Demonstration of Microsurgical Technique and Nuances for the Obliteration of Complex Intracranial Dural Arteriovenous Fistulas in Three Consecutive Cases: Operative Video.

An intracranial dural arteriovenous fistula (DAVF) is an uncommon acquired dural shunt between an artery and a vein without a parenchymal nidus. DAVF occlusion may be achieved using either endovascular or open surgical means. Combining both techniques is also frequently used in clinical practice. In this video, we present 3 patients with Borden type III, complex intracranial DAVFs. The first patient presented with intracranial hemorrhage and underwent a successful microsurgical obliteration of the fistula in the tentorium. Two other patients had DAVFs that were incidentally found. Both underwent embolization procedures, which did not result in complete DAVF obliteration. Both patients then subsequently underwent microsurgical obliteration of these DAVFs. All 3 patients had very good outcomes. In 2 of these cases, we performed indocyanine green video angiography to identify fistulous connections. As demonstrated in this Video 1, microsurgical obliteration of DAVFs is relatively straightforward. This provides a valuable treatment option of some selected DAVFs and should be considered as a primary initial treatment option of complex DAVFs in certain locations. Open surgical obliteration is the best possible, most durable, and most effective therapeutic option when there are failures or shortcomings with endovascular management.

Comparison of ependymomas and medulloblastomas located in the posterior cranial fossa: An anatomical and histopathological study.

Posterior fossa tumors (PFTs) include medulloblastomas, atypical teratoid/rhabdoid tumors, pilocytic astrocytomas, ependymomas, and brainstem gliomas. We evaluated patients with surgery at our clinic, comparing epidemiological, clinical, radiological, and pathological characteristics of medulloblastoma and ependymoma to identify factors that might assist preoperative diagnosis, help to develop treatment algorithms, and have prognostic value after surgery. Pediatric patients from 0 to 16 and young adults from 16 to 29 years of age with surgery for pathologically confirmed ependymomas or medulloblastomas between January 2014 and January 2020 were eligible. The study included 19 patients, seven with ependymoma (37%) and 12 with medulloblastoma (63.2%). The ependymoma patients were 5.29 ± 5.85 years of age, the medulloblastoma patients were 11.58 ± 8.17 years of age, and 16 patients (84%) were children.Fifteen patients (79%) presented with signs of increased intracranial pressure and four (21%) presented with cerebellar findings. MRI found that 74% (14) of the PSTs were located in the midline, including six of the seven ependymomas (86%) and eight of the 12 medulloblastomas (67%). Enhancement was significantly greater in medulloblastomas compared with ependymomas (p = 0.022). In according to pathology results; synaptophysin, NSE, chromogranin and 50% GFAP positivity were observed in medulloblastoma. Ependymomas were S100 (43%) and vimentin (29%) positive. Ependymoma patients were younger than medulloblastoma patients and more were female. There were no significant differences in the clinical findings, but ependymomas were larger and had greater rates of enhancement and spinal metastasis compared with medulloblastomas.

Cranially migrated lumbar intervertebral disc herniations: A multicenter analysis with long-term outcome.

OBJECTIVE: Risk factors of cranial migration were investigated in patients with lumbar disc herniation (LDH) that migrated in the cranial direction and the long-term outcomes are discussed in this study. MATERIALS AND METHODS: Patients who underwent surgery for LDH at four different centers between 2012 and 2017 were studied. Extraligamentous discs were located in the lateral part of the posterior longitudinal ligament (PLL) within the spinal canal of the axial plane, and subligamentous discs were located under the PLL. The extent of cranial migration was calculated as a percentage of the height of the migrated corpus. Based on the extent of cranial migration, partial hemilaminectomy or hemilaminectomy was performed at different rates in each patient and the amount of laminectomy performed was recorded. During surgery, all free fragments were attempted to be removed. The appropriate technique was decided intraoperatively, and the surgery was performed on an individual patient basis. RESULTS: Of 1289 patients who underwent surgery for LDH, 654 (50.73%) had caudal migration, 576 (44.68%) had migration at the level of the disc, and 59 (4.57%) had cranial migration. Analysis of 59 patients with cranial migration according to the localization of the disc fragment revealed that 31 had extraligamentous and 28 had subligamentous fragments (P = 0.024). CONCLUSIONS: Extraligamentous intervertebral disc fragments migrate more cranially than subligamentous intervertebral fragments. The anatomy of the PLL that varies along the corpus is the main reason for the weakness of the resistance of the disc material to the dorsolateral region, direction of discrete force vectors, and orientation of the disc fragment due to torsional vertebral movements.

