MRI-based Neuropathy Score Reporting And Data System (NS-RADS): multi-institutional wider-experience usability study of peripheral neuropathy conditions among 32 radiology readers.

OBJECTIVE: To determine the inter-reader reliability and diagnostic performance of classification and severity scales of Neuropathy Score Reporting And Data System (NS-RADS) among readers of differing experience levels after limited teaching of the scoring system. METHODS: This is a multi-institutional, cross-sectional, retrospective study of MRI cases of proven peripheral neuropathy (PN) conditions. Thirty-two radiology readers with varying experience levels were recruited from different institutions. Each reader attended and received a structured presentation that described the NS-RADS classification system containing examples and reviewed published articles on this subject. The readers were then asked to perform NS-RADS scoring with recording of category, subcategory, and most likely diagnosis. Inter-reader agreements were evaluated by Conger's kappa and diagnostic accuracy was calculated for each reader as percent correct diagnosis. A linear mixed model was used to estimate and compare accuracy between trainees and attendings. RESULTS: Across all readers, agreement was good for NS-RADS category and moderate for subcategory. Inter-reader agreement of trainees was comparable to attendings (0.65 vs 0.65). Reader accuracy for attendings was 75% (95% CI 73%, 77%), slightly higher than for trainees (71% (69%, 72%), p = 0.0006) for nerves and comparable for muscles (attendings, 87.5% (95% CI 86.1-88.8%) and trainees, 86.6% (95% CI 85.2-87.9%), p = 0.4). NS-RADS accuracy was also higher than average accuracy for the most plausible diagnosis for attending radiologists at 67% (95% CI 63%, 71%) and for trainees at 65% (95% CI 60%, 69%) (p = 0.036). CONCLUSION: Non-expert radiologists interpreted PN conditions with good accuracy and moderate-to-good inter-reader reliability using the NS-RADS scoring system. CLINICAL RELEVANCE STATEMENT: The Neuropathy Score Reporting And Data System (NS-RADS) is an accurate and reliable MRI-based image scoring system for practical use for the diagnosis and grading of severity of peripheral neuromuscular disorders by both experienced and general radiologists. KEY POINTS: • The Neuropathy Score Reporting And Data System (NS-RADS) can be used effectively by non-expert radiologists to categorize peripheral neuropathy. • Across 32 different experience-level readers, the agreement was good for NS-RADS category and moderate for NS-RADS subcategory. • NS-RADS accuracy was higher than the average accuracy for the most plausible diagnosis for both attending radiologists and trainees (at 75%, 71% and 65%, 65%, respectively).

Is intraoperative electrocorticography (ECoG) for long-term epilepsy-associated tumors (LEATs) more useful in children?-A Randomized Controlled Trial.

