Cystic splenic lesions: a sonographic approach-retrospective study in 111 patients

To describe and categorize splenic cystic-appearing lesions (S-CAL) with B-mode and contrast-enhanced ultrasound (CEUS).

This retrospective study investigated S-CALs in 111 patients between 2003 and 2023 in an interdisciplinary ultrasound center with B-mode ultrasound, color Doppler sonography (CDS), and CEUS. S-CAL was characterized by echogenicity, diameter, and shape, as well as additional features like septation, calcification, or wall thickening, and CDS/CEUS were used to identify perfusion. Histological examination or imaging follow-up was necessary to determine the nature of S-CAL. Moreover, 'S-CAL with risk' was defined, necessitating further procedures. Four types (0-III) of S-CALs were defined based on ultrasound parameters. Fisher's exact test was used to compare non-parametric data.

S-CAL of 111 patients (58 female, 53 men-average age: 58.6 years) was examined. Final diagnoses were: splenic cyst (n = 64, 57.7%); splenic abscess (n = 10, 9.0%); intrasplenic pseudoaneurysm (n = 10, 9.0%); splenic metastasis (n = 10, 9.0%); splenic infarction (n = 6, 5.4%); splenic hematoma (n = 4, 3.6%); other (n = 7, 6.3%). S-CAL groupings were type 0 (n = 11, 9.9%), type I (n = 33, 29.7%), type II (n = 24, 21.6%), and type III (n = 43, 38.7%). 'S-CAL with risk' was diagnosed in n = 41 (36.9%). Malignant S-CAL was only seen in type II (n = 2, 8.2%) and type III (n = 9, 20.9%) (p < 0.001). 'S-CALs with risk' were found more frequently in type 0 (n = 11, 100%), type II (n = 16, 66.7%) and type III (n = 13, 30.2%) than in type I (n = 1, 3%) (p < 0.001).

B-mode ultrasound, CDS, and CEUS are useful to further characterize and follow-up S-CAL and identify 'S-CAL with risk', requiring further procedures.

Ultrasound imaging is valuable for the detection, categorization, and monitoring of cystic-appearing lesions of the spleen, as well as for the identification of those with risk.

An S-CAL may introduce uncertainty in clinical practice as imaging-based risk stratification is missing. B-mode and CEUS, along with the clinical context and follow-up, assist in characterizing and identifying 'S-CAL with risk'. S-CALs encompass various lesions, including simple cysts, metastases, abscesses, and intrasplenic pseudoaneurysms.