Contrast-enhanced sonography for differential diagnosis of an inhomogeneous spleen of unknown cause in patients with pain in the left upper quadrant.

OBJECTIVE: Second-generation contrast agents have shown spleen-specific uptake. The aim of this study was to investigate the ability of contrast-enhanced sonography (CES) to demarcate splenic lesions in patients with pain in the left upper quadrant (LUQ) and an inhomogeneous splenic texture.

METHODS: From October 2003 to July 2005, 31 consecutive patients with pain in the LUQ and splenic inhomogeneity on B-mode sonography were studied by CES using a second-generation contrast agent (SonoVue; Bracco SpA, Milan, Italy). The following data were retrospectively evaluated: extent of enhancement (EE) of the spleen and focal splenic lesions was determined and classified, with the EE of surrounding tissue used as an in vivo reference. Focal splenic lesions were classified after CES as round or wedge shaped, solitary or multiple, and anechoic, hypoechoic, or hyperechoic.

RESULTS: The EE of the spleen after CES was anechoic (n = 1), hypoechoic (n = 1), or hyperechoic (n = 29). In 16 of 31 patients, focal lesions were seen after CES. The EE of the lesions was anechoic (n = 11) or hypoechoic (n = 5). Lesions were solitary (n = 6) or multiple (n = 10) and round (n = 5) or wedge shaped (n = 11). Final clinical diagnoses of splenic abnormalities were no specific diagnosis (n = 13), complete autosplenectomy (n = 2), splenic lymphoma (n = 5), and splenic infarction (n = 11). The CES diagnoses were confirmed by computed tomography (n = 21), scintigraphy (n = 2), magnetic resonance imaging (n = 1), and clinical follow-up (n = 7).

CONCLUSIONS: In patients with pain in the LUQ and splenic inhomogeneity, CES enables visualization of splenic abnormalities in more than 50% of the patients; in this group, splenic infarction was the most common diagnosis.