Psychosocial outcomes six months after epilepsy surgery: A perspective on coping strategies.

OBJECTIVE: Epilepsy negatively affects the social functioning of patients. Epilepsy surgery is a treatment with superior rates of seizure freedom. The psychosocial outcomes after epilepsy surgery depend on several factors, including the patient's coping style. It is important to identify the patients who are at risk of experiencing psychosocial difficulties after epilepsy surgery and consult them for psychiatric interventions. This study aimed to assess changes in social adaptation, felt stigma, self-esteem, and self-efficacy after epilepsy surgery, and the effect of coping strategies, sociodemographic and epilepsy-related variables, and post-surgical seizure outcomes on these results. METHODS: Thirty adult patients with temporal lobe epilepsy who were candidates for surgery were included in the study (mean age: 33.07, mean seizure onset age: 17.2, mean duration of epilepsy: 15.8). The patients were assessed before and 6 months after epilepsy surgery using the Epilepsy Self-Efficacy Scale, Social Adaptation Self-Evaluation Scale, Rosenberg Self-Esteem Scale, Felt Stigma Scale, and Coping Orientation to Problems Experienced Inventory. RESULTS: The patients' self-efficacy levels were increased after surgery (p = 0.005). Postsurgical social adaptation levels were associated with higher positive reinterpretation and growth, active coping, and planning (p = 0.016, p = 0.005, p = 0.002, respectively). Postsurgical self-efficacy levels were positively associated with active coping and planning (p = 0.003, p = 0.035, respectively). Postsurgical self-esteem (p = 0.012, p = 0.049, p = 0.034, respectively) and stigma (p = 0.029, p = 0.014, p = 0.027, respectively) were negatively associated with positive reinterpretation and growth, active coping, and planning. Furthermore, being employed presurgical period was associated with better postsurgical social adaptation (p = 0.004). CONCLUSIONS: The psychosocial outcomes after epilepsy surgery depend not only on seizure outcomes. Understanding the factors beyond seizure freedom, allows healthcare professionals to have a pivotal role in exploring and managing patients' expectations, fostering a more comprehensive and realistic dialogue about potential outcomes. Considering employed patients had better psychosocial outcomes, we suggest patients' families, healthcare professionals, and epilepsy support organizations should work collaboratively to support people with epilepsy in terms of providing job opportunities.

The Relationship Between Inflammatory Processes and Apoptosis in Lumbar Disc Degeneration.

OBJECTIVE: Degenerative Disc Disease (DDD) is a common health problem in the population. There are recent studies focusing on relationship between DDD and immunological factors. However, there is still a lack of data on the role of apoptosis in DDD pathophysiology. Therefore, we aimed to investigate the relationship between Modic-type changes and the apoptosis in DDD. MATERIALS AND METHODS: Ninety adult male patients who presented with low back and/or radicular pain and were operated on due to lumbar disc herniation were included. Three groups were formed based on Modic type degeneration observed on magnetic resonance imaging. Specific parameters involved in the intrinsic and extrinsic pathways of apoptosis were assessed in excised disc materials using the enzyme-linked immunosorbent assay method. RESULTS: All three groups formed according to Modic degeneration types were homogenous in all variances. Cytochrome-C was significantly decreased only in the Modic type-3 group, whereas Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor-1, B-Cell Lymphoma-2 (Bcl-2) Homologous Antagonist Killer-1, Direct Inhibitor of Apoptosis-Binding Protein with Low Pi, and Bcl-2 Associated X Apoptosis Regulator levels were significantly different in both Modic type-2 and -3 groups. However, BH3 interacting domain death agonist and Bcl-2 levels were similar across all groups. CONCLUSIONS: In conclusion, this study suggests that Direct Inhibitor of Apoptosis-Binding Protein with Low Pi, cytochrome - c, Bcl-2 Associated X Apoptosis Regulator, Bcl-2 Homologous Antagonist Killer-1, and Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor-1proteins play important roles in the development and progression of DDD and are correlated with Modic types. Further studies are needed to explore the potential therapeutic role of inhibiting these apoptotic proteins in DDD.

