Clinical characteristics and surgical outcomes of epilepsy associated with temporal encephalocele: A systematic review.

Temporal encephaloceles (TE) are an under-identified, potentially intervenable cause of epilepsy. This systematic review consolidates the current data to identify the major clinical, neuroimaging, and EEG features and surgical outcomes of epilepsy associated with TE. Literature searches were carried out using MEDLINE, Embase, PsycINFO, Scopus, and Cochrane Library databases from inception to December 7, 2023. Studies were included if they described clinical, neuroimaging, EEG, or surgical data in ≥5 patients with TE and epilepsy. Of 562 studies identified in the search, 24 met the eligibility criteria, reporting 423 unique patients with both epilepsy and TE. Compared to epilepsy patients without TE, those with TE had a higher mean age of seizure onset and were less likely to have a history of febrile seizures. Seizure semiologies were variable, but primarily mirrored temporal lobe onset patterns. Epilepsy patients with TE had a higher likelihood of having clinical or radiographic features of idiopathic intracranial hypertension (IIH) than those without. Brain MRI may show ipsilateral mesial temporal sclerosis (16 %). CT scans of the skull base usually revealed bony defects near the TE (90 %). Brain PET scans primarily showed ipsilateral temporal lobe hypometabolism (80 %), mostly in the anterior temporal lobe (67 %). Scalp EEG mostly lateralized ipsilateral to the implicated TE (92 % seizure onset) and localized to the temporal lobe (96 %). Intracranial EEG revealed seizure onset near the TE (11 of 12 cases including TE-adjacent electrodes) with variable timing of spread to the ipsilateral hippocampus. After surgical treatment of the TE, the rate of Engel I or ILAE 1 outcomes at one year was 75 % for lesionectomy, 85 % for anterior temporal lobectomy (ATL), and 80 % for ATL with amygdalohippocampectomy. Further studies are needed to better elucidate the relationship between IIH, TE, and epilepsy, improve the identification of TE, and optimize surgical interventions.

Surgical Outcomes of Retinal Detachment in Knobloch Syndrome.

PURPOSE: To describe the rate, characteristics, and outcomes of rhegmatogenous retinal detachment (RD) in patients with Knobloch syndrome. DESIGN: A single-center retrospective cohort study. PARTICIPANTS: Fifty patients with Knobloch syndrome diagnosed clinically, with or without molecular confirmation of recessive pathogenic COL18A1 variants. METHODS: A retrospective chart review of all patients diagnosed with Knobloch syndrome from November 1, 1983 to March 31, 2023. Demographic data, ophthalmic evaluation at baseline and follow-up, interventions, and final anatomic and visual outcomes were collected. MAIN OUTCOME MEASURES: Rate, time of onset, characteristics, and treatment outcomes of RD. RESULTS: Fifty patients with Knobloch syndrome were included. Males constituted 56% of cases. The diagnosis was confirmed with molecular genetic testing in 37 (74%) patients. Twenty-two patients (44%) had documented occipital bony defects or scalp lesions. Forty-eight of 100 eyes (48%) developed RD at a mean (standard deviation [SD]) age of 6.5 (6.1) years. The mean (SD) follow-up was 7.7 (5.6) years (range, 6 months to 24.3 years). Macular hole-related RD comprised 33% of RD cases. The overall single-surgery success rate was 36% and the final anatomic success rate was 70%. Macular hole-related RD carried a slightly worse prognosis with a 58% final anatomic success rate. Vitrectomy with adjunct scleral buckle and silicone oil tamponade provided the highest single-surgery success (62.2%). In eyes with measurable best-corrected visual acuity (BCVA), the mean preoperative BCVA was 1.2 logarithm of the minimum angle of resolution (Snellen equivalent, 20/320). After successful repair, mean visual acuity was 1.3 logarithm of the minimum angle of resolution (Snellen equivalent, 20/500). CONCLUSIONS: Retinal detachment in Knobloch syndrome is frequent and occurs in young children. Macular hole-related RD comprises one third of RD cases and requires careful macular evaluation. Vitrectomy, combined with scleral buckling and silicone oil tamponade, appears to provide the best anatomic outcomes. FINANCIAL DISCLOSURES: The authors have no proprietary or commercial interest in any materials discussed in this article.

RESOLUTION OF CALVARIAL HYPEROSTOSIS IN AFRICAN LION CUBS (PANTHERA LEO LEO) AFTER VITAMIN A SUPPLEMENTATION.

