Expression of miRNA-451 and miRNA-885 in Meningiomas.

BACKGROUND/AIM: Meningiomas are one of the most common intracranial tumors, accounting for 30% of the tumors of the central nervous system. MicroRNAs (miRNAs) are noncoding RNAs containing approximately 18-22 nucleotides that regulate gene expression by interfering with transcription or inhibiting translation. Recent studies have reported that miRNAs could provide information about the molecular pathogenesis of several types of tumors. This study aimed to examine the expression levels of miRNA-885 and -451 and to determine their potential roles as biomarkers in meningioma. MATERIALS AND METHODS: In total, 29 patients with meningioma (9 males and 20 females) were included in this study. The expression levels of miRNA were determined using real-time polymerase chain reaction. In addition, receiver operating characteristic curve analysis was used to analyze the predictive potential of miRNAs. RESULTS: Our results indicated a significant increase in miRNA-451 expression levels (p=0.003); however, there was no significant change in miRNA-885 expression levels (p=0.139) in patients with meningioma compared with the control group. Moreover, miRNA-885 and miRNA-451 expression levels did not differ significantly based on the histopathological grade of meningioma. CONCLUSION: miRNA-451 may be a novel potential marker for the diagnosis and prognosis, and a target for meningioma treatment.

Investigation of Neuroprotective Effect of Shilajit Extract in Experimental Head Trauma Model Created in Rats.

AIM: To investigate the neuroprotective effect of shilajit extract in experimental head trauma. MATERIAL AND METHODS: Three groups of 33 Sprague Dawley Albino strain male rats were included in the study. Group 1 (n=11): trauma but not treated. Group 2 (n=11): trauma and treated with 0.5 mL / rat saline Group 3 (n=11): 150 mg / kg shilajit extract was administered intraperitoneally in the treatment of trauma. Following the head trauma, the indicated treatments were applied to the 2nd and 3rd groups at the first, twenty-four and forty-eighth hours. Brain tissues and blood samples were taken after the control animals were sacrificed at the 72nd hour in all groups after trauma. Sections prepared from cerebral cortex and ca1 region were examined with hematoxylin eosin and luxol fast blue staining. Total antioxidant capacity, total oxidant capacity and oxidative stress index were measured from blood samples taken after routine procedures. RESULTS: The number of red neurons and the severity of edema were significantly higher in both the cerebral cortex and the ca1 region in the group treated with trauma only and in the group administered saline after trauma compared to the group that received shilajit extract after trauma. The total antioxidant capacity increased significantly in blood samples taken only from the group treated with trauma and saline in post-trauma treatment compared to the group given post-traumatic shilajit extract, while shilajit extract given due to traumatic brain injury significantly decreased the total oxidant capacity and oxidative stress index values compared to the other groups. CONCLUSION: Shilajit extract has been shown to have a neuroprotective effect in the treatment of acute traumatic brain injury. Our study showed that shilajit may be a useful option in the treatment of secondary brain injury, in humans.

Long-term follow-up results of surgically treated patients with foraminal and far lateral disc herniations.

PURPOSE: Foraminal and far lateral disc herniations are rarer cause of nerve root compression. There are reports regarding the outcome, however long-term follow-up results of surgically treated patients are few. The purpose of this retrospective study is to analyze the clinical characteristics and long-term surgical outcomes of the foraminal and far lateral disc herniations. MATERIALS AND METHODS: The 114 patients who underwent an operation for foraminal and far lateral disc herniaitions were reviewed. Visual analogue scale of back and leg pain, the ocurrence of motor deficit and sensory dysesthesia before and after operations were used to compare the results of early and long-term outcome. RESULTS: A total of 114 telephone interviews were conducted. The mean follow up was 134 months. Complete relief of symptoms were reported by 77 patients (67.1%). The average VAS of radicular leg pain was 7.5 Post-operatively the average VAS of radicular pain decreased to 2.2. Preoperatively, 9 patients (7.6%) had motor deficit and 17 (14.4%) patients had sensory dysesthesia. Post-operatively 9 (100%) of the patients showed motor, and 12 (70.6%) of the patients showed sensory improvement. In 17 patients with hypoesthesia the complaints continued during 2 weeks to 6 months. They were given gabapentin as medical treatment, however 5 of these patients still have sensory dysesthesia. The outcome was: 67.1% excellent (77 patients), 26.3% good (30 patients), 6.1% fair (7 patients). CONCLUSION: The far lateral approach is a minimally invasive and safe procedure with low complication rates.

