Abstract
BACKGROUND AND PURPOSE: DTI is widely used for the evaluation of white matter integrity in various neurologic diseases. The purpose of this study was to investigate changes in white matter integrity by using DTI in NAWM of patients with MMD and to evaluate the correlation between diffusion and perfusion characteristics through an interhemispheric comparison.
MATERIALS AND METHODS: We retrospectively reviewed 20 primary MMD patients with asymmetric disease stage and 20 age-matched healthy controls. FACS and ADCCS values of bilateral centrum semiovale were measured by using region of interest analysis. Mean FACS and ADCCS were compared between patient and control groups by unpaired t test. Interhemispheric differences in FACS and ADCCS were assessed and compared between the H-TTPdelayed and the H-TTPshorter by using paired t test. AIs also were assessed to verify interhemispheric differences.
RESULTS: The patient group showed a significantly lower mean FACS and a higher mean ADCCS value than the control group. In the patient group, the H-TTPdelayed had a significantly lower FACS and higher ADCCS value than the H-TTPshorter. Both AIFA and AIADC were significantly higher in the patient compared with the control group.
CONCLUSIONS: DTI can describe subtle changes in white matter integrity in NAWM of patients with primary MMD that are not detected by conventional MR imaging. In addition, diffusion characteristics are well correlated with perfusion characteristics. We believe that DTI is a useful ancillary tool to evaluate patients with MMD.
Abbreviations
- ADCCS
- apparent diffusion coefficient in centrum semiovale
- AI
- asymmetric index
- FACS
- fractional anisotropy in centrum semiovale
- H-TTPdelayed
- hemisphere with more delayed time-to-peak
- H-TTPshorter
- contralateral hemisphere of H-TTPdelayed
- MMD
- Moyamoya disease
- NAWM
- normal-appearing white matter
- PWI
- perfusion-weighted MR imaging
- rCBV
- relative cerebral blood volume
- © 2011 by American Journal of Neuroradiology