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Mukaino T. [Memory impairments in temporal lobe epilepsy]. Rinsho Shinkeigaku 2024:cn-001886. [PMID: 38910118 DOI: 10.5692/clinicalneurol.cn-001886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
Temporal lobe epilepsy is known to present with various cognitive impairments, among which memory deficits are frequently reported by patients. Memory deficits can be classified into two types: classical hippocampal amnesia, which is characterized by abnormalities detected in neuropsychological assessments, and atypical memory deficits, such as accelerated long-term amnesia and autobiographical memory impairment, which cannot be identified using standard testing methods. These deficits are believed to arise from a complex interplay among structural brain abnormalities, interictal epileptic discharges, pharmacological factors, and psychological states. While fundamental treatments are limited, there are opportunities for interventions such as environmental adjustments and rehabilitation. This review article aims to provide a comprehensive overview of the types, underlying pathophysiology, and intervention methods for memory disorders observed in patients with temporal lobe epilepsy.
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Dahal R, Tamura K, Sasaki R, Takeshima Y, Matsuda R, Yamada S, Nishimura F, Nakagawa I, Park YS, Nakase H. Left Temporal Pole Encephalocele With Independent Hippocampal Seizures: Surgical Strategy and Relevance of Epileptic Biomarkers. J Clin Neurophysiol 2023; 40:e646-e650. [PMID: 36930243 DOI: 10.1097/wnp.0000000000001005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
Abstract
SUMMARY Temporal pole encephalocele (TE) is an increasingly recognized surgically treatable subtype of refractory temporal lobe epilepsy that rarely shows hippocampal involvement. A 27-year-old patient presented with medically intractable epilepsy because of a left temporal pole encephalocele with a normal hippocampus on MRI. Extraoperative electrocorticography showed independent seizure onset with distinct morphology of seizure onset pattern from the temporal pole encephalocele and hippocampus. Additional analysis of ictal and interictal fast ripples revealed different electrophysiological fast ripple profiles in the two seizure onset zones. The patient underwent temporopolar disconnection, eliminating the need for large dural repair and multiple hippocampal transections that helped preserve the intrahippocampal and extrahippocampal memory pathways. Herein, the authors report that independent hippocampal seizures can be observed in patients with temporal pole encephalocele. Features of the ictal and interictal fast ripples can differ depending on the morphology of the seizure onset pattern. The authors suggest that, the interpretation of fast ripples in clinical practice should take seizure onset patterns into consideration.
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Affiliation(s)
- Riju Dahal
- Department of Neurosurgery, Nara Medical University, Kashihara, Japan
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Ueda T, Iimura Y, Mitsuhashi T, Suzuki H, Miao Y, Nishioka K, Tamrakar S, Matsui R, Tanaka T, Otsubo H, Sugano H, Kondo A. Chronological changes in phase-amplitude coupling during epileptic seizures in temporal lobe epilepsy. Clin Neurophysiol 2023; 148:44-51. [PMID: 36796285 DOI: 10.1016/j.clinph.2023.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 12/25/2022] [Accepted: 01/19/2023] [Indexed: 02/08/2023]
Abstract
OBJECTIVE To analyze chronological changes in phase-amplitude coupling (PAC) and verify whether PAC analysis can diagnose epileptogenic zones during seizures. METHODS We analyzed 30 seizures in 10 patients with mesial temporal lobe epilepsy who had ictal discharges with preictal spiking followed by low-voltage fast activity patterns on intracranial electroencephalography. We used the amplitude of two high-frequency bands (ripples: 80-200 Hz, fast ripples: 200-300 Hz) and the phase of three slow wave bands (0.5-1 Hz, 3-4 Hz, and 4-8 Hz) for modulation index (MI) calculation from 2 minutes before seizure onset to seizure termination. We evaluated the accuracy of epileptogenic zone detection by MI, in which a combination of MI was better for diagnosis and analyzed patterns of chronological changes in MI during seizures. RESULTS MIRipples/3-4 Hz and MIRipples/4-8 Hz in the hippocampus were significantly higher than those in the peripheral regions from seizure onset. Corresponding to the phase on intracranial electroencephalography, MIRipples/3-4 Hz decreased once and subsequently increased again. MIRipples/4-8 Hz showed continuously high values. CONCLUSIONS Continuous measurement of MIRipples/3-4 Hz and MIRipples/4-8 Hz could help identify epileptogenic zones. SIGNIFICANCE PAC analysis of ictal epileptic discharges can help epileptogenic zone identification.
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Affiliation(s)
- Tetsuya Ueda
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Yasushi Iimura
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Takumi Mitsuhashi
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Hiroharu Suzuki
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Yao Miao
- Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan.
| | - Kazuki Nishioka
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Samantha Tamrakar
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Ryousuke Matsui
- Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan.
| | - Toshihisa Tanaka
- Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan.
| | - Hiroshi Otsubo
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan; Division of Neurology, The Hospital for Sick Children, Toronto, ON, Canada.
| | - Hidenori Sugano
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
| | - Akihide Kondo
- Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
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Abe D, Inaji M, Hashimoto S, Takagi S, Maehara T. Epilepsy surgery for dominant-side mesial temporal lobe epilepsy without hippocampal sclerosis. J Clin Neurosci 2023; 111:16-21. [PMID: 36921552 DOI: 10.1016/j.jocn.2023.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/21/2023] [Accepted: 02/24/2023] [Indexed: 03/14/2023]
Abstract
Although anterior temporal lobectomy (ATL) is an established surgery for medically intractable mesial temporal lobe epilepsy (MTLE), it can harm memory function, especially in dominant-side MTLE patients without hippocampal sclerosis (HS). To avoid this complication, multiple hippocampal transection (MHT) was developed, but its efficacy has not been fully elucidated. We report the detailed treatment results of MHT compared with that of ATL. We retrospectively analysed the records of 30 patients who underwent surgery for dominant-side MTLE. ATL was completed for 23 patients with HS, and MHT was completed for 7 patients without HS. The seizure control status, number of anti-seizure medicines, neurocognitive function, and psychiatric disorders of each patient were reviewed. The mean follow-up period was 70 months. Seizure control of Engel class I was achieved in 16 patients (70%) in the ALT group versus 5 patients (71%) in the MHT group. The mean number of anti-seizure medicines administered in the ATL group changed significantly from 2.4 to 1.9 (p = 0.01), while that in the MHT group was unchanged (from 2.1 to 2.0, p = 0.77). Eleven patients (48%) in the ATL group developed psychiatric disorders during the postoperative follow-up period, whereas no psychological complications were observed in the MHT group. Neither group showed neurocognitive decline after the surgery in any of the WAIS-III or WMS-R subtests. In conclusion, MHT may achieve reasonable postoperative seizure reduction, preserve neurocognitive function, and reduce postoperative psychiatric complications. Therefore, it can be considered as a therapeutic option for dominant-side MTLE without HS.
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Affiliation(s)
- Daisu Abe
- Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Motoki Inaji
- Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan.
| | - Satoka Hashimoto
- Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shunsuke Takagi
- Department of Psychiatry and Behavioral Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Taketoshi Maehara
- Department of Neurosurgery, Tokyo Medical and Dental University, Tokyo, Japan
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Pak S, Jang D, Lee J, Choi G, Shin H, Yang S, Yang S. Hippocampal interlamellar cell-cell connectome that counts. J Cell Physiol 2022; 237:4037-4048. [PMID: 36063532 PMCID: PMC9826151 DOI: 10.1002/jcp.30868] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/28/2022] [Accepted: 08/23/2022] [Indexed: 01/11/2023]
Abstract
The hippocampus is regarded as a cognition hub, particularly for learning and memory. Previously, neuronal mechanisms underlying various cognitive functions are delineated with the lamellar hippocampal circuitry, dentate gyrus-CA3 or CA2-CA1, within the transverse plane. More recently, interlamellar (often referred to as longitudinal) projections have received intensive attention to help understand signal convergence and divergence in cognition and behavior. Signal propagation along the longitudinal axis is evidenced by axonal arborization patterns and synaptic responses to electro- and photo-stimulation, further demonstrating that information flow is more enriched in the longitudinal plane than the transverse plane. Here, we review the significance of longitudinal connections for cognition, discuss a putative circuit mechanism of place coding, and suggest the reconceptualization of the hippocampal circuitry.
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Affiliation(s)
- Sojeong Pak
- Department of NeuroscienceCity University of Hong KongKowloonHong Kong SAR
| | - Doohyeong Jang
- Department of Nano‐BioengineeringIncheon National UniversityIncheonSouth Korea
| | - Jinho Lee
- Department of Nano‐BioengineeringIncheon National UniversityIncheonSouth Korea
| | - Gona Choi
- Department of NeuroscienceCity University of Hong KongKowloonHong Kong SAR
| | - Hongseong Shin
- Department of Nano‐BioengineeringIncheon National UniversityIncheonSouth Korea
| | - Sungchil Yang
- Department of NeuroscienceCity University of Hong KongKowloonHong Kong SAR
| | - Sunggu Yang
- Department of Nano‐BioengineeringIncheon National UniversityIncheonSouth Korea
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Abramov I, Jubran JH, Houlihan LM, Park MT, Howshar JT, Farhadi DS, Loymak T, Cole TS, Pitskhelauri D, Preul MC. Multiple hippocampal transection for mesial temporal lobe epilepsy: A systematic review. Seizure 2022; 101:162-176. [PMID: 36041364 DOI: 10.1016/j.seizure.2022.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 08/02/2022] [Accepted: 08/19/2022] [Indexed: 11/28/2022] Open
Abstract
PURPOSE Multiple hippocampal transection (MHT) is a surgical technique that offers adequate seizure control with minimal perioperative morbidity. However, there is little evidence available to guide neurosurgeons in selecting this technique for use in appropriate patients. This systematic review analyzes patient-level data associated with MHT for intractable epilepsy, focusing on postoperative seizure control and memory outcomes. METHODS The systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant articles were identified from 3 databases (PubMed, Medline, Embase) up to August 1, 2021. Inclusion criteria were that the majority of patients had received a diagnosis of intractable epilepsy, the article was written in English, MHT was the primary procedure, and patient-level metadata were included. RESULTS Fifty-nine unique patients who underwent MHT were identified across 11 studies. Ten (17%) of 59 patients underwent MHT alone. Forty-three (75%) of 57 patients who had a follow-up 12 months or longer were seizure free at last follow-up. With respect to postoperative verbal memory retention, 9 of 38 (24%) patient test scores did not change, 14 (37%) decreased, and 16 (42%) increased. With respect to postoperative nonverbal memory retention, 12 of 38 (34%) patient test scores did not change, 13 (34%) decreased, and 13 (33%) increased. CONCLUSION There are few reported patients analyzed after MHT. Although the neurocognitive benefits of MHT are unproven, this relatively novel technique has shown promise in the management of seizures in patients with intractable epilepsy. However, structured trials assessing MHT in isolation are warranted.
