[Tarsal tunnel syndrome. MRI diagnosis].

Clinical findings and symptoms of tarsal tunnel are commonly vague and diffuse and electrodiagnostic studies do not provide definitive diagnosis. MR imaging with its excellent soft tissue contrast can demonstrate clearly the anatomy of the tarsal tunnel and its contents. MRI is able to demonstrate a space-occupying lesion and its relationship to the posterior tibial nerve and its branches. This information aids in surgical planning by determining the extent of the decompression required. MR imaging may also be used to follow up non-surgical causes of tarsal tunnel syndrome such as tenosynovitis.