Two female (FL 1, FL 2) and one male (ML) 11-wk-old, intact, captive African lion cubs (Panthera leo leo) were presented with a history of mild vestibular signs. Initial serum vitamin A concentrations were low (140 nmol/L) for ML. Calvarial hyperostosis was confirmed using computed tomography (CT) of the head and cervical vertebrae in each cub. CT measurements were adapted in relation to the skull width. ML showed the most pronounced thickening of the tentorium cerebelli and occipital bone, represented by a tentorium cerebelli to skull width ratio (TCR) of 0.08 (FL 1: 0.06, FL 2: 0.05) and a basisphenoid to skull width ratio (BBR) of 0.07 (FL 1: 0.06, FL 2: 0.04). Magnetic resonance imaging (MRI) revealed cerebellar herniation and cervical intramedullary T2-weighted hyperintensity from C1, extending caudally for at least two cervical vertebrae in all cubs. Treatment was initiated with subcutaneous vitamin A supplementation and feeding of whole carcasses. Improvement in ataxia was noticed 3 wk later. Follow-up CT and MRI examinations were performed in ML after 3 and 8 mon. The affected bones appeared slightly less thickened and TCR and BBR had decreased to 0.05 after 3 mon. The cerebellum remained mildly herniated, accompanied by amelioration of cervical T2w hyperintensities. After 8 mon, evaluation and diagnostic imaging revealed further improvement regarding the neurologic status and measurements (TCR 0.05, BBR 0.04) despite persistence of a subtle cerebellar herniation. In conclusion, bone remodeling and improvement in clinical signs may be achievable in young lion cubs presented with calvarial hyperostosis and may be attributable to high-dose vitamin A supplementation.

The Role of Lumbar Drains in the Perioperative Management of Primary Spontaneous Temporal Lobe Encephaloceles and Cerebrospinal Fluid Leaks.

OBJECTIVE: To examine the role of lumbar drains (LDs) in the success of spontaneous temporal cerebrospinal fluid (CSF) leak and encephalocele repair. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary academic health system. PATIENTS: Patients undergoing repair of spontaneous temporal lobe encephaloceles or middle fossa CSF leaks during years 2017 to 2023. INTERVENTIONS: Transmastoid, middle fossa craniotomy, or combination approaches to CSF leak repair. OUTCOME MEASURES: Failure rate, complication rate, length of stay (LOS), readmission. RESULTS: Sixty-nine patients were included, with a combination approach performed in 78.3%, transmastoid in 17.4%, and isolated middle fossa craniotomy in 4.3%. Mean body mass index was 33.2, mean bony defect size width was 6.51 mm, and defect locations included the epitympanum, antrum, mastoid, and petrous apex. Multilayer closure with three or more layers was performed in 87.0%. LD was used in 73.9% of cases for a mean duration 2.27 days and was associated with longer LOS (3.27 vs. 1.56 d, p = 0.006) but not with failure rate, complications, discharge destination, or readmission. Only one major complication occurred as a result of the drain, but low-pressure headache was anecdotally common. CONCLUSIONS: Use of LD in the repair of spontaneous CSF leaks and temporal lobe encephaloceles is associated with longer LOS but not failure rates or other admission-level outcomes.

[Surgical treatment of focal drug-resistant epilepsy associated with temporal lobe encephalocele]. / Khirurgicheskoe lechenie patsientov so strukturnoi fokal'noi farmakorezistentnoi epilepsiei, assotsiirovannoi s visochnymi entsefalotsele.

BACKGROUND: In recent years, temporal lobe encephalocele has become more common in patients with focal drug-resistant epilepsy. Despite available experience, there are still no clear recommendations for choosing the extent of surgery in these patients. OBJECTIVE: To evaluate the effectiveness of diagnosis and surgical treatment of focal drug-resistant epilepsy associated with temporal lobe encephalocele. MATERIAL AND METHODS: The study included 21 patients with focal temporal lobe epilepsy and temporal lobe encephalocele. All patients underwent continuous video-EEG monitoring and MRI of the brain. There were 12 (57.4%) selective encephalocele resections and 9 (42.6%) anterior temporal lobectomies. The median follow-up period was 31 months. RESULTS: The overall effectiveness of surgical treatment with postoperative Engel class I was 76% (16 cases). Selective encephalocele resection was followed by postoperative Engel class I in 10 patients (83%). There were 6 (67%) patients with similar outcomes after temporal lobectomy. Mean volume of resected tissue adjacent to encephalocele was 8.3 cm3. CONCLUSION: Surgery is a highly effective treatment for patients with epileptic seizures following temporal lobe encephalocele. In our sample, favorable postoperative outcomes were achieved in 76% of patients (Engel class I). There were no significant differences in effectiveness between selective resection and temporal lobectomy. Further research is necessary for a clear protocol of surgical treatment of focal drug-resistant epilepsy associated with encephalocele.

