Anatomical localization of the cavernous sinus dural fistula by 3D rotational angiography with emphasis on clinical and therapeutic implications.

BACKGROUND AND PURPOSE: Carotid cavernous sinus dural arteriovenous fistulas (CSDAVFs) are presumed to be located within the walls of the cavernous sinus, however the exact fistulous site has not yet been studied by angiographic or anatomical methods. The present study aimed to localize CSDAVFs with the help of 3D rotational angiography (RA) and correlated the observations with clinical and angiographic findings. MATERIALS AND METHODS: The CSDAVFs were categorized as dural, extradural or osseous based on the site of convergence of feeders into the venous sac. Extradural CSDAVFs were further subcategorized into posteromedial, posterolateral and anterior subtypes, depending on proximity to a possible venous plexus. This classification was correlated with various clinical presentations and angiographic subtypes. RESULTS: Thirty-seven patients were included in the final analysis. The sac was identified in all the patients and the mean sac size of the fistula was small (<4mm). Dural type was associated with exclusive cortical venous drainage. Extradural anterior CSDAVF showed tendency towards younger age predilection. Extradural posterolateral CSDAVF was more often associated with initial oculomotor nerve palsy and this observation was statistically significant. Discordancy between the location of the fistula and the side of clinical affection was observed in midline fistulas such as osseous CSDAVF and posteromedial type of extradural CSDAVF. CONCLUSIONS: CSDAVF is a heterogeneous vascular disorder involving the sphenoclival bone, extradural space and dura, homologous to the epidural-dural shunts of vertebra with a common clinical presentation of orbital manifestations. Preoperative localization of the fistula could explain enigmatic observations and potentially simplify its interventional management.

The decade after subthalamic stimulation in advanced Parkinson's disease: A balancing act.

AIM: The duration of improvement in quality of life after subthalamic nucleus deep brain stimulation (STN DBS) for Parkinson's disease (PD) and the presurgical identification of factors predicting sustained clinical benefits have implications in patient selection and timing of surgery. These aspects were assessed in patients who underwent yearly assessment for at least 7 years after surgery. MATERIALS AND METHODS: The quality of life, motor and cognitive outcomes of 25 patients who completed the 7-year assessment, and 12 patients who completed the 10-year assessment, were analyzed. RESULTS: The improvement in quality of life was sustained only for 5 years, while the severity of motor signs and motor fluctuations remained reduced at 7 and 10 years. Tremor and rigidity showed more enduring reduction than bradykinesia and axial signs. The dose reduction in medications could be maintained until 7 years, by which time, the axial scores were worse than that seen at the pre-DBS levels. At 10 years, a higher levodopa requirement and recurrence of dyskinesias were noted. Patients with greater pre-DBS levodopa-responsive motor signs had greater long-term motor improvement. CONCLUSIONS: STN DBS performed in patients with advanced motor fluctuations and severe dyskinesias provide only an average of 5 years of quality of life improvement. STN DBS in patients with motor signs that are less responsive to levodopa results in shorter duration of clinical benefits. The improvements in the severity of motor fluctuations, rigidity, and tremor are the most enduring benefits of STN DBS that last a decade . However, these are offset by worsening axial and cognitive functions, bradykinesia, a higher levodopa requirement, and recurrence of dyskinesias by the end of the decade.

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.

Validity of Montreal Cognitive Assessment in non-english speaking patients with Parkinson's disease.

BACKGROUND: The Montreal Cognitive Assessment is a brief and easy screening tool for accurately testing cognitive dysfunction in Parkinson's disease. We tested its validity for use in non-English (Malayalam) speaking patients with Parkinson's disease. MATERIALS AND METHODS: We developed a Malayalam (a south-Indian language) version of Montreal Cognitive Assessment and applied to 70 patients with Parkinson's disease and 60 age- and education-matched healthy controls. Metric properties were assessed, and the scores were compared with the performance in validated Malayalam versions of Mini Mental Status Examination and Addenbrooke's Cognitive Examination. RESULTS: The Montreal Cognitive Assessment-Malayalam showed good internal consistency and test-retest reliability and its scores correlated with Mini Mental Status Examination (patients: R = 0.70; P < 0.001; healthy controls: R = 0.26; P = 0.04) and Addenbrooke's Cognitive Examination (patients: R = 0.8; P < 0.001; healthy controls: R = 0.52; P < 0.001) scores. CONCLUSION: This study establishes the reliability of cross-cultural adaptation of Montreal Cognitive Assessment for assessing cognition in Malayalam-speaking Parkinson's disease patients for early screening and potential future interventions for cognitive dysfunction.

