A controversial question: Can morphometry and clinical history be enough to diagnose hippocampal dysplasia?

The presence of dysmorphic neurons with strong cytoplasmatic accumulation of heavy non-phosphorylated neurofilament is crucial for the diagnostics of focal cortical dysplasia type II (FCDII). While ILAE's classification describes neocortical dysplasias, some groups have reported patients with mesial t abnormal neurons in the hippocampus of mesial temporal lobe epilepsy. Here we report a patient with such abnormal neurons in the hippocampus and compared it with previous reports of hippocampal dysplasia. Finally, we discuss the need for diagnostic criteria of hippocampal dysplasia.

Dyke-Davidoff-Masson Syndrome: Main clinical and radiological findings- systematic literature review.

INTRODUCTION: Dyke-Davidoff-Masson syndrome (DDMS), or cerebral hemiatrophy, was first described in 1933. It is characterised by cerebral injury that causes hypoplasia in one of the cerebral hemispheres. The disease has different clinical degrees and two aetiologies: congenital and acquired. Radiological findings depend on the degree of injury and the patient's age at the time. OBJECTIVE: To provide information on the main clinical and radiological characteristics of this disease. METHODS: A systematic review of the PubMed, MEDLINE, and LILACS databases was conducted using only one keyword. Dyke-Davidoff-Masson syndrome. A total of 223 studies were identified, and the results are presented in tables and graphics. RESULTS: The mean age of the patients was 19.44 (0-83 years), and the majority were male (55.32%). The most common types of epileptic seizures were generalised tonic-clonic seizures (31 cases), focal impaired awareness seizures (20 cases), focal motor seizures (13 cases), focal to bilateral tonic-clonic seizures (nine cases), and focal myoclonic seizures (one case). The main features of the disease were rapid deep tendon reflexes and extensor cutaneous-plantar tendon reflexes (30 cases - 16%), contralateral hemiparesis or hemiplegia (132 cases - 70%), gait alterations (16 cases - 9%), facial paralysis (nine cases - 5%), facial asymmetry (58 cases - 31%), limb asymmetry (20 cases - 11%), delayed developmental milestones (39 cases - 21%), intellectual disability (87 cases - 46%), and language/speech disorders (29 cases - 15%). Left hemisphere atrophy was the most prevalent. CONCLUSION: DDMS is a rare syndrome, and several questions regarding this disease remain unanswered. This systematic review aims to elucidate the most common clinical and radiological aspects of the disease and emphasises the need for further investigation.

Time course of hemispheric cerebral volume after decompressive craniectomy in malignant middle cerebral artery stroke.

BACKGROUND: Brain edema is the leading cause of death in patients with malignant middle cerebral artery (MCA) infarction. Midline shift (MLS) has been used as a monohemispheric brain edema marker in several studies; however, it does not precisely measure brain edema. It is now possible to directly measure hemisphere brain volume. Knowledge about the time course of brain edema after malignant middle cerebral artery infarction may contribute to the condition's management. OBJECTIVE: Therefore, our goal was to evaluate the course of brain edema in patients with malignant MCA infarction treated with decompressive craniectomy (DC) using hemispheric volumetric measurements. METHODS: Patients were selected consecutively from a single tertiary hospital between 2013 and 2019. All patients were diagnosed with malignant middle cerebral artery infarction and underwent a decompressive craniectomy (DC) to treat the ischemic event. All computed tomography (CT) exams performed during the clinical care of these patients were analyzed, and the whole ischemic hemisphere volume was calculated for each CT scan. RESULTS: We analyzed 43 patients (197 CT exams). Patients' mean age at DC was 51.72 [range: 42-68] years. The mean time between the ischemic ictus and DC was 41.88 (range: 6-77) hours. The mean time between the ischemic event and the peak of hemisphere volume was 168.84 (95% confidence interval [142.08, 195.59]) hours. CONCLUSION: In conclusion, the peak of cerebral edema in malignant MCA infarction after DC occurred on the 7th day (168.84 h) after stroke symptoms onset. Further studies evaluating therapies for brain edema even after DC should be investigated.

