Original Article. Takehiro Uda 1,2, Noritsugu Kunihiro 2, Kosuke Nakajo 1, Ichiro Kuki 3, Masataka Fukuoka 3, Kenji Ohata 1.

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1 SNI: Epilepsy OPEN ACCESS For entire Editoril Bord visit : Editor: Trvis Sen Tierney, MD Nicklus Children's Hospitl; Mimi, FL, USA Originl Article Seizure freedom from temporl loe epilepsy with mesil temporl loe tumor y tumor removl lone without hippocmpectomy despite remining norml dischrges on intropertive electrocorticogrphy: Report of two peditric cses nd reconsidertion of the surgicl strtegy Tkehiro Ud 1,2, Noritsugu Kunihiro 2, Kosuke Nkjo 1, Ichiro Kuki 3, Mstk Fukuok 3, Kenji Oht 1 1 Deprtment of Neurosurgery, Osk City University Grdute School of Medicine, Deprtments of 2 Peditric Neurosurgery nd 3 Peditric Neurology, Osk City Generl Hospitl, Osk, Jpn E mil: *Tkehiro Ud ud_tkehiro@hotmil.com; Noritsugu Kunihiro nori9216@med.osk cu.c.jp; Kosuke Nkjo kousuke @yhoo.co.jp; Ichiro Kuki gpkichiro0926@yhoo.co.jp; Mstk Fukuok tktk_0730@yhoo.co.jp; Kenji Oht koht@med.osk cu.c.jp *Corresponding uthor Received: 24 Ferury 18 Accepted: 09 August 18 Pulished: 10 Septemer 18 Astrct Bckground: In the surgicl tretment of temporl loe epilepsy with mesil temporl loe tumor, whether to remove the hippocmpus iming for etter seizure outcome in ddition to removing the tumor is dilemm. Two peditric cses treted successfully with tumor removl lone re presented. Cse Description: The first cse ws n 11 yer old girl with gngliogliom in the left uncus, nd the second cse ws 9 yer old girl with pleomorphic xnthostrocytom in the left prhippocmpl gyrus. In oth cses, the hippocmpus ws not invded, merely compressed y the tumor. Tumor removl ws performed under intropertive electrocorticogrphy (ECoG) monitoring. After tumor removl, norml dischrges remined t the hippocmpus nd djcent temporl cortices, ut further surgicl interventions were not performed. The seizures disppered completely in oth cses. Conclusions: When we must decide whether to remove the hippocmpus, the side of the lesion, the severity nd chronicity of the seizures, nd the presence of invsion to the hippocmpus re the fctors tht should e considered. Anorml dischrges on ECoG t the hippocmpus or djcent cortices re one of the fctors relted to epileptogenicity, ut it is simply result of interictl irrittion, nd it is not n solute indiction for dditionl surgicl intervention. Videos ville on: Access this rticle online Wesite: DOI: /sni.sni_61_18 Quick Response Code: Key Words: Electrocorticogrphy, hippocmpectomy, mesil temporl loe tumor, surgicl strtegy, tumor relted epilepsy This is n open ccess journl, nd rticles re distriuted under the terms of the Cretive Commons Attriution-NonCommercil-ShreAlike 4.0 License, which llows others to remix, twek, nd uild upon the work non-commercilly, s long s pproprite credit is given nd the new cretions re licensed under the identicl terms. For reprints contct: reprints@medknow.com How to cite this rticle: Ud T, Kunihiro N, Nkjo K, Kuki I, Fukuok M, Oht K. Seizure freedom from temporl loe epilepsy with mesil temporl loe tumor y tumor removl lone without hippocmpectomy despite remining norml dischrges on intropertive electrocorticogrphy: Report of two peditric cses nd reconsidertion of the surgicl strtegy. Surg Neurol Int 2018;9: Surgicl Neurology Interntionl Pulished y Wolters Kluwer - Medknow

2 INTRODUCTION Tumors locted in the mesil temporl loe re often ssocited with temporl loe epilepsy (TLE). In these cses, ecuse the hippocmpus is locted close to the tumor, it my ply some role in generting, mplifying, or propgting seizures. In such cses, whether the tumor invdes to the hippocmpus is n importnt fctor in determining surgicl strtegy. When the tumor itself invdes to the hippocmpus, the surgicl strtegy is quite simple, tht is, removing oth the tumor nd the hippocmpus. On the other hnd, when the hippocmpus is intct or merely compressed y the tumor, there is dilemm s to whether to remove the hippocmpus iming for seizure free outcome. This is ecuse removl of hippocmpus with norml