An update in the MRI features, classification, and associated brain abnormalities in hypothalamic hamartomas.

Area of Science:

• Neurology
• Radiology
• Genetics

Background:

• Hypothalamic hamartomas (HHs) are rare malformations linked to gelastic seizures and precocious puberty.
• Recent classifications suggest HH subtypes correlate with clinical features and may co-occur with other brain anomalies.

Purpose of the Study:

• To investigate the imaging features of HH.
• To determine the prevalence of concurrent structural abnormalities.
• To assess metabolic alterations using magnetic resonance spectroscopy (MRS).

Main Methods:

• Retrospective analysis of MRI and MRS data from 18 HH patients.
• Classification of HH lesions based on morphology, signal characteristics, and associated abnormalities.
• Measurement of choline-to-N-acetylaspartate (Cho/NAA) ratios via MRS.

Main Results:

• Gelastic seizures were present in 77.8% of patients; 4 patients had non-seizure-related HH, including precocious puberty and NF1.
• Concurrent brain abnormalities were identified in 50% of cases, such as focal cortical dysplasia and corpus callosum hypoplasia.
• MRS analysis in 3 patients indicated elevated Cho/NAA ratios.

Conclusions:

• HH is frequently associated with structural abnormalities and metabolic alterations, particularly in seizure-related cases.
• Findings support a broader spectrum of HH-related brain abnormalities, necessitating further investigation.
• Elevated Cho/NAA ratios may serve as a potential biomarker for HH.