An examination using cystoscopy, where a flexible tube is inserted in the urethra, may show disease of the vesicles because of changes in the normal appearance of the nearby bladder trigone, or prostatic urethra. Other animals
The evolution of seminal vesicles may have been influenced by sexual selection. They occur in many groups of mammals, but are absent in marsupials, monotremes, and carnivoras. The function is similar in all mammals they are present in, which is to secrete a fluid as part of semen that is ejaculated during the sexual response. History
The action of the seminal vesicles has been described as early the second century AD by Galen, as "glandular bodies" that secrete substances alongside semen during reproduction. By the time of Herophilus the presence of the glands and associated ducts had been described. Around the time of the early 17th century the word used to describe the vesicles, parastatai, eventually and unambiguously was used to refer to the prostate gland, rather than the vesicles. The first time the prostate was portrayed in an individual drawing was by Reiner De Graaf in 1678.The first described use of laparoscopic surgery on the vesicles was described in 1993; this is now the preferred approach because of decreased pain, complications, and a shorter hospital stay.
A gangliocytic paraganglioma  is a rare tumour that is typically found in the duodenum and consists of three components: (1) ganglion cells, (2) epithelioid cells (paraganglioma-like) and, (3) spindle cells (schwannoma-like). Symptoms and signs
The most common presentation is gastrointestinal bleed (~45% of cases), followed by abdominal pain (~43% of cases) and anemia (~15% of cases). Pathology
GP consist of three components (1) ganglion cells, (2) epithelioid cells (neuroendocrine-like), and (3) spindle cells (schwannoma-like). The microscopic differential diagnosis includes poorly differentiated carcinoma, neuroendocrine tumour and paraganglioma.GPs may be sporadic or arise in the context neurofibromatosis type 1. See also
Schwannoma
Paraganglioma


== References ==