Effect of clival bone growth on the localization of the abducens nerve at the petroclival region: a postmortem anatomical study.

PURPOSE: To investigate the effect of the clival bone pattern on the abducens nerve (AN) localization in the petroclival region between the Pediatric and Adult Groups. METHODS: This study used 12 pediatric and 17 adult heads obtained from the autopsy. The length and width of the clivus and the length of the petrosphenoidal ligaments (PSLs) were measured. The ratio of the length and width of the clivus was accepted as the clival index (CI). The localization of the AN at the petroclival region below the PSL, classified as lateral and medial, were recorded. RESULTS: The average length of the clivus was 26.92 ± 2.88 mm in the Pediatric Group, and 40.66 ± 4.17 mm in the Adult Group (p < 0.001). The average width of the clivus was 22.35 ± 2.88 mm in the Pediatric Group, and 29.96 ± 3.86 mm in the Adult Group (p < 0.001). The average value of the CI was 1.20 in the Pediatric Group and 1.36 in the Adult Group (p = 0.003). The length of the PSL was 7.0 ± 1.47 mm in the Pediatric Group and 11.05 ± 2.95 mm in the Adult Group (p < 0.001). The nerve was located below the medial side of the PSL in the Pediatric Group and below the lateral side in the Adult Group (p = 0.002). CONCLUSIONS: The petrous apex localization of the AN in adults compared with pediatric subjects could be related to the increased growth in the length of the clivus than its width.

Comparison of Thalamus Volume on Magnetic Resonance and Cadaveric Section Images.

AIM: To measure and to compare the volume of thalamus using magnetic resonance imaging (MRI) and the anatomical sections. MATERIAL AND METHODS: In this study, 13 brain specimens were used. First, the images were taken in 3 mm sections on MRI, the thickness of the thalamus was measured. Subsequently, 4 mm coronal sections were prepared using a microtome. The thalamic volumes calculated from cadaveric specimens were compared with the measurements obtained using MRI. RESULTS: On MRI, the mean thalamic volumes on the right and left hemispheres were found to be 5843.4 ± 361.6 mm3 and 5377.0 ± 666.2 mm3 respectively. The mean volumes of the cadaveric sections were 5610.8 ± 401.3 mm3 on the right side and 5618.5 ± 604.1 mm3 on the left hemisphere. No statistically significant difference was found between the volume calculated from MRI and that obtained from the cadaveric section (p < 0.05). CONCLUSION: This study shows a correlation between measurement of thalamus volume based on MRI and those calculated from anatomical sections. Our findings support the reliability of DBS procedures using MRI and stereotactic method.

Research on the Effects of Levetiracetam in Spinal Cord Injury Model in Rats: An Experimental Study.

Purpose: Despite advances in spinal biomechanic research, surgical techniques, and rehabilitation processes, no significant improvement has been identified in the treatment of spinal cord injury (SCI) and neurological recovery. Aim of the Study: This study was designed to investigate the potential therapeutic effects of methylprednisolone and levetiracetam on SCI. Materials and Methods: In this study, 42 male Wistar Albino rats, each weighing 300-350 g, were separated into three main groups: control group, acute and subacute stage groups. With the exception of the control group, a T7-8 dorsal laminectomy was performed on the spinal column of the rats. A temporary vascular aneurysm clip was then applied to the spinal cord for 1 min to create SCI and methylprednisolone or levetiracetam was administered intraperitoneally to all except the control and SHAM control groups. The damaged spinal cord was removed for histopathological and biochemical examinations. Results: Both pharmacological agents were determined to have improved the histopathological architecture in damaged neural tissues during the acute period of SCI, but could not sustain this activity in the subacute period. Neither pharmacological agent affected the biochemical data in the acute nor subacute stages. Conclusions: Both pharmacological agents showed histopathological healing effects in injured tissues during the acute phase of SCI in this rat model but these effects could not be sustained in the subacute period. No effect on biochemical data was seen in either the acute or subacute period. There is a need for further advanced studies to determine the effects of levetiracetam on the healing processes in SCI.

Sonoelastographic evaluation of the sciatic nerve in patients with unilateral lumbar disc herniation.