Semiautomated electric source imaging determines epileptogenicity of encephaloceles in temporal lobe epilepsy.

OBJECTIVE: We aimed to assess the ability of semiautomated electric source imaging (ESI) from long-term video-electroencephalographic (EEG) monitoring (LTM) to determine the epileptogenicity of temporopolar encephaloceles (TEs) in patients with temporal lobe epilepsy. METHODS: We conducted a retrospective study involving 32 temporal lobe epilepsy patients with TEs as potentially epileptogenic lesions in structural magnetic resonance imaging scans. Findings were validated through invasive intracerebral stereo-EEG in six of 32 patients and postsurgical outcome after tailored resection of the TE in 17 of 32 patients. LTM (mean duration = 6 days) was performed using the 10/20 system with additional T1/T2 for all patients and sphenoidal electrodes in 23 of 32 patients. Semiautomated detection and clustering of interictal epileptiform discharges (IEDs) were carried out to create IED types. ESI was performed on the averages of the two most frequent IED types per patient, utilizing individual head models, and two independent inverse methods (sLORETA [standardized low-resolution brain electromagnetic tomography], MUSIC [multiple signal classification]). ESI maxima concordance and propagation in spatial relation to TEs were quantified for sources with good signal quality (signal-to-noise ratio > 2, explained signal > 60%). RESULTS: ESI maxima correctly colocalized with a TE in 20 of 32 patients (62.5%) either at the onset or half-rising flank of at least one IED type per patient. ESI maxima showed propagation from the temporal pole to other temporal or extratemporal regions in 14 of 32 patients (44%), confirming propagation originating in the area of the TE. The findings from both inverse methods validated each other in 14 of 20 patients (70%), and sphenoidal electrodes exhibited the highest signal amplitudes in 17 of 23 patients (74%). The concordance of ESI with the TE predicted a seizure-free postsurgical outcome (Engel I vs. >I) with a diagnostic odds ratio of 2.1. SIGNIFICANCE: Semiautomated ESI from LTM often successfully identifies the epileptogenicity of TEs and the IED onset zone within the area of the TEs. Additionally, it shows potential predictive power for postsurgical outcomes in these patients.

Atretic cephalocele associated with sinus pericranii: a single-center analysis.

PURPOSE: The purpose of this report is to investigate the association of atretic cephalocele (AC) with sinus pericranii (SP) in order to improve the management of AC. METHODS: Pediatric patients with AC who underwent repair surgeries were retrospectively analyzed. Anomalies including SP were evaluated using computed tomography angiography and venography (CTA/V) as well as magnetic resonance imaging. RESULTS: Fourteen patients were identified, comprising of 5 males and 9 females. The AC was located interparietally in 8 cases and occipitally in 6 cases. Seven cases (50%) were found to be associated with SP, all of which did not involve major intracranial venous circulation. Five out of 8 parietal ACs (63%) were accompanied by SP, while 2 out of 6 occipital ACs (33%) exhibited SP. All of the SP associated with AC only contributed to a small portion of the venous outflow, and the repair surgeries were successfully performed without excessive bleeding. CONCLUSION: More than half of the ACs were associated with SP, with a higher prevalence in the parietal region compared to the occipital region. For the appropriate management of AC, preoperative investigation of SP using CT venography is considered important.

A rare case of occipital encephalocele presenting as the largest congenital head mass in an infant.

