Eyelid edema reduction following blepharoplasty: a 3D imaging-based pilot study on the efficacy of Hilotherapy

Abstract

Background

Eyelid edema is a frequent and distressing early complication of upper blepharoplasty, yet optimal postoperative management remains unsettled. Conventional cryotherapy (e.g., ice packs, cooling masks) provides unstable temperatures and can cause adverse effects. Systemic anti-inflammatory drugs are not suitable for all patients. Hilotherapy provides constant, precisely controlled cooling and has reduced swelling in maxillofacial surgery. Its value in eyelid procedures is unknown. This study used three-dimensional (3D) stereophotography to objectively quantify periocular changes and evaluate whether Hilotherapy reduces early postoperative eyelid edema after upper blepharoplasty.

Methods

Twenty-three patients with symmetrical bilateral dermatochalasis (46 eyes) undergoing upper eyelid blepharoplasty under local anesthesia were enrolled. Surgery was performed simultaneously on both eyelids by two experienced surgeons using an identical technique. Hilotherapy was applied to one randomly assigned eye, with the contralateral eye serving as an untreated control. Eyelid edema was assessed using 3D stereophotography at four time points: immediately after treatment (T0), 24 hours (T1), 2 weeks (T2), and 3 months (T3) postoperatively.

Results

Of the 23 patients (9 males, 14 females; mean age 65 years), 16 (69.6%) showed reduced swelling with Hilotherapy at T0, 15 (65.2%) at T1, and 13 (56.5%) at T2. In the treatment group, males had significantly more eyelid swelling than females at T0 (1.216±0.655 vs. 0.665±0.667 cm², P=0.023), but this difference was not significant at T1 (1.343±0.579 vs. 1.019±0.784 cm², P=0.166) or T2 (0.474±0.573 vs. 0.354±0.342 cm², P=0.801). Compared to controls, the swelling was significantly lower in the treated eyelids at T0 (0.880±0.715 vs. 1.129±0.915 cm², P=0.026) and T1 (1.146±0.728 vs. 1.399±1.059 cm², P=0.042), indicating that Hilotherapy effectively reduces early postoperative eyelid edema.

Conclusions

Hilotherapy is a well-tolerated and effective method for reducing postoperative eyelid edema in the early days following upper eyelid blepharoplasty. It may enhance postoperative care not only in blepharoplasty but potentially in eyelid surgery overall.

Introduction

Eyelid edema is one of the most common postoperative complaints following eyelid surgery, particularly during the first postoperative weeks when it is most distressing to patients (1). It can induce pain, impair vision, and negatively impact both physical and mental well-being (1,2). Consequently, effective management of postoperative edema remains a key clinical concern.

Cooling therapy is widely employed to mitigate eyelid edema, with conventional methods including ice packs, cold patch masks, and cooling water rinses (3,4). However, their effectiveness remains debated, and these approaches present notable limitations, such as difficulty in maintaining a stable cooling effect and risks like frostbite (5). Pharmacological interventions, such as corticosteroids and non-steroidal anti-inflammatory drugs, help reduce postoperative edema and pain (6). However, they are not the ideal solution due to potential systemic side effects and contraindications in patients with conditions like peptic ulcers, kidney failure, diabetes, glaucoma, or liver dysfunction (6).

Hilotherapy is an emerging cooling technique that utilizes a temperature-controlled device comprising a cooling unit and a pre-shaped mask (7-11). This system ensures a consistent temperature range (10 to 35 ℃) by circulating water through the mask, allowing precise regulation of cooling effects. Hilotherapy has already demonstrated efficacy in maxillofacial procedures (7-11). However, its role in reducing postoperative eyelid edema following blepharoplasty remains unexplored.

Recent advances in high-resolution camera technology have facilitated the use of three-dimensional (3D) imaging for facial and periocular morphological analyses (12-23). These noninvasive 3D imaging techniques provide rapid and highly precise assessments to quantify changes in the periocular region (12-23). Previous studies have already validated the reliability and accuracy of this novel 3D imaging technique in periocular measurements using the 3D VECTRA M3 system (Canfield Scientific, Inc., Fairfield, NJ, USA), highlighting its significant potential for broader applications in ophthalmic plastic and reconstructive surgery (12-23). In addition, compared to conventional two-dimensional (2D) imaging methods, 3D stereophotogrammetry offers superior accuracy (14-23). Although 3D reconstruction techniques are theoretically capable of measuring both surface area and volume, previous studies have demonstrated that current stereophotogrammetry lacks sufficient repeatability and accuracy for upper eyelid volume assessment. In contrast, measurements of upper eyelid area have shown excellent reliability (22-25). As the area derived from 3D imaging reflects a depth-resolved 3D parameter, it may serve as a robust surrogate for volume in quantifying postoperative eyelid edema.