Malformation in index pregnancy in women with epilepsy is not followed by recurrence in subsequent pregnancy.

Use of antiepileptic drugs (AEDs) in pregnant women with epilepsy (WWE) is associated with an increased risk of major congenital malformations (MCM). Previous studies have suggested that WWE who had a malformation in their index pregnancy were at an increased risk of recurrence in future pregnancies. We aimed to assess the risk of recurrence of MCM in 1,616 WWE from Kerala Registry of Epilepsy and Pregnancy. The pregnancy outcome of women (n = 246) with two prospective pregnancies in the registry were analyzed. They had partial seizures with or without generalization (57.3%) or generalized seizures (42.7%). Polytherapy was used in 26.4% (index pregnancy) and 23.6% (follow-up pregnancy). The mean dosage of AED for valproate was 498 mg/day and carbamazepine was 555 mg/day. The malformation rate in the index pregnancy was 8.5% (21/246) and in the follow-up pregnancy was 8.9% (22/246) with only one recurrence. There was no increased risk of MCM in follow-up pregnancy for those who had MCM in the index pregnancy (p = 0.70; OR 0.49; 95% CI 0.06-3.80). The use of any specific drug, continuation of the same drug or a change in drug therapy between two pregnancies did not alter the recurrence risk.

Screening performance of diabetes risk scores among Asians and whites in rural Kerala, India.

We compared the screening performance of risk scores for Asians and whites for diabetes, dysglycemia, and metabolic syndrome. Our subjects were 451 people aged 15 to 64 years who participated in a cohort study from May 2003 through September 2010 in a rural area of the Thiruvananthapuram district of Kerala, India. All outcome measures showed overlap in the range of area under the receiver operating characteristic curves of Asian and white diabetes risk scores (DRSs). Asian and white DRSs performed similarly in rural India.

Deep Brain Stimulation for Parkinson's Disease-the Developing World's Perspective.

Background: Deep brain stimulation (DBS) is the most widely used device-assisted therapy in patients with moderately advanced stages of Parkinson's disease (PD) experiencing motor complications. Only a minority of eligible patients get the opportunity to undergo DBS in the developing world. Objectives: To examine the proportion and characteristics of patients with motor complications of PD who are willing for DBS and who undergo surgery. Methods: Patients with motor complications of PD eligible for DBS over a five-year study period (2016-2020) were included. The demographic, clinical and socio-economic characteristics and information on their status in 2021 were collected and analyzed. Results: Among 1017 patients, 223 had motor symptoms qualifying for DBS and follow-up information available. Only 78 (35%) opted for surgery. The willing patients had higher socioeconomic status, were older and had longer duration of PD and motor complications, more freezing of gait, cognitive symptoms, and neuropsychiatric disturbances. 37 of them were found unfit during pre-operative work-up; only 41 (18%) with motor complications were finally taken up for DBS. Age, duration or severity of motor symptoms did not differ between patients who were finally selected for surgery and those who were not. Conclusions: Less than one-fifth of our patients with motor complications of PD finally underwent DBS. The patients appeared to wait till the late stages of PD, before making a decision on availing surgical treatment. The delay resulted in nearly half of them being found unfit in pre-operative work-up. Our findings may enable clinicians to counsel eligible patients more efficiently.

Pattern and Severity of Leukoaraiosis and Microvascular Resistance- Inputs from a TCD Study from South Asia.

