Lower Eyelid Retraction Repair Using Autologous Auricular Scapha Cartilage

doi:10.21203/rs.3.rs-3342465/v1

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Lower Eyelid Retraction Repair Using Autologous Auricular Scapha Cartilage

https://doi.org/10.21203/rs.3.rs-3342465/v1

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Purpose: To evaluate lower eyelid retraction surgery using autologous auricular scapha cartilage (anterior surface groove between helix and anti helix) and present its surgical results in a group of patients.

Methods: Medical records of 21 patients who underwent lower eyelid retraction surgery using scapha cartilage were reviewed. Retractions were longstanding (6 months to 20 years), with 1 mm or more inferior scleral show, and due to previous lower eyelid blepharoplasty, facial palsy or congenital retraction. Lateral canthotomy, cantholysis, subtarsal conjunctiva-lower eyelid retractors incision, lower eyelid retractor lysis and suturing of the cartilage graft to the defect area without conjunctival cover, and tighteneing of the lateral canthal corner were performed in all patients.

Results: Twenty nine eyelids in 21 patients were operated. There were no per-operative complications. During the follow-up period (mean 11 months; range 6-30 months), lower lid retraction improved in 96,5% of eyelids. The mean postoperative margin to refle distance measurements (MRD2) was statistically significantly lower compared with preoperatives (p=0,001; p<0,01). Average MRD2-a (midpupil to lower lid) and MRD2-b (lateral limbus to lower lid) improvements were 1,77±0,80 and 2,04±0,81 respectively (p=0,001; p<0,01).

Four eyelids (4/29) were revised because of canthal corner loosening. All four already had two or more repairs elsewhere and require correction with periosteal flaps. The graft was visible in two lids but revision was not required. One patient had mild donor area helix deformity that did not require futher intervention.

Conclusion: Many lower lid retractions that have no middle or posterior lamellar shortening can be corrected without grafting. However in those cases of lower lid retraction associated with middle/posterior lamella shortening, auricular scapha cartilage spacer graft is useful. Its advantages include ease of harvest with low complication rate at the donor site; being autologous, it is stable and does not shrink; it is softer compared to posterior cartilage and has a concavity that fits well on the globe.

The auricular scapula cartilage emerges as a promising treatment option for lower eyelid retraction resulting from various causes, characterized by its ease of access, effectiveness, cost-efficiency, and low rate of complications.

Lower eyelid retraction can manifest as a normal anatomical variation or occur involutionally due to factors like trauma, post-blepharoplasty, or facial palsy [1]. It can give rise to both cosmetic and functional issues, ranging from ocular discomfort to vision loss [2]. Correcting lower eyelid retraction poses significant challenges, and the treatment approach should be tailored to the underlying cause of the retraction. One commonly employed surgical technique to address mid-posterior lamella shortening and provide support to the lower eyelid is lower eyelid lifting with a spacer graft [3]. Various materials are used for this purpose, such as hard palate mucosa (HPM), ear cartilage, and synthetic/allogenic materials [4]. However, no single graft material can be considered flawless, as each comes with its own set of advantages and disadvantages. The ideal material should possess qualities like appropriate flexibility, compatibility with the eyelid, minimal shrinkage, invisibility from the outside, and reduced donor site complications. In this paper, the author presents surgical outcomes utilizing auricular scapha cartilage grafts as lower eyelid spacers.

This retrospective study reviewed the medical records of 21 patients (29 eyelids) who underwent lower eyelid retraction surgery with scapha cartilage spacer grafts between March 2021 and June 2023. The study was approved by the Institutional Review Board of Emsey Hospital. The patients were selected based on the diagnosis of eyelid retraction and a minimum follow-up period of 6 months. Patients requiring midfacelift and skin grafting due to anterior lamellar defects were excluded from the study. The causes of eyelid retraction were categorized as post-lower eyelid surgery (n=13), facial palsy (n=4), and genetic factors (n=12). Eight patients had bilateral involvement.

Demographic characteristics of the patients, including age and gender, were recorded. Additionally, information on the specific etiology of eyelid retraction, previous surgical histories, and surgical outcomes based on data from other relevant publications were documented. The presence of lower eyelid laxity and middle lamella scarring was clinically assessed. To evaluate eyelid laxity, the snap back test and eyelid distraction test were performed, while middle/posterior lamella scarring was evaluated using the vertical traction test.

