- Removal of pressure. [L. de-, from, down, + com-primo, pp. -pressus, to press together]- cardiac d. incision into the pericardium or aspiration of fluid from the pericardium to relieve pressure due to blood or other fluid in the pericardial sac. SYN: pericardial d..- cerebral d. removal of a piece of the cranium, with incision of the dura, to relieve intracranial pressure.- explosive d. SYN: rapid d..- internal d. removal of intracranial tissue, usually tumor, hematoma, or brain tissue; to relieve pressure.- nerve d. release of pressure on a nerve trunk by the surgical excision of constricting bands or widening of a bony canal.- optic nerve sheath d. a venting of the optic nerve sheath into the retrobulbar space, by slitting or by fenestrating the sheath. See optic nerve sheath fenestration.- orbital d. removal of a portion of the bony orbit, usually superior (Naffziger operation), lateral (Krönlein operation), or inferior (Ogura operation).- pericardial d. SYN: cardiac d..- rapid d. sudden severe expansion of gases due to a reduction in ambient pressure. SYN: explosive d..- spinal d. the removal of pressure upon the spinal cord as created by a tumor, cyst, hematoma, herniated nucleus pulposus, abscess, or bone.- subtemporal d. d. of the brain by temporal craniectomy and opening of the dura over the inferolateral surface of the temporal lobe.
* * *a) reduction of pressure: (1) the decrease of ambient air pressure experienced in an air lock on return to atmospheric pressure after a period of breathing compressed air (as in a diving bell or caisson) or experienced in ascent to a great altitude without a pressure suit or pressurized cabin (2) the decrease of water pressure experienced by a diver when ascending rapidlyb) an operation or technique used to relieve pressure upon an organ (as in fractures of the skull or spine) or within a hollow organ (as in intestinal obstruction)
* * *n.1. the reduction of pressure on an organ or part of the body by surgical intervention. Surgical decompression can be effected at many sites: the pressure of tissues on a nerve may be relieved by incision; raised pressure in the fluid of the brain can be lowered by cutting into the dura mater; and cardiac compression - the abnormal presence of blood or fluid round the heart - can be cured by cutting the sac (pericardium) enclosing the heart.2. the gradual reduction of atmospheric pressure for deep-sea divers, who work at artificially high pressures. See compressed air illness.
* * *de·com·pres·sion (de″kom-preshґən) 1. any removal of pressure. 2. the lessening of atmospheric pressure on deep-sea divers and caisson workers who return to normal pressure environments, or on persons ascending to great heights. If not controlled or artificially slowed, it can cause decompression sickness. 3. any technique for artificially controlling this process. 4. a surgical operation for the relief of pressure in a body compartment.
Medical dictionary. 2011.