Flow diverter stent treatment for unruptured supraclinoid segment internal carotid artery aneurysms: a Turkish multicenter study.

OBJECTIVE: Despite the relatively high success of surgical clipping of supraclinoid segment aneurysms of the internal carotid artery (ICA), flow diverter (FD) stent therapy is becoming increasingly used for these aneurysms. This study aims to evaluate the characteristics of FD placement for unruptured ICA supraclinoid segment aneurysms at 6 different centers with different experience levels in Türkiye. METHODS: In this retrospective, multicenter study, the authors reviewed the demographic information, aneurysm shape/dimensions (neck, aspect ratio, dome/neck ratio, and maximum diameter), preoperative antiplatelet regimen, FD stent brand, perioperative complications, intervention time, clinical (modified Rankin Scale) and radiological (O'Kelly-Marotta [OKM] grading scale) outcomes, and follow-up time of 54 patients. RESULTS: A total of 55 interventions for 61 aneurysms (58 supraclinoid ICA aneurysms) were performed in the 54 patients included in the study. The female/male ratio in this population was 44/10, and the mean age was 53.5 ± 13.6 (range 21-82) years. The most common form and location of the aneurysms were saccular 91.4% (53/58) and ophthalmic segment 69% (40/58), respectively. The preferred antiplatelet regimen was acetylsalicylic acid plus ticagrelor 50% (27/54). The overall complication rate was 25.5% (14/55), and the mean follow-up time was 25.76 ± 17.88 months. The successful radiological outcome (OKM grade C or D) rate at the 6-month follow-up was 92.6%. No perioperative complications led to any permanent or transient neurological deficit. CONCLUSIONS: The results of this first multicenter study evaluating FD stent use for unruptured ICA supraclinoid segment aneurysms showed that FD stent treatment is a feasible method for replacing clipping and coil embolization with manageable complications and a high success rate.

The importance of IDH1, ATRX and WT-1 mutations in glioblastoma.

Numerous genetic pathways associated with glioblastoma development have been identified. In this study, we investigated the prognostic significance of IDH1 and ATRX mutations and WT-1 and p53 expression in glioblastomas and that of surgical methods, radiotherapy and chemotherapy. 83 patients with glioblastomas were retrospectively evaluated. Immunohistochemical analysis was performed for IDH1, ATRX and WT-1 expression. Tumour cells were positive for IDH1 in 9.6% of the patients. In 4.8% of the patients, loss of ATRX expression was observed in tumour cells; 86.7% of the patients were WT-1 positive, and 12.05% of the patients were p53 positive. No statistically significant difference was found in the progression-free and overall survival according to IDH1, ATRX, WT-1 and p53 expression. There was a statistically significant difference in the progression-free and overall survival according to the radiotherapy status. There was a statistically significant difference in the overall survival according to the chemotherapy status. There was no statistically significant difference in the progression-free and overall survival according to the surgical method. IDH1 and ATRX mutations, p53 overexpression and WT-1 expression alone did not have a significant effect on the prognosis of patients with glioblastoma; however, radiotherapy and chemotherapy had a positive effect on survival.

Effect of Subthalamic Nucleus Stimulation on Pedunculopontine Nucleus Neural Activity.

BACKGROUND: The pedunculopontine nucleus has recently been proposed as an alternative target for deep brain stimulation for the treatment of medically intractable Parkinson's disease. The suggested indication for pedunculopontine nucleus deep brain stimulation is severe and medically intractable axial symptoms such as gait and postural impairment. OBJECTIVE: Our goal in this study was to describe the effects of subthalamic nucleus stimulation on pedunculopontine nucleus electrophysiological activity. METHODS: Fourteen male Wistar rats were divided into a sham stimulation group and an experimental group. In both groups, electrodes were implanted bilaterally into the subthalamic nucleus and into the right pedunculopontine nucleus. Microelectrode recordings were carried out in both groups prior to and during subthalamic nucleus stimulation. RESULTS: Subthalamic nucleus stimulation produced no clear inhibition of neuronal firing in the pedunculopontine nucleus. However, we found that stimulation of the subthalamic nucleus at 60 Hz produces some entrainment of pedunculopontine nucleus neuronal firing and a shift of subthalamic nucleus firing patterns to more tonic and random patterns. These results are consistent with the effects of deep brain stimulation on neuronal activity in the subthalamic nucleus and globus pallidus internus. CONCLUSION: The result of this study provides additional evidence to improve our understanding of the mechanism of subthalamic nucleus-deep brain stimulation, and its physiological consequences.

