Surgical treatment of thalamic arteriovenous malformations

The microsurgical excision of arteriovenous malformations located in the thalamic region in eight patients is reported. Six were located in the posterior aspect of the thalamus and two were located in the anterior. Hemorrhage occurred in all of the cases. Hemiparesis, hemianesthesia, and consciousness disturbance were the most typical clinical features. The supine position with the anterior transcallosal approach was used for anterior dorsal lesions, and the sitting position with the posterior interhemispheric approach was used for posterior dorsal lesions. Total removal was confirmed by angiography in seven patients, and incomplete removal was noted in one patient. There was one death in this group of patients. Memory disturbance was the most common postoperative complication. This complication showed considerable improvement with time. Other complications included homonymous hemianopsia (three patients), hemisensory loss (six patients), and transient hemiparesis (one patient). All survivors (seven patients) were able to return to their occupation after surgery. The vascular input, the location of the malformation, and clinical history are the contributory factors concerning operability. With the modern neurosurgical and anesthesiological facilities, surgical removal of thalamic malformations in selected cases is advisable.