Knobloch Syndrome, a Rare Cause of Occipital Encephalocele and Seizures: A Case Report

Abstract

<b><i>Background:</i></b> Knobloch syndrome (KS) is a rare autosomal recessive disorder associated with multiple ocular and cranial abnormalities. Occult occipital skull defect or encephalocele should raise suspicion of this disease. It is never reported in neurosurgical literature, possibly due to a lack of clinician familiarity, leading to underdiagnosis and inadequate management. Our patient also had seizures, which is a sporadic presentation of this syndrome. <b><i>Case Description:</i></b> Here, we report a clinico-radiologic finding of a 7-year-old boy who presented with seizures, cataracts, and an occipital bone defect along with bilateral subependymal heterotopias and polymicrogyria. <b><i>Conclusions:</i></b> This case highlights the importance of consideration of this syndrome in children with a midline occipital bone defect with or without encephalocele and seizures. Early recognition of this presentation is critical for obtaining access to appropriate genetic counseling and subsequent monitoring and prevention of complications by surgical intervention.

The Predictors of Seizures in Patients with Encephalocele: An 11-Year Experience from a Tertiary Hospital

“…Contrarily to the above findings, Da Silva et al [31] found no association between seizures and NDD ( p = 0.12). However, there are several studies that have reported patients with ECs and associated anomalies who developed seizures and NDD [22, 41, 44].…”

“…However, there are notable cases in pediatric patients with a history of ECs and the occurrence of seizures [2, 21–27]. The main differences between seizure in adult and pediatric ECs lie not only in the onset of symptoms but also in the size of EC and other associated anomalies like hydrocephalus and intracranial/extracranial anomalies [21, 22, 28]. Most EC-related seizures in pediatric patients occur after resection of the EC [23–25, 29].…”

“…Contrarily, medial temporal ECs commonly present with seizures/epilepsy that are often intractable to medications and mostly require surgical intervention [16, 17, 33–36]. Interestingly, ECs of several locations including the motor cortex [30], frontal [37], or occipital lobe [3, 22, 24, 29] have also been reported to cause seizures. However, besides the vast knowledge about surgical repair for temporal EC associated with intractable seizures [6, 11, 13, 15–17, 20, 21], little is known about the proper management of seizures in children with EC before and after EC resection.…”