Reuse of internal pulse generator in cases of infection after deep brain stimulation surgery.

BACKGROUND: Hardware-related infection after deep brain stimulation (DBS) is one of the most serious complications and may need additional interventions. OBJECTIVES: To reuse the internal pulse generator (IPG) after DBS infection and to reduce the economic costs. METHODS: A database of 102 patients who underwent DBS surgery was used in the study. The incidence, clinical characteristics and management of infections while reusing the IPG after DBS-related infection were analyzed and reported. RESULTS: The overall infection rate was 5.9% (6 of 102 patients). Management consisted of total hardware removal followed by intravenous antibiotics. The IPG was at first kept in a solution, then rinsed with water and dried following sterilization with ethylene oxide gas at 38 °C for 18 h. When the treatment of the infection was finished, we reused the IPG and reimplanted the DBS. No hardware-related infection or other complications were observed after reimplantation. CONCLUSIONS: Management of hardware-related infections can be challenging. The medical and economic costs associated with these infections are enormous. The IPG can often be saved in infected patients. Thus, a significant cost burden is eliminated. Properly executed, reuse of IPG should markedly reduce the costs of these devices.

Tentorial Venous Sinuses: A Cadaveric Study.

AIM: To present the configuration of the tentorial venous sinuses, and to determine the optimal incision zone on the tentorium cerebelli. MATERIAL AND METHODS: This study has been completed with 24 autopsied cadavers. For every cadaver, firstly, supratentorial tissues were removed and tentorial measurements were noted, superior part of the tentorial sinuses was captured, and then infratentorial tissues were removed, and all the sinuses were checked and captured. RESULTS: Average age of the studied 24 fresh cadavers was 50 years, wherein 4 were females and 20 were males. Tentorial sinus was presented in 87% of the cases, with 45% medial, 33% lateral, and 22% in the middle third of each tentorium half. CONCLUSION: This study showed the pattern, incidence, location, and distribution of tentorial venous sinuses and tried to find the optimum incision zone by identifying sparse areas for the venous sinuses during transtentorial surgical approaches.

A Novel Perspective to Gamma-Knife Radiosurgery for Solitary Meningiomas: Adaptability of Fast Imaging Employing Steady-State Acquisition/Constructive Interference in Steady-State Magnetic Resonance Imaging.

AIM: T1-weighted contrast-enhanced (T1+C) magnetic resonance imaging (MRI) sequences are usually used for planning meningioma treatment via Gamma-Knife radiosurgery (GKRS). However, practitioners should refrain from using contrast agents because of allergies or other systemic diseases. The fast imaging employing steady-state acquisition (FIESTA) sequence is a high-resolution T2-weighted MRI sequence with a high signal-to-noise ratio that provides good image contrast without using any contrast agent. However, in T1+C sequences, the tumor size appears more prominent due to the contrast agent effect, especially in meningiomas with sinus invasion. Thus, normal anatomical structures may be exposed to radiation. Therefore, we aimed to compare T1+C with FIESTA MRI sequences to protect healthy brain tissue during meningioma treatment with GKRS. MATERIAL AND METHODS: After reviewing the data of 54 patients with solitary meningioma who underwent GKRS between January 2020 and June 2022, demographic characteristics were noted, tumor volumes on T1+C and FIESTA MRI sequences were measured, and sequences were compared. The patients were then divided into two groups according to the presence of invasion to intracranial venous sinuses (groups 1 and 2, respectively). SPSS 11.5 software was used for data analysis, with the level of significance set at 0.05. RESULTS: While no significant age and tumor size differences were observed between groups 1 and 2, sinus invasion was significantly higher among males. Tumor volumes measured in both groups were significantly smaller on FIESTA sequences than on T1+C sequences. CONCLUSION: The T1+C sequence has been the primary imaging method because of meningiomas\' high contrast enhancement feature. However, the T1+C sequence during GKRS planning is an effective imaging method in treating meningiomas; FIESTA sequences can more precisely delineate the tumor border. In this study, we consider that using the FIESTA/CISS sequence MRI for planning meningioma therapy with Gamma-Knife can reduce target volume and prevent irradiation of healthy brain tissue.