The Tonsillouvular Fissure Approach: Access to Dorsal and Lateral Aspects of the Fourth Ventricle.

OBJECTIVE: Although approaches to the fourth ventricle (FV) have been studied well, approaches to the lesions located in the dorsal and lateral aspects of the FV have not been shown in anatomic or clinical studies. The aim of this study is to show for the first time in the literature the tonsillouvular fissure approach (TUFA) in anatomic dissections and its use in surgical series. METHODS: For anatomic studies, 4 formalin-fixed human cadaveric heads infused with colored silicone and 10 cerebellar specimens were dissected in a stepwise manner. Records of 12 patients operated on via TUFA were also retrospectively reviewed. RESULTS: Neurosurgical anatomy and critical steps of TUFA were described in detail. Among 12 patients with lesions around the FV (4 cavernous malformation, 2 pilocytic astrocytoma, 2 hemangioblastoma, 1 B-cell lymphoma, 1 metastatic papillary carcinoma, 1 dermoid cyst, and 1 arteriovenous malformation), 11 gross total and 1 subtotal resection were achieved via TUFA without any mortality or morbidity. Comparative analyses of 4 surgical approaches to FV (TUFA, telovelar/cerebellomedullary fissure, supratonsillar/tonsillobiventral lobule fissure, and transvermian approaches) were also presented. CONCLUSIONS: TUFA provides a direct route and excellent surgical view to lesions around the FV, particularly on dorsal and lateral aspects, inferior vermis, and medial part of the dentate nucleus and cerebellar peduncles. It minimizes traversing the normal cerebellar tissue compared with a transvermian approach.

Emergency resection of brainstem cavernous malformations.

Brainstem cavernous malformations (CMs) pose significant challenges to neurosurgeons because of their deep locations and high surgical risks. Most patients with brainstem CMs present with sudden-onset cranial nerve deficits or ataxia, but uncommonly patients can present in extremis from an acute hemorrhage, requiring surgical intervention. However, the timing of surgery for brainstem CMs has been a controversial topic. Although many authors propose delaying surgery into the subacute phase, some patients may not tolerate waiting until surgery. To the best of the authors' knowledge, emergency surgery after a brainstem CM hemorrhage has not been described. In cases of rapidly progressive neurological deterioration, emergency resection may often be the only option. In this retrospectively reviewed small series of patients, the authors report favorable outcomes after emergency surgery for resection of brainstem CMs.

Posterior Epidural Migration of a Sequestered Lumbar Intervertebral Disc Fragment.

AIM: Posterior epidural migration of a sequestered lumbar intervertebral disc fragment (PEMSLIDF) is an extremely rare condition published so far only as case reports or small case series (ranging between 2 to 8 cases). Diagnosing this condition is often challenging and the diagnosis is usually made intraoperatively. The affected patients usually suffer cauda equina syndrome (CES). In the present study, we aimed to discuss the clinical and radiological findings, types and features of surgical therapies, and outcomes of 9 patients with PEMSLIDF. MATERIAL AND METHODS: This study included 9 (0.36%) patients with PEMSLIDF among 2470 patients who underwent lumbar disc hernia surgery between August 2002 and September 2012. The preoperative clinical and radiological properties of the patients were evaluated. The postoperative outcomes were assessed using neurological examination, radiological imaging, visual analog scale (VAS) and modified Odom criteria. RESULTS: As far as we know, this study is the largest case series examining the characteristics of PEMSLIDF. Seven (77.8%) of our patients were male and 2 (22.2%) were female and they had a mean age of 49.5 years (range 28-70 years). The mean duration from symptom onset to hospital admission was 7.4 days. Seven patients had CES. All patients underwent sequestrectomy and discectomy via posterior microsurgery. The patient outcomes were evaluated by the Modified Odom criteria and the outcome was excellent in two (22.2%) patients, good in 4 (44.5%), fair in 2 (22.2%), and poor in 1 (11.1%). CONCLUSION: The entire free fragment can usually be excised via the posterior microsurgery technique. Early surgical treatment is of great importance to prevent more serious neurological deficits.

The effectiveness of transforaminal epidural steroid injections on radicular pain, functionality, psychological status and sleep quality in patients with lumbar disc herniation.

