Air/gas migration after descemet membrane endothelial keratoplasty (DMEK): the impact of scleral-fixated versus posterior chamber intraocular lenses

Abstract

Background

To evaluate factors associated with posterior migration of intracameral air/gas into the vitreous cavity following Descemet membrane endothelial keratoplasty (DMEK).

Methods

This retrospective case series included 30 eyes of patients with posterior chamber intraocular lenses (PCIOLs) and 11 eyes of patients with scleral-fixated intraocular lenses (SFIOLs) who underwent DMEK surgery. Preoperative variables potentially associated with posterior air/gas migration were recorded, including the type of intraocular lens, anterior chamber depth (ACD), pupil diameter, intraocular pressure (IOP), history of pars plana vitrectomy (PPV), and presence of iris defects. Preoperative and postoperative corrected and uncorrected visual acuity levels were assessed for all patients. Graft detachment and subsequent rebubbling were documented.

Results

Age, ACD, IOP, and preoperative and postoperative best-corrected visual acuity (BCVA) were similar between the groups (p > 0.05). The mean pupil diameter was significantly larger in the SFIOL group than in the PCIOL group (P < 0.001). Overall, 9 eyes (22%) developed posterior air/gas migration, which occurred more frequently in the SFIOL group than in the PCIOL group (63.7% vs. 6.7%, p < 0.001). Air/gas migration was significantly associated with larger pupil diameter and prior PPV (p = 0.013 and p = 0.014, respectively).

Conclusion

Posterior air/gas migration into the vitreous cavity appears to be an important contributor to graft detachment following DMEK. In this cohort, SFIOL implantation was strongly associated with postoperative air/gas migration. Larger pupil diameter and prior PPV were also significantly associated with air/gas migration.

Background

Descemet membrane endothelial keratoplasty (DMEK) has become the gold standard surgical technique for the treatment of primary and secondary corneal endothelial disorders including fuchs endothelial dystrophy, posterior polymorphous corneal dystrophy, and pseudophakic bullous keratopathy [1]. The procedure involves selective replacement of the recipient’s Descemet’s membrane and corneal endothelium with a healthy donor graft.

DMEK offers several advantages over penetrating keratoplasty (PK), such as minimal invasiveness, faster visual recovery, excellent uncorrected and corrected visual acuity, and reduced postoperative astigmatism [2, 3]. Compared with Descemet stripping automated endothelial keratoplasty (DSAEK), DMEK is associated with better visual outcomes, lower rejection rates, and minimal alteration of the posterior corneal stroma [4, 5].

Stable adhesion of the donor graft is considered essential for successful DMEK surgery [6, 7]. The graft should be precisely centered during implantation, which may reduce the risk of graft detachment [8, 9]. Off-center placement may be associated with the graft lying over the patient’s residual Descemet membrane, potentially increasing the risk of graft detachment [10]. Studies have reported that eyes with graft detachment often require rebubbling of the anterior chamber with air or gas to achieve re-attachment [11]. However, repeated rebubbling in the anterior chamber may further reduce endothelial cell density and potentially increase the risk of long-term graft failure [12, 13].

In addition to accurate graft positioning, the efficacy of intracameral air or gas tamponade appears to be an important factor associated with early graft adherence in the early postoperative period. Previous studies have demonstrated that intracameral air or gas may migrate into the vitreous cavity, particularly in eyes with compromised anterior-posterior segment integrity such as those with prior vitrectomy, iris defects, or inadequate capsular support [14, 15]. The loss of air from the anterior chamber may reduce the tamponade effect and may be associated with a higher likelihood of postoperative graft detachment. Nevertheless, the contribution of posterior migration of air/gas into the vitreous cavity to graft detachment following DMEK has not been systematically investigated.

This study aimed to evaluate postoperative air/gas migration into the vitreous cavity after DMEK, to identify factors associated with this finding, and to assess its clinical outcomes.

Materials and methods

The primary outcome of this study was posterior migration of intracameral air/gas into the vitreous cavity after DMEK. Secondary outcomes included graft detachment, rebubbling requirement, and postoperative best-corrected visual acuity (BCVA).

Study design and patient selection

This single-center retrospective case series included patients who underwent DMEK at the Gazi University Faculty of Medicine between January 2022 and January 2025. The study adhered to the tenets of the Declaration of Helsinki and was approved by the Gazi University Local Ethics Committee (Approval No: 2025 − 1646, Date: 23 September 2025). Written informed consent was obtained from all the participants.