OBJECTIVES: The utility of intraoperative electrocorticography (ECoG)-guided resective surgery for pediatric long-term epilepsy-associated tumors (LEATs) with antiseizure medication (ASM) resistant epilepsy is not supported by robust evidence. As epilepsy networks and their ramifications are different in children from those in adults, the impact of intraoperative ECoG-based tailored resections in predicting prognosis and influencing outcomes may also differ. We evaluated this hypothesis by comparing the outcomes of resections with and without the use of ECoG in children and adults by a randomized study. METHODS: From June 2020 to January 2022, 42 patients (17 children and 25 adults) with LEATs and antiseizure medication (ASM)-resistant epilepsy were randomly assigned to one of the 2 groups (ECoG or no ECoG), prior to surgical resection. The 'no ECoG' arm underwent gross total lesion resection (GTR) without ECoG guidance and the ECoG arm underwent GTR with ECoG guidance and further additional tailored resections, as necessary. Factors evaluated were tumor location, size, lateralization, seizure duration, preoperative antiepileptic drug therapy, pre- and postresection ECoG patterns and tumor histology. Postoperative Engel score and adverse event rates were compared in the pediatric and adult groups of both arms. Eloquent cortex lesions and re-explorations were excluded to avoid confounders. RESULTS: Forty-two patients were included in the study of which 17 patients were in the pediatric cohort (age < 18 years) and 25 in the adult cohort. The mean age in the pediatric group was 11.11 years (SD 4.72) and in the adult group was 29.56 years (SD 9.29). The mean duration of epilepsy was 9.7 years (SD 4.8) in the pediatric group and 10.96 (SD 8.8) in the adult group. The ECoG arm of LEAT resections had 23 patients (9 children and 14 adults) and the non-ECoG arm had 19 patients (8 children and 11 adults). Three children and 3 adults from the ECoG group further underwent ECoG-guided tailored resections (average 1.33 additional tailored resections/per patient.).The histology of the tailored resection specimen was unremarkable in 3/6 (50%).Overall, the commonest histology in both groups was ganglioglioma and the temporal lobe, the commonest site of the lesion. 88.23% of pediatric cases (n = 15/17) had an excellent outcome (Engel Ia) following resection, compared to 84% of adult cases (n = 21/25) at a mean duration of follow-up of 25.76 months in children and 26.72 months in adults (p = 0.405).There was no significant difference in seizure outcomes between the ECoG and no ECoG groups both in children and adults, respectively (p > 0.05). Additional tailored resection did not offer any seizure outcome benefit when compared to the non-tailored resections. CONCLUSIONS: The use of intraoperative electrocorticography in LEATs did not contribute to postoperative seizure outcome benefit in children and adults. No additional advantage or utility was offered by ECoG in children when compared to its use in adults. ECoG-guided additional tailored resections did not offer any additional seizure outcome benefit both in children and adults.

Utility of balanced steady-state field precession sequence in the evaluation of retinal and subdural hemorrhages in patients with abusive head trauma.

Abusive head trauma is the leading cause of physical child abuse deaths in children under 5 years of age in the United States. To evaluate suspected child abuse, radiologic studies are typically the first to identify hallmark findings of abusive head trauma including intracranial hemorrhage, cerebral edema, and ischemic injury. Prompt evaluation and diagnosis are necessary as findings may change rapidly. Current imaging recommendations include brain magnetic resonance imaging with the addition of a susceptibility weighted imaging (SWI) sequence which can detect additional findings that suggest abusive head trauma including cortical venous injury and retinal hemorrhages. However, SWI is limited due to blooming artifacts and artifacts from the adjacent skull vault or retroorbital fat, which can affect the evaluation of retinal, subdural, and subarachnoid hemorrhages. This work explores the utility of the high-resolution, heavily T2 weighted balanced steady-state field precession (bSSFP) sequence to identify and characterize retinal hemorrhage and cerebral cortical venous injury in children with abusive head trauma. The bSSFP sequence provides distinct anatomical images to improve the identification of retinal hemorrhage and cortical venous injury.

Venous injury in pediatric abusive head trauma: a pictorial review.

Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. An intracranial pathology can exist even in the setting of a normal physical exam. A delay in the diagnosis of AHT can have serious life-threatening consequences for the child and increases the potential the child will be abused again. In this article, we review the traumatic subdural hematoma as well as various morpho-structural patterns of shearing injuries and thrombosis of intracranial bridging veins. This work serves as a summary of patterns of imaging features of intracranial venous injury in AHT, as described in the literature, to facilitate familiarity and early detection of abusive head trauma in the pediatric population. Essentially, in AHT there is a traumatic injury to the bridging vein with either partial or complete tear. This can secondarily result in thrombosis at the terminal end of the bridging vein with blood clots adjacent to the bridging vein.

Pediatric interventional radiology workforce in North America: a descriptive analysis of demographics, educational backgrounds and scholarly activities.

