Summary
Objective
Hippocampal sclerosis is a common finding in patients with temporal lobe epilepsy (TLE), and magnetic resonance imaging (MRI) studies associate the reduction of hippocampal volume ...with the neuron loss seen on histologic evaluation. Astrogliosis and increased levels of chondroitin sulfate, a major component of brain extracellular matrix, are also seen in hippocampal sclerosis. Our aim was to evaluate the association between hippocampal volume and chondroitin sulfate, as well as neuronal and astroglial populations in the hippocampus of patients with TLE.
Methods
Patients with drug‐resistant TLE were subdivided, according to hippocampal volume measured by MRI, into two groups: hippocampal atrophy (HA) or normal volume (NV) cases. Hippocampi from TLE patients and age‐matched controls were submitted to immunohistochemistry to evaluate neuronal population, astroglial population, and chondroitin sulfate expression with antibodies against neuron nuclei protein (NeuN), glial fibrillary acidic protein (GFAP), and chondroitin sulfate (CS‐56) antigens, respectively.
Results
Both TLE groups were clinically similar. NV cases had higher hippocampal volume, both ipsilateral and contralateral, when compared to HA. Compared to controls, NV and HA patients had reduced neuron density, and increased GFAP and CS‐56 immunopositive area. There was no statistical difference between NV and HA groups in neuron density or immunopositive areas for GFAP and CS‐56. Hippocampal volume correlated positively with neuron density in CA1 and prosubiculum, and with immunopositive areas for CS‐56 in CA1, and negatively with immunopositive area for GFAP in CA1. Multiple linear regression analysis indicated that both neuron density and CS‐56 immunopositive area in CA1 were statistically significant predictors of hippocampal volume.
Significance
Our findings indicate that neuron density and chondroitin sulfate immunopositive area in the CA1 subfield are crucial for the hippocampal volume, and that chondroitin sulfate is important for the maintenance of a normal hippocampal volume in some cases with severe neuron loss.
Abstract Patients with left mesial temporal lobe epilepsy (MTLE) have deficits in verbal memory processes, while patients with right MTLE have visuospatial memory impairment. However, atypical ...cognitive phenotypes among patients with MTLE may occur. In this study, we analyzed preoperative memory deficits in a cohort of 426 right-handed patients with unilateral MTLE. We also evaluated the cognitive outcome after anterior temporal lobectomy (ATL) of patients with atypical profiles in comparison with those with typical memory profile. We found that 25% of our patients had a typical cognitive profile, with verbal memory deficits associated with left side hippocampal sclerosis (HS) and visuospatial memory deficits associated with right side HS. However, 75% of our patients had atypical memory profiles. Despite these atypical profiles, patients submitted to right ATL had no significant cognitive deficit after surgery. In patients submitted to left ATL, the higher the presurgical scores on verbal memory and naming tests, the higher the cognitive decline after surgery.
Temporal lobe epilepsy (TLE) is the most common form of partial epilepsy and affects 40% of the patients. Seizures arising from the mesial temporal lobe structures (i.e., amygdala and hippocampus) ...are common, whereas neocortical seizures are rare. In recent years, many studies aimed to identify the pattern of gene expression of neurotransmitters involved in molecular mechanisms of epilepsy. We used real-time PCR to quantify the expression of GABA(A) (subunits α1, β1, β2) and NMDA (subunits NR1, NR2A, and NR2B) receptor genes in amygdalae of 27 patients with TLE and 14 amygdalae from autopsy controls. The NR1 subunit was increased in patients with epilepsy when compared with controls. No differences were found in expression of NMDA subunits NR2A and NR2B or in α1, β1, and β2 subunits of GABA(A) receptors. Our results suggest that the NR1 subunit of NMDA receptors is involved in the amygdala hyperexcitability in some of the patients with TLE.