ppernce on preopertive imging generlly cuses memory decline, especilly on the dominnt side. [6,7,21] Therefore, the hippocmpus should e preserved s much s possile. However, in view of the seizure control rte, tumor removl with hippocmpectomy is reported to e etter thn tht without hippocmpectomy. [3,15,27] In previous reports, dditionl corticectomy or hippocmpectomy ws considered sed on intropertive electrocorticogrphy (ECoG). [1,9,16,18,22,26] However, when the hippocmpus just mplifies or propgtes seizures generted in the tumor, complete seizure free sttus cn e expected with tumor removl lone despite the ECoG findings. Two peditric cses of surgiclly treted TLE with mesil temporl loe tumor re reported. In oth cses, the seizures disppered completely fter surgery with removl of the tumor lone. Reviewing the literture nd our cses, the pproprite surgicl strtegy for TLE with mesil temporl loe tumor is discussed. CASE DESCRIPTION Cse 1 An 11 yer old girl presented with 3 yer history of complex prtil seizures (CPSs). The frequency of the seizures hd een less, ut it ws grdully incresing, nd t the time surgery ws considered, it ws once or twice dy. Despite nticonvulsnt therpy (levetircetm, 25 mg/kg/dy), the seizures were not controllle. Higher rin function hd not een evluted, ut no declines of cognitive nd memory functions were pprent, nd she hd fully norml school life except for the seizures. On electroencephlogrphy (EEG), norml proxysml spikes nd wves were locted with mximl mplitude t the left nterior temporl re. On preopertive imging, heterogeneously enhnced mss with some clcifiction ws locted in the left uncus [Figure 1 nd ]. The hippocmpus seemed not to e invded, merely compressed y the mss lesion. c Figure 1: Preopertive ( nd ) nd postopertive (c nd d) MRI in Cse 1: ( nd ) mixed intensity mss lesion is locted in the left uncus, ut the hippocmpus is intct, merely compressed y the lesion, nd (c nd d) the mss lesion hs een completely removed with trnssylvin pproch without ny dmge to the djcent cortices nd hippocmpus As n initil surgicl strtegy, removl of the tumor lone without hippocmpectomy ws chosen, nd if mediclly intrctle seizures remined fter tumor removl, surgicl intervention to the hippocmpus would e dded s the second surgery. The ptient ws plced in the supine position under generl nesthesi. For the intropertive ECoG, ntiepileptic drugs were discontinued on the morning of surgery. Sevoflurne ws mintined t 2.5% with n dequte muscle relxnt. End tidl CO 2 levels were mintined t round 30 mmhg. [8,10,13] A frontotemporl crniotomy ws performed using hlf coronl skin incision, nd the Sylvin fissure ws widely opened. Through the inferior peri insulr sulcus, the inferior horn of the lterl ventricle ws opened. Then, ECoG t the hippocmpus, s well s t the djcent temporl cortices, ws performed using strip electrodes with six contcts t 5 mm intervls nd four contcts t 1 cm intervls (Unique Medicl, Tokyo, Jpn). Proxysml typicl norml dischrges were seen on the hippocmpus, s well s djcent temporl cortices [Figure 2]. The tumor locted in the uncus ws completely removed. After tumor resection, norml dischrges on the hippocmpus nd djcent temporl cortices were reduced in frequency, ut remined [Figure 2]. As plnned, the hippocmpus ws left ehind without surgicl intervention [Video 1]. Postopertively, totl removl of the tumor without ny d

3 Figure 2: Intropertive electrocorticogrphy efore tumor removl () nd fter tumor removl () t the temporl cortex nd hippocmpus. () Proxysml norml dischrges re confirmed t the hippocmpus, s well s the temporl se nd lterl temporl cortex. () Anorml dischrges re less frequent compred with efore tumor removl, ut they remin t the hippocmpus, temporl se, nd lterl temporl cortex dmge to the djcent cortices nd hippocmpus ws confirmed on MRI [Figure 1c nd d]. On pthology, the dignosis ws gngliogliom, nd her seizures hd completely disppered (Engel clssifiction: [2] clss I) since the surgery for 22 months with sme dosge of levetircetm. She hd no memory dysfunction nd Krnofsky Performnce Scle [11] ws 100 postopertively. Cse 