We included 30 eyes of patients with posterior chamber intraocular lenses (PCIOLs) and 11 eyes of patients with scleral-fixated intraocular lenses (SFIOLs); DMEK was performed in all eyes. All analyses were performed on a per-eye basis. Only one eye per patient was included, and bilateral cases were excluded to avoid inter-eye correlation. For each patient, preoperative parameters potentially associated with posterior migration of the intraocular air/gas, such as the type of intraocular lens, anterior chamber depth (ACD), pupil diameter, intraocular pressure (IOP), history of pars plana vitrectomy (PPV), and presence of iris defects, were recorded. Uncorrected and corrected visual acuity were assessed preoperatively and postoperatively in all patients. The presence of graft detachment and the need for subsequent rebubbling were noted on the postoperative day on which each event occurred.

As most patients were referred from external centers, reliable information regarding prior anterior vitrectomy and detailed intraocular lenses (IOL) characteristics (beyond classification as PCIOL or SFIOL) could not be consistently obtained. Preoperative ACD and pupil diameter were measured using Scheimpflug-based corneal tomography (Sirius; CSO, Florence, Italy). Preoperative endothelial cell density could not be reliably measured in all cases because of advanced endothelial dysfunction. BCVA was measured in decimal units and converted to logarithm of the minimum angle of resolution (logMAR) values for statistical analysis.

Eyes with a history of prior corneal surgery, including PK, DSAEK, DMEK, or refractive corneal procedures [photorefractive keratectomy (PRK) / laser in situ keratomileusis (LASIK) etc.] were excluded. Eyes with endothelial failure secondary to ocular trauma were also excluded. In addition, cases undergoing combined procedures at the time of DMEK (e.g., DMEK combined with intraocular lens exchange and/or PPV) were excluded. The use of topical medications, including antibiotics, corticosteroids, and glaucoma drops, was not considered an exclusion criterion. However, patients receiving systemic medications or treatments known to affect the cornea or ocular surface were excluded.

Surgical technique and postoperative follow-up

All DMEK procedures were performed by two experienced surgeons under general anesthesia using the same standardized surgical technique. A peripheral iridectomy was performed at the 6 o’clock position prior to the removal of the recipient Descemet membrane. Standard upper temporal and upper nasal ports were created. The recipient Descemet membrane–endothelial complex was completely stripped and removed through a 2.8-mm clear corneal incision. Donor tissue was stained with 0.06% trypan blue (Membrane Blue^®, DORC, Exeter, NH) and trephined to a diameter of 8.0–8.25 mm (Barron Cornea Donor Button Punch, Katena Products, Inc., Denville, NJ, USA). The donor Descemet’s membrane was injected into the anterior chamber using a dedicated injector (DORC, Zuidland, Netherlands). Graft orientation was confirmed using the Moutsouris sign [16], followed by gentle unfolding and centration of the graft. In eyes with a deep anterior chamber, graft unfolding was facilitated using the C-Press technique as previously described [17]. After correct positioning, a 100% air tamponade was applied for 1 min, after which the anterior chamber was filled with a 20% sulfur hexafluoride (SF₆) gas–air mixture covering approximately 70% of anterior chamber volume.

During the first postoperative week, patients were advised to maintain supine positioning as much as possible. Postoperative positioning was identical in both SFIOL and PCIOL groups, with all patients instructed to maintain a supine position during the early postoperative period. All patients were prescribed topical moxifloxacin 0.5% and dexamethasone sodium phosphate 0.1% four times daily with subsequent tapering based on clinical response.

Patients without complications were examined on postoperative days 1, 2, 3, and 7 and at months 1, 2, and 3. Eyes with air or gas migration into the vitreous cavity and/or graft detachment were examined more frequently. Graft detachment was defined as non-adhesion of any part of the graft, documented by slit-lamp photography (Fig. 1a) and/or anterior segment optical coherence tomography (AS-OCT) (Heidelberg Engineering, Heidelberg, Germany) (Fig. 1b). If more than 10% of the graft was detached, rebubbling with 20% SF₆ gas was performed under sterile conditions in the operating room. Patients were instructed to remain in a supine position postoperatively. Air/gas migration into the vitreous cavity was defined as the absence of intracameral air/gas on slit-lamp examination in the upright position, together with ultrasonographic confirmation of air bubbles in the vitreous cavity (Fig. 1c) starting from postoperative day one. In the supine position, air/gas bubbles were observed around and posterior to the IOL (Fig. 1d). Patients were monitored until graft reattachment was confirmed clinically and/or by AS-OCT (Fig. 2a and b).

