A Case of Bilateral Occipital Lobe Infarcts Following Indian Tree Viper Bite

permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. According to the World Health Organization (WHO), approximately 35,000 to 50,000 deaths are attributed to snake-bites in India each year. Annually, more than 2,000,000 snake-bites are reported in India. 1 The leading cause of fatal snakebite in India is the Viperidae species consisting of Russell's viper (Daboia russelli) and saw scaled viper (Echis carinatus). 2 Local cellulitis, renal failure, and systemic hemorrhage are the common clinical manifestations of a viper bite. 2 Neurological se-quelae due to cerebral infarction are rare, 3 and there are few reports of posterior circulation ischemic infarction. Indian tree viper (Trimeresurus gramineus) is a venomous pit viper species found only in southern India. Herein, we report a case of posterior circulation infarct involving bilateral occipital lobe following Indian tree viper bite. A 58-year-old otherwise healthy man, an agricultural worker native to Coorg district, Karnataka, was bitten by a snake on the right foot while working in the field. The snake was identified as Indian tree viper as per the descriptions given by the patient and his relatives. He had mild pain at the site of the bite and was on native medicines. On the third day following the snakebite, the patient developed sudden diminution of vision in both eyes. There was no history of redness, pain, or discharge in both eyes. He was alert and did not show limb weakness. He did not deny his diminution of vision in both eyes. He visited the local hospital and was referred to a larger hospital for further evaluation after 2 weeks. He received three vials of polyvalent anti-snake venom (ASV). At the time of admission, his pulse rate was 76 beats per minute, blood pressure was 130/82 mmHg, and respiratory rate was 22 cycles per minute. Local examination showed two fang marks with features suggestive of cellulitis on the dorsum of the right foot. The patient was alert and oriented. Neurological examination was normal except for decreased visual acuity (right/left eye, 6/60 by Snellen's visual acuity chart) with intact direct and con-sensual light reflexes. Fundus evaluation was normal. Laboratory results showed that hemoglobin was 12.2 gm/dL, total leu-kocyte count was 16,500/mm 3 with 70% neutrophils, and plate-let count was 215,000/mm 3. Liver and renal function tests, elec-trolytes, urine examination findings, and coagulation parameters were within normal limits. Electrocardiogram and chest ra-diogram …