Search results
Results from the WOW.Com Content Network
Intracranial hypertension (IH), also called increased ICP (IICP) or raised intracranial pressure (RICP), refers to elevated pressure in the cranium. 20–25 mmHg is the upper limit of normal at which treatment is necessary, though it is common to use 15 mmHg as the threshold for beginning treatment.
In place of the stethoscope, a Doppler ultrasound beam measures the blood flow pulsations in intracranial and extracranial segments of the ophthalmic artery. The non-invasive ICP meter based on this method gradually increases the pressure over the eyeball and intraorbital tissues so that the blood flow pulsation parameters in two sections of ...
Idiopathic intracranial hypertension (IIH), previously known as pseudotumor cerebri and benign intracranial hypertension, is a condition characterized by increased intracranial pressure (pressure around the brain) without a detectable cause. [2] The main symptoms are headache, vision problems, ringing in the ears, and shoulder pain.
Under normal conditions, regular movements such as leaning forward, normal heartbeat and breathing can cause changes to the ICP. Intracranial monitoring accounts for this by averaging measurements over 30 minutes in non-comatose patients. Readings between 7-15mmHg are considered normal in an adult, 3-7mmHg in children, and 1.4-6mmHg in infants. [4]
Cerebral perfusion pressure (CPP) is defined as the mean arterial pressure (MAP) minus the intracranial pressure (ICP). In normal individuals, it should be above 50 mm Hg. Intracranial pressure should not be above 15 mm Hg (ICP of 20 mm Hg is considered as intracranial hypertension). [14]
Spaceflight associated neuro-ocular syndrome (SANS), [1] previously called spaceflight-induced visual impairment, [2] is hypothesized to be a result of increased intracranial pressure (ICP), although experiments directly measuring ICP in parabolic flight have shown ICP to be in normal physiological ranges during acute weightless exposure. [3]
Raised intracranial pressure [1] as a result of one or more of the following: Brain tumor, idiopathic intracranial hypertension (also known as Pseudotumor Cerebri), cerebral venous sinus thrombosis or intracerebral hemorrhage; Respiratory failure [4] Isotretinoin, which is a powerful derivative of vitamin A, rarely causes papilledema.
An alternative definition of CPP is: [1] = where: MAP is mean arterial pressure ICP is intracranial pressure JVP is jugular venous pressure. This definition may be more appropriate if considering the circulatory system in the brain as a Starling resistor, where an external pressure (in this case, the intracranial pressure) causes decreased blood flow through the vessels.