OPHTHALMOLOGICA

Update on Coats’ disease

Coats' disease is rare condition of uncertain aetiology which can be difficult to diagnose in its early stages, according to recent review of the literature on the topic. An idiopathic, progressive condition, it is characterised by retinal telangiectasia and exudates which can cause retinal detachment. Its diagnosis can be challenging because it has features in common with many other retinal disorders. However, retinoblastoma is by far the most important lesion to rule out. There are several well-established treatment modalities for Coats’ disease, starting with laser photocoagulation and cryotherapy, for mild to moderate stages of the disease, to vitrectomy, for the advanced stages. In recent years, various investigators have used anti-VEGF agents as adjuvant therapy with variable results.

(Ghorbanian et al, Ophthalmologica 2012; DOI: 10.1159/000336906).

Uveal melanoma and enucleation

Overall mortality and metastasis-free survival are not significantly lower in uveal melanoma patients who undergo proton beam radiotherapy than they are in patients who undergo enucleation, according to the results of a retrospective non-randomised study. The study involved 132 consecutive patients with stage T3 and T4 choroidal melanoma. At five years’ follow-up, the cumulative all-cause mortality, melanoma-related mortality and metastasis-free survival there was no statistically significant difference between the two treatment groups. Moreover, 74 per cent of patients treated with proton beam radiotherapy retained their eyes at five years’ follow-up. Furthermore, best corrected visual acuity was 0.1 or better in 47.5 per cent of the retained eyes at 12 months’ follow-up, and in 32 per cent of the retained eyes at 60 weeks’ follow-up.

(Mosci et al, Ophthalmologica 2012; DOI: 10.1159/000334401).

New microcatheter for drug delivery

The results of a prospective study indicate that a new microcatheter can provide a safe and effective means of delivering steroids and anti-VEGF agents to the submacular suprachoroidal space in eyes with advanced age-related macular degeneration (AMD). The study involved 21 eyes of 21 patients with choroidal neovascularisation (CNV) secondary to advanced, exudative AMD. All underwent a single injection of a combination of bevacizumab and triamcinolone into the submacular suprachoroidal space using the new microcatheter. In all cases the researchers were able to perform the injection successfully and atraumatically without any serious intraoperative or postoperative complications such as suprachoroidal haemorrhages. The study’s authors noted that direct drug delivery to the choroid can potentially increase local tissue drug levels and drug efficacy for the treatment of AMD and other diseases associated with CNV.

(Tetz et al Ophthalmologica 2012; DOI: 10.1159/000336045).

Good and bad polymorphisms

Polymorphisms in the gene for the receptor for advanced glycation end products (RAGE) can increase or reduce the odds of retinopathy developing in patients with diabetes mellitus, according to a meta-analysis of research conducted to date. The meta-analysis of studies derived from PubMed and Web of Science (up to August 31, 2011) included six articles investigating the -429T/C polymorphism, seven investigating -374T/A polymorphism and five investigating Gly82Ser in patients with diabetic retinopathy. An estimation of pooled odds ratios showed that there was a positive correlation between the RAGE -374T/A polymorphism and retinopathy in patients with Type 2 diabetes, but there was a negative correlation between the -374AA allele and retinopathy in Type 2 diabetes. The analysis also indicated that the RAGE Gly82Ser polymorphism may increase the risk of diabetic retinopathy in Asian populations.

(Yuan et al, Ophthalmologica 2012; DOI: 10.1159/000335628).