Etiology and Age Modifies Subjective Visual Function After Cerebral Hemispherectomy

Abstract

Background: Cerebral hemispherectomy is typically used to treat patients with pharmacoresistant epilepsy. Visual-related outcomes are relatively unstudied in this population, aside from the knowledge that patients develop a complete homonymous hemianopia contralateral to the side of the hemispherectomy. The purpose of this study was to determine and characterize parent-reported functional visual, oculomotor, and postural changes in a large population of patients following cerebral hemispherectomy. Methods: An online survey was sent to parents of children who had undergone hemispherectomy for seizure control. Families were recruited by the Brain Recovery Project: Childhood Epilepsy Surgery Foundation. Parent-reported subjective visual function was assessed by the presence of peripheral field defects, ocular misalignment and anomalous head posture. Results: A total of 196 (12.5%) participants responded. Postoperative follow-up was 92±78 months (range: 1-382). Ninety-three percent of parents reported the child had difficulties with peripheral vision. Torticollis was present postoperatively in 122 (62%) patients. Strabismus was noted in 93 (49%). Fifty-five (59%) of the strabismus patients demonstrated exotropia with the majority of exotropia patients demonstrating the exo-deviated eye in the direction contralateral to the hemispherectomy (74.5%). Both torticollis and strabismus were most frequently seen immediately after surgery. Sixty-six patients (34%) underwent strabismus treatment. Patients with younger age of seizure onset, younger age of surgery, and certain epilepsy etiologies (hemimegencephaly, Sturge-Weber syndrome) were more likely to develop strabismus and torticollis. Conclusions: Torticollis and strabismus are common after hemispherectomy and appear to be influenced by etiology and age at surgery. Preoperative discussion with parents and patients regarding those compensatory mechanisms is recommended, and postoperative ophthalmologic assessments are also encouraged.

Functional hemispheric disconnection procedures for chronic epilepsy: history, indications, techniques, complications and current practice in Europe. A consensus statement on behalf of the EANS functional neurosurgery section

“…These symptoms occurred more frequently in dominant hemisphere involvement. Postoperative visual field and/or visual acuity worsening has been demonstrated in pediatric series ( Chen et al, 2019 ; Meer et al, 2021 ). Chen et al (2019) reported that 49 % of their pediatric cases developed de novo or had worsening of their preoperative strabismus.…”

“…Postoperative visual field and/or visual acuity worsening has been demonstrated in pediatric series ( Chen et al, 2019 ; Meer et al, 2021 ). Chen et al (2019) reported that 49 % of their pediatric cases developed de novo or had worsening of their preoperative strabismus. It is of interest, that the vast majority of these patients developed torticollis from compensating for their visual deficits ( Chen et al, 2019 ).…”

“… Chen et al (2019) reported that 49 % of their pediatric cases developed de novo or had worsening of their preoperative strabismus. It is of interest, that the vast majority of these patients developed torticollis from compensating for their visual deficits ( Chen et al, 2019 ). Similarly, Meer et al (2021) reported in their pediatric series that 56 % of their cases had decreased visual acuity after surgery, 71 % experienced new visual field deficits while visual field impairment preexisted in others ( Meer et al, 2021 ).…”