Rennie Qin is a general surgery registrar at Waikato District Health Board. A graduate of the University of Auckland in 2016, she received the Gordon Gordon-Taylor medal for the highest mark in the Generic Surgical Sciences Examinations in 2019. She is interested in general surgery and global surgery.
Do the Eyes’ Have it? How Accurate is Surgeons’ Assessment of the Appendix?
Aims: The management of a normal appendix encountered at laparoscopy for right iliac fossa pain depends on the accuracy of surgeons’ assessment of the appendix. This study aims to determine the accuracy of intra-operative assessment compared to the gold standard of histopathological examination and identify predictors of disagreement.
Method: All appendicectomies in adults aged 15 years and over at Waikato District Health Board in the year 2017 were retrospectively reviewed. Data on demographic characteristics, pre-operative investigations, operation note, and histology report were collected. Operative and histological assessment of the appendix were categorized as normal, appendicitis, neoplasia, and other. The operation note was compared to the histopathologic report. The accuracy of the operative assessment was compared between groups based on training levels, patient gender, pre-operative imaging, and other pathology found on laparoscopy.
Results: 420 patients were included in the final study. 73 appendixes appeared normal on laparoscopy; however, 15 (20.5%) were found to have appendicitis on histology. Surgeons found 349 appendixes to be inflamed; however, 19 (5.4%) turned out to be histologically normal. Among 15 appendiceal neoplasms found on histology, only 2 were identified at the time of laparoscopy. Overall, there was disagreement in 11.1% of cases. This yields a kappa of 0.66, indicating only moderate inter-rater reliability. The accuracy of operative assessment did not significantly differ between non-trainee registrars, trainee registrars, and consultants. An inflamed appendix is significantly more likely to be falsely assessed to be normal in female patients, those who had a pre-operative ultrasound, and those with an alternative gynaecological diagnosis found on laparoscopy. A pre-operative computerized tomography scan; however, is associated with significantly less false negatives.
Conclusion: Intra-operative assessment of the appendix can lack accuracy especially in certain patient groups. This has implications for the removal of a normal-appearing appendix as pathology could be missed.