The effectiveness of gamma knife radiosurgery for the management of residual high-grade gliomas: A single institutional study.

High-grade gliomas (HGGs) are presently managed via surgical resection, external beam radiation therapy (EBRT), and chemotherapy. Although Gamma Knife radiosurgery (GKRS) is currently used to manage HGGs, it has not been considered standard care. This paper aims to compare the contribution of GKRS to clinical outcomes in patients in which gross total resection (GTR) cannot be achieved. We retrospectively reviewed the data of 99 patients with HGG (World Health Organization (WHO) grade III and IV) from two groups: group 1 consisted of 68 patients for which only EBRT was administered, and group 2 consisted of 31 patients for which EBRT and GKRS were administered. Patient demographic data, the extent of resection, IDH mutation, radiation dosage, progression-free survival (PFS), overall survival (OS), and follow-up time were recorded and compared across groups. The grade III/IV tumor ratio was 10/58 and 10/21 in groups 1 and 2, respectively. In group 2, PFS and OS were higher than in group 1 (P = 0.030 and 0.021). The mean follow-up time was 15.02 ± 11.8 (3-52) and 18.9 ± 98.6 (7-43) months in groups 1 and 2, respectively. In addition to the standard management of HGGs in patients without GTR, boost GKRS during the early postoperative period is beneficial for increasing PFS and OS.

Deep brain stimulation of the pedunculopontine nucleus in a patient with freezing of gait.

CASE PRESENTATION: A 54-year-old male patient presenting probable multiple system atrophy with predominant parkinsonism who underwent bilateral deep brain stimulation (DBS) of the pedunculopontine nucleus (PPN) is presented. The patient had dominant freezing of gait (FOG), levodopa-resistant bradykinesia, and autonomic disturbances, but with a good cognitive condition. METHODS: The patient underwent bilateral DBS of the PPN, which ended with modest benefits. RESULTS AND CONCLUSION: Although he had a short postoperative follow-up (6 months), his neurological status remained stable and PPN DBS provided modest improvements in the gait disorder and freezing episodes. This unusual case suggests that the mesencephalic pedunculopontine region may have a role in locomotor symptoms and the potential to provide a limited improvement in FOG.

The effects of clenbuterol on cerebral vasospasm in an experimental rat model of subarachnoid hemorrhage.

OBJECTIVE: To investigate the possible therapeutic effects of clenbuterol on cerebral vasospasm after subarachnoid hemorrhage (SAH) in rats. METHODS: Eighteen male albino Wistar rats, each weighing 200-250 g, were randomized into three groups; Group 1 (Control group) (n = 6) having no SAH and no treatment; Group 2 (Sham group) (n = 6) having only SAH and Group 3 (Experimental group) (n = 6) having SAH treated with clenbuterol. Group 2 has been accepted as sham group to the experimental group. Experimental SAH was induced using a modified rat double hemorrhage model. Clenbuterol was administered twice daily in 12-hour intervals for three days at a dose of 0,1 mg/kg/day. The luminal diameter of the basilar artery was measured on each section with an optic micrometer by an experienced pathologist blinded to the groups. RESULTS: Mean basilar artery diameters were found to be different between the three groups (p < 0.001). Mean value of Group 2 was significantly lower than that of Group 1 (p < 0.001). While mean value of Group 3 was significantly greater than that of Group 2 (p = 0.001), Groups1 and 3 were found to be similar (p = 0242). CONCLUSION: Clenbuterol has favorable effects in the treatment of rat cerebral vasospasm (CVS). Further investigations are needed to evaluate both molecular effects and to find out effective treatment dose of clenbuterol on CVS.

