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Amyotrophic lateral sclerosis
von Hippel-Lindau disease
Acoustic neuroma (schwannoma)
Adult brain tumors
Pediatric brain tumors
Transient ischemic attack
Cavernous sinus thrombosis
Spinocerebellar ataxia (NORD)
Tethered spinal cord syndrome
Lewy body dementia
Normal pressure hydrocephalus
Acute disseminated encephalomyelitis
Central pontine myelinolysis
JC virus (Progressive multifocal leukoencephalopathy)
Idiopathic intracranial hypertension
Opsoclonus myoclonus syndrome (NORD)
Restless legs syndrome
Early infantile epileptic encephalopathy (NORD)
Cauda equina syndrome
Treponema pallidum (Syphilis)
Vitamin B12 deficiency
Concussion and traumatic brain injury
Spinal muscular atrophy
Carpal tunnel syndrome
Thoracic outlet syndrome
Lambert-Eaton myasthenic syndrome
Adult brain tumors: Pathology review
Central nervous system infections: Pathology review
Cerebral vascular disease: Pathology review
Congenital neurological disorders: Pathology review
Dementia: Pathology review
Demyelinating disorders: Pathology review
Headaches: Pathology review
Movement disorders: Pathology review
Neurocutaneous disorders: Pathology review
Neuromuscular junction disorders: Pathology review
Pediatric brain tumors: Pathology review
Seizures: Pathology review
Spinal cord disorders: Pathology review
Traumatic brain injury: Pathology review
Normal Pressure Hydrocephalus
In normal pressure hydrocephalus, hydrocephalus can be broken down into “hydro” which means water and “cephalus” which means head.
Hydrocephalus, which is also termed as “water on the brain”, is an excessive buildup of cerebrospinal fluid within the brain.
Even though the pressure on lumbar puncture is expected to be increased, in this case, it’s normal, which is why it’s termed as “normal pressure” hydrocephalus.
Let's start with some relevant anatomy. The brain has four interconnected cavities in the brain called ventricles, and each one contains a structure called a choroid plexus.
The choroid plexus is made up of ependymal cells which produces cerebrospinal fluid - a fluid that helps provide buoyancy and protection, as well as metabolic fuel for the brain.
Highest up, are two C-shaped lateral ventricles that lie deep in each cerebral hemisphere.
The two lateral ventricles drain their cerebrospinal fluid into the third ventricle, which is a narrow, funnel-shaped, cavity at the center of the brain.
The third ventricle makes a bit more cerebrospinal fluid and then sends all of the cerebrospinal fluid to the fourth ventricle via the cerebral aqueduct.
The fourth ventricle is a tent-shaped cavity located between the brainstem and the cerebellum.
After the fourth ventricle, the cerebrospinal fluid enters the subarachnoid space, which is the space between the two inner linings of the brain - the arachnoid and pia mater.
Normal pressure hydrocephalus is a condition characterized by ventricular enlargement, without an increase in cerebrospinal fluid pressure on lumbar puncture. Cerebrospinal fluid (CSF) accumulates slowly and gradually in the ventricles, causing them to dilate. Ventricular dilation restores the CSF pressure to the normal level, hence the normal findings on lumbar puncture.
People with normal pressure hydrocephalus present with urinary incontinence, gait disturbances, and dementia. The excess amount of CSF can be temporarily drained through a lumbar puncture, but the long-term management is a surgical procedure called a ventriculoperitoneal shunt, in which a tube is inserted into one of the ventricles of the brain and directed to the abdomen, where the excess CSF can be absorbed.
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