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Affiliation(s)
- Irakliy Abramov
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - Jubran H Jubran
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - Lena Mary Houlihan
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - Marian T Park
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - Jacob T Howshar
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - Dara S Farhadi
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - Thanapong Loymak
- Department of Neurosurgery, Srisawan Hospital, Nakhonsawan, Thailand
| | - Tyler S Cole
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ
| | - David Pitskhelauri
- Department of Neuro-Oncology, Burdenko Neurosurgical Center, Moscow, Russia
| | - Mark C Preul
- The Loyal and Edith Davis Neurosurgical Research Laboratory, Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ.
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Hasegawa D, Saito M, Kitagawa M. Neurosurgery in canine epilepsy. Vet J 2022; 285:105852. [PMID: 35716888 DOI: 10.1016/j.tvjl.2022.105852] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 05/24/2022] [Accepted: 06/10/2022] [Indexed: 11/18/2022]
Abstract
Epilepsy surgery is functional neurosurgery applied to drug-resistant epilepsy. Although epilepsy surgery has been established and achieves fair to good outcomes in human medicine, it is still an underdeveloped area in veterinary medicine. With the spread of advanced imaging and neurosurgical modalities, intracranial surgery has become commonplace in the veterinary field, and, therefore, it is natural that expectations for epilepsy surgery increase. This review summarizes current standards of intracranial epilepsy surgery in human medicine and describes its current status and expectation in veterinary medicine. Intracranial epilepsy surgery is classified generally into resection surgery, represented by cortical resection, lobectomy, and lesionectomy, and disconnection surgery, such as corpus callosotomy and multiple subpial transection. In dogs with drug-resistant epilepsy, corpus callosotomy is available as a disconnection surgery for generalized epilepsy. However, other types of disconnection and resection surgeries for focal epilepsy are limited to experimental studies in laboratory dogs and/or anecdotal case reports of lesionectomy, such as tumor or encephalocele removal, without epileptogenic evidence. Veterinary epilepsy surgery is a new and challenging neurosurgery field; with the development of presurgical evaluations such as advanced electroencephalography and neuroimaging, it may become more readily practiced.
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Affiliation(s)
- Daisuke Hasegawa
- Laboratory of Veterinary Radiology, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan; The Research Center for Animal Life Science, Nippon Veterinary and Life Science University, 1-7-1 Kyounancho, Musashino, Tokyo 180-8602, Japan.
| | - Miyoko Saito
- Laboratory of Small Animal Surgery (Neurology), School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Sagamihara, Kanagawa 252-5201, Japan
| | - Masato Kitagawa
- Laboratory of Veterinary Neurology, Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa, Kanagawa 252-0880, Japan
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Kozlova A, Korsakova M, Pitskhelauri D, Kudieva E, Dombaanai B, Vlasov P, Kamenetskaya M. Neurophysiological aspects of multiple hippocampal transection in intractable temporal lobe epilepsy. Zh Nevrol Psikhiatr Im S S Korsakova 2022; 122:104-111. [DOI: 10.17116/jnevro2022122011104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Pitskhelauri D, Kudieva E, Kamenetskaya M, Kozlova A, Vlasov P, Dombaanai B, Eliseeva N, Shishkina L, Sanikidze A, Shults E, Moshev D, Pronin I, Melikyan A. Multiple hippocampal transections for mesial temporal lobe epilepsy. Surg Neurol Int 2021; 12:372. [PMID: 34513139 PMCID: PMC8422472 DOI: 10.25259/sni_350_2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/25/2021] [Indexed: 11/16/2022] Open
Abstract
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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Affiliation(s)
- David Pitskhelauri
- Department of Neurosurgery, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Elina Kudieva
- Department of Neurosurgery, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Maria Kamenetskaya
- Department of Neuropsychiatric Research, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Antonina Kozlova
- Department of Neurophysiological Research, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Pavel Vlasov
- Department of Pediatric Neurosurgery, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Baiyr Dombaanai
- Department of Neurosurgery, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Natalia Eliseeva
- Department of Neuroophthalmological Research, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Lyudmila Shishkina
- Department of Neuropathology, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Alexander Sanikidze
- Department of Neurosurgery, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Evgeniy Shults
- Department of X-ray and Radioisotope Research, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Dmitriy Moshev
- Department of Neuroanesthesiology, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Igor Pronin
- Department of X-ray and Radioisotope Research, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
| | - Armen Melikyan
- Department of Pediatric Neurosurgery, Burdenko National Medical Research Center of Neurosurgery, Moscow, Russia
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Marashly A, Koop J, Loman M, Kim I, Maheshwari M, Lew SM. Multiple hippocampal transections for refractory pediatric mesial temporal lobe epilepsy: seizure and neuropsychological outcomes. J Neurosurg Pediatr 2020; 26:379-388. [PMID: 32590352 DOI: 10.3171/2020.4.peds19760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/13/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Temporal lobe epilepsy (TLE) is the most common focal epilepsy across adult and pediatric age groups. It is also the most amenable to surgery, with excellent long-term seizure outcome. Most TLE cases have an epileptogenic zone in the mesial temporal structures, namely the hippocampus. Resecting the dominant hippocampus has been shown to be associated with significant verbal memory deficits, especially in patients with intact verbal memory scores presurgically. Multiple hippocampal transection (MHT) is a relatively new surgical technique designed to interrupt the longitudinal hippocampal circuitry involved in seizure propagation yet preserve the circular fibers involved in memory function. This technique has been used to treat mesial TLE in both dominant- and nondominant-hemisphere cases, almost exclusively in adults. It has been applied to normal and sclerotic hippocampi. METHODS In this study, information on 3 pediatric patients who underwent MHT for mesial TLE at Children's Wisconsin between 2017 and 2018 is included. Clinical, electroencephalographic, and neuropsychological features and outcomes are described in detail. RESULTS MRI revealed a tumor in the amygdala with a normal hippocampus in 1 patient and hippocampal sclerosis in 2 patients. All patients underwent stereoelectroencephalography confirming the involvement of the hippocampus in seizure onset. MHTs were completed under intraoperative monitoring, with amygdala and temporal tip resection in all patients due to early spread to these regions. All patients had excellent seizure outcomes at 1 year, and 2 of the 3 patients remain seizure free at last follow-up (range 20-36 months), all with stable or improved neuropsychological profiles, including verbal memory. CONCLUSIONS MHT is a relatively new surgical procedure designed to preserve essential memory circuitry while disrupting seizure propagation pathways in the hippocampus. A growing body of literature shows good seizure and neuropsychological results, but mainly in adults. This is the first series of MHTs used exclusively in children at one medical center, showcasing excellent seizure control and preservation of neuropsychological functioning. One of the patients is also the first described to have MHT in the setting of an amygdalar tumor abutting the hippocampus, further expanding the pathological setting in which MHT can be used effectively.
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Affiliation(s)
- Ahmad Marashly
- 1Division of Pediatric Neurology, University of Washington/Seattle Children's Hospital, Seattle, Washington; and
| | | | | | | | - Mohit Maheshwari
- 4Pediatric Radiology, Children's Wisconsin/Medical College of Wisconsin, Milwaukee, Wisconsin
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Warsi N, Thiong'o GM, Zuccato J, Ibrahim GM. Multiple hippocampal transections: Post-operative Memory Outcomes and Seizure Control. Epilepsy Behav 2019; 100:106496. [PMID: 31654940 DOI: 10.1016/j.yebeh.2019.106496] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/11/2019] [Accepted: 08/14/2019] [Indexed: 11/30/2022]
Abstract
OBJECT Temporal lobectomy with amygdalohippocampectomy is the standard surgical treatment for appropriate candidates with medically-intractable temporal lobe epilepsy. More recently, because of the risk of postoperative language/memory decline in a subset of patients with intact memory, a multiple hippocampal transection (MHT) approach has been proposed to preserve function. METHODS Studies of MHT reporting both Engel and verbal memory outcome measures were included in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for reporting of systematic reviews. Data were extracted on verbal memory function pre- and postoperatively, seizure outcome, and demographic factors. A random effects model was used to determine overall verbal memory function after MHT, and a meta-regression model was applied to identify factors associated with outcome. RESULTS A total of 114 patients across five studies were included. Engel class I seizure outcome across all studies ranged from 64.7% to 94.7%, with 84 of the 114 patients achieving this outcome. Preoperative verbal memory score was most strongly associated with postoperative verbal memory preservation (p = 0.003). Of 59 patients with full verbal memory outcome scores, 86.8% (95% CI [confidence interval]: 77.6%-96%) had complete preservation of verbal memory relative to preoperative functional baseline. CONCLUSION Multiple hippocampal transection is an evolving surgical technique. Although the present data are limited, the current systematic review suggests that this approach is effective at preserving verbal memory in patients with good baseline function. Although reasonable seizure outcomes have been reported with MHT, comparison to a well-established procedure such as temporal lobectomy and amydalohippocampectomy must be guided by further evidence.
