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(vas″kyŭ-lō-jen′ĕ-sĭs) [L. vasculum, a small vessel + genesis] Development of the vascular system.


(vas″kyŭ-lō-mōt′ŏr) Vasomotor.


(vas″kyŭ-lop′ă-thē) [L. vasculum, small vessel + -pathy] Any disease affecting blood vessels.

idiopathic polypoidal choroidal v. Hemorrhage from the choroidal blood vessels near the macula of the retina. It produces acute, painless, unilateral visual loss.

transplant v. Obstruction to blood flow through the vessels of a transplanted organ. On pathological examination of involved vessels, the intima is globally thickened, and infiltrated by fibroblasts, mononuclear cells, and smooth muscle cells. It is one cause of transplant failure.


(vă-sek′tŏ-mē) [vas + -ectomy] Removal of all or a segment of the vas deferens. Bilateral vasectomy is the most successful method of male contraception. The procedure prevents sperm (which are manufactured in the testicles) from being expelled in the male ejaculate. It is usually carried out as an outpatient or same day procedure under local or light intravenous anesthesia. SEE: illus.





NOTE: Persons who have had this surgical procedure ejaculate in a normal manner but the ejaculate contains semen, produced independently in the seminal vesicles, without sperm.

PATIENT CARE: Postoperatively, the patient applies cold packs to the surgical site, to limit swelling, pain, and inflammation. Activities are limited, sexual activity is avoided for a week. An athletic supporter or tightly fitting underwear are worn to support the scrotum and limit pain. The procedure is considered successful when two consecutive sperm samples are shown to be free of sperm, typically 8 to 12 weeks postoperatively. Men choose vasectomy only when they want to become permanently sterile. Nonetheless, the procedure can be reversed, although vasectomy reversal is a more complicated operation than the initial severing of the tubes.

image Patients should be advised that vasectomy does not prevent sexually transmitted diseases.

vasectomy reversal

Surgery to rejoin the previously severed vas deferens. Although this procedure may be successful, the chance of success varies in published reports.


(vas′ĭ-form″) [vas + -form] Resembling a tubular structure or vas.


(vă-sīt′ĭs) [vas + -itis] Inflammation of the ductus deferens of the testicle.

vaso-, vas-, vasi-

[L. vas, vessel] Prefixes meaning channel, vessel, blood vessel.


(vā″zō-ak′tiv) [vaso- + active] Affecting blood vessels.

vasoactive intestinal polypeptide

ABBR: ...

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