There is no specific role for MRI in diagnosis of HIT. However, MRI can be useful to help delineate a bleeding or thrombotic complication of HIT in a specific anatomical area, similar to the role of a CT scan. MRI offers better anatomical detail and is thus more sensitive that CT scan. However, the test is more expensive, so one must weigh the cost-benefit ratio. MRI is particularly useful for suspected dural venous sinus thrombosis.

There is no specific role for MRI in diagnosis of HIT. However, MRI of a particular anatomic area can help better delineate thrombosis or bleeding if a CT with contrast (CT angiography) cannot be performed. For example, if a patient has renal dysfunction that precludes use of iodinated contrast with CT scan, MRI may be useful.

• MRI brain with venography: This can help diagnose a cerebral venous thrombosis. MRI is the gold standard test for diagnosis of cerebral venous thrombosis or dural venous sinus thrombosis.^[1] CT scan will not reveal a thrombosis with as great anatomical detail.
• MRI abdomen or pelvis: This can help reveal intra-abdominal or intrapelvic bleeding or thrombosis. However, a CT scan is able to reveal these conditions at a much lower cost.
• MRI of the extremities: MRI is particularly useful for delineating soft tissue abnormalities, such as bleeding into musculature or nerves.