Fig. 1From: “Sponge pattern” of the spleen: a rarely described high-frequency ultrasound pattern in HIV-positive patientsSonographic appearance of the spleen of index patient. a Numerous tiny hypoechoic areas (arrows) are seen throughout the splenic tissue. b The areas measure about 2 mm in diameter (Block arrows: 1: 1.9 mm, 2: 2.0 mm, 3: 2.4 mm). c In some still views a more linear appearance is noted which is better visible in the moving scan (see Additional file 1: Video clip S1a). d Using the power mode it can be seen that some of the structures follow the vasculature (see Additional file 2: Video clip S1b); others seem isolatedBack to article page