Forty splenic infarcts in 23 patients were examined with ultrasound (US). At clinical presentation, splenic infarction was associated with severe left upper quadrant pain (n = 10) or diffuse abdominal pain (n = 4) or was asymptomatic (n = 9). In this retrospective study, predominantly wedge-shaped (n = 17) or round (n = 23), irregularly delineated (n = 33) or smooth (n = 7), hypoechoic (n = 40) and anechoic (n = 5) lesions were found at first examination. During follow-up observation, four patients died because of complications unrelated to infarct, and five patients underwent splenectomy as a consequence of US findings. Expanding intralienal liquefaction, increasing subcapsular hemorrhage, free peritoneal blood (even in spleens shown to have an intact surface at sonography), and flow phenomena in the area of infarction demonstrated at B-mode pulsed Doppler US were identified as infarct-related complications associated with the risk of splenic rupture. Despite the high self-healing tendency in splenic infarction, short-term follow-up with US is recommended for early recognition of these possible complications.