Acute Macular Edema Associated With an Infected Scleral Buckle

Exposure or infection of a scleral buckle is an unusual complication of retinal detachment surgery. It has been reported in 0.5% to 18.0% of all procedures.¹ Patients may be seen with ocular irritation, pain, discharge, redness, and sometimes visual loss. Reported causes of visual loss include uveitis with vitreous clouding, recurrent retinal detachment secondary to proliferative vitreoretinopathy, and macular distortion.^1-4 This case report describes angiographically documented diffuse macular edema associated with acute visual loss in a patient with an infected and extruded scleral buckle.

A 77-year-old white man was referred to our clinic with a 2-week history of new-onset visual blurring in the left eye. The patient had an ocular history notable for severe myopia and retinal detachments in both eyes. The patient's medical history was noteworthy only for controlled hypertension. He underwent scleral buckling procedures with silicone explants in the late 1960s. He had cataract extractions in 1984 (left eye) and 1991 (right eye), resulting in bilateral aphakia. In 1993, the patient first was seen by his ophthalmologist with redness, discharge, and ocular irritation in the left eye. At that time, he had an exposed area of conjunctiva superiorly over his scleral buckle. The buckle was still thought to be well positioned, and the patient was treated using topical ciprofloxacin. He was seen periodically and was thought to be doing well with vision of 20/25 OS with conservative management. In August 1996, the patient had acute painless visual loss to 20/60 OS. Examination revealed an exposed scleral buckle superiorly with purulent discharge (Figure 1). Funduscopic examination revealed diffuse macular and retinal edema. There was no intraocular inflammation. A fluorescein angiogram was obtained, revealing diffuse macular hyperfluorescence consistent with the macular edema noted clinically (Figure 2). There was no evidence of vasculitis. The patient was given oral cefazolin, 250 mg 4 times daily, for 4 days and topical ciprofloxacin drops 4 times daily and subsequently underwent surgical removal of the scleral buckle through the superior conjunctival opening. An encircling band and tire were removed. Cultures of these elements were negative for organisms. Marked scleral thinning was noted beneath the scleral buckle site at the time of surgery (Figure 3). The conjunctiva was closed over this area. Subconjunctival vancomycin, 50 mg, was injected at the end of surgery. The patient was given polymixin-trimethoprim drops 4 times daily and continued to use oral cefazolin for a total of 7 days. Two weeks after surgery,^1,4 the vision had improved to 20/25 OS. Funduscopic examination revealed no appreciable residual macular thickening. Further follow-up at 10 months revealed no changes, with vision remaining at 20/25 OS.

This case demonstrates diffuse macular edema associated with an infected scleral buckle resulting in acute visual loss. Prompt removal of the infected scleral buckle may result in rapid visual recovery, as noted in our patient. The macular edema is likely the result of the infection and associated scleritis. This inflammatory process can extend from the sclera and result in several ocular complications, including uveitis.⁵ Although no intraocular inflammation was seen during our examination, it is also possible that prior inflammation existed and led to the development of macular edema. In addition to macular edema, long-standing uveitis may also cause cataracts and glaucoma that can also result in visual loss.⁵

Our patient's infection occurred nearly 30 years after the procedure. Most infections occur much earlier, with a mean of 2 months in one series and 8 months after initial surgery in another series.^1,4 Our patient had a dramatic return of visual acuity with normalization of the fluorescein angiogram (Figure 4). Visual acuity results after removal of an infected scleral buckle are rarely reported in the literature. Retinal detachment is the most common cause of poor vision after removal of scleral buckles.^1,3 Late redetachment rates range from 45% to 39%, with the highest percentage occurring when the buckle has been in place for less than 6 months.^1,2,6 Most detachments occur within the first 6 months after removal.⁶ In our patient, the retina has remained attached at 10 months after surgery. Scleral thinning, as seen in our patient, has been reported after infection and removal of scleral buckles as well. One series⁴ showed that this occurred in nearly 30% of the cases.

Macular edema may be difficult to detect in these patients with infected or extruded scleral buckles because discharge may affect corneal clarity and the patient may be photosensitive. The use of fluorescein angiography may be a useful adjunct to making the diagnosis. Recognition of macular edema may encourage earlier removal of the buckle so as to avoid complications of chronic macular edema.

Supported in part by an unrestricted grant from Research to Prevent Blindness Inc, New York, NY, and by core grant EY01931 from the National Institutes of Health, Bethesda, Md. Dr Dev is a Heed Ophthalmic Foundation (Cleveland, Ohio) Fellow.

Reprints: William F. Mieler, MD, Medical College of Wisconsin Eye Institute, 925 N 87th St, Milwaukee, WI 53226-4812 (e-mail: wfmieler@mcw.edu).