Functional hemispheric disconnection procedures for chronic epilepsy: history, indications, techniques, complications and current practice in Europe. A consensus statement on behalf of the EANS functional neurosurgery section.

Introduction: The surgical procedure for severe, drug-resistant, unilateral hemispheric epilepsy is challenging. Over the last decades the surgical landscape for hemispheric disconnection procedures changed from anatomical hemispherectomy to functional hemispherotomy with a reduction of complications and stable good seizure outcome. Here, a task force of European epilepsy surgeons prepared, on behalf of the EANS Section for Functional Neurosurgery, a consensus statement on different aspects of the hemispheric disconnection procedure. Research question: To determine history, indication, timing, techniques, complications and current practice in Europe for hemispheric disconnection procedures in drug-resistant epilepsy. Material and methods: Relevant literature on the topic was collected by a literature search based on the PRISMA 2020 guidelines. Results: A comprehensive overview on the historical development of hemispheric disconnection procedures for epilepsy is presented, while discussing indications, timing, surgical techniques and complications. Current practice for this procedure in European epilepsy surgery centers is provided. At present, our knowledge of long-term seizure outcomes primarily stems from open surgical disconnection procedures. Although minimal invasive surgical techniques in epilepsy are rapidly developing and reported in case reports or small case series, long-term seizure outcome remain uncertain and needs to be reported. Discussion and conclusion: This is the first paper presenting a European consensus statement regarding history, indications, techniques and complications of hemispheric disconnection procedures for different causes of chronic, drug-resistant epilepsy. Furthermore, it serves as the pioneering document to report a comprehensive overview of the current surgical practices regarding this type of surgery employed in renowned epilepsy surgery centers across Europe.

Expansion of the Subcutaneous Compartment by Umbilicus Resection for Intrathecal Pump Placement: The "Karagoz-Hacivat Technique".

BACKGROUND AND OBJECTIVES: Intrathecal baclofen (ITB) for severe spasticity can encounter complications such as wound dehiscence and ulcers because of elevated intracompartmental pressure within the abdominal subcutaneous and subfascial pocket housing the pump. We propose an innovative technique to manage ITB wound ulcers. METHODS: Resecting the umbilicus create a more spacious and less tension-prone pocket for the ITB pump. RESULTS: Between 2015 and 2023, we implanted ITB pumps in 65 patients. Among them, 5 patients presented with skin ulcer or dehiscence underwent surgery using the novel technique. Postoperative follow-up revealed successful wound healing, with no further wound-related complications. CONCLUSION: The proposed technique provides effective and practical solution to wound and skin complications related to ITB pump. Moreover, it may serve as a viable preemptive strategy during the initial implantation of the ITB pump in selected patients.

Imaging findings of intraventricular pilocytic astrocytoma.

OBJECTIVE: The aim of this study is to present the clinical and imaging findings of 16 patients with intraventricular pilocytic astrocytomas (PAs). METHODS: 16 patients with histopathological diagnosis of intraventricular PA between February 2016 and January 2022 were evaluated retrospectively. Imaging and clinical findings of the patients, as well as apparent diffusion coefficient (ADC) measurements were analyzed. RESULTS: Of 16 patients, 8 (%50) were male and 8 (%50) were female. The mean age of the patients was 20.8 years (2-44 years range). The most common symptoms in the patients were headache and ataxia. The mean long-axis size of lesions was found to be 48.19 ± 21.59 (range, 15-92 mm). 9 out of 16 lesions (56.2%) were located in the fourth ventricle. The majority of the lesions were iso-hypointense in T1W and hyperintense in T2W images. The mean ADC value of PAs was 1.57 × 10-3 ± 0.2 mm2/s, while the mean thalamic ADC and white matter ADC values were found to be 0.78 × 10-3 ± 0.04 and 0.76 × 10-3 ± 0.06 mm2/s, respectively. There was a statistically significant difference between the ADC values obtained from the solid components of the lesions and the thalami/white matter (p < 0.001). CONCLUSION: PAs often originate from midline structures, however, they can also be located intraventricularly. Although intraventricular PAs are frequently seen in pediatric population, it should be kept in mind that they can also be seen in adults, albeit rarely. ADVANCES IN KNOWLEDGE: PA should be considered in the differential diagnosis of intraventricular neoplasms in case of high ADC values.

