Duplex appendix

Congenital

abnormalities and anatomical variations of the vermiform appendix and mesoappendix: Modified Cave-Wallbridge classification. Type A, partial duplication of the appendix; Type B1 (bird type), two appendices are placed symmetrically on both sides of the ileocecal valve; Type B2 (taenia coli type), one appendix is in the usual place and the other is far along the taenia coli; Type C, duplication of cecum and appendix; Type D (horseshoe type), one appendix has two openings in the cecum; Bulut et al. (2016).

www.sciencedirect.com • CC-by-nc-nd-4.0

Case report

of the duplex vermiform appendix: A rare presentation in an elderly patient: Table 1. Showing the modified Cave-Wallbridge classification

www.sciencedirect.com • CC-by-4.0

Duplex

appendix • Duplex appendix (illustrations) - Ganzer Fall bei Radiopaedia

Majumder P, Duplex appendix (illustrations). Case study, Radiopaedia.org (Accessed on 07 Oct 2023) https://doi.org/10.53347/rID-27041 • CC by-nc-sa 3.0 (modified)

Duplex

appendix • Double appendix - Ganzer Fall bei Radiopaedia

Shetty A, Double appendix. Case study, Radiopaedia.org (Accessed on 07 Oct 2023) https://doi.org/10.53347/rID-27036 • CC by-nc-sa 3.0 (modified)

Duplex

appendix • Duplicated appendicitis - Ganzer Fall bei Radiopaedia

Elkholy R, Duplicated appendicitis. Case study, Radiopaedia.org (Accessed on 07 Oct 2023) https://doi.org/10.53347/rID-66630 • CC by-nc-sa 3.0 (modified)

Duplex

appendix • Duplex appendix - type A - Ganzer Fall bei Radiopaedia

Essam M, Duplex appendix - type A. Case study, Radiopaedia.org (Accessed on 07 Oct 2023) https://doi.org/10.53347/rID-28286 • CC by-nc-sa 3.0 (modified)

Acute

abdominal pain presenting as a rare appendiceal duplication: a case report. Coronal computed tomography images depicting the appendiceal duplication (arrows).

jmedicalcasereports.biomedcentral.com • CC-by-2.0

Radiopaedia • CC-by-nc-sa 3.0 • de

Duplex appendix is a rare anomaly of the appendix and is usually discovered incidentally during surgery for appendicitis.

Epidemiology

Duplication of the vermiform appendix is extremely rare. It is found in only 1 in 25,000 patients (incidence ~0.004%) operated on for acute appendicitis. Although duplication anomalies are uncommon, they have clinical and medicolegal significance.

A case is also reported in which a child had two appendectomies performed in a 5 month period.

Classification

This classification was proposed by Wallbridge in 1963, and at the time of writing (July 2016) remains the most widely accepted classification.

The Cave-Wallbridge classification divides appendix duplications into three types:

type A: single cecum with one normally localized appendix exhibiting partial duplication
type B: single cecum with two completely separate appendices and divided into two further subgroups
- type B1 (‘bird-like type’): two appendices located symmetrically on either side of the ileocecal valve, resembling the normal arrangement in birds
- type B2 (‘taenia coli’ type): one appendix arises from the cecum at the usual site, and the second branches at varying distances along the lines of the taenia from the first
type C: double cecum, each bearing its own appendix

Some authors have since described further types of complex multiplicity of the appendix. For example, "horseshoe appendix", "duplicated appendix and cecum", and "triple appendix" but these are often only diagnosed at surgery and not with imaging.

Pathology

Associations

When anomalies of the appendix are detected in childhood they are nearly always associated with severe intestinal, genitourinary or bony malformations, seen most often in conjunction with type B1 and C duplications.