and serious load.

Item II.1.5: Due to the progression of your glaucoma, how much do you generally rely on someone to help you perform your daily activities?

0-No dependency.

1-Minimal help at specific times.

2-I require some help occasionally.

3-I regularly need help in my daily life.

4-Totally dependent on another person.

Item II.2.3: To what extent have you felt supported in facing these changes?

0-I did not feel supported at all.

1-I felt minimal external support.

2-I felt moderate support.

3-I felt quite supported.

4-I felt completely supported.

Item II.2.4: How many alternatives or facilities have you had to help you normalize your lifestyle with glaucoma?

0-No alternatives.

1-Very few alternatives.

2-I had some alternatives.

3-I had quite a few alternatives.

4-I had many alternatives.

Item II.2.5: How do you evaluate the facilities or alternatives offered to you to normalize your lifestyle with glaucoma?

0-I had no alternatives, or they were no at all useful if I had them.

1-Minimally useful.

2-Moderately useful.

3-Quite useful.

4-Very useful.

Item II.3.4: If you have experienced similar episodes, have you found enough support in your trusted circles to help you overcome them?

0-I did not feel supported at all.

1-I felt minimal external support.

2-I felt moderate support.

3-I felt quite supported.

4-I felt completely supported.

Item II.3.6: To what extent do you feel there is understanding and knowledge at a social level about glaucoma and its physical and psychological consequences?

0-No understanding or knowledge.

1-Minimal understanding or knowledge.

2-Moderate knowledge or understanding.

3-Quite a bit of knowledge or understanding.

4-A lot of or complete knowledge or understanding.

Item III.1.4: Do you regularly encounter barriers to accessing innovative glaucoma treatments?

0-No.

1-Minimal barriers.

2-Moderate barriers.

3-Yes, quite a few barriers.

4-Yes, frequently and significantly so.

Item III.2.1: Do you think that suffering from glaucoma has directly affected your career or job?

0-No.

1-Minimally.

2-Moderately.

3-Quite a bit.

4-Yes, directly.

Item IV.2.1: How would you describe your satisfaction with the drug treatment for your glaucoma?

0-Not at all satisfied.

1-Minimally satisfied.

2-Somewhat satisfied.

3-Quite satisfied.

4-Completely satisfied.

Item IV.2.2: Item IV.2.2: Have you experienced any side effects related to your drug treatment? (prior or without IStent) – Only Hospital.

0-No, none.

1-Minimally.

2-Some.

3-Quite a few.

4-Many, serious.

Item IV.2.3: If you experience such side effects, to what extent do they cause you pain, distress, or discomfort? (prior or without IStent) – Only Hospital.

0-No discomfort, no side effects.

1-Minimal.

2-Some pain.

3-Quite a bit of pain.

4-A lot of pain, severe.

Item IV.2.4: Did you feel confident with the prognosis offered by the drug treatment?

0-No, not at all.

1-Minimally.

2-I feel somewhat safe.

3-I feel quite safe.

4-I feel completely safe.

Item IV.2.5: How much do you understand about your drug treatment?

0-Nothing.

1-The bare minimum.

2-I understand enough.

3-I understand quite a bit.

4-I understand everything or almost everything.

Item IV.2.6: How would you describe your quality of life with drug treatment?

0-Very poor, very problematic.

1-Poor, problematic.

2-Moderate, with some problems, but satisfactory.

3-Good, generally satisfactory.

4-Very good, very satisfactory.

Item IV.2.7: How would you describe your satisfaction with IStent Inject W surgery for your glaucoma? Only Hospital.

0-Not at all satisfactory.

1-Minimally satisfactory.

2-Somewhat satisfactory.

3-Quite satisfactory.

4-Completely satisfactory.

Item IV.2.8: Have you experienced many side effects related to your surgery? (post-IStent) Only Hospital.

0-No, none.

1-Minimal side effects.

2-Some side effects.

3-Quite a few side effects.

4-Many side effects.

Item IV.2.9: If you experience such side effects, to what extent do they cause you pain, distress, or discomfort? (post-IStent) Only Hospital.

0-No pain, no side effects.

1-Minimal pain or discomfort.

2-Some pain or discomfort.

3-Quite a bit of pain or discomfort.

4-A lot of pain or discomfort.

Item IV.2.10: Do you feel confident about the prognosis offered after surgery with IStent Inject? Only Hospital.