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Affiliation(s)
- Nebras Warsi
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Grace M Thiong'o
- Division of Neurosurgery, The Hospital for Sick Children, Department of Surgery, University of Toronto, Toronto, Canada
| | - Jeff Zuccato
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - George M Ibrahim
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
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Park JT, Fernandez Baca Vaca G, Tangen R, Miller J. Hippocampal transection for stereo-electroencephalography-proven dominant mesial temporal lobe epilepsy in a child: a detailed case report and critical review. J Neurosurg Pediatr 2018; 22:1-7. [PMID: 30095344 DOI: 10.3171/2018.5.peds1896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/15/2018] [Indexed: 11/06/2022]
Abstract
Resection of the hippocampus ipsilateral to the verbal memory-dominant hemisphere frequently results in severe memory deficits. In adults with epilepsy, multiple hippocampal transections (MHTs) have resulted in excellent seizure outcome with preservation of verbal memory. The authors report the first detailed case of a child undergoing MHTs for mesial temporal lobe epilepsy. A 13-year-old right-handed boy had intractable seizures characterized by epigastric discomfort evolving to unresponsiveness and chewing automatisms, lasting 1 minute and occurring 2-3 times weekly, sometimes ending in a generalized tonic-clonic seizure. He had no seizure risk factors and nonfocal examination results. Interictal electroencephalography (EEG) showed frequent left temporal epileptiform discharges (maximum FT9) and intermittent slowing. Video EEG, FDG-PET, and 1.5-T MRI were nonlocalizing. Neuropsychological evaluation suggested left temporal lobe dysfunction. A stereo-EEG investigation using 8 electrodes localized the seizure onset zone to the anterior mesial temporal region, immediately involving the hippocampus. The temporal pole and amygdala were resected en bloc with 3 MHTs. Comparison of neuropsychological tests 4 months before and 6 months after the surgery showed a significant decline only in confrontational naming and no significant change in verbal memory. Six and a half years later, the patient remains seizure free with no antiepileptic drugs. In children with established hemispheric dominance suffering from mesial temporal lobe epilepsy, MHTs may be an option.
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Affiliation(s)
- Jun T Park
- 1Section of Pediatric Epilepsy, Department of Pediatrics, Rainbow Babies & Children's Hospital, Case Western University School of Medicine.,2Epilepsy Center, Neurological Institute, Department of Neurology, University Hospital, Case Western University School of Medicine
| | - Guadalupe Fernandez Baca Vaca
- 2Epilepsy Center, Neurological Institute, Department of Neurology, University Hospital, Case Western University School of Medicine
| | - Rachel Tangen
- 3Division of Developmental and Behavioral Pediatrics and Psychology, Department of Pediatrics, Rainbow Babies & Children's Hospital, Case Western University School of Medicine; and
| | - Jonathan Miller
- 4Department of Neurosurgery, Neurological Institute, University Hospital, Case Western University School of Medicine, Cleveland, Ohio
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Uda T, Kunihiro N, Nakajo K, Kuki I, Fukuoka M, Ohata K. Seizure freedom from temporal lobe epilepsy with mesial temporal lobe tumor by tumor removal alone without hippocampectomy despite remaining abnormal discharges on intraoperative electrocorticography: Report of two pediatric cases and reconsideration of the surgical strategy. Surg Neurol Int 2018; 9:181. [PMID: 30283714 PMCID: PMC6157038 DOI: 10.4103/sni.sni_61_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 08/09/2018] [Indexed: 11/24/2022] Open
Abstract
Background: In the surgical treatment of temporal lobe epilepsy with mesial temporal lobe tumor, whether to remove the hippocampus aiming for a better seizure outcome in addition to removing the tumor is a dilemma. Two pediatric cases treated successfully with tumor removal alone are presented. Case Description: The first case was an 11-year-old girl with a ganglioglioma in the left uncus, and the second case was a 9-year-old girl with a pleomorphic xanthoastrocytoma in the left parahippocampal gyrus. In both cases, the hippocampus was not invaded, merely compressed by the tumor. Tumor removal was performed under intraoperative electrocorticography (ECoG) monitoring. After tumor removal, abnormal discharges remained at the hippocampus and adjacent temporal cortices, but further surgical interventions were not performed. The seizures disappeared completely in both cases. Conclusions: When we must decide whether to remove the hippocampus, the side of the lesion, the severity and chronicity of the seizures, and the presence of invasion to the hippocampus are the factors that should be considered. Abnormal discharges on ECoG at the hippocampus or adjacent cortices are one of the factors related to epileptogenicity, but it is simply a result of interictal irritation, and it is not an absolute indication for additional surgical intervention.
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Affiliation(s)
- Takehiro Uda
- Department of Neurosurgery, Osaka City University Graduate School of Medicine, Osaka, Japan.,Department of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan
| | - Noritsugu Kunihiro
- Department of Pediatric Neurosurgery, Osaka City General Hospital, Osaka, Japan
| | - Kosuke Nakajo
- Department of Neurosurgery, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Ichiro Kuki
- Department of Pediatric Neurology, Osaka City General Hospital, Osaka, Japan
| | - Masataka Fukuoka
- Department of Pediatric Neurology, Osaka City General Hospital, Osaka, Japan
| | - Kenji Ohata
- Department of Neurosurgery, Osaka City University Graduate School of Medicine, Osaka, Japan
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Ishida W, Morino M, Matsumoto T, Casaos J, Ramhmdani S, Lo SFL. Hippocampal Transection Plus Tumor Resection as a Novel Surgical Treatment for Temporal Lobe Epilepsy Associated with Cerebral Cavernous Malformations. World Neurosurg 2018; 119:e209-e215. [PMID: 30064030 DOI: 10.1016/j.wneu.2018.07.108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/11/2018] [Accepted: 07/12/2018] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The optimal surgical treatment for cavernous malformation-related temporal lobe epilepsy (CRTLE) is still controversial because it frequently involves the hippocampus as an epileptogenic zone. Here we describe our unique surgical strategy of performing hippocampal transection (HT) plus tumor resection for CRTLE to solve the question of how to balance postoperative seizure outcomes and neuropsychologic outcomes. METHODS From 2005 to 2016, 7 cases of HT (3 on dominant side) plus tumor resection were performed for patients with CRTLE. We routinely perform intraoperative electrocorticography just before and after the resection of the tumor with hemosiderin rim. In cases with residual spikes from the hippocampus after the resection, we add HT, considering laterality of the lesion, preoperative memory functions, and magnetic resonance imaging abnormalities in hippocampi. Patient information, including seizure outcomes and preoperative and postoperative (24 months) Wechsler Memory Scale-Revised (WMS-R), were collected. RESULTS In the mean follow-up of 62.7 months (range 20-119), the postoperative seizure outcome was as follows: Engel class I in 6 cases (85.7%) and II in 1 case (14.3%). Perioperative changes in WMS-R score were as follows: 93.5 preoperatively versus 99.5 postoperatively (P = 0.408) in verbal memory and 90.7 versus 98.0 (P = 0.351) in delayed recall. Overall, no patient presented with more than 25% decline in any of the WMS-R indices postoperatively. CONCLUSIONS Despite the small sample size and noncontrolled study design, postoperative seizure outcomes were deemed acceptable with favorable memory outcomes, which rather improved postoperatively with marginal statistical significance. In patients with CRTLE, additional HT is a reasonable treatment option.
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Affiliation(s)
- Wataru Ishida
- Department of Neurosurgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA.
| | - Michiharu Morino
- Department of Neurosurgery, Kumagaya General Hospital, Kumagaya, Japan
| | | | - Joshua Casaos
- Department of Neurosurgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Seba Ramhmdani
- Department of Neurosurgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Sheng-Fu Larry Lo
- Department of Neurosurgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
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Sun DG, Kang H, Tetteh H, Su J, Lee J, Park SW, He J, Jo J, Yang S, Yang S. Long term potentiation, but not depression, in interlamellar hippocampus CA1. Sci Rep 2018; 8:5187. [PMID: 29581468 PMCID: PMC5979950 DOI: 10.1038/s41598-018-23369-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 03/12/2018] [Indexed: 01/23/2023] Open
Abstract
Synaptic plasticity in the lamellar CA3 to CA1 circuitry has been extensively studied while interlamellar CA1 to CA1 connections have not yet received much attention. One of our earlier studies demonstrated that axons of CA1 pyramidal neurons project to neighboring CA1 neurons, implicating information transfer along a longitudinal interlamellar network. Still, it remains unclear whether long-term synaptic plasticity is present within this longitudinal CA1 network. Here, we investigate long-term synaptic plasticity between CA1 pyramidal cells, using in vitro and in vivo extracellular recordings and 3D holography glutamate uncaging. We found that the CA1-CA1 network exhibits NMDA receptor-dependent long-term potentiation (LTP) without direction or layer selectivity. By contrast, we find no significant long-term depression (LTD) under various LTD induction protocols. These results implicate unique synaptic properties in the longitudinal projection suggesting that the interlamellar CA1 network could be a promising structure for hippocampus-related information processing and brain diseases.
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Affiliation(s)
- Duk-Gyu Sun
- Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju, Korea
| | - Hyeri Kang
- Department of Nano-bioengineering, Incheon National University, Incheon, Korea
| | - Hannah Tetteh
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Junfeng Su
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Jihwan Lee
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Sung-Won Park
- Department of Nano-bioengineering, Incheon National University, Incheon, Korea
| | - Jufang He
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Jihoon Jo
- Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju, Korea. .,Department of Neurology, Chonnam National University Medical School, Gwangju, Korea. .,NeuroMedical Convergence Laboratory, Biomedical Research Institute, Chonnam National University Hospital, Gwangju, Korea.
| | - Sungchil Yang
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong.
| | - Sunggu Yang
- Department of Nano-bioengineering, Incheon National University, Incheon, Korea.
