Echogenicity of benign adrenal focal lesions on imaging with new ultrasound techniques - report with pictorial presentation.

AIM: The aim of the research was to assess the echogenicity of benign adrenal focal lesions using new ultrasound techniques.

MATERIAL AND METHOD: 34 benign adrenal masses in 29 patients were analyzed retrospectively. The examinations were conducted using Aplio XG (Toshiba, Japan) ultrasound scanner with a convex probe 1-6 MHz in the B-mode presentation with the combined use of new ultrasound techniques: harmonic imaging and spatial compound sonography. The size of the adrenal tumors, their echogenicity and homogeneity were analyzed. Statistical analysis was conducted using the STATISTICA 10 software.

RESULTS: The following adrenal masses were assessed: 12 adenomas, 10 nodular hyperplasias of adrenal cortex, 7 myelolipomas, 3 pheochromocytomas, a hemangioma with hemorrhage and a cyst. The mean diameter of nodular hyperplasia of adrenal cortex was not statistically different from that of adenomas (p = 0.075). The possibility of differentiating between nodular hyperplasia and adenoma using the parameter of hypoechogenicity or homogeneity of the lesion was demonstrated with the sensitivity and specificity of 100% and 41.7%, respectively. The larger the benign adrenal tumor was, the more frequently did it turn out to have a mixed and inhomogenous echogenicity (p < 0.05; ROC areas under the curve: 0.832 and 0.805, respectively).

CONCLUSIONS: A variety of echogenicity patterns of benign adrenal focal lesions was demonstrated. The image of an adrenal tumor correlates with its size. The ultrasound examination, apart from its indisputable usefulness in detecting and monitoring adrenal tumors, may also allow for the differentiation between benign lesions. However, for lesions found incidentally an algorithm for the assessment of adrenal incidentalomas is applicable, which includes computed tomography and magnetic resonance imaging.