Ultrasound evaluation of parathyroid glands pathology in patients with chronic renal failure treated by dialysis

Localization and anatomical patterns of enlarged parathyroid glands is very significant for diagnostics and treatment of dialysis patients suffering with secondary hyperparathyroidism. The assessment included 76 dialysis patients with chronic renal failure. The dialysis duration ranged from 0.5 months to 15 years. Parathyroid gland hyperplasia was found among 39 (51.3%) of the patients. The size of parathyroid glands varied from 0.4cm through 3.4cm; the volume – from 0.02 through 6.1cm³. In all cases echogenicity of detected parathyroid glands was lower than that of thyroid gland tissue. In 38.1% of cases structure of parathyroid glands was moderately or severely nonhomogeneous because of fine areas of increased echogenicity, calcifications and unechogenic inclusions. Retrospective analysis of the ultrasound picture of the enlarged parathyroid gland of patients who underwent parathyroidectomy, suggests the presence of parathyroid adenoma, when clearly defined capsule is detected, with tumor shape close to circle or oval, and size of more than 8mm. The direct correlation of moderate degree was detected between the size of a gland and the rate of systolic blood flow in the main artery (τ=0.344), and arteries inside glands tissue (τ=0.451). Comparison of blood flow rates in parathyroid glands tissue reliably revealed higher speed in cases of adenoma (p<0.05), rather than in cases of hyperplasia. Therefore, regular ultrasound exams allow timely detection of changes in parathyroid gland, to evaluate degree of hyperplasia, probability of benign tumor development, and to provide adequate therapy of secondary hyperparathyroidism.