All surgical procedures were performed by a single surgeon. Anesthesia was induced under either local sedation or general anesthesia, and lidocaine-bupivacaine was injected subcutaneously and subconjunctivally around the lower eyelid. A 6.0 silk traction suture was placed to aid in manipulation during the surgery. The surgical approach involved lateral canthotomy, cantholysis, incision of the subtarsal conjunctiva, and lower eyelid retractor release along the lateral aspect of the lower lid, adjacent to the punctum. Careful release of lower eyelid retractors and any present scarring was performed to achieve complete mobility of the lower lid.

The scapha cartilage was exposed by making an incision along the helix-scapha border after subcutaneous injection of lidocaine-bupivacaine. A curved strip of cartilage with rounded ends was harvested from the anterior surface of the cartilage (Fig.1). During the harvesting of the cartilage graft, it was considered essential for the scapha cartilage curvature to be in harmony with the globe's convex curvature otherwise, graft would be visible from the outside.

The graft was placed into the recessed bed and sutured using 6.0 polyglactin 910 sutures in an interrupted fashion. The graft was anchored to the anterior lamella using two sutures to secure its position, followed by tying the sutures to the skin using polyglactin 910. Lateral canthopexy and corner sutures were then placed for further stability. A 5.0 silk frost suture was used, and steri strips were applied to the lower lid to maintain eyelid stability and secure the graft.

This study was conducted in accordance with the tenets of the Declaration of Helsinki, and all patients gave informed consent. As the patients received treatment in a private practice setting, institutional review board approval was not obtained for this study.

Following the surgery, patients received postoperative care, which included oral antibiotics and painkillers, along with ophthalmic antibiotic/steroid mixture drops administered four times daily. Frost sutures and steri-strips were removed at 5-7 days post-surgery. The mean follow-up time for patients was 11 months, with a range between 6 to 30 months. During the follow-up period, regular photographs were taken to monitor improvements in scleral show, assess patient satisfaction, and note any postoperative complications.

The main objective of the statistical analysis was to compare the preoperative and postoperative results of MRD2-a (mid-pupil to lower eyelid) and MRD2-b (lateral limbus to lower eyelid) at the longest follow-up time.

Preoperative and postoperative photographs were taken using an Apple iPhone in the examining room with standard lighting conditions. Digital analysis of preoperative and postoperative photos was conducted using Apple MacBook Image Preview software. Corneal diameter (W), center of the pupil to inferior eyelid margin (Y), and the point horizontally aligned with the pupil center at the lateral limbus to inferior lid margin (Z) were measured in pixels. Corneal diameter was considered as 11mm for each patient, and exact measurements were proportionally adjusted to corneal diameter using the following formula: MRD2-a= Yx11/W, MRD2-b= Zx11/W. For instance, MRD2-a was calculated as 127x11/187=7.4mm, and MRD2-b was calculated as 117x11/187=6.8mm (Fig.2).

The statistical analysis was conducted using the NCSS (Number Cruncher Statistical System) 2020 Statistical Software (Utah, USA). Descriptive statistical methods, such as mean, standard deviation, median, frequency, and ratio, were employed to summarize the data. The Shapiro-Wilk test and box plot graphics were used to assess the variables' normal distribution. For normally distributed variables within the population, paired sample t-tests were utilized to compare postoperative intra-group results. For variables that did not follow a normal distribution due to the number of cases, the Kruskal-Wallis test was applied to compare differences between groups. To determine the specific group causing the difference, the Dunn test was employed. Intra-group comparisons for both normally distributed and non-normally distributed parameters were performed using the Wilcoxon signed-rank test.

The significance level was set at p < 0.05 for all statistical evaluations.

A total of 29 eyelids in 21 patients (19 female, 2 male) with a median age of 38.6 years (age range: 20–54 years) underwent lower eyelid retraction surgery using autologous auricular scapha cartilage. The etiology of eyelid retraction was post-blepharoplasty in 13 patients (44.8%), genetic factors in 12 patients (41.4%), and facial palsy in 4 patients (13.8%). Patients with less than 6 months of follow-up were excluded from the study.

No intraoperative complications were encountered, and the procedures were technically successful in all cases. At the first follow-up examination, 29 eyelids of 21 patients showed improvement in terms of retraction. Throughout the follow-up period (ranging from 6 to 30 months), 28 eyelids (96.5%) maintained their improved status. One patient experienced recurrent retraction at 3 months, which was attributed to previous transcutaneous blepharoplasty. Four eyelids required revision due to canthal corner loosening. Three of these patients had undergone more than two previous surgeries, resulting in significantly disrupted canthus-eyelid anatomies. After revisions, eyelid-lateral cantus remained stable during follow-ups. Additionally, one patient with a history of conjunctivachalasis presented with persistent temporal chemosis following surgery. In-office, the fluid was drained, and conjunctiva tightened using thermal cautery, successfully resolving the issue without recurrence.

