Variation in imaging outcomes associated with individual sonographers and radiologists in pediatric acute appendicitis: a retrospective cohort of 9271 examinations.

OBJECTIVE

To determine if individual sonographers and radiologists impact appendix visualization by ultrasound and utilization of computed tomography (CT) in children with suspected acute appendicitis.

MATERIALS AND

METHODS

Appendix ultrasound examinations performed at Cincinnati Children's Hospital Medical Center on Emergency Department patients ≤ 18 years old were retrospectively identified. Examinations performed/interpreted by sonographers/radiologists with fewer than 100 examinations were excluded. Multivariable logistic regression was used to assess the effect of sonographer, radiologist, clinical variables, and system factors on imaging outcomes, including appendix visualization and subsequent CT utilization.

RESULTS

A total of 9271 ultrasound examinations (mean [SD] patient age, 9.9 [4.2] years; 5392 [58.2%] boys) performed by 31 sonographers (mean number examinations, 299 [139]; range, 115-610) and interpreted by 31 radiologists (mean number examinations, 299 [157]; range, 101-845) were included. The mean frequency of appendix visualization per sonographer was 57.8% [8.7%] (range, 40.9-76.0%) and per radiologist was 59.5% [4.1%] (range, 51.7-66.3%). The mean rate of CT utilization per sonographer was 9.2% [2.0%] (range, 5.9-14.0%) and per radiologist was 9.2% [1.8%] (range, 3.4-12.1%). Predictors of appendix visualization by ultrasound included patient weight (p < 0.0001), sex (p = 0.0003), white blood cell count (p < 0.0001), temperature (p = 0.002), abdominal tenderness (p = 0.004), presence of appendicitis (p < 0.0001), sonographer (p < 0.0001), and radiologist (p = 0.02). Predictors of CT utilization included patient weight (p < 0.0001), white blood cell count (p < 0.0001), abdominal tenderness (p < 0.0001), rebound tenderness (p = 0.0003), and presence of appendicitis (p < 0.0001), but not sonographer or radiologist.

CONCLUSION

Individual sonographers and radiologists were associated with appendix visualization by ultrasound in children with suspected acute appendicitis; neither was associated with CT utilization.

KEY POINTS: • Individual sonographers and radiologists are significantly and independently associated with appendix visualization by ultrasound in children with suspected acute appendicitis. • Frequency of appendix visualization per sonographer demonstrated significant and wide variability across 31 sonographers, ranging from 40.9 to 76.0%. • Fewer than 10% of patients with an ultrasound examination for suspected acute appendicitis underwent CT imaging within the following 24 h. Individual radiologists and sonographers were not predictive of CT utilization within 24 h.