Interhemispheric Vertical Hemispherotomy: A Single Center Experience

Abstract

Purpose: Hemispheric epileptogenic lesions such as hemimegalencephaly often manifest as intractable epilepsy in early infancy. Hemispherotomy is the treatment of choice for controlling intractable hemispheric epilepsy. Less invasive procedures are desirable for surgery on infants with low body weight. This study compared our experience with interhemispheric vertical hemispherotomy (IVH) and peri-insular lateral hemispherotomy (PIH). Methods: Thirteen consecutive patients underwent hemispherotomy for treatment of intractable epilepsy in our institution between 2001 and 2012. The etiology of epilepsy included hemimegalencephaly in 7 patients and cortical dysplasia in 3. PIH was performed on the first 5 patients and IVH on the last 8 patients. In the latter procedure, complete section of the corpus callosum was first performed via the interhemispheric approach. After removing part of the cingulate gyrus, section of the descending fibers was performed anterolaterally to the thalamus. Clinical characteristics, duration of operation and amount of blood transfusion were compared between the PIH and IVH groups. Results: There was no difference in age at surgery, body weight and age of epilepsy onset between the two groups. No surgery-related death was observed. No patients required shunt operation. One patient who underwent IVH required reoperation for incomplete disconnection. The amount of intraoperative blood transfusion was smaller and the total duration of operation was shorter in the IVH group than in the PIH group. Conclusion: The interhemispheric approach minimizes cortical resection and may be less invasive than PIH. IVH is advantageous for treating infants with low body weight.

Comparison of the real‐world effectiveness of vertical versus lateral functional hemispherotomy techniques for pediatric drug‐resistant epilepsy: A post hoc analysis of the HOPS study

“…Our findings contrast two studies directly comparing vertical and lateral techniques, which found favorable outcomes overall but no differences between groups. One of these studies was underpowered to detect differences in seizure outcome, 24 whereas the other was a national multicenter study comprising 90 patients across three main Italian epilepsy centers with a methodology similar to ours. 20 Our calculated rates of seizure freedom at the last follow‐up for vertical (86.1%) and lateral (79.0%) approaches were almost identical to the latter study, which had 84.2% and 73.1% seizure freedom in the vertical and lateral groups, respectively; however, the utilization of a modified interhemispheric approach by de Palma et al yielded a much lower rate of seizure freedom for their vertical group overall and may explain the different conclusions between our findings.…”

“…Intraoperative blood transfusion and the total duration of surgery have been shown to be less in vertical hemispherotomy. 24 Increased blood loss in lateral hemispherotomy is thought to be associated with the greater amount of tissue resected, with the exception of the keyhole technique. 19 The risk of hydrocephalus is thought to be higher in lateral hemispherotomy due to resection of the subarachnoid space of the Sylvian fissure, although the 2%–20% rate of hydrocephalus in lateral series 16 , 17 , 19 , 38 , 39 appears to be comparable with 3%–16% in vertical series.…”

Surgical Treatments for Epilepsies in Children Aged 1–36 Months

“…33 We used a stringent definition of seizure freedom, which required studies using the Engel classification to report Engel Ia. However, if we had considered Engel I as seizure freedom, seizure freedom in Pinto et al 33 would increase to 66% (10 of 15); also, 4 other studies 19,22,25,31 reporting rates of 55%-81% (consistent with the range of seizure freedom rates we already identified) would have been included.…”

“…Favorable outcome after epilepsy surgery could depend on multiple factors, including underlying etiology. Eight studies 21,22,24,26,31,32,34 for HME, 92% (12/13) for FCD/MCD without HME, and 93% (13/14) for other pathology.…”

Epilepsy surgery in children under 3 years of age: surgical and developmental outcomes

“…7,8 VPH was later introduced according to the method of Delalande et al 9,10 A technical modification was made as reported elsewhere and was applied in some patients. 11 Posterior quadrantectomy was performed in patients with a posterior quadrantic epileptogenic lesion. The technical details are as previously reported.…”