Effects of the hippocampal deep brain stimulation on cortical epileptic discharges in penicillin - induced epilepsy model in rats.

AIM: Experimental and clinical studies have revealed that hippocampal DBS can control epileptic activity, but the mechanism of action is obscure and optimal stimulation parameters are not clearly defined. The aim was to evaluate the effects of high frequency hippocampal stimulation on cortical epileptic activity in penicillin-induced epilepsy model. MATERIAL AND METHODS: Twenty-five Sprague-Dawley rats were implanted DBS electrodes. In group-1 (n=10) hippocampal DBS was off and in the group-2 (n=10) hippocampal DBS was on (185 Hz, 0.5V, 1V, 2V, and 5V for 60 sec) following penicillin G injection intracortically. In the control group hippocampal DBS was on following 8 µl saline injection intracortically. EEG recordings were obtained before and 15 minutes following penicillin-G injection, and at 10th minutes following each stimulus for analysis in terms of frequency, amplitude, and power spectrum. RESULTS: High frequency hippocampal DBS suppressed the acute penicillin-induced cortical epileptic activity independent from stimulus intensity. In the control group, hippocampal stimulation alone lead only to diffuse slowing of cerebral bioelectrical activity at 5V stimulation. CONCLUSION: Our results revealed that continuous high frequency stimulation of the hippocampus suppressed acute cortical epileptic activity effectively without causing secondary epileptic discharges. These results are important in terms of defining the optimal parameters of hippocampal DBS in patients with epilepsy.

The Supracerebellar Transtentorial Approach in the Prone Position.

The mediobasal temporal region (MTR) is a deep part of the brain covered by eloquent structures. In certain cases, accessing this region is challenging. According to the literature, the supracerebellar transtentorial (SCTT) approach provides safe access to the MTR. Since this approach was introduced by Voigt and Yasargil, many researchers used SCTT in different positions. In particular, the sitting position was the most preferred as it allows the cerebellum to fall away from the tentorium. However, this position has disadvantages such as venous air embolism (VAE), paradoxical air embolism (PAE), and some non ergonomic conditions during surgery. We report two cases with tumors affecting the middle and posterior medial temporal regions. Both patients underwent surgeries in the prone position using the SCTT approach. There were no procedure-related complications. Histopathological results were as follows: psammomatous meningioma in the first case; adenocarcinoma metastasis in the second case. Thus, in this study, the efficacy, feasibility, and safety of accessing the MTR using the SCTT approach in the prone position were demonstrated.

Significant reduction in stereotactic and functional neurosurgical hardware infection after local neomycin/polymyxin application.

OBJECT: Hardware infection is a common occurrence after the implantation of neurostimulation and intrathecal drug delivery devices. The authors investigated whether the application of a neomycin/polymyxin solution directly into the surgical wound decreases the incidence of perioperative infection. METHODS: Data from all stereotactic and functional hardware procedures performed at the Oregon Health & Science University over a 5-year period were reviewed. All patients received systemic antibiotic prophylaxis. For the last 18 months of the 5-year period, wounds were additionally injected with a solution consisting of 40 mg neomycin and 200,000 U polymyxin B sulfate diluted in 10 ml normal saline. The primary outcome measure was infection of the hardware requiring explantation. RESULTS: Six hundred fourteen patients underwent hardware implantation. Among 455 patients receiving only intravenous antibiotics, the infection rate was 5.7%. Only 2 (1.2%) of 159 patients receiving both intravenous and local antibiotics had an infection. The wounds in both of these patients were compromised postoperatively: 1 patient had entered a swimming pool, and the other had undergone a general surgery procedure that exposed the hardware. If these patients are excluded from analysis, the effective infection rate using a combined intravenous and local antibiotic prophylaxis is 0%. There were no complications due to toxicity. CONCLUSIONS: The combination of local neomycin/polymyxin with systemic antibiotic therapy can lead to a significantly lower rate of postoperative infection than when systemic antibiotics are used alone.