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Ogawa H, Hiroshima S, Kamada K. Left hippocampectomy in an epilepsy patient with right hemisphere language dominance. COGENT MEDICINE 2017. [DOI: 10.1080/2331205x.2017.1364029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Hiroshi Ogawa
- Department of Neurosurgery, Asahikawa Medical University, 2-1, Midorigaoka-Higashi, Asahikawa, Hokkaido, 078-8510, Japan
| | - Satoru Hiroshima
- Department of Neurosurgery, Asahikawa Medical University, 2-1, Midorigaoka-Higashi, Asahikawa, Hokkaido, 078-8510, Japan
| | - Kyousuke Kamada
- Department of Neurosurgery, Asahikawa Medical University, 2-1, Midorigaoka-Higashi, Asahikawa, Hokkaido, 078-8510, Japan
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Girgis F, Greil ME, Fastenau PS, Sweet J, Lüders H, Miller JP. Resection of Temporal Neocortex During Multiple Hippocampal Transections for Mesial Temporal Lobe Epilepsy Does not Affect Seizure or Memory Outcome. Oper Neurosurg (Hagerstown) 2017; 13:711-717. [DOI: 10.1093/ons/opx031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 01/31/2017] [Indexed: 11/12/2022] Open
Abstract
Abstract
BACKGROUND
Multiple hippocampal transection (MHT) is a surgical treatment for mesial temporal lobe epilepsy associated with improved postoperative neuropsychological outcomes compared with lobectomy.
OBJECTIVE
To determine whether resection of the amygdala and anterior temporal neocortex during MHT affects postoperative seizure/memory outcome.
METHODS
Seventeen patients with normal magnetic resonance imaging and stereo-electroencephalogram-proven drug-resistant dominant mesial temporal lobe epilepsy were treated with MHT. Nine patients underwent MHT alone (MHT–) and 8 patients underwent MHT plus removal of the amygdala and anterior 4.5 cm of temporal neocortex lateral to the fusiform gyrus (MHT+). Verbal and visual-spatial memory were assessed in all patients preoperatively and in 14 patients postoperatively using the Wechsler Memory Scale. Postoperative seizure control was assessed at 12 months for all patients.
RESULTS
Overall, 11 of 17 patients (64.7%) were Engel class 1 at 1 year (6/9 MHT–, 5/8 MHT+, P = .38), and 10 of 14 patients (71.4%) had no significant postoperative decline in either verbal or visual memory (6/8 MHT–, 4/6 MHT+, P = .42). Verbal memory declined in 2 of 8 MHT– and 1 of 6 MHT+ patients, and visual memory declined in 1 of 8 MHT– and 2 of 6 MHT+ patients. Two patients had improved visual memory postoperatively, both in the MHT+ group.
CONCLUSION
MHT on the dominant side is associated with high rates of seizure freedom and favorable memory preservation outcomes regardless of the extent of neocortical resection. Preservation of the temporal neocortex and amygdala during MHT does not appear to decrease the risk of postoperative memory decline, nor does it alter seizure outcome.
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Affiliation(s)
- Fady Girgis
- Department of Neurosurgery, University Hospital Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Madeline E Greil
- Department of Neurosurgery, University Hospital Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Philip S Fastenau
- Department of Neurology, University Hospital Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Jennifer Sweet
- Department of Neurosurgery, University Hospital Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Hans Lüders
- Department of Neurology, University Hospital Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Jonathan P Miller
- Department of Neurosurgery, University Hospital Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio
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Koubeissi MZ, Kahriman E, Fastenau P, Bailey C, Syed T, Amina S, Miller J, Munyon C, Tanner A, Karanec K, Tuxhorn I, Lüders H. Multiple hippocampal transections for intractable hippocampal epilepsy: Seizure outcome. Epilepsy Behav 2016; 58:86-90. [PMID: 27064827 DOI: 10.1016/j.yebeh.2016.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 02/29/2016] [Accepted: 03/04/2016] [Indexed: 01/19/2023]
Abstract
PURPOSE The purpose of this study was to evaluate the seizure outcomes after transverse multiple hippocampal transections (MHTs) in 13 patients with intractable TLE. METHODS Thirteen patients with normal memory scores, including 8 with nonlesional hippocampi on MRI, had temporal lobe epilepsy (TLE) necessitating depth electrode implantation. After confirming hippocampal seizure onset, they underwent MHT. Intraoperative monitoring was done with 5-6 hippocampal electrodes spaced at approximately 1-cm intervals and spike counting for 5-8min before each cut. The number of transections ranged between 4 and 7. Neuropsychological assessment was completed preoperatively and postoperatively for all patients and will be reported separately. RESULTS Duration of epilepsy ranged between 5 and 55years. There were no complications. Intraoperatively, MHT resulted in marked spike reduction (p=0.003, paired t-test). Ten patients (77%) are seizure-free (average follow-up was 33months, range 20-65months) without medication changes. One of the 3 patients with persistent seizures had an MRI revealing incomplete transections, another had an additional neocortical seizure focus (as suggested by pure aphasic seizures), and the third had only 2 seizures in 4years, one of which occurred during antiseizure medication withdrawal. Verbal and visual memory outcomes will be reported separately. Right and left hippocampal volumes were not different preoperatively (n=12, p=0.64, Wilcoxon signed-rank test), but the transected hippocampal volume decreased postoperatively (p=0.0173). CONCLUSIONS Multiple hippocampal transections provide an effective intervention and a safe alternative to temporal lobectomy in patients with hippocampal epilepsy.
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Affiliation(s)
| | - Emine Kahriman
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | - Philip Fastenau
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | | | - Tanvir Syed
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | - Shahram Amina
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | - Jonathan Miller
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | - Charles Munyon
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | | | | | - Ingrid Tuxhorn
- University Hospitals Case Medical Center, Cleveland, OH, United States
| | - Hans Lüders
- University Hospitals Case Medical Center, Cleveland, OH, United States
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Usami K, Kubota M, Kawai K, Kunii N, Matsuo T, Ibayashi K, Takahashi M, Kamada K, Momose T, Aoki S, Saito N. Long-term outcome and neuroradiologic changes after multiple hippocampal transection combined with multiple subpial transection or lesionectomy for temporal lobe epilepsy. Epilepsia 2016; 57:931-40. [PMID: 27080062 DOI: 10.1111/epi.13374] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Multiple hippocampal transection (MHT) is a surgical procedure developed to avoid postoperative memory decline. Its efficacy has been documented in only a few small series with relatively short observation periods. We prospectively evaluated the long-term seizure and cognitive outcomes of MHT combined with multiple subpial transection or lesionectomy (MHT + MST/L). Moreover, we quantitatively evaluated the structural and metabolic neuroradiologic changes after the procedure to elucidate the anatomofunctional correlates of memory preservation. METHODS Twenty-four patients underwent MHT + MST/L for treatment of drug-resistant mesial temporal lobe epilepsy (mTLE) and were followed for more than 5 years. Indications for the procedure were the following: (1) verbally dominant-sided surgery in patients with a radiologically normal hippocampus or normal/near normal memory, and (2) surgery for patients with concomitant epileptic activity on the contralateral side, that is, when the surgery was considered a high risk for severe postoperative memory decline. Seizure outcome was evaluated using Engel's classification 1, 2, and 3 years after surgery, and at the last visit (LV). Three subgroups were evaluated as well: magnetic resonance imaging (MRI) negative (MN), hippocampal sclerosis (HS), and normal hippocampus with extrahippocampal lesion (NHEL). The long-term cognitive outcome was followed through to LV in patients who underwent verbally dominant-sided surgery. Hippocampal volume (HV), diffusion tensor parameters (DTP), and glucose utilization (GU) were determined from MRI and fluorodeoxyglucose-positron emission tomography (FDG-PET) studies performed before and >6 months after surgery. RESULTS Whereas the rate of Engel class I as a whole was 71% at 1 year and 67% at LV, the rates in the MN, HS, and NHEL groups were 60%, 67%, and 100% at 1 year, respectively, and 70%, 56%, and 80% at LV, respectively. Memory indices after verbally dominant-sided surgery transiently declined at 1 month but recovered to and remained at the preoperative level through LV. The HV, DTP of the fornix, and GU of the temporal lobe on the treated side showed pathologic changes even when the transiently declined memory indices had recovered to the preoperative level. SIGNIFICANCE The long-term outcome for complex partial seizures after MHT + MST/L was comparable to that seen after anterior temporal lobectomy. The long-term cognitive outcome was favorable, even for patients with a high risk of severe postoperative memory decline. MHT + MST/L may be a treatment option for mTLE in which resective surgery carries a risk of postoperative memory decline, particularly in patients without MRI lesion. A discrepancy between the preserved memory and the pathologic neuroradiologic changes indicates the necessity for further studies including functional MRI.
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Affiliation(s)
- Kenichi Usami
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Mayumi Kubota
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Kensuke Kawai
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Naoto Kunii
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Takeshi Matsuo
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Kenji Ibayashi
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Miwako Takahashi
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Kyousuke Kamada
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Toshimitsu Momose
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Shigeki Aoki
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Nobuhito Saito
- Department of Neurosurgery and Radiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
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22
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Krylov VV, Gusev EI, Guekht AB, Trifonov IS, Lebedeva AV, Kaimovsky IL. The history of surgical treatment of epilepsy in the Russian Federation. Zh Nevrol Psikhiatr Im S S Korsakova 2016. [DOI: 10.17116/jnevro2016116926-12] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
Multiple hippocampal transection (MHT) is a novel surgical procedure that serves to disrupt seizure propagation fibers within the hippocampus without impairing verbal memory or the loss of stem cells. Given the paucity of literature regarding the utility and long-term outcome of MHT, a review is presented of the current literature to support the utility of this procedure in the treatment of intractable temporal lobe epilepsy. Long-term outcome analysis of this technique has been reported by 2 independent groups. Both groups used intraoperative electrocorticography. All patients underwent multiple subpial transection on the neocortex and MHT on the hippocampus.
