Physicians wanting an ultrasound of the abdomen, pelvis, or retroperitoneal area for their patients are faced with two choices: should they order a complete or a limited ultrasound? This post will clarify the differences between the two and help avoid denials and peer-to-peer calls when you seek prior authorization for an ultrasound.
Abdominal Ultrasound: Complete or Limited?
A complete ultrasound is defined as a sonogram that images and reports on all the organs and major structures within the anatomic region. For example, a complete abdominal ultrasound must include a real-time scan and radiologist’s description of the:
• gall bladder
• common bile duct
• abdominal aorta and
• inferior vena cava
• plus any abnormality within the abdomen
If a structure cannot be visualized or is missing, the report should document the reason.
A limited abdominal ultrasound does not need to include a description of every structure; instead the report usually describes only one or two findings. Limited US is used for follow-up imaging or to focus on a single structure. For example, limited US can be used for:
• monitoring a liver lesion to assess change in size over time.
• diagnosing ascites
• 6 month surveillance for hepatocellular carcinoma in a patient with chronic liver disease
• assessing diaphragm movement
• following an abdominal aneurysm for growth
The initial ultrasound scan of the abdomen is often coded as a complete imaging study (76700), and if an abnormality is found or if follow-up is required, the next study would be a limited ultrasound (76705).
Retroperitoneal US: Complete or Limited?
Guidelines for retroperitoneal US complete vs. limited are similar to those for abdominal US. A complete retroperitoneal US (76770) should include a scan and report that included all elements of the retroperitoneal space including:
• lymph nodes
• common iliac artery origins
• abdominal aorta
• inferior vena cava
Follow-up imaging may be performed with a limited retroperitoneal US (76775) in which a report needs only to describe one or two structures. An example of a limited retroperitoneal US would be to follow kidney stone that has appeared on a previous x-ray or ultrasound.
There are four types of pelvic ultrasound. The preferred imaging used to evaluate female pelvic pathology in adults is a trans-vaginal ultrasound (coded 76830 for non-pregnant patients or 76817 if pregnant). There is no corresponding procedure code for these two studies as limited studies, so both of these scans are coded as complete studies. The other two types of Pelvic ultrasounds are performed with the transducer placed on the lower abdomen (below the umbilicus). This scan is called a trans-abdominal pelvic US and has two codes: complete (76856) or limited (76857). Trans-abdominal pelvic US is preferred over trans-vaginal US in pediatric patients, non-sexually active females, and in men who need a pelvic US study. They can also be performed at the same time as a trans-vaginal US.
Complete Trans-abdominal pelvic US is used to image all organs in the pelvis and includes perineum, pelvic wall, buttocks, inguinal area, ovaries, fallopian tubes, uterus, bladder, and distal ureters. Limited trans-abdominal pelvic US is used to follow a single organ or structure, for example, to monitor an ovarian cyst. In males, limited pelvic US (76857) is used to image the penis, while 76870 is used for scrotum and contents.
Duplex Doppler scan of the pelvis (complete 93975 or limited 93976) can be added to pelvic ultrasound studies for many known or suspected diseases of the adnexa or scrotum.
Lesson#13: When requesting ultrasound imaging of the abdomen, pelvis, or retroperitoneal area, complete US is the preferred initial scan or if needed to view every organ or structure in that location. Follow-up imaging can often be accomplished with a limited study.