Successful argon and diode laser photocoagulation treatment of an iris varix with recurrent hemorrhage.

PURPOSE: To report successful laser treatment of an iris varix. 
 METHODS: A 66-year-old man presented with an incidental finding of a cystic lesion within the iris stroma in his right eye. He developed a blood-filled and partly thrombosed tumor of the iris stroma and complained about blurred vision due to spontaneous hyphema during follow-up. 
 RESULTS: Ultrasound biomicroscopy showed a prominent and liquid-filled lesion within the iris stroma. Iris fluorescein angiography revealed a thrombosed iris tumor without intrinsic vascularization or feeding vessels. Therefore, diagnosis of an iris varix was made clinically. Recurrent bleeding occurred during follow-up and led to decreased visual acuity. Combined argon and diode laser photocoagulation was successful in terminating rebleeding and resulted in a scarred iris varix. 
 CONCLUSIONS: Symptomatic iris varices can be treated safely by combined argon and diode laser photocoagulation, facilitating a less invasive approach than surgical excision.

Comparison of dynamic contour tonometry and Goldmann applanation tonometry in keratoconus.

PURPOSE: We performed a comparative study using Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) to measure intraocular pressure (IOP) in eyes with keratoconus. METHODS: IOP was measured in 114 eyes of 75 patients with keratoconus (51 men and 24 women; mean age, 36.1 ± 11.2 years) using GAT and DCT in randomized order. Central corneal thickness (CCT), minimal corneal thickness (MCT), and corneal topography were recorded using the Pentacam. Four groups according to Amsler's keratoconus classification were composed and analyzed for significant differences of CCT, MCT, GAT, and DCT results. RESULTS: Mean CCT in the 114 keratoconus eyes was 481.1 ± 46.2 µm (range, 334-601 µm). Mean MCT was 453.3 ± 56.3 µm (range, 239-573 µm). Mean IOP measured using GAT was 13.1 ± 2.9 mm Hg, whereas mean IOP measured using DCT was 14.8 ± 2.6 mm Hg. Neither the results for GAT nor those for DCT showed a significant correlation with CCT (Pearson correlation: P < 0.05). Multifactorial analysis revealed that CCT and MCT, but not GAT and DCT, results were significantly different in corneas of varying curvatures. CONCLUSIONS: This study shows that DCT measures IOP higher than GAT in eyes with keratoconus. In keratoconus, both methods seem to be independent of CCT and therefore are equally, but not interchangeably, applicable when monitoring IOP. Further analysis revealed that CCT and MCT are significantly different in corneas of varying Amsler grade.

Corneal epitheliotrophic capacity of three different blood-derived preparations.

PURPOSE: Serum eye drops have been successfully used in the treatment of severe ocular surface disorders. Fresh frozen plasma (FFP) and platelet concentrates have not yet been tested for use as eye drops, although they are easily available as quality-controlled products from blood banks and are routinely used for transfusion. To test whether FFP or platelet-derived growth factor solutions could be used for ocular surface diseases, we compared the epitheliotrophic capacity of platelet releasate and FFP with that of serum in cell culture models. METHODS: The concentrations of EGF, TGF-beta1, PDGF-AB, fibronectin, vitamin A and vitamin E in serum, FFP, and platelet releasate were evaluated with ELISA and HPLC. Corneal epithelial cells were incubated with the various preparations and cell proliferation, migration, and differentiation were evaluated by means of a luminescence-based adenosine triphosphate (ATP) assay, a colony dispersion assay, and scanning electron microscopy. RESULTS: Growth factor concentrations were significantly higher in platelet releasate than in serum and were lowest in FFP. Fibronectin and vitamins were found in higher concentrations in serum than in FFP and were lowest in platelet releasate. Cell proliferation was best supported by platelet releasate followed by serum and FFP; however, cell migration and differentiation were better supported by serum than by platelet releasate and FFP. The reduced nutrient capacity of FFP was in part found to be due to an antiproliferative effect of citrate used as an anticoagulant in the production process. CONCLUSIONS: Platelet releasate but not FFP may offer additional potential for the treatment of severe ocular surface disease. Platelet releasate may be suitable as a novel treatment option for ocular surface disease with a superior effect on cell growth.