BACKGROUND: The significance of fluoroscopy-guided transforaminal epidural steroid injections (TFESI) in the treatment of lumbar disc herniation (LDH) is well known. The aim of our study is to investigate the effectiveness of TFESI on radicular pain, functionality, psychological status, and sleep quality in patients with LDH. METHODS: Seventy-five LDH patients (36 males, 39 females) were enrolled in the study. All patients received a fluoroscopically guided TFESI (betamethasone 40 mg, lidocaine 2%). Also all patients were evaluated according to (with the visual analogue scale) radicular pain, Oswestry disability index (ODI), hospital axiety and depression scale, and Pittsburgh sleep quality index (PSQI) at baseline, at two weeks, and 12 months post injections. RESULTS: Mean age was 46.4 ± 12.5. When compared to baseline measurements there were significant improvements in radicular pain, ODI, modified schober, Laseque angle, finger to floor distance, depressive symptoms and PSQI scores at two weeks and 12 months after injection. Improvement of at least 50% in radicular pain relief, ODI score and sleep quality index was detected at two weeks 83%, 71%, 69% respectively. This rate showed regression at 12 months of 73%, 65% and 62% respectively. Duration of symptoms was significantly negatively correlated with changes in scores of radicular pain, ODI, depressive symptoms, and PSQI. There were no significant correlations with symptom duration and anxious symptoms. CONCLUSION: Fluoroscopy guided TFESI had positive effects on radicular pain, functionality, depressive symptoms and sleep quality in management of LDH.

Local Tissue Electrical Resistances in Transpedicular Screw Application in the Thoracolumbar Region.

AIM: To determine local tissue electrical resistance differences generated during a screw pass from the pedicle to another tissue rather than determining all individual electrical tissue resistance values. MATERIAL AND METHODS: We attempted to measure electrical resistance values of regional tissues in addition to fluoroscopic imaging during application of fixation via a transpedicular screw. We also attempted to detect local tissue electrical resistance alterations in case of malposition of the screw inside the pedicle. For this purpose, local tissue electrical resistances of 10 transpedicular tracks opened with standard track openers bilaterally in 5 vertebrae, and of spinal cord accessed by puncturing the medial walls of three vertebrae in a cadaver were measured. These resistance differences were not only measured in human cadaveric tissue but also in 36 pedicles belonging to a total of 18 vertebrae between Th 1-S1 vertebrae of a sheep cadaver. Both medial and lateral walls were drilled to measure local tissue resistance differences in a sheep cadaver. RESULTS: Our results indicated that local tissue electrical resistance changes were statistically significant in both human and sheep cadaver. CONCLUSION: It is possible to prevent screw malposition using a simple and cheap electrical resistance measurement. Local tissue electrical resistance measurement during transpedicular screw insertion is a safe, simple, cheap, and practical method.

The Impact of the Stage and Tumor Size on Rare Brain Metastasis of Cervical Cancer.

AIM: To investigate the clinical features, prognostic factors and survival times of cervical cancer patients with brain metastasis. MATERIAL AND METHODS: We retrospectively reviewed the medical records of 820 patients with cervical cancer. Data were analyzed using SPSS version 12.0 statistical software (SPSS, Chicago, IL, USA). Overall survival, time interval from diagnosis of cervical cancer to identification of brain metastasis, and median survival time after diagnosis of brain metastasis were calculated using Kaplan-Meier curve analysis. The log-rank test was used to compare differences in survival. Differences were assumed statistically significant when p-values were < 0.05. RESULTS: The incidence of brain metastases from cervical cancer in our institution was 1.82% (15/820) over a ten-year period. The median time interval from diagnosis of cervical cancer to detection of brain metastasis was 12.5 months (range: 2.9-91.9 months). Stage and tumor diameter were found to be significant relating to the interval from diagnosis of cervical cancer to detection of brain metastasis (p=0.001 for both). CONCLUSION: This study provides much information about the prognosis of patients with brain metastases from cervical cancer and highlights the importance of initial stage and tumor diameter when determining the time interval until development of brain metastasis.

A modified technique for the treatment of isthmic spondylolisthesis.

AIM: To describe a modified technique for the treatment of single level, isthmic spondylolisthesis (IS) MATERIAL and METHODS: Forty-two patients who underwent posterior lumbar interbody fusion (PLIF) with spinolaminar autologous bone graft for the treatment of isthmic spondylolisthesis between May 2007 and November 2011, were retrospectively reviewed. All patients underwent total removal of the spinolaminar process, total discectomy and endplate decortication, and proper size spinolaminar autologous bone graft was sequentially inserted into the disc space with posterior instrumentation. Outcomes of the study included visual analogue scale (VAS), Oswestry disability index (ODI), and radiographic fusion. RESULTS: The average duration of follow-up was 3.5 years. Neither has implant failure been observed nor has revision been required so far. The mean Oswestry Disability Index improved from 53% to 9.5%, and visual analog scale for back pain from 8.5 to 3.8 at the first month and 1.3 at the sixth month postoperatively. Visual analog scale for leg pain from 8.3 to 1.4 at the first month and 0.8 at the sixth month postoperatively. All patients had clinical and radiographic evidence of solid fusion without any need for revision. CONCLUSION: The modified posterior lumbar interbody fusion and posterior instrumentation technique is a safe and effective treatment for isthmic spondylolisthesis.

