Diffusion tensor imaging in hyperthyroidism: assessment of microstructural white matter abnormality with a tract-based spatial statistical analysis.

BACKGROUND: Metabolic, morphological, and functional brain changes associated with a neurological deficit in hyperthyroidism have been observed. However, changes in microstructural white matter (WM), which can explain the underlying pathophysiology of brain dysfunctions, have not been researched. PURPOSE: To assess microstructural WM abnormality in patients with untreated or newly diagnosed hyperthyroidism using tract-based spatial statistics (TBSS). MATERIAL AND METHODS: Eighteen patients with hyperthyroidism and 14 age- and sex-matched healthy controls were included in this study. TBSS were used in this diffusion tensor imaging study for a whole-brain voxel-wise analysis of fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD) of WM. RESULTS: When compared to the control group, TBSS showed a significant increase in the RD of the corpus callosum, anterior and posterior corona radiata, posterior thalamic radiation, cingulum, superior longitudinal fasciculus, and the retrolenticular region of the internal capsule in patients with hyperthyroidism (P < 0.05), as well as a significant decrease in AD in the anterior corona radiata and the genu of corpus callosum (P < 0.05). CONCLUSION: This study showed that more regions are affected by the RD increase than the AD decrease in the WM tracts of patients with hyperthyroidism. These preliminary results suggest that demyelination is the main mechanism of microstructural alterations in the WM of hyperthyroid patients.

The Role of Real-Time Sonoelastography in the Differentiation of Benign From Malignant Parotid Gland Tumors.

OBJECTIVE: The aims of this study are to evaluate the utility of sonoelastography for parotid gland masses and to determine which cutoff strain ratio (SR) would be best for the differentiation between benign and malignant lesions. METHODS: From August 2015 to December 2016, 39 parotid gland masses were examined prospectively by ultrasonography and strain sonoelastography. Elastographic scores were determined by a 4-point scoring method. Interventional procedures were performed on all patients after sonographic examinations. The lesions were divided into groups as benign or malignant according to histopathological findings. The difference in elastographic scores between benign and malignant masses was evaluated. RESULTS: Among the 39 parotid gland masses, 33 (84.6%) were benign and 6 (15.3%) were malignant tumors with 53.8% (n = 21) of the lesions being on the right side. Pleomorphic adenoma (41%) was the most common neoplasm followed by Warthin tumor (28.2%). The median elastographic score was 2 (range, 1-3) for benign tumors, and it was 3 (range, 2-4) (P = 0.003) for malignant tumors. Median SR was 1.11 (range, 0.26-2.15), and it was 2.75 (range, 1.03-3.54) (P = 0.01) for benign and malignant tumors. In the receiver operating characteristic analysis, the cutoff value of the SR was 2.1, sensitivity was 83.3%, specificity was 97%, positive predictive value was 83.3%, negative predictive value was 97%, and accuracy was 94%. CONCLUSIONS: There was a statistically significant difference between benign lesions and malignant lesions in both elastography score and SR. It is possible that elastography can improve the noninvasive diagnostic accuracy for certain pathological conditions.

The correlation of the platelet-to-lymphocyte ratio with the severity of stenosis and stroke in patients with carotid arterial disease.

Objectives Platelet-to-lymphocyte ratio is a novel biomarker, recently shown to be correlated with atherosclerotic inflammation. This study investigated the role of platelet-to-lymphocyte ratio in patients with carotid artery stenosis and stroke. Methods Patients, who underwent carotid angiography with Multiple Detector Computed Tomography Angiography at our hospital, were retrospectively screened. Patients enrolled were divided into three groups based on the platelet-to-lymphocyte ratio. Patients with a platelet-to-lymphocyte ratio value between 55.0 and 106.71 were assigned to Group I, patients with a platelet-to-lymphocyte ratio value between 106.79 and 160.61 were assigned to Group II and patients with a platelet-to-lymphocyte ratio value between 162.96 and 619.61 were assigned to Group III. The carotid arterial stenosis calculated was classified as per the criteria of North American Symptomatic Carotid Endarterectomy Trial. Results One hundred fifty patients were included in our trial (mean age 61.9 ± 13.1 with 104 males). The rate of carotid arterial stenosis was detected to be higher in patients with a high platelet-to-lymphocyte ratio value (p = 0.010). Additionally, the platelet-to-lymphocyte ratio was positively correlated with the carotid arterial stenosis percentage (r = 0.250, p = 0.002). In the multi-variate regression analysis, platelet-to-lymphocyte ratio was detected to be an independent variable with respect to stroke (odd's ratio = 1.012, confidence interval = 1.001-1.024, p = 0.031). Conclusions Increased platelet-to-lymphocyte ratio could be a simple and practical marker of the clinical course in patients with carotid arterial stenosis.