Background. The aim of this study is to define the anatomic landmarks which are necessary for transcondylar approach and to determine the importance of these structures during surgical resection. Methods. 56 dry skulls were included in this study. Landmarks were detected. Some distances and angles, which were determined before, were measured and the anatomical structures were observed. 21 parameters were examined and analysed in totally 56 dry skulls using 56 foramen magnum, 112 hypoglossal canal and 112 occipital condyles. The landmarks which were used were the anterior and posterior borders of the occipital condyle, the medial and lateral margin of the occipital condyle, basion, opisthion, hypoglossal canal and posterior condylar canal. The measurements were made separately for the right and left sides. Results. The mean length of the occipital condyle was found as 23.1 mm. The distance betweeen the intracranial edge of the hypoglossal canal and anterior margin of the occipital condyle was measured as 11.2 mm in both sides. The distance betweeen the intracranial edge of the hypoglossal canal and posterior margin of the occipital condyle was measured as 12.5 mm at the right side and 12.6 mm at the left one. The mean length of the hypoglossal canal was measured as 10.5 mm at the right side and 10.6 mm at the left one. 14 hypoglossal canals were divided into two compartments by a septum. Conclusions. In transcondylar approach, the anatomical landmarks should be well known in order to make a safe occipital condyle resection. The distance betweeen the intracranial edge of the hypoglossal canal and posterior margin of the occipital condyle is important for a safe occipital condyle resection, and it was found to be 12.55 ±0.05 mm in our study. Approximately 12 mm occipital condyle resection can be made without giving damage to the neural tissue. This value is appropriate to the ½ of the occipital condyle.

Tuberculosis has been an important public health problem in both developing and develop nations. Tuberculosis of the central nervous system is rare. Tuberculosis meningitis and tuberculoma are the two most important manifestations of tuberculosis of the CNS. Intracranial tuberculomas may be solitary or multiple. Solitary tuberculomas may be indistinguishable from cranial abscess or primary brain tumor. It is necessary to rule out tuberculoma in patients with intracranial mass lesions. We present a case of tuberculoma mimicking a high grade glial tumor on magnetic resonance imaging and clinical presentation. A 30-year-old woman presented with one-month history of epilepsy. Cranial magnetic resonance imaging showed a left occipital peripheral ring-enhanced lesion with central necrosis. There was a strong suspicion of glial tumor. The lesion was totally excised with left occipital craniotomy. Histological examination of mass revealed a tuberculoma. The patient was treated with antituberculous chemotherapy.

The primary brain tumors associated with cerebral aneurysms are rare in neurosurgical practice. The present article constitutes an evaluation of the management of coexistent primary brain tumor and cerebral aneurysm. A retrospective study of three cases of primary brain tumor with cerebral aneurysm was performed. We evaluated the complications and clinic outcomes by assessing the clinical and imaging findings. Case 1 presented with a subarachnoid hemorrhage from an aneurysm of the anterior communicating artery, with an incidental left frontal oligodendroglioma. Case 2 presented with chronic headache due to left frontal convexity meningioma, with proximal internal carotid artery aneurysm which was found incidentally during preoperative magnetic resonance angiography. Case 3 was admitted to our hospital complaining of headache, memory disturbance, and weakness in her left lower extremity. Magnetic resonance imaging revealed right frontal lymphoma and an unruptured aneurysm at the left middle cerebral artery. Preoperative magnetic resonance imaging revealed right frontal lymphoma and unruptured left middle cerebral artery. The frequency of primary brain tumor and cerebral aneurysm coexistence is increasing due to improvements in high-resolution imaging. In these complicated cases, the management will differ according to each pathology present, and this is an important problem for a neurosurgeon.

Background. Laboratory training models are essential for developing and refining surgical skills prior to clinical application of spinal surgery. A simple simulation model is needed for young residents to learn how to handle instruments and to perform safe posterior lumbar approaches. Our aim is to present a practical laboratory model using a fresh sheep lumbar spine that simulates the pedicular screw fixation in spine surgery. Methods. The material consists of a fresh cadaveric spine from a 2-year-old sheep. A two-step approach was designed for posterior lumbar approaches including placement of lumbar pedicular screws. Results. The model simulates standard posterior lumbar pedicular screw fixation of the human spine. Conclusions. The cadaveric sheep spine represents a useful method to accustom trainees of neurosurgery and spine surgery residents and simulates posterior lumbar pedicular screw fixation performed in the human spine.

Grade 5 spondylolisthesis or spondyloptosis is a rare condition. Generally, the surgical management of spondyloptosis includes multi-staged procedures instead of one-staged procedures. One-stage treatment for spondyloptosis is very rare. A 15-year-old girl with L5-S1 spondyloptosis was admitted with severe low back pain. There was no history of trauma. The patient underwent L5 laminectomy, L5-S1 discectomy, resection of sacral dome, reduction, L3-L4-L5-S1 pedicular screw fixation, and interbody-posterolateral fusion through the posterior approach. The reduction was maintained with bilateral L5-S1 discectomy, resection of the sacral dome, and transpedicular instrumentation from L3 to S1. In this particular case, one-staged approach was adequate for the treatment of L5-S1 spondyloptosis. One-staged surgery using the posterior approach may be adequate for the treatment of L5-S1 spondyloptosis while avoiding the risks inherent in anterior approaches.