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Affiliation(s)
- Arun Angelo Patil
- Creighton University Medical Center, Division of Neurosurgery, 601 North 30th Street, Omaha, NE 68131, USA.
| | - Andrea Jennifer Chamczuk
- Creighton University Medical Center, Division of Neurosurgery, 601 North 30th Street, Omaha, NE 68131, USA
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Shimada S, Kunii N, Kawai K, Usami K, Matsuo T, Uno T, Koizumi T, Saito N. Spontaneous Temporal Pole Encephalocele Presenting with Epilepsy: Report of Two Cases. World Neurosurg 2015; 84:867.e1-6. [DOI: 10.1016/j.wneu.2015.04.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/15/2015] [Indexed: 11/27/2022]
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Minami N, Morino M, Uda T, Komori T, Nakata Y, Arai N, Kohmura E, Nakano I. Surgery for amygdala enlargement with mesial temporal lobe epilepsy: pathological findings and seizure outcome. J Neurol Neurosurg Psychiatry 2015; 86:887-94. [PMID: 25224675 DOI: 10.1136/jnnp-2014-308383] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 09/02/2014] [Indexed: 11/04/2022]
Abstract
OBJECTIVE Amygdala enlargement (AE) has been suggested to be a subtype of mesial temporal lobe epilepsy (MTLE). However, most reports related to AE have referred to imaging studies, and there have been few reports regarding surgical and pathological findings. The present study was performed to clarify the surgical outcomes and pathology of AE. METHODS Eighty patients with drug-resistant MTLE were treated surgically at the Tokyo Metropolitan Neurological Hospital between April 2010 and July 2013. Of these patients, 11 were diagnosed as AE based on presurgical MRI. Nine patients with AE underwent selective amygdalohippocampectomy, while the remaining two patients underwent selective amygdalotomy with hippocampal transection. Intraoperative EEG was routinely performed. The histopathology of the resected amygdala tissue was evaluated and compared with the amygdala tissue of patients with hippocampal sclerosis. RESULTS Pathological findings indicated that 10 of 11 specimens had closely clustering hypertrophic neurons with vacuolisation of the background matrix. Slight gliosis was seen in nine specimens, while the remaining two showed no gliotic changes. Intraoperative EEG showed abnormal sharp waves that seemed to originate not from the amygdala but from the hippocampus in all cases. Ten patients became seizure-free during the postoperative follow-up period. CONCLUSIONS Histopathologically, clustering hypertrophic neurons and vacuolation with slight gliosis or without gliosis were considered to be pathological characteristics of AE. Amygdalohippocampectomy or hippocampal transection with amygdalotomy is effective for seizure control in patients with AE.
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Affiliation(s)
- Noriaki Minami
- Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan Department of Neurosurgery, Kobe University School of Medicine, Kobe, Hyogo, Japan
| | - Michiharu Morino
- Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Takehiro Uda
- Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Takashi Komori
- Department of Laboratory Medicine and Pathology (Neuropathology), Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Yasuhiro Nakata
- Department of Neuroradiology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Nobutaka Arai
- Brain Pathology Research Center, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Eiji Kohmura
- Department of Neurosurgery, Kobe University School of Medicine, Kobe, Hyogo, Japan
| | - Imaharu Nakano
- Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
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Evaluation of Posterior Hippocampal Epileptogenicity During Epilepsy Surgery For Temporal Lobe Cavernoma by the Occipital Approach. World Neurosurg 2015; 84:1494.e1-6. [PMID: 25936905 DOI: 10.1016/j.wneu.2015.04.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/22/2015] [Accepted: 04/22/2015] [Indexed: 11/20/2022]
Abstract
BACKGROUND Cavernomas frequently are associated with intractable epilepsy. When cavernomas located in the temporal lobe are associated with intractable epilepsy, the hippocampus also may have an epileptic focus. The objective in the present study was to clarify the importance of evaluation of the posterior hippocampal epileptogenicity during epilepsy surgery for posteromedial temporal lobe cavernoma. CASE DESCRIPTIONS In this study, we describe 2 rare cases of medically intractable epilepsy in patients with posteromedial temporal lobe cavernomas who underwent surgery via the occipital approach. Using longitudinal insertion of depth electrodes into the hippocampus, we evaluated epileptogenicity in both patients from the cavernoma cavity and its surrounding hemosiderin, as well as from the posterior hippocampus near the cavernoma. We show that the transoccipital approach to the posteromedial temporal lobe is compatible with depth electrode insertion and subdural electrode placement on the temporal lobe, enabling an accurate evaluation of potential epileptogenic zones in the posterior part of the hippocampus. Both patients did not experience any seizures and had no postoperative neurologic deficits, and their cognitive functions were intact. CONCLUSIONS The transoccipital approach enables the optimization of the extent of posterior hippocampectomy while avoiding unnecessary resection for seizure control. We suggest resecting the posterior part of the hippocampus in addition to the cavernoma and surrounding areas in patients with medically refractory epilepsy due to a posteromedial temporal cavernoma. Tailored systematic resection guided by intraoperative electrocorticography and electroencephalography with a depth electrode was important and necessary in the present cases.
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Abstract
This article reviews the current status of surgical treatment of epilepsy and introduces the ongoing challenges. Seizure outcome of resective surgery for focal seizures associated with focal lesions is satisfactory. Particularly for mesial temporal lobe epilepsy, surgical treatment should be considered from the earlier stage of the disease. Meanwhile, surgical outcome in nonlesional extratemporal lobe epilepsy is still to be improved using various approaches. Disconnective surgeries reduce surgical complications of extensive resections while achieving equivalent or better seizure outcomes. Multiple subpial transection is still being modified expecting a better outcome by transection to the vertical cortices along the sulci- and multi-directional transection from a single entry point. Hippocampal transection is expected to preserve memory function while interrupting the abnormal epileptic synchronization. Proper selection or combination of subdural and depth electrodes and a wide-band analysis of electroencephalography may improve the accurate localization of epileptogenic region. Patients for whom curative resective surgery is not indicated because of generalized or bilateral multiple nature of their epilepsies, neuromodulation therapies are options of treatment which palliate their seizures.
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Affiliation(s)
- Kensuke Kawai
- Department of Neurosurgery and Epilepsy Center, NTT Medical Center Tokyo
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Vojtěch Z, Malíková H, Krámská L, Liščák R, Vladyka V. MRI-guided stereotactic amygdalohippocampectomy: a single center experience. Neuropsychiatr Dis Treat 2015; 11:359-74. [PMID: 25709460 PMCID: PMC4334329 DOI: 10.2147/ndt.s69350] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND This paper presents our experience of stereotactic radiofrequency amygdalohippocampectomy performed for intractable mesial temporal lobe epilepsy. METHODS The article describes the cases of 61 patients who were treated during the period from 2004 to 2010. Mean postoperative follow-up was 5.3 years. Neuropsychological results were obtained for a subset of 31 patients. RESULTS At their last postsurgical visit, 43 (70.5%) patients were Engel class I, six (9.8%) class II, nine (14.8%) class III, and three (4.9%) class IV. The surgery was complicated by four intracranial hematomas. One of them caused acute hydrocephalus and was treated by shunting and resolved without sequelae, while another caused transitory aphasia. The remaining hematomas were asymptomatic. There were two cases of meningitis which required antibiotic treatment. One patient committed suicide due to postoperative depression. After the procedure, we performed open epilepsy surgery and rethermolesions in three and two patients, respectively (8.2%). Patients showed increases in their mean full scale, verbal, and performance intelligence quotient (IQ) scores of 4, 3, and 4 IQ points, respectively (P<0.05). Five (17.2%), four (13.8%), and four (13.3%) patients improved their full scale, verbal, and performance IQ scores, respectively. No significant changes were found in memory performance, with a mean increase of 1, 3, and 0 memory quotient points in global, verbal, and visual memory, respectively (P<0.05). Global memory improved in three (10.3%) patients, verbal memory in one (3.4%), and one patient (3.3%) showed deterioration in visual memory. CONCLUSION Stereotactic radiofrequency amygdalohippocampectomy offers a safe, effective, and less aggressive treatment modality in cases of well-defined mesial temporal lobe epilepsy. Seizure outcome is comparable with the results of conventional epilepsy surgery and cognitive results could be even better.