Central nervous system synapses have an intrinsic plastic capacity to adapt to new conditions with rapid changes in their structure. Such activity‐dependent refinement occurs during development and ...learning, and shares features with diseases such as epilepsy. Quantitative ultrastructural studies based on serial sectioning and reconstructions have shown various structural changes associated with synaptic strength involving both dendritic spines and postsynaptic densities (PSDs) during long‐term potentiation (LTP). In this review, we focus on experimental studies that have analyzed at the ultrastructural level the consequences of LTP in rodents, and plastic changes in the hippocampus of experimental models of epilepsy and human tissue obtained during surgeries for intractable temporal lobe epilepsy (TLE). Modifications in spine morphology, increases in the proportion of synapses with perforated PSDs, and formation of multiple spine boutons arising from the same dendrite are the possible sequence of events that accompany hippocampal LTP. Structural remodeling of mossy fiber synapses and formation of aberrant synaptic contacts in the dentate gyrus are common features in experimental models of epilepsy and in human TLE. Combined electrophysiological and ultrastructural studies in kindled rats and chronic epileptic animals have indicated the occurrence of seizure‐ and neuron loss‐induced changes in the hippocampal network. In these experiments, the synaptic contacts on granule cells are similar to those described for LTP. Such changes could be associated with enhancement of synaptic efficiency and may be important in epileptogenesis.
Abstract The objectives of the study were to translate and adapt the Subjective Handicap of Epilepsy (SHE) instrument to Brazilian Portuguese and to determine its psychometric properties for the ...evaluation of quality of life in patients with epilepsy. A sample of 448 adult patients with epilepsy with different clinical profiles (investigation, preoperative period, postoperative period, and drug treatment follow-up) was evaluated with the SHE and the Epilepsy Surgery Inventory (ESI-55). Exploratory factorial analysis demonstrated that four factors explained 60.47% of the variance and were sensitive to discriminate the different clinical groups, with the preoperative group having the poorest quality of life. Internal consistency ranged from 0.92 to 0.96, and concurrent validity with the ESI-55 was moderate/strong (0.32–0.70). Test–retest reliability was confirmed, with an ICC value of 0.54 (2 days), 0.91 (7 days), and 0.97 (30 days). The SHE had satisfactory psychometric qualities for use in the Brazilian population, similar to those of the original version. The instrument seems to be more adequate in psychometric terms for the postoperative and drug treatment follow-up groups, and its use should be encouraged.
Summary
Purpose: To evaluate the clinical and hippocampal histological features of patients with mesial temporal lobe epilepsy (MTLE) in both familial (FMTLE) and sporadic (SMTLE) forms.
Methods: ...Patients with FMTLE (n = 20) and SMTLE (n = 39) who underwent surgical treatment for refractory seizures were studied at the University of São Paulo School of Medicine at Ribeirão Preto. FMTLE was defined when at least two individuals in a family had clinical diagnosis of MTLE. Hippocampi from all patients were processed for Nissl/HE and Timm's stainings. Both groups were compared for clinical variables, hippocampal cell densities, and intensity of supragranular mossy fiber staining.
Results: There were no significant differences between FMTLE and SMTLE groups in the following: age at the surgery, age of first usual epileptic seizure, history of initial precipitating injury (IPI), age of IPI, latent period, ictal and interictal video‐EEG patterns, presence of hippocampal atrophy and signal changes at MRI, and postoperative outcome. In addition, no differences were found in cell densities in hippocampal cornu ammonis subfields (CA1, CA2, CA3, CA4), fascia dentata, polymorphic region, subiculum, prosubiculum, and presubiculum. However, patients with SMTLE had greater intensity of mossy fiber Timm's staining in the fascia dentata‐inner molecular layer (p< 0.05).
Discussion: Patients with intractable FMTLE present a clinical profile and most histological findings comparable to patients with SMTLE. Interestingly, mossy fiber sprouting was less pronounced in patients with FMTLE, suggesting that, when compared to SMTLE, patients with FMTLE respond differently to plastic changes plausibly induced by cell loss, neuronal deafferentation, or epileptic seizures.
Abstract Psychiatric co-morbidities in epilepsy are common in patients with temporal lobe epilepsy (TLE). Pathological alterations in TLE are well characterised; however, neuropathologic data are ...relatively scale regarding the association between psychiatric diseases and epilepsy. Our objective was to evaluate the clinical data of 46 adult TLE patients with and without psychiatric co-morbidities and to correlate the data with hippocampal neuronal density and mossy fiber sprouting. Accordingly, patients were grouped as follows: TLE patients without history of psychiatric disorder (TLE, n = 16), TLE patients with interictal psychosis (TLE + P, n = 14), and TLE patients with major depression (TLE + D, n = 16). Hippocampi from autopsies served as non-epileptic controls ( n = 10). TLE + P exhibited significantly diminished mossy fiber sprouting and decreased neuronal density in the entorhinal cortex when compared with TLE. TLE + P showed significantly poorer results in verbal memory tasks. TLE + D exhibited significantly increased mossy fiber sprouting length when compared with TLE and TLE + P. Further, a higher proportion of TLE + D and TLE + P presented secondarily generalised seizures than did TLE. Our results indicate that TLE patients with psychiatric disorders have distinct features when compared with TLE patients without psychiatric co-morbidities and that these changes may be involved in either the manifestation or the maintenance of psychiatric co-morbidities in epilepsy.
