Microanatomical characteristics of the petrosphenoidal ligament of Gruber.

AIM: The petrosphenoidal ligament (PSL, or Gruber's ligament) is located between the petrous apex (PA) and posterior clinoid process (PCP). Details of its anatomy are conflicting in the few studies that exist in the literature. We performed this study to describe in detail the microanatomical characteristics of Gruber's ligament. MATERIAL AND METHODS: 20 human cadaveric heads (40 specimens) were used to make morphometric measurements and qualitative evaluations of the microanatomy of the petrosphenoidal ligament. RESULTS: The anatomy of the PSL was predominately butterfly (78%) in shape, with the remaining being triangular (22%). The structure of the PSL was complete in 52% of cases and incomplete (fragmented or hypoplastic) in 38%. A second, smaller ligament was seen in 10% of cases. Mean length of the PSL was 13.4+/-3.2 mm, mean width was 6.1+/-3.2 mm at the PCP and 4.2+/-1.6 mm at the petrous apex. Butterfly-shaped ligaments were narrowest in the middle (mean 2.0+/-0.9 mm), while triangle-shaped ligaments were narrowest (mean 2.8+/-2.3 mm) at its end, at its insertion on the PA or PCP. CONCLUSION: The PSL (Gruber's ligament) is an important structure in the petroclival region. In this study, microanatomical characteristics were described in detail, along with new descriptions of its shape.

Microanatomical study of the intracranial abducens nerve: clinical interest and surgical perspective.

AIM: The microanatomy of the abducens nerve (AN) is important for clinical reasons and surgical approaches as it is located in the petroclival region. The incidence of branching and duplication of the abducens nerve are unknown and mechanisms relating to paralysis of the nerve in indirect conditions are yet to be clarified. MATERIAL AND METHODS: Microanatomical details (anatomical observations and morphometric measurements) of the AN were obtained from 20 cadaveric skull bases (40 specimens). RESULTS: 55% of the intracranial abducens nerves had branching, with type 2 and 3 branching occurring in 10%. The nerve coursed below the petrosphenoidal ligament in all but one, and was located at the lateral third below the ligament in 82.5% of the specimens. The mean AN diameter was 1.3±0.2 mm, and the mean diameter of the dural entrance pore was 1.8±0.3 mm, the right being significantly larger than the left. The mean distance of the AN from the posterior clinoid process was 8.4±2.5 mm and from the petrous apex 3.6±2.1 mm. CONCLUSION: Branching of the AN was present in a significant number of specimens; the branching pattern at the cavernous segment may be called "pseudobranching". The AN is at risk for paresis in indirect conditions because of its angles and fixations on its course.

Magnesium Acetyl Taurate Prevents Tissue Damage and Deterioration of Prosocial Behavior Related with Vasopressin Levels in Traumatic Brain Injured Rats.

AIM: To investigate the effects of different magnesium forms on tissue damage, cognitive and emotional behavioural impairment after mild traumatic brain injury (TBI). MATERIAL AND METHODS: Rats were divided into 5 groups (control, trauma, magnesium sulphate, magnesium citrate, magnesium acetyl taurate) and following head trauma, empathy-like behaviour, anxiety-like behaviour (elevated plus maze and open field tests), and depression (forced swim test) were measured. The rats were then sacrificed 12 days later. Oxytocin, vasopressin and receptors levels in the amygdala and prefrontal cortex regions were measured. Histopathological damage (with haematoxylin-eosin staining) and apoptosis (with caspase-3 immunohistochemistry) was evaluated. RESULTS: Following head trauma, anxiety-like behaviour and depression tests did not change; empathy-like behaviour deteriorated on the 3rd day and improved gradually on the 6th and 12th days. Oxytocin, vasopressin and vasopressin v1b receptor levels decreased in the amygdala; morphological damage and apoptosis were significant. Magnesium acetyl taurate effectively ameliorated histopathological deteriorations and improved vasopressin and v1b receptor levels in the amygdala. Transient deterioration of empathy-like behaviour was impeded only in magnesium taurate treatment. CONCLUSION: Magnesium acetyl taurate can be a promising candidate agent to prevent structural and functional damage in traumatic brain injury.

Misdiagnosis due to the hook effect in prolactin assay.

