Emerging and established biomarkers of oculopharyngeal muscular dystrophy.

Oculopharyngeal muscular dystrophy (OPMD) is a rare, primarily autosomal dominant, late onset muscular dystrophy commonly presenting with ptosis, dysphagia, and subsequent weakness of proximal muscles. Although OPMD diagnosis can be confirmed with high confidence by genetic testing, the slow progression of OPMD poses a significant challenge to clinical monitoring and a barrier to assessing the efficacy of treatments during clinical trials. Accordingly, there is a pressing need for more sensitive measures of OPMD progression, particularly those which do not require a muscle biopsy. This review provides an overview of progress in OPMD biomarkers from clinical assessment, quantitative imaging, histological assessments, and genomics, as well as hypothesis-generating "omics" approaches. The ongoing search for biomarkers relevant to OPMD progression needs an integrative, longitudinal approach combining validated and experimental approaches which may include clinical, imaging, demographic, and biochemical assessment methods. A multi-omics approach to biochemical biomarker discovery could help provide context for differences found between individuals with varying levels of disease activity and provide insight into pathomechanisms and prognosis of OPMD.

Quantitative vs qualitative muscle MRI: Imaging biomarker in patients with Oculopharyngeal Muscular Dystrophy (OPMD).

Oculopharyngeal muscular dystrophy (OPMD) is a genetic muscle disease causing ptosis, severe swallowing difficulties and progressive limb weakness, although atypical presentations may be difficult to diagnose. Sensitive biomarkers of disease progression in OPMD are needed to enable more effective clinical trials. This study was designed to test the feasibility of using MRI to aid OPMD diagnosis and monitor OPMD progression. Twenty-five subjects with Dixon whole-body muscle MRI were enrolled: 10 patients with genetically confirmed OPMD, 10 patients with non-OPMD muscular dystrophies, and 5 controls. Using the MRI Dixon technique, muscle fat replacement was evaluated in the tongue, serratus anterior, lumbar paraspinal, adductor magnus, and soleus muscles using quantitative and semi-quantitative rating methods. Changes were compared with muscle strength testing, dysphagia severity, use of gait aids, and presence of dysarthria. Quantitative MRI scores of muscle fat replacement in the tongue could differentiate OPMD from other muscular dystrophies and from controls. Moreover, fat fraction in the tongue correlated with clinical severity of dysphagia. This study provides preliminary support for the use of Dixon-based quantitative MRI images as outcome measures for monitoring disease progression in clinical trials and provides rationale for future prospective studies aimed at methodological refinement and covariate identification.

Patellar maltracking: an update on the diagnosis and treatment strategies.

Patellar maltracking occurs as a result of an imbalance in the dynamic relationship between the patella and trochlea. This is often secondary to an underlying structural abnormality. The clinical evaluation can provide useful clues for the presence of such entity; however, the diagnosis can often be challenging especially in the absence of a documented history of patellar dislocation. Imaging, particularly MRI, can detect subtle features that could lead to the diagnosis, probably even more importantly when there is no clear history of patellar dislocation or before its development. This can provide a road map for formulating a treatment strategy that would be primarily aimed at stabilizing the patellofemoral joint to halt or slow the progression of articular cartilage loss. The purpose of this article is to discuss the clinical and radiologic evaluation of patellar maltracking providing an update on the cross-sectional imaging assessment and also a synopsis of the management options.

Breast cancer and bone metastases: the association of axial skeleton MRI findings with skeletal-related events and survival.

The purpose of this study was to determine if bone metastasis characteristics on axial skeleton MRI are associated with either skeletal-related events (SREs) or survival in breast cancer patients. A retrospective review was performed on 247 breast cancer patients with bone metastases identified on axial skeleton MRI. MRI studies were reviewed for metastases T1 signal, signal uniformity, complete vertebral metastatic marrow replacement, metastases quantity, and distribution. Odds ratio (OR) and hazard ratios (HR) were calculated, with 95 % confidence intervals (95 % CI), to determine association with either future SREs or survival. At the time of analysis, 174 (70 %) patients had developed SREs and 176 (71 %) patients were dead. Features of skeletal metastases associated with SREs included the presence of complete metastatic marrow replacement within any vertebra; OR 2.363 (95 % CI 1.240-4.504, P = 0.0090), and more widely distributed metastases; OR 1.239 (95 % CI 1.070-1.435, P = 0.0040). Features associated with shorter survival included the presence of complete metastatic marrow replacement within any vertebra; HR 1.500 (95 % CI 1.105-2.036, P = 0.0093), and more widely distributed metastases; HR 1.141 (95 % CI 1.047-1.243, P = 0.0027). Metastases T1 signal, signal uniformity, and surprisingly quantity were not associated with SREs or survival. Axial skeleton MRI was able to identify characteristics predictive of future SREs and survival. These characteristics could be used for risk stratification for future trials if prospectively validated.