Spinal cord magnetic resonance imaging demonstrates sensory neuronal involvement and clinical severity in neuronopathy associated with Sjögren's syndrome

OBJECTIVES To determine spinal cord MRI findings in neuronopathy associated with Sjögren's syndrome and their correlation with severity of sensory impairment. METHODS Clinical and electrophysiological features, pathological findings in the sural nerve, and hyperintensity on T2* weighted MRI in the spinal dorsal columns were evaluated in 14 patients with neuronopathy associated with Sjögren's syndrome. RESULTS Of 14 patients, 12 showed high intensity by T2* weighted MRI in the posterior columns of the cervical cord. High intensity areas were seen in both the fasciculus cuneatus and gracilis in nine patients, who showed severe and widespread sensory deficits in the limbs and trunk; these patients also had a high frequency of autonomic symptoms. Somatosensory evoked potentials often could not be elicited. Hyperintensity restricted to the fasciculus gracilis was seen in three patients, who showed sensory deficits restricted to lower limbs without trunk involvement, or with only partial limb involvement; no autonomic symptoms were noted. The two patients who did not show high intensity areas in the dorsal columns showed restricted sensory involvement in the limbs. All patients showed axonal loss predominantly affecting large fibres, without axonal sprouting. CONCLUSIONS High intensity areas on T2* weighted MRI in the spinal dorsal columns reflect the degree of sensory neuronal involvement in neuronopathy associated with Sjögren's syndrome; this finding could also be a helpful marker for estimating severity of this neuronopathy.