Actually, TLS can be observed in about 10% of surgical cases of mTLE as an abnormal band of small and clustered “granular”

neurons in the outer part of cortical layer 2 (Fig. 8).[77] Single heterotopic neurons in subcortical white matter should be considered significant when their numbers in deep white matter are more than 30/mm2,[55] although their epileptogenic significance remains to be determined. For practical purposes, a panel of NeuN immunostaining may be useful to estimate the number of single heterotopic neurons in deep white matter (Fig. 9); however, reference photographs should be prepared by each laboratory as the actual magnification of photographs differs depending on the microscope and attached digital camera as well as the distance between the optical lens and digital camera. Finally, small “lentiform” heterotopia Nutlin3a is usually undetectable by MRI and histologically

composed of projecting neurons, which is distinct from the larger nodular heterotopia that is usually detectable by MRI and consists of both projecting and local circuit neurons.[78] Because of the similarity at a glance, it should not be mistaken for a part of the claustrum. Surgical pathology of mTLE-HS and FCD was briefly reviewed with some historical notes on their histological classifications and clinicopatholgical correlations, along with our recent attempts to construct a simplified classification system of HS and neuropathological comparative study on mTLE-HS and d-HS. However, the etiology and pathogenesis of most epileptogenic lesions, including mTLE-HS and FCD, are Ibrutinib cell line yet to be elucidated. This work was presented in part at the 53rd Annual Meeting of the Japanese Society of Neuropathology (Niigata, Japan, 2012) and was supported in part by grants from the Japan Epilepsy Research Foundation (H16-009 and H21-004 to HM), Encouragement Fund for Graduate

Students of Tottori University (to Dr. Manami Ueda, Neuropathology and Ophthalmology, Tottori University), Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan [17689040 to HM and 18790717 to Dr. Chitose Sugiura, Neuropathology and Child Neurology, Tottori University], and a grant Silibinin from the Collaborative Research Project [2011-2226 to HM and Dr. Akiyoshi Kakita, Brain Research Institute, Niigata University) of the Brain Research Institute, Niigata University, Japan. HVV was supported in part by the Daljit S. & Elaine Sarkaria Chair in Diagnostic Medicine, PHS grants [P50AG16570 and P01AG12435], and the UC Pediatric Neuropathology Consortium. We acknowledge helpful discussions with Drs Masae Ryufuku (Neuropathology, Research Institute for Brain and Blood Vessels – Akita), Emad S Farag (Neurology, UCLA Medical Center) and Eisaku Ohama (Professor Emeritus, Neuropathology, Tottori University).