Background and Purpose: Leukoaraiosis is thought to be related to long-standing microvascular ischemia. The pathogenic mechanisms and hemodynamic changes could be different for periventricular and deep white matter leukoaraiosis. In this cross-sectional study, we examined whether the Pulsatility Index (PI) in Transcranial Doppler ultrasonography (TCD), which can give indirect information regarding downstream microvascular resistance and compliance, is different for leukoaraiosis in periventricular and deep locations. Correlation between presence of leukoaraiosis and PI was also studied since it was not studied in South-Asian patients before. Methods: Consecutive patients with suspected lacunar stroke or white-matter disease, undergoing MR brain imaging were included. Vascular imaging was done with CT or MR Angiography to rule out significant (>50%) stenosis. Fazeka's grading was done for severity of leukoaraiosis and mean PI in the middle cerebral artery (MCA) was obtained with trans-temporal TCD. Results: Ninety patients (Mean age 61 ± 10.9 years, 29% females) were available for final analysis. Age, hypertension, diabetes mellitus, CAD, and presence of leukoaraiosis were strongly associated with elevated mean PI in univariate analysis. In multivariate analysis, presence of leukoaraiosis was significantly associated with higher mean PI after adjusting for other variables. Mean PI strongly correlated with both periventricular (Spearman's correlation coefficient 0.56, P = 0.01) and deep white matter (Spearman's correlation coefficient 0.63, P = 0.01) leukoaraiosis. Conclusions: Our study confirms the correlation of Pulsatility Index with leukoaraiosis in South-Asian patients. Interestingly, changes in microvascular resistance appeared to be similar for both periventricular and deep white matter leukoaraiosis in spite of potential differences in etiopathogenesis.

Cognitive outcome following bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease-a comparative observational study in Indian patients.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor symptoms and motor complications of Parkinson's disease (PD). The intervention is expected to result in some cognitive changes, the nature of which is not uniform across the studies which have reported them. PD itself is associated with progressive cognitive decline and hence longitudinal follow-up studies with medically managed control group of patients are needed to explore the cognitive deficits attributable to DBS. METHODS: We conducted a prospective comparative observational study to assess the effects of bilateral STN DBS on cognition. Cognitive functions were assessed at baseline and after a minimum of two years after surgery, and compared with baseline and follow-up assessments in patients on medical management alone. RESULTS: Thirty-four patients with PD who underwent bilateral STN DBS and thirty-four medically managed patients participated in the study. At a mean follow-up of around 33 months, we found a significant decline in verbal fluency scores in the DBS group compared to those on medical management alone (1.15 ± 1.23 vs 0.59 ± 0.93, p = 0.034) and a trend for decline was noted in digit span test. There was no difference in the performance in tests addressing other cognitive domains, or tests of global cognitive function. No patient developed dementia. Motor functions and activities of daily living (ADL) were significantly better in the surgical group. CONCLUSION: STN DBS results in minor deficits in executive functions, particularly verbal fluency. These may be inconsequential, considering the marked improvement in motor functions and ADL.

Treatment in a Stroke Unit and Risk Factor Control Reduce Recurrent Stroke Risk.

INTRODUCTION: Risk factor control is an important predictor of risk of stroke recurrence. The attributable fraction which estimates the excess risk among the exposed stroke survivors has not been studied previously. We studied the attributable fraction for stroke recurrence in consecutive incident cases of recurrent stroke. METHODS: A case-control study with incident cases of recurrent stroke and controls matched for age and poststroke period was done. A structured interview was done to collect data on sociodemographic variables, lifestyle, and medication adherence. The risk factors, treatment of index stroke, and outcome were collected. Logistic regression analysis was done to find out the factors associated with stroke recurrence. Attributable fraction and average attributable fraction were calculated. RESULTS: Among the 103 matched pairs, more than 70% were rural residents. Male gender (OR 2.59; 95% CI 1.05-6.42), the presence of depression (OR 8.67; 95% CI 2.80-26.84), memory problem (OR 10.12; 95% CI 2.48-41.34), uncontrolled diabetes (OR 3.19; 95% CI 1.42-7.19), cardioembolic stroke (OR 4.45; 95% CI 1.12-17.62), and index stroke not being treated in a stroke unit (OR 6.60; 95% CI 2.86-15.23) were associated with increased risk of stroke recurrence. The maximum average attributable fraction for stroke recurrence risk was attributed to index stroke not being treated in the stroke unit and uncontrolled diabetes. CONCLUSION: The index stroke treated in a comprehensive stroke care unit and control of risk factors can reduce recurrent stroke risk among stroke survivors. This population-attributable risk is important in planning secondary stroke prevention strategies.

