Feasibility of Tailored Unilateral Disconnection vs Callosotomy for Refractory Epilepsy in Patients with Bilateral Parieto-Occipital Gliosis Following Perinatal Insult

BACKGROUND

Patients with perinatal hypoxia (PH) and drug-refractory epilepsy (DRE) often have bilateral parieto-occipital gliosis. Surgical management of such patients is a dilemma.

OBJECTIVE

To identify preoperative determinants for unilateral disconnection vs callosotomy, and analyze the surgical outcome in such patients.

METHODS AND MATERIAL

This was a retrospective analysis of patients with DRE and history of PH, with MRI abnormalities restricted to bilateral posterior quadrants. Preoperative semiology, epilepsy duration and seizure frequency were recorded. Based on the concordance between the results of non-invasive tests, patients underwent either posterior quadrant disconnection (PQD) or corpus callosotomy (CC). Preoperative variables were analyzed and corelated to the postoperative seizure freedom.

RESULTS

Fourteen patients were identified, 6 underwent PQD and 8 underwent CC. At follow up of 39.17 ± 23.75 months, 66.66% of patients (4/6) in the PQD subgroup had an ILAE Class I outcome. While none in the CC group attained seizure freedom, 87.5% (7/8) had more than 50% reduction in seizure frequency (follow up: 42 ± 27.31 months). Patients with a poor outcome had significantly greater seizure frequency (P = 0.05) and history of drop attacks (P = 0.04) in both the groups. Magnetoencephalography (MEG) accurately localized the epileptogenic zone in all of the patients with good outcome (P = 0.015). Concordance with single photon emission tomography (SPECT) was also a predictor of favorable outcome (P = 0.041).

CONCLUSIONS

A history of drop attacks with high seizure frequency is associated with poor postoperative seizure outcome. Unilateral PQD is feasible and leads to superior seizure-free outcomes, even in cases with widespread and bilateral imaging and electrical abnormalities, provided the other preoperative investigations are concordant in localizing the epileptogenic zone.

Endoscopic Hemispherotomy for Nonatrophic Rasmussen's Encephalopathy

Background

Hemispheric disconnection represents a challenging and major epilepsy surgical procedure. This procedure in experienced hands offers excellent results in terms of seizure outcomes, especially for hemispheric pathologies such as Rasmussen's encephalitis, hemispheric dysplasias, hemimegalencephaly. The technique of hemispherotomy has witnessed various modifications over the years, beginning from anatomical hemispherectomy to the current era of minimally invasive functional hemispheric disconnections.

Objective

This study aimed to describe the technique of performing endoscopic vertical hemispherotomy using interhemispheric corridor developed by the senior author.

Materials and Methods

A 12-year-old girl with seizure onset at the age of 10 years presented with an aura of fear and nausea followed by tonic deviation of eyes to the right and blinking with speech arrest. There were tonic-clonic movements of the right-sided limbs along with ictal spitting and occasional deviation of the angle of mouth to the right. The patient had loss of awareness for the event along with postictal confusion lasting few minutes.

Results

Video electroencephalography (VEEG) revealed left parietocentral and left temporal localization. Serial magnetic resonance imaging (MRI) brain over 3 years revealed progressive left hemispheric changes suggestive of Rasmussen's encephalitis. The patient underwent left-sided endoscopic hemispherotomy. At 2 years follow-up, the patient is seizure-free (ILAE [International League Against Epilepsy] Class 1).

Conclusion

Endoscopic hemispherotomy using the interhemispheric approach is an elegant, minimally invasive, reproducible, safe, and efficacious technique.

The development and efficacy of a mobile phone application to improve medication adherence for persons with epilepsy in limited resource settings: A preliminary study

OBJECTIVE

Persons with epilepsy (PWE), especially those with limited education backgrounds from developing countries, are challenged by complicated medication regimens, debilitating seizures, and stigmatization in their daily life. Consequently, it is difficult for physicians to ensure medication adherence. This study validates a novel mobile application which was hypothesized to increase medication adherence and self-management skills in PWE. Created by medical professionals, the application included behavioral and educational components and was built to be easy-to-understand for those of socio-economically disadvantaged backgrounds.