Vitamin D receptor regulates transcription of mitochondrial DNA and directly interacts with mitochondrial DNA and TFAM.

Vitamin D receptor (VDR) is an essential transcription factor (TF) synthesized in different cell types. We hypothesized that VDR might also act as a mitochondrial TF. We conducted the experiments in primary cortical neurons, PC12, HEK293T, SH-SY5Y cell lines, human peripheral blood mononuclear cells (PBMC) and human brain. We showed that vitamin D/VDR affects the expression of mitochondrial DNA (mtDNA) encoded oxidative phosphorylation (OXPHOS) subunits. We observed the co-localization of VDR with mitochondria and the mtDNA with confocal microscopy. mtDNA-chromatin-immunoprecipitation and electrophoretic mobility shift assays indicated that VDR was able to bind to the mtDNA D-loop site in several locations, with a consensus sequence "MMHKCA." We also reported the possible interaction between VDR and mitochondrial transcription factor A (TFAM) and their binding sites located in close proximity in mtDNA. Consequently, our results showed for the first time that VDR was able to bind and regulate mtDNA transcription and interact with TFAM even in the human brain. These results not only revealed a novel function of VDR, but also showed that VDR is indispensable for energy demanded cells.

Outcome Predictors of Lesional Posterior Cortex Epilepsy Surgery.

BACKGROUND: Lesional posterior cortex epilepsy (PCE) is often drug resistant and may benefit from surgical intervention. In this study, we aimed to identify potential predictive factors associated with seizure recurrence after epilepsy surgery in lesional PCE. METHODS: We retrospectively reviewed patients with PCE who underwent surgery between 1998 and 2021. They were divided into 2 groups according to seizure outcome; the seizure-free group (group 1) and the non-seizure-free group (group 2). The relationship among clinical factors, electroencephalography (EEG) or cranial magnetic resonance imaging findings, disease, and seizure outcome was investigated. RESULTS: A total of 60 patients, with a mean age of 27.26 ± 12.35 years (range, 9-61 years), were included in the study. There were 31 patients (51.66%) in group 1 (Engel class I) and 29 patients (48.33%) in group 2 (13 [21.66%], 10 [16.66%], and 6 [10%] patients in Engel class II, III, and IV, respectively), with a mean follow-up of 8.95 ± 6.96 years (range, 1-24 years). No difference was observed regarding age, gender, age at seizure onset, operation type, treatment gap, and presence of bilateral lesions between the groups (P > 0.05). However, bilateral findings on interictal EEG and gliosis as the underlying disease were predictors of seizure recurrence (P < 0.05). CONCLUSIONS: More than half of the patients (including 2 with bilateral magnetic resonance imaging lesions) were seizure free at long-term follow-up. However, patients with bilateral findings on interictal EEG and gliosis were more likely to have recurrent seizures after surgery. Because lesional PCE is almost always drug resistant and has a potential for favorable outcomes, epilepsy surgery should be considered early.

Vagus Nerve Stimulation in Intractable Epilepsy.

AIM: To investigate and compare the efficacy and safety of vagus nerve stimulation (VNS) therapy in different types of epilepsy. MATERIAL AND METHODS: Patients, who were implanted with VNS between the years 2005 and 2020, were retrospectively included in the study. Age, gender, age at seizure onset, epilepsy types, VNS implantation year, replacement year, pre and post-VNS seizure frequency, number of responders, number of antiseizure medication and adverse events were recorded. RESULTS: In total, 41 patients were included in the study. The number of patients with focal epilepsy was 21 (51.2%). 10 patients (24.4%) had generalized epilepsy and 10 patients (24.4%) had ?combined generalized and focal epilepsy? (Lennox-Gastaut, Dravet syndrome). The Pre-VNS median seizure frequency was 1.5/day in the focal group, 0.6/day in the generalized group and 6/day in the combined group. Seizure frequencies dropped to 0.3/day in the focal group, 0.2/day in the generalized group and 3.0/day in the combined group at the 12th month after VNS (p < 0.001, p=0.004, p < 0.001). The response rate was found to be 68.3% at the 12th month after VNS. The number of antiseizure medications was decreased from 3.6/day to 3.1/day at the 12th months after VNS (p < 0.001). Two patients? (4.9%) VNS therapy was discontinued due to adverse events. CONCLUSION: The study indicates that VNS therapy is safe and effective in focal, generalized and combined epilepsy types. Despite having a low seizure freedom rate, VNS is a good alternative treatment option for patients who for any reason are not candidates for resective surgery.