Clinical and functional outcome and factors predicting prognosis in osmotic demyelination syndrome (central pontine and/or extrapontine myelinolysis) in 25 patients.

AIMS: To assess the functional and clinical outcome in a sizeable cohort of patients with osmotic demyelination syndrome (ODS) and to characterise the factors which could predict the final outcome. METHODS: Twenty five consecutive patients with ODS formed the study cohort. The diagnosis of ODS was based on clinical features with corroborating imaging findings. Two functional scales--Functional Independent Measure (FIM) and Disability Rating Scale (DRS)--were applied to assess the functional status at the time of admission, discharge and last follow-up. Patients who became independent for activities of daily living (ADL) at last follow-up were classified as favourable outcome, and those who died or became dependent for ADL were classified as a poor outcome group respectively. The Fisher exact test and Mann-Whitney U test were used to assess categorical and continuous variables respectively. RESULTS: The mean age at diagnosis was 53 ± 14 years. Five (20%) had central pontine myelinolysis, seven (28%) had extrapontine myelinolysis, and 13 (52%) had both. Hyponatraemia and hypokalaemia were noted in 20 (80%) and 10 (40%) patients respectively. Six (24%) received intravenous methylprednisolone. Eleven (46%) had a favourable outcome at a mean follow-up of 2.2 ± 2.5 years. Hyponatraemia ≤ 115 mEq (p=0.04), associated hypokalaemia (p=0.04) and low Glasgow Coma Scale (GCS) (p=0.008) at presentation were predictive of poor outcome. The mean FIM score at admission (p=0.05) and at discharge (p=0.01), and mean DRS at admission (p=0.05) were predictive of poor outcome. CONCLUSIONS: Higher GCS scores, better scores in functional scales in hospital, less severe hyponatraemia and absence of superadded hypokalaemia predicted favourable outcome.

Women and Stroke: Different, yet Similar.

BACKGROUND: The impact of gender on acute ischemic stroke, in terms of presentation, severity, etiology, and outcome, is increasingly getting recognized. Here, we analyzed the gender-related differences in etiology and outcome of ischemic stroke in South India. METHODS: Patients with first ever ischemic stroke within 1 week of onset presenting to the Comprehensive Stroke Care Centre, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India, were included in our study. Clinical and risk factor profile was documented. The stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) at onset, and stroke subtype classification was done using Trial of Org 10172 in Acute Ischemic Stroke criteria. The 3-month functional outcome was assessed using the modified Rankin Scale (mRS) with excellent outcome defined as an mRS ≤2. RESULTS: Of the 742 patients, 250 (33.7%) were females. The age, clinical profile, and rate of reperfusion therapies did not differ between the genders. Women suffered more severe strokes (mean NIHSS 9.5 vs. 8.4, p = 0.03). While large artery atherosclerosis was more common in men (21.3% vs. 14.8%, p = 0.03), cardioembolic strokes secondary to rheumatic heart disease were more common in women (27.2% vs. 19.7%, p = 0.02). Men had a better 3-month functional outcome compared to women (68.6% vs. 61.2%, p = 0.04), but was not statistically significant after adjusting for confounders. CONCLUSION: Our data, from a single comprehensive stroke unit from South India, suggest that stroke in women are different, yet similar in many ways to men. Guideline-based treatment can result in comparable short-term outcomes, irrespective of admission stroke severity.

"Sequential multimodality stimulation" for post-stroke-hemineglect: Feasibility and outcome in a pilot randomized controlled trial.

