Hydrocephalus surgery
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Hydrocephalus Microchapters |
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Diagnosis |
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Treatment |
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Case Studies |
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Hydrocephalus surgery On the Web |
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American Roentgen Ray Society Images of Hydrocephalus surgery |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: Cafer Zorkun M.D., PhD.,Kalsang Dolma, MBBS
Overview
Surgery
Hydrocephalus treatment is surgical. It involves the placement of a ventricular catheter (a tube made of silastic), into the cerebral ventricles to bypass the flow obstruction/malfunctioning arachnoidal granulations and drain the excess fluid into other body cavities, from where it can be resorbed. Most shunts drain the fluid into the peritoneal cavity (ventriculo-peritoneal shunt), but alternative sites include the right atrium (ventriculo-atrial shunt), pleural cavity (ventriculo-pleural shunt), and gallbladder. A shunt system can also be placed in the lumbar space of the spine and have the CSF redirected to the peritoneal cavity (LP Shunt). An alternative treatment for obstructive hydrocephalus in selected patients is the endoscopic third ventriculostomy (ETV), whereby a surgically created opening in the floor of the third ventricle allows the CSF to flow directly to the basal cisterns, thereby shortcutting any obstruction, as in aqueductal stenosis. This may or may not be appropriate based on individual anatomy. Internal hydrocephalus can be successfully treated by placing a drainage tube (shunt) between the brain ventricles and abdominal cavity to eliminate the high internal pressures. There is some risk of infection being introduced into the brain through these shunts, however, and the shunts must be replaced as the person grows. A subarachnoid hemorrhage may block the return of CSF to the circulation. If CSF accumulates in the subarachnoid space, the condition is called external hydrocephalus. In this condition, pressure is applied to the brain externally, compressing neural tissues and causing brain damage. Thus resulting to a much further damage of the brain tissue and leading to necrotization
Shunt complications
Examples of possible complications include shunt malfunction, shunt failure, and shunt infection. Although a shunt generally works well, it may stop working if it disconnects, becomes blocked, or it is outgrown. If this happens the cerebrospinal fluid will begin to accumulate again and a number of physical symptoms will develop, some extremely serious, like seizures. The shunt failure rate is also relatively high and it is not uncommon for patients to have multiple shunt revisions within their lifetime.
The diagnosis of cerebrospinal fluid buildup is complex and requires specialist expertise.
Another complication can occur when CSF drains more rapidly than it is produced by the choroid plexus, causing symptoms - listlessness, severe headaches, irritability, light sensitivity, sound sensitivity, nausea, vomiting, dizziness, vertigo, migraines, seizures, a change in personality, weakness in the arms or legs, excessive head growth (seen infants, children under age 2), strabismus, and double vision - to appear when the patient is vertical. If the patient lies down, the symptoms usually vanish in a short amount of time. A CT scan may or may not show any change in ventricle size, particularly if the patient has a history of slit-like ventricles. Difficulty in diagnosing overdrainage can make treatment of this complication particularly frustrating for patients and their families.
Resistance to traditional analgesic pharmacological therapy may also be sign of shunt overdrainage or failure. Diagnosis of the particular complication usually depends on when the symptoms appear.