Evaluation of Clinical Usability and Effects of Photochromic Lenses

PURPOSE: To evaluate stability and effects of photochromic lenses in light-sensitive patients. METHODS: Analyzing 65 patients, this research employed a standardized survey, fundus examination, and slit-lamp biomicroscopy to evaluate the changes in photophobia, tears, asthenopia, and the deterioration of outdoor visual acuity after wearing photochromic lenses for one month. Measurement of visual acuity was performed outdoors at noon on a bright day using Dr. Hahn's standard test chart for 3 m. RESULTS: Photochromic lenses, considerably decreased photophobia, tears, and asthenopia. The "normal" visual acuity of 38 patients was established without photochromic lenses. Re-examination after the lenses had been worn for a specified period of time showed that 29 subjects could discern at least one line higher than their "normal" acuity. CONCLUSIONS: Photochromic lenses reduced photophobia and the disabling effect of bright light such that comfort was increased. Not only did the lenses improve vision, they also enhanced the overall quality of vision.

A Case of Atypical Valsalva Retinopathy after Strenuous Exercise

PURPOSE: To report a case of recurrent bilateral preretinal hemorrhages in a healthy male with no previous history of systemic or ocular diseases and to review the relevant literature. METHODS: History taking, measurement of visual acuity and intraocular pressure, slit-lamp examination, fundoscopy, and fluorescein angiography were performed in a 15-year-old male who had experienced a sudden decrease in visual acuity in both eyes after a couple of strenuous exercises in school. RESULTS: Best-corrected visual acuity (BCVA) was 0.9 in the right eye and 0.2 in the left, and bilateral premacular hemorrhages were observed. Most of the preretinal hemorrhages were completely resolved by the sixth week and visual acuity in the left eye improved to 0.6. Nine months after the initial event, preretinal hemorrhages recurred bilaterally, worse in the left eye, and BCVA decreased to 0.3 in the right eye and 0.02 in the left eye. We performed Nd: YAG laser disruption of the internal limiting membrane in the left eye. Four weeks after the procedure, most of the preretinal hemorrhages were resolved and visual acuity in the left eye improved to 0.2. CONCLUSIONS: Clinical improvement was achieved after Nd: YAG laser disruption of the internal limiting membrane in a case of recurrent bilateral preretinal hemorrhages.

ReVersible Change of Vision in Patients Receiving Deferoxamine

PURPOSE: To report 2 cases of acute visual neurotoxicity in patients with paraquat poisoning receiving deferoxamine. METHODS: A 48-year-old woman and a 37-year-old man received intravenous infusion of deferoxamine at 3g/day for 7 days for treatment of paraquat poisoning. They presented with severely impaired visual acuity, generalized constriction of visual field, and decreased amplitude of visual evoked potential. They improved clinically upon drug-withdrawal. CONCLUSIONS: Deferoxamine is an effective agent for treatment of paraquat poisoning, but can cause visual neurotoxicity. We recommend careful regulation of the deferoxamine dosage and serial visual monitoring in patients receiving the drug.

Multilayer Amniotic Membrane Transplantation for Corneal Ulcer Perforation

PURPOSE: To evaluate the clinical outcome of multilayer amniotic membrane transplantation (AMT) in the cornea which was perforated or had impending perforation due to corneal ulcer. METHODS: Human multilayer amniotic membrane transplantation were performed in patients with perforation or impending perforation of cornea due to herpetic keratopathy (2 eyes of 2 patients) and fungal ulcer (1 eye). The surgical procedure consists of the following steps: First, all cellular debris was carefully removed from the base and the walls of the ulcer and loosened epithelium. In addition 1 to 2 mm zone is created around the ulcer by removal of healthy, adherent epithelium overlaying the normal Bowman membrane. Depending on the depth and the configuration of the ulcer, three or more of small pieces of human amniotic membranes are stacked one above the others to fill the cavity of the ulcer. Finally, a larger piece of membrane is trimmed to cover the ulcer and then secured with interrupted 10-0 nylon suture. RESULTS: The corneal perforations were prevented and the stable ocular surface were achieved in all patients. CONCLUSIONS: Human multilayer amniotic membrane transplantation is a useful treatment prior to corneal transplantation and considered as an alternative treatment to keratoplasty for perforation or impending perforation of corneal ulcer.

Visual Field Changes in Children with Vigabatrin Treatment

PURPOSE: Recently, several reports have documented persistent visual field changes associated with long-term use of Vigabatrin, an antiepileptic drug. Epilepsy is a common disease in children, therefore we investigated perimetric changes in children who were on Vigabatrin treatment. METHODS: Total 36 eyes of 18 patients who had been treated with Vigabatrin were tested with Humphrey Field Analyzer. The visual fields were assessed using central 30-2 threshold test and peripheral 60-4 threshold test. RESULTS: In central 30-2 threshold tests, 13 eyes(40.6%) showed mild visual field constrictions and 4 eyes(12.5%) showed severe visual field constrictions. In peripheral 60-4 threshold tests, 23 eyes(71.8%) showed visual field changes. CONCLUSIONS: Asymptomatic visual field loss may develop in Vigabatrin-treated children. Regular examinations of the visual field is warranted for Vigabatrin-teated children.

Treatment of a Traumatic Carotid Cavernous Fistula and Dural Shunt Using Microcoils

Carotid cavernous fistulas and dural shunts are abnormal communications between the cavernous sinus, dural veins and the carotid artery.Ocular signs of these are decreased visual acuity, exophthalmos, chemosis, limitation of eye movement, venous congestion and diplopia, etc. We treated a patient with traumatic carotid cavernous fistula and dural shunt by embolization using platinum microcoils and report with a review of the literatures.

Refractive States of 3~4 Year Olds that Underwent Cryotherapy in ROP

The previous researches proved that the incidence of myopia in cryotreated retinopathy of prematurity[ROP]eyes is higher than that of non-treated ROP eyes. The authors compared refractive states, anterior-posterior axial length and other contributing factors of treated eyes with those of nontreated eyes at the same age group between 3~4 years old. In the cases of cryotreated group, the mean refractive error was -3.48 +/-4.02D. Among 42 treated eyes, 30 eyes became myopic[71.4%]. The mean axial length was 22.46 +/-1.43mm. The mean length of posterior segment was 15.53 +/-1.33mm. In contrast, the mean refractive error was 1.09 +/-1.04D in non-cryotreated group. Three eyes among 42 untreated eyes developed myopia [7.1%]. The mean axial length was 21.02 +/-1.17 mm. The mean length of posterior segment is 14.09 +/-0.97mm. We concluded that myopia could be developed in cryotreated ROP eyes by the elongation of eyeball, specifically of posterior segment.