ANTECEDENTES: O edema cerebral é a principal causa de morte em pacientes com infarto maligno de artéria cerebral média. O desvio da linha média tem sido utilizado como marcador de edema cerebral mono-hemisférico em alguns estudos; porém, ele não mede de forma precisa o edema cerebral. Atualmente é possível mensurar diretamente o volume do hemisfério cerebral. O conhecimento sobre a evolução temporal do edema cerebral após infartos malignos da artéria cerebral média pode contribuir para o cuidado clínico desta condição. OBJETIVO: Nosso objetivo é avaliar o edema hemisférico ao longo do tempo, em pacientes com infarto maligno da artéria cerebral média, tratados com craniectomia descompressiva. MéTODOS: Os pacientes foram selecionados de forma consecutiva, em um hospital terciário, entre 2013 e 2019. Todos os pacientes apresentavam diagnóstico de infarto maligno de artéria cerebral média e foram submetidos a craniectomia descompressiva. Todas as tomografias computadorizadas de crânio destes pacientes foram analizadas, e o volume do hemisfério cerebral infartado foi mensurado. RESULTADOS: Analisamos 43 pacientes (197 tomografias de crânio). A idade média dos pacientes na craniectomia descompressiva foi 51,72 (42­68) anos. O tempo médio entre o ictus e a craniectomia descompressiva foi 41,88 (6­77) horas. O tempo médio entre o ictus e o pico do volume hemisférico foi 168,84 (142,08­195,59) horas. CONCLUSãO: O pico do volume cerebral em pacientes com infarto maligno de artéria cerebral média submetidos a craniectomia descompressiva ocorreu no 7o dia (168,84 horas) após o infarto. Mais estudos avaliando terapêuticas direcionadas ao edema cerebral seriam úteis neste contexto.

Time course of hemispheric cerebral volume after decompressive craniectomy in malignant middle cerebral artery stroke / Evolução temporal do volume hemisférico cerebral após craniectomia descompressiva em infarto maligno de artéria cerebral média

Abstract Background Brain edema is the leading cause of death in patients with malignant middle cerebral artery (MCA) infarction. Midline shift (MLS) has been used as a monohemispheric brain edema marker in several studies; however, it does not precisely measure brain edema. It is now possible to directly measure hemisphere brain volume. Knowledge about the time course of brain edema after malignant middle cerebral artery infarction may contribute to the condition's management. Objective Therefore, our goal was to evaluate the course of brain edema in patients with malignant MCA infarction treated with decompressive craniectomy (DC) using hemispheric volumetric measurements. Methods Patients were selected consecutively from a single tertiary hospital between 2013 and 2019. All patients were diagnosed with malignant middle cerebral artery infarction and underwent a decompressive craniectomy (DC) to treat the ischemic event. All computed tomography (CT) exams performed during the clinical care of these patients were analyzed, and the whole ischemic hemisphere volume was calculated for each CT scan. Results We analyzed 43 patients (197 CT exams). Patients' mean age at DC was 51.72 [range: 42-68] years. The mean time between the ischemic ictus and DC was 41.88 (range: 6-77) hours. The mean time between the ischemic event and the peak of hemisphere volume was 168.84 (95% confidence interval [142.08, 195.59]) hours. Conclusion In conclusion, the peak of cerebral edema in malignant MCA infarction after DC occurred on the 7th day (168.84 h) after stroke symptoms onset. Further studies evaluating therapies for brain edema even after DC should be investigated.

