What is the best age for surgery in drug-resistant mesial temporal lobe epilepsy?

Object Hippocampal sclerosis can be identified in most patients with mesial temporal lobe epilepsy (TLE). Surgical removal of the sclerotic hippocampus is widely performed to treat patients with drug-resistant mesial TLE. In general, both epilepsy-prone and epilepsy-resistant neurons are believed to be in the hippocampal formation. The hilar mossy cells of the hippocampal dentate gyrus are usually considered one of the most vulnerable types of neurons. The aim of this study was to clarify the fate of mossy cells in the hippocampus in epileptic humans. Methods Of the 19 patients included in this study, 15 underwent temporal lobe resection because of drug-resistant TLE. Four patients were used as controls because they harbored tumors that had not invaded the hippocampus and they had experienced no seizures. Histological evaluation of resected hippocampal tissues was performed using immunohistochemistry. Results Mossy cells were identified in the control as well as the epileptic hippocampi by using cocaine- and amphetamine-regulated transcript peptide immunohistochemistry. In most cases the number of mossy cells was reduced and thorny excrescences were smaller in the epileptic hippocampi than in controls; however, there was a significant loss of pyramidal cells and a partial loss of granule cells in the same epileptic hippocampi in which mossy cell loss was apparent. The loss of mossy cells could be correlated with the extent of hippocampal sclerosis, patient age at seizure onset, duration of epilepsy, and frequency of seizures. Conclusions In many cases large numbers of mossy cells were present in the hilus of the dentate gyrus when most pyramidal neurons of the CA1 and CA3 areas of the Ammon's horn were lost, suggesting that mossy cells may not be more vulnerable to epileptic seizures than the hippocampal pyramidal neurons.

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Ictal fear is associated with anxiety symptoms and interictal dysphoric disorder in drug-resistant mesial temporal lobe epilepsy

Epilepsy & Behavior ◽

10.1016/j.yebeh.2020.107548 ◽

2021 ◽

Vol 115 ◽

pp. 107548

Author(s):

Hiago Murilo Melo ◽

Ricardo Guarnieri ◽

Helena Dresch Vascouto ◽

Douglas Afonso Formolo ◽

Cristiane Ribeiro de Carvalho ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Mesial Temporal Lobe Epilepsy ◽

Anxiety Symptoms ◽

Drug Resistant ◽

Mesial Temporal Lobe

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Multiple hippocampal transections for mesial temporal lobe epilepsy

Surgical Neurology International ◽

10.25259/sni_350_2021 ◽

2021 ◽

Vol 12 ◽

pp. 372

Author(s):

David Pitskhelauri ◽

Elina Kudieva ◽

Maria Kamenetskaya ◽

Antonina Kozlova ◽

Pavel Vlasov ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Verbal Memory ◽

Visual Memory ◽

Focal Cortical Dysplasia ◽

Mesial Temporal Lobe Epilepsy ◽

Drug Resistant ◽

Preoperative Level ◽

Temporal Pole ◽

Mesial Temporal Lobe

Background: The purpose of this study was to evaluate the effectiveness of multiple hippocampal transections (MHT) in the treatment of drug-resistant mesial temporal lobe epilepsy. Methods: Six patients underwent MHT at Burdenko Neurosurgery Center in 2018. The age of the patients varied from 18 to 43 years. All patients suffered from refractory epilepsy caused by focal lesions of the mesial temporal complex or temporal pole in dominant side. Postoperative pathology revealed neuronal-glial tumors in two patients, focal cortical dysplasia (FCD) of the temporal pole – in two patients, cavernous angioma – in one patient, and encephalocele of the preuncal area – in one patient. Results: All patients underwent surgery satisfactorily. There were no postoperative complications except for homonymous superior quadrantanopia. This kind of visual field loss was noted in four cases out of six. During the follow-up period five patients out of six had Engel Class I outcome (83.3%). In one case, seizures developed after 1 month in a patient with FCD in the uncus (Engel IVA). After surgery, three out of six patients developed significant nominative aphasia. Two patients relative to the preoperative level demonstrated improvement in delayed verbal memory after MHT. Two patients showed a decrease level in delayed verbal memory. In preoperative period, visual memory was below the normal in one patient. Delayed visual memory in two cases impaired compared to the preoperative level. Conclusion: MHT can be considered as an effective method of drug-resistant mesial temporal lobe epilepsy caused by tumors of the medial temporal complex. At the same time, MHT makes it possible to preserve memory in patients with structurally preserved hippocampus. However, MHT do not guarantee the preservation of memory after surgery.

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Efficacy of limited hippocampal radiofrequency thermocoagulation for mesial temporal lobe epilepsy

Journal of Neurosurgery ◽

10.3171/2018.4.jns184 ◽

2019 ◽

Vol 131 (3) ◽

pp. 781-789 ◽

Cited By ~ 1

Author(s):

Ching-Yi Lee ◽

Han-Tao Li ◽

Tony Wu ◽

Mei-Yun Cheng ◽

Siew-Na Lim ◽

...

Keyword(s):

Adverse Effects ◽

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Seizure Frequency ◽

Seizure Control ◽

Mesial Temporal Lobe Epilepsy ◽

Temporary Increase ◽

Drug Resistant ◽

Radiofrequency Thermocoagulation ◽

Mesial Temporal Lobe

OBJECTIVERadiofrequency thermocoagulation (RFTC), which has been developed for drug-resistant epilepsy patients, involves less brain tissue loss due to surgery, fewer surgical adverse effects, and generally good seizure control. This study demonstrates the effectiveness of RFTC performed at limited hippocampal locations.METHODSDaily seizure diaries were prospectively maintained for at least 6 months by 9 patients (ages 30–59 years) with drug-resistant mesial temporal lobe epilepsy (MTLE) before treatment with RFTC. The limited target for stereotactic RFTC was chosen based on intraoperative electroencephalography (EEG) recording and was initially tested with a Radionics electrode at a low temperature, 45°C, for 60 seconds. The therapeutic RFTC heating parameters were 78°C–80°C for 90 seconds. All patients who received the RFTC treatment underwent both MRI and EEG recording immediately postoperatively and at the 3-month follow-up. Monthly outpatient clinic visits were arranged over 6 months to document seizure frequency and severity to clarify the changes noted in imaging studies and EEG patterns.RESULTSTwo patients were excluded from our analysis because one had undergone multiple seizure surgeries and the other had a poor recording of seizure frequency, before the RFTC surgery. Five and two patients underwent left-sided and right-sided RFTC, respectively. None of the patients had generalized tonic-clonic attacks postoperatively, and no adverse effects or complications occurred. According to MRI data, the effect of coagulation was limited to less than 1.0 cm in diameter and perifocal edema was also in limited range. The seizure frequency within 6 months decreased postoperatively with a mean reduction in seizures of 78% (range 36%–100%). Only two patients had a temporary increase in seizure frequency within 2 weeks of the surgery, and over 50% of all patients showed a decrease in average seizure frequency.CONCLUSIONSThe study results confirm that limited RFTC provides a more effective surgery with similar seizure control but fewer complications than resective surgery for drug-resistant MTLE patients.

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