Factors Affecting Seizure Outcomes After Surgery for Cavernoma Related Epilepsy.

AIM: To present one of the largest retrospective cavernoma related epilepsy (CRE) studies which include divergent supratentorial locations operated and followed up at least 2 years. We also investigated the factors affecting the seizure outcome. MATERIAL AND METHODS: This study includes a total of 56 patients with drug-responsive (n=40) and drug-resistant (n=16) CRE who underwent resective surgery. Age at seizure onset, age at surgery, gender, duration of epilepsy, seizure frequencies/type before and after treatment, EEG and brain MRI findings, prescribed AEDs, preoperative and post-operative neurological status, histopathological diagnosis, post-operative seizure outcomes and surgical information were documented. RESULTS: The average follow-up period was 69.6 months (range 24-216 months). The seizure outcome was assessed according to Engel?s classification at the last follow-up. Engel class I was achieved in 53 patients (95%); there was one patient at class II and two patients at class III. All patients in the drug-responsive group were at Engel class I after the surgery, while all patients at Engel classes II and III were in the drug-resistant patient group. This clearly shows that there were better outcomes in DRP group (p < 0.01). Neither the locations of cavernomas nor the duration of epilepsy had any impact on seizure outcome (p > 0.05). CONCLUSION: An earlier surgical intervention may prevent the patients from becoming drug-resistant such that their chances of being seizure free after surgery increase.

A novel insight into differential expression profiles of sporadic cerebral cavernous malformation patients with different symptoms.

Cerebral cavernous malformation (CCM) is a vascular lesion of the central nervous system that may lead to distinct symptoms among patients including cerebral hemorrhages, epileptic seizures, focal neurologic deficits, and/or headaches. Disease-related mutations were identified previously in one of the three CCM genes: CCM1, CCM2, and CCM3. However, the rate of these mutations in sporadic cases is relatively low, and new studies report that mutations in CCM genes may not be sufficient to initiate the lesions. Despite the growing body of research on CCM, the underlying molecular mechanism has remained largely elusive. In order to provide a novel insight considering the specific manifested symptoms, CCM patients were classified into two groups (as Epilepsy and Hemorrhage). Since the studied patients experience various symptoms, we hypothesized that the underlying cause for the disease may also differ between those groups. To this end, the respective transcriptomes were compared to the transcriptomes of the control brain tissues and among each other. This resulted into the identification of the differentially expressed coding genes and the delineation of the corresponding differential expression profile for each comparison. Notably, some of those differentially expressed genes were previously implicated in epilepsy, cell structure formation, and cell metabolism. However, no CCM1-3 gene deregulation was detected. Interestingly, we observed that when compared to the normal controls, the expression of some identified genes was only significantly altered either in Epilepsy (EGLN1, ELAVL4, and NFE2l2) or Hemorrhage (USP22, EYA1, SIX1, OAS3, SRMS) groups. To the best of our knowledge, this is the first such effort focusing on CCM patients with epileptic and hemorrhagic symptoms with the purpose of uncovering the potential CCM-related genes. It is also the first report that presents a gene expression dataset on Turkish CCM patients. The results suggest that the new candidate genes should be explored to further elucidate the CCM pathology. Overall, this work constitutes a step towards the identification of novel potential genetic targets for the development of possible future therapies.

Ultrastructural investigation of synaptic alterations in the rat hippocampus after irradiation and hyperthermia.

