No abstract

The veins of the brain have no muscular tissue in their thin walls and possess no valves. They emerge from the brain and lie in the subarachnoid space. They pierce the arachnoid mater and the meningeal layer of the dura and drain into the cranial venous sinuses. The cerebral venous system can be divided into a superficial and a deep system. The superficial system comprises sagittal sinuses and cortical veins, which drain superficial surfaces of both cerebral hemispheres. The deep system consists of the lateral sinus, straight sinus and sigmoid sinus along with draining deeper cortical veins. Both of these systems mostly drain into internal jugular veins. Generally, venous blood drains into the nearest venous sinus or, in the case of blood draining from the deepest structures, into deep veins. The superficial cerebral veins are interlinked with anastomotic veins of Trolard and Labbé. Thus, the superolateral surface of the hemisphere drains into the superior sagittal sinus while the posteroinferior aspect drains into the transverse sinus. The veins of the posterior fossa are variable in course, and angiographic diagnosis of their occlusion is difficult. The entire deep venous system is drained by internal cerebral and basal veins, which join to form the great vein of Galen that drains into the straight sinus. Though variation in the superficial cerebral venous system is a rule, anatomic configuration of the deep venous system can be used as anatomic landmarks. Since thrombosis or surgical sacrifice of the cerebral veins may lead to venous infarction with serious complications, angiographic and surgical anatomy of the venous system should be seriously investigated for each individual patient.

The DN represents an important anatomic structure in surgical interventions involving the posterior fossa, particularly in the elderly because of the common occurrence of atrophy-related problems in this age group. Functionally and anatomically, the DN is closely related to the superior and middle cerebellar peduncles. The inferior cerebellar peduncle poses positional risks because it follows an anterior and superior course relative to the DN. The telovelar approach is a safer procedure for interventions involving the pathological lesions of the fourth ventricle floor.

This approach causes less tissue damage; provides control of the surgical area in spheno-orbital tumors invading the fissure and foramen by changing the orientation of the microscope toward the orbit, OA, SOF, CS, and middle fossa; and expands the indication criteria for lateral orbitotomy surgery. This approach, therefore, represents an alternative surgical method for excising complicated tumors in these regions.

This study, for the first time, provides experimental semiquantitative data to compare the angiogenic potentials of embolized and gamma knife-treated AVM tissues. Embolization may increase angiogenic activity, and gamma knife radiosurgery may decrease it when compared with activity in previously untreated AVMs. These data can be useful to understand why recurrence of AVMs after angiographically demonstrated endovascular occlusion is common but after gamma knife occlusion is rare.

Atretic cephaloceles present as nodular extrusions on the parietal and occipital regions. Concomitant CNS anomalies, which impair the clinical outcomes, are more common in patients with parietal ACs. Observation-only approach is enough in patients with asymptomatic ACs. However, life-long follow-ups are required, because of recurrence after the surgery.

Ventriculoperitoneal shunt systems that are used in the treatment of normal pressure hydrocephalus are often associated with drainage problems. Adjustable shunt systems can prevent or treat these problems, but they may be expensive. The aim of our study is to compare the complications and total cost of several shunt systems.Patients with normal pressure hydrocephalus who underwent ventriculoperitoneal shunting between 2011 and 2016 were included in the study. The study involves patient consent and the informed consent was given. Complications and the average cost per person were compared between patients with adjustable and nonadjustable shunts. Shunt prices, surgical complications, and revision costs were taken into account to calculate the average cost.Of the 110 patients who were evaluated, 80 had a nonadjustable shunt and 30 had an adjustable shunt. In the group with adjustable shunts, the rates of subdural effusion and hematoma were 19.73% and 3.29%, respectively. In the group with nonadjustable shunts, these rates were 22.75% and 13.75%, respectively. One patient in the adjustable group underwent surgery for subdural hematoma, while 8 patients in the nonadjustable group underwent the same surgery. Ten patients required surgical intervention for subdural effusion and existing shunt systems in these patients were replaced by an adjustable shunt system. When these additional costs were factored into the analysis, the difference in cost between the shunt systems was reduced from 600 United States dollars (USD) to 111 USD.When the complications and additional costs that arise during surgical treatment of normal pressure hydrocephalus were considered, the price difference between adjustable and nonadjustable shunt systems was estimated to be much lower.

OBJECT Due to lack of construct stability of the current anterior cervical approaches, supplemental posterior cervical approaches are frequently employed. The use of an anterior-only approach with anterior transpedicular screws (ATPSs) has been proposed as a means of providing 3-column fixation. This study was designed to investigate the feasibility of anterior transpedicular screw (ATPS) fixation of cervical spine, to obtain the morphological measurements for technical prerequisites, and to evaluate the accuracy of the ATPS using fluoroscopy. METHODS The study included both radiological and anatomical investigations. The radiological investigations were based on data from cervical spine CT scans performed in 65 patients. Technical prerequisites of ATPS were calculated using OsiriX for Mac OS. In the anatomical part of the study, 30 pedicles (C3–7) from 6 formalin-preserved cadavers were manually instrumented. Measurements obtained included pedicle width (PW), pedicle height (PH), pedicle transverse angle (PTA), distance of the entry point from the midline (DEPM), and distance of the entry point from the superior endplate (DEPSEP). The authors also analyzed screw position in the manually instrumented vertebrae. RESULTS The mean PW and PH values showed a tendency to increase from C-3 to C-7 in both males and females. The means were significantly larger for both PW and PH in males than in females at all levels (p = 0.001). The overall mean PTA value was significantly lower at C-7 (p < 0.0001). The mean value for the distance of entry point from the midline (DEPM) represented a point at the contralateral side of the pedicle for every level except C-7. The mean DEPSEP values showed significant differences between all levels (p < 0.0001). Seven of the 30 screws were identified as breaching the pedicle (23.3%); these screw malplacements were seen at C-3 (3 screws), C-4 (2 screws), and C-5 (2 screws). CONCLUSIONS The morphological measurements of this study demonstrated that ATPS fixation is feasible in selected cases. They indicate that ATPS insertion using a fluoroscopy-assisted pedicle axis view is safe at the C-6 and C-7 levels, but the results at the other levels did not prove the safety of this technique.