Clinical outcomes after medial temporal lobe epilepsy surgery: Anterior temporal lobectomy versus selective amygdalohippocampectomy / 中南大学学报(医学版)

Objective:To compare the anterior temporal lobectomy (ATL) with transsylvian selective amygdalohippocampectomy (SeAH) in 72 patients with medial temporal lobe epilepsy (MTLE) regarding the seizure control and neuropsychological outcomes.Methods:Clinical data and follow-up data were collected and retrospectively analyzed.SeAH and ATL were used in 39 and 33 patients,respectively.All eligible patients were followed up at least one year.Wechsler Adult Intelligence Scale-Revised and the Wechsler Memory Scale-Revised were used to test the patients' neuropsychology before and after the surgery for one year.Results:Fifty-nine patients (81.9％) achieved satisfactory seizure control (62.5％ Engel Class Ⅰ and 19.4％ Class Ⅱ).ATL obtained 84.8％ satisfactory seizure control (28 patients),and the success rate was 79.5％ (31 patients) for SeAH.There was no significant difference in seizure control between SeAH and ATL (P=0.760).The postoperative verbal IQ of SeAH group increased significantly in both side surgery (P＜0.05),while the increase was not significant in the group of ATL of both side surgery (P＞0.05).Regarding left-side surgery,postoperative verbal memory and total memory were increased significantly in the group of SeAH (P＜0.05),while the increases were not significant in the group ofATL (P＞0.05).In the right-side surgery,postoperative verbal memory and total memory were increased significantly in the two surgery strategy groups (P＜0.05),while no significant increases were seen in non-verbal memory of the two surgery strategy groups (P＞0.05).Conclusion:Microsurgery for the treatment of refractory MTLE is successful and safe,and should be encouraged.The seizure outcome is not different between ATL and SeAH,while regarding as verbal IQ and verbal memory outcomes,SeAH may be superior to ATL in dominant hemisphere surgery.

Preliminary investigation on memory outcomes following selective amygdalohippocampectomy versus anterior temporal lobectomy for temporal lobe epilepsy and hippocampal sclerosis / 中国神经精神疾病杂志

Objective To investigate the different memory outcomes in temporal lobe epilepsy patients underwent different surgical approaches.Methods Two hundred forty-eight patients with temporal lobe epilepsy and hippocampal scle-rosis underwent standard anterior temporal lobectomy ( ATL, n=83 ) or selective amygdalohippocampectomy ( SAH, n=165) from 2009 to 2013.All the patients underwent clinical memory function assessment before surgery, 3 months and 2 years after surgery respectively.Results The memory quotient ( MQ) of patients who underwent brain surgery in the domi-nant hemisphere significantly decreased 3 months after surgery (74.5 ±16.2, 75.6 ±19.5) compared to presurgery MQ (82.9 ±15.8, 83.2 ±21.2) in both ATL and SAH groups (P<0.05).Although MQ was slightly recovered at 2 years af-ter surgery, MQ (75.1 ±14.1, 76.1 ±17.6) was still significantly lower compared with presurgery MQ (P<0.05).A-mong this, both the decrease extent of the MQ 3 months after surgery and 2 years after surgery were smaller in the SAH group than in the ATL group (7.6 vs.8.4;7.1 vs.7.8).The MQ of patients who underwent brain surgery in the non-dominant hemisphere (either ATL or SAH ) increased slightly 3 months after surgery (87.2 ±15.1, 88.1 ±16.9) com-pared to presurgery MQ (85.5 ±13.5, 85.3 ±19.7) although the difference was not statistically significant.The MQ of these two groups improved significantly 2 years after surgery (92.8 ±12.7, 93.7 ±17.1)(P<0.05).The improvement extent of the MQ was larger in the SAH group than in the ATL group (8.4 vs.7.3).Conclusions SAH may be better than ATL in the maintenance of memory function in patients with temporal lobe epilepsy and hippocampal sclerosis.