Predictors of long-term success after microvascular decompression for trigeminal neuralgia.

OBJECT: Microvascular decompression (MVD) is an effective treatment for trigeminal neuralgia (TN). However, many patients do not experience complete pain relief, and relapse can occur even after an initial excellent result. This study was designed to identify characteristics associated with improved long-term outcome after MVD. METHODS: One hundred seventy-nine consecutive patients who had undergone MVD for TN at the authors' institution were contacted, and 95 were enrolled in the study. Patients provided information about preoperative pain characteristics including preponderance of shock-like (Type 1 TN) or constant (Type 2 TN) pain, preoperative duration, trigger points, anticonvulsant therapy response, memorable onset, and pain-free intervals. Three groups were defined based on outcome: 1) excellent, pain relief without medication; 2) good, mild or intermittent pain controlled with low-dose medication; and 3) poor, severe persistent pain or need for additional surgical treatment. Results Type of TN pain (Type 1 TN vs Type 2 TN) was the only significant predictor of outcome after MVD. RESULTS: were excellent, good, and poor for Type 1 TN versus Type 2 TN patients in 60 versus 25%, 24 versus 39%, and 16 versus 36%, respectively. Among patients with each TN type, there was a significant trend toward better outcome with greater proportional contribution of Type 1 TN (lancinating) symptoms (p < 0.05). CONCLUSIONS: Pain relief after MVD is strongly correlated with the lancinating pain component, and therefore type of TN pain is the best predictor of long-term outcome after MVD. Application of this information should be helpful in the selection of TN patients likely to benefit from MVD.

Radiographic evaluation of trigeminal neurovascular compression in patients with and without trigeminal neuralgia.

OBJECT: Neurovascular compression (NVC) of the trigeminal nerve is associated with trigeminal neuralgia (TN), but also occurs in many patients without facial pain. This study is designed to identify anatomical characteristics of NVC associated with TN. METHODS: Thirty patients with Type 1 TN (intermittent shocklike pain) and 15 patients without facial pain underwent imaging for analysis of 30 trigeminal nerves ipsilateral to TN symptoms, 30 contralateral to TN symptoms, and 30 in asymptomatic patients. Patients underwent 3-T MR imaging including balanced fast-field echo and MR angiography. Images were fused and reconstructed into virtual cisternoscopy images that were evaluated to determine the presence and degree of NVC. Reconstructed coronal images were used to measure nerve diameter and crosssectional area. RESULTS: The incidence of arterial NVC in asymptomatic nerves, nerves contralateral to TN symptoms, and nerves ipsilateral to TN symptoms was 17%, 43%, and 57%, respectively. The difference between symptomatic and asymptomatic nerves was significant regarding the presence of NVC, nerve distortion, and the site of compression (p < 0.001, Fisher exact test). The most significant predictors of TN were compression of the proximal nerve (odds ratio 10.4) and nerve indentation or displacement (odds ratio 4.3). There was a tendency for the development of increasingly severe nerve compression with more advanced patient age across all groups. Decreased nerve size was observed in patients with TN but did not correlate with the presence or extent of NVC. CONCLUSIONS: Trigeminal NVC occurs in asymptomatic patients but is more severe and more proximal in patients with TN. This information may help identify patients who are likely to benefit from microvascular decompression.

Developmental venous anomaly (DVA) with arterial component: a rare cause of intracranial haemorrhage.

