Case 3 :
A 30 year old male patient presented with history of acute onset backache, pain radiating along both lower limbs and retention of urine. There was no history of fever or trauma. Plain x-rays of the lumbar spine were normal. click here for bigger picture

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MRI Findings

There was focal expansion of the spinal cord at D12/L1 vertebral level (pic 1). T2 weighted images revealed a heterogenous hypointense lesion at this level (pic 2). It appeared isointense on T1WI. These findings were consistent with acute hemorrhage (deoxyhaemoglobin). No enhancement was noted after intravenous administration of Gadolinium-DTPA.

Diagnosis :

Vascular malformation of the spinal cord.

Brief Discussion :

Vascular malformations of the spine and spinal cord are uncommon lesions accounting for 3-11% of spinal space occupying lesions. Most are arterio-venous malformations (AVM's) or arterio-venous fistulae.Cavernous angiomas and capillary telegictasias are less common. Venous angiomas are rare. Pathologically, AVM's have a true nidus of pathological vessels interposed between enlarged feeding arteries and draining veins. AVM's are of four types:
Type I : Commonest, is a dural AVF found in the dorsal aspect of the lower thoracic cord and conus medullaris, typically affects men between their fifth and eighth decades.
Type II : AVMs are intramedullary, located dorsally in the cervico-medullary region, mostly occuring in younger men.
Type III : Juvenile AVMs are intra medullary, and often have extra medullary / extraspinal extension.
Type IV : are intra dural / extra medullary AVFs and usually lie anterior to the spinal cord near the conus medullaris.

The commonest clinical presentations are paresis, sensory changes, bowel/ bladder dysfunction, and impotence. Haemorrhage is seen in approximately 50% of cases.

Contribution : Dr. Deepak Patkar, MRI Scan Centre, Nanavati Hospital, Mumbai.