Dalteparin versus aspirin in recent-onset branch retinal vein occlusion: a randomized clinical trial.

BACKGROUND: Retinal vein occlusion is the second most common vascular disease of retina after diabetic retinopathy, affecting 1.6% of the population above the age of 40. The aim of this study was to compare the effect of dalteparin and aspirin in patients with recent-onset branch retinal vein occlusion. METHODS: A randomized clinical trial was conducted on patients with branch retinal vein occlusion of less than 30 days' duration. Ophthalmic, systemic, and hematologic evaluations were made. Visual acuity was measured with Early Treatment Diabetic Retinopathy Study chart. Patients in the dalteparin group received subcutaneous dalteparin 100 IU/kg twice daily for 10 days, then 100 IU/kg once daily for another 10 days while the patients in the aspirin group were given aspirin 100 mg daily throughout the study. RESULTS: Seventy-eight patients were enrolled, 37 in the dalteparin and 41 in the aspirin group. The patients were followed for six months. The visual outcomes of the two groups were compared. Although dalteparin improved mean visual acuity slightly more than aspirin, no statistically significant differences were found between the groups at one (P=0.37), two (P=0.16), three (P=0.11), or six (P=0.13) months. Resolution of macular edema and development of new vessels made no statistically significant difference between the groups [(P=0.08) and (P=0.49), respectively]. CONCLUSION: In recent-onset branch retinal vein occlusion, no significant difference was found in the final visual acuity between the patients treated by dalteparin or aspirin. A further study with larger sample size is recommended.

The impact of macular laser photocoagulation on contrast sensitivity function in patients with clinically significant macular edema.

BACKGROUND: Contrast sensitivity is an important aspect of visual function and is even more important for ordinary daily tasks than visual acuity. Contrast sensitivity function may be deteriorated to a significant level in diabetic retinopathy, especially in diabetic macular edema. The objective of this study was to determine the impact of macular laser photocoagulation-as the standard treatment of clinically significant macular edema-on contrast sensitivity function. METHODS: In a prospective noncomparative interventional case series, 17 patients with clinically significant bilateral macular edema and no history of prior macular laser photocoagulation were enrolled. Baseline visual acuity, contrast sensitivity function, and fluorescein angiography were obtained and reassessed three months after macular laser photocoagulation. RESULTS: Clinically significant macular edema resolved in 22 (65%) of 34 eyes, three months after their first session of macular laser photocoagulation. The mean pretreatment visual acuity was 24.5/40 (0.21 logMAR) +/-10.3/40. Three months after macular photocoagulation, visual acuity remained stable in 19 eyes, decreased in 12 eyes, and increased in three eyes. The mean post-treatment visual acuity was 24/40 (0.24 logMAR) +/-10.8/40. There was a statistically significant (P = 0.02) decrease in visual acuity following laser therapy. In subgroup analysis, this decrease in visual acuity was only observed in those with unresolved clinically significant macular edema. The mean contrast sensitivity threshold increased in all spatial frequencies by three months after macular photocoagulation. The maximum rise was observed in the frequency of 6.4 cycles per degree in the mid range of frequencies, with a pretreatment mean of 9.41 dB and a post-treatment mean of 11.50 dB (P<0.05). CONCLUSION: Contrast sensitivity function improved after macular laser photocoagulation in clinically significant macular edema patients.

Laser in situ keratomileusis and diode thermal keratoplasty for correction of hyperopia from +5.00 to +10.00 diopters.

PURPOSE: To evaluate the effects and safety of laser in situ keratomileusis (LASIK) and diode thermal keratoplasty (DTK) for correction of moderate to high hyperopia (+5.00 to +10.00 D). METHODS: This prospective study included 30 eyes of 15 patients who had LASIK-DTK bioptics. The median age of the patients was 50.5 years. LASIK was performed using a Nidek EC-5000 excimer laser system and DTK by a Prolaser DTK laser, 2 months after LASIK. Follow-up ranged from 9 to 12 months (mean, 10.5 mo). RESULTS: The mean preoperative spherical equivalent refraction was +8.25 +/- 0.25 D and mean postoperative was +1.00 +/- 0.50 D. The preoperative best spectacle-corrected visual acuity (BSCVA) was < or = 20/40 in 10 eyes and > or = 20/25 in 20 eyes. Postoperatively, BSCVA was < or = 20/40 in 8 eyes and > or = 20/25 in 22 eyes. No significant intra- or postoperative complications occurred. CONCLUSION: LASIK-DTK bioptics for correction of moderate to high hyperopia (+5.00 to +10.00 D) was safe and effective. In this method, two different ablative and non-ablative laser systems were used to compensate for regression, which is the most important concern in the correction of hyperopia.

Long-term effect of dalteparin in the prevention of neovascularization of iris in recent-onset central retinal vein occlusion.

BACKGROUND: To compare the long-term effect of dalteparin in the prevention of neovascularization of iris in recent-onset central retinal vein occlusion with that of aspirin. METHODS: A randomized controlled clinical trial was conducted on patients with central retinal vein occlusion of less than 30 days duration. Patients in the dalteparin group received subcutaneous dalteparin 100 IU/kg twice a day for 10 days, and then 100 IU/kg once a day for another ten days. In the aspirin group the patients received 100 mg aspirin daily throughout the study. RESULTS: Forty seven patients were enrolled, 24 in the dalteparin group and 23 in the aspirin group, and were followed up for one year. One (4.1%) of the 24 patients in dalteparin group, and 9 (39.1%) of 23 patients in aspirin group developed iris neovascularization. the difference was significant (P=0.0001). The visual outcomes of the two groups were compared, and a significant difference was found (P=0.016). CONCLUSION: Patients treated with dalteparin within 30 days of the onset of central retinal vein occlusion were less likely to develop neovascularization of iris. There was also a significant difference in the visual acuity between two groups.