Co-occurrence of lumbar spondylolysis and lumbar disc herniation with lumbosacral nerve root anomaly.

Lumbosacral nerve root anomalies are the leading cause of lumbar surgery failures. Although co-occurrence of lumbar spondylolysis and disc herniation is common, it is very rare to observe that a nerve root anomaly accompanies these lesions. A 49-year-old male patient presented with sudden-onset right leg pain. Examinations revealed L5/S1 lumbar spondylolysis and disc herniation. At preoperative period, he was also diagnosed with lumbosacral root anomaly. Following discectomy and root decompression, stabilization was performed. The complaints of the patient diagnosed with lumbosacral root anomaly at intraoperative period were improved at postoperative period. It should be remembered that in patients with lumbar disc herniation and spondylolysis, lumbar root anomalies may coexist when clinical and neurological picture is severe. Preoperative and perioperative assessments should be made meticulously to prevent neurological injury.

Surgical therapy of a vertebral artery aneurysm with saccular and fusiform segments.

Vertebral artery aneurysms form a group of aneurysms having high rates of rebleeding, morbidity, and mortality, poor treatment outcomes, as well as low rate of surgical treatment. Examinations for subarachnoid bleeding revealed a vertebral artery aneurysm with a diameter of 12 mm in a 67-year-old man who presented with headache. The vertebral artery aneurysm with saccular and fusiform segments was shrunk and clipped via lateral left suboccipital approach. No neurologic deficit was present at the postoperative period. Control digital subtraction angiography showed complete shrinkage of aneurysm with continued blood flow and no residue. Clinical findings, treatments, and surgical approaches of VA aneurysms are different from anterior and posterior circulation aneurysms. Microneurosurgical clipping is the most effective treatment of vertebral artery aneurysms in suitable cases. Although endovascular intervention is commonly applied as therapeutic modality for patients with vertebral artery aneurysm, researchers have also emphasized that saccular vertebral aneurysms with fusiform extension can also be surgically treated in suitable cases.

Efficacy of dexamethasone on penicillin-induced epileptiform activity in rats: an electrophysiological study.

Corticosteroids are extensively used in treatment of many diseases. In neurosurgery practice, dexamethasone (DEX) is commonly used particularly in cerebral edema secondary to brain tumors, head trauma, and central nervous system infections. There are some uncertainties surrounding the secure use of DEX in patients with epilepsy or seizures induced by diseases of the central nervous system such as head trauma and brain tumors. Despite its extensive use, the effect of DEX on epileptiform activity is unclear. In this study the effect of DEX on epileptiform activity was investigated in rats. The effects of 1, 3, and 10mg/kg DEX on epileptiform activity was compared with effects of antiepileptic drugs commonly employed in treatment of epilepsy, namely phenytoin (PHT) 50mg/kg and levetiracetam (LEV) 50mg/kg that were administered intraperitoneally for 1 week. All groups were administered intracortical penicillin (500IU) to induce epileptiform activity. DEX at the doses of 3mg/kg and 10mg/kg significantly reduced spike frequencies compared to the initial values. In conclusion, we think that DEX can effectively decrease the epileptiform activity.

Evaluation of risk factors affecting hospital-acquired infections in the neurosurgery intensive care unit.

