Sulcus-centered resection for focal cortical dysplasia type II: surgical techniques and outcomes

Focal cortical dysplasia type II (FCD II) is a common histopathological substrate of epilepsy surgery. Here, the authors propose a sulcus-centered resection strategy for this malformation, provide technical details, and assess the efficacy and safety of this technique. The main purpose of the sulcus-centered resection is to remove the folded gray matter surrounding a dysplastic sulcus, particularly that at the bottom of the sulcus. The authors also retrospectively reviewed the records of 88 consecutive patients with FCD II treated with resective surgery between January 2015 and December 2018. The demographics, clinical characteristics, electrophysiological recordings, neuroimaging studies, histopathological findings, surgical outcomes, and complications were collected. After the exclusion of diffusely distributed and gyrus-based lesions, 71 patients (30 females, 41 males) who had undergone sulcus-centered resection were included in this study. The mean (± standard deviation) age of the cohort was 17.78 ± 10.54 years (38 pediatric patients, 33 adults). Thirty-five lesions (49%) were demonstrated on MRI; 42 patients (59%) underwent stereo-EEG monitoring before resective surgery; and 37 (52%) and 34 (48%) lesions were histopathologically proven to be FCD IIa and IIb, respectively. At a mean follow-up of 3.34 ± 1.17 years, 64 patients (90%) remained seizure free, and 7 (10%) had permanent neurological deficits including motor weakness, sensory deficits, and visual field deficits. The study findings showed that in carefully selected FCD II cases, sulcus-centered resection is an effective and safe surgical strategy.

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Cortical Dyplasia: Complete Resection Correlates with Outcome…But, Complete Resection of What?

Epilepsy Currents ◽

10.1111/j.1535-7511.2009.01306.x ◽

2009 ◽

Vol 9 (4) ◽

pp. 100-102 ◽

Cited By ~ 2

Author(s):

Theodore H. Schwartz

Keyword(s):

Fdg Pet ◽

Pediatric Patients ◽

Focal Cortical Dysplasia ◽

Cortical Dysplasia ◽

Seizure Outcome ◽

Type I ◽

Type Ii ◽

Presurgical Evaluation ◽

Mri Scans

Incomplete Resection of Focal Cortical Dysplasia Is the Main Predictor of Poor Postsurgical Outcome. Krsek P, Maton B, Jayakar P, Dean P, Korman B, Rey G, Dunoyer C, Pacheco-Jacome E, Morrison G, Ragheb J, Vinters HV, Resnick T, Duchowny M. Neurology 2009;72(3):217–223. BACKGROUND: Focal cortical dysplasia (FCD) is recognized as the major cause of focal intractable epilepsy in childhood. Various factors influencing postsurgical seizure outcome in pediatric patients with FCD have been reported. OBJECTIVE: To analyze different variables in relation to seizure outcome in order to identify prognostic factors for selection of pediatric patients with FCD for epilepsy surgery. METHODS: A cohort of 149 patients with histologically confirmed mild malformations of cortical development or FCD with at least 2 years of postoperative follow-up was retrospectively studied; 113 subjects had at least 5 years of postoperative follow-up. Twenty-eight clinical, EEG, MRI, neuropsychological, surgical, and histopathologic parameters were evaluated. RESULTS: The only significant predictor of surgical success was completeness of surgical resection, defined as complete removal of the structural MRI lesion (if present) and the cortical region exhibiting prominent ictal and interictal abnormalities on intracranial EEG. Unfavorable surgical outcomes are mostly caused by overlap of dysplastic and eloquent cortical regions. There were nonsignificant trends toward better outcomes in patients with normal intelligence, after hemispherectomy and with FCD type II. Other factors such as age at seizure onset, duration of epilepsy, seizure frequency, associated pathologies including hippocampal sclerosis, extent of EEG and MRI abnormalities, as well as extent and localization of resections did not influence outcome. Twenty-five percent of patients changed Engel's class of seizure outcome after the second postoperative year. CONCLUSIONS: The ability to define and fully excise the entire region of dysplastic cortex is the most powerful variable influencing outcome in pediatric patients with focal cortical dysplasia. FDG-PET/MRI Coregistration Improves Detection of Cortical Dysplasia in Patients with Epilepsy. Salamon N, Kung J, Shaw SJ, Koo J, Koh S, Wu JY, Lerner JT, Sankar R, Shields WD, Engel J Jr, Fried I, Miyata H, Yong WH, Vinters HV, Mathern GW. Neurology 2008;71(20):1594–1601. OBJECTIVE: Patients with cortical dysplasia (CD) are difficult to treat because the MRI abnormality may be undetectable. This study determined whether fluorodeoxyglucose (FDG)-PET/MRI coregistration enhanced the recognition of CD in epilepsy surgery patients. METHODS: Patients from 2004–2007 in whom FDG-PET/MRI coregistration was a component of the presurgical evaluation were compared with patients from 2000–2003 without this technique. For the 2004–2007 cohort, neuroimaging and clinical variables were compared between patients with mild Palmini type I and severe Palmini type II CD. RESULTS: Compared with the 2000–2003 cohort, from 2004–2007 more CD patients were detected, most had type I CD, and fewer cases required intracranial electrodes. From 2004–2007, 85% of type I CD cases had normal non–University of California, Los Angeles (UCLA) MRI scans. UCLA MRI identified CD in 78% of patients, and 37% of type I CD cases had normal UCLA scans. EEG and neuroimaging findings were concordant in 52% of type I CD patients, compared with 89% of type II CD patients. FDG-PET scans were positive in 71% of CD cases, and type I CD patients had less hypometabolism compared with type II CD patients. Postoperative seizure freedom occurred in 82% of patients, without differences between type I and type II CD cases. CONCLUSIONS: Incorporating fluorodeoxyglucose-PET/MRI coregistration into the multimodality presurgical evaluation enhanced the noninvasive identification and successful surgical treatment of patients with cortical dysplasia (CD), especially for the 33% of patients with nonconcordant findings and those with normal MRI scans from mild type I CD.

