Amniotic Membrane Transplantation for Paracentral Corneal Perforations

Case Report

J Ophthalmol & Vis Sci. 2023; 8(1): 1074.

Amniotic Membrane Transplantation for Paracentral Corneal Perforations

Guo P1#, Su JJ1#, Lin BT1, Zhang Y2* and Zhu YT2*

¹Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen 518040, China

²BioTissue (TissueTech, Inc.), 7235 Corporate Center, USA

*Corresponding author: Yuan Zhang & Yingting Zhu Tissue Tech, Inc., 7235 Corporate Center Drive, Suite B, Miami, FL 33126, USA

Received: December 29, 2022; Accepted: February 08, 2023; Published: February 15, 2023

Abstract

Objective: To report the clinical efficacy of Amniotic Membrane Transplantation (AMT) for paracentral perforations caused by Blepharokeratoconjunctivitis (BKC).

Methods: A retrospective review was performed on consecutive patients that had paracentral corneal perforations caused by BKC and were subsequently treated with AMT between October 2019 and September 2021. Visual acuity (BCVA), anterior chamber depth, angle opening, corneal thickness and number of Demodex mites were examined before and after the operation.

Results: Eleven eyes of 11 patients (2 males, 9 females, aged 11- 22 years old) with BKC were included in the analysis. Three months after AMT, BCVA significantly improved from 1.14 ± 0.8 at baseline to 0.35 ± 0.2 (p=0.004) and the proportion of patients with mite infestation decreased from 7 cases (64%) to 2 cases (18%). OCT confirmed the corneal perforations healed with normal corneal thickness and formation of anterior chamber with normal angle opening. During the follow up duration of 6-17 months, no recurrence or complications were noted.

Conclusion: This case series suggests AMT can restore vision and corneal thickness in patients with aseptic corneal perforations caused by BKC.

Keyword: Blepharrokeratoconjunctivitis; Corneal perforation; Amniotic membrane; Transplantation

Introduction

Blepharrokeratoconjunctivitis (BKC) is a type of chronic, inflammatory eyelid disease involving the conjunctival and corneal [1-4]. The early symptoms include photophobia tears, red eyes, blepharospasm and scaly deposition on margin with a history of recurrent chalazion. BKC can cause progressive conjunctivitis, keratitis and various corneal complications such as: corneal infiltration, corneal neovascularization, scarring and corneal ulcers [3,5]. Due to the lack of self-protection and the poor awareness of the diagnosis, the situation is more severe among young people than adults. BKC is often under diagnosed or misdiagnosed in clinical practice, which can often lead to corneal perforations and significant visual impairment in these patients.

Corneal perforations are an ophthalmic emergency regardless of the etiology. A few patients can be cured by timely intervention of keratoplasty. However, most patients lose their vision permanently due to formation of adhesive leukoplakia or enucleation due to treatment delay. For corneal perforations in younger patients, early and effective treatment is particularly important to preserve the eyeball and save vision. Amniotic membrane transplantation has been widely used in the treatment of various ocular surface diseases in recent years, such as ocular surface chemical injuries [6], corneal epithelial and nerve regeneration [7], wound healing by limbal stem cells [8], corneal perforations [9], corneal ulcers [10-12] and dry eyes [13]. This study retrospectively reviewed 11 cases of patients with paracorneal central perforations caused by BKC treated by amniotic membrane transplantation in our hospital from October 2019 to September 2021.

Materials and Methods

A retrospective review was performed on 11 eyes of 11 consecutive patients that had paracentral corneal perforations caused by BKC and were subsequently treated with AMT between October 2019 and September 2021. This study followed the tenets of the Helsinki Declaration on ethical principles for medical research involving human subjects and was approved by the Committee of Eye Research Institute Review Board, Shenzhen Eye Hospital, China. These patients failed to improve after bandaging for 2-5 days and subsequently underwent amniotic membrane packing and amniotic membrane transplantation treatment. Best Corrected Visual Acuity (BCVA) and number of eyelid mites were compared before and after operation. The changes of anterior chamber depth, angle opening and corneal thickness in the perforated area were also assessed using slit light and anterior segment OCT.

The BKC diagnostic criteria were as follows: (a) presence of blepharitis: 1. neovascularization and congestion of palpebral margin; 2. lash root scaly, cuff-like suede, eyelash loss or disorder; 3. eyelid margin scab or ulcer; 4. the lipid plug or blocking at the opening of the meibomian gland and the quality of the meibum changed. 5. eyelid edge is thickening and not smooth. Diagnosis was confirmed if they had presence of the first item along with any one item of 2 to 5 items. (b) History of recurrent conjunctivitis and keratopathy with blepharitis; (c) and had one of the following typical signs: 1. conjunctival hyperemia, papillary hyperplasia, follicular formation and vesicular conjunctivitis; 2. punctate keratitis, punctate erosion around the cornea, infiltration, ulcer formation or even perforations, or shallow neovascularization, formed with varying degrees of corneal opacity. (d) After the treatment of blepharitis was improved, the keratoconjunctival lesions were obviously improved, and the corneal neovascularization could quickly subside. Bacterial and fungal culture were performed routinely on the ulcerated edge of corneal perforations by scraping before surgical operation.

