Question: New Jersey Subscriber Answer: All diagnostic ultrasound examinations require permanently archived images and a written interpretive report for inclusion in the medial record. CPT® language is often very specific in the description of the exact organs or anatomical structures to be mentioned in the interpretive report when choosing that particular code, so review those code descriptors and the relevant preambles carefully before choosing the code to describe your service. Pay particular attention to the complete vs. limited code descriptors. For example, CPT® instructs, "A complete ultrasound examination of the retroperitoneum (76770) consists of real time scans of the kidneys, abdominal aorta, common iliac artery origins, and inferior vena cava, including any demonstrated retroperitoneal abnormality. Alternatively,if clinical history suggests urinary tract pathology, complete evaluation of the kidneys and urinary bladder also comprises a complete retroperitoneal ultrasound." The expectation is that the interpretive report would note all the listed elements or an explanation as to why those elements could not be visualized. By contrast, code 76775 (Ultrasound, retroperitoneal [e.g., renal, aorta, nodes], real time with image documentation; limited) suggests that your scan was less than that required for the complete scan. Code 51798 (Measurement of post-voiding residual urine and/or bladder capacity by ultrasound, non-imaging) describes only the technical involvement of that service with no physician work included, and correspondingly carries a work value of zero, so using that code is harder to substantiate if you are only reporting the professional component of the service. This code appears in the urological section of CPT® rather than the diagnostic ultrasound section.