Result of Retrosigmoid Sub-occipital Craniectomy in Patients with Acoustic Neurinoma in Shohada Hospital (1998-2006)

Acoustic neurinoma is a benign neoplasm of schwann cell source that mainly originate from vestibular branch of 8th cranial nerve. In this study we evaluated the result of suboccipital retrosigmoid surgery in patients operated in Shohada hospital from 1998 to 2006. This retrospective study was carried out using the hospital records of patient with suboccipital retrosigmoid operated in Shohada hospital between 1998-2006. The clinical information and outcome of surgery were extracted and then analyzed. A total of 80 patients (42men and 38 women) with mean age 45±7 years evaluated. The most common clinical presentation was hearing loss. In 93% of patients, the tumor size was greater than 3 cm. The location of the tumor was left side in 25 patients and right side in 50 patients, whereas in 5 patients it was bilateral. All of the patients had been operated with retrosigmoid craniectomy approach and tumor was totally resected in 87% of cases. Regardless of the the tumor size, the facial nerve had anatiomically been saved in 76.2% of patients. 6 patients (7%) died and temporary morbidity occured in 34% of patients which has been recovered by medical treatment. 59 patients were had accurately followed up. After 1 year of surgery, the functional condition of facial nerve was: Excellent 73/5%, good 22/5%, fair 6%. We demonstrated that facial nerve was considerably preservated in patients with acoustic neurinoma after operation. In this study, tumors were mainly large. Therefore, it is better to use CT Scan and MRI in patients in order to achieve the earlier diagnosis and appropriate treatment.