Comparison of Clinical Outcomes of Argon Laser Versus Selective Laser Trabeculoplasty in POAG

PURPOSE: To compare the clinical outcomes between patients undergoing argon laser trabeculoplasty (ALT) and those undergoing selective laser trabeculoplasty (SLT). METHODS: Sixty-one eyes of 61 patients with primary open-angle glaucoma who were treated with more than 1 kind of antiglaucoma medication eye drop were enrolled in this study. Thirty-five eyes of 35 patients were treated with argon laser trabeculoplasty (ALT). Twenty-six eyes of 26 patients were treated with selective laser trabeculoplasty (SLT). The mean IOP at 1, 3, 6, and 12 months and the success rate of treatment at the 12-month follow-up period were evaluated in all patients. RESULTS: At 12 months postoperative, the ALT group had a mean IOP of 16.53+/-2.58 mmHg with a mean IOP reduction of 35.27%, while the SLT group had a mean IOP of 18.40+/-5.61 mmHg with a mean IOP reduction of 17.37%. The success rates of treatment defined as definition 1 were 62.85% in ALT and 62.50% in SLT, and the success rates defined as definition 2 were 51.42% in ALT and 46.15% in SLT. CONCLUSIONS: There were no significant differences in the IOP lowering effect or success rates between the ALT and SLT patients at 12 months postoperatively.

A Case of Fungal Keratitis Caused by Colletotrichum Species / 대한임상미생물학회지

Colletotrichum is mainly a fungal pathogen of plants, but sporadic cases of human infection have been reported recently. Most of them are fungal keratitis and only a few cases have been reported worldwide. A 63-year-old female farmer developed foreign body sensation and watering in her left eye following trauma by rice leaves. At presentation, her visual acuity decreased and corneal ulcer and inflammation in anterior chamber were observed on a slit lamp examination. Numerous hyphae were found on Gram stain and a rapidly growing mold with cup-shaped acervuli and falcate and nonseptate conidia was observed on fungal culture. As morphological findings did not lead to definite differentiation of the organism, sequencing of the D1-D2 domain of 28S rDNA was performed. It proved to be Colletotrichum species and the patient was treated with amphotericin and natamycin eye drop, but complicated by acute glaucoma. This is the first report of Colletotrichum keratitis in Korea and suggests that its infection should be considered in patients with fungal keratitis.

Comparison of Photorefractive Keratectomy and Laser Epithelial Keratomileusis for Low to Moderate Myopia

PURPOSE: To compare the efficacy and safety of photorefractive keratectomy with laser epithelial keratomileusis, for low to moderate myopia. METHODS: Patients with a manifest refraction less than -6.0 diopters were enrolled in this study. Patients were treated with photorefractive keratectomy (47 eyes) or laser epithelial keratomileusis (42 eyes). Preoperative and postoperative uncorrected visual acuity, refractive errors, keratometry, residual central corneal thickness, epithelial healing time, and corneal haze were evaluated for a 1 year follow-up period. RESULTS: There were no significant differences between photorefractive keratectomy and laser epithelial keratomileusis in uncorrected visual acuity, refractive errors or correction of refractive errors. Residual central corneal thickness increased until 6 months postoperative and thereafter in both photorefractive keratectomy and laser epithelial keratomileusis groups. There were no significant changes in keratometry after postoperative 1 month. Epithelial healing time of photorefractive keratectomy was shorter than that of laser epithelial keratomileusis. Corneal haze score had a peak at 1 month postoperative and then decreased rapidly until 3 months postoperative, it was stable after 6 months. Corneal haze score at 1 month was less than 0.5 in both groups and did not disturb visual acuity. CONCLUSIONS: Photorefractive keratectomy and laser epithelial keratomileusis have an equal effect in correction of visual acuity and refractive errors. They have equivalent levels of safety as measured by postoperative residual central corneal thickness and corneal haze. Both procedures are effective methods to correct low to moderate myopia.

Effects of Double Silicone Tube Intubation for Nasolacrimal Duct Obstruction in Adults

PURPOSE: To evaluate the effectiveness of double silicone tube intubation in the treatment of nasolacrimal duct (NLD) obstruction in adults. METHODS: We treated 159 eyes of 159 patients with NLD obstruction. The resolution of preoperative symptoms and signs of NLD obstruction was evaluated two months after the removal of the silicone tubes. RESULTS: The mean age of patients was 57.9 years and the mean follow-up period was 8.5 months. The symptoms and signs of NLD obstruction were reduced in 85.6% of the patients. The partially obstructed group showed a higher lacrimal patency rate (93.0%) than the completely obstructed NLD group (82.7%). There was no discomfort due to the double silicone tubes. There was a punctal slit in 13 eyes, prolapse of silicone tubes to ocular side in 5 eyes and 3 eyes had punctum to punctum adhesion after the procedure. CONCLUSIONS: Double silicone tube intubation is an effective therapy in adults with NLD obstruction, especially for those with partially obstructed NLD. Indications were seen that these tubes keep greater dilatation of the NLD.