OBJECTIVES: To describe a patient who was misdiagnosed as having a nonfunctional pituitary tumor due to the hook effect on prolactin measurements. CLINICAL PRESENTATION AND INTERVENTION: A 45-year-old female was admitted with visual disturbances, panhypopituitarism and central diabetes insipidus due to pituitary tumor recurrence. She had been operated 4 times earlier and received cranial irradiation for a suspected nonfunctional pituitary adenoma. Serum prolactin was moderately elevated (164.5 ng/ml), but increased markedly after 1:100 dilution to 14,640 ng/ml. Diagnosis of a giant macroprolactinoma was made and cabergoline was started. Prolactin level normalized and a mild shrinkage of the tumor was achieved after 12 months of therapy. CONCLUSION: The hook effect must be kept in mind while evaluating a giant pituitary adenoma with moderately elevated prolactin levels. This way unnecessary surgical procedures or irradiation may be avoided.

Surgical treatment of 13 pediatric patients with Dandy-Walker syndrome.

We present our experience with the treatment of 13 patients with Dandy-Walker syndrome. The common presenting symptom and associated central nervous system anomaly were enlargement of head and occipital encephalocele, respectively. Eleven out of 13 patients were treated surgically after stabilization of systemic medical status. Two patients could not be operated because of poor medical condition. In 6 patients with an opened passage between posterior fossa cyst and lateral ventricle, cystoperitoneal shunt system with medium pressure valve was the treatment of choice. In 5 patients with no relation between cyst and ventricle, cystoperitoneal and ventriculoperitoneal shunting with 'Y' connectors were applied separately. Another patient with a shunt infection was treated by shunt system renewal combined with parenteral antibiotics. One patient died 7 months after the operation due to recurrent meningitis.

Effects of Quercetin and Mannitol on Erythropoietin Levels in Rats Following Acute Severe Traumatic Brain Injury.

OBJECTIVE: The aim of this study to investigate the normal values of erythropoietin (EPO) and neuroprotective effects of quercetin and mannitol on EPO and hematocrit levels after acute severe traumatic brain injury (TBI) in rat model. METHODS: A weight-drop impact acceleration model of TBI was used on 40 male Wistar rats. The animals were divided into sham (group I), TBI (group II), TBI+quercetin (50 mg/kg intravenously) (group III), and TBI+mannitol (1 mg/kg intravenously) (group IV) groups. The malondialdehyde, glutathione peroxidase, catalase, EPO, and hematocrit levels were measured 1 and 4 hour after injury. Two-way repeated measures analysis of variance and Tukey's test were used for statistical analysis. RESULTS: The malondialdehyde levels decreased significantly after administration of quercetin and mannitol compared with those in group II. Catalase and glutathione peroxidase levels increased significantly in groups III and IV. Serum EPO levels decreased significantly after mannitol but not after quercetin administration. Serum hematocrit levels did not change significantly after quercetin and mannitol administration 1 hour after trauma. However, mannitol administration decreased serum hematocrit levels significantly after 4 hour. CONCLUSION: This study suggests that quercetin may be a good alternative treatment for TBI, as it did not decrease the EPO levels.

Asymmetric Posterior Thoracolumbar Fixation following a Posterolateral Transpedicular Approach for Unilateral Vertebral Disease.

The present study aimed to evaluate the clinical outcomes of patients who underwent asymmetrical posterior screw fixation for the treatment of unilateral posterior vertebral pathological entities. The study included 21 patients with a spinal tumor who underwent asymmetrical posterior spinal fusion surgery between April 2009 and March 2012. The American Spinal Injury Association (ASIA) motor score visual analog scale (VAS) score were used as the outcome measure at admission and follow-up. Among the 21 patients, 12 were male and 9 were female, and mean age was 50.71 (range, 24-78) years. Mean follow-up was 16.04 (range, 4-47) months. Postoperatively, neurological findings did not deteriorate in any of the patients. Among the ASIA grade C and D patients, eight (38%) of them exhibited clinical stability or recovery to ASIA E, whereas none of the ASIA B patients scores changed postoperatively. Perioperative complications were noted in six patients (28%). Spinal stability and fusion were achieved in 18 (85%) patients. The surgical asymmetrical fixation technique described reduced the duration of surgery, and the patients required less dissection of paraspinal muscles than bilateral symmetrical fixation. Asymmetrical fixation provides good stabilization for unilateral thoracolumbar vertebral pathological entities, and facilitates rapid rehabilitation of such patients, who are often elderly with comorbidities.