Resumo Antecedentes O edema cerebral é a principal causa de morte em pacientes com infarto maligno de artéria cerebral média. O desvio da linha média tem sido utilizado como marcador de edema cerebral mono-hemisférico em alguns estudos; porém, ele não mede de forma precisa o edema cerebral. Atualmente é possível mensurar diretamente o volume do hemisfério cerebral. O conhecimento sobre a evolução temporal do edema cerebral após infartos malignos da artéria cerebral média pode contribuir para o cuidado clínico desta condição. Objetivo Nosso objetivo é avaliar o edema hemisférico ao longo do tempo, em pacientes com infarto maligno da artéria cerebral média, tratados com craniectomia descompressiva. Métodos Os pacientes foram selecionados de forma consecutiva, em um hospital terciário, entre 2013 e 2019. Todos os pacientes apresentavam diagnóstico de infarto maligno de artéria cerebral média e foram submetidos a craniectomia descompressiva. Todas as tomografias computadorizadas de crânio destes pacientes foram analizadas, e o volume do hemisfério cerebral infartado foi mensurado. Resultados Analisamos 43 pacientes (197 tomografias de crânio). A idade média dos pacientes na craniectomia descompressiva foi 51,72 (42-68) anos. O tempo médio entre o ictus e a craniectomia descompressiva foi 41,88 (6-77) horas. O tempo médio entre o ictus e o pico do volume hemisférico foi 168,84 (142,08-195,59) horas. Conclusão O pico do volume cerebral em pacientes com infarto maligno de artéria cerebral média submetidos a craniectomia descompressiva ocorreu no 7o dia (168,84 horas) após o infarto. Mais estudos avaliando terapêuticas direcionadas ao edema cerebral seriam úteis neste contexto.

Decompressive craniectomy index: Does the size of decompressive craniectomy matter in malignant middle cerebral artery infarction?

Background: Malignant middle cerebral artery (MCA) infarction is associated with high mortality, mainly due to intracranial hypertension. This malignant course develops when two-thirds or more of MCA territory is infarcted. Randomized clinical trials demonstrated that in patients with malignant MCA infarction, decompressive craniectomy (DC) is associated with better prognosis. In these patients, some prognostic predictors are already known, including age and time between stroke and DC. The size of bone flap was not associated with long-term prognosis in the previous studies. Therefore, this paper aims to further expand the analysis of the bone removal toward a more precise quantification and verify the prognosis implication of the bone flap area/whole supratentorial hemicranium relation in patients treated with DC for malignant middle cerebral infarcts. Methods: This study included 45 patients operated between 2015 and 2020. All patients had been diagnosed with a malignant MCA infarction and were submitted to DC to treat the ischemic event. The primary endpoint was dichotomized modified Rankin scale (mRS) 1 year after surgery (mRS≤4 or mRS>4). Results: Patients with bad prognosis (mRS 5-6) were on average: older and with a smaller decompressive craniectomy index (DCI). In multivariate analysis, with adjustments for "age" and "time" from symptoms onset to DC, the association between DCI and prognosis remained. Conclusion: In our series, the relation between bone flap size and theoretical maximum supratentorial hemicranium area (DCI) in patients with malignant MCA infarction was associated with prognosis. Further studies are necessary to confirm these findings.

Do Hippocampal Neurons Really Count for Comorbid Depression in Patients With Mesial Temporal Lobe Epilepsy and Hippocampal Sclerosis? A Histopathological Study.

Depression is the most frequent psychiatric comorbidity seen in mesial temporal lobe epilepsy (MTLE) patients with hippocampal sclerosis (HS). Moreover, the HS is the most frequent pathological hallmark in MTLE-HS. Although there is a well-documented hippocampal volumetric reduction in imaging studies of patients with major depressive disorder, in epilepsy with comorbid depression, the true role of the hippocampus is not entirely understood. This study aimed to verify if patients with unilateral MTLE-HS and the co-occurrence of depression have differences in neuronal density of the hippocampal sectors CA1-CA4. For this purpose, we used a histopathological approach. This was a pioneering study with patients having both clinical disorders. However, we found no difference in hippocampal neuronal density when depression co-occurs in patients with epilepsy. In this series, CA1 had the lowest counting in both groups, and HS ILAE Type 1 was the most prevalent. More studies using histological assessments are needed to clarify the physiopathology of depression in MTLE-HS.

Granule cell dispersion is associated with hippocampal neuronal cell loss, initial precipitating injury, and other clinical features in mesial temporal lobe epilepsy and hippocampal sclerosis.