OBJECTIVE: To test the feasibility and efficacy of multimodality stimulation combined with motor tasking as a corrective strategy for hemineglect following right hemispheric ischemic strokes. MATERIAL AND METHODS: A prospective randomized controlled single blinded clinical trial was conducted over eighteen months from January 2017. All patients with right hemispheric ischemic strokes were screened for hemineglect and those fulfilling criteria were recruited and randomized. Patients under the therapy group (TG) received the intervention based on a structured protocol in addition to standard physiotherapy. The control group (CG) received standard physiotherapy alone. NIHSS, mRS and Neuropsychological test scores were recorded at different time points. The primary outcome measures (neuropsychological test scores) were compared between the two groups (Student's t-test to find out the difference in outcome measures) at one and three months post-stroke. RESULTS: Of the 14 patients recruited, data from 12 were available for analysis, 5 patients in TG and 7 in CG. There was a trend for better hemineglect and functional outcomes in TG. CONCLUSION: Multimodality stimulation, in addition to standard physiotherapy, is feasible and potentially results in better neurocognitive and functional recovery following right hemispheric ischemic strokes. However, larger studies are warranted to prove these preliminary observations beyond doubt.

Cerebral Amyloid Angiopathy: A Clinico-Radiological Study from South India.

INTRODUCTION: Cerebral amyloid angiopathy (CAA) is a major cause of intracerebral hemorrhage (ICH) and cognitive decline in the elderly. Since it is rarely reported from the developing world, we looked into the clinical profile and neuroimaging associations of CAA. MATERIALS AND METHODS: Ours was a retrospective case series of subjects diagnosed with probable/possible CAA between January 2006 and December 2015 as per Boston criteria. Clinical profile and neuroimaging were reviewed for markers of CAA. Details of any recurrent clinical events and functional status were collected from follow-up records. RESULTS: We had 28 subjects in the series with men outnumbering women, and the mean age was 70.17 ± 8.85 years (55-87 years). At the initial presentation, ICH was most frequent-10/28 (35.7%) patients, followed by transient neurological events (TNE = 25%) and cognitive disturbances (21.4%). Less than half of the patients received a diagnosis of CAA at the initial presentation itself. In total, 68% of our patients had cognitive dysfunction at admission. In our series, 12 had seizures and 9 had a history of TNE. The majority of our patients had vascular risk factors also. Leukoaraiosis showed an association with cognitive dysfunction (P = 0.044). Superficial siderosis and subarachnoid hemorrhage (SAH) showed a positive association with seizures and TNE, respectively. However, ICH showed no association with risk factors or imaging markers of CAA. CONCLUSIONS: CAA patients, with a high prevalence of vascular risk factors mostly presented with ICH. The presence of SAH and superficial siderosis on MRI was associated with presentation as TNE and seizures, respectively.

Early versus late antiepileptic drug withdrawal following temporal lobectomy.

PURPOSE: To compare the seizure outcome following early and late complete antiepileptic drug (AED) withdrawal following anterior temporal lobectomy (ATL) for mesial temporal lobe epilepsy (MTLE). METHOD: All the patients who were seizure free for one year following ATL were offered early or late AED withdrawal. AEDs were discontinued starting at one year in those who opted for early withdrawal. Patients who opted for late withdrawal were continued on single AED for three years following surgery before attempting complete discontinuation. RESULTS: Of the 135 study patients, 65 opted for early AED withdrawal and 70 for late withdrawal. The mean postoperative follow-up duration was 10.4 ± 1.3 (Range, 8-12) years. At three years following surgery, seizure recurrence occurred in 23 (35.4 %) patients in the early withdrawal group and in 10 (14.3 %) patients in late withdrawal group (p = 0.005; relative risk [RR], 2.48; 95 % confidence interval [CI], 1.28-4.80). At last follow-up, 27 (41.5 %) patients in the early withdrawal group and 26 (37.1 %) in late withdrawal group had recurrence (p = 0.60; RR, 1.12, 95 % CI, 0.74-1.70). At last followup, 80 (59.3 %) patients were off AEDs. During the terminal one year, 123 (91 %) patients were seizure free, similar in the two groups. CONCLUSIONS: This nonrandomized controlled study suggests that early complete AED withdrawal starting one year following ATL is associated with a higher risk of early seizure recurrence. However, long term seizure outcome is similar in early and late AED withdrawal groups.