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Predictors of surgical outcome in focal cortical dysplasia and its subtypes

Journal of Neurosurgery ◽

10.3171/2020.12.jns203385 ◽

2021 ◽

pp. 1-11

Author(s):

Sita Jayalakshmi ◽

Sudhindra Vooturi ◽

Rammohan Vadapalli ◽

Sailaja Madigubba ◽

Manas Panigrahi

Keyword(s):

Surgical Outcome ◽

Focal Cortical Dysplasia ◽

Cortical Dysplasia ◽

Seizure Freedom ◽

Type I ◽

Incomplete Resection ◽

Type Ii ◽

Type Iii ◽

Clear Cut

OBJECTIVE The authors analyzed predictors of surgical outcome in patients with focal cortical dysplasia (FCD) and its ILAE (International League Against Epilepsy) subtypes after noninvasive multimodal evaluation and calculated time to first seizure. METHODS Data of 355 patients with refractory epilepsy, confirmed FCD pathology, and 2–13 years of postsurgical follow-up were analyzed to determine the predictive roles of clinical, EEG, imaging, and surgical factors that influence seizure freedom. RESULTS The mean ± SD age at surgery was 20.26 ± 12.18 years. In total, 142 (40.0%) patients had daily seizures and 90 (25.3%) had multiple seizure types. MRI showed clear-cut FCD in 289 (81.4%) patients. Pathology suggested type I FCD in 27.3% of patients, type II in 28.4%, and type III in 42.8% of patients. At latest follow-up, 72.1% of patients were seizure free and 11.8% were seizure free and not receiving antiepileptic drugs. Among the subtypes, 88.8% of patients with type III, 69.3% with type II, and 50.5% with type I FCD were seizure free. Multiple seizure types, acute postoperative seizures (APOS), and type I FCD were predictors of persistent seizures, whereas type III FCD was the strongest predictor of seizure freedom. Type I FCD was associated with daily seizures, frontal and multilobar distribution, subtle findings on MRI, incomplete resection, and persistent seizures. Type II and III FCD were associated with clear-cut lesion on MRI, regional interictal and ictal EEG onset pattern, focal pattern on ictal SPECT, complete resection, and seizure freedom. Type III FCD was associated with temporal location, whereas type I and II FCD were associated with extratemporal location. Nearly 80% of patients with persistent seizures, mostly those with type I FCD, had their first seizure within 6 months postsurgery. CONCLUSIONS Long-term seizure freedom after surgery can be achieved in more than two-thirds of patients with FCD after noninvasive multimodal evaluation. Multiple seizure types, type I FCD, and APOS were predictors of persistent seizures. Seizures recurred in about 80% of patients within 6 months postsurgery.

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Transcriptomic profiling of high- and low-spiking regions reveals novel epileptogenic mechanisms in focal cortical dysplasia type II patients

Molecular Brain ◽

10.1186/s13041-021-00832-4 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Arpna Srivastava ◽

Krishan Kumar ◽

Jyotirmoy Banerjee ◽

Manjari Tripathi ◽

Vivek Dubey ◽

...

