Normal pressure

Normal Pressure Hydrocephalus (NPH) is a type of hydrocephalus that occurs in adults, typically in those over the age of 60. It is characterized by an abnormal increase of cerebrospinal fluid (CSF) in the brain's ventricles, or cavities, which can cause a triad of symptoms: gait disturbance, dementia, and urinary incontinence.

Etiology

The exact cause of NPH is often unknown. However, it can sometimes be traced to a known cause such as subarachnoid hemorrhage, head trauma, meningitis, or brain tumor. These conditions can block the normal flow of CSF, leading to its accumulation in the ventricles.

Symptoms

The classic symptom triad of NPH includes gait disturbance, dementia, and urinary incontinence. Gait disturbance is often the first symptom to appear, characterized by a broad-based, shuffling walk. Dementia in NPH is usually of the subcortical type, with symptoms such as forgetfulness, slow mental processing, and difficulty focusing attention. Urinary incontinence is typically a later symptom and may be accompanied by a sense of urgency or frequency.

Diagnosis

Diagnosis of NPH involves a clinical evaluation, imaging studies such as MRI or CT scan, and sometimes a lumbar puncture or CSF shunt trial. The Evans' index, a ratio of the maximum width of the frontal horns of the lateral ventricles to the maximum width of the inner table of the cranium, is often used as a radiological marker in the diagnosis of NPH.

Treatment

The primary treatment for NPH is the surgical insertion of a shunt to drain excess CSF from the brain to another part of the body where it can be absorbed. This procedure, known as ventriculoperitoneal shunting, can significantly improve symptoms in many patients.

Prognosis

With early diagnosis and treatment, the prognosis for NPH can be good. However, if left untreated, the condition can lead to serious complications such as severe dementia and physical disability.