A perforated appendix is one of the complications of acute appendicitis. If appendicitis is left untreated, ischaemic necrosis of a portion of appendiceal wall may occur, leading to perforation. An appendicolith is thought to be associated with a higher probability of perforation 1.
Perforation of the appendix is more common among the elderly population due to an increased frequency of late and atypical presentation of appendicitis, delay in diagnosis, delayed decision for surgery and to the age-specific physiological changes 2.
Computed tomography can provide a high degree of sensitivity (95%) and specificity (95%) for perforation in patients with known appendicitis if certain findings are present 1. Specific findings on a CT study include 3:
- periappendiceal abscess
- obvious demonstrable defect in the appendiceal wall
- extraluminal air locules or free intraperitoneal gas
- appendicolith outside the appendix or within the right iliac fossa abscess
- intraperitoneal leak of rectal contrast
Less specific findings include
- "moderate" periappendiceal phlegmon
- a defect in appendiceal wall enhancement (some consider this a more specific sign)
- peritoneal enhancement
Although ultrasound is less accurate than a contrast enhanced CT, the findings can be appreciated in experienced hands. Diagnosis of perforated appendix relies mainly on demonstration of right iliac fossa abscess or phlegmon in association with signs of appendiceal inflammation and appendicolith.
- 1. Pinto Leite N, Pereira JM, Cunha R et-al. CT evaluation of appendicitis and its complications: imaging techniques and key diagnostic findings. AJR Am J Roentgenol. 2005;185 (2): 406-17. doi:10.2214/ajr.185.2.01850406 - Pubmed citation
- 2. Omari AH, Khammash MR, Qasaimeh GR et-al. Acute appendicitis in the elderly: risk factors for perforation. World J Emerg Surg. 2014;9 (1): 6. doi:10.1186/1749-7922-9-6 - Pubmed citation
- 3. Horrow MM, White DS, Horrow JC. Differentiation of perforated from nonperforated appendicitis at CT. Radiology. 2003;227 (1): 46-51. doi:10.1148/radiol.2272020223 - Pubmed citation
The appendix can be affected by numerous inflammatory, infectious and neoplastic conditions:
- appendiceal mucocele
- appendiceal intussusception
neoplasms of the appendix
- appendiceal epithelial neoplasms
- appendiceal neuroendocrine tumours
- appendiceal lymphoma