PURPOSE: To characterize a 10-year series of patients with mesial temporal lobe epilepsy (MTLE) and unilateral hippocampal sclerosis (HS) and determine the histopathological characteristic of the association between granule cell dispersion (GCD) and hippocampal neuronal loss. METHODS: The study included 108 MTLE/HS patients. Histopathological analyses were performed in NeuN-stained hippocampal sections for HS pattern, neuronal density, dentate gyrus (DG) pathology, and granule cell layer width. Statistical tests investigated the association between DG pathologies and HS patterns, as well as the correlation of DG width with total hippocampal and subfield-specific neuronal densities. RESULTS: Fifty-six patients (51.9%) presented right HS. All the four ILAE HS patterns were represented (90 Type 1, 11 Type 2, 2 Type 3, and 5 no-HS). Sixty-seven patients (62.0%) presented GCD, 39 (36.1%) normal DG, and 2 (1.9%) narrow DG. GCD was associated with initial precipitating injury, higher numbers of monthly focal seizures and lifetime bilateral tonic-clonic seizures, longer epilepsy duration, and older age at surgery. GCD was prevalent in all HS patterns, except for Type 2 (81.8% normal versus 18.2% GCD, p = 0.005). GCD was associated with total hippocampal and subfield-specific neuronal loss, except for CA1. DG width correlated with total hippocampal (r = -0.201, p = 0.037) and CA4 neuronal densities (r = -0.299, p = 0.002). Patients with HS Type 1 had better surgical outcomes, with 51 (61.4%) seizure-free in the first year post-surgery. CONCLUSIONS: This study confirmed that seizure control in MTLE/HS patients submitted to surgical treatment is comparable worldwide. Moreover, histopathological analyses showed an association between GCD and hippocampal neuronal loss, especially in the CA4 subfield.

A pioneering FreeSurfer volumetric study of a series of patients with mesial temporal lobe epilepsy and hippocampal sclerosis with comorbid depression.

Depression is the most frequent psychiatric comorbidity in patients with mesial temporal lobe epilepsy (MTLE) and hippocampal sclerosis (HS). This study aimed to confirm whether patients with comorbid depression have different volumetric patterns on magnetic resonance imaging, analysing the influence of HS sides. Psychiatrists conducted semi-structured interviews with 75 patients, who were divided into non-depression group (NDG, n = 52) and depression group (DG, n = 23), and compared with 98 controls. The FreeSurfer software was used in the volumetric analysis of the estimated total intracranial volume (eTIV), bilateral cortical and subcortical regions of interest (ROIs), and for presence of left (L-, n = 41) or right (R-, n = 34) MTLE-HS. Twenty-three (30.7%) patients had depression, of whom 14 (34.1%) had l-MTLE-HS and 9 (26.5%) had R-MTLE-HS. No difference was observed between DG and NDG vs. controls in terms of eTIV and cortical ROIs, regardless of the severity of depression. In patients with l-MTLE-HS, the eTIV in the DG was reduced in comparison with that in the NDG and control group, with a small effect size. Hippocampal reduction occurred ipsilateral to HS in the l-MTLE-HS and R-MTLE-HS subgroups when DG and NDG were compared with controls, as expected according to Enhancing Neuro Imaging Genetics through Meta-Analysis (2018).

Efficacy and Safety of a Nasopharyngeal Catheter for Selective Brain Cooling in Patients with Traumatic Brain Injury: A Prospective, Non-randomized Pilot Study.

BACKGROUND: The efficacy objective was to determine whether a novel nasopharyngeal catheter could be used to cool the human brain after traumatic brain injury, and the safety objective was to assess the local and systemic effects of this therapeutic strategy. METHODS: This was a prospective, non-randomized, interventional clinical trial that involved five patients with severe traumatic brain injury. The intervention consisted of inducing and maintaining selective brain cooling for 24 h by positioning a catheter in the nasopharynx and circulating cold water inside the catheter in a closed-loop arrangement. Core temperature was maintained at ≥ 35 °C using counter-warming. RESULTS: In all study participants, a brain temperature reduction of ≥ 2 °C was achieved. The mean brain temperature reduction from baseline was 2.5 ± 0.9 °C (P = .04, 95% confidence interval). The mean systemic temperature was 37.3 ± 1.1 °C at baseline and 36.0 ± 0.8 °C during the intervention. The mean difference between the brain temperature and the systemic temperature during intervention was - 1.2 ± 0.8 °C (P = .04). The intervention was well tolerated with no significant changes observed in the hemodynamic parameters. No relevant variations in intracranial pressure and transcranial Doppler were observed. The laboratory results underwent no major changes, aside from the K+ levels and blood counts. The K+ levels significantly varied (P = .04); however, the variation was within the normal range. Only one patient experienced an event of mild localized and superficial nasal discoloration, which was re-evaluated on the seventh day and indicated complete recovery. CONCLUSION: The results suggest that our noninvasive method for selective brain cooling, using a novel nasopharyngeal catheter, was effective and safe for use in humans.

