Loading...



  • mmHg
  • Ophthalmic artery (OA) - a unique vessel with intracranial and extracranial segments is used as pressure sensor and as a natural pair of scales for absolute ICP value in mmHg or mmH2O measurement. (wikipedia.org)
  • The body has various mechanisms by which it keeps the ICP stable, with CSF pressures varying by about 1 mmHg in normal adults through shifts in production and absorption of CSF. (wn.com)
  • As a rule, patients with normal blood pressure retain normal alertness with ICP of 25-40 mmHg (unless tissue shifts at the same time). (wikipedia.org)
  • Acute
  • This device and technique may be used to study the role of ICP pulsatility in intracranial hemo- and hydrodynamic processes and introduces the creation of a potential platform of a cardiac-gated system for treatment of acute and chronic low blood flow states, and diseases requiring augmentation of CSF substance clearance or delivery. (diva-portal.org)
  • vessel
  • [ 19 ] He drained dogs of their blood and was able to observe that the brain remained comparatively well perfused until shortly before death regardless of the dog's position in space (hanging upside down or right side up, to control for the effects of gravity), unless the blood was drained from an intracranial vessel directly, in which case death resulted almost immediately. (medscape.com)
  • High intracranial pressure means that both nervous system and blood vessel tissues are under pressure. (floridahealthfinder.gov)
  • hydrocephalus
  • This increase of intracranial pressure (ICP) may be caused by a congenital or acquired pathology (i.e. the hydrocephalus) as well as by the increasing volume of a cranial mass lesion, among others. (upc.edu)
  • arterial
  • Direct comparison of arterial blood pressure (ABP) and externally applied pressure is the basic arterial blood pressure measurement principle which eliminates the need of individual calibration. (wikipedia.org)
  • CSF pressure has been shown to be influenced by abrupt changes in intrathoracic pressure during coughing (intraabdominal pressure), valsalva maneuver , and communication with the vasculature ( venous and arterial systems). (wn.com)
  • tissues
  • Blood flow in the intracranial OA segment is affected by intracranial pressure, while flow in the extracranial (intraorbital) OA segment is influenced by the externally applied pressure (Pe) to the eyeball and orbital tissues. (wikipedia.org)
  • As with a sphygmomanometer, a special pressure cuff is used - in this case to compress the tissues surrounding the eyeball and also intraorbital tissues surrounding the extracranial segment of OA. (wikipedia.org)
  • nervous system
  • Hyperactivity of the sympathetic nervous system can manifest as increased heart rate, increased respiration, increased blood pressure, diaphoresis, and hyperthermia. (wikipedia.org)
  • compliance
  • The concept of ICP (normal or abnormal) being a function of the volume and compliance of each component of the intracranial compartment was proposed by the Scottish anatomist and surgeon Alexander Monro (1733-1817) and his student George Kellie (1758-1829) during the late 18th century. (medscape.com)
  • cause
  • Even more obscure diseases such as intracranial tuberculoma have been seen to cause onset of paroxysmal sympathetic hyperactivity. (wikipedia.org)
  • contrast
  • In contrast to molsidomine, this was accompanied by significant decrease in systolic peripheral blood pressure. (springer.com)
  • These adaptations to rapid changes in blood pressure (in contrast with changes that occur over periods of hours or days) are known as dynamic cerebral autoregulation. (wikipedia.org)
  • stable
  • Although the classic 'autoregulation curve' suggests that CBF is fully stable between these blood pressure values (known also as the limits of autoregulation), CBF may vary as much as 10% below and above its average within this range. (wikipedia.org)
  • systemic
  • Early studies suggested that baroreflexes dilate or have no effect, but recent studies in awake dogs suggested baroreflexes did not normally engage tonic vasoconstrictor efferents but during excitement systemic pressure rises may also trigger local sensory-motor dilator reflexes. (biomedsearch.com)
  • column
  • The fluid column pressure must be greater than the weight of the CSF in the system before drainage occurs. (wikipedia.org)
  • It may be defined as the pressure exerted by a column of water of 1 cm in height at 4 °C (temperature of maximum density) at the standard acceleration of gravity, so that 1 cmH2O (4°C) = 999.9720 kg/m3 × 9.80665 m/s2 × 1 cm = 98.063754138 Pa ≈ 98.0638 Pa, but conventionally a nominal maximum water density of 1000 kg/m³ is used, giving 98.0665 Pa. (wikipedia.org)
  • values
  • Although the classic 'autoregulation curve' suggests that CBF is fully stable between these blood pressure values (known also as the limits of autoregulation), CBF may vary as much as 10% below and above its average within this range. (wikipedia.org)
  • height
  • The EVD is set to drain into a closed, graduated burette at a height corresponding to a particular pressure level, as prescribed by a healthcare professional, usually a neurosurgeon or neurointensivist. (wikipedia.org)