Keyword(s):

Rna Sequencing ◽

Focal Cortical Dysplasia ◽

Phospholipid Metabolism ◽

Cortical Dysplasia ◽

Type Ii ◽

Tissue Samples ◽

Significant Enrichment ◽

Gene Expression Studies ◽

Oligodendrocyte Development ◽

High Throughput Gene Expression

AbstractFocal cortical dysplasia (FCD) is a malformation of the cerebral cortex with poorly-defined epileptogenic zones (EZs), and poor surgical outcome in FCD is associated with inaccurate localization of the EZ. Hence, identifying novel epileptogenic markers to aid in the localization of EZ in patients with FCD is very much needed. High-throughput gene expression studies of FCD samples have the potential to uncover molecular changes underlying the epileptogenic process and identify novel markers for delineating the EZ. For this purpose, we, for the first time performed RNA sequencing of surgically resected paired tissue samples obtained from electrocorticographically graded high (MAX) and low spiking (MIN) regions of FCD type II patients and autopsy controls. We identified significant changes in the MAX samples of the FCD type II patients when compared to non-epileptic controls, but not in the case of MIN samples. We found significant enrichment for myelination, oligodendrocyte development and differentiation, neuronal and axon ensheathment, phospholipid metabolism, cell adhesion and cytoskeleton, semaphorins, and ion channels in the MAX region. Through the integration of both MAX vs non-epileptic control and MAX vs MIN RNA sequencing (RNA Seq) data, PLP1, PLLP, UGT8, KLK6, SOX10, MOG, MAG, MOBP, ANLN, ERMN, SPP1, CLDN11, TNC, GPR37, SLC12A2, ABCA2, ABCA8, ASPA, P2RX7, CERS2, MAP4K4, TF, CTGF, Semaphorins, Opalin, FGFs, CALB2, and TNC were identified as potential key regulators of multiple pathways related to FCD type II pathology. We have identified novel epileptogenic marker elements that may contribute to epileptogenicity in patients with FCD and could be possible markers for the localization of EZ.

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Genome-wide DNA Methylation and RNAseq Analyses Identify Aberrant Signalling Pathways in Focal Cortical Dysplasia (FCD) Type II

Scientific Reports ◽

10.1038/s41598-018-35892-5 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 7

Author(s):

Aparna Banerjee Dixit ◽

Devina Sharma ◽

Manjari Tripathi ◽

Arpna Srivastava ◽

Debasmita Paul ◽

...

Keyword(s):

Dna Methylation ◽

Focal Cortical Dysplasia ◽

Cortical Dysplasia ◽

Signalling Pathways ◽

Type Ii ◽

Genome Wide

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Surgical outcomes in children with bottom-of-sulcus dysplasia and drug-resistant epilepsy: a retrospective cohort study

Journal of Neurosurgery Pediatrics ◽

10.3171/2021.2.peds20967 ◽

2021 ◽

pp. 1-11

Author(s):

Puneet Jain ◽

Ayako Ochi ◽

Carter McInnis ◽

Hiroshi Otsubo ◽

O. Carter Snead ◽

...

Keyword(s):

Surgical Treatment ◽

Medical Records ◽

Focal Cortical Dysplasia ◽

Seizure Freedom ◽

Language Mapping ◽

Resective Surgery ◽

Histological Data ◽

Drug Resistant Epilepsy ◽

Video Eeg

OBJECTIVE Bottom-of-sulcus dysplasia (BOSD) is challenging to identify radiologically. The aim of this study was to explore seizure outcomes after resective surgery or MR-guided laser interstitial thermal therapy (MRgLITT) in children with BOSD. METHODS Children with radiologically defined BOSD who underwent resective surgery or MRgLITT, with at least 1 year of follow-up were included. Clinical, radiological, neurophysiological, and histological data were extracted from medical records. Invasive video EEG (IVEEG) was used to evaluate the ictal onset zone or motor/language mapping, wherever appropriate. Histology of MRI-visible BOSD, including the overlying and adjacent cortex, was also evaluated. RESULTS Forty-one children with BOSD underwent surgical treatment. The lesion was initially overlooked on MRI in 20 patients (48.8%). Of 34 patients who underwent IVEEG and who had available ictal data, the ictal onset zone extended beyond the MRI-visible BOSD in 23 patients (67.6%). Surgical treatment included lesionectomy (24 patients), extended lesionectomy (12 patients), lobectomy (1 patient), and ablation of BOSD (4 patients). The pathology in 37 patients who underwent resection showed focal cortical dysplasia type IIB and type IIA in 21 (53.8%) and 16 patients (41%), respectively. Seizure freedom was achieved in 32 patients (78.1%) after a mean follow-up of 4.3 years. CONCLUSIONS Seizure outcomes after resective surgery or MRgLITT in children with BOSD were generally favorable. The authors found that the neurophysiological abnormality and pathology often extended beyond the MRI-visible BOSD.

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