Neurocysticercosis and pharmacoresistant epilepsy: possible role of calcified lesions in epileptogenesis.

Neurocysticercosis is a neglected and usually poverty-related disease of high public importance. The mechanisms by which the calcified lesions cause epilepsy are not known, but have been attributed to residual perilesional gliosis or an inflammatory process. This case shows that an inflammatory response to a calcified granuloma may be associated with the development of epilepsy. The increase in glutamate and kinin B1 (pro-epileptogenic) receptors added by reduced expression of kinin B2 (anti-epileptogenic) receptors may explain the chronic epileptogenesis associated with the lesion, corroborating the hypothesis of inflammatory mechanisms involved in the pathophysiology of epilepsy in these patients.

Intraoperative Ultrasound Using Dorsal Root Entry Zone Lesioning: A Way to Guide Intraspinal Cord Therapeutic Lesions.

Dorsal root entry zone (DREZ) lesioning is an effective method to treat refractory neuropathic pain in patients with radicular avulsion. In this procedure, we penetrate the spinal cord with a radiofrequency electrode using the posterior lateral sulcus as a guide. The intraspinal electrode trajectory has to be angled medially about 25°-45° to spare the corticospinal tract, which lies lateral to the DREZ, and also to spare the posterior column, which lies medial to it. Here we present a case of a patient with radicular avulsion lesion of rootlets of the cervical spinal cord successfully treated with DREZ lesioning using intraoperative ultrasound as a guide to perform the spinal cord lesions. The use of intraoperative ultrasound during DREZ lesioning in patients with radicular avulsion improves the neurosurgeon ability to precisely localize the posterior lateral sulcus and also to better define the correct angulation of the trajectory.

Microsurgical Treatment of Ruptured Spetzler-Martin Grade 3 Right Hippocampal Arteriovenous Malformation: 3-Dimensional Operative Video.

We present a 14-yr-old male with a history of traumatic brain injury in March 2016, secondary to clonic tonic generalized seizures. CT scan showed hemorrhage at mesial temporal region in the body of right hippocampus, intraventricular hemorrhage at the level of lateral ventricles (right and left side) and fourth ventricle. After this the patient presented with pulsating right temporal headache of high intensity (VAS 10/10) that improved with common analgesics, dizziness, and clonic tonic generalized seizures despite taking Phenobarbital 100 mg/24 h. Neuropsychological assessment reveal major deficits regarding executive functions: working memory, verbal fluency, and planning abilities. Brain MRI and angiography showed AVM at the right level of hippocampus body. An intranidal aneurysm was also observed. Venous drainage was through the basal vein of Rosenthal. We planned for surgery and resection of the hippocampal AVM through the trans-T2 approach. Postoperatively, the patient was without medical complications. We present a 3-dimensional video of the microsurgical treatment for right hippocampal AVM performed through a trans-T2 approach. The patient signed the Institutional Consent Form, which allows the use of his/her images and videos for any type of medical publications in conferences and/or scientific articles.

Effects of a brief psychotherapeutic intervention on resilience and behavior in patients with drug-resistant mesial temporal lobe epilepsy and late seizure recurrence after surgery.

