الفهرس 
Normal radiological anatomy of the kidneyOnly 14 pages are availabe for public view
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Abstract
Renal trauma is seen approximately in 8-10% of patients with sustained blunt or penetrating abdominal trauma.
Blunt impact injury is far more common than penetrating injury accounting for 66-90% of cases of renal injury.
Radiologists serve an integral role in the multi -disciplinary approach to achieve that goal, playing a large part in the diagnosis and staging of injuries.
In plain film radiography secondary findings may be seen as rib fracture, asymmetry of soft tissues overlying the flanks, and asymmetry of psoas muscle shadows may suggest possible renal injury.
Finding that may be revealed by IVU include loss of renal outline or psoas shadow if there is perinephric hemorrhage, diminished or absent excretion, or contrast extravasation.
Angiography is required to assess if the lesion is amenable of treatment. Aortography is used to evaluate the basic anatomy and then selective renal angiography will be performed. Angiography will determine if the management could be endovascular or surgical.
Ultrasound serves a screening function it assesses the presence of free fluid in the abdomen or pericardium but does not explicitly identify the source.
Ultrasound is considered most useful in detection of solid organ injuries associated with hemoperitoneum.
Color-flow and gray-scale Doppler sonography can be used to diagnose and follow renal artery pseudo aneurysm; pseudo aneurysm appears as a rounded anechoic structure on gray-scale images, with to-and-fro swirling on color-flow images.
Across all imaging modalities, CT is the most comprehensive diagnostic tool for assessing patients with blunt abdominal trauma. CT can be used to evaluate a large breadth of intra-abdominal injuries with accuracy, and hence, it has a primary role in evaluating the trauma patient. Further, the success of CT in staging abdominal injuries has contributed to the growing trend toward nonoperative management of traumatic abdominal injuries.
The AAST grading system is applied to classify the severity of renal trauma and takes into account size and location of renal lacerations and hematomas. CT findings are correlated well with the AAST classification. An initial unenhanced study can be helpful in detecting acute bleeding or intraparenchymal injuries.
On contrast enhanced study, contusions appear as round or ovoid areas of decreased enhancement with ill-defined contours. Parenchymal lacerations appear on CT as hypodense linear or wedge shaped parenchymal defects or clefts. If lacerations contain blood clots, they may appear as hyperdense parenchymal defects.
A perinephric hematoma often appears as ill defined, hyper attenuating fluid collection located between the Gerota fascia and the renal parenchyma.
More often than not, such a hematoma is associated with underlying injury, though it can occur in isolation. Thus when a perinephric hematoma is discovered, a thorough investigation of the kidney should be undertaken to look for associated renal injury. Unlike a subcapsular hematoma, even a large perinephric hematoma does not traditionally deform the kidney.
Although MRI is not used in majority of renal trauma patients, MRI is accurate in detecting peri-renal hematoma, assessing the viability of renal fragments, and detecting pre-existing renal abnormalities, but fails to visualize the urinary extravasation on initial examination.
MRI is therefore useful in renal trauma only if CT is not available, in patients with iodine allergy, or in the very few cases where the findings on CT are equivocal.
In conclusion, medical imaging plays an important role in diagnosis& management of renal trauma.