dos Santos et al. Neurosurg Cases Rev 2018, 1:006 Volume 1 | Issue 1 Open Access Neurosurgery - Cases and Reviews ORIGINAL ARTICLE Surgical Treatment of Mesial Temporal Lobe Epilepsy: Selective Amygdalohippocampectomy Using Niemeyer’s Approach Adriana Rodrigues Libório dos Santos1*, Gabriel Mufarrej1, Priscila Oliveira da Conceição2, Paulo Luiz da Costa Cruz1, Daniel Dutra Cavalcanti1, Leila Chimelli3 and Paulo Niemeyer Filho1 1Department of Neurosurgery, State Brain Institute Paulo Niemeyer, Rio de Janeiro, Brazil 2Department of Neurology, State Brain Institute Paulo Niemeyer, Rio de Janeiro, Brazil Check for 3Department of Neuropathology, State Brain Institute Paulo Niemeyer, Rio de Janeiro, Brazil updates *Corresponding author: Adriana Rodrigues Libório dos Santos, MD, Institution: State Brain Institute Paulo Niemeyer/ Instituto Estadual do Cérebro Paulo Niemeyer (IECPN), Neurosurgery Department, Rio de Janeiro, Brazil to treat pathology. Seizure is derived from the Greek Abstract and seize means “capture” or “take ownership”. Epi- Objective: Selective Amygdalohippocampectomy (SAH) is lepsy encompasses several types of disorders with dif- a widespread technique for Mesial Temporal Lobe Epilepsy (MTLE) treatment. Dr. Niemeyer was the first to describe ferent symptoms, and clinical manifestations [1-3]. The SAH using transventricular approach technique in 1958. In International League Against Epilepsy (ILAE) defines ep- 2018, we celebrate 60 years of the original description of ilepsy as “two or more recurrent seizures over a period Niemeyer’s approach. This study reviews the approach in greater than 24 hours, without a clear set cause”. The light of currently technology and shows the results achieved with patients submitted to SAH following Niemeyer’s ap- Term Temporal Lobe Epilepsy (TLE) was introduced in proach at Instituto Estadual do Cérebro Paulo Niemeyer the ILAE classification in 1989 as the group of “Symp- (IECPN)*. tomatic epilepsies related to localization characterized Methods: A retrospective case series of MTLE patients by seizures with specific mode of precipitation”. Over who underwent SAH using the transventricular approach the years, there were changes in the classification and between August 2013 and October 2015 at IECPN. Only in 2017 the newest revision of terms and concepts of cases with Hippocampal Sclerosis (HS) were included. epilepsies was published [1-5]. Results: We identified 13 HS patients with 37.4 years mean age who underwent SAH, with favorable outcomes, The temporal lobe is the most epileptogenic region 11 (84.6%) classified as Engel I while the other 2 (15.4%) of the human brain and the most common site of the as Engel II. epileptic syndrome called Mesial Temporal Lobe Epilep- Conclusion: In our sample, the pioneer transventricular sy (MTLE) [1,3,5-9]. MTLE has its peculiarities. Research approach described by Niemeyer was followed to perform of the Montreal Neurological Institute (MNI) suggested SAH while using current surgical resources with excellent outcomes. a psychic phenomenon with experimental hallucina- tions during intraoperative stimulation of this region. Keywords Gibbs and Lennox suggested the term “psychomotor Epilepsy, Temporal lobe, Amygdala, Hippocampus, Selec- epilepsy” to set a pattern of emotional mental and auto- tive amygdalohippocampectomy mations disorders, for crisis originated in the temporal lobe [1,10]. Gastaut proposed the term “Complex Par- Introduction tial Seizures” (CPS) for partial seizures associated with Epilepsy is a broadly studied disease, it affects about consciousness loss [1,10]. ILAE changed the term re- 1% of the world population, and is a common, difficult cently to “Focal Impaired Awareness Seizure” (FIAS) [5]. Citation: dos Santos ARL, Mufarrej G, da Conceição PO, Cruz PLC, Cavalcanti DD, et al. (2018) Surgical Treatment of Mesial Temporal Lobe Epilepsy: Selective Amygdalohippocampectomy Using Niemey- er’s Approach. Neurosurg Cases Rev 1:006. Accepted: November 17, 2018; Published: November 19, 2018 Copyright: © 2018 dos Santos ARL, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. dos Santos et al. Neurosurg Cases Rev 2018, 1:006 • Page 1 of 8 • EEG and video-EEG (VEEG) tests are indispensable larly in the H2 and H3 areas of the hippocampus” (i.e., to research and determine the epileptogenic zone CA2 and CA3) in surgical specimens. This made it possi- [4,11,12]. In about thirty percent of patients with MTLE, ble to affirm the secondary role of the temporal cortex. surface EEG detection of epileptogenic zone of dis- Based on these results, Niemeyer idealized a surgical charge, with or without bilateral focus lateralization may technique