Parapharyngeal prestyloid vagal paraganglioma.

Vagal paragangliomas (VPs) are rare tumors arising from paraganglionic tissue within the vagal nerve's perineurium. Usually, benign vascular tumors, VPs tend to invade the surrounding structures. Herein, we report the case of a VP presenting as a neck mass, which was evaluated as a glomus caroticum tumor preoperatively. A 65-year-old female complaining of a left-sided neck mass and intermittent hoarseness was assessed and operated on for possible glomus caroticum tumor. During the tumor excision, the vagal nerve was also involved, and hence, sacrificed. Histopathological examination revealed an encapsulated tumor associated with a nerve and ganglion and immunohistochemical staining tested positive for succinate dehydrogenase, confirming the diagnosis of VP. Postoperative residual hoarseness was corrected by vocal rehabilitation. While evaluating a retropharyngeal prestyloid neck mass, a VP should always be considered. Surgical excision involving vagal scarification, followed by vocal rehabilitation may be the appropriate treatment strategy.

A rare case of cervical metastatis of glioblastoma after cranial tumor resection: case report and review of literature.

Glioblastoma multiforme (GBM) is the most common and the most malignant primary intracranial tumor in adults. GBM extraneural metastases occur in only approximately 0.2-0.4% of patients. We present a case of a cervical metastasis of glioblastoma after cranial tumor resection. In concord with case presentation, we reviewed the metastatic location and metastasis time of the gliablastomas seen in the literature.

Spinal paragangliomas: Surgical treatment and follow-up outcomes in eight cases.

Paragangliomas are neuro-endocrine tumors originating from the adrenal gland. They are usually benign and nonfunctioning, rarely seen in central nervous system. More than 90% of central nervous system paragangliomas are manifested as carotid and glomus jugulare tumors. Spinal paragangliomas are quite rare.The study was conducted through retrospective analysis of the files of the patients who had undergone surgery with pre-diagnosis of spinal intradural tumor between 2011 and 2017 and diagnosed with paraganglioma.A total of 8 patients (4 females and 4 males) were included in the study. Mean age of the patients was 51.1 years (28-64). Time to admission was mean 6.5 months (3 weeks-24 months). Recurrence was not observed in 7 patients, 1 patient is being followed up due to residual tumor.Treatment may be achieved through recognizing malignant transformation in patients who were not diagnosed histopathologically. We consider that quality of life of the patients may be improved through this way.

Nontraumatic Intradiploic Epidermoid Cyst and Older Age: Association or Causality?

BACKGROUND: Intradiploic epidermoid cysts (IEC) are rare, benign lesions derived from ectodermal remnants during neural tube closure. Their origin is still debated or unknown. OBJECTIVE: Analyzing of the patients with intradiploic epidermoid cysts operated in the authors' department. METHODS: The patients with IEC who were operated in the authors' department between January 2014 and December 2015 were investigated from data file. RESULTS: Six patients with IEC were found, reviewed the literature, and noted that these cysts usually occur in adults. There are only 3 young cases that occurred after head injury. CONCLUSION: It was shown that the nontraumatic IEC are more frequent in older ages. In youngs, it can generally be embryologic or rarely of mechanical origin following trauma. Cranial trauma may be important for developing of IEC. Trauma may lead to inclusion of epidermal cells into the diploe of the skull and may be a reason of intradiploic epidermoid cyst in older age. The effect of older age, and gender difference on occurrence should be investigated.

How Reliable Is Pupillary Evaluation Following Subarachnoid Hemorrhage? Effect of Oculomotor Nerve Degeneration Secondary to Posterior Communicating Artery Vasospasm: First Experimental Study.