BACKGROUND: Pediatric interventional radiology has grown as an advanced subspecialty with increased demand, number and complexity of cases, and number of pediatric institutions offering a pediatric interventional radiology service. Despite the overall increase in the number of pediatric interventionalists over the past two decades, there is a heterogeneity in their academic backgrounds and a lack of uniform training pathways. OBJECTIVE: To analyze the demographics, academic backgrounds and scholarly activities of pediatric interventionalists across the United States (U.S.) and Canada. MATERIALS AND METHODS: A list of all members of the Society for Pediatric Interventional Radiology was obtained and pediatric interventionalists at academic and private practice institutions in the U.S. and Canada were included. Publicly available online sources were used to gather demographic and educational information about each pediatric interventionalist, which included the online curriculum vitae, the HealthGrades.com and Doximity.com websites, and Elsevier's Scopus database. Demographic and educational data including age, gender, educational background, additional degrees, academic rank, previous leadership positions, and metrics of scholarly activities were recorded. Fellowships in diagnostic pediatric radiology, adult interventional radiology and/or pediatric interventional radiology were recorded. Mann-Whitney U tests and Kruskal-Wallis tests were used to compare differences between groups. RESULTS: One hundred and twenty-five pediatric interventionalists were included, of whom 24 (19.2%) were female. The mean age was 48.6 years (standard deviation [SD]: 10.6, median: 45 years, range: 36-82 years). There was no statistical difference between median age for male versus female pediatric interventionalists (44.5 years vs. 45 years, P=0.89). A majority of pediatric interventionalists were American medical school graduates (96, 76.8%), while 29 (23.2%) were international medical graduates. Eighty-three percent (104) of the pediatric interventionalists completed diagnostic radiology residency training in the U.S., most commonly at the University of Cincinnati in Ohio (6.4%) and Washington University in St. Louis, MO (5.6%). Among fellowship training, pediatric interventionalists completed a pediatric radiology fellowship (61.6%), adult interventional radiology fellowship (40%) and/or a dedicated pediatric interventional radiology fellowship (57.6%). The mean±SD (median) publications, citations and Hirsch index (h-index) for pediatric interventionalists were 32±45 (12), 68±1,317 (120) and 9±10 (5), respectively. There was a statistically higher number of publications, citations and h-index with increasing academic rank at the assistant, associate and professor levels (P<0.001 for all groups). International medical graduate pediatric interventionalists had a higher, but not statistically significant, median publication count (26 vs. 11, P=0.0.25), citation count (236 vs. 93, P=0.36) and h-index (9.0 vs. 5, P=0.24) compared to pediatric interventional radiologists from American medical schools. CONCLUSION: Pediatric interventionalists in North America are predominantly male, with about a quarter having graduated from international medical schools. Pediatric radiology fellowship, followed by pediatric interventional radiology fellowship, was the most frequently pursued training pathway.

Women with drug-resistant epilepsy: Surgery or pregnancy first?

OBJECTIVE: We compared women with drug-resistant focal epilepsy who had undergone surgery (WWE-S) with those who were managed medically (WWE-M) for maternal and fetal outcomes of their pregnancies. METHODS: We classified all WWE-S who were enrolled in a prospective registry of epilepsy and pregnancy (1998-2015) as those who underwent the surgery before pregnancy (WWE-SF) or after pregnancy (WWE-PF). The comparator group (WWE-M) was twice that number of age-matched women with focal epilepsy in this registry. Their clinical profile, anti-epileptic drug (AED) use, and pregnancy outcomes were extracted from the records of the registry. RESULTS: The number of completed pregnancies with known outcome was 74 for WWE-S (67 WWE-SF and 7 WWE-PF) and 134 for WWE-M. Seizures increased during pregnancy for fewer WWE-SF than for WWE-M (14.9% vs 39.6%, P = .001). Compared to WWE-M, fewer WWE-SF had dose escalation during pregnancy (28.4% vs 14.9%, P = .025). Preterm deliveries were more frequent in WWE-SF than WWE-M (24.6% vs 12.2%, P = .029). The differences between the WWE-SF and WWE-M regarding the rates of fetal loss (10.4% vs 6.7%, P = .255), major congenital malformations (8.5% vs. 11.1%, P = .395), and development quotient at 1 year of age <85 (42.5% vs 42.3%, P = .569) were not statistically significant. Compared to WWE-PF, fewer WWE-SF had AED dose escalation (14.9% vs 85.7%, P = .001) or increase in seizures (14.9% vs 100%, P = .001) during pregnancy. WWE-SF had fewer infants with development quotient <85 (41.0% vs 100%, P = .005). SIGNIFICANCE: WWE-SF can expect better control of seizures and decreased AED burden during pregnancy than WWE with focal epilepsies managed with medicines only. WWE who undergo surgery for epilepsy before their pregnancies can expect fewer seizures and lower AED burden during pregnancy.

