Normal Pressure Hydrocephalus
This article provides an in-depth exploration of Normal Pressure Hydrocephalus (NPH), a condition characterized by enlarged ventricular size with normal cerebrospinal fluid pressure. It differentiates NPH from non-communicating hydrocephalus and describes its classic clinical triad: dementia, urinary incontinence, and gait disturbance. The article covers diagnostic approaches, including MRI and CSF drainage tests, and discusses treatment options, primarily focusing on ventricular shunting. It also highlights potential complications associated with shunt procedures.
2023-12-31 17:51:38 - Editor
Understanding Normal Pressure Hydrocephalus
Normal pressure hydrocephalus (NPH) is the condition when ventricular size is pathologically enlarged with normal opening pressure of the cerebrospinal fluid (CSF). NPH is a form of communicating hydrocephalus and is distinguished from non-communicating hydrocephalus. Clinically, NPH is associated with a classic triad of dementia, urinary incontinence, and gait disturbance. NPH should be suspected in elderly patients presenting with unexplained, symmetric gait disturbance.
Cognitive Impairment and Diagnostic Approaches in NPH
Cognitive impairment in NPH evolves over months to years and usually develops after the onset of gait dysfunction. Patients typically have both subcortical and frontal features. MRI brain usually shows ventriculomegaly out of proportion to sulcal enlargement. An alternative diagnostic approach is with continuous CSF drainage via a temporary catheter in the lumbar CSF space.
Treatment for Normal Pressure Hydrocephalus
The treatment for NPH is with ventricular shunting, which diverts the CSF from the brain into either the peritoneum (ventriculoperitoneal) or the heart (ventriculoatrial). However, patients with moderate to severe dementia are unlikely to improve after shunting.
Complications Associated with Shunt Procedures
Shunt overdrainage is the most common complication in the first year, occurring in up to one-third of patients. Other reported side effects include hemorrhage, infection, abdominal injury, and/or arrhythmia.
References
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