BACKGROUND: The prevalence of encephalocele is estimated to be 0.8-5.0 per 10,000 live births. The most frequent encephalocele is the occipital encephalocele. It is a congenital neural tube defect characterized by the protrusion or herniation of intracranial contents through a cranial defect. The term "giant/massive/large encephalocele" is used to describe an encephalocele that is significantly larger than the size of the head. CASE DESCRIPTION: A 2-month-old male infant presented in the neurosurgery outpatient department with one of the largest head masses over the posterior aspect since birth. The swelling was gradually progressive and developed ulceration over the swelling with intermittent cerebrospinal fluid (CSF) discharge but no associated weakness in limbs. Magnetic Resonance Imaging (MRI) brain showed a large occipital meningoencephalocele containing predominantly cyst with part of the cerebellar and occipital lobe. The surgery was planned. The sac contained CSF with the gliotic occipital lobe. The sac and gliotic brain tissue was excised. He had an uneventful postoperative course. CONCLUSION: Surgery serves several functions, including reducing the torque and weight of the head to allow for more normal motor development, removal of the thin, leaking scalp and dural closure to prevent CSF leak and subsequent infection, and improving the cosmetic and social issues that the child and family may have to endure.

Pathogenesis and treatment of a giant occipital bone defect with meningoencephalocele in an NF1 child: case report and review of the literature.

Autosomal dominantly inherited neurofibromatosis type I (NF1) is a systemic disorder caused by a mutation of a gene on chromosome 17q11.2 and characterized by multiple café-au-lait spots, lentiginous macules, Lisch nodules of the iris, and tumors of the nervous system. Bony manifestations such as scoliosis, dysplasia of the greater sphenoidal wing, tibial pseudoarthrosis, short stature, and macrocephaly have been reported in approximately 50% of patients. However, calvarial bone defects are rare. After screening 324 articles, 23 cases (12 adult and 11 pediatric patients) of occipital bone defects in NF1 patients were selected. All patients had a single/multiple bone defect over the lambdoid suture. Adjacent benign plexiform neurofibromas were observed in 14 patients (60.8%, 7 adults and 7 children); one adult patient was diagnosed with neurofibrosarcoma. Meningoencephalocele over the occipital defect was noted in 8 cases (34.78%, all adults). Cranioplasty was performed in only 17.39% of patients. Histologic examination was performed in 7 of the 15 patients with associated neurofibromas/neurofibrosarcomas. Biopsy of the bone margins surrounding the defect was performed in only one case. Pathologic examination of the herniated parieto-occipital or cerebellar tissue was not performed in any of the patients studied. We report the case of a 9-year-old girl with NF1 and a significant occipital bone defect and performed a systematic review of the relevant literature to highlight the challenges in treating this condition and to investigate the underlying mechanisms contributing to bone defects or dysplasia in NF1.

Intrauterine Correction of Fetal Myelomeningocele Through Minihysterotomy.

Spina bifida is the most common congenital central nervous system anomaly, resulting in lifelong neurologic, urinary, motor, and bowel disability.1 Its most frequent form is myelomeningocele, characterized by spinal cord extrusion into a sac filled with cerebrospinal fluid.1 We report the case of a 28-year-old pregnant female with no comorbidities. At 16 weeks of pregnancy, fetal ultrasound presented ventriculomegaly, cerebellar herniation, and lumbar myelomeningocele. At 22 weeks, intrauterine surgical correction was performed (Video 1). A minihysterotomy spanning approximately 3 cm was performed. The defect was opened, and the neural placode was dissected and released. This was followed by the isolation of the peripheric dura, which was molded into a tube and closed with watertight suture. Finally, the minihysterotomy was sutured and the skin was closed. The pregnancy followed its course with no complications, and the child was born at term with the lesion closed and no necessity of intensive care. Recent studies have demonstrated that infants who undergo open in utero myelomeningocele repair have better neurologic outcomes than those who are treated after birth.1,2 However, maternal morbidity is nonnegligible with the classical open surgery.2 Peralta et al2 propose a modification of the classic 6.0- to 8.0-cm hysterotomy in which the same multilayer correction of the spinal defect is performed through a 2.5- to 3.5-cm hysterotomy. This modification, called minihysterotomy, has been successfully performed outside of its creation center and was associated with reduced risks of preterm delivery and maternal, fetal, and neonatal complications.2,3.

Meckel-Gruber syndrome together with Dandy-Walker malformation: an atypical case report of a 2nd recurrence in a consanguine marriage.

