Scleral patch graft with mucous membrane overlay for scleral perforation

Introduction

Surgical management of scleral thinning using scleral patch grafts, fascia lata, multilayered amniotic membrane graft (AMG), and synthetic Gore-tex has been attempted successfully.[1] The sclera, being an avascular structure without epithelium it, requires an overlay of vascularization to prevent its necrosis and melting. Conventionally, this overlay has been in the form of a conjunctival flap or an AMG.[2] However, in cases of scleral perforation, AMG fails to provide adequate reinforcement; hence, a mucous membrane graft (MMG) could be a better option.

Case Report

A 60-year-old female presented with complaints of pain, discharge, and a decrease in vision in her left eye for 1 week duration. She had undergone cataract surgery in that eye 3 weeks back elsewhere. This patient was being treated as a case of scleritis and started on topical and oral steroids. Following this, her symptoms worsened, and she was referred to a higher center. On examination, the left eye had a visual acuity of hand movements with a good projection of rays. Slit-lamp examination showed diffuse conjunctival congestion, and inferior conjunctival necrosis from 5 to 8 O’clock hours with a large area of sclera melt extending up to the fornix and overlying thick discharge. The cornea had descemet’s membrane (DM) folds with diffuse pigments on the endothelium. The anterior chamber (AC) showed cells 4+, flare 4+ with fibrin membrane over the pupil and posterior chamber intraocular lens. B-scan showed mild vitritis with an attached retina. Considering a provisional diagnosis of infective scleritis, scrapping was done for gram stain, KOH mount, and culture sensitivity. Gram stain revealed numerous pus cells and few Gram-negative bacilli. The patient was then started on 5% topical amikacin, 1% atropine, and oral levofloxacin. Forty-eight hours later, there was progressive scleral thinning and perforation measuring 3 mm × 3 mm with vitreous prolapse [Figure 1]. The cornea had diffuse DM folds with occlusio pupillae. B-scan showed choroidal detachment. The patient was advised of a left eye scleral patch graft with an overlay of MMG to maintain structural integrity under a very guarded visual prognosis.

Figure 1.

Scleral thinning with perforation measuring 3 mm × 3 mm and vitreous prolapse seen 48 h after presentation

Surgery

Under peribulbar anesthesia, the necrotic conjunctiva surrounding the infected sclera was excised, followed by undermining of the healthy conjunctiva all around. The prolapsed vitreous was cut, and the necrotic sclera around the perforation was excised. A donor scleral patch graft measuring 10 mm × 8 mm was trimmed to fit the area of sclera thinning and sutured to the scleral bed using 9-0 nylon sutures [Figure 2]. The lower lip and inner mucosa were then cleaned with 2% povidone-iodine and a MMG measuring around 15 mm × 10 mm was harvested from the lower lip under local anesthesia. The harvested MMG was further trimmed, secured over the sclera patch with fibrin glue, and reinforced with 8-0 vicryl sutures [Figure 3]. On the first postoperative day, the MMG was healthy with intact sutures. The postoperative regimen included 5% amikacin eye drops six times a day, polymyxin-dexamethasone eye drops three times a day, 1% atropine two times a day, betadine mouthwash, and oral ornidazole with ofloxacin. On the 10^th day follow-up, the MMG had a good uptake over the sclera. Five percent amikacin was tapered to three times a day, polymyxin-dexamethasone eye drops were switched to loteprednol–gatifloxacin eye drops four times a day, and cycloplegic was continued. One month after surgery, there was uptake of MMG over the sclera in the periphery. The cornea showed DM folds with an iris bombe, iridocorneal touch, and occlusio pupillae. Hence, a sectoral iridectomy with synechiolysis was done. At 4 months, her best-corrected visual acuity (BCVA) was 6/18 and there was vascularization over the scleral graft periphery with small central bare sclera. The cornea was clear with a quiet AC [Figure 4]. Intraocular pressure (IOP) was 15 mmHg. Loteprednol - gatifloxacin eye drops were tapered over 3 months. Six months postoperatively, there was complete vascularization over the scleral graft with a clear cornea and AC [Figure 5]. BCVA was maintained on 6/18 with an IOP of 14 mmHg at 1-year postoperative.

Figure 2.

Intraoperative photo after placement of scleral graft

Figure 3.

Intraoperative photo after placement of mucous membrane graft overlay

Figure 4.

At 4 months postoperative period, there was peripheral vascularization over the scleral graft with a small central bare sclera

Figure 5.

At 6 months postoperative period, there was complete vascularization over the scleral graft with a clear cornea and a quiet anterior chamber

Discussion

Oral mucosal grafts have been used in the treatment of contracted sockets, fornix reconstruction in Steven–Johnsons syndrome, ocular cicatricial pemphigoid, and also in keratoprosthesis-related corneal melts.[3] In the management of scleral perforation, MMG as overlay is a better option as it provides superior structural support compared to AMG.[4] In addition, oral mucosa is highly resistant to microbial agents and inflammation due to its inherent biological properties.[3,4]

Lamarca-Mateu et al. reported a case of severe necrotizing scleritis surgically managed with a scleral patch graft and AMG overlay. However, on follow-up, there was necrosis of the graft, so a resection of the necrosed scleral graft with buccal mucosa overlay was done. This provided good results with no melt or recurrence.[5] Wang et al. reported a case series of three patients where a combination of tenonplasty with a free oral buccal mucosa autograft was done for sclerocorneal melts secondary to chemical burns. At 6 months follow-up, the area of the sclerocorneal melt healed well, thereby salvaging the globe integrity.[6]

In our case, there was a large area of conjunctival necrosis for 3 O’clock hours with extension up to the fornix and loss of structural integrity owing to scleral perforation with vitreous prolapse. A scleral patch graft was preferred due to its stiff structure, ready availability from whole donor eyes and the natural curvature of the sclera, which allows a better fit to the host defects. MMG was chosen as an overlay for better reinforcement over the sclera.[7] In addition, MMG is easy to harvest and accessible, and the donor mucosal bed heals without scarring. On follow-up of our patient, there was good vascularization over the scleral graft with no symblepharon formation. This emphasizes the fact that scleral graft with mucous membrane overlay provides a good outcome in scleral perforation. Once structural integrity was obtained, visual rehabilitation in the form of sectoral iridectomy and synechiolysis was done.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conclusion

Scleral patch graft with MMG overlay could be considered the primary surgical option in scleral perforation, especially in cases with vitreous prolapse and loss of globe integrity.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.