Magnetic Resonance Imaging of Cerebral Aspergillosis: Imaging and Pathological Correlations

Area of Science:

• Neurology
• Infectious Diseases
• Radiology

Background:

• Cerebral aspergillosis significantly impacts patient morbidity and mortality.
• Imaging characteristics of cerebral aspergillosis lesions lack a definitive consensus.
• Understanding lesion patterns is crucial for diagnosis and treatment.

Purpose of the Study:

• To review and characterize Magnetic Resonance Imaging (MRI) findings in cerebral aspergillosis.
• To correlate imaging findings with patient immune status and neuropathological data.
• To differentiate imaging patterns based on the route of fungal dissemination.

Main Methods:

• Retrospective review of MRI findings in 21 patients diagnosed with cerebral aspergillosis.
• Correlation of imaging features (lesion number, topography, signal intensity) with patient immune status.
• Analysis of neuropathological findings when available.
• Categorization of dissemination routes: direct spread from paranasal sinuses vs. hematogenous spread.

Main Results:

• Hematogenous dissemination (13 patients, all immunosuppressed) showed numerous parenchymal abscesses (329 total) with corticomedullary junction predilection and corpus callosum involvement.
• Direct spread from paranasal sinuses (8 patients, 6 immunocompetent) presented different lesion characteristics.
• Hemorrhagic lesions occurred in 13%, contrast enhancement in 61%.
• Hematogenous spread was linked to younger patients, more intracranial lesions, and higher 12-week mortality.
• Aneurysm characteristics differed: saccular and proximal in direct spread, distal and fusiform in hematogenous spread.

Conclusions:

• MRI is the preferred imaging modality for diagnosing cerebral aspergillosis.
• The number and type of cerebral lesions vary significantly based on the dissemination route (direct sinus spread vs. hematogenous).
• Immune status critically influences the pattern and outcomes of cerebral aspergillosis.