Fig. 1.

Absence of air/gas in anterior chamber with associated descemet separation on postoperative day 2. (a) Absence of the air/gas in anterior chamber and corneal edema due to descemet’s detachment while the patient in erect position (b) Descemet’s detachment in anterior segment optical coherence tomography (AS-OCT) image, (c) Ultrasonic confirmation of air bubble in the vitreous cavity (d) Reappearance of air/gas around and behind the intraocular lens (IOL) while the patient in supine position

Fig. 2.

Successful graft attachment following rebubbling. (a) Anterior segment photography (b) Anterior segment optical coherence tomography (AS-OCT) image confirming graft attachment

Statistical analysis

Data were collected by two independent reviewers using a standardized case report form, and discrepancies were resolved by consensus. Statistical analyses were performed using SPSS for Windows, version 17.0 (IBM Corp., Armonk, NY, USA). Continuous variables are expressed as mean ± standard deviation, and categorical variables as counts and percentages. Normality of data distribution was assessed using the Shapiro–Wilk test. Between-group comparisons were performed using the Independent Samples t-test or Mann–Whitney U test, as appropriate. Paired preoperative and postoperative data were analyzed using the Wilcoxon signed-rank test, and categorical variables were compared using Fisher’s exact test. Odds ratios (OR) and risk ratios (RR) with 95% confidence intervals (CI) were calculated to assess the association between potential risk factors and outcomes. Statistical significance was set at P < 0.05.

Results

Several variables are reported in both tables. Table 1 presents intergroup comparisons stratified by IOL type, whereas Table 2 focuses on factors associated with air/gas migration, thereby addressing different clinical questions.

Table 1.

Baseline demographic and clinical characteristics of the study groups

Parameter	PCIOL (n = 30)	SFIOL (n = 11)	p Value
Age	70.70 ± 11.93	64.00 ± 10.10	0.106
Gender (F/M)	16/14	0/11	0.001*
Pupil Diameter	3.03 ± 0.51	3.82 ± 0.44	< 0.001*
ACD	3.15 ± 0.36	3.31 ± 0.35	0.206
IOP	13.96 ± 3.01	15.54 ± 2.25	0.097
Preoperative BCVA	2.02 ± 0.77	1.91 ± 0.84	0.608
Postoperative BCVA	0.54 ± 0.48	0.79 ± 0.47	0.081
Air/Gas Migration	2 (6.7%)	7 (63.7%)	< 0,001*
Rebubbling	3 (10%)	5 (45.5%)	0.021*
Posterior Vitrectomy	3 (10%)	6 (54.6%)	0.006*
Iris Defect	1	1	0.470

Values are presented as mean ± standard deviation (SD) or number (%)

PCIOL: Posterior chamber intraocular lens; SFIOL: Scleral fixated intraocular lens

ACD: Anterior chamber depth; IOP: Intraocular pressure; BCVA: Best-corrected visual acuity

Statistical significance was set at P < 0.05

Table 2.

Baseline demographic and clinical characteristics stratified by air/gas dislocation

Parameter	Air/Gas Migration (+) (n = 9)	Air/Gas Migration (-) (n = 32)	p Value
Age	68.77 ± 7.83	68.93 ± 12.72	0.972
Gender (F/M)	2/7	15/17	0.262
Pupil Diameter	3.67 ± 0.70	3.12 ± 0.52	0.013*
ACD	3.25 ± 0.28	3.18 ± 0.38	0.629
IOP	15.44 ± 2.12	14.09 ± 3.03	0.220
Preoperative BCVA	2.11 ± 1.02	1.96 ± 0.71	0.769
Postoperative BCVA	0.87 ± 0.54	0.54 ± 0.45	0.086
Posterior Vitrectomy (Y/N)	5/4	4/28	0.014*
Iris Defect (Y/N)	0/9	2/30	1
Rebubbling	6 (66.7%)	2 (6.3%)	< 0.001*

Values are presented as mean ± standard deviation (SD) or number (%)

ACD: Anterior chamber depth; IOP: Intraocular pressure; BCVA: Best-corrected visual acuity