Seizure recurrence (SR) after epilepsy surgery in patients with medically resistant temporal lobe epilepsy and mesial temporal sclerosis (TLE-MTS) can compromise medical treatment and quality of life (QOL). However, there is a scarcity of interventions specifically addressing this issue in the literature. We aimed to evaluate the impact of a four-week psychotherapeutic intervention on the levels of resilience, behavioral symptoms, and QOL of patients with drug-resistant TLE-MTS who underwent corticoamygdalohippocampectomy (CAH) and who presented with late SR. Fifty patients who had been diagnosed with TLE-TMS, undergone CAH, and presented with late SR were included. The study instruments included a clinical and sociodemographic questionnaire and the Brazilian versions of the Connor-Davidson Resilience Scale (CD-RISC-10), the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E), the Interictal Dysphoric Disorder Inventory (IDDI), and the Quality of Life in Epilepsy Inventory (QOLIE-31). Significant reductions in the IDDI (p < 0.001) and NDDI-E (p < 0.001) scores, improvements in the CD-RISC-10 (p < 0.001) and QOLIE-31 (p < 0.001) scores, and positive correlations between resilience levels and QOL (p < 0.01), as well as a negative correlation between depressive symptoms and resilience (p < 0.01) and QOL (p < 0.01), were observed after the psychotherapeutic intervention. Improvements in the resilience levels and QOL, with concomitant reductions in depressive symptoms, were observed in patients with TLE-MTS and late SR after a brief psychotherapeutic intervention. Since there is a lack of studies that measured the impact of interventions in this patient subpopulation, these results may support the development of treatment strategies for this specific group.

Revisiting personality in epilepsy: Differentiation of personality in two epilepsies starting in adolescence.

PURPOSE: The purpose of this study was to investigate personality characteristics and clinical parameters in two well-defined epilepsies: mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE/HS) and juvenile myoclonic epilepsy (JME) through NEO Revised Personality Inventory (NEO-PI-R) and Neurobehavior Inventory (NBI) standardized instruments. METHODS: One hundred patients undergoing corticoamygdalohippocampectomy (CAH), 100 patients with JME, and 100 control subjects answered the personality measures. Clinical parameters such as psychiatric symptoms, seizure frequency, duration of epilepsy, and side of the lesion in MTLE/HS group were investigated. Statistical analysis consisted of the mean and standard deviation (SD) of each variable. Student's t-test or Fisher exact test were used according to the variable studied. RESULTS: The three groups were within the average range of NEO-PI-R and NBI, although 'tendencies' and differences were demonstrated. The MTLE/HS and control subjects had a similar profile: low scores in Neuroticism and high in Conscientiousness (r = -0.330; p < 0.001/r = -0.567; p < 0.001, respectively) in opposition to what occurred in JME, low in Conscientiousness and high in Neuroticism (r = -0.509; p = 0.005). The NBI 'sense of personal destiny' trait was higher (3.15; p = 0.003) in MTLE/HS than in JME and controls. The JME 'law and order' scores were lower than in other groups (p = 0.024). A tendency towards specific NBI traits differentiates MTLE/HS (Factor 3) from JME (Factor 1) groups. Psychiatric symptoms and seizure frequency were correlated with worse scores in NBI and, especially, in Neuroticism domain of NEO-PI-R. CONCLUSION: Specific personality features were linked to each epileptic disease. These findings highlight the importance of considering unique features linked to epilepsy conditions in daily clinical observation to develop support programmes.

Transtentorial Approach for Parahippocampal Gyrus Arteriovenous Malformation Resection: 3-Dimensional Operative Video.

Medial temporal basal arteriovenous malformations (AVMs) have complex anatomy. They usually drain to the basal vein of Rosenthal, and arterial feeders can arise from the anterior choroidal artery and its branches, or from the posterior cerebral artery. If the AVM is more posterior in the parahippocampal gyrus, there is a predominance of arterial feeders arising from P2P or P3 segments of the posterior cerebral artery. As posterior AVMs are difficult to reach using anterior approaches, the supracerebellar transtentorial approach provides a direct pathway to the malformation, allowing better visualization and exposure of the vascular anatomy. In this video, we present a 29-yr-old woman with a left parahippocampal AVM with P2P arterial feeders and Rosenthal basal vein drainage. The patient had three months of moderate headache and two abrupt seizures before admission. Emergency computed tomography showed intraventricular hemorrhage. Magnetic resonance imaging and cerebral angiography revealed an AVM located in the parahippocampal gyrus, posterior to pulvinar thalamus. The patient underwent microsurgical treatment in semi-sitting position using a supracerebellar and infratentorial approach with transtentorial resection. The AVM was completely removed, and the patient recovered without neurological deficits. The authors present a 3-dimensional video of the microsurgical steps required to perform a transtentorial approach for AVM resection in the parahippocampal gyrus. The patient signed the Institutional Consent Form, which allows the use of his/her images and videos for any type of medical publications in conferences and/or scientific articles.

