Unusual Case of Acute Corneal Hydrops in Mooren's Ulcer Treated with Intracameral Injection of Perfluoropropane.

A 15-year-old boy was diagnosed with Mooren's ulcer in the right eye at our cornea clinic. On treatment, he developed acute corneal hydrops, and the vision in the right eye dropped to perception of light. The patient was treated with intracameral injection of perfluoropropane (C3F8) gas which resulted in complete resolution of corneal edema. Contact lens fitting yielded a good visual outcome with a best-corrected visual acuity of 20/80. To the best of our knowledge, this is the only case reporting the occurrence of acute corneal hydrops in a child with Mooren's ulcer.

Introduction

Mooren's ulcer is an idiopathic, painful, progressive peripheral ulcerative keratitis.[1] Its occurrence in children is extremely rare.[2] We report a case of Mooren's ulcer in a child developing acute corneal hydrops during the course of treatment, which resolved on injecting intracameral C3F8 with good visual outcome. We report this case because of its unusual presentation as well as the favorable visual outcome with treatment.

Case Report

A 15-year-old boy presented to our hospital with 1 month history of severe pain, redness, photophobia, and diminution of vision in the right eye. Past ocular and medical history and systemic examination were unremarkable. On ocular examination, his best-corrected visual acuity (BCVA) in the right eye was perception of light and in left eye was 20/20. Intraocular pressure (IOP) was normal in the left eye and could not be measured in the right eye. Slit-lamp examination of the right eye showed peripheral corneal ulceration extending from 2 o'clock to 10 o'clock position with cellular infiltration and a central overhanging edge. Iris incarceration with pseudocornea formation was noted inferiorly in an area of 2 o'clock hours. There was no associated scleritis or anterior chamber inflammation. Fundus was not visible in the right eye. Corneal scraping of the ulcer did not show any organisms on either smears or routine cultures. Anterior and posterior segment examination of the left eye was normal. Anterior segment photograph was not possible at that moment due to the presence of severe photophobia.

He was diagnosed with Mooren's ulcer in the right eye based on the clinical features and the absence of systemic disease confirmed by relevant systemic investigations such as normal blood count, normal erythrocyte sedimentation rate, and negative markers of autoimmune disorders. Conjunctival resection along with tissue adhesive and bandage contact lens (BCL) placement was performed. He was treated with systemic as well as hourly topical steroids.

On serial follow-up, there were peripheral vascularization and scarring, and he was shifted to oral methotrexate 7.5 mg weekly, and systemic and topical steroids were tapered. BCVA in the right eye improved to finger counting at 3 m.

One month later, he presented with acute onset further diminution in vision in the right eye. The BCVA dropped to perception of light. On slit-lamp examination, there was mild conjunctival congestion with marked corneal edema (central 5 mm) and peripheral cornea scarring as previously. A diagnosis of acute corneal hydrops (Grade 2) in a resolving Mooren's ulcer was made [Figure 1]. Intracameral injection of 0.1 ml of nonexpansile C3F8 (14%) was done through a 30-gauze needle under topical anesthesia. Anterior chamber was left with two-third chamber of gas. On postoperative examination, the central corneal edema started resolving 1st week onward. The IOP was measured with a noncontact tonometer on the 1st postoperative day and with applanation tonometer on subsequent visits. IOP was recorded <18 mmHg at all visits. Two months later, the edema completely resolved and there was central corneal scarring of macular grade [Figure 2]. He was fitted with Rose-K IC (Irregular Cornea) contact lens in the right eye with a BCVA of 20/80. A corneal topography (Keratograph C; Oculus Optikgerate GmbH, Wetzlar, Germany) of the left eye was done which showed no evidence of any corneal ectatic disorder [Figure 3].

Figure 1

Acute corneal hydrops in Mooren's ulcer (right eye)

Figure 2

Two months postinjection with resolved corneal edema (right eye)

Figure 3

Corneal topography of the left eye

Discussion

Mooren's ulcer is a rare, chronic, relentlessly progressive peripheral ulcerative keratitis without scleral involvement or underlying systemic disease.[1] In various studies, Mooren's ulcer has been shown to occur more frequently in middle-aged and elderly individuals. This is possibly due to the phenomenon of immunosenescence which results from increasing abnormalities in the immune system of aging population.[3] Occurrence of Mooren's ulcer in children is extremely rare. Mathur et al. have described the epidemiology, clinical features, management, and outcomes of Mooren's ulcer in children <18 years of age.[2] They reported 14 eyes of 11 children over a period of 24 years.

Therapeutic strategy depends on the activity and severity of disease. Main line of treatment includes conjunctival resection, application of tissue adhesive and BCL, topical and systemic steroids, systemic immunosuppressants, and keratoplasty.[4] Systemic steroids are required for aggressive bilateral and unilateral cases. However, the prolonged use of systemic corticosteroids in pediatric patients can be associated with serious side effects. Hence, oral methotrexate is preferred as a steroid sparing agent.[2] Since our patient had an aggressive unilateral ulcer, he was given a short course of high-dose oral corticosteroid followed by methotrexate.

Acute corneal hydrops is the development of marked corneal edema due to a tear in Descemet's membrane followed by leakage of aqueous into the stroma.[5] It has frequently been reported in keratoconus and other corneal ectatic disorders and even following refractive surgery and keratoplasty.[56] To the best of our knowledge, no case of hydrops developing in Mooren's ulcer has been reported. One of the causes could be a trivial trauma. However, the cause for the Descemet's break in our case could not be elicited. Acute corneal hydrops can be diagnosed based on slit-lamp findings. Investigations such as anterior segment optical coherence tomography (ASOCT) are required to document the size and extent of edema and Descemet's membrane tear.[6] Unfortunately, our hospital did not have the facility of ASOCT when the patient presented to us.

The management of hydrops can be conservative or surgical. The various surgical interventions described are intracameral injection of air/gas, compressive sutures with gas injection, amniotic membrane transplantation with cauterization, cyanoacrylate tissue adhesive with BCL, and penetrating keratoplasty.[56] Hydrops in keratoconus and pellucid marginal corneal degeneration has been previously treated with intracameral C3F8 gas. Basu et al. demonstrated that intracameral injection of C3F8 significantly reduces the duration of corneal edema in keratoconus as opposed to conservative management. However, the final visual acuity achieved was not different in the two groups.[7] C3F8 acts like a tamponading agent, thus preventing further aqueous penetration into the corneal stroma facilitating faster wound healing of the corneal endothelial cells by bringing closer the ruptured edges of the torn Descemet's membrane. Due to the rare nature of the disease, in cannot be said conclusively that the treatment shortened the duration of edema in our case, but timely intervention definitely led to a good visual outcome. This case report is thus unique in reporting the occurrence of acute corneal hydrops in Mooren's ulcer in a pediatric patient and its successful management.

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