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Affiliation(s)
- Zdeněk Vojtěch
- Department of Neurology, Na Homolce Hospital, Prague, Czech Republic
| | - Hana Malíková
- Department of Radiodiagnostics, Na Homolce Hospital, Prague, Czech Republic
| | - Lenka Krámská
- Department of Psychology, Na Homolce Hospital, Prague, Czech Republic
| | - Roman Liščák
- Department of Stereotactic and Radiation Neurosurgery, Na Homolce Hospital, Prague, Czech Republic
| | - Vilibald Vladyka
- Department of Stereotactic and Radiation Neurosurgery, Na Homolce Hospital, Prague, Czech Republic
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Isaeva E, Romanov A, Holmes GL, Isaev D. Status epilepticus results in region-specific alterations in seizure susceptibility along the hippocampal longitudinal axis. Epilepsy Res 2014; 110:166-70. [PMID: 25616469 DOI: 10.1016/j.eplepsyres.2014.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 11/23/2014] [Accepted: 12/08/2014] [Indexed: 11/19/2022]
Abstract
Temporal lobe epilepsy (TLE) is the most common epilepsy syndrome in adults. In particular, the hippocampus is highly susceptible to abnormal synchronization. Recent advances in the surgical treatment of patients with refractory TLE have shown that multiple hippocampal transections can effectively control seizures. It has been suggested that in TLE the synchrony in the longitudinal connections is required for seizure generation; however the physiological background for the increase in hippocampal synchronization along the longitudinal axis is not fully understood. The hippocampus varies in seizure susceptibility along its longitudinal axis with the ventral hippocampus (VH) region being more seizure-prone and susceptible to neuronal damage than the dorsal hippocampus (DH). In the present study we studied seizure susceptibility along the longitudinal axis of the hippocampus following pilocarpine-induced status epilepticus (SE). In control conditions the VH generates epileptiform activity (EA) more frequently than the DH when exposed to a low Mg(2+)/1Ca(2+)/5K(+) solution. Following SE the probability of inducing epileptiform activity (EA) is similar in the VH and DH slices. This SE-induced change is due to an increase in the proportion of DH slices responding to the low Mg(2+)/1Ca(2+)/5K(+) solution with EA. Moreover, both the VH and DH show similar responses to a low Mg(2+)/1Ca(2+)/5K(+) solution. These findings indicate that the hippocampus undergoes significant functional changes following SE, which may provide the necessary increase of synchrony along the longitudinal axis to generate seizures in TLE.
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Affiliation(s)
- Elena Isaeva
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, USA; Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine.
| | - Arthur Romanov
- Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Gregory L Holmes
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, USA
| | - Dmytro Isaev
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, USA; Department of Cellular Membranology, Bogomoletz Institute of Physiology, Kiev, Ukraine
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Kunii N, Kawai K, Kamada K, Ota T, Saito N. The significance of parahippocampal high gamma activity for memory preservation in surgical treatment of atypical temporal lobe epilepsy. Epilepsia 2014; 55:1594-601. [PMID: 25182809 DOI: 10.1111/epi.12764] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Resective surgery for mesial temporal lobe epilepsy (MTLE) with a correspondent lesion has been established as an effective and safe procedure. Surgery for temporal lobe epilepsies with bilateral hippocampal sclerosis or without correspondent lesions, however, carries a higher risk of devastating memory decline, underscoring the importance of establishing the memory-dominant side preoperatively and adopting the most appropriate procedure. In this study, we focused on high gamma activities (HGAs) in the parahippocampal gyri and investigated the relationship between memory-related HGAs and memory outcomes after hippocampal transection (HT), a hippocampal counterpart to neocortical multiple subpial transection. The transient nature of memory worsening after HT provided us with a rare opportunity to compare HGAs and clinical outcomes without risking permanent memory disorders. METHODS We recorded electrocorticography from parahippocampal gyri of 18 patients with temporal lobe epilepsy while they executed picture naming and recognition tasks. Memory-related HGA was quantified by calculating differences in power amplification of electrocorticography signals in a high gamma range (60-120 Hz) between the two tasks. We compared memory-related HGAs from correctly recognized and rejected trials (hit-HGA and reject-HGA). Using hit-HGA, we determined HGA-dominant sides and compared them with memory outcomes after HT performed on seven patients. RESULTS We observed memory-related HGA mainly between 500 and 600 msec poststimulus. Hit-HGA was significantly higher than reject-HGA. Three patients who had surgery on the HGA-dominant side experienced transient memory worsening postoperatively. The postoperative memory functions of the other four patients remained unchanged. SIGNIFICANCE Parahippocampal HGA was indicated to reflect different memory processes and be compatible with the outcomes of HT, suggesting that HGA could provide predictive information on whether the mesial temporal lobe can be resected without causing memory worsening. This preliminary study suggests a refined surgical strategy for atypical MTLE based on reliable memory lateralization.
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Affiliation(s)
- Naoto Kunii
- Department of Neurosurgery, The University of Tokyo, Tokyo, Japan
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Sánchez JJG, Rincon-Torroella J, Prats-Galino A, Notaris MD, Berenguer J, Rodríguez EF, Benet A. New endoscopic route to the temporal horn of the lateral ventricle: surgical simulation and morphometric assessment. J Neurosurg 2014; 121:751-9. [DOI: 10.3171/2014.5.jns132309] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
The temporal horn of the lateral ventricle is a complex structure affected by specific pathological conditions. Current approaches to the temporal horn involve a certain amount of corticotomy and white matter disruption. Surgeons therefore set aside anterior temporal lobectomy as a last resource and avoid it in the dominant hemisphere. The authors propose a minimally invasive endoscopic intraventricular approach to the temporal horn and describe a standardized analysis and technical assessment of the feasibility of this approach.
Methods
To determine the best trajectory, angulation, and entry point to the temporal horn of the lateral ventricle, the authors evaluated 50 cranial MRI studies (100 temporal lobes) from healthy patients. They studied and systematized the neurosurgical endoscopic anatomy. They also simulated the proposed approach in 9 cadaveric specimens (18 approaches).
Results
Mean scalp entry point coordinates (± SD) were 2.7 ± 0.28 cm lateral to the inion and 5.6 ± 0.41 cm superior to the inion. The mean total distance from the uncal recess to the scalp (± SD) was 10.64 ± 0.6 cm. The mean total intraparenchymal distance crossed by the endoscope was 3.76 ± 0.36 cm. The approach was successfully completed in all studied specimens.
Conclusions
In this study, the endoscopic intraventricular approach to the temporal horn is standardized. The morphometric analysis makes this approach anatomically feasible and replicable. This approach provides minimally invasive endoscopic access to the uncal recess, amygdala, hippocampus, fornix, and paraventricular temporal lobe structures. The following essential strategies enabled access to and maneuverability inside the temporal horn: tailored preoperative planning of the trajectory and use of anatomical and radiological references, constant irrigation, and an angled endoscopic lens. Safety assessment and novel instruments and techniques may be proposed to advance this very promising route to pathological changes in the temporal lobe.
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Affiliation(s)
- Jose Juan González Sánchez
- 1Departments of Neurosurgery and
- 3Department of Neurosurgery, Skull Base and Cerebrovascular Laboratory, University of California, San Francisco, California
| | | | - Alberto Prats-Galino
- 5Laboratory of Surgical Neuroanatomy, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain
| | - Matteo de Notaris
- 5Laboratory of Surgical Neuroanatomy, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain
| | - Joan Berenguer
- 2Radiology, Hospital Clinic i Provincial de Barcelona, Barcelona, Spain
| | | | - Arnau Benet
- 3Department of Neurosurgery, Skull Base and Cerebrovascular Laboratory, University of California, San Francisco, California
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Schramm J. Epilepsy Surgery and the Evolution of Clinical and Translational Science. Neurosurgery 2014; 61 Suppl 1:54-65. [DOI: 10.1227/neu.0000000000000399] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Johannes Schramm
- Professor emeritus, Medical Faculty, Bonn University, Bonn, Germany
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Landazuri P, Miller J, Lüders H. A case report of a Wada test after dominant hemisphere multiple hippocampal transections: Pathophysiology of confusion after amobarbital injection. EPILEPSY & BEHAVIOR CASE REPORTS 2014; 2:130-2. [PMID: 25667890 PMCID: PMC4307959 DOI: 10.1016/j.ebcr.2014.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 05/16/2014] [Indexed: 11/28/2022]
Abstract
Dialepsis is defined as a predominant alteration of consciousness with preservation of motor tone and the ability to perform movements. While dialepsis is a common feature of both focal and generalized epilepsies, its precise symptomatogenic zone and pathogenesis remain undefined. This case report describes a patient who underwent intracarotid amobarbital procedures before and after dominant hemisphere multiple hippocampal transections. From our observations, we propose a possible pathogenesis for the generation of dialeptic seizures.
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Affiliation(s)
- Patrick Landazuri
- University Hospitals, Case Medical Center, Department of Neurology, Epilepsy Division, 11100 Euclid Avenue, Lakeside 3200, Cleveland, OH, USA
- University of Kansas Medical Center, Department of Neurology, 3599 Rainbow Blvd, Kansas City, KS 66103, USA
- Corresponding author at: 3599 Rainbow Blvd, Kansas City, KS 66103, USA. Tel.: + 1 913 588 6970.
| | - Jonathan Miller
- University Hospitals, Case Medical Center, Department of Neurosurgery, 11100 Euclid Avenue, Lakeside 3200, Cleveland, OH 44106, USA
| | - Hans Lüders
- University Hospitals, Case Medical Center, Department of Neurology, Epilepsy Division, 11100 Euclid Avenue, Lakeside 3200, Cleveland, OH, USA
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Long term follow-up after multiple hippocampal transection (MHT). Seizure 2013; 22:731-4. [DOI: 10.1016/j.seizure.2013.05.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/17/2013] [Accepted: 05/22/2013] [Indexed: 12/14/2022] Open
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Uda T, Morino M, Ito H, Minami N, Hosono A, Nagai T, Matsumoto T. Transsylvian hippocampal transection for mesial temporal lobe epilepsy: surgical indications, procedure, and postoperative seizure and memory outcomes. J Neurosurg 2013; 119:1098-104. [DOI: 10.3171/2013.6.jns13244] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Amygdalohippocampectomy is a well-established, standard surgery for medically intractable mesial temporal lobe epilepsy (MTLE). However, in the case of MTLE without hippocampal atrophy or sclerosis, amygdalohippocampectomy is associated with decreased postoperative memory function. Hippocampal transection (HT) has been developed to overcome this problem. In HT the hippocampus is not removed; rather, the longitudinal hippocampal circuits of epileptic activities are disrupted by transection of the pyramidal layer of the hippocampus. The present study describes a less invasive modification of HT (transsylvian HT) and presents the seizure and memory outcomes for this procedure.