Meckel-Gruber syndrome is a lethal disorder characterized by occipital encephalocele, polycystic kidneys, and polydactyly. In most cases, it is identified and terminated antenatally. In this report, the authors present a case of Meckel-Gruber syndrome together with Dandy-Walker malformation. A pregnant woman referred at the 28th week of gestation with an abnormal ultrasound scan showing posterior encephalocele and bilaterally enlarged kidneys. Further imaging also indicated communication between the 4th ventricle and posterior cerebellar cerebrospinal fluid space, after which the fetus was diagnosed with Meckel-Gruber syndrome and Dandy-Walker malformation. Pregnancy termination was refused by the parents and the offspring was prematurely born to be the 2nd recurrence of Meckel-Gruber syndrome in this consanguine family. Remarkably, at the 3 different pregnancies, ultrasound was inconclusive before the 7th month of gestation. Though up to date Meckel-Gruber syndrome is ultimately lethal, the lifespan of affected newborns varied greatly. We suggest developing a severity classification to estimate life expectancy in unterminated cases.

Multiple skull base defects in the setting of spontaneous cerebrospinal fluid rhinorrhea; a dual institution view.

PURPOSE: Idiopathic intracranial hypertension (IIH) is a condition of high cerebrospinal fluid (CSF) pressure that presents with CSF leak. The implications of multiple skull base defects (SBD) and associated synchronous CSF leaks have not been previously explored. MATERIALS AND METHODS: A dual institutional case-control study examined multiple SBD's and encephaloceles on the risk of CSF leak and postoperative failures post-repair. IIH patients with CSF leaks and IIH controls without leaks were selected retrospectively. Chi square analysis evaluated for statistically significant alterations in probability with CSF leak development. RESULTS: 192 patients were selected with 108 IIH controls and 84 spontaneous CSF leak cases. Signs and symptoms for IIH controls and CSF leak cases respectively were pulsatile tinnitus (60.2 % and 29.8 %), headaches (96.3 % and 63.1 %), papilledema (74.1 % and 12.5 %), visual field defects (60.8 % and 13 %) (p < 0.001). Encephalocele formation in controls was 3.7 % compared to cases at 91.6 % (p < 0.001). Multiple SBD's in controls compared cases was 0.9 % and 46.4 % respectively (p < 0.001). Subgroup analysis of CSF leak cases showed 15 patients with two CSF leak repairs due to a recurrence. 27 (39.1 %) single leak cases had multiple SDB's while 12 (80 %) recurrent leaks had multiple SDB's (p = 0.004). CONCLUSIONS: Patients with radiographic evidence of multiple SBD's and encephaloceles represent a high-risk population with a propensity for CSF leaks. Secondary SBD's are common in patients with spontaneous CSF rhinorrhea and higher in patients with a recurrence.

How I do it? Endoscopic endonasal transpterygoid repair of sphenoid lateral recess cerebrospinal fluid leak after previous unsuccessful transcranial surgery.

BACKGROUND: Direct access to the sphenoid lateral recess offers the best chance of sealing spontaneous cerebrospinal fluid (CSF) rhinorrhea caused by lateral sphenoid encephaloceles of the Sternberg canal defect. METHOD: We present a case of spontaneous left-sided sphenoid lateral recess CSF leak after previous unsuccessful transcranial surgery managed with an endoscopic endonasal transpterygoid approach (EETA). An anatomical-based step-by-step illustration of the EETA was presented in the surgical video. CONCLUSION: This case demonstrates the value of endoscopic endonasal transpterygoid corridor in the exposure and manipulation of the sphenoid lateral recess.

Drug-resistant temporal lobe epilepsy with temporal encephaloceles: How far to resect.

PURPOSE: This study sought to evaluate the impact of surgical extent on seizure outcome in drug-resistant temporal lobe epilepsy (DR-TLE) with temporal encephaloceles (TE). METHODS: This was a single-institution retrospective study of patients who underwent surgery for DR-TLE with TE between January 2008 and December 2020. The impact of surgical extent on seizure outcome was evaluated. In a subset with dominant DR-TLE, the impact of surgical extent on neuropsychometric outcome was evaluated. RESULTS: Thirty-four patients were identified (female, 56%; median age at surgery, 43 years). TE were frequently overlooked on initial magnetic resonance imaging (MRI), with encephaloceles only detected after repeat or expert re-review of MRI, additional multi-modal imaging, or intra-operatively in 31 (91%). Sixteen (47%) underwent limited resections, including encephalocele resection only (n = 5) and encephalocele resection with more extensive temporal corticectomy sparing the amygdala and hippocampus (n = 11). The remainder (n = 18, 53%) underwent standard anterior temporal lobectomy and amygdalohippocampectomy (ATLAH). Limited resection was performed more frequently on the left (12/17 vs. 4/17, p = 0.015). Twenty-seven patients (79%) had a favourable outcome (Engel I/II), and 17 (50%) were seizure-free at the last follow-up (median seizure-free survival of 27.3 months). There was no statistically significant difference in seizure-free outcomes between limited resection and ATLAH. In dominant DR-TLE, verbal memory decline was more likely after ATLAH than limited resection (3/4 vs. 0/9, p = 0.014). CONCLUSION: Expert re-review of imaging and multi-modal advanced imaging improved TE identification. There was no statistical difference in seizure-free outcomes based on surgical extent. Preservation of verbal memory supports limited resection in dominant temporal cases.

