Table 1.

Summary of discussed operations.

Operations	Indications	Seizure Freedom Rate	Consistent Predictors of Success	References
Lesionectomy	Well-defined and radiographic ally apparent lesions Examples: focal cortical dysplasia, low-grade tumors, cavernous malformations, and AVMs	60–100%	Gross total resection (vs. subtotal)	[6–15,18]
Temporal Lobectomy Selective Amygdalohippocampectomy Temporal Lobe Disconnection	Small lesions limited to the temporal lobe Examples: mesial temporal sclerosis, low-grade tumors, cortical dysplasia, AVMs, gliosis, heterotopia, trauma, tuberous sclerosis, and neurofibromatosis	76%^a	Visible lesion Lack of secondary generalization Lack of bilateral involvement	[20,21,23–28,34,35]
Extratemporal Cortical Resection	Small lesions in an area other than the temporal lobe Examples: low-grade tumors, cortical dysplasia, AVMs, porencephalic cysts, gliosis, heterotopia, trauma, perinatal insults, and tuberous sclerosis	56%^a	Short epilepsy duration Lesional etiology Lack of secondary generalization Ictal EEG localization Frontal location	[38–48,50]
Posterior Quadrantectomy Posterior Quadrantotomy	Large unilateral lesions involving the posterior quadrant (posterior temporal, parietal, and occipital lobes) Examples: large cortical dysplasia, large tumors, leptomeningeal angiomas (Sturge-Weber), AVMs, trauma, and perinatal insults	50–92%	-	[52–63]
Anatomical Hemispherectomy Hemispherotomy	Large, (usually) unilateral lesions involving the majority of a patient’s hemisphere Examples: large cortical dysplasia, hemimegalencephaly, perinatal insults, Rasmussen’s encephalitis, and leptomeningeal angiomas (Sturge-Weber)	50 – 85%	Acquired/progressive etiology Unilateral EEG involvement No history of other resections	[68–73,75,76,79–83]
Corpus Callosotomy	Used for pathologies that cause a significant number of “drop-attacks” and are otherwise non-amenable to potentially-curative resection	18.8% (overall)^a 55.3% (“drop-attacks”)*	Infantile spasms (all seizures) Normal MRI (all seizures) Short duration (all seizures) Complete callosotomy (“drop-attacks”) Idiopathic etiology (“drop-attacks”)	[86–88,90–92,99,102]
Multiple Subpial Transections	Used when the epileptogenic zone is located in the eloquent cortex Often used to complement resection in cortical dysplasia, tumors, post-infectious epilepsy, and trauma Controversial use in Landau-Kleffner Syndrome	23.9% (without resection)^a 55.2% (with resection)^a	-	[110–115,117–119]

Reported in a recent systematic review of the procedure type.