Subarachnoid Space: From 2 Different Sources
The space between the arachnoid and the pia mater – two of the membranes covering the BRAIN. (See also MENINGES.)
the space between the arachnoid and pia *meninges of the brain and spinal cord, containing circulating cerebrospinal fluid and large blood vessels. Several large spaces within it are known as cisternae.
A haemorrhage into the subarachnoid space in the BRAIN. It is usually the result of rupture of an ANEURYSM on the CIRCLE OF WILLIS. Head injury or intense physical exercise occasionally cause subarachnoid haemorrhage; the diagnosis is con?rmed by CT scan or by identifying blood in the CEREBROSPINAL FLUID at LUMBAR PUNCTURE. Cerebral ANGIOGRAPHY will usually pinpoint the site of bleeding. Treatment is bed rest, life-support measures and procedures to reduce blood pressure; sometimes surgery is carried out but not usually until several weeks after the acute episode. About 30 per cent of patients recover fully, whilst some have residual disabilities such as EPILEPSY, mental deterioration or paralysis. About 50 per cent of those affected die.... subarachnoid haemorrhage
A medical specialty dealing with the physiological, PSYCHOLOGICAL and pathological consequences of space ?ight in which the body has to cope with unusual variations in gravitational forces, including weightlessness, a constricted environment, prolonged close contact with work colleagues in very demanding technical circumstances, and sustained periods of emotional pressure including fear. Enormous progress has been made in providing astronauts with as normal an environment as possible, and they have to undergo prolonged physical and mental training before embarking on space travel.... space medicine
Gas exchange only occurs in the terminal parts of the pulmonary airways (see LUNGS). That portion of each breath that is taken into the lungs but does not take part in gas exchange is known as dead space. Anatomical dead space describes air in the airways up to the terminal BRONCHIOLES. Physiological dead space also includes gas in alveoli (air sacs) which are unable to take part in gas exchange because of structural abnormalities or disease.... dead space
The name given to the region behind the knee. The muscles attached to the bones immediately above and below the knee bound a diamond-shaped space through which pass the main artery and vein of the limb (known in this part of their course as the popliteal artery and vein); the tibial and common peroneal nerves (which continue the sciatic nerve from the thigh down to the leg); the external saphenous vein; and several small nerves and lymphatic vessels. The muscles – which bound the upper angle of the space and which are attached to the leg bones by strong prominent tendons – are known as the hamstrings. The lower angle of the space lies between the two heads of the gastrocnemius muscle, which makes up the main bulk of the calf of the leg.... popliteal space
see parapharyngeal space.... lateral parapharyngeal space
(lateral parapharyngeal space) the region at the side of the *pharynx. Infection in this space can result in a parapharyngeal abscess. It is also a site where tumours can develop.... parapharyngeal space
see Virchow–Robin spaces.... perivascular spaces
see nasopharynx.... postnasal space
the region between the posterior parietal *peritoneum and the front of the *lumbar vertebrae. It contains important structures, including the kidneys, adrenal glands, pancreas, lumbar spinal nerve roots, sympathetic ganglia and nerves, and the abdominal *aorta and its major branches.... retroperitoneal space
the region behind the *pharynx and in front of the bones of the neck. Infection in this space can result in a retropharyngeal abscess.... retropharyngeal space
a custom-made orthodontic appliance that maintains an existing space in the dentition to allow a permanent tooth to erupt into the space. It may be removable or cemented into place.... space maintainer
n. a plastic container with a mouthpiece at one end and a hole for an aerosol inhaler at the other. The dose from the inhaler is sprayed into the spacer, from which it can be inhaled without needing to coordinate breathing. It is particularly useful for babies and small children who do not have this coordination. Paediatric spacers also have a small mask that fits onto the mouthpiece of the spacer and is placed over the child’s nose and mouth. Spacers help to deliver a greater proportion of the dose to the airways while reducing the proportion absorbed into the body (which is the usual cause of unwanted side-effects)... spacer
(perivascular spaces) fluid-filled spaces that form around blood vessels in the *pia mater as they penetrate deeper brain tissue. They may dilate, resulting in raised intracranial pressure. [R. Virchow (1821–1902), German pathologist]... virchow–robin spaces
the soft tissue between the bases of the fingers and toes.... web space
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