MRI change metrics of facioscapulohumeral muscular dystrophy: STIR and T1

See MRI change metrics of facioscapulohumeral muscular dystrophy: STIR and T1

INTRODUCTION:

MRI evaluation in facioscapulohumeral muscular dystrophy (FSHD) demonstrates fatty replacement and inflammation/edema in muscle. Our previous work demonstrated Short T1 Inversion Recovery (STIR)-hyperintense (STIR+) signal in muscle 2 years prior to fatty replacement. We evaluated leg muscle STIR changes and fatty replacement within 14 months.

METHODS:

FSHD subjects received 2 MRI scans of thigh and calf over a 6.9-13.8 month interval. Quality of life measures were collected. One radiologist rated muscle changes on a semi-quantitative scale.

RESULTS:

Fifteen subjects completed longitudinal imaging. Four STIR+ muscles and 3 STIR-normal (STIR-) muscles were rated as progressing to fatty tissue over the study period.

DISCUSSION:

STIR+ muscles with confluent regions of fat at baseline increased more in fat, while STIR- muscles had increases in septal-fat over the study period. These changes may reflect two phases of FSHD, demonstrating MRI sensitivity is weighted towards gross pathological phases of the disease. This article is protected by copyright. All rights reserved.

See grant Longitudinal Progression of Edema and Fatty Replacement of Lower Extremity Muscles in FSHD