BACKGROUND AND STUDY AIM: Basic neurophysiologic principles of the light reflex are well known. However, the effects of degenerated axon densities of oculomotor nerves (OMNs) secondary to posterior communicating artery (PComA) vasospasm following subarachnoid hemorrhage (SAH) have not been investigated. Our aim was to study this subject. METHODS: This study was conducted on 19 rabbits. There was a control group of five animals, a sham group of five animals in which saline was injected into the cisterna magna and a study group of nine animals in which homologous blood was injected into the cisterna magna. Pupillary diameters were measured for 1 week, then the animals were decapitated. The normal and degenerated axon densities of the OMNs were examined by stereological methods. Vasospasm indexes (VSIs) of posterior communicating arteries (PComAs) supplying OMNs were estimated and analyzed statistically. RESULTS: The pupillary diameter was 5.439 ± 368 µm, and the mean axon density of the OMNs was 0.924 ± 324/mm3 in the control group. The pupillary diameter and degenerated axon density of the OMNs in animals of the sham group were 6.980 ± 0.370 µm and 36 ± 8/mm3, respectively. The pupillary diameter was 9.942 ± 653 µm, and degenerated axon density of the OMNs was 265 ± 57/mm3 in animals with SAH. The mean VSI values of PComAs were 0.927 ± 0.224 in the control group, 1.542 ± 0.257 in the sham group, and 2.321 ± 0.324 in the SAH group. CONCLUSION: We found a linear relationship between the axon density of the OMNs and pupillary diameters. High degenerated neuron density in the OMNs may be responsible for an unresponsive pupillary that has not been mentioned in the literature.

Predictive Role of External Carotid Artery Vasospasm on Cerebral Ischemia After Subarachnoid Hemorrhage: Experimental Study.

AIM: Cerebral vasospasm after subarachnoid hemorrhage (SAH) may lead to a devastating neurological outcome by inducing cerebral ischemia. However the role of external carotid artery (ECA) vasospasm has been rarely reported in the literature. The aim of this study was to elucidate the effect of ECA vasospasm on cerebral ischemia related neurodegeneration in the cerebral cortex after SAH. MATERIAL AND METHODS: This study was performed on 23 rabbits, divided into three groups: control (n=5), sham (n=5), and SAH (n=13). Experimental SAH was performed by injecting 0.75 mL auricular arterial homologous blood into the cisterna magna. After three weeks, the animals were decapitated and the common carotid arteries with their external and internal branches and the brains were examined histopathologically. Vasospasm indexes (VSI) of ECAs and internal carotid arteries (ICAs) and degenerated glial cell numbers of temporal cortices (n/mm3) were estimated stereologically and the results were compared statistically. RESULTS: Temporal cortex glial cell density was estimated as 136.950±9.257/mm3 in normal rabbits, 131.324±7.987/mm3 in sham, 112.320±6.112/mm3 in light, and 97.543±5.432/mm3 in severe ECA vasospasm. The mean VSI values of ECA of all groups were 1.95±0.21, 2.15±0.29, 2.95±0.65 and 3.12±0.276, respectively. Statistical differences between the VSI values of ECA and degenerated neuron densities in temporal cortices were significant (p < 0.005). CONCLUSION: ECA vasospasm was observed to have a more important predictive role on the serious cerebral ischemia and neuronal degeneration after SAH. The mechanism may be related to ischemia of the parasympathetic ganglia of the lower cranial nerves and dorsal root ganglion.

Analysis of diabetes-related cerebellar changes in streptozotocin-induced diabetic rats.

