Case ReportPattern of Corticospinal Projections Defined by Brain Mapping During Resective Epilepsy Surgery in a Patient with Congenital Hemiparesis and Intractable Epilepsy
Introduction
Many forms of prenatal and perinatal brain injury can lead to congenital hemiparesis. Periventricular white matter injury is the most common lesion type1; other causes include perinatal arterial stroke, brain malformations, and intracranial hemorrhage. Patients with congenital or early-onset brain structural lesions present with contralateral hemiparesis, cognitive deficits, developmental delays, and seizures. Seizure is the most debilitating manifestation and greatly impairs the quality of life in both the affected individuals and their caregivers and prevents them from active social participation.2, 3, 4 Children with epilepsy may also have cognitive and learning difficulties, leading to low academic performance in school and poor interpersonal relationships with peers.5 Antiepileptic drugs (AEDs), a ketogenic diet, nonspecific interventions, and surgery are the mainstays of treatment for seizures in childhood. Medication is usually the first-line treatment for confirmed and persistent seizures. Seizure control is achieved in 70%–80% of epileptic children with the first or second AED, and about two thirds of children who take AEDs can be weaned off after 2 years of being seizure-free.6 However, short-term and long-term adverse effects of AEDs often limit their use. AEDs can cause dose-dependent adverse effects, including cognitive decline, persistent somnolence, and ataxia as well as idiosyncratic responses such as Stevens-Johnson syndrome and chronic adverse effects, including altered hormonal regulation, weight gain, hair loss, and loss of bone density.7 Of all the known adverse effects, cognitive decline probably is the most significant in children because long-term developmental impairment can result.8 Thus, early-onset epilepsy disorder and its pharmacologic management intertwine to create a suboptimal situation for affected children.
If seizures cannot be managed by AEDs or the adverse effects of the AEDs are intolerable, surgical resection of the epileptogenic focus is the next option to achieve better seizure management. According to a meta-analysis conducted by Cao et al.,9 71% of epileptic children undergoing hemispheric surgery could maintain a seizure-free status in 5 years, an outstanding long-term prognosis. Nevertheless, surgical resection of the epileptogenic focus poses the risk of creating new functional deficits. However, it is possible that corticospinal projections of the lesioned hemisphere might migrate to the opposite hemisphere in younger individuals, owing to early onset of the lesions and children's pronounced neuroplasticity.10 This possibility should be considered in surgical decision making and may affect the prognosis of functional outcomes. In the present study, we employed an innovative intraoperative neurophysiologic monitoring approach to determine the pattern of corticospinal projections during resective surgery of an adult patient with congenital hemiparesis and refractory epilepsy. A thorough understanding of the anatomy is essential not only for surgical decision making but also for predicting functional outcomes after surgery.
Section snippets
History and Examination
A 34-year-old man was born full-term via normal spontaneous delivery. His mother denied any abnormality or events during perinatal follow-up examinations or postpartum. The patient had a history of developmental delay, right hemiparesis since infancy, and seizures starting at age 6 years. He developed dystonia of the right upper extremity in flexor posturing in adolescence; however, he could still walk a long distance with a hemiparetic gait and was partially independent in activities of daily
Discussion
Children with congenital or early-onset brain lesions frequently experience contralateral hemiparesis, mental deficits, and seizures, which have a tremendous impact on their development. Seizures increase caregivers' burden and negatively affect their quality of life.11, 12 Surgical resection of the epileptogenic focus is an alternative option if medical treatment fails to provide satisfactory control of seizure attacks.13, 14 However, resective surgery of the cortex carries the risk of
Conclusions
The main difference of our approach, in contrast to previous routine applications, is that we recorded CMAPs over the bilateral limb muscles simultaneously, instead of over the contralateral muscles only, to determine the corticospinal projection pattern. We believe that this technique has the potential to replace preoperative functional MRI and transcranial magnetic stimulation in resective epilepsy surgery, particularly for young patients. Not only can it improve the safety of surgical
References (20)
- et al.
Computed tomographic findings in congenital hemiparesis in childhood and their relation to etiology and prognosis
Neuropediatrics
(1981) - et al.
Depressive symptoms among mothers of children with epilepsy: a review of prevalence, associated factors, and impact on children
Epilepsia
(2009) - et al.
Even a single seizure negatively impacts pediatric health-related quality of life
Epilepsia
(2009) Long-term outcome of epilepsy
Epileptic Disord
(2000)- et al.
Cognitive outcome in childhood-onset epilepsy: a five-decade prospective cohort study
J Int Neuropsychol Soc
(2017) - et al.
Factors predicting prognosis of epilepsy after presentation with seizures
Ann Neurol
(2000) - et al.
Adverse effects of antiepileptic drugs
Acta Neurol Scand Suppl
(2005) - et al.
Cognitive side effects of antiepileptic drugs in children
Neurology
(2004) - et al.
Five-year long-term prognosis of epileptic children after hemispheric surgery: a systematic review and meta-analysis
Medicine (Baltimore)
(2016) - et al.
Two types of ipsilateral reorganization in congenital hemiparesis: a TMS and fMRI study
Brain
(2002)
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Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.