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BACKGROUND/AIMS: Vitamin A deficiency, often presenting with nyctalopia, has been described in a number of patients with malabsorption as a result of intestinal bypass surgery and, more recently, bariatric surgery. In these reports vitamin A deficiency developed within several years of gastric or intestinal surgery. Three patients who developed decreased vision from vitamin A deficiency more than 18 years after their intestinal surgery are reported. METHODS: A retrospective review of the clinical findings of all patients diagnosed with vitamin A deficiency, as confirmed by serological testing, over the past year in a single neuro-ophthalmic practice. RESULTS: Four patients with vitamin A deficiency were seen, three of whom had intestinal surgery more than 18 years before the development of visual symptoms. CONCLUSION: The authors suggest that vitamin A deficiency should be suspected in patients with unexplained decreased vision and a history of intestinal surgery, regardless of the timing of the surgical procedure.

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AIM: To determine the clinical features of amiodarone induced optic neuropathy, which may help distinguish it from non-arteritic anterior ischaemic optic neuropathy. METHODS: Retrospective observational case series of patients diagnosed with amiodarone induced optic neuropathy at the neuro-ophthalmology service from March 1998 to February 2001. Amiodarone was discontinued after discussion with the patient's cardiologist. Visual acuity, colour vision, automated perimetry, and funduscopy were performed on initial and follow up examinations. RESULTS: Three patients with amiodarone induced optic neuropathy presented with mildly decreased vision, visual field defects, and bilateral optic disc swelling. Upon discontinuing the medication, visual function and optic disc swelling slowly improved in all three patients. CONCLUSION: Amiodarone induced optic neuropathy can present with visual dysfunction, and is typically a bilateral process. Upon discontinuation of amiodarone, slow resolution of optic disc swelling occurs and visual function improves in some patients.

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OBJECTIVE: To determine the anatomic outcomes of eyes treated with laser photocoagulation for threshold retinopathy of prematurity and to identify potential risk factors for unfavorable outcomes after treatment. DESIGN: Retrospective, noncomparative case series. INTERVENTION: Photocoagulation of the peripheral avascular retina with an argon or diode laser indirect ophthalmoscope. PARTICIPANTS: One hundred twenty eyes of 81 infants with threshold retinopathy of prematurity treated with laser photocoagulation from 1989 through 1997 with at least 12 months of follow-up after treatment. MAIN OUTCOME MEASURES: The principal outcome was the presence of an unfavorable anatomic outcome defined as a retinal detachment, macular fold, or retrolental tissue. RESULTS: One hundred nine of 120 eyes (91%) had favorable outcomes. Eleven eyes (9%) had retinal detachments, and 1 of the 11 also had retrolental tissue. Zone 1 eyes appeared to be 3.3 times more likely to have an unfavorable outcome compared with zone 2 eyes, but the 95% confidence interval (0.8-14.5) did not support this statistically. Twenty-four of 109 eyes (22%) experienced dragging of the temporal vessels. Those with zone 1 disease were 13.7 times more likely to experience temporal dragging compared with zone 2 eyes (95% confidence interval, 3.3-57.2). CONCLUSIONS: After laser photocoagulation for threshold retinopathy of prematurity, 91% of eyes had a favorable anatomic outcome. Compared with zone 2 eyes, zone 1 eyes may be more likely to have temporal dragging of the retinal vessels. Laser therapy is effective in the treatment of threshold retinopathy of prematurity.

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PURPOSE: To describe a case of fungal keratitis in a soft contact lens wearer. METHODS AND RESULTS: A 57 year old female, compliant, frequent replacement soft contact lens wearer, with a possible prior history of herpes simplex keratitis, presented with pain and injection of her left eye of four weeks duration. Gram stain of a corneal ulcer of the left eye revealed fungal organisms and cultures grew Fusarium solani. The infiltrate responded to topical and systemic antifungal agents, but a corneal perforation developed which required a therapeutic penetrating keratoplasty. CONCLUSIONS: Fungal infections are a cause of corneal ulcers in contact lens wearers. Despite the use of topical and systemic antifungal agents, fungal ulcers frequently require surgical intervention.

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PURPOSE: To report a 6-week-old male with extreme proptosis caused by thrombosed orbital varices. METHODS: A 6-week-old male presented with advanced proptosis of his left eye. Computed tomography and magnetic resonance imaging studies of the orbits revealed a heterogeneous cystic mass that filled the entire left orbit. Extreme proptosis and corneal exposure prompted urgent surgical excision of the mass. Histopathologic review of the lesion was consistent with orbital varices. CONCLUSIONS: Although orbital varices usually are found in adults, they should be considered in the differential diagnosis of orbital lesions in children. Observation is usually warranted, but surgical intervention may be necessary in advanced cases.

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It is known that in respiratory burst oxidase preparations engaged in O2- production, cytochrome b558, a characteristic oxidase component, is partly reduced. This result has been interpreted in terms of a mechanism in which cytochrome b558 functions as an electron-carrying component of the respiratory burst oxidase, its level of reduction reflecting a steady-state partitioning of the cytochrome between reduced and oxidized forms as it ferries electrons from NADPH to oxygen. Kinetic arguments based on this interpretation have supported the proposal that the cytochrome is reduced at a rate sufficient to account for the rate of O2- production by activated neutrophils. We have confirmed the partial reduction of cytochrome b558 in neutrophil cytoplasts and in oxidase preparations exposed to NADPH, but have found that the reduction of the cytochrome bears no apparent relation to the activity of the oxidase, and can occur when NADPH is added to neutrophil membrane preparations that are unable to manufacture O2-. We therefore conclude that the NADPH-dependent reduction of cytochrome b558 seen in these preparations is unlikely to be a reflection of a catalysis-related steady state and that inferences drawn from such observations regarding the kinetic competence of the cytochrome may need to be reconsidered.

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