BACKGROUND/AIM: Diabetic peripheral neuropathy has been extensively studied and reported, but the number of studies that have investigated diabetes-related changes in the central nervous system are limited, with even fewer studies on the cerebellum. The aim of this experimental study was to perform a histologic analysis of the diabetes-related changes in the cerebellums of diabetic rats. MATERIALS AND METHODS: Twenty Sprague Dawley rats weighing between 200 and 220 g were included in the study. Diabetes was induced in 14 of these rats by a single intraperitoneal injection of 65 mg/kg streptozotocin dissolved in saline, while 6 animals constituted the control group. The induction of diabetes was confirmed by measuring the blood glucose levels in the tail blood with a glucometer. Levels equal to or above 200 mg/dL were considered diabetic. Induction of diabetes failed in 3 animals, who were then excluded from the study. RESULTS: Light and electron microscopic studies revealed that the neurons and glial cells in the diabetic group had degenerative changes, irregularities and disruption in the myelin sheath, disintegration in the presynaptic vesicles, engorged axon terminals, perivascular and mitochondrial swelling, mitochondrial structural changes, and fragmentation of the neurofilaments. CONCLUSION: Ultrastructural alterations are observed in the diabetic rat cerebellum.

Cervical disc hernia operations through posterior laminoforaminotomy.

OBJECTIVE: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. MATERIALS AND METHODS: We retrospectively evaluated 35 patients diagnosed with posterolateral cervical disc herniation and cervical spondylosis with foraminal stenosis causing radiculopathy operated by the posterior cervical keyhole laminoforaminotomy between the years 2010 and 2015. RESULTS: The file records and the radiographic images of the 35 patients were assessed retrospectively. The mean age was 46.4 years (range: 34-66 years). Of the patients, 19 were males and 16 were females. In all of the patients, the neurologic deficit observed was radiculopathy. The posterolaterally localized disc herniations and the osteophytic structures were on the left side in 18 cases and on the right in 17 cases. In 10 of the patients, the disc level was at C5-6, in 18 at C6-7, in 2 at C3-4, in 2 at C4-5, in 1 at C7-T1, in 1 patient at both C5-6 and C6-7, and in 1 at both C4-5 and C5-6. In 14 of these 35 patients, both osteophytic structures and protruded disc herniation were present. Intervertebral foramen stenosis was present in all of the patients with osteophytes. Postoperatively, in 31 patients the complaints were relieved completely and four patients had complaints of neck pain and paresthesia radiating to the arm (the success of operation was 88.5%). On control examinations, there was no finding of instability or cervical kyphosis. CONCLUSION: Posterior cervical laminoforaminotomy is an alternative appropriate choice in both cervical soft disc herniations and cervical stenosis.

Uncovering a New Cause of Obstructive Hydrocephalus Following Subarachnoid Hemorrhage: Choroidal Artery Vasospasm-Related Ependymal Cell Degeneration and Aqueductal Stenosis-First Experimental Study.

BACKGROUND: Hydrocephalus is a serious complication of subarachnoid hemorrhage (SAH). Obstruction of the cerebral aqueduct may cause hydrocephalus after SAH. Although various etiologic theories have been put forward, choroidal artery vasospasm-related ependymal desquamation and subependymal basal membrane rupture as mechanisms of aqueductal stenosis have not been suggested in the literature. METHODS: This study was conducted on 26 hybrid rabbits. Five rabbits were placed in a control group, 5 were placed in a sham group, and the remaining rabbits (n = 16) were placed in the SAH group. In the first 2 weeks, 5 animals in the SAH group died. The other 21 animals were decapitated after the 4-week follow-up period. Choroidal artery changes resulting from vasospasm, aqueduct volume, ependymal cell density, and Evans index values of brain ventricles were obtained and compared statistically. RESULTS: Mean aqueduct volume was 1.137 mm(3) ± 0.096, normal ependymal cell density was 4560/mm(2) ± 745, and Evans index was 0.32 ± 0.05 in control animals (n = 5); these values were 1.247 mm(3) ± 0.112, 3568/mm(2) ± 612, and 0.34 ± 0.15 in sham animals (n = 5); 1.676 mm(3) ± 0.123, 2923/mm(2) ± 591, and 0.43 ± 0.09 in animals without aqueductal stenosis (n = 5); and 0.650 mm(3) ± 0.011, 1234/mm(2) ± 498, and 0.60 ± 0.18 in animals with severe aqueductal stenosis (n = 6). The choroidal vasospasm index values were 1.160 ± 0.040 in the control group, 1.150 ± 0.175 in the sham group, 1.760 ± 0.125 in the nonstenotic group, and 2.262 ± 0.160 in the stenotic group. Aqueduct volumes, ependymal cell densities, Evans index, and choroidal artery vasospasm index values were statistically significantly different between groups (P < 0.05). CONCLUSIONS: Ependymal cell desquamation and subependymal basal membrane destruction related to choroidal artery vasospasm may lead to aqueductal stenosis and hydrocephalus after SAH.