Seizure outcome and its predictors after frontal lobe epilepsy surgery.

OBJECTIVES: Frontal lobe epilepsy (FLE) surgery is the second most common focal resective surgery for drug-resistant epilepsy. Not many studies are available regarding the long-term surgical outcome of FLE. We studied the longitudinal outcome and predictors of seizure outcome following FLE surgery in a sizeable cohort of patients. MATERIALS & METHODS: A total of 73 consecutive patients who underwent FLE surgery between January 1997 and May 2015 with a minimum follow-up of 1 year (range 1-16 years) were studied. Primary outcome was seizure freedom at last follow-up (Engel Class IA). "Seizure freedom" separately was defined as absence of seizures till last follow-up. Outcome predictors were subjected to multivariate analysis. Using Kaplan-Meier curve, we assessed the post-operative seizure freedom over time. RESULTS: Twenty-five patients (34%) were seizure-free till last follow-up. The seizure freedom was 45%, 34%, 26%, 20% and 14% at the end of 1st, 2nd, 3rd, 4th and 5th post-operative year, respectively. Engel class I outcomes were 48%, 41%, 56%, 57% and 53% at end of 1st, 2nd, 3rd, 4th and 5th post-operative year, respectively. Predictors of seizure recurrence on multivariate analysis were older age at surgery (P = 0.032), longer duration of epilepsy (P = 0.031), presence of interictal epileptiform discharges in post-operative EEG on 7th day (P = 0.005), 3 months (P = 0.005) and 1 year (P = 0.0179). In subgroup analysis, duration of epilepsy of less than 2 years before surgery was a significant predictor for achieving seizure freedom (P = 0.029). CONCLUSIONS: These results emphasize early surgery for better outcome in frontal lobe epilepsy. Post-operative EEG remained a good predictor for long-term outcome.

Ectopic pituitary adenomas: common presentations of a rare entity.

PURPOSE: Ectopic pituitary adenomas (EPA) are rare tumors thought to arise from embryological remnants along the route of normal pituitary migration. Clinically, these tumors vary in hormonal activity and can exert mass effect based on location and size. METHODS: We performed a single-center retrospective analysis of patients with diagnosis of ectopic pituitary adenoma from 2001 to 2018. RESULTS: Five patients were identified with EPA: a 48-year-old woman with suprasellar EPA treated with transsphenoidal removal of the tumor, a 44-year-old woman with cavernous EPA treated with transsphenoidal removal of the tumor, a 48-year-old woman with sphenoid EPA treated with cabergoline, a 45-year-old man with clival EPA treated with cabergoline and transsphenoidal surgical resection, and a 54-year-old man with clival EPA treated with cabergoline therapy. CONCLUSIONS: EPA should be considered as a differential diagnosis of juxta-sellar lesions. Appropriate hormonal testing may lead to early diagnosis, avoidance of unnecessary biopsy or surgery, and improved outcomes.

Glioblastoma in adults with neurofibromatosis type I: A report of two cases.

Neurofibromatosis type I (NF1) is a familial tumor syndrome with an autosomal-dominant inheritance. NF1-associated tumors often include neurofibromas, malignant peripheral nerve sheath tumors and pilocytic astrocytomas of the optic nerve. The presentation of NF1 patients with glioblastoma is a rare occurrence, with only a handful of cases reported in the literature. We report two cases of glioblastomas occurring in adults with NF1 and briefly review the relevant literature.