0-No, not at all.

1-Minimally.

2-I feel somewhat safe.

3-I feel quite safe.

4-I feel completely safe.

Item IV.2.11: How much do you understand about the surgery you had and the implanted device (IStent Inject)? Only Hospital.

0-Nothing.

1-The bare minimum.

2-I understand enough.

3-I understand quite a bit.

4-I understand everything or almost everything.

Item IV.2.12: How would you describe your quality of life after surgery with IStent Inject? Only Hospital.

0-Very poor, very problematic.

1-Poor, problematic.

2-Moderate, with some problems, but satisfactory.

3-Good, generally satisfactory.

4-Very good, very satisfactory.

Item IV.3.1: Evaluate how much time you needed to spend on clinical check-ups and general medical care before surgery with IStent Inject. Only Hospital.

0-No time at all.

1-Very little time.

2-Considerable time.

3-Quite a bit of time, more than I consider necessary.

4-Much more time than would be necessary.

Item IV.3.2: Evaluate how much time you need to spend on clinical check-ups and general medical care after surgery with IStent Inject. Only Hospital.

0-No time at all.

1-Very little time.

2-Considerable time.

3-Quite a bit of time, more than I consider necessary.

4-Much more time than would be necessary.

Item IV.3.3: How much of a burden or inconvenience does attending clinical check-ups cause you?

0-Nothing, no burden/inconvenience.

1-It represents a minimal burden/inconvenience.

2-It represents some burden/inconvenience.

3-It represents quite a lot of burden/inconvenience.

4-It represents a very high burden/inconvenience.

Item IV.3.4: Is iStent inject the first surgery you have received to treat your glaucoma? Only Hospital.

0-I have never had surgery with IStent Inject.

1-Yes, IStent Inject is the first surgery I have received for my glaucoma.

2-No, I have had surgery before and IStent Inject is the second.

Item IV.3.5: If IStent Inject is not your first surgery, how many previous surgeries have you had? Only Hospital.

0-Never had surgery.

1-2 surgeries.

2-3 surgeries.

3-4 surgeries.

4-More than 4 surgeries.

Item IV.3.6: Currently, how stable is your glaucoma prognosis?

0-Very unstable.

1-Quite unstable.

2-Somewhat stable.

3-Quite stable.

4-Completely stable.

Item V.1.3.1: Before your glaucoma diagnosis, how many facilities were offered to you to be able to attend regular eye exams at your medical center?

0-None.

1-Minimal.

2-Some.

3-Quite a few.

4-Many.

Item V.1.3.2: Before your glaucoma diagnosis, how many facilities were offered to you to be able to regularly attend eye exams from your workplace?

0-None.

1-Minimal.

2-Some.

3-Quite a few.

4-Many.

Item V.1.3.3: Before your glaucoma diagnosis, how many opportunities were offered to you to regularly attend ophthalmological check-ups from third-party institutions or associations?

0-None.

1-Minimal.

2-Some.

3-Quite a few.

4-Many.

Item V.1.3.4: Did these ophthalmological examinations take into account specific glaucoma checks?

0-No, not at all.

1-Minimally, very occasionally.

2-Sometimes.

3-Quite a few times.

4-Always.

Aspects related to istent inject surgery and glaucoma management

Among patients treated with the IStent Inject device combined with cataract surgery, 26 out of 35 (74.3%) reported being either “quite satisfied” or “very satisfied” with the surgical outcome (Fig. 1). No statistically significant differences in satisfaction levels were observed between patients with mild and moderate glaucoma (χ² test, p = 0.5711).

Fig. 1.

Distribution of satisfaction levels among the 35 patients who underwent combined IStent implant and cataract surgery.

The incidence and impact of treatment-related adverse events (AEs) were minimal across the study population, with 97% of patients reported no AEs, and only 3% experienced minimal AEs. Similarly, the perceived impact of AEs, specifically in terms of pain or discomfort, was negligible, with 97% of patients reporting no such symptoms and 3% reporting only minimal discomfort.

With respect to patients’ confidence in the postoperative prognosis following the IStent Inject surgery, 33 patients (94.3%) reported being either “totally confident” or “quite confident” in the prognosis provided. No statistically significant difference was observed between patients with mild and moderate glaucoma ((χ² test, p = 0.7400).