INTRODUCTION: To examine the clinical and radiologic findings of patients with developmental venous anomaly (DVA) associated with intracranial haemorrhage but unrelated to cavernoma. METHODS: Computed tomography (CT) was used to obtain intracranial images from seven patients ranging in age from 6 to 51 years. Magnetic resonance imaging (MRI) was then performed on six patients, and two patients were further examined via CT angiography. Finally, digital subtraction angiography (DSA) was performed to confirm the initial diagnosis. RESULTS: CT showed intraparenchymal supratentorial haemorrhage in all patients. The combined imaging modalities eventually confirmed a diagnosis of arterialized DVA in four patients and arterialized DVA associated with arteriovenus malformation (AVM) in three. Two patients were managed symptomatically, two underwent radiosurgery, one underwent surgery, one underwent combined embolisation plus radiosurgery and the remaining patient underwent combined embolisation plus surgery. Two patients died, one as a result of re-bleeding, and the other due to radiation necrosis. The mean follow-up period was 33 months (6 months to 6 years) for the remaining five patients with favourable outcome. CONCLUSION: DVA associated with intraparenchymal haemorrhage, but not related to cavernoma, was confirmed. Though very rare, DVA may present with non-cavernoma-related haemorrhage in the form of arterialized DVA or DVA with AVM.

Comparison of Subthalamic Nucleus vs. Globus Pallidus Interna Deep Brain Stimulation in Terms of Gait and Balance; A Two Year Follow-Up Study.

AIM: To compare the effects of subthalamic nucleus (STN) and globus pallidus interna (GPi) deep brain stimulation (DBS) on the motor outcome, gait and balance function, fall risk (FR), and non-motor symptoms in patients with advanced Parkinson's disease (PD). MATERIAL AND METHODS: We randomized patients with advanced PD with the indication of DBS to undergo either STN or GPi DBS and followed them for 2 years. We collected data at baseline and postoperative 6, 12, and 24 months. We compared changes in the Unified Parkinson's Disease Rating Scale (UPDRS) score, timed gait tests, posturography, non-motor symptom questionnaire (NMSQuest), hospital anxiety and depression (HAD) scale, and levodopa equivalent dose (LED). RESULTS: We enrolled and randomized 12 patients to receive either STN (n = 6) or GPi (n = 6) DBS. Postoperative motor outcomes were significantly improved in both groups (p < 0.05). In both groups, timed gait tests exhibited better performance in mobility; however, patients receiving GPi DBS performed better than those receiving STN DBS in the timed gait tests (p < 0.05). Furthermore, the posturographic evaluation demonstrated a significant elevation in the FR in the STN group (p < 0.05). CONCLUSION: Both STN and GPi DBS are equally effective in alleviating disabling motor complications. However, seemingly, STN DBS could cause more gait and balance problems; hence, a tailored approach seems to be more appropriate in the target selection.

Preoperative visualization of neurovascular anatomy in trigeminal neuralgia.

OBJECT: The authors report on a novel technique to identify neurovascular compression in trigeminal neuralgia (TN). Using 3D reconstructed high-resolution balanced fast-field echo (BFFE) images fused with 3D time-of-flight (TOF) magnetic resonance (MR) angiography and Gd-enhanced 3D spoiled gradient recalled sequence, it is possible to objectively visualize the trigeminal nerve and nearby arteries and veins. METHODS: Magnetic resonance imaging was performed in 18 patients with unilateral TN using 3 sequences: BFFE, 3D TOF angiography, and 3D Gd-enhanced imaging. The images were imported into OsiriX imaging software; after their fusion, a 3D false-color reconstruction was produced using surface rendering. The reconstructed images objectively differentiate nerves and vessels and can be viewed from any angle, including the anticipated surgical approach. RESULTS: Fifteen patients were predicted to have neurovascular compression on the symptomatic side (9 arterial and 6 venous compressions). All patients had a vascular structure that was identical in location and configuration to that predicted on preoperative analysis. The 3 patients without predicted compression underwent surgical exploration because they manifested the classic symptoms. As expected, exploration in 2 of these patients revealed no offending vessel. The third patient had a small vein embedded in the trigeminal nerve that was beyond the resolution of the 3D Gd-enhanced study. CONCLUSIONS: Combining BFFE with MR angiography and Gd-enhanced MR images capitalizes on the advantages of both techniques, enabling MR angiography and contrast-enhanced MR imaging discrimination of vascular structures at BFFE resolution. This results in an unambiguous 3D image that can be used to identify the neurovascular compression and plan the surgical approach.