Methods
Thirty-seven patients with MTLE (18 men and 19 women; age range 9–63 years; 19 with surgery on the right side and 18 with surgery on the left side; seizure onset from 3 to 34 years) who were treated with transsylvian HT were retrospectively analyzed. All patients had left-side language dominance, and follow-up periods ranged from 12 to 94 months (median 49 months). Seizure outcomes were evaluated for all patients by using the Engel classification. Memory function was evaluated for 22 patients based on 3 indices (verbal memory, nonverbal memory, and delayed recall), with those scores obtained using the Wechsler Memory Scale–Revised. Patients underwent evaluation of the memory function before and after surgery (6 months–1 year).
Results
Engel Class I (completely seizure free) was achieved in 25 patients (67.6%). Class II and Class III designation was achieved in 10 (27%) and 2 patients (5.4%), respectively. There were differences in memory outcome between the sides of operation. On the right side, verbal memory significantly increased postoperatively (p = 0.003) but nonverbal memory and delayed recall showed no significant change after the operation (p = 0.718 and p = 0.210, respectively). On the left side, all 3 indices (verbal memory, nonverbal memory, and delayed recall) showed no significant change (p = 0.331, p = 0.458, and p = 0.366, respectively).
Conclusions
Favorable seizure outcome and preservation of verbal memory were achieved with transsylvian HT for the treatment of MTLE without hippocampal atrophy or sclerosis.
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Stereotactic radiofrequency amygdalohippocampectomy: Two years of good neuropsychological outcomes. Epilepsy Res 2013; 106:423-32. [DOI: 10.1016/j.eplepsyres.2013.07.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 06/18/2013] [Accepted: 07/26/2013] [Indexed: 10/26/2022]
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Takahashi M, Soma T, Kawai K, Koyama K, Ohtomo K, Momose T. Voxel-based comparison of preoperative FDG-PET between mesial temporal lobe epilepsy patients with and without postoperative seizure-free outcomes. Ann Nucl Med 2012; 26:698-706. [DOI: 10.1007/s12149-012-0629-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 06/24/2012] [Indexed: 11/30/2022]
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Surgical techniques for the treatment of temporal lobe epilepsy. EPILEPSY RESEARCH AND TREATMENT 2012; 2012:374848. [PMID: 22957228 PMCID: PMC3420380 DOI: 10.1155/2012/374848] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 12/07/2011] [Accepted: 12/26/2011] [Indexed: 11/17/2022]
Abstract
Temporal lobe epilepsy (TLE) is the most common form of medically intractable epilepsy. Advances in electrophysiology and neuroimaging have led to a more precise localization of the epileptogenic zone within the temporal lobe. Resective surgery is the most effective treatment for TLE. Despite the variability in surgical techniques and in the extent of resection, the overall outcomes of different TLE surgeries are similar. Here, we review different surgical interventions for the management of TLE.
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Umeoka SC, Lüders HO, Turnbull JP, Koubeissi MZ, Maciunas RJ. Requirement of longitudinal synchrony of epileptiform discharges in the hippocampus for seizure generation: a pilot study. J Neurosurg 2011; 116:513-24. [PMID: 22175726 DOI: 10.3171/2011.10.jns11261] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The goal in this study was to assess the role of longitudinal hippocampal circuits in the generation of interictal and ictal activity in temporal lobe epilepsy (TLE) and to evaluate the effects of multiple hippocampal transections (MHT). METHODS In 6 patients with TLE, the authors evaluated the synchrony of hippocampal interictal and ictal epileptiform discharges by using a cross-correlation analysis, and the effect of MHT on hippocampal interictal spikes was studied. Five of the 6 patients were studied with depth electrodes, and epilepsy surgery was performed in 4 patients (anterior temporal lobectomy in 1 and MHT in 3). RESULTS Four hundred eighty-two (95.1%) of 507 hippocampal spikes showed an anterior-to-posterior propagation within the hippocampus, with a fixed peak-to-peak interval. During seizures, a significant increase of synchronization between different hippocampal regions and between the hippocampus and the ipsilateral anterior parahippocampal gyrus was observed in all seizures. An ictal increase in synchronization between the hippocampus and ipsilateral amygdala was seen in only 24.1% of the seizures. No changes in synchronization were noticed during seizures between the hippocampi and the amygdala on either side. The structure leading the epileptic seizures varied over time during a given seizure and also from one seizure to another. Spike analysis during MHT demonstrated that there were two spike populations that reacted differently to this procedure--namely, 1) spikes that showed maximum amplitude at the head of the hippocampus (type H); and 2) spikes that showed the highest amplitude at the hippocampal body (type B). A striking decrease in amplitude and frequency of type B spikes was noticed in all 3 patients after transections at the head or anterior portion of the hippocampal body. Type H spikes were seen in 2 cases and did not change in amplitude and frequency throughout MHT. Type B spikes showed constantly high cross-correlation values in different derivations and a relatively fixed peak-to-peak interval before MHT. This fixed interpeak delay disappeared after the first transection, although high cross-correlation values persisted unchanged. All patients who underwent MHT remained seizure free for more than 2 years. CONCLUSIONS These data suggest that synchronized discharges involving the complete anterior-posterior axis of the hippocampal/parahippocampal (H/P) formation underlie the spread of epileptiform discharges outside the H/P structures and, therefore, for the generation of epileptic seizures originating in the H/P structures. This conclusion is supported by the following observations. 1) Hippocampal spikes are consistently synchronized in the whole hippocampal structures, with a fixed delay between the different hippocampal areas. 2) One or two transections between the head and body of the hippocampal formation are sufficient to abolish hippocampal spikes that are synchronized along the anterior-posterior axis of the hippocampus. 3) Treatment with MHT leads to seizure freedom in patients with H/P epilepsy.
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Affiliation(s)
- Shuichi C Umeoka
- Epilepsy Center, University Hospitals Neurological Institute, Case Medical Center, 11100 Euclid Avenue, Cleveland, Ohio 44106-5040, USA
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Patil AA, Andrews RV. Nonresective hippocampal surgery for epilepsy. World Neurosurg 2011; 74:645-9. [PMID: 21492634 DOI: 10.1016/j.wneu.2010.06.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 06/15/2010] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Clinical experience with a new surgical procedure called multiple hippocampal transections is described. In this procedure, seizure circuits within the hippocampus are disrupted by making multiple cuts parallel to the hippocampal digitations; while the vertical functional fibers are preserved. METHODS Ten patients with temporal lobe epilepsy are described. The male/female ratio is 6:4, the ages of the patients were 20-53 years, and follow-up periods were 10-34 months, with a median of 21 months. Five patients had no hippocampal sclerosis, two had minimal sclerosis, and three had significant sclerosis. Six patients had surgery on the dominant side and five had failed the Wada test. Multiple hippocampal transections were made at 4-mm intervals. The neocortex was then treated with multiple subpial transections. In addition, six patients had resections of the temporal tip. RESULTS There were no permanent neurologic complications: seven patients are seizure-free, two have rare seizures, and one has 60% decrease in seizure frequency. Eight patients had both pre- and postoperative memory testing. Among these eight patients, five had improved verbal memory, three had improved visual memory, and three had a slight drop in visual memory. CONCLUSION This is a small series with a short follow-up period. However, the results are encouraging enough to warrant further trials. In addition, this may be an effective alternative procedure for those who fail the Wada test and do not have significant temporal lobe sclerosis or who have seizures originating from the dominant side.
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Kibler AB, Durand DM. Orthogonal wave propagation of epileptiform activity in the planar mouse hippocampus in vitro. Epilepsia 2011; 52:1590-600. [PMID: 21668440 DOI: 10.1111/j.1528-1167.2011.03125.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE In vitro brain preparations have been used extensively to study the generation and propagation of epileptiform activity. Transverse and longitudinal slices of the rodent hippocampus have revealed various patterns of propagation. Yet intact connections between the transverse and longitudinal pathways should generate orthogonal (both transverse and longitudinal) propagation of seizures involving the entire hippocampus. This study utilizes the planar unfolded mouse hippocampus preparation to reveal simultaneous orthogonal epileptiform propagation and to test a method of arresting propagation. METHODS This study utilized an unfolded mouse hippocampus preparation. It was chosen due to its preservation of longitudinal neuronal processes, which are thought to play an important role in epileptiform hyperexcitability. 4-Aminopyridine (4-AP), microelectrodes, and voltage-sensitive dye imaging were employed to investigate tissue excitability. KEY FINDINGS In 50-μm 4-AP, stimulation of the stratum radiatum induced transverse activation of CA3 cells but also induced a longitudinal wave of activity propagating along the CA3 region at a speed of 0.09 m/s. Without stimulation, a wave originated at the temporal CA3 and propagated in a temporal-septal direction could be suppressed with glutamatergic receptor antagonists. Orthogonal propagation traveled longitudinally along the CA3 pathway, secondarily invading the CA1 region at a velocity of 0.22 ± 0.024 m/s. Moreover, a local lesion restricted to the CA3 region could arrest wave propagation. SIGNIFICANCE These results reveal a complex two-dimensional epileptiform wave propagation pattern in the hippocampus that is generated by a combination of synaptic transmission and axonal propagation in the CA3 recurrent network. Epileptiform propagation block via a transverse selective CA3 lesion suggests a potential surgical technique for the treatment of temporal lobe epilepsy.
