The kidneys are primarily evaluated to rule out hydronephrosis in patients with renal colic. Severe hydronephrosis may distort the appearance of the kidney. The kidney may be obstructed without hydronephrosis. Blunt or penetrating trauma Ultrasonography can aid in localizing the source of life-threatening hypotension. Fluid may accumulate in a number of anatomic spaces in the abdomen, including the pelvic, subphrenic, subhepatic, paracolic gutter, perinephric, and pleural spaces.
Free fluid appears anechoic or dark without echos.
Clotted blood has a particulate, hypoechoic appearance. Appendicitis The normal appendix is rarely seen. The wall of the appendix usually is no more than 6 mm thick. The normal appendix compresses when pressure is applied with the transducer. In acute appendicitis, wall thickness is 7 mm or more, and the appendix is noncompressible.