April 30, 2007

ACR Radiology Coding Source March-April 2007

Obstetrical Ultrasound Coding and the Radiology Report

Obstetrical (OB) ultrasound studies must be well documented in order to support the CPT® code(s) chosen. The CPT code book lists the required elements for all OB ultrasound codes, and gives instructions to look for all of these elements in the radiology report in order to choose a complete study code. This article summarizes the OB codes and identifies when they should be reported. 

The current complete OB ultrasound codes include: 76801, 76802, 76805, 76810, 76811, 76812, and 76817. If a complete study is intended, but one of the required elements cannot be visualized (eg, obscured by bowel gas or surgically absent), the reason for non-visualization must be documented in the report in order to assign a complete study CPT® code.1 Without this documentation, the limited study code, 76815, should be assigned. 

Other codes in the OB ultrasound section of CPT® include 76816, a special code for follow-up examinations of fetal size or fetal organ systems; 76818 through 76821 for biophysical profiling and Doppler velocimetry; and 76813 and 76814, nuchal translucency measurement codes that were described recently in the September/October 2006 ACR Radiology Coding Source as part of the 2007 CPT® code update. 

Radiology Report Documentation 
76801, 76805, 76811, 76817

Coding questions commonly brought forward by coders of OB ultrasound fall into two categories. First, lack of understanding of the study's technical aspects and of the terminology used in the reports often results in an inability to determine whether all the required elements are, in fact, documented. Second, there is sometimes confusion about assignment of an OB ultrasound code vs an abdominal or non-OB pelvic ultrasound code. 

When the pregnancy is in the first trimester (less than 14 weeks), the coder should remember that the required elements for CPT® code 76801 will be those that are "appropriate for gestation" and "visible." 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 any of the elements are not documented, the limited OB ultrasound study should be assigned (76815).2 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. 

The most common or standard OB ultrasound study performed after the first trimester is described by CPT code 76805. The number of gestations and examination of the maternal adnexa are required as they were for 76801. Now, however, the pregnancy has progressed enough that more information about the fetus may be obtained from the study, and so additional required elements must now be documented. Measurements that are now appropriate for gestational age include biparietal head diameter, abdominal and head circumferences, and femur length. Often coders will find this information documented by the abbreviations BPD, AC, HC, and FL. 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. 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. The coder needs to be sure all the elements are documented in order to assign 76805. Again, documentation of any reason why an element was not measured or visible will be sufficient to satisfy this requirement. 

Assignment of OB ultrasound code 76811 would only be done if the report contains all the elements necessary for code 76805, and then adds detailed evaluation of the fetal anatomy, specifically the brain/ventricles, face, heart/outflow tracts, specific abdominal organs, all of the limbs, and umbilical cord/placenta. It is important to mention here that for each of these codes, 76801, 76805, and 76811, there is a companion CPT® code to use for each additional gestation/fetus — 76802, 76810, and 76812. Report documentation is the same for each additional fetus as for the first fetus examined. 

A transvaginal OB ultrasound examination is coded with 76817. While this type of examination is usually done early in the pregnancy, it may be done at a later time. If this exam is done in the first trimester, the same requirements for use of 76801 apply.3 If a transvaginal exam is performed at the same time as another OB ultrasound study, both may be coded.4 

76815, 76816, 76819, 76820

CPT® codes 76815 and 76816 are appropriate when an OB ultrasound study is performed and the report does not document a complete study as outlined above. When a study is performed that lacks any of the requirements of a complete study, 76815 may be assigned. Code 76815 also would be used for an intended quick look or selected limited examination of any individual element of any OB study, such as amniotic fluid assessment. 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 re-evaluate any fetal organ-system abnormality noted on a previous ultrasound study, 76816 is appropriate. 

A biophysical profile consists of five elements — four of which are studied with ultrasound, and the fifth element, which involves a nonstress test usually administered by the patient's obstetrician. The four elements that are scored from an ultrasound study are amniotic fluid, breathing, gross body movements, and fine motor movements. A score of "2" or "0"is given for each element, and the radiology report will give the score received out of the possible 8 points, in the format "8/8". Reporting of this score satisfies the required documentation of the study being performed. The fetus must be observed under ultrasound for a specified period of time to determine if the body movements are present. Correct coding for the biophysical profile score of the four elements (without nonstress testing) is 76819. This code may be assigned as a stand-alone service, or may be assigned in addition to any other OB ultrasound study performed at the same encounter. Code 76819 is reported per fetus. A biophysical profile performed along with a nonstress test is coded 76818. A nonstress test performed without a biophysical profile is coded 59025. 

Doppler evaluation may be performed, and there are CPT codes in the OB ultrasound section for two sites: the umbilical cord, 76820, and the middle cerebral artery, 76821. This measurement would normally be done later in the pregnancy. For the umbilical Doppler study, look for this to be reported with the ratio of systolic to diastolic flow rates terminology "S/D ratio". These codes may be assigned in addition to any other OB ultrasound study performed at the same encounter, and are reported per fetus. 

Use of OB Ultrasound Codes Versus Non-OB Ultrasound Codes

Questions commonly arise concerning the many scenarios in which ultrasound studies are performed that involve pregnancy-related indications, no pregnancy-related indications, pregnancy previously diagnosed or not diagnosed, etc. There are many permutations of these circumstances, and coders usually are not sure if the use of OB ultrasound codes relies on whether there is a known pregnancy, and if so, whether that needs to be diagnosed prior to the exam, or confirmed by the exam. 

CPT states, through its companion publication, the CPT Assistant,5 that the use of OB ultrasound codes are appropriate anytime the patient has been established to be pregnant, by any method or means, and the indications for the ultrasound study might be or could be pregnancy-related, regardless of whether the outcome might not confirm a pregnancy, or might produce a diagnosis that is not pregnancy-related. For the patient who has not been diagnosed as pregnant, and the indications for the ultrasound study are not pregnancy-related, the use of non-OB ultrasound codes is appropriate, regardless of whether the outcome of the study shows a pregnancy or complication related to pregnancy. 


1 CPT® 2007, Professional Edition, p. 308 

2 Clinical Examples in Radiology, vol 3:7, Winter 2007 

3 ACR 2006 Ultrasound Coding User's Guide, p. 15 

4 CPT Changes 2003, p. 191 

5 CPT Assistant, October, 2001