Intraocular Lens Power Calculation after Refractive Surgery: A Comparative Analysis of Accuracy and Predictability

PURPOSE: To compare the accuracy of intraocular lens (IOL) power calculation using conventional regression formulae or the American Society of Cataract and Refractive Surgery (ASCRS) IOL power calculator for previous corneal refractive surgery. METHODS: We retrospectively reviewed 96 eyes from 68 patients that had undergone cataract surgery after keratorefractive surgeries. We calculated the formula with two approaches: IOL powers using the ASCRS IOL power calculator and IOL powers using conventional formulae with previous refractive data (Camellin, Jarade, Savini, and clinical history method) or without prior data (0, 2 and, 4 mm total mean power in topography, Wang-Koch-Maloney, Shammas, Seitz, and Maloney). Two conventional IOL formulae (the SRK/T and the Hoffer Q) were calculated with the single K and double K methods. Mean arithmetic refractive error and mean absolute error were calculated at the first postoperative month. RESULTS: In conventional formulae, the Jarade method or the Seitz method, applied in the Hoffer Q formula with the single K or double K method, have the lowest prediction errors. The least prediction error was found in the Shammas-PL method in the ASCRS group. There was no statistically significant difference between the 10 lowest mean absolute error conventional methods, the Shammas-PL method and the Barrett True-K method calculated with using the ASCRS calculator, without using preoperative data. CONCLUSIONS: The Shammas-PL formula and the Barrett True-K formula, calculated with the ASCRS calculator, without using history, were methods comparable to the 10 most accurate conventional formulae. Other methods using the ASCRS calculator show a myopic tendency.

Comparison of Blinking Patterns When Watching Ultra-high Definition Television: Normal versus Dry Eyes

PURPOSE: To analyze blinking patterns when watching an ultra-high definition (UHD) television and to compare the results between normal eyes and dry eyes. METHODS: A total of 59 participants aged from 13 to 69 years were instructed to watch a colorful and dynamic video on a UHD television for 10 minutes. Before and after watching the UHD television, we measured the best corrected visual acuities, autorefraction, tear-break-up-time, degree of corneal erosion and conjunctival hyperemia via slit lamp biomicroscopy. In addition, questionnaires for the evaluation of eye fatigue and symptoms of a dry eye were completed. The definition of dry eye syndrome was that the tear-break-up-time of one of the eyes was less than 5 seconds, conjunctival injection, or marked corneal erosion. The number of blinks and the duration of blinking were both measured and analyzed at the early and late phases of video-watching. RESULTS: After watching the UHD television in the normal eye group, the tear-break-up-time was significantly decreased (p < 0.001) and the degree of corneal erosion was significantly increased (p = 0.023). However, the subjective symptoms of participants were not aggravated (p = 0.080). There were no significant differences in blinking patterns in the dry eye group. On the other hand, in the normal eye group, the mean blinking time was significantly increased (p = 0.030). CONCLUSIONS: Watching an UHD television changes the tear-break-up-time, degree of corneal erosion, and blinking pattern in normal eyes, which may increase the risk of dry eye syndrome.

Radius-Maumenee Syndrome Presenting with Ocular Pain and Conjunctival Injection: A Case Report

PURPOSE: Radius-Maumenee syndrome (RMS) is characterized by idiopathic dilated episcleral vessels usually associated with glaucoma. The authors report a case of a 32-year-old Korean male with dilation of the episcleral vessels and glaucoma in both eyes. CASE SUMMARY: A 32-year-old Korean male presented with conjunctival injection and chronic pulsatile ocular pain in both eyes for 11 years. His best corrected visual acuity was 20/20 in both eyes. Slit lamp biomicroscopy showed episcleral venous engorgement in both eyes. Fundus photographs revealed superotemporal and inferotemporal retinal nerve fiber layer defects and Humphrey visual field testing showed superior nasal steps and paracentral scotomas in both eyes. He suffered from chronic eye pain in both eyes although he had applied glaucoma medication and his symptoms had worsened during the past year. Brain magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) revealed no evidence of carotid cavernous fistula or other orbital lesions. Due to the presence of episcleral venous engorgement, glaucoma and negative tests for other possible diseases, he was diagnosed with RMS. CONCLUSIONS: RMS is an idiopathic disease with episcleral vessel dilation and frequently associated with glaucoma. Its diagnosis is confirmed by eliminating other possible causes of episcleral venous engorgement.

A Case Report of Eyebrow Basal Cell Carcinoma Successfully Treated with 5% Imiquimod Cream

PURPOSE: Basal cell carcinoma is the most common malignant neoplasm of the skin. Periorbital basal cell carcinoma needs to be treated for cosmetic improvement and prevention of intraorbital invasion. Although surgical excision is a standard treatment, nonsurgical treatment using imiquimod cream, a topical immunomodulator, has been attempted. The authors report the first case of periorbital basal cell carcinoma successfully treated with imiquimod cream; to the best of our knowledge, similar cases have not been published to date in the Korean ophthalmology journals. CASE SUMMARY: A 73-year-old female visited our hospital for treatment of a biopsy-proven basal cell carcinoma in the right eyebrow. A flat, elevated, 1 x 1 cm-sized mass having central indentation was observed in the centromedial area of the right eyebrow. She was treated with 5% imiquimod cream once daily at night, 5 days per week for 6 weeks. Eight weeks after the treatment with imiquimod cream was discontinued, the mass was flattened and the cilia began to grow on the mass site. Under the impression of a partial regression, an additional 4 weeks of application was recommended. The mass disappeared more and her eyebrow became more normal. At the final follow-up 31 months after treatment, her right eyebrow appeared normal. CONCLUSIONS: Imiquimod cream may be a useful medication which can be used for complex periorbital basal cell carcinomas that are difficult to reconstruct after resection or surgical candidates with poor general condition.