Therefore, this study aims to evaluate the efficacy of Hilotherapy in reducing eyelid edema following upper blepharoplasty, to objectively assess changes in eyelid swelling over time, and to optimize postoperative management for eyelid surgery patients using the latest 3D imaging techniques. We present this article in accordance with the STROBE reporting checklist (available at https://qims.amegroups.com/article/view/10.21037/qims-2025-832/rc).

Methods

Participants

Patients diagnosed with symmetrical bilateral dermatochalasis who underwent bilateral blepharoplasty at the University of Cologne between July 2019 and November 2020 were enrolled. Exclusion criteria included asymmetrical dermatochalasis, glaucoma, inflammatory eye diseases, mental illness, diabetes, substance abuse, Raynaud syndrome, facial wounds, and prior facial or eyelid surgery. This study adhered to the Declaration of Helsinki and its subsequent amendments. Ethical approval was granted by the institutional ethics board of the University of Cologne (No. 17-444). Written informed consent was obtained from all participants, including consent for the use of their photographs.

Blepharoplasty

All patients underwent bilateral blepharoplasty in a single surgical session under local anesthesia. The procedure was performed simultaneously on both eyelids by two experienced surgeons using an identical surgical technique. The assignment of eyelid surgery to each surgeon was randomized to minimize bias. Standardized surgical guidelines were followed, ensuring symmetrical tissue removal from both sides.

Hilotherapy protocol

Patients were randomly assigned to two groups. In Group A, Hilotherapy was applied to the right eye immediately post-surgery, while in Group B, the left eye received treatment. The untreated contralateral eye served as a control. A unilateral Hilotherm mask (Figure 1, Hilotherm GmbH, Argenbühl-Eisenharz, Germany) was applied for one hour at a controlled temperature of 17 ℃. During the treatment, patients remained seated with their eyes closed. No oral or systemic analgesics were administered postoperatively.

Figure 1.

Hilotherapy device and clinical application. (A) Cooling control unit with pre-shaped periocular mask. (B) Patient receiving unilateral Hilotherapy after upper blepharoplasty. This image is published with the patient’s consent.

3D photographs

Standardized 3D facial photographs were captured at four time points: immediately after Hilotherapy (T0), 24 hours (T1), 2 weeks (T2), and 3 months (T3) postoperatively. All images were taken by the same photographer using a 3D VECTRA M3 system (Canfield Scientific, Inc., Fairfield, NJ, USA). The 3D VECTRA M3 system was calibrated before each session to ensure consistency in imaging.

Data analyses

Periocular landmarks were identified, labelled, and targeted areas were measured (Figure 2). The measured region encompassed the space between the lower margin of the eyebrow and the upper margin of the upper eyelid, as well as the horizontal span between the endocanthion and exocanthion, and the vertical alignment of the eyebrow’s head and tail.

Figure 2.

Eyelid area measurements. Eyelid area delineation on 3D stereophotographs used to quantify postoperative edema. This image is published with the patient’s consent. 3D, three-dimensional.

Eyelid area values at T3 (3 months postoperatively) were used as the baseline for comparison with earlier time points (T0, T1, and T2). The relative increase in eyelid area at each time point was calculated for both the treatment and control groups. Treatment efficacy was determined if the increase in eyelid area was 5% smaller in the treatment group compared to the control group. To minimize analytical bias, factors such as preexisting or postoperative asymmetry in brow and eyelid creases and significant eyebrow changes (e.g., shedding) were carefully considered and excluded from analysis when necessary.

Postoperative care

Following surgery, photographs, and Hilotherapy, patients were advised to refrain from lifting heavy weights and using anticoagulants. A postoperative regimen included ocular lubricating drops five times daily and topical antibacterial ointment three times daily for 2 weeks.

Statistical analysis

Statistical analyses were conducted using SPSS version 22.0 (IBM Corporation, Armonk, NY, USA). Group differences were assessed using an independent samples t-test or the Mann-Whitney U test, depending on data distribution, which was determined using the Kolmogorov-Smirnov test. Statistical significance was set at P<0.05.

Results

Study population

A total of 23 patients (46 eyes) were recruited from the Department of Ophthalmology, University of Cologne. The cohort included nine males (aged 49–81 years, mean 64 years) and 14 females (aged 51–81 years, mean 65 years). There was no significant difference in age between male and female participants (P=0.967, independent samples t-test).