The impact of epilepsy duration in a series of patients with mesial temporal lobe epilepsy due to unilateral hippocampal sclerosis.

PURPOSE: To evaluate if the duration of epilepsy influences MRI volumes of the hippocampus, amygdala, parahippocampal gyrus, entorhinal cortex and temporal pole of both hemispheres and epileptogenic hippocampus neuronal cell density and dentate gyrus granular cells distribution in patients with refractory mesial temporal lobe epilepsy due to hippocampal sclerosis (MTLE/HS). METHODS: Seventy-seven patients with refractory MTLE/HS submitted to surgery were included. Histopathological analysis included: (1) quantitative: hippocampal subfields and total estimated hippocampal cell density (HCD), thickness of the dentate gyrus - normal, thinning or dispersion; (2) qualitative: type of HS and granule cells pathology in the dentate gyrus (normal, neuronal cell loss, dispersion and bilamination). Automated MRI-derived measurements from bilateral temporal structures (hippocampus, amygdala, parahippocampal gyrus, temporal pole, entorhinal cortex) were obtained for 58 subjects. Histopathological and imaging findings were compared with data from specimens obtained in autopsies of age-matched individuals and living controls, respectively, and the data were adjusted for the age at epilepsy onset and the frequency of focal impaired awareness seizures/month. RESULTS: Forty-two (54.5%) patients presented right HS. The greater the duration of epilepsy, the smaller the total estimated HCD (p = 0.025; r = -0.259). Patients with a normal distribution of the granular cells had a shorter epilepsy duration than those with dispersion (p = 0.018) or thinning (p = 0.031). A reduced ipsilateral hippocampal volume (r = -0.551, p = 0.017) and a smaller hippocampal asymmetry index (r = -0.414, p = 0.002) were correlated to a longer epilepsy duration. The estimated HCD was correlated to the volume of the ipsilateral hippocampus (r = 0.420, p = 0.001). CONCLUSION: Our study showed an increasing atrophy of the ipsilateral hippocampus in patients with a longer epilepsy duration. Our data suggest that this reduction in hippocampal volume is related to neuronal loss. Besides that, we also showed an increased probability of exhibiting an abnormal distribution of the granular cells in the dentate gyrus in patients with longer epilepsy duration.

Morphometric MRI features and surgical outcome in patients with epilepsy related to hippocampal sclerosis and low intellectual quotient.

OBJECTIVE: The objectives of this study were to verify in a series of patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) if those with low intellectual quotient (IQ) levels have more extended areas of atrophy compared with those with higher IQ levels and to analyze whether IQ could be a variable implicated on a surgical outcome. MATERIAL AND METHODS: Patients (n=106) with refractory MTLE-HS submitted to corticoamygdalohippocampectomy (CAH) (57 left mesial temporal lobe epilepsy (MTLE); 45 males) were enrolled. To determine if the IQ was a predictor of seizure outcome, totally seizure-free (SF) versus nonseizure-free (NSF) patients were evaluated. FreeSurfer was used for cortical thickness and volume estimation, comparing groups with lower (<80) and higher IQ (90-109) levels. RESULTS: In the whole series, 42.45% of patients were SF (Engel Class 1a; n=45), and 57.54% were NSF (n=61). Total cortical volume was significantly reduced in the group with lower IQ (p=0.01). Significant reductions in the left hemisphere included the following: rostral middle frontal (p=0.001), insula (p=0.002), superior temporal gyrus (p=0.003), thalamus (p=0.004), and precentral gyrus (p=0.02); and those in the right hemisphere included the following: rostral middle frontal (p=0.003), pars orbitalis (p=0.01), and insula (p=0.02). Cortical thickness analysis also showed reductions in the right superior parietal gyrus in patients with lower IQ. No significant relationship between IQ and seizure outcome was found. CONCLUSIONS: This is the first study of a series of patients with pure MTLE-HS, including those with low IQ and their morphometric magnetic resonance imaging (MRI) features using FreeSurfer. Although patients with lower intellectual scores presented more areas of brain atrophy, IQ was not a predictor of surgical outcome. Therefore, when evaluating seizure follow-up, low IQ in patients with MTLE-HS might not contraindicate resective surgery.