CAMRT Radiography Practice Exam

What condition does a nephrogram help diagnose if the kidney does not completely fill?

1. Kidney stones

2. Renal tumors

3. Potential blockage

4. Kidney infections

The correct answer is: Potential blockage

A nephrogram is an imaging study typically done using a contrast agent that highlights the kidneys, allowing for visualization of their structure and function. When interpreting a nephrogram, the complete or incomplete filling of the kidney with contrast can reveal important information about its condition. In the case of incomplete filling of the kidney during a nephrogram, this indicates that there may be an obstruction or blockage affecting the normal flow of urine from the kidney. Such blockages can be caused by various factors, including kidney stones or strictures, which impede the normal function and drainage of the urinary system. The nephrogram can help identify these issues by showing areas of the kidney that are less opacified, suggesting they are not receiving the contrast agent effectively due to obstruction. While the other conditions listed—kidney stones, renal tumors, and kidney infections—can also impact kidney function and structure, the specific indicator of incomplete filling strongly points towards the likelihood of a potential blockage. Incomplete nephrogram filling is particularly associated with urinary obstruction as it reflects a disruption in normal renal perfusion and drainage dynamics, leading to potential complications if not assessed and treated. Thus, this scenario is best interpreted as a potential blockage in the urinary system.