To enumerate the differential diagnosis of intramedullary pathologies which present as atypical myelopathy. To describe the pattern approach of intramedullary lesions. To describe the MRI findings and approach of the different types of intramedullary spinal cord pathologies in a case-based approach.

A wide spectrum of intradural intramedullary pathologies presents clinically as neurological deficits mimicking spondylotic myelopathies. MRI is the investigation of choice to evaluate such pathologies. We enlist various intramedullary lesions with their MRI features and an approach to such lesions based on age, location, and advanced imaging findings. We emphasize rare pathologies.

1500 patients who underwent magnetic resonance imaging of the spine from 2012-2018 were included in the analysis. The following pathologies which presented as atypical myelopathy were encountered on MRI analysis: •Glial neoplasms - Ependymoma, Astrocytoma. •Mixed neuronal/ glial neoplasm - Ganglioglioma. •Non-glial neoplasm: Vascular neoplasms – Haemangioblastoma, Paraganglioma. •Rare non-glial neoplasm- Lymphoma, Metastasis. •Benign neoplasms – Epidermoid, Lipoma. •Infective masses – Tuberculous granuloma, Hydatid disease. •Vascular masses – Arteriovenous malformation and cavernoma. •Others – Transverse myelitis, Multiple Sclerosis, Hirayama disease. Need for MRI pattern approach?...

We illustrate broad differential diagnosis for intramedullary spinal cord lesions presenting as atypical myelopathy and their characteristic imaging features on magnetic resonance imaging and approach based on demographics along with imaging findings which are important for timely diagnosis and intervention for appropriate management and prevention of morbidity for the better social and economic life of the patient.

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