{{Short description|Part of the testis}} {{One source|date=December 2025}} {{Infobox anatomy | Name = Appendix of testis | Latin = appendix testis | Image = Gray1148.png | Caption = The right testis, exposed by laying open the tunica vaginalis (''appendix of testis'' is labeled at right) | Image2 = | Caption2 = | System = | Artery =Testicular artery | Vein = | Nerve = | Lymph = | Precursor = Paramesonephric duct |vein=Testicular vein, pampiniform plexus}} [[File:Ultrasonography of an appendix on a testicle in a hydrocele.jpg|thumb|Scrotal ultrasonography of an 85-year-old man with hydrocele, making the appendix of the testicle clearly distinctive as a 4 mm outpouching at upper right in image. Doppler shows some blood flow.]] The '''appendix testis''' (or '''hydatid of Morgagni''') is a vestigial remnant of the Müllerian duct, present on the upper pole of the testis and attached to the tunica vaginalis. It is present about 90% of the time.{{Citation needed|date=May 2021}}
==Clinical significance== ===Torsion=== The appendix of testis can occasionally become twisted, causing acute one-sided testicular pain and may require surgical excision to achieve relief. One third of patients present with a palpable "blue dot" discoloration on the scrotum. This is nearly diagnostic of this condition. If clinical suspicion is high for the serious differential diagnosis of testicular torsion, a surgical exploration of the scrotum is warranted. Torsion of the appendix of testis occurs at ages 0–15 years, with a mean at 10 years, which is similar to that of testicular torsion.<ref>{{cite journal|url=https://emedicine.medscape.com/article/778170-overview#a6|title=Torsion of the Appendices and Epididymis|author=Jason S Chang|website=Medscape|date=7 June 2022 }} Updated: Oct 20, 2016. Citing:<br>{{cite journal|last1=Nason|first1=Gregory J|last2=Tareen|first2=Farhan|last3=McLoughlin|first3=Danielle|last4=McDowell|first4=Dermot|last5=Cianci|first5=Fiona|last6=Mortell|first6=Alan|title=Scrotal exploration for acute scrotal pain: A 10-year experience in two tertiary referral paediatric units|journal=Scandinavian Journal of Urology|volume=47|issue=5|year=2013|pages=418–422|issn=2168-1805|doi=10.3109/00365599.2012.752403|pmid=23281617 |s2cid=3072304 |doi-access=free}}</ref>
==See also== * Paraovarian cyst
==References== {{Reflist}}
==External links== * {{eMedicine|emerg|595}} * {{WhoNamedIt|synd|292}}
{{Male reproductive system}} {{Authority control}}
Category:Mammal male reproductive system
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