Objective To quantify the trends in imaging use for the diagnosis of appendicitis. Methods Retrospective study at an academic medical center over a 22-year period. Patients were identified by ICD-9 diagnosis code for appendicitis. Medical record data extraction of these patients included imaging test used (ultrasound, CT, or MRI), gender, age, and body mass index (BMI). The proportion of patients undergoing each scan was calculated by year. Regression analysis was performed to determine whether age, gender, or BMI affected the imaging choice. Results There were 2108 patients in this study, including 967 (43.5%) females and 599 (27%) children (<18 years old). CT use increased over time for the entire cohort (2.9% to 82.4%, p<0.0001) and each subgroup (males, females, adults, pediatrics, p<0.0001 for each). CT use increased more in females and adults than males and pediatric patients, though the differences in trends were not statistically significant (male vs. female p=0.8, adult vs. pediatric p=0.1). The percentage of patients who had no imaging used for the diagnosis of appendicitis decreased over time (p<0.0001 overall and each subgroup), and there was no difference in trends between complementary subgroups (males vs. female p=0.53, adults vs pediatrics p=0.66). There were no statistically significant changes in the use of ultrasound or MRI over the study period. With increasing BMI, CT was more frequently used. Conclusion Of those diagnosed with appendicitis at an academic medical center, CT use increased over 20-fold. However, there was not a statistically significant trend towards increased use of ultrasound or MRI.