Statistical significance was set at P < 0.05

A total of 41 eyes were analyzed (30 PCIOL and 11 SFIOL). Although the percentage of male patients was substantially higher in the SFIOL group (p = 0.001), there was no significant difference in age between the groups (p = 0.106). The mean pupil diameter was larger in the SFIOL group (3.82 ± 0.44 mm vs. 3.03 ± 0.51 mm, p < 0.001). The ACD, IOP, and preoperative BCVA did not significantly differ between the groups (p > 0.05). Postoperative BCVA tended to be worse in the SFIOL group, although this difference was not statistically significant (p = 0.081). Air/gas migration was observed in 9 eyes (22%) and was significantly more frequent in the SFIOL group than in the PCIOL group (63.7% vs. 6.7%, p < 0.001). Rebubbling was required in 8 eyes (19.6%) and was significantly more frequent in the SFIOL group (45.5% vs. 10.0%, p = 0.022). A history of posterior vitrectomy was significantly more frequent in the SFIOL group (54.6% vs. 10.0%, p = 0.006). Iris defects were rare and showed no significant intergroup differences (P = 0.470) (Table 1).

Air/gas migration was observed in 9 (22%) of the 41 eyes, whereas 32 eyes (78%) showed no migration. Age and sex distributions were similar between the air/gas migration -positive and -negative groups (p = 0.972 and p = 0.262, respectively). Pupil diameter was significantly larger in the air/gas migration-positive group than in the air/gas migration-negative group (3.67 ± 0.70 mm vs. 3.12 ± 0.52 mm; p = 0.013). ACD, IOP, and preoperative and postoperative BCVA did not significantly differ across the groups (p > 0.05). Air/gas migration was significantly associated with a history of posterior vitrectomy (p = 0.014). Iris defects were rare and did not differ significantly between the two groups (p = 1.000). Among the 9 eyes with air/gas migration, 6 eyes required rebubbling, whereas 3 eyes did not require additional intervention. In the air/gas migration -negative group, 2 of 32 eyes required rebubbling, while 30 eyes did not require any additional intervention (p < 0.001) (Table 2).

Eyes with SFIOL implantation showed a significantly higher risk of air/gas migration compared to those with PCIOL (OR = 24.50, 95% CI: 3.70–161.96; RR = 9.54, 95% CI: 2.32–39.15; p = 0.0009). Posterior vitrectomy was also associated with a significantly increased risk of migration (OR = 10.80, 95% CI: 2.00–58.10; RR = 5.45, 95% CI: 1.64–18.13; p = 0.0056) (Table 3).

Table 3.

Odds ratios and risk ratios for factors associated with air/gas migration

Air/Gas Migration	OR	95% CI	RR		95% CI	P value
SFIOL/PCIOL	24.50	3.70–161.96	9.54		2.32–39.15	0.0009
Posterior Vitrectomy	10.80	2.00–58.10	5.45		1.64–18.1	0.0056

OR: Odds Ratio; RR: Risk Ratio; CI: Confidence Interval. Statistical significance was set at P < 0.05

Eyes with air/gas migration had a significantly higher likelihood of requiring rebubbling compared to those without migration (OR = 30.00, 95% CI: 4.09–219.99; RR = 10.66, 95% CI: 2.58–44.09; p = 0.0008) (Table 4).

Table 4.

Odds ratio and risk ratio for rebubbling according to air/gas migration

Rebubbling	OR	95% CI	RR	95% CI	P value
Air/Gas Migration	30.00	4.09–219.99	10.66	2.58–44.09	0.0008

OR: Odds Ratio; RR: Risk Ratio; CI: Confidence Interval. Statistical significance was set at P < 0.05

Discussion

In our clinical experience, intracameral air or gas injected into the anterior chamber during DMEK surgery may occasionally migrate into the vitreous cavity and may be associated with subsequent graft detachment. This observation prompted us to investigate the potential predisposing factors for air/gas migration and subsequent graft detachment, particularly in eyes with prior SFIOL or PCIOL implantation, where anatomical alterations may interfere with graft adhesion.

Despite being increasingly adopted worldwide, DMEK remains a technically demanding procedure with a steep learning curve even for experienced corneal surgeons. Several DMEK-specific complications have been described in the literature, including incomplete donor endothelial harvesting, donor tissue damage during insertion, incomplete recipient Descemet membrane stripping, pupillary block following gas injection, posterior migration of the gas, and graft detachment [18–20]. Graft detachment requiring rebubbling is one of the most common postoperative complications, typically occurring within the first postoperative week. Factors that have been associated with graft detachment include posterior migration of the gas, endothelial dysfunction, insufficient tamponade duration, and inadequate adhesion forces at the donor–recipient interface [20, 21].