Similarly, 34 patients (97%) rated their quality of life as “very good” or “good” following combined IStent Inject surgery, with no statistically significant differences observed across different levels of glaucoma severity (χ² test, p = 0.9230).

Discussion

The primary aim of this investigation was to assess the treatment outcome preferences and therapeutic expectations of individuals diagnosed with OAG undergoing minimally invasive TMB and cataract surgery, encompassing a heterogeneous cohort with varying stages of disease progression and prior treatment histories. A comprehensive understanding of patient-centered outcomes necessitates systematic and methodologically robust qualitative inquiry directly involving patient input. To this end, participants were engaged in identifying and ranking the outcomes they deemed most salient in relation to their surgical experience and subsequent postoperative quality of life.

The analysis of 240 participants revealed that the majority had been living with glaucoma for over a decade and presented with moderate disease severity. Significant associations were observed between glaucoma severity and a wide range of patient-reported outcomes. Individuals with more advanced disease consistently reported poorer self-perceived visual function, diminished quality of life, delayed and inaccurate diagnosis, and reduced awareness of glaucoma and its treatments. Functional dependence, physical changes, and psychosocial burdens, including limited social support and career impact, were more pronounced in severe cases. Additionally, patients with advanced glaucoma expressed lower treatment satisfaction, reduced confidence in medical management, and greater concerns about side effects. Access to workplace-based screening and awareness of societal knowledge about glaucoma were also notably lower among those with severe disease.

Among patients undergoing treatment with the IStent Inject device during their cataract surgery, the majority (74.3%) reported high levels of satisfaction with surgical outcomes, with no statistically significant differences observed between mild and moderate glaucoma subgroups. Adverse events were rare and had minimal impact; 97% of participants reported no complications, and only a small proportion experienced minor discomfort. Confidence in the postoperative prognosis was notably high, with 94.3% of patients expressing either full or substantial confidence, regardless of disease severity. Furthermore, 97% rated their postoperative quality of life as good or very good, with no significant variation across glaucoma severity levels.

While the initial validation of this PROM was conducted in patients receiving the IStent Inject device, the items were designed to capture stressors common to most MIGS. By using broader terminology such as ‘glaucoma implant’ or ‘procedural outcome’ in the final version of the instrument, we have ensured that the tool can be utilized by the wider glaucoma community to evaluate various surgical interventions.

Glaucoma clinical trials have traditionally prioritized surrogate endpoints such as IOP, which, while methodologically convenient, may not align with patients lived experiences or treatment priorities. Overreliance on IOP reduction can obscure outcomes that matter more to patients, such as functional vision and quality of life, particularly in early disease stages^18,31. This has prompted calls to incorporate PROM into study designs to better capture meaningful therapeutic benefits.

PROM are essential tools for evaluating patients’ perceived health status and HRQoL. Despite their relevance, the selection of appropriate PROM remains challenging due to the wide variability and inconsistent quality among available instruments. A review by Vandenbroeck et al. identified 27 PROMs, 18 of which were glaucoma-specific, but noted significant limitations, including the absence of conceptual frameworks and insufficient patient input during development³². Che Hamzah et al. identified 33 PROMs and highlighted the NEI-VFQ-25, IVI, and TSS-IOP for their strong content validity³³. Khadka et al. recommended the GAL-9/10 for assessing activity limitation and subsequently developed a glaucoma-specific item bank of 342 items across ten HRQoL domains, largely derived from patient focus groups^34,35.

To improve the consistency and quality of PROM data, guidelines such as SPIRIT-PRO and CONSORT-PRO have been established for protocol and reporting standards in clinical trials³⁶. Additionally, other models for standardized analysis of PROM in other medical fields may be adapted for glaucoma research³⁷.

While there has been progress in PROM development and application, further work is necessary to understand and quantify the impact of PROM measurement in both ophthalmic research and clinical care. A systematic review has highlighted the existence of various methodological models to assess the broader healthcare implications of research³⁸. Looking ahead, it will be essential not only to refine PROM tools for greater accuracy and relevance, but also to explore how their integration into glaucoma care influences clinical outcomes, decision-making, and ultimately, patient well-being.

The survey indicated that delayed glaucoma diagnosis correlated with poorer visual outcomes, reduced quality of life, and lower confidence in diagnostic accuracy, particularly among patients with severe disease.

