A Rare Retroclival Intradural Lesion: Ecchordosis Physaliphora

Ecchordosis Physaliphora is a rare benign lesion derived from the notochord remnants. It can be found anywhere from skull base to sacrum in midline. Most commonly it is located in the retroclival prepontine region. It could be confused with the differentials of chordoma, skull base metastases, neuroenteric cysts, epidermoid cyst and arachnoid cyst. Hence, knowledge about this rare entity is important to differentiate it from other differentials.