2 A 9 yer old girl presented with 1 yer history of CPSs. The frequency of the seizures ws twice or three times week. Sodium vlprote ws not effective, nd levetircetm ws dministered s second choice nticonvulsnt. However, despite tking levetircetm (35 mg/kg/dy), the seizures were uncontrollle. On Wechsler Intelligence Scle for Children IV, no declines of higher rin function or memory function were evident. On EEG, norml proxysml spikes nd wves were locted with mximl mplitude t the left middle temporl re. On preopertive imging, cystic mss with nodulr enhnced mss ws locted in the posterior prhippocmpl gyrus on the left side [Figure 3 nd ]. The hippocmpus ppered not to e invded, merely compressed y the mss lesion. In this cse s well, removl of the tumor lone without hippocmpectomy ws chosen s the initil surgery. The ptient ws plced in the right side semiprone prk ench position under generl nesthesi. As in the first cse, sevoflurne ws mintined t 2.5% for the intropertive ECoG. An occipito suoccipitl crniotomy on the left side ws mde using hockey stick skin incision. Through the suprcereellr trnstentoril route, the inferior surfce of the temporl loe ws exposed. ECoG ws then performed t the prhippocmpl nd fusiform gyri using strip electrode with four contcts t 1 cm intervls (Unique Medicl), nd norml dischrges c Figure 3: Preopertive ( nd ) nd postopertive (c nd d) MRI in Cse 2: ( nd ) n enhnced smll mss with cyst formtion is locted in the left posterior prhippocmpl gyrus, ut the hippocmpus is intct, merely compressed y the lesion, nd (c nd d) the mss lesion hs een completely removed with suprcereellr trnstentoril pproch without ny dmge to the djcent cortices nd hippocmpus were confirmed [Figure 4]. The tumor locted in the posterior prhippocmpl gyrus ws completely removed. After the tumor resection, norml dischrges remined t the fusiform gyrus [Figure 4]. However, s plnned, djcent cortex nd hippocmpus were left ehind without surgicl intervention [Video 2]. Postopertive MRI confirmed totl removl of the tumor without ny dmge to the djcent cortices nd hippocmpus [Figure 3c nd d]. On pthology, the dignosis ws pleomorphic xnthostrocytom, nd her seizures hd disppered completely (Engel s clssifiction: [2] clss I) since the surgery for 23 months. The dosge of levetircetm ws reduced to 10 mg/kg/dy. She hd no memory dysfunction nd Krnofsky Performnce Scle [11] ws 100 postopertively. DISCUSSION d In oth of the present cses, the tumors were successfully removed y trnssylvin trnsventriculr pproch nd suprcereellr trnstentoril pproch without hippocmpectomy, nd the seizures disppered completely postopertively. When the tumor is locted fr from the hippocmpus, for exmple on the lterl temporl loe or other prt of the rin, to evlute the seizure onset zone with chronic intrcrnil electrodes plcement nd susequent video, ECoG

4 monitoring is useful step to mke decision whether to remove the hippocmpus or not. However, in the cse of mesil temporl loe tumor, precise plcements of intrcrnil electrodes on or in the hippocmpus nd the tumor re much more difficult. Therefore, one stge surgery is thought to e preferred in the cse of TLE with mesil temporl loe tumor. As descried, whether to dd surgicl intervention to the djcent re with n norml ECoG fter tumor removl hs not een estlished. [1,9,16,18,22,26] Fctors tht should e considered in mking this decision re (1) the side of the lesion; (2) the durtion, severity, nd chronicity of the seizures; nd (3) the presence of invsion to the hippocmpus. In ddition, intropertive ECoG findings t the hippocmpus or djcent cortices re lso importnt. [14,20] This is ecuse, when the lesion is locted on the nondominnt side, removl of the hippocmpus does not led to severe memory dysfunction, nd when the seizures re not intrctle, the remining hippocmpus itself my not cuse seizures. In oth of the present cses, the lesions were locted on the dominnt side. Surgery hd een performed less thn 3 yers since seizure onset, nd the numer of nticonvulsnts tken efore surgery ws less thn two. The tumors did not invde to the hippocmpus, they