R. Shah

SUMMARY: We report DTI and fiber tractography findings in a case of hypertrophic olivary degeneration. A 51-year-old man presented with an abnormal gait and visual difficulties. MR imaging showed enlargement of the right medullary olive and a vascular lesion in the right pontine tegmentum. Fiber tractography showed decreased volume of the right central tegmental tract, supporting a diagnosis of HOD.

BACKGROUND AND PURPOSE: MR imaging is widely used for the diagnosis and follow-up of neurosarcoidosis lesions. However, the temporal evolution of imaging abnormalities and the prognostic significance of imaging features is not well understood. We undertook a retrospective study of patients with biopsy-proved or clinically diagnosed neurosarcoidosis for the following reasons: 1) to assess concordance between abnormalities noted on MR imaging with neurologic symptoms at presentation; 2) to correlate changes in imaging findings during follow-up with clinical improvement or worsening; and 3) to identify imaging features that may have prognostic significance. MATERIALS AND METHODS: We reviewed radiologic records from 1999 to 2008 of patients with biopsy-proved or clinically diagnosed neurosarcoidosis and correlated MR imaging findings in these patients with their demographic characteristics, clinical features, and symptomatic responses during follow-up. RESULTS: Thirty-two patients were included in the study. Cranial nerve lesions and leptomeningeal disease identified on MR imaging were symptomatic in 64% patients, dural lesions were associated with symptoms in 28% patients, but nonenhancing white matter lesions did not have correlating symptoms. During follow-up, MR imaging findings generally changed in concordance with the change in clinical symptoms (80% patients). Cranial nerve enhancement (9/11) and spinal lesions (5/8) were most likely to resolve with clinical improvement, whereas dural lesions (6/11), enhancing parenchymal lesions (3/7), and non-enhancing parenchymal lesions (0/4) were less likely to change during therapy. Patients with ≥1 enhancing T2-hypointense lesion (4/7, 57%) were less likely to show clinical improvement than those without such lesions (12/13, 92%). CONCLUSIONS: Although many sarcoid-related MR imaging abnormalities were not associated with correlating symptoms at presentation, there was a high degree of concordance between changes in clinical symptoms and MR imaging abnormalities during follow-up. Enhancing T2-hypointense dural and parenchymal lesions were associated with suboptimal imaging and clinical response to immunosuppressive therapy.