Calvarial melorheostosis: an extremely rare case and diagnostic challenge

TL;DR

This paper reports a rare case of melorheostosis in the skull, highlighting its unusual presentation and diagnostic challenges.

Contribution

The novelty lies in presenting an extremely rare calvarial case of melorheostosis with imaging and pathology insights.

Findings

Melorheostosis was diagnosed in the calvarium of a 55-year-old male, a rare location for this disease.

Molecular studies suggest genetic mutations may be involved in the disease's pathogenesis.

Abstract

Melorheostosis is a rare bone disease that presents as sclerotic lesions growing on existing bone surfaces. This disease is of unknown etiology and affects both genders equally. The disease is unique in appearance, described in the literature as having a radiologic appearance of flowing candle wax, and usually occurs in the appendicular skeleton. We present an extremely rare case of melorheostosis of the calvarium in a 55-year-old male patient, initially thought to represent a large osteoma, and discuss the CT and MRI features, pathology, and surgical management. Recently, new insights have been gained by molecular biologic studies into the potential pathogenesis of this disease indicating genetic mutations, which will be discussed. This case report will help radiologists arriving at the correct diagnosis for an unusual manifestation of a rare disease.

The online version contains supplementary material available at 10.1007/s00256-025-04882-w.

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