Differential Diagnosis Of Normal Pressure Hydrocephalus (NPH)

       Noncontrast CT demonstrates enlarged lateral ventricles without significant cerebral atrophy

Normal Pressure Hydrocephalus (NPH) can be idiopathic or secondary to meningitis, subarachnoid hemorrhage, or head trauma, and is caused by impaired reabsorption of spinal fluid. Patients present with gait abnormalities, urinary
incontinence, and/or cognitive impairment. Diagnosis is confirmed by radiographic evidence and a normal opening pressure on lumbar puncture.

Differential Diagnosis:
• Alzheimer disease—Impaired orientation and memory, which are often spared in NPH; cortical atrophy.

A Case Of Normal-pressure hydrocephalus

A 75-year-old man is brought in to your office by his wife. She complains that he is not the same over the last 6 months. His memory is failing him, he has difficulty walking (especially when he initiates walking), and he is incontinent of urine. Which of the following is the most likely diagnosis based on his history?

Answer: Normal-pressure hydrocephalus (NPH)

Discussion:  Normal-pressure hydrocephalus(NPH) is a cause of dementia in the elderly. It may be
caused by previous insult to the brain, usually as a result of a subarachnoid hemorrhage or diffuse meningitis that presumably results in scarring of the arachnoid villi over the brain convexities where cerebrospinal fluid (CSF) absorption usually occurs. However, elderly NPH patients seldom have a
history of predisposing disease.

NPH classically consists of

• dementia,
• apraxia of gait, and 
• incontinence 

A 2 Month Old Baby Is Hospitalized With Hydrocephalus Since Birth

A 2 month old baby who was diagnosed as a case of hydrocephalus on a prenatal ultrasound is hospitalized since birth and is under the care of pediatricians and neurosurgeons. The baby has an enlarged head circumference above 95 percentile and has difficulty feeding and has had 3 episodes of seizures. There is no active infection and there is plan for surgically inserting a shunt system.
The picture of the patient is shown below;

The eyes show the sun-set sign characteristic of hydrocephalus in babies.

Case Discussion:
Hydrocephalus is derived for the Greek words: Hydro means water and cephalus means head. It is a condition that is characterized by excessive accumulation of fluid in the brain. Since in young babies the skull sutures ares till open, the excess fluid leads to rapid enlargement of the head.

Physiology:  Cerebrospinal fluid (CSF)is an essential component of the nervous system that circulates through a system of passageways known as ventricles in the brain and exists through a reservoir known as cistern. CSF provides nutrients to the brain and takes away the waste products. If there is a blockage at any of these passages the fluid starts to accumulate leading to hydrocephalus. Sometimes there is no blockage but there is excess production of fluid and inadequate absorption leading to accumulation.