Bullous Aplasia Cutis as a Presenting Sign of Encephalocele.

This case report describes a congenital cystic scalp nodule on a 2-week-old infant.

The Predictors of Seizures in Patients with Encephalocele: An 11-Year Experience from a Tertiary Hospital.

INTRODUCTION: The aim of the study was to investigate and identify the predictors associated with the incidence of seizures in patients with encephalocele (EC). METHODS: A retrospective analysis was undertaken of patients treated for EC at a tertiary medical center in Tehran between 2010 and 2021. Data including age at presentation, gender, location, size, and content of EC, ventriculomegaly, hydrocephalus, associated anomalies, and neurodevelopmental delay (NDD) were evaluated for their prognostic value. In addition, univariate and multivariate analyses were performed to identify the correlation between independent predictors and seizure incidence. RESULTS: One hundred and two cases of EC were identified. Seventy-one ECs (69.6%) were posterior ECs, while 31 (30.4%) were anterior. Neural tissue was found in 43 (42.2%) of the ECs. Thirty-three patients (32.4%) had ventriculomegaly, of which 90.9% underwent shunt placement for progressive or symptomatic hydrocephalus. Seizure was found in 26 (25.5%) patients. On univariate analysis, presence of other anomalies, postoperative infections, and NDD were associated with seizures (p < 0.05). When the anomalies were categorized into intracranial and extracranial groups in univariate analysis, none was associated with statistically significant increase in seizure (p values of 0.09 and 0.61, respectively). Although according to multivariate analysis, only the association between other associated anomalies and seizure was near significant (OR: 2.0, 95% CI: 0.95-4.2, p = 0.049). Children with NDD and postoperative infection were, respectively, 3.04 and 1.3 times more at risk to experience seizures compared to other patients. CONCLUSION: We found a rate of 25.5% risk of seizure in patients with EC. This study could not find any significant predictors of seizure in children with EC. However, pediatric patients with postoperative infections including sepsis, wound infection, and NDD require more consideration to reduce the risk of seizure.

Distinctive electro-clinical, neuroimaging and histopathological features of temporal encephaloceles associated to epilepsy.

OBJECTIVE: Encephaloceles (ENCs) may cause clinical complications, including drug-resistant epilepsy that can be cured with epilepsy surgery. METHODS: We describe clinical, diagnostic, and neuropathological findings of 12 patients with temporal ENC and epilepsy evaluated for surgery and compare them with a control group of 26 temporal lobe epilepsy (TLE) patients. RESULTS: Six patients had unilateral and 6 bilateral temporal ENCs. Compared to TLEs, ENCs showed i) later epilepsy onset, ii) higher prevalence of psychiatric comorbidities, iii) no history of febrile convulsions, and iv) ictal semiology differences. Seven patients had MRI signs of gliosis, and 9 of intracranial hypertension. Interictal EEG analysis in ENCs demonstrated significant differences with controls: prominent activity in the beta/gamma frequency bands in frontal regions, interictal short sequences of low-voltage fast activity, and less frequent and more localized interictal epileptiform discharges. Ictal EEG patterns analyzed in 9 ENCs showed delayed and slower contralateral spread compared to TLEs. All ENCs that underwent surgery (7 lobectomies and 1 lesionectomy) are in Engel class I. Neuropathological examination revealed 4 patterns: herniated brain fragments, focal layer I distortion, white matter septa extending into the cortex, and altered gyral profile. CONCLUSIONS AND SIGNIFICANCE: The described peculiarities might help clinicians to suspect the presence of largely underdiagnosed ENCs.