Some of the main aspects to be assessed would be those related to the treatment of glaucoma. Regarding pharmacological management, although patients generally feel well-informed, those in the severe stage express lower satisfaction, greater discomfort from side effects, and less confidence in treatment outcomes, alongside a significantly lower perceived quality of life.

Over the past two decades, the evolution of MIGS techniques for IOP reduction has significantly transformed the therapeutic landscape of glaucoma management. These surgical interventions are now increasingly recognized as viable and effective options, even in earlier stages of the disease, contributing to a paradigm shift in clinical practice. These advancements have supported the consideration of surgical interventions earlier in the disease course, particularly in cases of mild to moderate glaucoma¹³. This evolving treatment paradigm has been further bolstered by evidence demonstrating that the combination of cataract extraction with MIGS can achieve clinically meaningful IOP reduction and decrease the need for postoperative pharmacologic therapy³⁹ as was the case in our study. With the continued innovation and increasing adoption of MIGS procedures, there is a pressing need for robust assessment tools to ensure these novel interventions align with patient-centered care objectives.

A wide array of microincisional techniques and devices have been developed to enhance aqueous humor outflow and achieve effective IOP control. Despite the growing number of interventions, only a limited subset has been subjected to rigorously controlled, prospective, multicenter randomized clinical trials. Among these, certain implantable MIGS devices have demonstrated a favorable safety and efficacy profile, receiving regulatory approval from the U.S. Food and Drug Administration (FDA)⁴⁰. Nevertheless, the pace of technological advancement in glaucoma surgery underscores the importance of aligning clinical outcomes with endpoints that are meaningful to patients.

According to the results of the current survey, the implantation of the IStent Inject device in combination with cataract surgery demonstrated favorable outcomes as reported by the PROM. Patients generally reported adequate understanding of the procedure and the implant. Postoperative satisfaction was high, with over 97% experiencing no adverse effects, discomfort, or pain, and approximately 95% expressing moderate to full confidence in the surgical prognosis. Moreover, quality of life was perceived as higher among surgical patients, with more than 97% rating it as satisfactory or very satisfactory.

This study has several limitations that should be acknowledged. First, the sample was drawn from a heterogeneous population, including patients from two tertiary referral centers and members of a glaucoma patient association. As a result, selection bias may be present, and caution is warranted when attempting to generalize these findings to the broader glaucoma population. Second, the PROM used in this study had not been previously validated in other glaucoma populations or clinical settings. Although the questionnaire yielded consistent findings regarding the functional impact of glaucoma across visual domains, its psychometric properties, including reliability, validity, and sensitivity to change, remain to be formally established. Additionally, the cross-sectional nature of the survey limits the ability to draw causal inferences or assess changes over time. An additional limitation is the potential selection bias due to the unequal distribution of glaucoma severity between groups. The combined IStent and cataract cohort was predominantly composed of mild cases (77.1%), whereas the AGAF group showed a broader severity distribution (15% mild, 68% moderate, 14.1% severe), reflecting routine clinical practice in which minimally invasive glaucoma surgery is typically indicated for early-stage disease. This imbalance restricts direct comparisons of PROM scores across severity strata; however, it also reflects real-world differences between contemporary surgical pathways and long-term medical management. Furthermore, a limitation of this study is that validation was conducted exclusively in a Spanish-speaking cohort. While an English translation is provided (see Appendix Y) to facilitate international peer review and future research, we emphasize that formal cross-cultural adaptation and linguistic validation are required before the instrument can be implemented in English-speaking clinical settings. The cross-sectional design of PROM administration introduces potential bias related to disease duration. Patients with long-standing glaucoma (> 10 years) may develop adaptive coping strategies and altered perceptions of visual function compared with recently diagnosed individuals. As this temporal adaptation was not controlled for, quality-of-life scores may be influenced by differences in disease chronicity. Accordingly, the findings should be interpreted as a cross-sectional snapshot of a heterogeneous population at varying stages of follow-up. A potential bias was identified regarding the high level of disease awareness among AGAF members. Their increased health literacy likely influenced their responses to the PROM, potentially limiting the generalizability of the results to the broader, less-informed glaucoma population. Furthermore, the specialized care provided at tertiary hospitals, including frequent check-ups and access to innovative treatments, likely influenced the clinical outcomes and perceptions of the surgical cohort. We acknowledged that this high level of clinical support may limit the generalizability of the findings to patients managed in primary or secondary care settings. The questionnaire was completed independently by patients, which might be a limitation due to potential variability in item interpretation without clinical supervision. However, this approach was intentionally chosen to minimize observer-induced bias and better reflect patients’ self-perceived visual quality in a natural, unsupervised setting. Another limitation of this study is that the PROM did not explicitly account for disease bilaterality. Given that binocular visual function and the involvement of both eyes are important determinants of quality of life in glaucoma, the absence of specific items addressing unilateral versus bilateral disease may have influenced the interpretation of patient-reported outcomes. Future refinements of the instrument will aim to incorporate measures of laterality and binocular visual function to improve its clinical sensitivity.

