Understand the coding mechanics behind some of the most common obstetrical US examinations.
An outsider looking in might think diagnostic radiology coding is as simple as knowing the number of views of an X-ray or whether contrast was used on a computed tomography (CT) or magnetic resonance imaging (MRI) scan. But to say that’s even the tip of the iceberg would be an understatement.
The reality is that you’ve got to be cognizant of a handful of guidelines dedicated to each diagnostic subcomponent within the radiology specialty. With the plethora of rules and guidelines to consider, obstetrical ultrasound (US) coding is almost a subspecialty in its own right.
Let’s dive into the coding dynamics behind one of the many staples of diagnostic radiology coding: obstetrical US.
Meet This Set of 76801 Criteria
A good chunk of diagnostic radiology coding involves using a theoretical (and sometimes literal) checklist to confirm you’ve got enough components and elements documented to achieve a given code. When it comes to obstetrical US coding, this checklist concept becomes especially important because your CPT® coding depends on it. The CPT® code book lays out a strict set of criteria necessary to reach a given obstetrical US code that varies depending on certain diagnostic components, such as trimester.
Start out with a look at the criteria you’ll need to meet to report codes 76801 Ultrasound, pregnant uterus, real time with image documentation, fetal and maternal evaluation, first trimester (< 14 weeks 0 days), transabdominal approach; single or first gestation and +76802 … each additional gestation (List separately in addition to code for primary procedure):
- Determination of the number of gestational sacs and fetuses;
- Gestational sac/fetal measurements appropriate for gestation (younger than 14 weeks, 0 days);
- Survey of visible fetal and placental anatomic structure;
- Qualitative assessment of amniotic fluid volume/gestational sac shape; and
- Examination of the maternal uterus and adnexa.
What’s first important to note is that you do not always have to meet each of the above criteria to report 76801/+76802. As per American College of Radiology (ACR) guidelines, the required elements for 76801 are “appropriate for gestation” and “visible.” The ACR explains “if any of the elements listed in the CPT® code book are not able to be measured or are not visible, then the report should document that information in order to assign 76801.”
If the report inadequately documents why one or more of the above criteria is missing, then you should either query the physician regarding an addendum or report the limited obstetrical US code 76815 Ultrasound, pregnant uterus, real time with image documentation, limited (eg, fetal heart beat, placental location, fetal position and/or qualitative amniotic fluid volume), 1 or more fetuses in place of 76801.
Know When to Factor in Amniotic Fluid Assessment
Determining whether the physician’s documentation meets the criteria for the assessment of amniotic fluid can be challenging. The ACR explains that “among the required elements, ‘qualitative assessment of amniotic fluid volume’ refers to the radiologist’s statement, based on his or her experience and knowledge, that the volume is adequate or inadequate.”
Amniotic fluid is never mentioned on the earliest obstetrical USs of seven or eight weeks gestation because the assessment doesn’t typically become relevant until weeks 13 or 14. Most often, amniotic fluid will be evaluated and documented on the fetal anatomical structural evaluation at around 18 to 20 weeks.
When providers document “no free fluid” on the seven- to eight-week fetal US, they are referring to free fluid within the peritoneal space, not amniotic fluid.
Compare and Contrast 76801 With 76805
You’ll find a similar set of criteria for codes 76805 Ultrasound, pregnant uterus, real time with image documentation, fetal and maternal evaluation, after first trimester (> or = 14 weeks 0 days), transabdominal approach; single or first gestation and +76810 … each additional gestation (List separately in addition to code for primary procedure):
- Determination of the number of fetuses and amniotic/chorionic sacs;
- Measurements appropriate for gestational age (older than or equal to 14 weeks, 0 days);
- Survey of intracranial/spinal/abdominal anatomy;
- Four-chambered heart;
- Umbilical cord assessment;
- Placenta location and amniotic fluid assessment; and
- Examination of maternal adnexa, when visible.
With respect to the “survey of intracranial/spinal/abdominal anatomy,” the ACR explains exactly what you should be looking for within the report:
Mention will need to be made of the head, spine, and abdominal anatomy along with the heart and umbilical cord insertion site. This will be in a “survey” format, and detail may not be provided.
You may consider that portion of the criteria for 76805 accounted for as long as the radiologist documents each respective anatomical component as “normal” or otherwise. Usually included in a survey of the intracranial, spinal, and abdominal anatomy is documentation of a four-chambered heart and a three-vessel umbilical cord.
Fetal Measurement Abbreviations
For second and third trimester US, you’ll come across a variety of fetal measurement abbreviations included in the physician’s dictation report templates. These abbreviations and their respective measurements will act as sufficient documentation to check off a required element. Examples include:
- BPD – Biparietal diameter
- HC – Head circumference
- AC – Abdominal circumference
- FL – Femur length
- OFD – Occipitofrontal diameter
- CI – Cephalic index
- HA ratio – Head to abdomen ratio
- EFW – Estimated fetal weight
- AFI – Amniotic fluid index
Go a Little Further With 76805 Criteria
Although amniotic fluid index (AFI) is not specifically documented as a key element, documentation should include amniotic fluid measurement with the second element for 76805: Measurements appropriate for gestational age (older than or equal to 14 weeks, 0 days). The ACR adds:
After the first trimester, the amniotic fluid might be measured (quantitative), or the report may document this with a qualitative assessment — either is acceptable. If measured, this might also appear in the report simply as an abbreviation and a number.
Just as you would with 76801, you may still report 76805 for an unaccounted-for element if the provider documents why the element could not be visualized or measured. If the provider fails to elaborate on the missing element, either query the physician as to whether an addendum is needed or report code 76815 instead of 76805.