This study aimed to investigate ultrastructural synaptic alterations in rat hippocampus after in utero exposure to irradiation (IR) and postnatal exposure to hyperthermia (HT). There were four groups in each of the time points (3rd and 6th months). IR group: Pregnant rats were exposed to radiation on the 17th gestational day. HT group: Hyperthermia was applied to the rat pups on the 10th day after their birth. IR+HT group: Both IR and HT were applied at the same time periods. Control group: No IR or HT was applied. Rat pups were sacrificed after 3 and 6 months. Thin sections from the dentate gyrus (DG) and the CA3 of hippocampus were evaluated for synapse numbers by electron microscopy. Synapses were counted, and statistical analysis was performed. Abnormalities in myelin sheath, mossy terminals and neuropil were observed in the CA3 and DG of all groups. The synapses in the CA3 region were significantly increased in the IR-3rd month, IR-6th month, and IR+HT-3rd month groups vs control group. Synapses were significantly increased in the DG of HT-3rd month group. A trend for an increase in synapse numbers was seen in the CA3 and DG. Increased number of synapses in the rat hippocampus may be due to mossy fiber sprouting, possibly caused by in utero irradiation and/or postnatal hyperthermia.

Evaluation of Ideal Extent of Corpus Callosotomy Based on the Location of Intracallosal Motor Fibers.

BACKGROUND: The corpus callosotomy (CCT) has been reported as an effective procedure to alleviate drop attacks. However, the extent of CCT remains debatable. Classical studies suggest that motor fibers traverse mainly through the anterior half of the corpus callosum (CC), although recent diffusion tensor imaging studies described that motor fibers crossed the CC in a more posterior location, emphasizing the posterior midbody and the isthmus. METHODS: Cortical and subcortical structures were examined in 30 hemispheres prepared for white matter fiber dissection. Dissections were carried out under surgical magnification to trace fibers originating from the primary motor cortex and their course through the CC. The distance of the most anterior and posterior motor fibers to the tip of the genu were measured, and the extent of CCT enabling disconnection of all motor fibers was calculated. RESULTS: Motor fibers coursed through the posterior half of the CC in the majority of hemispheres, mainly locating in posterior midbody and the isthmus. Callosal fibers should be interrupted to an average of 61% ± 0.07% point of the CC to reach the anterior limit of motor fibers and to an average of 69% ± 0.07% point to include posterior limit of motor fibers. Motor fibers were extending until the posterior one third of the CC in 22 specimens. CONCLUSIONS: Anterior-half CCT did not include all motor fibers in any specimen. Anterior two thirds CCT disrupted all motor fibers in one fourth of the cases. Our findings suggest that an ideal CCT should extend to the posterior midbody and isthmus of the CC.

Immediate versus delayed primary repair of the sciatic nerve in a nerve transaction model in rats.

BACKGROUND: The debate continues concerning surgical timing in a peripheral nerve injury. This study aims to evaluate the result of immediate versus delayed primary (after seven days) repair of peripheral nerve injury. METHODS: In this study, Wistar rats were divided into four groups as follows: The nerve was sharply transected in Group 1, 2 and 4. It was immediately sutured in Group 1 and sutured seven days later in Group 2, and it was not sutured in Group 4. In Group 3, the left sciatic nerve was only explored. Eight weeks later, tissue samples were extracted from the injured nerve area. Both gastrocnemius muscles were weighed. The nerve samples were examined for axon degeneration. Myelin vacuolization, axon irregularity, and edema/inflammation parameters were evaluated. RESULTS: There were not any significant differences in the score of axon degeneration and the weight of the gastrocnemius muscle between the immediate and delayed primary repair groups. However, these parameters were significantly better in both repair groups than to be in the control group and significantly worse than to be in the sham-operated group. CONCLUSION: To delay the repair about one week did not affect the histological results and weight of the muscle that was innervated by the sectioned nerve comparing to be in the immediate repair in a sciatic nerve transaction model in rats.

C6-T1 Intradural Extramedullary Ventral Meningeal Melanocytoma Resected Via Anterior Corpectomy with Reconstruction.

