Appendix of testis
| Appendix of testis | |
|---|---|
 The right testis, exposed by laying open the tunica vaginalis (appendix of testis is labeled at right) | |
| Details | |
| Precursor | Müllerian duct |
| Latin | Appendix testis |
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.
Clinical significance
Although it has no physiological function, it can be medically significant in that it can, occasionally, undergo torsion (i.e. become twisted), causing acute one-sided testicular pain and may require surgical excision to achieve relief. 1/3 of patients present with a palpable "blue dot" discoloration on the scrotum. This is nearly diagnostic of this condition. Although if clinical suspicion is high for testicular torsion, a surgical exploration of the scrotum is warranted.
Occasionally a torsion of the hydatid of Morgagni can produce symptoms mimicking those created by a testicular torsion; a torsion of the hydatid, however, does not lead to any impairment of testicular function.