Within the brain, cavities called ventricles house cerebrospinal fluid. Ideally this fluid stays at a constant level and flows between the central canal of the spinal chord and the ventricles of the brain. Certain conditions upset this level and cause serious and sometimes deadly consequences. Dorland’s Illustrated Medical Dictionary, 31st ed., classifies these conditions according to how the excess fluid, a condition known as hydrocephalus, originated. In general, hydrocephalus causes both transient and permanent neurological problems.
Acquired
Meningitis, an inflammation of the layers of the brain’s covering, affects the cerebral fluid level and often leads to a hydrocephalic state. According to Current Medical Diagnosis and Treatment, 2010, both viral and bacterial meningitis require immediate care. Nearly all cases of meningitis produce fever, headache, stiff neck and altered mental state.
Congenital
Hydrocephalus develops from the congenital malformation of the brain’s ventricles. A child born with this condition usually displays an oversized frontal skull. This serious congenital condition occurs before the closing of the skull before birth. The deformed pathways cause obstructions to the fluid and result in chronic accumulation leading to mental retardation, an undersized brain and convulsions.
Communicating
Also known as non-obstructive hydrocephalus, in this form cerebrospinal fluid builds up because the body is unable to rebsorb the fluid back into the venous system. Other diseases or conditions contribute to this deficit.
Obstructive
A brain with normally formed canals and ventricles develops an obstruction such as a tumor. Any space occupying lesion hinders the normal flow of fluid between the brain and the spinal cord. Symptoms include headaches, imbalance and incontinence. These same symptoms appear in the elderly as their ability to absorb spinal fluid lessens.
Posthemorrhagic
An infant who experiences a hemorrhage in the brain acquires distended ventricles. The resulting obstruction and hydrocephalic state often resolve spontaneously with no permanent damage. When it fails to resolve the condition leads to permanent neurological deficits.
An adult who hemorrhages in the brain from an aneurysm (weakened blood vessel wall that bulges). As the aneurysm grows it puts pressure on the surrounding structures, which upsets the fluid balance. Warning signs appear if the aneurysm leaks before rupturing. These signs may include headaches, nausea and stiff neck. A complete rupture causes bleeding in the brain and the state of hydrocephalus.
References
- Dorland's Illustrated Medical Dictionary 31st. ed.; Saunders Elsevier, pub.; 2007
- Current Medical Diagnosis and Treatment 49th. ed.; Stephen J. McPhee and Maxine A. Papadakis; 2010