Anatomia microcirúrgica do hipocampo na Amígdalo-hipocampectomia seletiva sob a perspectiva da técnica de Niemeyer e método pré-operatório para maximizar a corticotomia / Hippocampal microsurgical anatomy regarding the selective amygdalohippocampectomy in the Niemeyer’s technique perspective and preoperative method to maximize the corticotomy

O conhecimento da anatomia microcirúrgica do hipocampo tem importância fundamental na cirurgia da epilepsia do lobo temporal. Uma das técnicas mais utilizadas na cirurgia da epilepsia é a técnica de Niemeyer. OBJETIVO: Descrever em detalhes a anatomia do hipocampo e mostrar uma técnica na qual pontos de referências anatômicos pré-operatórios visualizados na RNM são usados para guiar a corticotomia. MÉTODO: Foram utilizados 20 hemisférios cerebrais e 8 cadáveres para dissecções anatômicas microcirúrgicas do lobo temporal e hipocampo para identificação e descrição das principais estruturas do hipocampo. Foram estudados prospectivamente 32 pacientes com epilepsia do lobo temporal refratários ao tratamento clínico submetidos a amígdalo-hipocampectomia seletiva pela técnica de Niemeyer três parâmetros anatômicos foram mensurados na RNM pré operatória e transferidos para o ato cirúrgico. RESULTADOS: O hipocampo foi dividido em cabeça, corpo e cauda e sua anatomia microcirúrgica descrita em detalhes. As medidas adquiridas são apresentadas e discutidas. CONCLUSÃO: A complexa anatomia do hipocampo pode ser entendida de uma forma tridimensional durante dissecções microcirúrgicas. As medidas pré-operatórias mostraram-se guias anatômicos úteis para corticotomia na técnica de Niemeyer.

The deep knowledge of hippocampal microsurgical anatomy is paramount in epilepsy surgery. One of the most used techniques is those proposed by Niemeyer. PURPOSE: To describe the hippocampal anatomy in details and to present a technique which preoperative anatomical points in MRI are identified to guide the corticotomy. METHOD: Microsurgical dissections were performed in twenty brain hemispheres and eight cadaveric heads to identify temporal lobe and hippocampus structures. Thirty two patients with drug-resistent temporal lobe epilepsy underwent a selective amygdalohippocampectomy with Niemeyer’s technique being measured three preoperative MRI preoperative distances to guide the corticotomy. RESULTS: The hippocampus was divided in head, body and tail and its microsurgical anatomy described in details. The MRI measurements are presented and discussed. CONCLUSION: The knowledge of the complex anatomy of the hippocampus can be achieved in a three-dimensional way during microsurgical dissections not. The preoperative MRI measurement is a reasonable guide to perform temporal corticotomy in Niemeyer’s techinique.

Magnetic Resonance Imaging Anatomy for Surgical Application in Subtemporal Selective Amygdalohippocampectomy

Although subtemporal amygdalohippocampectomy is the ideal approach for pure mesial temporal lobe epilepsy from the view point that it can resect amygdala, hippocampusis, and parahippocampal gyrus selectively, this approach has not gained wide popularity due to shortcomings such as temporal lobe retraction and possible injury to temporal lobe draining veins. We analized surgical anatomy on MRI scan of 20 persons for the purpose of modifing the subtemporal approach to overcome the inherent shortcomings. The distance from temporal pole to anterior margin of temporal horn was 29.8+/-5mm(range, 28.5-31mm). Anterior margin of hippocampus was located 1.8+/-9mm(range, 1-3mm) anterior to dorsum sella. The length of hippocampus to the level of posterior margin of cerebral peduncle was 25.6+/-4mm. External auditary meatus divided the hippocampus, from anterior to the level of posterior margin of cerebral peduncle, in the ratio of 1.52: 1. On the coronal image through interpeduncular cistern, the distance between lateral margin of temporal lobe and collateral sulcus was 40.6+/-.3mm(37-45mm). On the coronal image through interpeduncular cistern and through the external auditary meatus, the height from temporal base to the choroidal fissure was 30.0+/-.7mm and 21.3+/-.5mm, respectively, and the angle between temporal base line and a line from collateral sulcus to choroidal fissure was 45.7+/-.6 degree and 33.2+/-.9 degree, respectively. In conclusion, our results indicate that external auditary meatus(EAM) is anatomical landmark for subtemporal amygdalohippocampectomy, and skull base approach focused on either EAM or anterior to EAM is necessary to minimize morbidity due to temporal lobe retraction and draining vein injury.