Akademik

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.

- suboccipital d. d. of the posterior fossa by occipital craniectomy and opening of the dura.

- subtemporal d. d. of the brain by temporal craniectomy and opening of the dura over the inferolateral surface of the temporal lobe.

- trigeminal d. d. of the trigeminal nerve root.

de·com·pres·sion -'presh-ən n the act or process of releasing from pressure or compression: as

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 rapidly

b) 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)

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.