Purpose: To retrospectively assess the impact of high-grade obstructions identified on initial CT on outcomes of patients with appendiceal inflammatory masses managed by nonoperative treatment.Methods: Institutional Review Boards approved this retrospective study and informed consent was waived. Included were 52 consecutive patients diagnosed with appendiceal inflammatory masses by CT scan and managed by nonoperative treatment. The main outcome measure was treatment failure and secondary outcomes were complications and initial and total hospital stay. Patient demographics, inflammatory markers, and CT findings for presence of an appendiceal inflammatory mass and high-grade obstruction were assessed. Patients with and without high-grade obstruction were compared for patient characteristics and outcomes using Fisher exact test and Student t-test.Results: Among 52 patients, 14 (27%) had high-grade obstruction on CT examination at presentation. No significant differences were observed in patient characteristics (P > 0.05), treatment failure (P = 0.33), complications (P = 0.29), or initial (P = 0.73) or total (P = 0.72) hospitalization between patients with and without high-grade obstruction.Conclusion: For patients who were managed by nonoperative treatment for appendiceal inflammatory masses, the presence of high-grade obstruction identified on initial CT scan did not significantly affect outcomes of treatment failure, complications, and initial and total hospitalization.