Treatment efficacy of Hilotherapy

Among the 23 patients, 16 (69.6%) exhibited a positive response to Hilotherapy with less swelling at T0, decreased to 15 (65.2%) at T1, and to 13 (56.5%) at T2. Females demonstrated a higher response with less swelling rates than males, particularly at T0 (78.6% vs. 55.6%), but by T1 and T2, response rates between genders had converged (64.3% vs. 66.7% and 50.0% vs. 66.7%; Table 1).

Table 1. Eyelid area changes following blepharoplasty: comparison between Hilotherapy-treated and control eyes.

Variable	Time-point
	T0	T1	T2
Patients with positive effects in the Hilotherapy group
Male	5/9 (55.6)	6/9 (66.7)	6/9 (66.7)
Female	11/14 (78.6)	9/14 (64.3)	7/14 (50.0)
All patients	16/23 (69.6)	15/23 (65.2)	13/23 (56.5)
Increased eyelid area in the treatment group (cm2)
Males	1.216±0.655	1.343±0.579	0.474±0.573
Females	0.665±0.667	1.019±0.784	0.354±0.342
P	0.023*	0.166	0.801
Increased eyelid area in the control group (cm2)
Males	1.324±0.977	1.502±1.269	0.715±0.595
Females	1.003±0.849	1.333±0.892	0.376±0.233
P	0.378	0.614	0.284
Increased eyelid area in the Hilotherapy vs. the control group (cm2)
Treatment group	0.880±0.715	1.146±0.728	0.405±0.448
Control group	1.129±0.915	1.399±1.059	0.447±0.315
Difference	0.249±0.488	0.253±0.691	0.042±0.304
P	0.026*	0.042*	0.378
Increased area of eyelid in patients with positive effect in the treatment (cm2)
Male	1.356±0.950	1.475±0.662	0.207±0.155
Female	0.561±0.501	0.975±0.596	0.140±0.107
P	0.062	0.195	0.391

Data are presented as n/N (%) or mean ± SD. *, P<0.05. SD, standard deviation; T0, immediately post-treatment; T1, 24 h post-treatment; T2, 2 weeks post-treatment.

Eyelid area changes

In the treatment group, males exhibited a significantly greater increase in eyelid swelling than females immediately after Hilotherapy (T0) (P=0.023, Table 1). However, this difference was no longer statistically significant at 24 hours (T1, P=0.166) or 2 weeks post-treatment (T2, P=0.801). The control group followed a similar trend, with males consistently showing greater eyelid swelling increases than females, though the differences remained non-significant (P≥0.284, respectively at all time points). Compared to the control group, eyelid swelling in the treatment group was significantly reduced at T0 (P=0.026) and T1 (P=0.042), showing that Hilotherapy effectively reduces swelling in the early postoperative period (Figure 3). By T2, however, this benefit was no longer significant (P=0.378).

Figure 3.

Eyelid changes directly after upper eyelid blepharoplasty (T0), 1 day (T1), and 2 weeks after surgery (T2). *, P<0.05 for the difference between Group 1 and Group 2.

Influence of age and gender on the effect rates of Hilotherapy after blepharoplasty

In males, younger patients appeared to respond more favorably to Hilotherapy following upper eyelid blepharoplasty; however, these differences were not statistically significant at any time point (Table 2; P≥0.221, respectively). Among female patients, those demonstrating an effect at T0 and T2 were slightly older, whereas at T1, responders were marginally younger than non-responders. Nonetheless, neither age nor gender had a statistically significant influence on the effect rates of Hilotherapy (P≥0.221, respectively).

Table 2. Influence of age and gender on the effect rates of Hilotherapy after blepharoplasty.

Variable	Time-point
	T0	T1	T2
Age of male patients in the treatment group (years)
Male patients with effect	59.2±7.2	62.0±9.4	61.5±9.2
Male patients without effect	70.0±10.1	68.0±11.4	69.0±10.8
P	0.221	0.606	0.302
Age of female patients in the treatment group (years)
Female patients with effect	64.7±8.1	63.9±7.5	65.0±7.0
Female patients without effect	63.7±15.1	65.6±12.9	64.0±11.7
P	0.583	0.84	0.797
Age of all patients (years)
Patients with effect	62.9±7.8	63.1±8.0	63.4±7.9
Patients without effect	67.6±12.1	66.5±11.6	65.5±11.1
P	0.503	0.771	0.597

Data are presented as mean ± SD. SD, standard deviation; T0, immediately post-treatment; T1, 24 h post-treatment; T2, 2 weeks post-treatment.

