Objective: To investigate the advantage of cerebellomedullary fissure approach to resect the space occupying lesion in the fourth ventricle region and at the back of pons and to discuss the microsurgical skills.
Methods: The craniotomy is through the posterior fossa. To maximize the width of exposure, a long skin incision is made from the occipital protuberance down to the C4-5 level, and a free occipital bone flap is turned. The tonsils of cerebellum are reached by opening the tonsillovermian fissure and then moved upward so as to expose the operating field. Neoplasm in the fourth ventricle and at the back of pons was resected.
Results: Among the 23 cases, total resection was achieved in 20, and subtotal resection in 3.
Conclusion: The cerebellomedullary fissure approach can provide a panoramic view between the two lateral recesses and from the obex to the aqueduct without excision of neural tissue. During the operation, the inferior vermis is not incised. The vessels and nervous tissue are extracted at a minimum extent. Such a procedure is much safer.