Functionally and cosmetically, the results were satisfactory in 20 patients (28 eyelids). A statistical analysis was performed to compare the preoperative and postoperative MRD2-a and MRD2-b measurements (Fig. 1). The differences were found to be statistically significant (p = 0.001; p < 0.01). Postoperatively, there was a mean decrease of 1.77 ± 0.80 units in MRD2-a measurements compared to preoperative values (p = 0.001; p < 0.01). Similarly, a mean decrease of 2.04 ± 0.81 units in MRD2-b measurements was observed postoperatively compared to the preoperative measurements (p = 0.001; p < 0.01).

Regarding the indications, the increase in eyelid height values according to MRD2-a were found to be as follows: post-blepharoplasty group: -1,57 ± 0,78, genetic group: -2,02 ± 0,68, facial palsy group: -1,70 ± 1,17. Similarly, the MRD2-b measurements showed the following increases based on indications: post-blepharoplasty group: -1,81 ± 0,94, genetic group:-2,30 ± 0,55, facial palsy group:-2,01 ± 1,02 (Table 1).

Table 1

Assessment of MRD2-a and MRD2-b Scores According to Indications
			Post-blepharoplasty (n = 13)	Genetic (n = 12)	Facial palsy(n = 4)	p
MRD2-a	Preop	Min-Max (Median)	5,9–9,1 (7)	6,5–9,5 (7,6)	5,6–7,5 (6,7)	^b0,128
	Preop	Ave ± Sd	7,18 ± 0,96	7,78 ± 1,00	6,63 ± 0,78
	Postop	Min-Max (Median)	4,3–7,1 (5,6)	4,4–7,5 (6,1)	3,8 − 5,9 (5)	^b0,367
	Postop	Ave ± Sd	5,61 ± 0,87	5,76 ± 1,02	4,94 ± 1,08
		p	^c0,002**	^c0,002**	^c0,068
Difference (preop-postop)		Min-Max (Median)	-0,1–3,2 (1,7)	1,2–3,4 (1,9)	0,7 − 3,3 (1,4)	^b0,366
Difference (preop-postop)		Ave ± Sd	-1,57 ± 0,78	-2,02 ± 0,68	-1,70 ± 1,17
MRD2-b	Preop	Min-Max (Median)	5,4–9,2 (6,6)	6,8–8,9 (7,7)	4,9 − 7,3 (6,8)	^b0,036*
	Preop	Ave ± Sd	7,04 ± 1,18	7,75 ± 0,63	6,46 ± 1,04
	Postop	Min-Max (Median)	3–7,1 (5)	4,3–7,5 (5,5)	3,4–5,6 (4,4)	^b0,371
	Postop	Ave ± Sd	5,23 ± 1,11	5,45 ± 0,95	4,45 ± 1,05
		p	^c0,001**	^c0,002**	^c0,068
Difference (preop-postop)		Min-Max(Median)	0,1–3,8 (1,6)	1,4 − 3,1 (2,3)	1,2–3,5 (1,7)	^b0,179
Difference (preop-postop)		Avet ± Sd	-1,81 ± 0,94	-2,30 ± 0,55	-2,01 ± 1,02
^bKruskall Wallis Test ^cWilcoxon Signed Rank Test
p < 0,05 *p < 0,01

Lower eyelid retraction is a complex condition that can arise due to various etiologies, and its correction poses significant challenges. Surgical intervention is typically indicated when patients experience lagophthalmos, exposure keratopathy, and cosmetic concerns [5]. Several surgical techniques are commonly employed to address lower eyelid retraction, including midface lifting, canthoplasty to address horizontal laxity, release of lower eyelid retractors, and elevation of the lower lids using spacer grafts [6–9]. Spacer grafting becomes particularly crucial when there is scarring and shortening of the middle and posterior lamella [10–12].

Spacer grafts can be classified into three main categories: autologous, allogenic, and alloplastic [13]. Over time, various spacer graft materials have been utilized in these procedures. Autologous grafts are widely employed and encompass materials such as hard palate, tarso-conjunctiva, dermis fat, and auricular cartilage [14]. Allogenic spacer options consist of banked sclera and acellular human dermis. Additionally, synthetic materials, including polytetrafluoroethylene, mersilene, and porous polyethylene, have also been made available for this purpose. All spacers used in lower eyelid retraction surgery have their advantages and disadvantages, and there are numerous studies comparing different graft materials.

The hard palate mucosal graft is a widely used autologous spacer material in lower eyelid retraction surgery due to its advantages, which include flexibility, appropriate tensile strength, and excellent support. However, the main drawbacks associated with this graft are donor site complications and oral discomfort [4, 15, 16, 17].

