| Topic: | NDI: An Overview |
|---|---|
| Author: | Robertson, Gary |
Nephrogenic diabetes insipidus.
An excessive amount of cerebrospinal fluid, usually under increased pressure, within the skull. The term "water on the brain" is sometimes used to describe the condition. Hydrocephalus is often associated with other congenital abnormalities, particularly spina bifida .
Causes
The condition may be congenital (present at birth) or may develop as a result of major head injury, brain hemorrhage, infection (meningitis, for example), or a tumor.
Hydrocephalus is caused by excessive formation of cerebrospinal fluid, by a block in the circulation of this fluid, or both.
Symptoms
When the condition is congenital, the main feature is an enlarged head that continues to grow at an abnormally fast rate because the bones are not rigid and expand to accommodate the fluid. Other features are rigidity of the legs, epilepsy, irritability, lethargy, vomiting, and the absence of normal reflex actions. If the condition is not treated, it progresses to extreme drowsiness, severe brain damage, and seizures, which may lead to the baby's death within a matter of weeks.
When the condition occurs later in childhood or in adulthood, the skull is no longer flexible and symptoms are caused by raised pressure within the skull. Symptoms include headache, vomiting, loss of coordination, and deterioration of mental function.
Diagnosis and Treatment
CT scanning or MRI show the location and nature of any obstruction.
In most cases, treatment aims to drain excess fluid away from the brain to another part of the body, such as the lining of the abdomen or chest wall, where it can be absorbed. Draining is achieved by means of a shunt (tube), which is inserted into the brain through a hole made in the skull. In some cases, the shunt must be left in position indefinitely. In older children and adults, treatment is sometimes for the underlying cause only.
Nephrogenic diabetes insipidus.
Distention of the pelvis and calices of the kidney with urine, as a result of obstruction of the ureter.
One of a pair of vertebrate organs situated in the body cavity near the spinal column that excrete waste products of metabolism, in man are bean-shaped organs about 4-1/2 inches long lying behind the peritoneum in a mass of fatty tissue, and consist chiefly of nephrons by which urine is secreted, collected, and discharged into a main cavity whence it is conveyed by the ureter to the bladder.