Baseline and Evolutionary Radiologic Features in Sporadic, Hemorrhagic Brain Cavernous Malformations

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Cavernous malformations (CMs) are vascular brain lesions.
• While initial imaging features are known, their natural history, especially after hemorrhage, is less understood.

Purpose of the Study:

• To describe the typical evolution of sporadic, hemorrhagic brain cavernous malformations over time using serial MRI.

Main Methods:

• Retrospective analysis of 51 patients with sporadic, hemorrhagic brain CMs from an institutional registry.
• Assessment of initial and follow-up brain MRI features, including lesion type, T1 hyperintensity, edema, and diffusion-weighted imaging (DWI) intensity.

Main Results:

• Initial lesions were predominantly Zabramski type I with T1 hyperintensity and edema.
• 15.6% of patients rebled within the first year, showing new T1 hyperintensity, edema, and growth.
• Lesion types shifted from type I to II/III by 90 days; edema resolved unless rebleeding occurred.
• T1 hyperintensity and DWI hypointensity changed characteristically over time post-hemorrhage.

Conclusions:

• Hemorrhagic brain cavernous malformations exhibit a distinct evolutionary pattern on serial MRI.
• Knowledge of this evolution aids in interpreting imaging findings, distinguishing CMs from mimics, and guiding follow-up imaging schedules.