merely compressed it. Intropertive ECoG findings my e vlule to identify the extent of the irrittive re to e removed, [1,3,4,14 16,18,20,22] ut they re just prt of n interictl recording over short time (usully 10 min t most). Severl studies demonstrted tht stisfctory seizure control ws chieved y removl of the tumor lone without intropertive ECoG monitoring. [1,5,12] Also, in our previous report, remining norml dischrges on ECoG t the temporl neocortex fter selective mygdlohippocmpectomy hd no reltionship to postopertive remining seizures. [25] Therefore, the decision ws mde to remove the tumor lone without hippocmpectomy despite remining norml dischrges on ECoG t the hippocmpus nd djcent cortices fter tumor removl. One solution for etter seizure outcomes is dding hippocmpl trnsection, which ws first reported in [19] Hippocmpl trnsection is procedure originlly developed for MRI negtive mesil TLE to preserve memory function. [17,24] In hippocmpl trnsection, the hippocmpus is not removed, just trnsected. The theory is tht the epileptogenic circuit is disrupted y prllel trnsection of the hippocmpus nd tht the memory circuit from the hippocmpus to the fornix vi the fimri is preserved. Recently, it hs lso een used for TLE with temporl loe tumor in some institutions. [23] However, hippocmpl trnsection is lso somewht invsive for the hippocmpus nd should e voided if possile. Finlly, we propose flowchrt of the surgicl strtegy for TLE with mesil temporl loe tumor, focusing on whether to remove the tumor lone or with hippocmpectomy, tking into ccount the side of the tumor, intrctility of seizures, nd the presence of tumor invsion to the hippocmpus [Figure 5]. According to this flowchrt, we consider preserving the hippocmpus s much s possile, especilly on the dominnt side, nd if intrctle seizures remin fter initil surgery, we consider removl or trnsection of the hippocmpus therefter. Surgeons should select the pproprite pproch for tumor removl with or without hippocmpectomy. It is still unknown tht wht percentge of the cses surgeons cn preserve hippocmpus when the norml dischrges still remin fter tumor removl in intropertive ECoG. To evlute the percentge nd verify the efficcy of our flowchrt, rndomized controlled study is mndtory to e performed. CONCLUSIONS For TLE with mesil temporl loe tumor on the dominnt side without invsion to the hippocmpus, Figure 4: Intropertive electrocorticogrphy efore tumor removl () nd fter tumor removl () t the temporl cortex. () Proxysml norml dischrges re confirmed t the fusiform gyrus. () Anorml dischrges re less frequent compred with efore tumor removl, ut they remin Figure 5: Flow chrt used to determine whether to remove the hippocmpus in the surgicl strtegy for temporl loe epilepsy with mesil temporl loe tumor

5 removl of tumor lone without hippocmpectomy cn e n pproprite initil surgicl strtegy. Anorml dischrges on intropertive ECoG t the djcent cortex or hippocmpus re one of the fctors relted to epileptogenicity, ut they re simply result of interictl irrittion. Therefore, one might conclude tht their presence is not n solute indiction for dding corticectomy or hippocmpectomy. Acknowledgment We thnk Drs. Hisshi Kwwki, Shin Okzki, Tkeshi Inoue, Megumi Nukui, Kiyohiro Kim, Ysuhiro Mtsusk, Syugo Nishijim, nd Sy Koh for their help with this study. Declrtion of ptient consent The uthors certify tht they hve otined ll pproprite ptient consent forms. In the form the ptient(s) hs/hve given his/her/their consent for his/her/ their imges nd other clinicl informtion to e reported in the journl. The ptients understnd tht their nmes nd initils will not e pulished nd due efforts will e mde to concel their identity, ut nonymity cnnot e gurnteed. Finncil support nd sponsorship Nil. Conflicts of interest There re no conflicts of interest. REFERENCES 1. Ctltepe O, Turnli G, Ylnizoglu D, Topçu M, Akln N. Surgicl mngement of temporl loe tumor relted epilepsy in children. J Neurosurg 2005;102: Engel J. Surgicl Tretment of the Epilepsies. New York: Rven Press; Englot DJ, Berger MS, Brro NM, Chng EF. Fctors ssocited