Pharmacotherapy for Patients with Atrial Fibrillation and Cerebral Microbleeds.

BACKGROUND: Patients with cerebral microbleeds have increased risk of intracranial hemorrhage and ischemic stroke. No trial specifically informs antithrombotic therapy for patients with cerebral microbleeds and atrial fibrillation. We investigated the safety of anticoagulation versus no anticoagulation with regard to cerebrovascular outcomes and mortality. METHODS: All consecutive atrial fibrillation patients from 2015 to 2018 with MRI evidence of ≥1 cerebral microbleed at time of imaging were reviewed. Patients were treated with warfarin, direct oral anticoagulants, or neither. Primary outcome was all-cause mortality informed by National Death Registry and the composite of ischemic and hemorrhagic stroke. All statistical tests were 2-sided and significant at P < .05. RESULTS: The median interval from patient identification until the end of electronic health record surveillance was 9.93 months (interquartile range, 2.83-19.17 months). We identified 308 atrial fibrillation patients with cerebral microbleeds; 128(41.6%) were on warfarin, 88(28.6%) on direct oral anticoagulants, and 92(29.9%) on neither. Over the surveillance interval, 87 deaths, 51 ischemic strokes, and 14 hemorrhagic strokes occurred. The estimated likelihoods of the composite stroke outcome and ischemic stroke only did not differ significantly among the 3 groups. However, patients taking direct oral anticoagulants had a significantly smaller likelihood of all-cause mortality than patients who were not anticoagulated (adjusted hazard ratio: .44[.23, .83], P=.012). CONCLUSIONS: In patients with coprevalent atrial fibrillation and cerebral microbleeds, we did not detect differences in subsequent ischemic stroke, hemorrhagic stroke, or both, comparing warfarin, direct oral anticoagulants, or neither. Patients treated with direct oral anticoagulants had better survival than nonanticoagulated patients.

"Time is Brain"-How early should surgery be done in drug-resistant TLE?

OBJECTIVES: To explore the effect of duration of epilepsy and delay in surgery on seizure outcome in patients operated for drug-resistant temporal lobe epilepsy (TLE). MATERIALS & METHODS: A total of 664 consecutive patients who underwent anterior temporal lobectomy (ATL) for TLE from 1995 to 2008 formed the study cohort. We divided them into two, one as seizure-free with or without antiepileptic drugs after ATL as "good outcome" (Engel class I a) and seizures of any type, any time after surgery as "poor outcome." The probability of seizure freedom/seizure recurrence based on the duration of epilepsy was compared using Kaplan-Meier curves, univariate Cox regression survival analysis, and multivariate Cox proportional hazards regression model. RESULTS: A total of 136 children and 528 adults underwent ATL during this period. Mean duration of epilepsy pre-ATL was 17.1 + 9.4 years. At mean follow-up of 8.5 years, 331 patients (49.8%) had good outcome and 333 (50.2%) had poor outcome. The hazard of seizure recurrence linearly increased with duration of epilepsy pre-ATL, from 1.5 (duration of epilepsy, 5-10 years) to 1.9 (duration of epilepsy, 10-15 years) to 2 (duration of epilepsy over 15 years). In addition, encephalitis as antecedent, bilateral mesial temporal sclerosis in MRI, normal histopathology, and spikes in postoperative EEG at 3 months and 1 year predicted poor seizure outcome. CONCLUSIONS: "Epilepsy duration" independently predicted both short- and long-term seizure outcome after surgery in TLE. "Lost years" translate into poor seizure outcome after ATL. Therefore, all cases of drug-resistant TLE should be referred to a surgical center at the earliest.

Is 'burned-out hippocampus' syndrome a distinct electro-clinical variant of MTLE-HS syndrome?

AIM: To study the clinical, electrophysiological and imaging characteristics of patients with unilateral mesial temporal lobe epilepsy (MTLE) with contralateral ictal onset on scalp EEG, viz. 'burned-out hippocampus' syndrome (MTLE-BHS). METHODS: MTLE-BHS was defined as TLE with unilateral hippocampal sclerosis (HS) without any dual pathology on MRI and contralateral ictal onset on scalp EEG, unlike in classical hippocampal sclerosis (HS). Consecutive "MTLE-BHS" patients evaluated at our Centre for Comprehensive Epilepsy Care from January 2005 to July 2014 were studied. Twenty-five cases of classic MTLE-HS operated during the same period were also analyzed for comparison. RESULTS: Seventeen patients were diagnosed to have MTLE-BHS. Mean age of seizure onset was 9.5±7.7years and the mean duration of epilepsy was18.2±7.3years. Epigastric aura was more common in MTLE-HS and fear, secondary generalized seizures and temporal polar changes on MRI were more prevalent in the MTLE-BHS subgroup. In the latter group, five (29%) exhibited seizure semiology and 2 (12%) had interictal discharges discordant to the side of MTS. Eight (47%) patients in the MTLE-BHS sub-group had normal medial temporal volume on Scheltens scale. Eight patients among MTLE-BHS underwent surgery (4 following intracranial monitoring that localized to the side of HS) with Engel class I outcome at 1year follow-up in 6 and Engel class II outcome in 2. CONCLUSION: Attenuation of ipsilateral fast ictal rhythms on scalp EEG as well as neocortical changes are likely to be deterministic factors for MTLE-BHS as opposed to the severity of hippocampal atrophy. Considering good post-operative outcomes, intracranial monitoring for surgical selection is not mandatory in MTLE-BHS despite discordant semiology and ictal onset, in the presence of inter-ictal, functional imaging and neuropsychology data concordant to the side of HS.

Subclinical respiratory dysfunction in chronic cervical cord compression: a pulmonary function test correlation.

OBJECTIVE Respiratory abnormalities are well documented in acute spinal cord injury; however, the literature available for respiratory dysfunction in chronic compressive myelopathy (CCM) is limited. Respiratory dysfunction in CCM is often subtle and subclinical. The authors studied the pattern of respiratory dysfunction in patients with chronic cord compression by using spirometry, and the clinical and surgical implications of this dysfunction. In this study they also attempted to address the postoperative respiratory function in these patients. METHODS A prospective study was done in 30 patients in whom cervical CCM due to either cervical spondylosis or ossification of the posterior longitudinal ligament (OPLL) was diagnosed. Thirty age-matched healthy volunteers were recruited as controls. None of the patients included in the study had any symptoms or signs of respiratory dysfunction. After clinical and radiological diagnosis, all patients underwent pulmonary function tests (PFTs) performed using a standardized Spirometry Kit Micro before and after surgery. The data were analyzed using Statistical Software SPSS version 13.0. Comparison between the 2 groups was done using the Student t-test. The Pearson correlation coefficient was used for PFT results and Nurick classification scores. A p value < 0.05 was considered significant. RESULTS Cervical spondylotic myelopathy (prolapsed intervertebral disc) was the predominant cause of compression (n = 21, 70%) followed by OPLL (n = 9, 30%). The average patient age was 45.06 years. Degenerative cervical spine disease has a relatively younger onset in the Indian population. The majority of the patients (n = 28, 93.3%) had compression at or above the C-5 level. Ten patients (33.3%) underwent an anterior approach and discectomy, 11 patients (36.7%) underwent decompressive laminectomy, and the remaining 9 underwent either corpectomy with fusion or laminoplasty. The mean preoperative forced vital capacity (FVC) (65%) of the patients was significantly lower than that of the controls (88%) (p < 0.001). The mean postoperative FVC (73.7%) in the patients showed significant improvement compared with the preoperative values (p = 0.003). The mean postoperative FVC was still significantly lower than the control value (p = 0.002). The mean preoperative forced expiratory volume in 1 second (FEV1) (72%) of the patients was significantly lower than that of the controls (96%) (p < 0.001). The mean postoperative FEV1 (75.3%) in the cases showed no significant improvement compared with the preoperative values (p = 0.212). The mean postoperative FEV1 was still significantly lower than the control value (p < 0.001). The mean postoperative FEV1/FVC was not significantly different from the control value (p = 0.204). The mean postoperative peak expiratory flow rate was significantly lower than the control value (p = 0.01). The mean postoperative maximal voluntary ventilation was still significantly lower than the control value (p < 0.001). On correlating the FVC and Nurick scores using the Pearson correlation coefficient, a negative correlation was found. CONCLUSIONS There is subclinical respiratory dysfunction and significant impairment of various lung capacities in patients with CCM. The FVC showed significant improvement postoperatively. Respiratory function needs to be evaluated and monitored to avoid potential respiratory complications.