BACKGROUND: Melanocytic lesions of the nervous system are thought to arise from leptomeningeal melanocytes, which are derived from neural crest and include diffuse melanocytosis, melanocytomas, and malignant melanomas. Meningeal melanocytomas are extremely rare benign lesions. The usual treatment of intradural extramedullary melanocytomas involves surgical removal through a posterior approach using a laminectomy or laminotomy. CASE DESCRIPTION: We present a 30-year-old female harboring a C6-T1 ventrally located intradural extramedullary lesion compressing the cord anteriorly. The lesion was totally resected via an anterior approach with oblique corpectomy even if the usual treatment involves surgical removal through a posterior approach using a laminectomy or laminotomy. CONCLUSIONS: There is no evidence of recurrence at 4-year follow-up records of the patient. We discuss the surgical approach of these rare lesions.

Surgical management of spinal intramedullary tumors: Ten-year experience in a single institution.

Despite their rare occurrence, intramedullary spinal cord tumors can cause considerable morbidity and mortality without treatment. Timing of surgery, extent of resection and selection of favorable treatment option are important considerations for a good surgical outcome. In this clinical study, we report our patient series and convey our treatment strategy. We retrospectively reviewed 91 patients with primary intramedullary spinal cord tumors who underwent microsurgical resection at our institution between 2008 and 2018. Data were collected consisting of age, sex, location and histology of tumor, extent of resection, presenting symptoms and neurological outcomes. Modified McCormick Scale was used to assess neurological status of patients. 47 female and 44 male patients were followed-up for a mean period of 35.7 months. The most frequent pathological diagnosis was ependymoma in 56 patients, followed by astrocytoma in 21 and hemangioblastoma in 5 patients. The rest of the tumors consisted of 3 cavernomas, 3 mature cystic teratomas, 2 PNET, one epidermoid tumor. Gross total resection was achieved in 67 patients, while subtotal resection and biopsy was performed in 15 and 9 respectively. The most commonly involved localization was cervical (n = 39), followed by thoracic region (n = 24). Despite immediate postoperative worsening of neurological status, a great number of patients improved at the last follow-up. Gross total resection remains the primary goal of treatment while adjuvant radiation and/or chemotherapy may be alternative options for high grade tumors. Preoperative neurological status was the most important and the strongest predictor of functional outcome.

Machine learning-based quantitative texture analysis of conventional MRI combined with ADC maps for assessment of IDH1 mutation in high-grade gliomas.

PURPOSE: To assess the performance of texture analysis of conventional magnetic resonance imaging (MRI) and apparent diffusion coefficient (ADC) maps in predicting IDH1 status in high-grade gliomas (HGG). MATERIALS AND METHODS: A total of 142 patients with HGG were included in the study. IDH1 mutation was present in 48 of 142 HGG (33.8%). Patients were randomly divided into the training cohort (n = 96) and the validation cohort (n = 46). Texture features were extracted via regions of interest on axial T2WI FLAIR, post-contrast T1WI, and ADC maps covering the whole volume of the tumors. The training cohort was used to train the random forest classifier, and the diagnostic performance of the pre-trained model was tested on the validation cohort. RESULTS: The random forest model of conventional MRI sequences and ADC images achieved diagnostic accuracy of 82.2% and 80.4% in predicting IDH1 status in the validation cohorts, respectively. The combined model of T2WI FLAIR, post-contrast T1WI, and ADC images exhibited the highest diagnostic accuracy equating 86.94% in the validation cohort. CONCLUSION: Texture analysis of conventional MRI sequences enhanced by ML analysis can accurately predict the IDH1 status of HGG. Adding textural analysis of ADC maps to conventional MRI results in incremental diagnostic performance.

Spinal Vascular Malformations: Treatment and Outcome.