Dopamine Receptor D3 rs6280 is Associated with Aberrant Decision-Making in Parkinson's Disease.

BACKGROUND: The functional Ser9Gly single nucleotide polymorphism (SNP) in the dopamine D3 receptor gene is associated with impulse control disorders (ICD) in Parkinson's disease (PD) in Indian patients. Whether the same SNP modulates impulsivity in PD patients without active ICD is unknown. We aimed to compare decision-making under uncertainty in PD patients with DRD3 p.S9G (rs6280) variants CT/CC or TT. METHODS: We conducted a cross-sectional study including PD patients (n = 78) whose DRD3 p.S9G (rs6280) genotypic status was known (CC, CT, and TT). Decision-making was assessed using the Iowa Gambling Task (IGT). RESULTS: IGT total (p = 0.267) or block scores did not differ between the DRD3 rs6280 variant groups. Deck choice analysis revealed that the CT/CC group showed a skewed preference in deck choice (p = 0.002) due to significantly fewer draws from deck B, compared to all other decks (deck A, p < 0.001; deck C, p = 0.004; deck D, p = 0.002). CONCLUSIONS: The functional Ser9Gly DRD3 variant is associated with aberrant decision-making under uncertainty in PD patients without active ICD. This ability to modulate impulsivity may underlie its association with clinical ICD in PD.

Optimal timing and differential significance of postoperative awake and sleep EEG to predict seizure outcome after temporal lobectomy.

OBJECTIVE: To evaluate the prognostic value of postoperative EEGs to estimate post anterior temporal lobectomy (ATL) seizure outcome. METHODS: We studied postoperative EEGs in 325 consecutive patients who had minimum five years of post-ATL followup. Interictal epileptiform discharges (IEDs) present only during sleep were classified as sleep IEDs. We defined favorable final-year outcome as no seizures during the final one year and favorable absolute-postoperative outcome as no seizures during the entire postoperative period. RESULTS: At mean follow-up of 7.3 ±â€¯1.8 years, 281 (86.5%) patients had favorable final-year outcome while 161 (49.5%) had favorable absolute-postoperative outcome. IEDs on three months and one year EEG were associated with unfavorable outcomes while IEDs at 7th day had no association with outcomes. Sleep record increased the yield of IEDs by 30% at each time-point without compromising predictive value. EEG at one year predicted the risk of seizure recurrence on drug withdrawal. CONCLUSION: While EEG at three months and at one-year after ATL predicted seizure outcome, EEG at 7th day was not helpful. Sleep record increases the sensitivity of postoperative EEG without compromising specificity. SIGNIFICANCE: Both awake and sleep EEG provide useful information in postoperative period following ATL.

Predictors of seizure outcome following resective surgery for drug-resistant epilepsy associated with focal gliosis.

OBJECTIVEThe authors studied the clinical characteristics and postoperative outcomes of drug-resistant epilepsy associated with focal gliosis.METHODSFrom their epilepsy surgery database, the authors selected the patients with drug-resistant epilepsy and MRI-defined focal gliosis who underwent focal resective surgery. All patients underwent standard presurgical evaluation. Intracranial electroencephalography (EEG) was performed in patients with discordant presurgical data, ill-defined lesions, and lesions close to eloquent regions. Completeness of resection was defined on the basis of extraoperative and intraoperative electrocorticography studies. Favorable postoperative outcome was defined as Engel class I outcome during the last 2 years of follow-up.RESULTSSixty-six patients fulfilled inclusion criteria. An initial precipitating injury was present in 38 (57.6%) patients, mainly in the form of perinatal injury (n = 10), trauma (n = 10), and meningoencephalitis (n = 8). Gliosis involved a single lobe in 38 (57.6%) patients and 2 adjacent lobes in 14 (21.2%) patients; the remaining 14 (21.2%) patients had multilobar gliosis. In patients with unilobar or bilobar gliosis, the posterior region of the head was involved in 34 (65%) patients and the frontal lobes in 12 (23%) patients. During a median follow-up of 4 years (range 2-9 years), 41 (62.1%) patients had favorable outcome. On multivariate analysis, the presence of a well-defined aura (p = 0.019), electrocorticographically defined completeness of resection (p = 0.024), and normal postoperative EEG findings at 1 year (p = 0.003) were predictive of favorable postoperative seizure outcome.CONCLUSIONSFocal gliosis is a common etiology for drug-resistant extratemporal epilepsy in developing countries and is most often located in the posterior region of the head. The majority of these patients have perinatal injuries or neurological infections as initial precipitating injuries. Patients with focal gliosis have good postoperative seizure outcomes after well-planned resective surgery.

