CT differentiation of abscess and non-infected fluid in the postoperative neck

• Published in: Acta radiologica (1987) Vol. 54; no. 1; p. 48
• Main Authors: Yoon, Soo Jeong, Yoon, Dae Young, Kim, Sam Soo, Rho, Young-Soo, Chung, Eun-Jae, Eom, Joong Sik, Lee, Jin Seo
• Format: Journal Article
• Language: English
• Published: England 01.02.2013
• Subjects: Abscess - diagnostic imaging; Adult; Aged; Chi-Square Distribution; Contrast Media; Diagnosis, Differential; Drainage; Female; Head and Neck Neoplasms - surgery; Humans; Iohexol; Male; Middle Aged; Neck - diagnostic imaging; Postoperative Complications - diagnostic imaging; Retrospective Studies; Sensitivity and Specificity; Tomography, X-Ray Computed - methods
• ISSN: 1600-0455
• DOI: 10.1258/ar.2012.120505

Differentiation of postoperative neck abscess from non-infected fluid is important because the treatment is different. To determine specific CT findings that might help to differentiate abscesses from non-infected fluid collections in the postoperative neck. We retrospectively reviewed CT scans of 50 patients (43 men and 7 women; mean age, 62.5 ± 8.9 years) who had postoperative fluid collections in the neck (26 abscesses and 24 non-infected fluid collections). Diagnosis of an abscess was determined by a positive bacteria culture from the fluid collection. Diagnoses were correlated with the following CT findings: anatomic spaces involved, the maximum transverse diameter, margin, attenuation, rim enhancement, gas bubbles, and manifestations of soft tissue adjacent to a fluid collection. Rim enhancement pattern and soft tissue manifestations showed significant differences between abscess and non-infected fluid. The reliable CT findings for abscess were: (i) rim enhancement > 50% of the circumference, 54% sensitive, 71% specific, and 62% accurate; and (ii) severe soft tissue manifestations, 39% sensitive, 92% specific, and 64% accurate. There were no significant differences in the anatomic spaces involved, the maximum transverse diameter, margin, attenuation, and gas bubbles between abscess and non-infected fluid. CT findings that may help differentiate postoperative neck abscess from non-infected fluid were rim enhancement > 50% of the circumference and severe soft tissue manifestations.