An anatomical study of the C-2 pedicle.

OBJECT: The C-2 pedicle plays an important role regarding screw purchase for spinal fixation. The aim of this study was to measure the C-2 pedicle-related linear and angular parameters. METHODS: Seven parameters in 160 C-2 pedicles (80 dry vertebrae) were measured using a Vernier caliper (accurate to 0.1 mm) and goniometer. The Student t-test was used to determine statistical significance. The authors found that the C-2 isthmus (pars interarticularis) and the C-2 pedicle are distinct structures. The C-2 isthmus covers the pedicle. The isthmus is present between the superior and inferior articular processes, and the pedicle is the structure beneath the C-2 isthmus. It connects the lateral mass-inferior articular process to the body of the axis. The heights of the right and the left C-2 pediculoisthmic components (PICs) were 10.3 +/- 1.6 and 9.9 +/- 1.5 mm, respectively. The posterior part of the superior aspect of the PIC was wider than the anterior portion. The widths of the posterosuperior aspect of the PIC were 11.1 +/- 2 and 11 +/- 1.7 mm on the right and left sides, whereas the widths of the anterosuperior aspect of the PIC were 7.9 +/- 1.7 and 8.5 +/- 1.6 mm, respectively. The inferior widths of this component were 6.0 +/- 1.5 and 5.5 +/- 1.3 mm on the right and left side, respectively. The lengths of the component were 28.8 +/- 2.9 mm on the right and 28.8 +/- 3.4 mm on the left side. The PIC exhibits a lateral-to-medial and an inferior-to-superior angle. Its axial angles were 28.4 +/- 2.5 and 28.6 +/- 2.2 degrees on the right and left sides, respectively; its sagittal angles were 18.8 +/- 2.1 and 18.8 +/- 1.7 degrees, respectively. CONCLUSIONS: The C-2 pedicle can be seen in the inferior aspect of the vertebra, and it connects posterior vertebral elements (that is, the lateral mass and inferior articular process) to the axial body. The isthmus drapes the pedicle. The authors suggest that this be termed "the pediculoisthmic component."

Treatment of aneurysms arising from the proximal (A1) segment of the anterior cerebral artery.

The aim of our study was to report a series of 15 consecutive patients with aneurysms of the proximal segment (A1) of the anterior cerebral artery. In 15 patients with diagnosed A1 aneurysms, representing 2.1% of 720 aneurysm patients treated at a University Clinical Center between October 1999 and August 2012, clinical presentation, neuroradiological findings, surgical treatment methods and outcome were retrospectively analyzed. Mean patient age was 53.06 (range 32 to 75) years. Ten saccular aneurysms were treated with micro neurosurgical approach via standard pterional craniotomy, four fusiform aneurysms with coiling, and one fusiform aneurysm with stent. No patients died during the operation. The mean follow-up period was 32 months (range 5 months to 7 years). Clinical outcomes revealed good recovery in all patients. Despite the general opinion that A1 aneurysms are benign lesions, an increasing number of reports have demonstrated their potential complications. To date, due to the rarity of A1 aneurysms, only a few consecutive series have been reported. Conduct of multicenter studies are required in order to understand clinical features of A1 aneurysms and devise a proper treatment plan.

A rare embryologic variation: anterior communicating artery aneurysm associated with carotid-anterior cerebral artery anastomosis or infraoptic course of the anterior cerebral artery.

Aneurysms of the complex of the anterior cerebral artery are frequently associated with anatomic variations of the circle of Willis. We describe a case of aneurysmal rupture of the anterior communicating artery, a variant of the anterior cerebral artery. The aneurysm appeared to be situated on this vessel proximal to the infered site of the AcoA. Surgery was performed at the 6th day after hemorrhage. The anterior communicating artery aneurysm was clipped. The post operative course was unventful, with complete recovery. In our case, an extremely rare variation of the proximal tract of the anterior cerebral artery, i.e. an infraoptic course of the proximal precommunicating tract under the optic nerve, with the distal A1 tract anterior to the chiasm and positioned between the optic nerves, is presented.