Other Requirements for 76811 Reporting
When coding for a patient in their second or third trimester, you may have to make the distinction between a traditional US (76805) and its more detailed counterpart, 76811 Ultrasound, pregnant uterus, real time with image documentation, fetal and maternal evaluation plus detailed fetal anatomic examination, transabdominal approach; single or first gestation. This involves a thorough analysis of the dictation report.
In addition to each of the elements needed to meet the requirements for 76805, the provider must also document the following to code 76811:
- Detailed anatomic evaluation of the fetal/brain ventricles;
- Face, heart/outflow tracts, and chest anatomy;
- Abdominal organ specific anatomy; and
- Number/length/architecture of limbs and detailed evaluation of the umbilical cord and placenta and other fetal anatomy as clinically indicated.
When discerning between 76805 and 76811, do not make a coding determination based on exam header alone. In some cases, the exam header may be formulated to state nothing more than the exam involves a 14-week or greater US examination.
Outside of any extenuating circumstances, the provider usually has no need to perform a more substantial evaluation than what’s included in 76805. To qualify for 76811, the provider must document each element listed. Similar to 76805, if the provider does not document a given element, the dictation report should include a reason for non-visualization.
Consider Quick Look Exam Coding Scenarios
If you’re coding a report in which the provider does not document enough elements to reach the complete fetal and maternal evaluation codes, then you should resort to coding 76815. This exam is referred to as a “quick look” exam and includes one or more elements listed in the code description.
The ACR elaborates a little further on code 76815:
It is important to note that 76815 includes in its code description, “one or more fetuses,” and should not be coded more than once per study, or per fetus. If a study is done to reassess fetal size, or to reevaluate any fetal organ-system abnormality noted on a previous ultrasound study, 76816 is appropriate.
Without a thorough examination of the report and surrounding context, it’s easy to mistakenly assign code 76815 when the documentation actually supports code 76816 Ultrasound, pregnant uterus, real time with image documentation, follow-up (eg, re-evaluation of fetal size by measuring standard growth parameters and amniotic fluid volume, re-evaluation of organ system(s) suspected or confirmed to be abnormal on a previous scan), transabdominal approach, per fetus. Begin with a few important notes offered in the CPT® code book:
Code 76816 describes an examination designed to reassess fetal size and interval growth or reevaluate one or more anatomic abnormalities of a fetus previously demonstrated on ultrasound, and should be coded once for each fetus requiring reevaluation using modifier 59 for each fetus after the first. If a study is done to reassess fetal size, or to re-evaluate any fetal organ-system abnormality noted on a previous ultrasound study, 76816 is appropriate.
Code This Real-World Example
In the following case study, your first point of order in distinguishing between codes 76801, 76805, 76811, 76815, and 76816 is to examine the clinical indication. If the clinical indication states that it’s a follow-up obstetrical US, you need to check the patient’s chart history to determine the correct code. Keep in mind that the exam header for a fetal reassessment may look identical to that of a complete fetal and maternal evaluation as described in code 76805. Put what you’ve learned to the test by coding the following clinical example.
Example: Patient admitted to emergency room (ER) for vaginal bleeding in pregnancy. A transvaginal obstetrical US is performed. The radiologist documents two subchorionic bleeds with a gestational age of eight weeks and three days. One week later, the patient presents for a first-trimester fetal and maternal US evaluation. The indication reads: “Evaluation of early pregnancy for dating. Follow-up of subchorionic hematomas.” One week following, the patient returns for a follow-up fetal and maternal US evaluation. The indication reads: “Follow-up of subchorionic hematomas.”
There are more than a few instances in this patient scenario that can cause problems for a coder. The first exam is relatively straightforward. The patient presents to the ER for a transvaginal obstetrical US. Given the circumstances of this exam, you should not consider any obstetrical US code outside of 76817 Ultrasound, pregnant uterus, real time with image documentation, transvaginal. Code 76801, for instance, is a planned transabdominal procedure that involves an extra set of criteria not included in 76817. Where this situation gets tricky is when you look at the planned evaluation one week following the ER encounter.
Assuming this exam at the second encounter includes all the necessary criteria to report 76801, you should code it as such. However, there’s plenty of room to get tripped up when examining the indicating diagnosis. Obstetrical radiology coders are often conditioned to see “follow-up” in the indication and immediately opt for code 76816. Evaluating the patient’s entire obstetrical examination history before making any coding considerations is always important.
Looking at the bigger picture, the “follow-up” is in reference to the original ER visit, not a prior fetal and maternal evaluation exam. Since this fetal and maternal evaluation occurs at approximately nine weeks, the next point of order is to evaluate the dictation report to confirm that the exam meets all the required elements for 76801 coding.
Lastly, you’ve got to make a coding determination regarding the third and final follow-up examination. Based on the clinical indication and chart history, this third examination qualifies as a true follow-up obstetrical examination. Similar to the example above, providers will routinely order these exams for patients with documented subchorionic bleeding to make sure the hematoma has not progressed. As long as this exam meets the necessary CPT® elements, you will report code 76816.
Brett Rosenberg, MA, CPC, COC, CCS-P, serves as the editor of The Coding Institute’s (TCI’s) Radiology, Otolaryngology, and Outpatient Facility Coding Alerts. He earned his bachelor’s degree in psychology from the University of Vermont in 2011 and his master’s degree in psychology from Medaille College in 2016. Rosenberg is affiliated with the Flower City Professional Coders local chapter in Rochester, N.Y.