Case 4 :

6 year old male presents with history of dropping objects from his right hand. Clinical examination revealed mild weakness of both upper and lower limbs and wasting of the hypothenar eminences of the hand. No sensory deficit was noted.

MRI of the spine was performed. What is the diagnosis?

neuro_4_contrast.jpg (3937 bytes) neuro_4_flexion.jpg (2897 bytes) neuro_4_t1wi.jpg (3483 bytes)
Contrast Flexion T1WI

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Os odontoideum and ependymoma.



Plain x-rays of the cervical spine were suggestive of atlanto-axial dislocation. Sagittal T1WI revealed a hypoplastic ossicle of the dens separate from the body of C2. Spinal cord revealed multiple, small CSF intensity areas extending from the cervico-medullary junction to C3. Although these were initially suggestive of syringomyelia/ myelomalacia, contrast scan showed intense homogenous enhancement, indicative of an intra medullary tumor.

A single step operation was performed for cranio-cervical instability and excision of the intra medullary tumor, histopathological examination revealed an astrocytoma.

Etiology of os odontoideum is controversial; some attribute it to a congenital condition while some believe it is due to trauma. Spinal cord astrocytomas are also not rare in children. However, the association of these two conditions is rare.



Dr. Deepak Patkar, MRI Nanavati, Mumbai.