with seizure freedom in the surgicl resection of glioneuronl tumors. Epilepsi 2012;53: Gelins JN, Bttison AW, Smith S, Connolly MB, Steinok P. Electrocorticogrphy nd seizure outcomes in children with lesionl epilepsy. Childs Nerv Syst 2011;27: Giulioni M, Glssi E, Zucchelli M, Volpi L. Seizure outcome of lesionectomy in glioneuronl tumors ssocited with epilepsy in children. J Neurosurg 2005;102: Gleissner U, Helmstedter C, Schrmm J, Elger CE. Memory outcome fter selective mygdlohippocmpectomy: A study in 140 ptients with temporl loe epilepsy. Epilepsi 2002;43: Helmstedter C, Petzold I, Bien CG. The cognitive consequence of resecting nonlesionl tissues in epilepsy surgery Results from MRI nd histopthology negtive ptients with temporl loe epilepsy. Epilepsi 2011;52: Herrick IA, Gel AW. Anesthesi for temporl loe epilepsy surgery. Cn J Neurol Sci 2000;27 Suppl 1:S Hu WH, Ge M, Zhng K, Meng FG, Zhng JG. Seizure outcome with surgicl mngement of epileptogenic gngliogliom: A study of 55 ptients. Act Neurochir (Wien) 2012;154: Jääskeläinen SK, Kisti K, Suni L, Hinkk S, Scheinin H. Sevoflurne is epileptogenic in helthy sujects t surgicl levels of nesthesi. Neurology 2003;61: Krnofsky DA, Burchenl JH. The Clinicl Evlution of Chemotherpeutic Agents in Cncer. In: C. M. McLeod, Ed., Evlution of Chemotherpeutic Agents, Columi University Press, New York,;1949. p Kim SK, Wng KC, Hwng YS, Kim KJ, Cho BK. Intrctle epilepsy ssocited with rin tumors in children: Surgicl modlity nd outcome. Childs Nerv Syst 2001;17: Kurit N, Kwguchi M, Hoshid T, Nkse H, Skki T, Furuy H, et l. The effects of sevoflurne nd hyperventiltion on electrocorticogrm spike ctivity in ptients with refrctory epilepsy. Anesth Anlg 2005;101: McKhnn GM 2 nd, Schoenfeld McNeill J, Born DE, Hglund MM, Ojemnn GA. Intropertive hippocmpl electrocorticogrphy to predict the extent of hippocmpl resection in temporl loe epilepsy surgery. J Neurosurg 2000;93: Moriok T, Hshiguchi K, Ngt S, Miygi Y, Yoshid F, Shono T, et l. Additionl hippocmpectomy in the surgicl mngement of intrctle temporl loe epilepsy ssocited with glioneuronl tumor. Neurol Res 2007;29: Ogiwr H, Nordli DR, DiPtri AJ, Alden TD, Bowmn RM, Tomit T, et l. Peditric epileptogenic gnglioglioms: Seizure outcome nd surgicl results. J Neurosurg Peditr 2010;5: Ptil AA, Andrews RV. Nonresective hippocmpl surgery for epilepsy. World Neurosurg 2010;74: Pilcher WH, Silergeld DL, Berger MS, Ojemnn GA. Intropertive electrocorticogrphy during tumor resection: Impct on seizure outcome in ptients with gnglioglioms. J Neurosurg 1993;78: Shimizu H, Kwi K, Sung S, Sugno H, Ymd T. Hippocmpl trnsection for tretment of left temporl loe epilepsy with preservtion of verl memory. J Clin Neurosci 2006;13: Southwell DG, Grci PA, Berger MS, Brro NM, Chng EF. Long term seizure control outcomes fter resection of gnglioglioms. Neurosurgery 2012;70: Stroup E, Lngfitt J, Berg M, McDermott M, Pilcher W, Como P, et l. Predicting verl memory decline following nterior temporl loectomy (ATL). Neurology 2003;60: Sugno H, Shimizu H, Sung S. Efficcy of intropertive electrocorticogrphy for ssessing seizure outcomes in intrctle epilepsy ptients with temporl loe mss lesions. Seizure 2007;16: Sugno H, Shimizu H, Sung S, Ari N, Tmgw K. Temporl loe epilepsy cused y dermoid cyst. Neurol Med Chir (Tokyo) 2006;46: Ud T, Morino M, Ito H, Minmi N, Hosono A, Ngi T, et l. Trnssylvin hippocmpl trnsection for mesil temporl loe epilepsy: Surgicl indictions, procedure, nd postopertive seizure nd memory outcomes. J Neurosurg 2013;119: Ud T, Morino M, Minmi N, Mtsumoto T, Uchid T, Kmei T, et l. Anorml dischrges from the temporl neocortex fter selective mygdlohippocmpectomy nd seizure outcomes. J Clin Neurosci 2015;22: Wllce D, Run D, Knner A, Smith M, Pitelk L, Stein J, et l. Temporl loe gnglioglioms ssocited with chronic epilepsy: Long term surgicl outcomes. Clin Neurol Neurosurg 2013;115: Wllce DJ, Byrne RW, Run D, Cochrn EJ, Roh D, Whisler WW, et l. Temporl loe pleomorphic xnthostrocytom nd chronic epilepsy: Long term surgicl outcomes. Clin Neurol Neurosurg 2011;113: