urogenital diaphragm

(redirected from diaphragma urogenitale)
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diaphragm

 [di´ah-fram]
1. the musculomembranous partition separating the thoracic and abdominal cavities. On its sides it is attached to the six lower ribs, at its front to the sternum, and at its back to the spine. The esophagus, aorta, vena cava, and numerous nerves pass through the diaphragm. When relaxed it is convex, but it flattens as it contracts during inhalation, thereby enlarging the chest cavity and allowing for expansion of the lungs. See also respiration.
2. any separating membrane or structure.
3. a disk with one or more openings or with an adjustable opening, mounted in relation to a lens or source of radiation, by which part of the light or radiation may be excluded from the area.
contraceptive diaphragm a shallow dome-shaped disk used as a contraceptive, made of a soft plastic material such as latex. Its anterior lip fits behind the symphysis pubis and its posterior lip rests in the posterior fornix. It is used with a spermicide to prevent entrance of spermatozoa into the cervical os. See also contraception.
pelvic diaphragm the portion of the floor of the pelvis formed by the coccygeus muscles and the levator ani muscles, and their fascia.
polyarcuate diaphragm one showing abnormal scalloping of margins on radiographic visualization.
urogenital diaphragm a traditional but no longer valid concept that superior and inferior layers enclose the sphincter urethrae and deep transverse perineal muscles and together form a musculomembranous sheet that extends between the ischiopubic rami.
vaginal diaphragm contraceptive diaphragm.

ur·o·gen·i·tal di·a·phragm

an obsolete concept of a trilaminar, triangular sheet of muscle and fascia spanning the ischiopubic rami; composed of the sphincter urethrae and the deep transverse perineal muscles (which were said to be flat muscles forming a continuous sheet), plus the perineal membrane below and a superior fascia of the diaphragm above. Evidence of the latter is lacking. The muscle-containing space between the fascial structures was formerly referred to as the deep perineal space. The terms urogenital diaphragm and deep perineal space are not recognized by Terminologia Anatomica due to more accurate understanding of the morphology, especially of the sphincter urethrae.

u·ro·gen·i·tal di·a·phragm

(yūr'ō-jen'i-tăl dī'ă-fram)
A triangular sheet of muscle between the ischiopubic rami; composed of the sphincter urethrae and the deep transverse perineal muscles.

diaphragm

1. the musculomembranous partition separating the thoracic and abdominal cavities. On its sides, it is attached to the caudal ribs; ventrally to the sternum; at the back, to the spine. The esophagus, the aorta and vena cava, and nerves pass through the diaphragm. When relaxed, the diaphragm is convex but it flattens and moves caudally as it contracts during inhalation, thereby enlarging the chest cavity and allowing for expansion of the lungs. See also respiration.
2. any separating membrane or structure.
3. a disk with one or more openings or with an adjustable opening, mounted in relation to a lens, by which part of the light may be excluded from the area.
See also diaphragmatic.

Potter-Bucky diaphragm
see Potter-Bucky grid.
lightbeam diaphragm
an adjustable diaphragm which is used to cone down a light beam that indicates the dimensions of an x-ray beam and marks the position of the central ray.
pelvic diaphragm
the portion of the caudal wall of the pelvis formed by the coccygeus muscles, the levator ani muscles and fascia.
slit diaphragm
see filtration membrane.
urogenital diaphragm
the musculomembranous layer superficial to the pelvic diaphragm, extending between the ischiopubic rami and surrounding the urogenital ducts.