Role of ultrasonography and computed tomography in the evaluation of focal splenic lesions

Abstract

OBJECTIVE: To study the role of ultrasonography and computed tomography in the evaluation of focal splenic lesions, to compare their diagnostic accuracies, to study the differential diagnosis of focal splenic lesions, to evaluate the imaging features of common lesions and to calculate the incidence of focal splenic involvement in lymphomas. MATERIALS AND METHODS: A prospective study of 46 patients was undertaken in whom focal lesions in the spleen were detected on USG, CT or both. In all patients, USG was done and images were stored. Five mm thick contiguous sections were obtained from the spleen before and after injection of intravenous contrast material in the portovenous phase. RESULTS: Of the focal splenic lesions 28 (60.8%) were benign and 18 (39.2%) were malignant. The spectrum of benign lesions included cysts (4), infarcts (10), abscesses (9) HIV+ve cases with focal hypodense splenic lesions (5) and a case of inflammatory pseudotumour. Malignant lesions included 6 cases each of Hodgkin′s and non-Hodgkin′s lymphoma and 6 cases of metastatic deposits in the spleen. Diagnostic accuracy of plain CT was 78.7%, of USG 87.2% and of CECT was 100%. Lesion detection was significantly improved by contrast enhancement. NHL, especially the high grade lymphomas presented with large nodular pattern of involvement of spleen whereas Hodgkin′s lymphoma presented in majority of cases with small nodular pattern of involvement. Imaging features of infarcts corresponded to the classic wedge shaped peripheral pattern in a majority,(80%) and were extensive with hilar sparing in 20%. CONCLUSION: We concluded that contrast enhanced CT is the ideal modality for detection of focal splenic lesions, with USG being used mainly for follow up. The spectrum of differentials of focal splenic lesions in our study corresponded with reports in literature.

Keywords

• CT
• USG
• focal splenic lesions.