Miliary cerebral metastases: prevalence and radiological findings

Abstract

Aims: Miliary cerebral metastases, also known as carcinomatosis encephalitis, represent an unusual form of metastatic disease in the brain. Due to their rarity, limited literature is available, restricting our understanding of this condition. This study aimed to evaluate the prevalence and imaging characteristics of miliary cerebral metastases in a cohort of metastatic patients. Methods: A retrospective review was conducted on approximately 618 contrast-enhanced MRI scans from patients with metastatic disease who had not undergone surgical intervention or received radiotherapy. Cases of miliary cerebral metastases were identified and analyzed. Demographic data, primary cancer types, non-contrast CT and MRI findings of miliary metastasis cases were evaluated. Results: Miliary cerebral metastases were identified in 6 out of the 618 metastatic patients included in the study. The radiological features included small, disseminated hyperintense lesions visible on post-contrast T1-weighted images. These lesions were diffusely scattered throughout the brain, predominantly at the grey-white matter junction. Conclusion: Our findings highlight the rarity of miliary cerebral metastases, supporting the limited cases reported in the literature. These findings underscore the need for increased clinical awareness and further research into this condition. High-resolution, contrast-enhanced MRI plays a vital role in detecting and characterizing miliary cerebral metastases, aiding in their management.

Keywords

• Miliary cerebral metastases
• carcinomatosis encephalitis
• metastatic disease
• MRI
• brain metastases

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