Detection of Mites [14,15]

Eyelid mites were assessed by optical microscope (Olympus) before surgery and after 3 months. Three eyelashes were taken from the upper and lower eyes of the patient (eyelashes with lipid-like cuff secretions or trichiasis with lipid-like cuff secretions were obtained from the inner, middle and outer edges of the eyelid), hence 12 lashes were taken from both eyes. The eyelashes were placed on a slide in parallel with cedar drops under a covered glass. The number and morphology of demodex mites were then counted. Positive presence of mites was defined as having a Demodex count of 3/3 eyelashes in any of the 4 eyelids. Less than the above criteria were suspected positive, combined with clinical manifestations, if necessary, reviewed and confirmed.

Amniotic Membrane Transplantation

Preparation of the amniotic materials [16,17]: The amniotic membrane was derived from placental tissue of healthy cesarean section women without vaginal infection. Conventional serological tests for syphilis antibody, human immunodeficiency virus antibody, Hepatitis B surface antigen and Hepatitis C antibody were all negative. Follow the references from Dr. Scheffer Tseng to prepare and preserve amniotic membrane: the amniotic membrane was separated from the choroid after cleaning the placental blood clot and cut into 3cm×4cm grafts. The treated amniotic membrane was stored in a sterile vial of glycerol and DMEM medium (V/V=1:1) at -80°C. The amniotic membrane was taken out before operation, and the amniotic membrane was immersed in 1:2000 tobramycin physiological saline on an aseptic table and rehydrated for 20 minutes for clinical use.

Surgical methods: After routine disinfection, 0.5% Proparacaine Hydrochloride Eye Drops (Alcon) was administered every 5 minutes and 3-4 times for topical anesthesia to begin operation. After eyelid opening, 5% povidone iodine solution was used to flush the conjunctival sac (avoiding corneal perforations). After that, the rehydrated amniotic membrane was folded in 2-4 layers, packed into the corneal perforation defect, and sutured with 10-0 nylon thread (10-0 Nylon 698001, Alcon) on the adjacent relatively normal corneal tissue with 2-3 stitches. Another layer of fresh amniotic tissue was covered on the amniotic membrane surface at the tamping site, with a range slightly larger than 1-2mm in the lesion area. The second layer of amniotic membrane was sutured and fixed on the normal corneal tissue around the perforation margin with 10-0 nylon thread. After the operation, a therapeutic bandage lens and TobraDex dexamethasone eye ointment (TobraDex, Alcon) was applied, the bandage was pressurized, and opened for examination 24 hours later.

Postoperative treatment: After 24 hours of eye bandaging, the eye was opened locally. TobraDex Eye Drop (Alcon) was administered 4 times a day, and 0.5% Levofloxacin Eye Drops (Santen) was given 4 times a day, and TobraDex Ointment (Alcon) was applied once a night for 2 weeks. After that, 0.02% Fluorometholone Eye Drops (Santen) was used 4 times a day, Pranoprofen Eye Drops (Senju Pharmaceutical Co, Ltd.) was applied 4 times a day for 2 weeks, 0.02% Fluorometholone Eye Drops (Santen) was applied 3 times a day, and 0.3% Sodium Hyaluronate Eye Drops (Santen) 4 times a day, for 1 to 2 months.

Postoperative follow-up: After one week, two weeks, one month, three months and six months, visual acuity testing, slit lamp examination and Anterior segment OCT (Moptim, OSE- 1200) were performed to observe the visual function, depth of anterior chamber, healing of corneal perforations and changes in corneal thickness. The therapeutic bandage lens was removed 2 weeks after surgery, and the surface of the corneal suture was removed from the cornea. The deep corneal suture lines were removed 1 to 2 weeks later.

Statistical methods: SPSS 25.0 software was used for statistical analysis. ANOVA and T test were used to verify the results of preoperative and postoperative BCVA. BCVA was converted to the LogMAR for statistical analysis.

Results

A total of 11 eyes of 11 consecutive patients were included in the analysis including 2 males (2 eyes, 18%), 9 females (9 eyes, 82%), aged 11 to 22 years old, with BKC onset between 14 months and 8 years. All patients presented with paracentral corneal perforations between 0.5 – 1mm that affected the surrounding 2-3mm corneal area. All affected areas were negative for microbial growth. All patients underwent AMT without complication within one week of hospital admission.

At 3 months after AMT, BCVA significantly improved from 1.14 ± 0.8 at baseline to 0.35 ±0.2 (p=0.004) (Table 1).

The anterior chamber was also formed and the tissue in the corneal perforation area healed with normal corneal thickness as determined by OCT. The proportion of patients with Demodex mites decreased from 7 out of 11 patients at baseline to 2 out of 11 patients at 3 months. Throughout the follow up duration of 6-17 months, the eyelid inflammation was stable with no recurrence of keratopathy, no secondary infection, and no other complication (Table 2, Figure 1 and Figure 2).