OBJECTIVE: The aim of this study was to compare strain elastography (SE) and shear wave elastography (SWE) findings of the sciatic nerve in patients with unilateral lumbar disc herniation (LDH) and healthy control subjects. MATERIALS AND METHODS: The study group included patients with complaints of unilateral sciatica for 3-12 months, with foraminal stenosis due to one level of LDH (L4-L5 or L5-S1). An age- and gender-matched control group was formed of healthy subjects. Evaluations were performed on both the axial and longitudinal planes from the bilateral gluteal region using a 5-9 MHz multifrequency convex probe. RESULTS: There were 40 patients (20 male, 20 female) with a mean age of 43.1 ± 12.7 years in the study group, and 40 healthy subjects (22 male, 18 female) with a mean age of 42.9 ± 10.7 years in the control group (p > 0.05). The sciatic nerve stiffness assessed on both the axial (12.3 ± 3.7 kPA) and longitudinal (14.3 ± 3.8 kPA) planes of the involved side was significantly higher than non-involved side (axial: 6.8 ± 2.1 and longitudinal: 8.3 ± 2.3 kPA) in the patient group (p < 0.001). CONCLUSIONS: Patients with unilateral LDH have increased stiffness of the sciatic nerve compared to healthy control subjects. Although the findings in this preliminary study show that shear wave elastography can detect a change in sciatic nerve stiffness in patients with unilateral LDH, larger studies are required to determine the clinical utility of this technique.

Analysis of biochemical laboratory values to determine etiology and prognosis in patients with subarachnoid hemorrhage: a clinical study.

OBJECTIVES: The aim of this study was to establish prognostic and predictive markers in patients with subarachnoid hemorrhage (SAH) using simple laboratory methods. METHODS: A retrospective examination was made of patients with SAH diagnosed secondary to isolated head trauma, isolated anterior communicating artery aneurysm rupture, and angiography-negative SAH. Age, gender, Glasgow Coma Scale (GCS) scores, and Fisher's grade scores, Glasgow Outcome Scale (GOS) scores, leukocyte count, neutrophil count, lymphocyte count, platelet count, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio results (PLR) were evaluated. RESULTS: NLR and PLR values, which were similar in patients with spontaneous SAH, were significantly high in patients with traumatic SAH. NLR and PLR values could be 80% sensitive and 75% specific for distinguishing traumatic SAH from spontaneous SAH. Eosinophil count was lower in patients with angiography-negative SAH and patients with aneurysmal SAH than in patients with traumatic SAH. Initially measured GCS score, Fisher's grade score, eosinophil, neutrophil and lymphocyte counts could be prognostic in all patients with SAH. Moreover, it was concluded that the initially measured number of eosinophils might be directly related to patient prognosis. The eosinophil count was generally found to be high in traumatic SAH patients and it was observed that this parameter could be predictive for these patients. Lymphocyte count and NLR values could be prognostic markers in patients with angiography-negative SAH. CONCLUSION: NLR, PLR and eosinophil count values could be predictive for etiological factors (traumatic SAH or spontaneous SAH) of patients who were admitted unconscious to the emergency room with SAH detected on radiological imaging.

An Evaluation of the Quality of Sleep Before and After Surgical Treatment of Patients with Cervical Disc Herniation.

OBJECTIVE: It has been reported in recent studies that 50-80% of patients with cervical disc hernia have concomitant sleep disorders. The aim of this study was to evaluate the quality of sleep before and after surgical treatment in patients with cervical disc hernia and to assess the effects on treatment. METHODS: The study included 32 patients performed discectomy and fusion with an intervertebral cage through the right anterior cervical approach. Oswestry Disability Index (ODI), Visual Analog Scale (VAS) and Pittsburgh Sleep Quality Index (PSQI) were applied to all patients preoperatively and at one month postoperatively. RESULTS: The postoperative PSQI total points and all the PSQI subscale points, the ODI and VAS scores were significantly reduced compared to the preoperative values. A positive correlation was determined between the preoperative ODI points and the PSQI total points and sleep duration, sleep latency and daytime functional loss subscale points. A positive correlation was also found between preoperative ODI points and VAS points. A positive correlation was determined between the preoperative VAS points and and the PSQI total points and sleep duration, and sleep latency subscale points. A negative correlation was determined between the postoperative ODI and the daytime functional loss subscale points. CONCLUSION: The results of the study showed that in patients with cervical disc hernia, sleep quality and daytime functionality were negatively affected by severity of pain that limited daily activities. Bringing the pain under control with surgical treatment was observed to increase sleep quality. It can be concluded that when planning treatment for these patients, it should be taken into consideration that there could be a sleep disorder in addition to the complaints and symptoms such as pain, hypoestesia and loss of strength.