BACKGROUND: Vascular malformations of the spinal cord are a rare and complex clinical entity and can lead to severe morbidity with progressive spinal cord symptoms if not treated properly. In early stages, the disease is characterized by slowly progressive, nonspecific symptoms, such as gait disturbance, paresthesia, diffuse sensory symptoms, and radicular pain; in the late stages, bowel and bladder incontinence, erectile dysfunction, and urinary retention may develop. In recent decades, understanding and treatment of spinal vascular malformations have improved with the evolution of diagnostic tools and treatment modalities; however, it is still difficult to manage these cases because of the complexity of the pathology. The aims of this study were to present the long-term outcomes of our patients and to discuss the optimal management strategies. METHODS: We reviewed the records of 78 patients with spinal vascular malformations and performed a retrospective, single-center case series evaluating initial occlusion, recanalization, retreatment, and neurologic status of patients with dural arteriovenous fistulas, perimedullary arteriovenous fistulas, arteriovenous malformations, and extradural arteriovenous fistulas who had undergone embolization and/or surgery. RESULTS: No mortality was observed. Complete obliteration was achieved in 76 patients (97.4%). CONCLUSIONS: Both endovascular and surgical treatment of spinal vascular malformations resulted in significant long-term recovery from myelopathic symptoms and improvement in quality of life for most patients.

An Exceptional Neurosurgical Presentation of a Patient with Osteopetrosis.

BACKGROUND: Osteopetrosis (OP) is a varied clinical condition caused by malfunction or insufficient development of osteoclasts, or both. Neurologic findings can occur because of osteopetrotic conditions restricting neural foramina through which the spinal cord, cranial nerves, or major vascular structures traverse the skull. Renal tubular acidosis (RTA) is a well-documented condition with OP. However, Chiari I malformation is rarely reported concomitantly with OP. CASE DESCRIPTION: We present a patient with a known RTA who was admitted with a rapid progressive tetraparesis within 24 hours. Clinical and radiologic evaluation of the patient revealed OP with RTA together with Chiari I malformation and holocord hydromyelia. Management of the patient was started with correction of severe hypokalemia (K: 1.4 mEq/L), which resulted in dramatic improvement in tetraparesis. Two days later, a posterior fossa bone decompression with ventriculoperitoneal shunt placement during the same session led to prominent decrease in size of the ventricles and the hydromyelia on long-term follow-up. CONCLUSIONS: Patients with OP can exhibit many clinical conditions. However, our case involved an unusual and rapid progressive tetraparesis, which could confuse the management as necessitating an emergent posterior fossa decompression. Stabilizing the metabolic status of the patient facilitated elective surgery, which further improved patient's neurologic findings and diminished hydromyelia on long-term follow-up.

Dysembryoplastic neuroepithelial tumours: clinical, radiological, pathological features and outcome.

OBJECT: To analyse the clinical, imaging and histopathological data of patients who were diagnosed to have Dysembrioplastic Neuroepithelial Tumour (DNET) and underwent surgery between 1995-2015. MATERIALS AND METHODS: Age at seizure onset, age at surgery, gender, disease duration, seizure outcome of 44 patients were analysed together with Magnetic Resonance Imaging (MRI) of 21 patients. MRI types were classified as type 1 (cystic/polycystic-like, well-delineated, strongly hypointense T1), type 2 (nodularlike,heterogeneous), type 3 (dysplastic-like, iso/hyposignal T1, poor delineation, gray-white matter blurring). RESULTS: Histopathological classification revealed simple form in 19, complex in 14 and non-specific in 11 patients. Lobar distribution of the lesions was as follows: 21 Temporal (47.7%), 12 parietal (27.3%), 8 frontal (18.2%) and 3 occipital (6.8%). Type 1 MRI was observed in 10, type 2 was in 7, and type 3 in 4 patients on radiological evaluation. All cases with type 1 MRI corresponded to either simple or complex forms and all cases with type 3 MRI corresponded to nonspecific form. The histopathological distribution of cases with type 2 MRI was 4 as non-specific, 2 as simple, 1 as complex. There was no significant difference in the age of onset, age at operation and duration of epilepsy between the patients with different MRI subtypes. The majority of patients (N:36) had Engel I outcome (81,8%). In groups with Engel II and III outcome, duration of epilepsy was significantly higher (p:0,014) and simple form of DNET has significantly higher seizure freedom after surgery compared to complex and nonspecific forms of DNET (p:0,002). CONCLUSION: Patients with DNET constitute a group with favorable outcomes after epilepsy surgery especially with early referral to surgery. Longer duration of epilepsy was associated with worse seizure outcome for DNET patients. There was significant correlation between radiological and histopathological types of DNET especially in type 1 and 3.