OPHTHALMOLOGICA

Selective Retina Therapy

Selective retina therapy (SRT), including retreatment if necessary, might be a valuable treatment alternative for central serous chorioretinopathy (CSC), even in chronic-recurrent cases, the results of a new study suggest. The two-centre trial included 10 patients with acute CSC and 16 patients with chronic-recurrent CSC. All underwent SRT with a prototype laser system with adjustable pulse duration. In patients with acute CSC, all had completely resolved fluid and mean visual acuity (VA) increased from 76.6 ETDRS letters to 85.0 ETDRS letters three months after SRT. In the 16 patients with chronic-recurrent CSC, subretinal fluid was absent in three (19 per cent) and leakage had stopped in six (38 per cent) but VA improved only slightly, from baseline 71.6 to 72.8 ETDRS letters. Among six patients with persistent leakage who underwent repeat SRT, subtretinal fluid resolved in five patients (83.3 per cent) after only 25 days. C Framme et al, “Selective Retina Therapy in Acute and Chronic-Recurrent Central Serous Chorioretinopathy”, Ophthalmologica 2015; 234:177-188.

Anti-VEGF and arterial thomboembolic events

The findings of an in vitro study indicate that exposure of platelets to ranibizumab or bevacizumab does not increase platelet activation and aggregation, which are critical processes in the pathogenesis of arterial thromboembolic events. However, high levels of bevacizumab may prevent platelet activation, which may explain the increased risk of bleeding associated with high doses of the anti-VEGF agent. In the study, platelets were isolated from healthy volunteers and exposed to different concentrations of ranibizumab, bevacizumab or their solvents for 10 or 30 minutes prior to the addition of TRAP (25μM), PAR-4-AP (25μM) or thrombin (0.02U/ml). All ranibizumab concentrations as well as the bevacizumab concentration of 3.0μg/ml had no influence on platelet activation and aggregation. On the other hand, the highest level of bevacizumab caused a down-regulation of platelet activation markers. B Sobolewska et al, “Different Effects of Ranibizumab and Bevacizumab on Platelet Activation Profile”, Ophthalmologica 2015; 234:195-210.

Intra-Arterial Chemotherapy

Intra-arterial chemotherapy (IACT) in eyes with retinoblastoma is efficient and repeatable and reduces the need for enucleation and radiotherapy with limited toxicity, a retrospective study indicates. A total of 56 eyes of 46 consecutive patients (30 males and 16 females) were included in the study. The enucleation-free survival rate following IACT was 56.7 per cent after a median follow-up time of 11.9 months (range 0.27-27.6 months). C Akyüz et al, “Intra-Arterial Chemotherapy for Retinoblastoma: A Single-Center Experience”, Ophthalmologica 2015; 234:211-217.