Evaluation of posterior clinoid process pneumatization by multidetector computed tomography.

In the present study, we investigated the types and ratio of posterior clinoid process (PCP) pneumatization in paranasal sinus multidetector computed tomography (MDCT). Paranasal MDCT images of 541 subjects (227 males, 314 females), between 15 and 65 years old, were included into the study. Pneumatization of anterior clinoid process and pneumatization types (I, II, or III) were evaluated in the males and females. PCP pneumatization was detected in 20.7 % of the males and 11.5 % of the females. Right, left, and bilateral PCP pneumatizations were detected in 7.9, 5.7, and 7.0 % of the males and 2.9, 3.2, and 4.5 % of the females, respectively. PCP pneumatization of the males is significantly higher than the females. The most detected type of pneumatization was type I (61.2 %) for all groups. In right, left, and bilateral pneumatizations separately, type I pneumatization was the most detected pneumatization type with the ratio of the 70.4, 65.2, and 50.0 %, respectively. In males, type I (61.7 %), and similarly in females, type I (60.6 %) pneumatization were detected more. Type II and type III pneumatizations were detected in decreasing order in both groups. In younger subjects, pneumatization of posterior clinoid process was found as higher, and in older subjects, PCP pneumatization was found as lower. Sclerosis process related to the aging may be responsible for the lower pneumatization ratios in older subjects. Structure of the surrounding regions of PCP is important for surgical procedures related to cavernous sinus, basilar apex aneurysms, and mass lesions. Preoperative radiological examinations are useful for operative planning. Any anomalies to PCP can cause unnecessary injury to the neurovascular complex structure around the cavernous sinus or postclinoidectomy CSF fistulas. Posterior clinoidectomies should be avoided in patients with type III PCP pneumatization to prevent CSF fistulas.

Investigation of the calcification at the petroclival region through Multi-slice Computed Tomography of the skull base.

OBJECTIVES: The aim of this paper was a retrospective investigation of calcification at the petroclival region using Multi-slice Computed Tomography (MSCT). METHODS: One hundred thirty skull bases were reviewed. The images were acquired with a 64 slice CT (MSCT). At first images were taken at the axial plane; and then coronal and sagittal reconstructions of raw data were performed. Later investigations were carried out on these 3-dimensional images (3-D imaging). Petrosphenoidal ligament (PSL) (Gruber's ligament) and posterior petroclinoid ligament (PPCL) calcifications were evaluated as "none, partial or complete calcification" for the right and left sides. RESULTS: In the right PSL, there were partial calcifications in 9.8% and complete calcifications in 2.3%. Calcification ratio was 9.8% partial and 2.9% complete in the left PSL. In the right side, there were 26.6% partial and 5.2% complete calcifications of PPCL. In the left side, there were 29.5% partial and 4.6% complete PPCL calcifications. PPCL calcification was detected more in males compared to females in the right and left sides. In older patients, left PSL; right and left PPCL calcification were detected more. CONCLUSION: PPCL calcifications cannot be differentiated from PSL calcifications in MSCT slices. The distinction can be easily done in 3-D views. The presence of ossified ligaments may make surgeries in this region difficult, and special care has to be taken to avoid injuries to structures which pass under these ossified ligaments. Particularly in elderly patients, the appropriate surgical instrument for the PSL calcifications should be prepared preoperatively. If PSL is calcified, 6th cranial nerve palsy may not occur even though increased intracranial pressure syndrome is present. Whereas, in lateral trans-tentorial herniations, 3rd cranial nerve palsy occurs in earlier periods when PSL is calcified. Moreover, in subtemporal and transtentorial petrosal approaches, knowing the PSL calcification preoperatively is important to avoid damaging the 6th cranial nerve during surgery.

The Presence of Clival Foramen Through Multidetector Computed Tomography of the Skull Base.