METHODS

This was a parallel, two-armed randomized controlled trial in which a total of 96 participants were enrolled from a Neurology Outpatient Department into a control standard care group and a mobile application group that used the smartphone application (app) in addition to the standard medical treatment. The app was intuitive and easy to understand for those coming from a socio-economically disadvantaged background. Medication adherence and self-efficacy were assessed with the Morisky Green and Levine Scale (MGLS) and the Epilepsy Self Efficacy Scale (ESES). Patients were reassessed 12 weeks later. Change in seizure frequency following administration of the application was a secondary outcome.

RESULTS

In an intent-to-treat analysis, the mobile application interventional group showed over a 60% increase in the proportion of medication adherence (P < 0.0001). The mean self-efficacy score for the mobile application group was increased from 269.5 to 289.75 (P < 0.0001). The control group showed no statistically significant increases in either the proportion adherent or mean self-efficacy scores.

SIGNIFICANCE

This study demonstrated the statistically significant performance of a mobile application in improving medication adherence and self-management skills in Indian persons with epilepsy.

Epilepsy surgery in COVID times-a unique conundrum

The COVID-19 pandemic has forced hospitals to prioritize admissions. Epilepsy surgeries have been postponed at most centers. As the pandemic continues with no definite end in sight in the near future, the question arises until when such patients should be denied appropriate treatment. A 12-year-old child with left-sided Rasmussen's encephalitis with drug refractory epilepsy (DRE) presented at the height of the pandemic, with worsening of seizure frequency from 4-5/day to 20/day, with new-onset epilepsia partialis continua. She demonstrated features of progressive cognitive decline. The pros and cons of operating during the pandemic were discussed with the parents by a multidisciplinary team. She underwent endoscopic left hemispherotomy. Postoperatively she became seizure free but developed hospital-acquired mild COVID infection for which she was treated accordingly. Chosen cases of severe DRE, as the one illustrated above, who are deemed to benefit from surgery by a multidisciplinary team of physicians, should be re-categorized into the most severe class of patients and scheduled for surgery as soon as possible. The risk benefit ratio of the seizures being mitigated by surgery on one hand and possibility of acquiring COVID infection during hospital stay has to be balanced and a decision made accordingly.

Posterior quadrant disconnection for sub-hemispheric drug refractory epilepsy

The posterior quadratic epilepsy (PQE) is a form of a multilobar epilepsy, involving the temporal-parietal and occipital lobes. Basically, epilepsies with localized networks to the posterior temporal, posterior parietal, and occipital lobes can benefit from this type of surgery. Gliosis due to perinatal insult and cortical dysplasis and angiomas in Sturge Weber syndrome involving the PQ have often been cited in the literature as the etiology for PQE. However, before considering surgery, it is important to localize the epileptogenic focus through a complete pre operative work up involving; EEG (Electro-Encephalo-Graphy), video EEG, single photon emission computed tomography (SPECT), positron emission tomography (PET), and magneto encephalography (MEG). Historically, these pathologies were dealt with multi-lobar resections, which were associated with high morbidity and mortality, owing to blood loss, especially in young children, hydrocephalus, and hemosiderosis. Based on the theory of networks involved in epileptogenesis, the concept of disconnection in epilepsy surgery was introduced. Delalande and colleagues, described the technique of hemispheric disconnection (functional hemispherectomy) for pathologies like: hemimegalencephaly, rasmussens encephalitis involving the entire hemisphere. The technique has evolved with time, moving towards minimally invasive endoscopic vertical hemispherotomy, described by Chandra and colleagues.^[1],[2] The posterior quadrant disconnection (PQD) evolved as a tailored disconnection on similar lines as hemispherotomy, for managing refractory epilepsy arising from the posterior quadrant.^[3] The technique and principles involved in the PQD surgery are similar to the those of peri-insular hemispherotomy and has been described in the literature by few authors.^{[3],[4],[5],[6]} The technique of performing PQD will be described here in a step-wise fashion with illustrations supplemented by a surgical video.