Master the Art of Obstetrical Ultrasound Coding
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
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.
Other Requirements for 76811 Reporting
- 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.
Consider Quick Look Exam Coding Scenarios
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.
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.