Imaging diagnostics of renal trauma.

The aim of the study is presenting the diagnostic value of different imaging modalities in the evaluation of patients with renal injury. The material comprises a group of 16 patients with blunt abdominal trauma. Six of them were treated surgically. Plain abdominal radiography was performed in 9 patients, urography in 7, US examination in 16 patients and CT in 12 cases. The renal injuries in US were found in 16 cases, 7 of them were isolated and in 9 patients multi-organ injuries were found, with liver injury in 2 of them. The minor injuries were found in 8 cases. In other 8 cases severe renal injuries were found. The perirenal haematomas were visible as non-enhancing areas adjacent to kidney. The parenchymal laceration appeared as linear non-enhancing areas in the renal parenchyma. In the group of minor renal lesion in 3 cases the renal contusion was found and small parenchymal and subcapsular haematomas in 2 cases appearing as hyperdense subcapsular areas, without evident contrast enhancement. In 2 cases CT revealed perirenal extravasations of blood, appearing as perirenal masses (density of 50 HU), and not revealing contrast enhancement. In 2 cases in CT retroperitoneal haematomas were found. The absence of excretion was found in 2 cases, representing severe injury of the renal pedicle. In 3 cases the injury of ureteropelvic system with extravasations of the contrasted urine into perinephric area was found in CT and in urography. That was the most frequent urographic sign of renal laceration. In 3 cases axial sections revealed injuries of renal collecting system, with subtle extravasation of contrasted urine. In 2 other cases of extensive parenchymal injuries US examination revealed irregular areas of inhomogeneous reflectivity. Radiological evaluation of kidney in patients which sustained abdominal trauma is generally indicated in patients with hypotension < 90 mm Hg and hematuria. CT is preferred image method, enabling evaluation of the injury category. CT is essential in qualifying of patients for conservative or surgical management. USG is also useful in initial diagnosis, but usually precise renal evaluation requires additional CT examination.