Question

What is the role of intracranial pressure (ICP) in the pathophysiology of Hydrocephalus?

Answer 1

Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and, at rest, is normally 7–15 mmHg for a supine adult.

Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull.

The increase in intracranial pressure is a life threatening problem as it can damage the brain and spinal cord, one of the common cause of increasing icp is hydrocephalus.  

Intra cranial pressure increases when production of cerebrospinal fluid exceed absorption. It occurswhen CSF is produced more, increased resistance to csf flow and decreased resorption or increased venous sinus pressure.
When ICP rises CSF production falls. Compensation may occur by transventricular absorption of cerebrospinal fluid and also by absorption along nerve roots, which causes enlarged optic nerve sheaths. Firstly, the temporal and frontal horns dilates often asymmetrically. It can be result in the elevation of the corpus callosum, perforation of the septum pellucidum, thinning of the cerebral mantle or enlargement of the third ventricle downward into the pituitary fossa.

The elevated ICP may cause compression of the brain can lead to a damage of brain and other complications. There is a possible complication of hearing loss due to ICP. The mechanism of ICP on hearing loss is assumed that the transmission of CSF pressure to and from the Perilymphatic space through a patent cochlear aqueduct.