Discussion

Until today, the role of localized cooling in postoperative edema management remains controversial. While some studies have reported beneficial effects of cryotherapy in reducing swelling, others have failed to demonstrate significant improvements (26-30). Shin et al. documented positive effects of cryotherapy in patients undergoing craniotomy using cold gel packs, whereas studies on postoperative swelling following third molar extraction found no significant benefit from cryotherapy (27,28). A study by Pool et al. evaluating ice pack cooling after blepharoplasty also did not find a significant reduction in eyelid edema (26). However, methodological limitations such as the use of subjective scoring and fluctuating temperatures may have affected the results of these studies (26). In contrast, Hilotherapy provides a more controlled cooling method than conventional approaches, which often lack temperature stability. Rana et al. compared Hilotherapy to cold compresses in mandibular fracture patients, applying Hilotherapy at 15 ℃ for 12 hours daily over three postoperative days, resulting in a significant reduction in swelling (11). Similarly, Hilotherapy has been shown to effectively reduce postoperative edema in orthognathic surgery with significant reductions in swelling compared to conventional cooling methods (29,30). Compared to previous studies (in eyelid surgery), this study addressed these key influencing factors by using the Hilotherapy device to improve temperature stability and employing the latest 3D imaging for a more consistent and objective approach.

The physiological basis of Hilotherapy efficacy lies in its ability to induce vasoconstriction, thereby reducing tissue perfusion, inflammation, and swelling (11). Cryotherapy in general has been shown to slow biochemical reactions, decrease inflammatory responses, and reduce peripheral nerve conduction, which may also contribute to pain relief (3,11). Studies suggest that 15 ℃ is the optimal temperature for maximizing vasoconstriction (3,31). However, preliminary examinations for this study indicated that this lower temperature was intolerable for many patients. Therefore, a compromise temperature of 17 ℃ was selected in this study, providing effective anti-edema benefits while minimizing patient discomfort during cooling. Importantly, lower temperatures may pose risks such as tissue injury, lymphatic impairment, and microcirculatory disturbances, reinforcing the importance of identifying a safe and effective cooling threshold.

The results of this study indicate that Hilotherapy at 17 ℃ is effective in reducing postoperative eyelid edema in the days following upper eyelid blepharoplasty. In addition, this study revealed significant gender-based differences in response to Hilotherapy. Female patients exhibited a smaller eyelid area increase direct postoperatively than males. This finding may be consistent with the vasodilatory effects of estrogen, which may contribute to an increased vascular responsiveness in females (32). However, the reduced estrogen levels in older women could diminish this effect, potentially explaining the lower efficacy observed in aging populations (32). In contrast, males mostly have higher muscle mass, greater height, and a higher basal metabolic rate, which may contribute to their sensitivity to cold-induced vasoconstriction (33). Nonetheless, neither age nor gender had a statistically significant influence on the effectiveness of Hilotherapy.

Previous research suggests that postoperative swelling typically peaks between 24 and 72 hours (34). Our findings align with this, showing that eyelid swelling is more pronounced on the first postoperative day than within the initial 24 hours (35,36). This observation highlights the importance of early postoperative interventions to mitigate edema progression. Future studies should explore the long-term benefits of Hilotherapy beyond the initial 24-hour period to assess its impact on overall recovery.

Although our study used an objective measurement approach, some limitations remain. This pilot study did not include a conventional cold compress comparator. The ethics committee did not approve a bilateral design, as they were concerned that alternating treatments on paired eyelids could result in postoperative asymmetry. Therefore, future studies will further compare Hilotherapy with conventional ice packs for reducing eyelid edema. The measurement area covered most but not all of the swollen eyelid region, potentially underestimating total edema. Additionally, postoperative changes such as eyebrow drooping could have influenced area calculations. Future multicenter studies should incorporate larger sample sizes and extended follow-up periods to further validate these findings. Moreover, investigating patient-reported outcomes, such as comfort and satisfaction, may provide additional insights into the clinical utility of Hilotherapy.

Conclusions

In summary, our findings suggest that Hilotherapy at 17 ℃ is an effective and well-tolerated intervention for reducing postoperative eyelid edema in the first days after upper eyelid blepharoplasty. The results of this study provide valuable insights for optimizing postoperative care and enhancing patient recovery following blepharoplasty. By utilizing the newest 3D imaging techniques, this study offers also a novel and precise evaluation method for periocular edema, setting a foundation for further research in this field and potentially optimizing postoperative management for eyelid surgery patients in general.

Supplementary

The article’s supplementary files as

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the institutional ethics board of the University of Cologne (No. 17-444), and written informed consent was obtained from all individual participants, including consent for the use of their photographs.

Data Sharing Statement

Available at https://qims.amegroups.com/article/view/10.21037/qims-2025-832/dss

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DOI: 10.21037/qims-2025-832