The Anatomy of the Posterior Commissure.

AIM: The connections of posterior commissure are defined. Its fibers mediate the consensual light reflex by interconnecting the pretectal nuclei. The fiber connections from the thalamic, pretectal, superior colliculus and the habenular nuclei are known, but they have not been shown anatomically. The present study is a fiber dissection study to define the anatomy of the posterior commissure. MATERIAL AND METHODS: Twenty formalin-fixed sheep heads were used in the study. The specimens were fixed in 10% formalin solution for 3 weeks. The arachnoidal and vascular structures were removed by using a surgical microscope magnification (x6-x40) and brains were again fixed for 4 weeks at -20°C. The fiber dissections were performed at Marmara University, Rhoton Laboratory. Also, a radiological tractographic study was carried on five healthy volunteers to see the posterior commissure cortical connections. RESULTS: In fifteen sheep brains, the dimensions of the posterior commissure were measured as 1.36 mm (range 0.5-2.5 mm) width, and as 4.6 mm (range 3-6 mm) length. In the dissection study, a frontotemporooccipital fascicle was observed to connect with the fibers of the posterior commissure. Diffusion tensor imaging scans showed the frontotemporooccipital tract to extend to posterior commissural region. CONCLUSION: To our knowledge, this is the first anatomical and tractographic study regarding the posterior commissure. However, further human cadaveric studies are necessary.

Superior medullary velum: anatomical-histological study in the sheep brain and a preliminary tractographic study in the human brain.

AIM: To study the anatomy, histology and fiber relations of the superior medullary velum. MATERIAL AND METHODS: Ten previously frozen and formalin-fixed sheep brains were used. The fiber dissection was done using the operating microscope at the Rhoton Anatomy Laboratory of Marmara Faculty of Medicine. A tractographic study was conducted on five volunteer patients to see the fiber anatomy of the superior medullary velum. RESULTS: The average thickness and length was found to be 0.296 mm (range 0.09-1 mm) and 4.25 mm (range 3.25-4.5 mm) respectively. Histologically, the superior medullary velum consisted of cuboidal layer of ependymal cells on the anterior surface related to fourth ventricle. The subependymal layer contained hypocellular fibrillary zone with few glial cells, and the outer layer consisted of thin layer of fibroblasts. Under the hypocellular fibrillary zone, abundant axons and organized structures were observed. Tractographically, only a few fibers were identified on diffusion-tensor imaging (DTI). CONCLUSION: We could not identify a distinct tract anatomically and neuron cells histologically. Neuron-like cells and organized structures were observed on immunohistochemical analysis. Also a few tracts were observed on DTI study as an ascending pathway from spinal tracts to the superior medullary velum. Further studies including human cadaveric, histologic and fiber tractographic investigations are needed to say that it is harmless to divide this anatomical structure.

Echinococcus alveolaris: presenting as a cerebral metastasis.

Echinococcus multilocularis (EM) is caused by the larval stage of the tapeworm. The main endemic regions for human alveolar echinococcosis are Central Europe, Russia, Turkey, Japan, China, Eastern France, North America. EM is an endemic disease in Turkey and especially common in the eastern Anatolia Region as seen in our case. The liver is the primary focus of the disease, cerebral localization is rare. Cerebral hydatid disease is approximately 5% of alveolar hydatid cases and generally considered to be fatal. Surgical treatment should be considered whenever possible. We present a case of cerebral alveolar hydatid disease that was thought to be cerebral metastasis.