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Affiliation(s)
- Andrew B Kibler
- Neural Engineering Center, Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Sunaga S, Morino M, Kusakabe T, Sugano H, Shimizu H. Efficacy of hippocampal transection for left temporal lobe epilepsy without hippocampal atrophy. Epilepsy Behav 2011; 21:94-9. [PMID: 21497556 DOI: 10.1016/j.yebeh.2011.02.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Revised: 02/18/2011] [Accepted: 02/24/2011] [Indexed: 11/30/2022]
Abstract
We describe a case of left temporal lobe epilepsy without hippocampal atrophy. A 31-year-old woman presented with typical symptoms of complex partial seizures. Magnetic resonance imaging demonstrated slightly obscure internal structures in the left hippocampus. Scalp electroencephalography revealed interictal epileptiform discharges in the left temporal lobe. A Wada test with propofol determined the language-dominant hemisphere to be the left. Intraoperative electrocorticography revealed active epileptic discharges in the hippocampus and the anterior temporal basal area. The hippocampal epileptic area was treated with multiple transection, which led to the complete cessation of epileptic discharges. After surgery, the Rey Auditory Verbal Learning Test score decreased from 12 to 9. However, it returned to the preoperative level 6months after surgery. We describe this case as a typical example demonstrating the efficacy of hippocampal transection for seizure control and the preservation of verbal memory.
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Affiliation(s)
- Shigeki Sunaga
- Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital, Fuchu, Tokyo, Japan.
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Pallud J, Häussler U, Langlois M, Hamelin S, Devaux B, Deransart C, Depaulis A. Dentate gyrus and hilus transection blocks seizure propagation and granule cell dispersion in a mouse model for mesial temporal lobe epilepsy. Hippocampus 2011; 21:334-43. [DOI: 10.1002/hipo.20795] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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KOIZUMI S, KAWAI K, ASANO S, UEKI K, SUZUKI I, SAITO N. Familial Lateral Temporal Lobe Epilepsy Confirmed With Intracranial Electroencephalography and Successfully Treated by Surgery -Five Case Reports in One Family-. Neurol Med Chir (Tokyo) 2011; 51:604-10. [DOI: 10.2176/nmc.51.604] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Satoshi KOIZUMI
- Department of Neurosurgery, Graduate School of Medicine, the University of Tokyo
| | - Kensuke KAWAI
- Department of Neurosurgery, Graduate School of Medicine, the University of Tokyo
| | - Shuichiro ASANO
- Department of Neurosurgery, Graduate School of Medicine, the University of Tokyo
| | - Keisuke UEKI
- Department of Neurosurgery, Graduate School of Medicine, the University of Tokyo
| | - Ichiro SUZUKI
- Department of Neurosurgery, Graduate School of Medicine, the University of Tokyo
| | - Nobuhito SAITO
- Department of Neurosurgery, Graduate School of Medicine, the University of Tokyo
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Inferring spatiotemporal network patterns from intracranial EEG data. Clin Neurophysiol 2010; 121:823-35. [PMID: 20434948 DOI: 10.1016/j.clinph.2009.12.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2009] [Revised: 12/01/2009] [Accepted: 12/31/2009] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The characterization of spatial network dynamics is desirable for a better understanding of seizure physiology. The goal of this work is to develop a computational method for identifying transient spatial patterns from intracranial electroencephalographic (iEEG) data. METHODS Starting with bivariate synchrony measures, such as phase correlation, a two-step clustering procedure is used to identify statistically significant spatial network patterns, whose temporal evolution can be inferred. We refer to this as the composite synchrony profile (CSP) method. RESULTS The CSP method was verified with simulated data and evaluated using ictal and interictal recordings from three patients with intractable epilepsy. Application of the CSP method to these clinical iEEG datasets revealed a set of distinct CSPs with topographies consistent with medial temporal/limbic and superior parietal/medial frontal networks thought to be involved in the seizure generation process. CONCLUSIONS By combining relatively straightforward multivariate signal processing techniques, such as phase synchrony, with clustering and statistical hypothesis testing, the methods we describe may prove useful for network definition and identification. SIGNIFICANCE The network patterns we observe using the CSP method cannot be inferred from direct visual inspection of the raw time series data, nor are they apparent in voltage-based topographic map sequences.
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Morino M, Ichinose T, Uda T, Kondo K, Ohfuji S, Ohata K. Memory outcome following transsylvian selective amygdalohippocampectomy in 62 patients with hippocampal sclerosis. J Neurosurg 2009; 110:1164-9. [PMID: 19119880 DOI: 10.3171/2008.9.jns08247] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT It remains unclear whether selective amygdalohippocampectomy, an operative technique developed for use in epilepsy surgery to spare unaffected brain tissue and thus minimize the cognitive consequences of temporal lobe surgery, actually leads to a better memory outcome. The present study was performed to determine the effects of selective surgery on memory outcome in patients with intractable mesial temporal lobe epilepsy due to hippocampal sclerosis treated using transsylvian selective amygdalohippocampectomy (TSA). METHODS The study population consisted of 62 patients with left hemisphere language dominance who underwent left-(31 patients) or right-sided (31 patients) TSA. All patients underwent comprehensive neuropsychological testing before and 1 month and 1 year after unilateral TSA. Verbal Memory I, Nonverbal Memory I, Total Memory, Attention, and Delayed Recall were assessed using the Wechsler Memory Scale-Revised, whereas Verbal Memory II was assessed using the Miyake Verbal Retention Test (MVRT), and Nonverbal Memory II was assessed using the Benton Visual Retention Test. Separate repeated-measures multivariate analysis of variance (MANOVA) were performed for these intervals with memory scores. RESULTS The results of MANOVA indicated that patients who underwent right-sided TSA showed significant improvements in Verbal Memory I (preoperatively vs 1 month postoperatively, p < 0.0001; and preoperatively vs 1 year postoperatively, p = 0.0002), Nonverbal Memory I (preoperatively vs 1 month postoperatively, p = 0.0003; and preoperatively vs 1 year postoperatively, p = 0.006), and Delayed Recall (preoperatively vs 1 month postoperatively, p = 0.028) at both 1-month and 1-year follow-ups. In addition, Verbal Memory II (MVRT) was also significantly improved 1 year after surgery (p = 0.001). In the group of patients who underwent left-sided TSA, both Verbal Memory I and II were maintained at the same level 1 month after surgery, whereas the Verbal Memory I score 1 year after surgery increased with marginal significance (p = 0.074). In addition, Verbal Memory II showed significant improvement 1 year after surgery (p = 0.049). There were no significant changes in Nonverbal Memory I and II, Attention, or Delayed Recall at either the 1-month or 1-year follow-up. CONCLUSIONS Results of the present study indicated that left-sided TSA for hippocampal sclerosis tends to improve verbal memory function with the preservation of other types of memory function. Moreover, right-sided TSA for hippocampal sclerosis can lead to significant improvement in memory function, with memory improvement observed 1 month after right-sided TSA and persisting 1 year after surgery.
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Affiliation(s)
- Michiharu Morino
- Departments of Neurosurgery, Osaka City University Graduate School of Medicine, Osaka, Japan.
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Abstract
The idea of surgical treatment for epilepsy is not new. However, widespread use and general acceptance of this treatment has only been achieved during the past three decades. A crucial step in this direction was the development of video electroencephalographic monitoring. Improvements in imaging resulted in an increased ability for preoperative identification of intracerebral and potentially epileptogenic lesions. High resolution magnetic resonance imaging plays a major role in structural and functional imaging; other functional imaging techniques (e.g., positron emission tomography and single-photon emission computed tomography) provide complementary data and, together with corresponding electroencephalographic findings, result in a hypothesis of the epileptogenic lesion, epileptogenic zone, and the functional deficit zone. The development of microneurosurgical techniques was a prerequisite for the general acceptance of elective intracranial surgery. New less invasive and safer resection techniques have been developed, and new palliative and augmentative techniques have been introduced. Today, epilepsy surgery is more effective and conveys a better seizure control rate. It has become safer and less invasive, with lower morbidity and mortality rates. This article summarizes the various developments of the past three decades and describes the present tools for presurgical evaluation and surgical strategy, as well as ideas and future perspectives for epilepsy surgery.
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Affiliation(s)
- Johannes Schramm
- Department of Neurosurgery, University of Bonn Medical Center, Bonn, Germany
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Wang F, Sun T, Li XG, Liu NJ. Diffusion tensor tractography of the temporal stem on the inferior limiting sulcus. J Neurosurg 2008; 108:775-81. [PMID: 18377258 DOI: 10.3171/jns/2008/108/4/0775] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The aim of this study was to use diffusion tensor tractography (DTT) to define the 3D relationships of the uncinate fasciculus, anterior commissure, inferior occipitofrontal fasciculus, inferior thalamic peduncle, and optic radiation and to determine the positioning landmarks of these white matter tracts. METHODS The anatomy was studied in 10 adult human brain specimens. Brain DTT was performed in 10 healthy volunteers. Diffusion tensor tractography images of the white matter tracts in the temporal stem were obtained using the simple single region of interest (ROI) and multi-ROIs based on the anatomical knowledge. RESULTS The posteroinferior insular point is the anterior extremity of intersection of the Heschl gyrus and the inferior limiting sulcus. On the inferior limiting sulcus, this point is the posterior limit of the optic radiation, and the temporal stem begins at the limen insulae and ends at the posteroinferior insular point. The distance from the limen insulae to the tip of the temporal horn is just one third the length of the temporal stem. The uncinate fasciculus comprises the core of the anterior temporal stem, behind which the anterior commissure and the inferior thalamic peduncle are located, and they occupy the anterior third of the temporal stem. The inferior occipitofrontal fasciculus passes through the entire temporal stem. The most anterior extent of the Meyer loop is located between the anterior tip of the temporal horn and the limen insulae. Most of the optic radiation crosses the postmedian two thirds of the temporal stem. CONCLUSIONS On the inferior limiting sulcus, the posteroinferior insular point is a reliable landmark of the posterior limit of the optic radiations. The limen insulae, anterior tip of the temporal horn, and posteroinferior insular point may be used to localize the white matter fibers of the temporal stem in analyzing magnetic resonance imaging or during surgery.
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Affiliation(s)
- Feng Wang
- Department of Neurosurgery, Qilu Hospital of the Shandong University, Jinan, Shandong, China
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