Surgical treatment of cerebellar arteriovenous malformation (author's transl)

Abstract

Clinical analysis and surgical therapy of cerebellar arteriovenous malformation (AVM) were studied in 13 patients, consisting of 6 males and 7 females. Ages of the patients ranged from 6 to 64 years. The AVM manifested itself as subarachnoid hemorrhage in all cases, and consciousness was impaired in 9 patients. Feeding arteries were the superior cerebellar artery (SCA) in 3, the posterior inferior cerebellar artery (PICA) in 6, the anterior inferior cerebellar artery (AICA) and PICA in 2, the SCA and AICA in one the SCA and PICA in one patient. The nidus was located at the cerebellar hemisphere in 5, at the vermis in 4, at the cerebellopontine (CP) angle in 2 and over the cerebellar hemisphere extending to the vermis in 2 patients. The different surgical approaches were applied depending on the location of the AVM. When in was located over the superior surface of the cerebellar hemisphere or at the CP angle, operations were carried out through the subtemporal transtentorial approach with the patient in the lateral position. The tentorium was incised posterior to the vein of Labbe in cases of AVM at the superior surface of cerebellar hemisphere, and anterior to the vein of Labbe in cases of AVM at the CP angle. To avoid ischemic changes of the pons a temporary clip was applied on the cortical branch of the SCA and the main trunk of the SCA around the pons was spared. Difficulty in surgical management depended upon the relative location of the feeding artery to the trochlear nerve. In the cases of AVM at the CP angle, management of the trigeminal and facial nerves became a problem, but, since the feeding artery was easily managed, hardly any detectable cranial nerve palsy was present postoperatively. For the AVM located at the inferior surface of the cerebellar hemisphere and vermis the AVM was approached through the suboccipital route with the patient in sitting position. Postoperatively mild trochlear nerve palsy was observed in 2 patients, facial nerve palsy in one and cerebellar signs in 5 patients. In a few months. however, these symptoms became almost undetectable. As the result of operation 10 out of 13 patients recovered to the state before the onset of the disease. One patient remained unable to work, but was able to care for herself. Of the total, 12 patients underwent total removal of the AVM. The last patient in whom a small portion of the AVM was left undisected died of postoperative bleeding.