Diagnosis and Treatment of Peritonsillar Abscess with Single Enhanced Computed Tomography

Abstract

Background and Objectives Diagnostic features of peritonsillar abscess are an asymmetrically enlarged palatine tonsil with peripheral rim enhancement and central low density in the post-contrast computed tomography (CT). Although it is necessary to differentiate tumorous conditions of tonsils to compare pre- and post-contrast CT, pre-contrast CT may be less useful in the diagnosis of peritonsillar abscess. This study aims to evaluate of the efficacy of single post-contrast CT for diagnosis and treatment of peritonsillar abscess. Subjects and Method We retrospectively compared 29 patients with peritonsillar abscess, who were diagnosed by single post-contrast CT, with 36 patients diagnosed by pre- and post-contrast CT to determine the success rates of pus drainage and hospital days. Additionally, two otorhinolaryngologists made a judgment of abscess presence for sixty randomly mixed CT images of peritonsillar abscess or tonsillitis with pre- and post-contrast CT or single post-contrast CT. Results There were no significant differences in the success rate of drainage (p=0.622) and hospital days (p=0.504) between groups with/without pre-contrast CT. Abscess presence was judged by raters with/without pre-contrast CT. Inter-rater agreement value (Cohen’s kappa) was 0.825 (p＜0.01). Conclusion Single post-contrast CT of peritonsillar abscess may be a good alternative for diagnosis and treatment and may reduce unnecessary exposure to radiation. Key words: Computed tomography ㆍ Contrast media ㆍ Peritonsillar abscess ㆍ Sensitivity ㆍ Specificity