Abstracts

Rationale:
Hypothalamic hamartoma (HH) is a rare cause of epilepsy, with an estimated prevalence of ~1 in 200,000. It is highly associated with neurodevelopmental disabilities, and may occasionally be associated with dysmorphology syndromes. HH is classically associated with gelastic seizures; other seizure types also develop in the majority of patients. Here we present a summary of patients with HH and epilepsy in New York with emphasis on clinical presentation and treatment outcomes.
Method:
The Rare Epilepsies in New York City (RENYC) database includes clinical notes for people with epilepsy from 5 academic medical centers in Manhattan and Bronx, NY from 2010-2014, including: Weill Cornell Medicine, Columbia University Medical Center, Montefiore Medical Center, New York University Langone Medical Center, and Mount Sinai Medical Center. In prior work, clinical notes were reviewed using keyword search and chart review to identify people with 30 rare causes of epilepsy. For this project we reviewed all cases with any of the terms: “Pallister-Hall”, “hypothalamic hamartoma”, “gelastic epilepsy”, “gelastic seizure”, “hypothalamic lesion.” Initially two reviewers (NB & DH) reviewed each chart to determine if there was hypothalamic hamartoma. If they disagreed, a third reviewer (ZG) reviewed the chart. A fourth reviewer (JB) reviewed charts in detail to extract and describe clinical features.
Results:
Twenty patients were identified. Four were excluded: 3 without clear imaging report of HH, 1 with HH but no seizures. Clinical features of the remaining 16 patients are summarized in Table 1. Twelve patients had gelastic seizures, 12 had focal seizures with  impaired awareness, 10 had generalized convulsions, and 2 had infantile spasms. Twelve had neurodevelopmental impairments. Three had additional structural malformations: 1 with brain anomalies, 1 with Oro-facial-digital syndrome, and 1 with Pallister Hall syndrome. Nine patients (56%) had clinical seizures without EEG correlate. The anti-seizure medications (ASM) used are summarized in Table 2. Only 1 patient was reported to be seizure free on medication; this patient was taking oxcarbazepine. Three reported relative improvement on medication: 1 on both oxcarbazepine and lacosamide, 1 on both oxcarbazepine and zonisamide, and 1 on clobazam. Eight patients had surgery for HH; 6 were resections, 1 was an ablation, and 1 was a gamma knife procedure. Of these, 5 became seizure free, 1 reported improvement in seizures, and 2 had no improvement. All patients who became seizure free underwent resective surgery.
Conclusion:
The characteristics of our HH with epilepsy population are similar to those described in the literature. Of particular clinical interest is the frequent presence of seizures without EEG correlate, high association with developmental impairments, and occasional association with other congenital anomalies. ASMs are generally ineffective in controlling these seizures. The medication with the best effect in this population was oxcarbazepine, with 1 patient achieving seizure freedom and 2 with relatively improved seizure control on this medication. By contrast, 75% of patients who underwent surgery reported improvement in seizure control, including 50% who became seizure free.
Funding:
:Funded by the CDC grant #U01DP006089