Seizure outcome following transcortical selective amygdalohippocampectomy in mesial temporal lobe epilepsy.

The aim of this study was to retrospectively determine if patients with medically refractory epilepsy, due to hippocampal sclerosis, who underwent selective amygdalohippocampectomy (SAH) with a transcortical approach experienced improved seizure outcome. Thirty-nine patients with mesial temporal lobe epilepsy and hippocampal sclerosis were included in the study. The mean follow-up was 25.88 +/- 17.69 months. Antiepileptic medication use and seizure frequency were significantly reduced after SAH. After surgery, 32 patients (82.05%) were completely seizure free (Engel class IA), and 2 patients experienced transient memory difficulty. In conclusion, SAH with a transcortical approach can lead to favorable seizure control with a low irreversible complication risk.

Pain relief after cervical ganglionectomy (C2 and C3) for the treatment of medically intractable occipital neuralgia.

Occipital neuralgia (ON) presents a diagnostic challenge because of the wide variety of symptoms, surgical findings, and postsurgical outcomes. Surgical removal of the second (C2) or third (C3) cervical sensory dorsal root ganglion is an option to treat ON. The goal of this study was to evaluate the short-term and the long-term efficacy of these procedures for management of cervical and occipital neuropathic pain. Twenty patients (mean age 48.7 years) were identified who had undergone C2 and/or C3 ganglionectomies for intractable occipital pain and a retrospective chart review undertaken. Patients were interviewed regarding pain relief, pain relief duration, functional status, medication usage and procedure satisfaction, preoperatively, immediately postoperative, and at follow-up (mean 42.5 months). C2, C3 and consecutive ganglionectomies at both levels were performed on 4, 5, and 11 patients, respectively. All patients reported preoperative pain relief following cervical nerve blocks. Average visual analog scale scores were 9.4 preoperatively and 2.6 immediately after procedure. Ninety-five percent of patients reported short-term pain relief (<3 months). In 13 patients (65%), pain returned after an average of 12 months (C2 ganglionectomy) and 8.4 months (C3 ganglionectomy). Long-term results were excellent, moderate and poor in 20, 40 and 40% of patients, respectively. Cervical ganglionectomy offers relief to a majority of patients, immediately after procedure, but the effect is short lived. Nerve blocks are helpful in predicting short-term success, but a positive block result does not necessarily predict long-term benefit and therefore cannot justify surgery by itself. However, since 60% of patients report excellent-moderate results, cervical ganglionectomy continues to have a role in the treatment of intractable ON.

The influence of cervical spinal cord stimulation on induced epileptic discharges in rats.

Spinal cord stimulation (SCS), also known as dorsal column stimulation, is a novel technique used widely in pain surgery. However, its effect on other pathologies such as epileptic disorders is unknown. The aim of this study is to evaluate the influence of electrical epidural stimulation of the upper cervical region on epileptic cortical discharges. The long term goal is to elucidate and evaluate a therapeutic central nervous system (CNS) electrical stimulation methodology to treat epilepsy. Twelve Wistar female rats were randomly divided into two groups. In group 1 (six rats under general anesthesia), C2-3 laminectomies were performed and epidural electrodes were placed to perform SCS. To induce epileptic discharges, 1 ml (200 IU) penicillin G was microinjected into the left somatomotor cortex via left stereotactic parietal craniotomies, 0.01 to 0.1 mA at 2 Hz was used to stimulate the spinal cord. In group 2 (the control group, six rats under general anesthesia), C2-3 laminectomies were performed without electrode placement and epileptic discharges were induced with penicillin G microinjections, as described above. Both groups were monitored with digital electroencencephalography (EEG) for 70 min in seven stages and recordings analyzed with power spectral analysis. Spinal cord stimulation decreased penicillin-induced median values of epileptic discharges. Epileptic wave frequencies decreased significantly with increasing intensities of SCS. The results of this study suggest that SCS used for drug resistant epilepsies may be a viable alternative treatment modal.