The aim of the present study was to identify nosocomial infections (NIs), and their associated risk factors, in patients treated in the neurosurgery intensive care unit (NICU) of our hospital. Patients determined to have NIs between January 2008 and December 2012 were included in the study. Each patient's age, gender, microbiological culture results, underlying conditions, type of NIs, device utilization, total parenteral nutrition, reason for hospitalization, Glasgow score, and treatment were recorded and evaluated using statistical analysis. Risk factors for NIs were analyzed with a logistic regression model. During the five-year period, 60 NI episodes were detected in 56 out of 1643 patients. The mean age of the patient population was 33.3 (1-79) years. Of the patients, 22 were female and 34 were male. The overall incidence rate (NIs/100) and incidence density (NIs /1000 days of stay) of NIs were 3.65% and 6.5/1000 patient days, respectively. Regardless of the year of surveillance, the three most commonly detected NIs were bloodstream infection, shunt infection, and ventilator-associated pneumonia. No statistically significant difference was detected between infected and uninfected patients in terms of sex, age, blood transfusions, or mannitol and steroid use (p ≥ 0.05). In the present study, Glasgow scores, the frequency of prior usage of broad-spectrum antibiotics, and NICU stay durations were significantly higher among patients with infections (p < 0.001). Univariate analysis demonstrated that a low Glasgow score, re-operation, and use of mechanical ventilation were risk factors for NIs. We identified low Glasgow coma scores, long hospital stay duration, use of wide spectrum antibiotics, mechanical ventilation, total parenteral nutrition, and re-operation as risk factors for NIs.

Three-dimensional analysis of foramen magnum and its adjacent structures.

The goal of this effort is to evaluate the anatomy of the foramen magnum (FM) using 3-dimensional computed tomography (3D CT), and determine whether or not the anatomical features of vascular structures and condylar foramen (CF) affect the types of FM.The CT angiography records of 101 patients (44 men and 57 women) were retrospectively examined in this study. Details of the FM, CF, and the vertebral and basilar arteries were examined using maximum intensity projection and 3D rendering images. The average age of the 101 patients was 45.28 ± 16.3 years. The 8 types of FM, in order of their frequency of occurrence, are as follows: round (19 cases; 18.8%), 2 semicircles (18; 17.8%), egg-shaped (15; 14.9%), hexagonal (14; 13.9%), tetragonal (11; 10.9%), oval (11; 10.9%), pentagonal (9; 8.9%), and irregular (4; 4%). There was no statistically significant relationship between the anatomical features of the vertebral and basilar arteries and the CF with the different types of FM (P ≥ 0.05). In our study, the diameter of the anteroposterior (AP) FM was 34.7 ± 3.6 mm, and the transverse (T) diameter was 29.5 ± 2.5 mm. The AP and T diameters were significantly higher in men than in women (P = 0.006 and P ≤ 0.001, respectively).Our study revealed that 3D CT is a safe and easy method for visualizing the anatomical structure of the FM and neighboring structures. Furthermore, this study was the first to demonstrate that there is no correlation between the 8 types of FM and the vertebral artery, basilar artery, and CF.

Magnetic resonance spectroscopic imaging associated with analysis of fluid in cystic brain tumors.

OBJECTIVE: There is a growing interest in cystic lesions of the brain. Examining the cyst content of brain tumors may contribute in determining the malignancy of the given tumor accompanied by a cyst. METHODS: In this work, samples of cyst fluid from 18 patients with brain tumor were collected and studied biochemically regarding their protein, lactate contents and pH values; magnetic resonance spectroscopic images of these patients were also compared. We investigated the relation between the grade of malignancy and the lactate concentration and the discrepancy between the high levels of lactate in cysts and their alkaline environment. RESULTS: There appears to be a positive relation between the grade of malignancy and the concentration of lactate in the cysts' fluid. A significant two-fold increase in lactate concentration in malignant tumors cysts has been found as compared with the more benign tumor cysts (p<0.001). This increase in lactate level is probably because of aerobic glycolysis, which causes lactate production by the tumor. DISCUSSION: High lactate levels found through magnetic resonance spectroscopy are positively related to the grade of tumor malignancy. The pH values in the cyst fluids were above normal, resulting to a discrepancy in high levels of lactate in the cyst and the alkaline environment. This suggests efflux of H+ ions by a Na/H exchange mechanism to compensate for the change of pH.

Ruptured distal anterior choroidal artery aneurysm.

This report describes a patient with a rare distal anterior choroidal artery (AChoA) aneurysm that developed a right intracerebral haematoma and intraventricular haemorrhage and was treated by surgical exploration and clipping via a transtemporal/ventricular approach. The patient was discharged neurologically intact. We review the literature related to these rare aneurysms within the temporal horn, and the surgical anatomy of the AChoA.

Total removal of cervicothoracic intramedullary 160-mm-long spinal cord ependymoma: a rare case report.

Ependymomas are neuroectodermal tumours arising from ependymal cells of the ventricular system, choroid plexus, filum terminale, or central canal of the spinal cord. We report on a 160-mm-long cervicothoracic intramedullary spinal cord ependymoma. The tumour was totally removed; no radiotherapy was used as an adjunctive therapy. Postoperative magnetic resonance imaging confirmed that the tumour had been totally removed.