Long-term outcomes of heavy silicone oil tamponade for complicated retinal detachment.

PURPOSE: To assess the long-term success rates and complications of heavy silicone oil tamponade (Oxane HD) in the management of complicated retinal detachment with proliferative vitreoretinopathy (PVR). METHODS: Twenty-one eyes of 21 patients with complicated retinal detachment and PVR were included in this study. Vitreoretinal surgery with heavy silicone oil (Oxane HD) tamponade was performed in all patients. Heavy silicone oil was injected by perfluorocarbon liquid-air-silicone oil exchange, and was removed after 3 months. The main outcomes of the surgery including the success and complication rates were evaluated during the mean follow-up period of 11.4+/-0.88 months. Wilcoxon signed ranks test was used for statistical analysis of visual acuity changes. The outcomes of our study were compared with those of the previous studies. RESULTS: All eyes had complicated retinal detachment with PVR Grade C3 or worse. Retinal detachment was rhegmatogenous in 6 eyes, secondary to previous detachment surgery in 11 eyes, secondary to proliferative diabetic retinopathy in 3 eyes, and secondary to perforating eye injury in 1 eye. The overall anatomic success rate was 80.9% at the end of the follow-up period. The overall visual success rate was 42.8%, with no statistically significant difference from baseline (p>0.05). Postoperative complications included severe reproliferation (4 eyes), intraocular pressure rise (3 eyes), anterior dislocation of silicone oil (2 eyes), posterior subcapsular cataract formation (4 eyes), vitreous hemorrhage (1 eye), rubeosis iridis (3 eyes), optic atrophy (1 eye), and ocular pain and photophobia (21 eyes). CONCLUSIONS: According to the results of this study, vitreoretinal surgery with temporary heavy silicone oil tamponade appears to increase the anatomic success rates with minimal complication rate in cases with complicated retinal detachment and PVR.

Serum cytotoxin and oxidant stress markers in N-acetylcysteine treated thioacetamide hepatotoxicity of rats.

N-acetylcysteine (NAC) is a glutathione precursor used to treat several clinical conditions where intracellular oxidant-antioxidant balance is disturbed, among which, acetaminophen induced hepatotoxicity may be counted. In this study, administering thioacetamide (TAA) as a hepatotoxic agent, a rat model of hepatotoxicity has been established, to investigate some of the immune mediated basic oxidant-antioxidant homeostatic mechanisms involved, and potential serum markers for follow-up of disease and treatment. To do this, four experimental groups receiving saline/saline, saline/NAC, saline/TAA and NAC/TAA as intraperitoneal injections, have been formed. Rat serum tumor necrosis factor-alpha (TNF-alpha), Interleukin1-beta (IL1-beta), malondialdehyde (MDA) as a measure of final oxidant damage and the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) have been assayed. Hepatocellular damage has been measured via the biochemical estimates ALT, AST and LDH as well as histopathological grading. It was found that both TNF-alpha and IL1-beta were significantly elevated in saline/TAA receivers (P<0.01) when compared to NAC/TAA receivers. Serum MDA was also increased in TAA receivers in addition to SOD (P<0.05) and GSH-Px (P<0.05). Serum nitrite levels have also been assayed to give an estimate of nitric oxide that is suggested as a counter-balancer of oxidant stress. NAC/saline receivers had the highest levels of nitrites in the serum (P<0.05). Our results indicate that part of the hepatocellular injury to rat liver, induced by TAA is mediated by oxidative stress caused by the action of cytokines imparted by the enzymatic SOD and GSH-Px and non-enzymatic gaseous nitric oxide mechanisms causing an alleviation on administration of NAC. In addition, TNF-alpha, IL1-beta, MDA, SOD, GSH-Px and nitrites are potential candidates of serum indicators for monitorization of pathophysiological stage of liver disease.