Outcome after seizure recurrence on antiepileptic drug withdrawal following temporal lobectomy.

OBJECTIVE: To study the long-term outcome following seizure recurrence on antiepileptic drug (AED) withdrawal after anterior temporal lobectomy for mesial temporal lobe epilepsy. METHODS: We retrospectively studied the AED profile of patients who had a minimum of 5 years of postoperative follow-up after anterior temporal lobectomy for mesial temporal lobe epilepsy. Only those patients with hippocampal sclerosis or normal MRI were included. AED withdrawal was initiated at 3 months in patients on ≥2 drugs and at 1 year for patients on a single drug. RESULTS: Three hundred eighty-four patients with median postoperative follow-up of 12 years (range, 7-17 years) were included. Of them, 316 patients (82.3%) were seizure-free during the terminal 1 year. AED withdrawal was attempted in 326 patients (84.9%). At last follow-up, AEDs were discontinued in 207 patients (53.9%). Seizure recurrence occurred in 92 patients (28.2%) on attempted withdrawal. After a median postrecurrence follow-up of 7 years, 79 (86%) of them were seizure-free during the terminal 2 years. AEDs could be stopped in 17 patients (18.5%) and doses were reduced in another 57 patients (62%). Patients with febrile seizures, normal postoperative EEG at 1 year, and duration of epilepsy of <20 years (FND20 score) had 17% risk of seizure recurrence on attempted AED withdrawal. We also formulated a score to predict the chances of AED freedom for the whole cohort. CONCLUSION: Patients with seizure recurrence on AED withdrawal have good outcome with 86% becoming seizure-free and 18% becoming drug-free after initial recurrence. A FND20 score helps in predicting recurrence on AED withdrawal.

Interictal regional paroxysmal fast activity on scalp EEG is common in patients with underlying gliosis.

OBJECTIVE: Interictal regional paroxysmal fast activity (RPFA) on scalp EEG is common in patients with focal cortical dysplasia (FCD). Little data exists regarding the presence of RPFA in other etiologies. METHODS: We studied the association between RPFA and etiology on MRI in patients with drug resistant focal epilepsy undergoing presurgical evaluation in 2011. RPFA was defined as ≥3 consecutive spikes with a frequency of ≥10 Hz lasting ≥300 ms but <4 s. RESULTS: 626 patients fulfilled the inclusion criteria. Of these, 138 (22%) patients had RPFA while rest had other interictal epileptiform discharges (IEDs). RPFA was located at posterior head region in 52.2% patients, frontal regions in 24.6% patients and over temporal regions in 17.4% patients. Focal gliosis (61, 44%) and FCD (27, 19%) were common etiologies in patients with RPFA. Compared to patients with other IEDs, patients with RPFA were more likely to have focal gliosis (61/138 vs. 39/488; p < 0.0001) or FCD (27/138 vs 37/488; p < 0.001) as the etiology of epilepsy. CONCLUSION: In developing countries, focal gliosis is more common than FCD as the underlying etiology in patients with RPFA on scalp EEG. SIGNIFICANCE: Focal gliosis should be considered as one of the common substrate for RPFA on scalp EEG.