The supracerebellar-transtentorial approach to posteromedial temporal lesions in children with refractory epilepsy.
OBJECTIVE
Operations on tumors of the posteromedial temporal (PMT) region, that is, on those arising from the posterior parahippocampal, fusiform, and lingual gyri, are challenging to perform because of the deep-seated location of these tumors between critical cisternal neurovascular structures and the adjacent temporal and occipital cortexes. Traditional surgical approaches require temporal or occipital transgression, retraction, or venous sacrifice. These approaches may result in unintended complications that should be avoided. To avoid these complications, the supracerebellar-transtentorial (SCTT) approach to this region has been used as an effective alternative treatment in adult patients. The SCTT approach uses a sitting position that offers a direct route to the posterior fusiform and lingual gyri of the temporal lobe. The authors report the feasibility, safety, and efficacy of this approach, using a modified lateral park-bench position in a small cohort of pediatric patients.


METHODS
The authors carried out a retrospective case review of 5 consecutive patients undergoing a paramedian SCTT approach between 2009 and 2014 at the authors' institution.


RESULTS
The SCTT approach in the park-bench position was used in 3 boys and 2 girls with a mean age of 7.8 years (range 13 months to 16 years). All patients presented with a seizure disorder related to a tumor in a PMT region involving the parahippocampal and fusiform gyri of the left (n = 3) or right (n = 2) temporal lobe. No procedure-related complications were observed. Gross-total resection and control of seizures were achieved in all cases. Tumor classes and types included 1 Grade II astrocytoma, 1 pleomorphic xanthoastrocytoma, 1 ganglioglioma, and 2 glioneural tumors. None of the tumors had recurred by the mean follow-up of 22 months (range 1-48 months). Outcomes of epileptic seizures were excellent, with seizure symptoms in all 5 patients scoring in Engel Class IA.


CONCLUSIONS
The SCTT approach represents a viable option when resecting tumors in this region, providing a reasonable working corridor and low morbidity. The authors' experience in a cohort of pediatric patients demonstrates that complete resection of the lesions in this location is feasible and is safe when involving an approach that involves using a park-bench lateral positioning.
Division of Pediatric Neurosurgery, Department of Neurosurgery, Miller School of Medicine, University of Miami, Miami Children's Hospital, Miami, Florida.
Alexander G
AG
Weil
Andrew L
AL
Middleton
Toba N
TN
Niazi
John
J
Ragheb
Sanjiv
S
Bhatia
D000293:Adolescent; D001254:Astrocytoma / Q000150:complications / Q000601:surgery; D001932:Brain Neoplasms / Q000150:complications* / Q000473:pathology / Q000601:surgery*; D002531:Cerebellum / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D018303:Ganglioglioma / Q000150:complications / Q000601:surgery; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D019635:Neurosurgical Procedures / Q000379:methods*; D009778:Occipital Lobe / Q000601:surgery; D012189:Retrospective Studies; D013116:Spinal Cord / Q000601:surgery; D013702:Temporal Lobe / Q000601:surgery; D016896:Treatment Outcome
ECoG = electrocorticography; PHG = parahippocampal gyrus; PMT = posteromedial temporal; SCTT = supracerebellar-transtentorial; fusiform gyrus; hippocampus; oncology; parahippocampal gyrus; park-bench position; posteromedial temporal; refractory epilepsy; supracerebellar transtentorial; technique