Surgical outcome in patients with epilepsy and dual pathology

Abstract

High-resolution MRI can detect dual pathology (an extrahippocampal lesion plus hippocampal atrophy) in about 5-20% of patients with refractory partial epilepsy referred for surgical evaluation. We report the results of 41 surgical interventions in 38 adults (mean age 31 years, range 14-63 years) with dual pathology. Three patients had two operations. The mean postoperative follow-up was 37 months (range 12-180 months). The extrahippocampal lesions were cortical dysgenesis in 15, tumour in 10, contusion/infarct in eight and vascular malformation in five patients. The surgical approach aimed to remove what was considered to be the most epileptogenic lesion, and the 41 operations were classified into lesionectomy (removal of an extrahippocampal lesion); mesial temporal resection (removal of an atrophic hippocampus); and lesionectomy plus mesial temporal resection (removal of both the lesion and the atrophic hippocampus). Lesionectomy plus mesial temporal resection resulted in complete freedom from seizures in 11/15 (73%) patients, while only 2/10 (20%) patients who had mesial temporal resection alone and 2/16 (12.5%) who had a lesionectomy alone were seizure-free (P< 0.001). When classes I and II were considered together results improved to 86, 30 and 31%, respectively. Our findings indicate that in patients with dual pathology removal of both the lesion and the atrophic hippocampus is the best surgical approach and should be considered whenever possible.

Coexistent pathology in chronic epilepsy patients with neoplasms

“…[7][8][9][10] In a subset of these tumors, which are generally low-grade glial or glioneuronal neoplasms, multiple pathologies, which potentially may contribute to the genesis of these seizures, are identifiable (dual pathology). [11][12][13][14][15][16] Among these, there is a well-established association of certain neoplasms with malformations of cortical development (cortical dysplasia), particularly dysembryoplastic neuroepithelial tumors and gangliogliomas. [17][18][19][20] The purpose of this study is to systematically review one institution's experience with neoplasms associated with identifiable coexistent pathology arising in the setting of chronic epilepsy.…”

Temporal lobe epilepsy associated with 'triple pathology' of hippocampal sclerosis, focal cortical dysplasia and cavernoma in the ipsilateral frontal lobe

“…Dual pathology does not merely indicate the anatomical coexistence of HS with an extrahippocampal lesion, but also pathophysiological mechanisms such as the kindling phenomenon and secondary hippocampal epileptogenesis [9,10,11,12]. Dual pathology is almost exclusively found in patients with congenital extrahippocampal lesions or occurs early in life, suggesting that the hippocampus is more vulnerable and more likely to develop HS in early childhood [3].…”

“…Nevertheless, Salanova et al [3] showed that resection of both lesions led to an excellent outcome, with 70.2% of patients becoming seizure-free and 21.6% having only rare seizures, while none of the patients with non-resected extrahippocampal lesions became seizure-free. Furthermore, Li et al [11] demonstrated that 73% of patients with both lesions resected became seizure-free, compared with 20% of patients with only the medial temporal structures resected and 12.5% of patients with only the extrahippocampal lesion resected. The investigators thus concluded that removal of both lesions is the best surgical approach, and should be considered whenever possible.…”

Surgical and postmortem pathology studies: contribution for the investigation of temporal lobe epilepsy

“…The injuries diagnosis associated with MTS has great clinical importance, due to its impact in response to clinical treatment 71 and programming of surgery 72,73 . The association of MTS plus another lesion out of the hippocampus constitutes dual pathology 73,74 , which was seen in 5 to 30% of patients with focal epilepsy and drug-resistant seizures 74 . MTS may be associated with several other pathologies, such as MCD, slow growth tumors, vascular malformations, porencephaly, and gliosis [72][73][74][75][76] .…”