In their study, Patel et al. investigated 17 patients with postblepharoplasty eyelid retraction who underwent hard palate graft placement and lateral tightening [7]. The results showed a mean improvement in scleral show of at least 1.8 mm after the surgical procedure. The follow-up period lasted for 14 months, and the authors reported excellent outcomes in all cases. Nevertheless, the study reported that there were two cases of complications among the patients, including one incident of secondary bleeding from the donor site and one case of corneal abrasion.

Wearne et al. presented the outcomes of lower eyelid retraction surgery using hard palate grafting in a study involving 62 patients and 102 eyelids [18]. The surgical indications for the procedure were thyroid eye disease, idiopathic retraction, and isolated previous squint surgery. Satisfactory lid position was achieved in 87 out of 102 (85%) eyelids. However, the most common complication observed during the postoperative period was donor site bleeding, with an incidence rate of 10%. This complication is considered one of the main disadvantages associated with the use of hard palate mucosal grafts.

In the study conducted by Oestreicher et al., repair was performed using hard palate mucosa, free tarsoconjunctival, and free scleral grafts in 659 eyelids of 400 patients with lower eyelid retraction caused by thyroid ophthalmopathy, previous surgery, trauma, and idiopathic reasons. The researchers did not find a significant difference in the success of eyelid elevation among the different graft types [4]. The most commonly encountered complications were donor site bleeding, with rates of 10% in the tarsoconjunctival group and 7.8% in the hard palate group, showing similar occurrences. However, wound dehiscence was significantly more prevalent in the tarsoconjunctival group compared to other groups.

In their study, Baylis et al. evaluated the outcomes of lower eyelid retraction repair using posterior auricular cartilage in patients with dystroid, socket, and postblepharoplasty conditions. The surgical procedure was successful without any complications in 80 out of 83 eyelids. The authors concluded that this spacer material proved to be superior as it exhibited minimal shrinkage and offered the advantage of being autologous [19].

This retrospective study aimed to analyze the outcomes of using autologous scapha cartilage for the improvement of lower eyelid retraction in patients affected by postblepharoplasty, facial palsy, and genetic variants. The technique utilized in this study represents a modification of previously reported methods, incorporating the use of auricular scapha cartilage. While scaphal cartilage harvesting in oculoplasty was initially described by Baylis et al., the incision in their technique was made from the posterior surface of the ear.⁵ In a broader series discussing the repair of lower eyelid retraction using posterior auricular cartilage, Baylis et al. again published successful outcomes, reporting that 80 out of 83 eyelids were effectively treated [19].

In their study, Liao et al. described the elevation of the lower eyelid in anophthalmic patients with lower eyelid retraction and shallow fornices using auricular scapha cartilage. They reported successful outcomes in 86% of the 29 patients included in the study. The use of auricular scapha cartilage proved to be effective in achieving satisfactory results in elevating the lower eyelid in these anophthalmic patients with lower eyelid retraction [14].

Allografts and xenografts offer certain advantages, including less time-consuming surgeries and the absence of any donor site, which have contributed to their increasing popularity. Various acellular dermal matrices derived from human, bovine, or porcine tissues are available as options [20–22]. However, it is worth noting that these products may not be readily accessible in some countries, and their use can also contribute to an increase in the overall cost of the surgery. This tissue poses some concerns, such as the risk of contamination, which makes autologous materials a logical and preferable choice [17].

In a study conducted by Barmettler et al., they compared the results of using autologous auricular cartilage, bovine acellular dermal matrix, and porcine acellular dermal matrix for eyelid elevation. The study concluded that there was no significant difference in eyelid elevation among the three groups [2]. The cartilage graft used in this study was obtained from behind the ear, which is different from the cartilage graft used in our study.

In our study, we utilized auricular scaphal cartilage obtained through a preliminary approach in all patients. The cases requiring reoperation were not primarily due to issues with the spacer graft but rather resulted from canthal loosening, which was associated with multiple previous canthal surgeries the patients had undergone.

Our observations indicated that this graft material proves highly practical and effective as a spacer in eyelid retraction. Additionally, we observed no shrinkage in the graft, and its acquisition through the preliminary approach may potentially reduce postoperative complications, such as bleeding. Moreover, we found the harvesting process to be straightforward and incurs no additional cost and is of autologous origin, adding to its favorable characteristics.

These findings highlight the promising attributes of auricular scaphal cartilage as a spacer in eyelid elevation procedures, which may lead to enhanced surgical outcomes and greater patient satisfaction.

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No competing interests reported.

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Lower Eyelid Retraction Repair Using Autologous Auricular Scapha Cartilage

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