In our study, posterior migration of the air/gas was significantly associated factor associated with graft detachment after DMEK. The eyes in the SFIOL group exhibited a significantly higher rate of air/gas migration than those in the PCIOL group (OR = 24.50; RR = 9.54; p = 0.0009). Eyes with SFIOL implantation often more complex, frequently characterized by prior vitrectomy, compromised capsular support, iris defects, and altered anterior–posterior segment anatomy. Therefore, SFIOL implantation itself may not be an isolated causal factor, but rather a surrogate marker of overall anatomic complexity that predisposes to posterior air/gas migration. The higher migration rate in SFIOL eyes may reflect structural alterations, including zonular loss, disruption of the iris–lens diaphragm, and altered spatial relationships between the iris and IOL optic. However, these anatomical and biomechanical mechanisms were not directly evaluated in the present study and should be interpreted as possible explanations. In addition, certain design characteristics of SFIOL, including smaller optic diameters and thinner haptics, might offer less effective resistance against posterior air/gas passage, potentially facilitating migration into the vitreous cavity. When compared with previous reports on DMEK in complex eyes, the rate of posterior air/gas migration observed in our SFIOL group appears higher than that generally reported in standard pseudophakic or vitrectomized populations [22, 23]. However, published data specifically focusing on SFIOL-implanted eyes are limited. Therefore, our findings may indicate that SFIOL eyes represent a particularly high-risk subgroup within surgically complex cases rather than a broadly comparable population.

Following donor lenticule insertion into the anterior chamber, the graft generally remained stable until an air bubble was injected beneath the endothelium. This stability may be related to the relatively small anterior chamber fluid volume, low intraocular turbulence, and formation of a closed system after corneal wound suturing. However, in eyes with a deep anterior chamber, increased fluid volume and turbulence may facilitate excessive graft mobility and hinder graft adhesion [24]. Pralits et al. demonstrated that in phakic eyes with an ACD of ≤ 3 mm, the graft is fully covered by gas and is less sensitive to patient positioning. In contrast, in pseudophakic eyes with larger ACD values, graft adhesion is more dependent on gas filling and patient position, with positional effects becoming increasingly important as the ACD increases [22]. Consistent with these findings, our study demonstrated a higher incidence of air/gas migration in eyes with deeper ACD (although not statistically significant). Consequently, recognition of deeper ACD as a potential risk factor may help guide perioperative management and may reduce the likelihood of postoperative graft detachment.

Pupil diameter was another important factor in our cohort. Patients in the SFIOL group exhibited significantly larger pupils than those in the PCIOL group (p < 0.001), and the pupils were also significantly larger in the eyes with air/gas migration (p = 0.013). These findings suggest that eyes with traumatic mydriasis, and prior complicated cataract surgery may be particularly susceptible to air/gas migration and subsequent graft detachment, underscoring the importance of careful postoperative monitoring in such cases. Postoperative iris–lens diaphragm defects, even if subtle, may allow gas to migrate into the vitreous cavity, potentially resulting in reduced tamponade and a higher likelihood of graft detachment and rebubbling. Therefore, adequate iris tissue may be important to maintain effective tamponade. In our series, two patients had limited iris defects involving two clock hours: neither developed air/gas migration, graft detachment, nor required rebubbling, possibly due to the restricted extent of the defect and the presence of PCIOL implantation.

Reported rebubbling rates after DMEK vary widely in the literature, with some studies reporting rates as high as 76–82% [25]. A recent comprehensive review estimated an average rebubbling rate of approximately 29% [26]. Evidence indicates that both graft detachment [27] and rebubbling [28] rates improve with increasing surgical experience. Our center has over 10 years of experience in DMEK and performs approximately 50 DMEK procedures annually. Notably, 66.7% of patients with air/gas migration into the vitreous cavity required rebubbling, indicating that, while air/gas migration was strongly associated with graft detachment and the need for rebubbling, not all cases of air/gas migration inevitably necessitate graft detachment and rebubbling. Air/gas migration was strongly associated with the need for rebubbling (OR = 30.00; RR = 10.66; p = 0.0008). Postoperative BCVA did not differ significantly between groups, suggesting that posterior air/gas migration may primarily influence early postoperative management rather than final visual outcomes in this cohort.

