In this study, we sought to determine the rates of missed anatomy on standard CT scans obtained for genital pathology and found that this happens in about a quarter of scans obtained for this indication. As far as the authors are aware, this is the first study examining genital capture of CT scans in the literature. This research establishes the foundation for developing a genital pathology–specific CT protocol at our institution.

There were several interesting findings from this study. We found that a CT abdomen/pelvis was more commonly ordered over a CT pelvis (60% vs. 40%), which, for the purposes of assessing genital pathology, unnecessarily irradiates the abdominal organs. Eliminating unnecessary radiation exposure is a key concept in the development of CT protocols, and the reason why a CT pelvis does not extend to universally include the testicles [22,23,24]. Developing a genital pathology–specific CT protocol would not include the abdomen, thus eliminating unnecessary radiation exposure of the abdominal organs. Since patients with missed anatomy were more likely to obtain multiple scans during their admission (though not significant), a genital pathology–specific CT protocol could potentially decrease the rates of missed anatomy and also potentially reduce the radiation exposure from additional scans.

Though not the primary quality improvement focus of this study, we also found that 19% of presenting patients already had a scan from an outside hospital prior to arrival at our institution. Whether or not images from these scans were available or if they included full AOI was not measured in this study, but this represents a potential area for improvement that could also decrease unnecessary radiation exposure.

Unsurprisingly, inclusion of protocol-extending language decreased the rates of missed AOI, but only 38% of scans included any protocol-extending instruction. It was notable that protocol-extending request made by the ordering provider did not always lead to a protocol-extending instruction from the radiologist, though this did not seem to drastically affect missing AOI (only 1 of 9 scans fitting these criteria had missing AOI), suggesting that the CT technologist independently extends the protocol when requested by the ordering provider. Additionally, the protocoling radiologist requested a protocol extension without a request from the ordering provider only 10% of the time, which excludes radiologist discretion as a reliable method of extending scans when indicated based on reason for ordering.

While there is a high rate of concordance between reason for scan and diagnosis specifically for FG/NSTI and scrotal abscess, they only represent a small fraction of the entire study. It is also important to note the high rate of discordance between the reason for ordering scan and ultimate diagnosis, which further highlights the need for comprehensive imaging when genital pathology is suspected. There were 79 (70%) instances where the reasons for ordering the scan did not match the final diagnosis. The 65 (58%) cases where the reason for scan was designated “other”, included general and non-specific descriptors in the reason for scan (e.g. “lower abdominal pain”, “infection”, “skin lesion”, “fever”, “sepsis”). For the 26 index scans where AOI was excluded, 21 had a reason of scan investigator-designated as “other”. As a result, utilizing vague descriptors in the reason for exam when ordering CT imaging could lead to increased rates of AOI exclusion. The current mode of ordering CT imaging heavily relies on the proactivity of the ordering physician and radiologist; however, developing a comprehensive imaging protocol specifically for genital pathology may help eliminate these concerns and improve acquisition of AOI.

We are limited by the retrospective nature of this study and the relatively small sample size of CT scans. Additionally, 98% of patients in this study were male, limiting the applicability of this data to female patients. It is thus unclear if a genital-specific CT protocol would be of any benefit in female patients, though it is unlikely to lead to clinically significant irradiative consequences since the female gonads are universally irradiated from a CT pelvis. Some argument could be made for limiting the proximal extent of a genital-specific CT protocol to avoid scanning the pelvic organs completely, but this study was not designed to determine the feasibility of this, as we did not assess the likelihood of missing significant pathology in the setting of a proximally limited scan.

Furthermore, while this study examined the utilization of standard CT pelvis protocols on several diagnosed urologic conditions, the only CPT code utilized to identify these patients was for genital debridement. This could mean that we neglected to capture patients who underwent other operative interventions such as simple I&D, device explantation, or diversion for fistulae. However, utilizing the diagnostic codes for these conditions was felt to be more accurate for capturing these patients, as many are managed non-operatively initially or with bedside procedures. Though this study focused specifically on operative management for FG, creation of a genital-specific CT protocol would almost certainly have broad applications to all genital pathology.

This study was not designed to evaluate ultrasound evaluation of these pathologies and how diagnoses made by ultrasound might relate to CT scan results. Many patients who present to the ED with these types of conditions are initially (and sometimes only) evaluated by ultrasound, but the influence of ultrasound on CT ordering or patient management was not measured in the current study.

Since the completion of this cross-sectional study, we are working to implement a genital pathology–specific CT protocol at our institution, which would include a standard CT pelvis that starts from the iliac crest and extends to mid-thigh. Future directions of this work will include assessing rates of missed AOI after developing a genital–pathology-specific CT protocol at our institution. Ultimately, we hypothesize that development of a genital pathology–specific CT protocol will improve inclusion rates of AOI when genital pathology is suspected, reduce radiation exposure from additional CT imaging, improve surgical planning and medical management, and contribute to high-value patient care.