Tentorial meningiomas comprise 3–5% of the intracranial meningiomas. Different locations and sinus invasion require special surgical skills. This study aimed to analyze factors influencing the ...outcome of 29 patients (30 tumors) with tentorial meningiomas surgically treated. The study included 22 female and seven male patients, with age of 18–76 years old, and a follow-up of 6–179 months. Eight tumors were located on the inner tentorial ring, 15 on the outer ring, four were falcotentorial, and three attached/invading the torcula. Outcome was analyzed using survival and recurrence-free survival (RFS) curves. Twenty-seven tumors were WHO grade I and three were grades II–III. Total and subtotal resections were reached in 87.5% and 12.5% of tumors. Survival was better for patients with grade I tumors and similar according to sex, location, size, and extent of resection. Recurrence/regrowing rate was 12.5%. RFS curves were better for patients with grade I or with radical resection and similar according to sex, location, and size. There was no operative mortality. Permanent postoperative cranial nerve deficits occurred in 9.7% (all inner ring tumors). Despite being many times large-sized, surgical treatment of tentorial meningiomas gives good results. Prognostic factors for recurrence were histopathologic grade III and subtotal resection. Radical resection allowed better results. Nevertheless, subtotal resection may be acceptable for cases with cranial nerves or sinuses invasions.
Purpose: To characterize perfusion patterns of periictal single‐photon emission tomography (SPECT) in patients with unilateral temporal lobe epilepsy (TLE) and to determine their relationship to the ...epileptogenic zone (EZ).
Methods: We studied periictal SPECT scans of 53 patients after anterior mesial temporal lobectomy who had good seizure outcome after surgery. Ictal SPECT scans were performed during video‐EEG monitoring. Typical SPECT patterns consisted of ipsilateral ictal hyperperfusion or ipsilateral postictal hypoperfusion. Atypical ictal patterns included normal scans, bilateral temporal hyperperfusion, or contralateral patterns. These perfusion patterns were retrospectively analyzed searching for concordance rate with the EZ.
Results: We obtained 51 ictal and two early postictal scans. In the typical group, 40 (75.4%) patients had ipsilateral ictal temporal lobe hyperperfusion, and one (1.9%) patient had ipsilateral postictal temporal lobe hypoperfusion. Twelve (22.7%) patients exhibited atypical perfusion patterns: seven (13.2%) patients had bitemporal ictal hyperperfusion (four cases showed asymmetric temporal lobe changes), four (7.6%) patients had contralateral hyperperfusion, and one (1.9%) patient had a normal SPECT scan. All four patients with bitemporal asymmetric hyperperfusions showed greater perfusion lateralized to the side of the EZ. Three of the four patients who had contralateral hyperperfusion also had a complex postictal‐like pattern in the ipsilateral temporal lobe consisting of anteromesial hyperperfusion with adjacent lateral hypoperfusion.
Conclusions: This study analyzed typical and atypical perfusion patterns in unilateral TLE, and suggested that not only typical, but also some atypical perfusion patterns may contribute to the lateralization of EZ.
Olfactory groove meningiomas comprise 4-10% of the intracranial meningiomas. Generally they give signs of brain compression due to great size they reach before diagnosis. In this study, the clinical ...outcome of patients with olfactory groove meningiomas surgically treated was analyzed.
17 patients operated on from 1988-2006. Female: 16, Male: 1. Age: 19-76 years-old (mean=53.12 +/- 13.11).
1-209 months (mean=51.07 +/- 12.73. Bifrontal/bifrontal-bi-orbital approaches were used. Outcome was analyzed using survival/recurrence-free Kaplan-Mayer curves.
16 had WHO grade 1; one grade 2 meningiomas. Resection Simpson's grade 1 was in achieved in 64.7%, grade 2 in 29.4% and grade 3 in 5.9%. There was no recurrence during the follow-up. Global and operative mortality were 11.8%. Main postoperative complications were osteomyelitis (11.8%) and pneumonia (5.9%).
Extensive approaches allowed total resection of most olfactory groove meningiomas with no recurrence during the follow-up, but operative mortality and local complications were high.
PDF