55.6% of eyes with air/gas migration into the vitreous had a history of prior vitrectomy, and previous vitrectomy was significantly associated with air/gas migration (OR = 10.80; RR = 5.45; p = 0.0056). Eyes with prior vitrectomy present a more complex intraoperative environment owing to the absence of posterior vitreous support, deeper anterior chambers, and increased mobility of the iris-lens diaphragm [29]. In such eyes, air bubbles may displace the diaphragm posteriorly rather than tamponade the graft, potentially contributing to air/gas migration and subsequent graft detachment. Furthermore, posterior migration of the air/gas may be associated with complications such as iridocorneal adhesions, severe ocular hypertension, and mechanical stress at IOL fixation sites, particularly in SFIOL-implanted eyes [30]. Air or gas pressure exerted on the IOL surface may compromise lens stability, particularly in the early postoperative period, potentially leading to subluxation or dislocation. Sorkin et al. [23] proposed pars plana infusion to stabilize the anterior segment in vitrectomized eyes during DMEK; however, this technique carries additional risks including retinal tears and retinal detachment. Given these potential complications, we prefer not to employ pars plana infusion even in high-risk eyes. These mechanisms remain hypothetical and should be interpreted as potential explanations rather than confirmed causal pathways.

This study had several limitations. First, the small sample size limits statistical power. Second, selection bias and limited control of confounding factors could have been introduced by a retrospective approach. Third, although the same surgical technique was used, the procedures were performed by two different surgeons, which may have introduced inter-surgeon variability. In addition, the imbalance in prior vitrectomy rates between the PCIOL and SFIOL groups may have introduced confounding. Due to the limited number of migration events, a robust multivariable regression analysis could not be reliably performed. Finally, larger prospective studies and longer follow-up periods are needed to validate these results and clarify factors associated with posterior air/gas migration after DMEK surgery.

Postoperative positioning remains controversial. While strict supine positioning for 48 h has not been shown to significantly reduce graft detachment compared to unassisted care, graft detachment may still occur after gas absorption, typically between 48 and 72 h postoperatively [31, 32]. Mathematical models and clinical studies suggest that graft detachment in shallow anterior chambers is more sensitive to air/gas fill, whereas patient positioning plays a more critical role in deep anterior chambers [22, 33]. Although postoperative positioning was not specifically evaluated in the present study, our findings suggest that prolonged supine positioning could be considered as a practical measure in anatomically high-risk eyes (e.g., eyes with SFIOL implantation, prior vitrectomy, larger pupil diameter, or deeper ACD) to potentially reduce posterior air/gas migration and subsequent graft detachment. Further prospective studies are needed to clarify the optimal positioning strategy in these subgroups.

In conclusion, posterior air/gas migration into the vitreous cavity appears to be an important contributor to graft detachment after DMEK. In our cohort, SFIOL implantation was associated with a higher rate of postoperative air/gas migration. Other variables significantly associated with air/gas migration included prior vitrectomy and larger pupil diameter. Recognition of these high-risk features, including the tamponade strategy and postoperative positioning, may be important for optimizing perioperative management.

Abbreviations

DMEK

Descemet membrane endothelial keratoplasty

PCIOL

Posterior chamber intraocular lenses and

SFIOL

Scleral-fixated intraocular lenses

ACD

Anterior chamber depth

IOP

Intraocular pressure

IOL

Intraocular lenses

LogMAR

Logarithm of the minimum angle of resolution

PPV

Pars plana vitrectomy

BCVA

Best corrected visual acuity

PRK

Photorefractive keratectomy

LASIK

Laser in situ keratomileusis

PK

Penetrating keratoplasty

DSAEK

Descemet stripping automated endothelial keratoplasty

SF₆

Sulfur hexafluoride

AS-OCT

Anterior segment optical coherence tomography

OR

Odds Ratio

RR

Risk Ratio

CI

Confidence Interval

Author contributions

EA and BA designed the study. EA collected the clinical data, performed the statistical analysis, interpreted the data, and drafted the manuscript. BA contributed to drafting the manuscript and was involved in surgical procedures and patient management. MCO and RFA contributed to surgical procedures and patient management. VCY collected the clinical data. CEB collected the clinical data and contributed to drafting the manuscript. EG performed the statistical analysis and interpreted the data. All authors read and approved the final manuscript.

Funding

No funding was received for conducting this study.

Data availability

The datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

This study was approved by the Institutional Review Board/Ethics Committee of the Gazi University Local Ethics Committee (Approval No: 2025 − 1646). Written informed consent was obtained from all the participants.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.