Histological Stages of Appendicitis Associated With Imaging Characteristics: A Computed Tomography and...

Appendicitis diagnosis relies heavily on medical imaging procedure studies; however, a definite diagnosis is obtained through histological assessment. Understanding the imaging characteristics and their relation to various histological phases enhance the quality of treatment recommendations. This study analyzed imaging characteristics of acute appendicitis in relation to its histological severity.

A cross-sectional study was conducted using data from a third-level hospital. Appendectomy specimens from patients with prior computed tomography (CT) scans or ultrasound (US) imaging were included. Histological stages were categorized into simple, suppurative, abscessed, and perforated phases, depending the presence of edema, vascular congestion, neutrophilic infiltrate into the muscular layer, microabscess formation, mucosal ulceration, purulent exudate, macroscopic pus, and perforation with transmural inflammation. Imaging features as fat stranding, presence of free fluid, contrast enhancement within the appendix, appendicolith detection, reactive lymph nodes in the vicinity, appendix diameter itself, increased echogenicity, and detecting heightened perfusion via Doppler imaging were compared across these stages.

Among 760 patients included (51.4% women, mean age 30.1 ± 5.3), 196 (25.8%) had CT scans and 361 (47.5%) had US. CT confirmed appendicitis in 59.2% of cases, yielded a negative result in 19.4%, and provided an inconclusive diagnosis in 21.4% of cases, commonly identifying fat stranding, free liquid, and contrast enhancement. US diagnosed appendicitis in 67.6% of cases, whereas 32.4% were reported as negative, with findings including increased echogenicity, Doppler perfusion, appendix identification, and free liquid in the right parietocolic gutter. All imaging characteristics were less prevalent in early stages compared to advanced stages, with a higher negativity rate in earlier stages.

Imaging findings are associated with the histopathological severity of appendicitis. Increased histopathological severity is associated with greater frequency of CT and US findings. These relations suggest the potential for managing appendicitis based on the histological phase suspected from imaging findings. Further research is warranted.