The reliance on self-reported data may also introduce recall bias or subjective interpretation of items, particularly in questions related to prognosis or treatment outcomes. Finally, a primary limitation of this study is the inability to distinguish the individual contributions of phacoemulsification and iStent implantation to the observed improvements in quality of life; consequently, the results should be interpreted as the collective outcome of the combined surgical intervention. It would be interesting to perform the same questionnaire on patients having the Istent Inject as a standalone procedure, both in phakic and pseudophakic eyes. Despite these limitations, the PROM instrument provided valuable multidimensional insights, spanning physical, psychological, social, and economic domains, that are critical for understanding the patient experience and guiding the future development of patient-centered outcome measures.

Conclusions

This study highlighted the impact of delayed glaucoma diagnosis and disease severity on patients’ perceived visual function, quality of life, and treatment experience. More advanced stages were associated with increased physical, psychological, social, and economic burdens, along with lower treatment satisfaction. These findings underscore the importance of early detection, patient education, and accessible screening initiatives. Patients treated with the IStent Inject combined with cataract surgery reported high satisfaction and minimal postoperative discomfort, although these results should be interpreted within the broader framework of comprehensive glaucoma management. Early-stage disease control remained essential for preserving quality of life and reducing long-term burden.

Future clinical trials should incorporate outcomes that reflect patient-reported functioning, well-being, treatment burden, and visual experience. Integrating the patient perspective into disease evaluation and management may support therapeutic innovation, improve shared decision-making, and enhance treatment relevance. Future research will focus on the continued psychometric refinement of this instrument. Specifically, a head-to-head comparison against established glaucoma-specific PROMs, such as the GQL-15 or the NEI-VFQ-25, is planned to evaluate concurrent validity.

Statements

Compliance with ethics guidelines

The studies were conducted in accordance with the local legislation and institutional requirements. The study protocol was reviewed and approved by the Ethics Committee of the San Carlos Clinical Hospital (CEIm Hospital Clínico San Carlos. Sponsor Protocol Code Number: HCSC-iStent inject^® W-AGAF; Institutional/Registry Code: 23/505-O_P.) and of the Hospital Universitario Virgen Macarena (CEI 02/2023. Protocol number: SICEIA-2024-000479).

Supplementary Information

Below is the link to the electronic supplementary material.

Author contributions

Conceptualization: JMMC, MPV, TJ, JMCB; Methodology: JMMC, MPV, VRG; Formal analysis: LRA, VRG; Investigation: JMMC, MPV, LRA, VRG, TJ, JMCB; Supervision: JMMC, TJ, JMCB. All authors met the ICMJE authorship criteria. All authors made substantial contributions to conception, design, analysis, and interpretation of data, contributed to writing the article, provided critical revision of the manuscript, and approved the final version.

Funding

Medical writing and editorial assistant were funded by Glaukos Medical Spain S.L. Glaukos Medical Spain S.L. was not involved in the preparation of the recommendations nor did the company influence in any way the scientific consensus reached.

Data availability

The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding authors.

Declarations

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Competing interests

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.JMC: Grants: Santen, Ivantis, Abbvie, Viatris, Glaukos, Thea, Omikron, Nova Eye Medical, Vialase. Consultant: Abbvie, Santen, Alcon, Viatris, Novartis, Thea, B&L, Glaukos, AJL, Visufarma, Angelini. Speaker: Abbvie, Santen, Alcon, Viatris, Novartis, Thea, B&L, Glaukos, iCare, Angelini, Nova Eye Medical.The rest of the authors do not have any conflict to declare.

Informed Consent

The participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.