OBJECTIVES: Technological advancements in the diagnostic radiology recently permitted reviewing the normal anatomy through multidetector computed tomography (MDCT) imagination. The aim of this paper is retrospectively investigation of the clival foramen and canal through MDCT. MATERIALS AND METHODS: One hundred eighty-six MDCT scans were reviewed. First, images were taken at axial plane, and then coronal and sagittal reconstructions of raw data were performed. Later investigations were carried out on these three-dimensional images (3-D imaging). The images were evaluated as clival foramen "present" or "absent." RESULTS: In our 186 patients, evaluation of MDCT showed that clival foramen was absent in 66.7% (n = 124) of patients. Only 33.3% (n = 62) of patients had a clival foramen. In 3-D images, clival canal and clival foramen were shown more clearly compared with the MDCT. CONCLUSIONS: Knowledge of the clival canal might be useful in patients of questionable clival fracture or during neurosurgical operations in this region. During life the canal contained a vein connecting the basilar plexus with the venous plexus of the vertebral canal, and inferior petrosal sinuses. Before the surgical interventions in the clival region, the presence of the clival canal and foramen should also be known due to its vascular contents. By multidetector computed tomography and 3-D images, clival canal and foramen may be viewed preoperatively.

Spinal gas accumulation causing lumbar discogenic disease: a case report.

Vacuum disc phenomenon is seen frequently with degenerative disc disease and is characterized by the collection of gas in the disc space. Although the accumulation of gas within the disc space does not have clinical significance, symptoms may develop when occurring within the spinal canal. We present a 60-year-old female patient with low back and left leg pain occurring for 3 months before admission to our clinic. Straight leg raise test was 50 degrees in the left leg. Magnetic resonance imaging showed a narrowing of the L5-S1 disc space with vacuum disc phenomenon and hypointense cystic mass in T1 and T2-weighted images. The decision for surgery was made and left L5-S1 hemilaminectomy and foraminotomy was performed. The cyst wall was adherent to the root and dura mater and was partially excised. The patient was pain-free on the first postoperative day. In cases of gas accumulation in the spinal canal, discogenic pain may occur. Surgical therapy is still an acceptable method for the treatment of vacuum disc phenomenon and accumulation of gas within the spinal canal.

Poloxamer-188 and citicoline provide neuronal membrane integrity and protect membrane stability in cortical spreading depression.

Under pathological conditions such as brain trauma, subarachnoid hemorrhage and stroke, cortical spreading depression (CSD) or peri-infarct depolarizations contribute to brain damage in animal models of neurological disorders as well as in human neurological diseases. CSD causes transient megachannel opening on the neuronal membrane, which may compromise neuronal survival under pathological conditions. Poloxamer-188 (P-188) and citicoline are neuroprotectants with membrane sealing properties. The aim of this study is to investigate the effect of P-188 and citicoline on the neuronal megachannel opening induced by CSD in the mouse brain. We have monitored megachannel opening with propidium iodide, a membrane impermeable fluorescent dye and, demonstrate that P-188 and citicoline strikingly decreased CSD-induced neuronal PI influx in cortex and hippocampal dentate gyrus. Therefore, these agents may be providing neuroprotection by blocking megachannel opening, which may be related to their membrane sealing action and warrant further investigation for treatment of traumatic brain injury and ischemic stroke.

Importance of the perforating arteries in the proximal part of the PICA for surgical approaches to the brain stem and fourth ventricle--an anatomical study.

OBJECTIVE: The purpose of this study is to examine the perforating arteries (PAs) in the proximal part of the posterior inferior cerebellar artery (PICA) for surgical approaches to the brain stem and fourth ventricle, and to stress their importance in microsurgical procedures. METHODS: Twenty-six adult cadaver obtained from routine autopsies were used. During the examination, the PAs and the segmental structure of the proximal part of the PICAs and their relation to the neighbouring anatomical structures were demonstrated. RESULTS: We classified the PICAs into 4 types on the basis of the distance of the middle point of the width of the caudal loop to the midline, and their presence or absence as Group A (symmetrical, anterior medullary type: 26.9%), Group B (lateral medullary type: 15.4%), Group C (asymmetrical type: 38.5%), and Group D (unilateral type: 19.2%). The number of the PAs in the tonsillomedullary segment and the caudal loop was higher than those originating from the other segments. CONCLUSIONS: Approaches to the medial or lateral of the PICA should be made in a way that protects the PAs (avoiding retraction of the PICA). Otherwise the PAs will be damaged and as a result brain stem ischaemia may occur, which can have serious clinical outcomes.