Does F-18 FDG-PET substantially alter the surgical decision-making in drug-resistant partial epilepsy?

OBJECTIVE: There is a dearth of information on the critical utility of positron emission tomography (PET) in choosing candidates for epilepsy surgery especially in resource-poor countries where it is not freely available. This study aimed to critically analyze the utility of FDG-PET in the presurgical evaluation and surgical selection of patients with DRE based on the results obtained through its use in our comprehensive epilepsy program. METHODS: From 2008 to 2012, 117 patients with drug-resistant epilepsy underwent F-18 fluoro-deoxy-glucose (FDG) PET in our center. We utilized their data to audit the utility of PET in choosing/deferring patients for surgery. RESULTS: Of the 117 patients (age: 5-42years) who underwent F-18 FDG-PET, 64 had normal MRI, and 53 had lesions. Electroclinical data favored temporal ictal onset in 48 (41%), extratemporal in 60 (51.3%), and uncertain lobar localization in 9 (7.7%). The topography of PET hypometabolism was localizing in 53 (45.3%), lateralizing in 12 (10.3%), and 52 (44.4%) had either normal or discordant results. In the nonlesional group, focal hypometabolism was concordant to the area of ictal onset in 27 (41.5%) versus 38 (58.5%) in the lesional group (p=0.002). Greater concordance was noted in temporal lobe epilepsy (TLE) (78.0%) as compared to extratemporal epilepsy (ETPE) (28.6%) (p<0.001). Positron emission tomography was more concordant in patients with mesial temporal sclerosis than in those with other lesions (82.8% versus 50%) (p=0.033). Positron emission tomography helped in surgical decision-making in 68.8% of TLE and 23.3% of ETPE cases. Overall, 37 patients (31.6%) were directly selected for resective surgery based on PET results. CONCLUSIONS: Positron emission tomography, when utilized judiciously, remained an ancillary tool in the surgical selection of one-third of patients with drug-resistant partial epilepsy, although its utility as an independent tool is not very promising.

Lack of IDH1 mutation in astroblastomas suggests putative origin from ependymoglial cells?

Astroblastomas are extremely rare neuroepithelial tumors of uncertain histogenesis, affecting children and young adults, and constitute a new addition to the WHO 2000 classification of CNS tumors. We report the largest series of nine cases diagnosed in a single institute over the last 13 years and review published literature. Mean age at presentation was 12.8 years (range: 22 months to 27years). Seven out of nine cases were supratentorial (frontal/frontoparietal - three, parieto-occipital - three, parafalcine - one), one was intraventricular and another was optochaismatic/suprasellar. Five cases were high grade (anaplastic) astroblastomas with Ki-67 labeling index of 8-10%. Immunohistochemical and ultrastructural evidence suggesting origin from cells intermediate between ependymocytes and astrocytes is presented. The histogenetic origin of these tumors remains speculative. But the lack of Isocitrate dehydrogenase 1 (IDH1) mutation as detected by immunohistochemistry in this study, which is similar to ependymomas supports putative origin from ependymoglial cells. Out of the nine cases, recurrence was noted in one case, 12 months after gross total resection with progression to high grade in the recurrent tumor. There is no recommended treatment protocol due to the rarity of this entity and prognostic factors are yet to be established.