The diagnostic value of T2 map, diffusion tensor imaging, and diffusion kurtosis imaging in differentiating dermatomyositis from muscular dystrophy

Abstract

Background Dermatomyositis (DM) and muscular dystrophy are clinically difficult to differentiate. Purpose To confirm the feasibility and assess the accuracy of conventional magnetic resonance imaging (MRI), T2 map, diffusion tensor imaging (DTI), and diffusion kurtosis imaging (DKI) in the differentiation of DM from muscular dystrophy. Material and Methods Forty-two patients with DM proven by diagnostic criteria were enrolled in the study along with 23 patients with muscular dystrophy. Conventional MR, T2 map, DTI, and DKI images were obtained in the thigh musculature for all patients. Intramuscular T2 value, apparent diffusion coefficient (ADC), fractional anisotropy (FA), mean diffusivity (MD), and mean kurtosis (MK) values were compared between the patients with DM and muscular dystrophy. Student’s t-tests and receiver operating characteristic (ROC) curve analyses were performed for all parameters. P values < 0.05 were considered statistically significant. Results The intramuscular T2, ADC, FA, MD, and MK values within muscles were statistically significantly different between the DM and muscular dystrophy groups ( P<0.01). The MK value was statistically significantly different between the groups in comparison with T2 and FA value. As a supplement to conventional MRI, the parameters of MD and MK differentiated DM and muscular dystrophy may be valuable. The optimal cut-off value of ADC and MD values (with respective AUC, sensitivity, and specificity) between DM and muscular dystrophy were 1.698 ×10−3mm2/s (0.723, 54.1%, and 78.1%) and 1.80 ×10−3mm2/s (61.9% and 70.2%), respectively. Conclusion Thigh muscle ADC and MD parameters may be useful in differentiating patients with DM from those with muscular dystrophy.

Advances in The Application and Research of Magnetic Resonance Diffusion Kurtosis Imaging in The Musculoskeletal System

“…79 However, DKI is not widely used for evaluation of musculoskeletal trauma and developmental disorders, and its use is limited to spinal injury and muscular dystrophy. 39,40 Spinal injury can cause fracture and dislocation of spinal bones as well as damage to the spinal cord. This may cause mechanical damage to nerve cells, leading to impairment of the blood-brain barrier and inflammation.…”

“…Therefore, both these indices are higher in dermatomyositis in which edema is the main pathological change. 40 In the context of spinal injury, DKI can sensitively detect the influence of its lesion microstructure on water diffusion, and the diagnostic performance of MK is better. The likely reason is that MK quantifies the damage and the non-Gaussian diffusion of tissue water molecules, which can be used to assess the structural integrity of nerve cells, providing information on microstructural changes in spinal cord injury.…”

“…39,82 Musculoskeletal disorders can cause pathological changes in bones and muscles that affect the diffusion of water molecules. 40,79 However, there is a paucity of research on the use of DKI for these diseases. Therefore, we are unable to assess the DKI-based differential diagnosis of these disorders.…”

“…Musculoskeletal system developmental disorders are a group of illnesses characterized by morphological or metabolic abnormalities of the bones, joints, or skeletal muscles that are present at birth and are typically brought on by gene mutations or persistent abnormal expression of genes during embryonic development 79 . However, DKI is not widely used for evaluation of musculoskeletal trauma and developmental disorders, and its use is limited to spinal injury and muscular dystrophy 39,40 …”

Imaging More than Skin-Deep: Radiologic and Dermatologic Presentations of Systemic Disorders

“…Screening typically involves a comprehensive review of the patient’s history, physical examination, and basic labs followed by CT imaging of chest/abdomen/pelvis in cases of high suspicion. Features associated with an increased risk of malignancy include older age at onset (>45), male sex, dysphagia, cutaneous necrosis, cutaneous vasculitis, rapid onset myositis, and elevated inflammatory markers [ 8 , 9 ].…”