The Long-Term Effects of Soft Contact Lens Wear on Corneal Thickness, Curvature and Endothelium

PURPOSE: To investigate the effects of long-term contact lens (CL) wearing on corneal thickness, curvature, and endothelium. METHODS: Using ultrasonic pachymetry, Orbscan topography and specular microscopy, we evaluated the cornea of 53 subjects who had used soft CL for more than 5 years compared with 47 controls who had never used CL. RESULTS: There was a significant decrease of central corneal thickness in CL wearers. The difference of central corneal thickness between the two groups was 16.39 micrometer. The percentage of central corneal thickness less than 500 micrometer was 24.5% in the CL wearers and 12.2% in the controls. The mean corneal thickness of the CL wearers in the center and eight peripheral areas, as measured with Orbscan topography, was significantly reduced by about 7.28 to 17.87 micrometer compared with that of the controls. The corneal curvature and elevation were significantly steeper in the CL wearers than in the controls but no difference in the mean corneal astigmatism was found between the two groups. Endothelial density and percentage of hexagonal cells were decreased and the coefficient of cell area variation was increased in the CL wearers compared to the controls. The percentage of endothelial cell densities less than 2500 cells/mm2 was 24.5% in the CL wearers and 4.25% in the controls. CONCLUSIONS: Long-term soft contact lens use may have a significant effect on corneal thickness, curvatures and endothelial morphology.

Asymmetry Analysis of the Retinal Nerve Fiber Layer Thickness in Normal Eyes using Optical Coherence Tomography

PURPOSE: To investigate the asymmetry of the retinal nerve fiber layer thickness (RNFLT) with respect to the horizontal and vertical meridian and between the right and left eye in normal subjects. METHODS: The RNFLT was measured in 121 normal volunteers by optical coherence tomography (OCT). The RNFLT was analyzed by dividing the circle scanning area (diameter 3.4 mm) around the optic disc into 4 quadrants and 12 sectors. RESULTS: There was a significant difference between the RNFLT of the nasal and temporal quadrant in individual eyes. There was a significant difference between the RNFLT of corresponding sectors with respect to the vertical or horizontal meridian in individual eyes. The nasal and temporal RNFLTs were asymmetrical between the right and left eye in the quadrant and sector analysis. The RNFLT of the nasal and temporal quadrant was thicker in the right eye. The nasal and inferior RNFLT measured by OCT had a significant correlation with degree of refractive error. CONCLUSIONS: In normal subjects without significant anisometropia, there was significant asymmetry of the RNFLT for each eye as well as between the right and left eye.

Management of Prolapsed Silicone Tube Inserted for Treatment of Nasolacrimal Duct Obstruction

PURPOSE: To introduce a new surgical management for the prolapsed silicone tube into the ocular surface which was inserted for treatment of nasolacrimal duct obstruction. METHODS: Five eyes of 179 eyes treated with silicone tube intubation for nasolacrimal duct obstruction from May to December 2003 had a prolapsed silicone tube during the follow-up period. After local anesthesia, a Ritleng probe was inserted into the nasolacrimal duct. A polypropylene thread was passed into the Ritleng probe, and after removal of the probe, the thread was tied to a prolapsed silicone tube near a punctum and was pulled through the nose. The silicone tube was repositioned in the nasolacrimal duct. RESULTS: All the prolapsed silicone tubes were successfully repositioned without any significant complications. CONCLUSIONS: It is difficult to reposition a prolapsed silicone tube after silicone tube intubation for the treatment of nasolacrimal duct obstruction. We introduced an easy and effective method to reposition the prolapsed silicone tube.

Treatment of Conjunctival Nevus with Argon Laser

PURPOSE: To evaluate the clinical efficacy of Argon laser photocoagulation in patients with conjunctival nevus. METHODS: Twenty-seven patients (27 eyes) who were clinically diagnosed with conjunctival nevus from January to September 2003 were included in this study. The conjunctival nevus was eliminated by Argon laser after topical anesthesia with proparacaine. The power density varied between 200 and 400 mW and the spot size ranged from 100 to 300 microgram. The duration of argon laser was 0.15~0.2 sec. The spot count was varied according to the size and degree of pigment density of conjunctival nevus. The mean follow-up period was 7.0 months. RESULTS: The wounds after Argon laser treatment were completely healed within 1 week. Twenty-three eyes were treated completely with only one laser treatment but 4 needed an additional laser treatment for more satisfactory cosmetic results. There were no postoperative complications such as infections, conjunctival degeneration or recurrence. CONCLUSIONS: Argon laser treatment for conjunctival nevus has benefits such as no intraoperative hemorrhage, low recurrence rate, easier method and good cosmetic results.