where the amygdala and the hippocampus be flawed. In these cases, we can use the Stereoelectro- could be selectively resected, preserving the temporal encephalography (S-EEG), which uses depth electrodes cortex, which then became the Selective Amygdalohip- introduced by bilateral foramen ovale, to the mesial pocampectomy (SAH) [21-24]. temporal lobe region to record the FIAS [5,13,14]. In 1958, Paulo Niemeyer published the paper “The With the Magnetic Resonance Imaging (MRI), there Transventricular Amygdalo-Hippocampectomy in Tem- has been dramatic improvement in the diagnosis of poral Lobe Epilepsy”. This technique was spread around brain disorders, including cases of epilepsy. The prima- the world and continues to be used today. Microsurgi- ry objective of the image in patients with seizure is to cal anatomy of the temporal lobe in the human brain is exclude a possible structural lesion as a cause, either a complex, with great surgical importance. But it requires brain tumor or an arteriovenous malformation. MRI is the neurosurgeon to have the proper knowledge of recommended for all patients who have FIAS. The Hip- treatment for the diseases that affect the region [21,23- pocampal Sclerosis (HS) is the most common pathologi- 26]. MTLE represents about two thirds of the popula- cal substrate found in MTLE patients MRI [4,12,15]. tion undergoing surgical treatment with seizures refrac- Antiepileptic Drugs (AEDs) such as phenytoin, carba- tory to treatment [1,25]. mazepine, valproate, phenobarbital is widely used in FIAS SAH is a widespread surgical technique used in cases treatment. As well as newer drugs such as topiramate, of refractory psychomotor seizures [22]. In 1973, Wies- lamotrigine, oxcarbazepine and pregabalin [16]. Patients er and Yasargil introduced the transsylvian approach for who remain refractory to drug therapy, should be evaluat- the mesial temporal lobe structures resection [2,22]. ed for possible surgical epilepsy treatment [16-20]. In 2018, we celebrate 60 years of the original de- Between the 1940s and 1950s, neurosurgeons, neu- scription of Niemeyer’s approach. It also encouraged rologists and neurophysiologists furthered studies to several neurosurgeons to apply other access routes to elucidate temporal lobe epilepsy, also using the Electro- the SAH. At the Epilepsy Center at the IECPN, the stan- encephalogram (EEG) to locate the correct epileptic fo- dard transventricular approach is usually performed. cus. After confirming the epileptic focus in the temporal lobe for psychomotor seizures, Paulo Niemeyer with the Methods help of neurologists, used the EEG to study the epilepto- This paper is a retrospective study and data analysis genic activity of the hippocampus and its relation with of results of patients undergoing SAH by transventricu- cortical activity. Niemeyer believed that psychomotor lar approach at IECPN between August 2013 and Octo- epilepsy had its origin in the amygdala, the temporoin- ber 2015. sular cortex, or the hippocampus, and these structures together formed a “functional unit responsible for the MTLE diagnosed patients, refractory to AEDs treat- production of psychomotor attacks, leaving most cases ment, VEEG consistent results visualized on MRI, diag- of the temporal cortex in the background”. Based on his nosed as HS and undergoing SAH, were included in this studies, Niemeyer showed “astrocytic gliosis, particu- study. While those, with tumor or other cause induced Figure 1: Surgical position: Supine position with a pad under the ipsilateral shoulder, head lateralized to 45 degree and de- flected. dos Santos et al. Neurosurg Cases Rev 2018, 1:006 • Page 2 of 8 • MTLE, or who underwent nonselective amygdalohippo- amygdala with the optic tract and basal ganglia were campectomy, were not. the aspiration limits. Then the fimbriae and the hippo- campus were dissected to expose the arachnoid, which All patients underwent MRI scans to show HS signals. limits the hippocampus and the cistern Ambiens. T2 and STIR sequences in coronal were used to study the mesial temporal region. The fimbriae and hippocampus were then dissected, and with arachnoid exposure, which limits the hippo- After general anesthesia, patients were placed in the campus and the Ambiens cistern. En bloc resection of surgical supine position, with the head lateralized and the hippocampus, about 2.5 to 3.0 cm as well as resec- deflected. This deflection is extremely important to ex- tion of the parahippocampal gyrus are performed (Fig- pose the mesial structures (Figure 1). A Temporal crani- ure 2A, Figure 2B, Figure 2C and Figure 2D). otomy was performed. Follow up of patients undergoing SAH is made by The