Atlas of Human Anatomy by Netter

FACTS & HINTS

High-Yield Facts

Clinical Points

Meningitis

Inflammation of the arachnoid and pia mater

Can be caused by drugs or malignancy, but usually by pathogenic bacteria

Infection can be due to meningococcal or pneumococcal bacteria

Patient may present with fever, nonblanching purpuric rash, neck stiffness, and photophobia

Mortality from bacterial causes can be up to 30%

Diagnosis is by examination and lumbar puncture

Hydrocephalus

Caused by excess cerebrospinal fluid (CSF) production or, more likely, by abnormal absorption

Classified as obstructive, communicating or normal pressure

Blockage usually in cerebral aqueduct by narrowing

Can be a result of tumor, hemorrhage, and infection

Communicating blocks movement of CSF from ventricles

Can be caused by absence of arachnoid granulations or subarachnoid hemorrhage

Dilates ventricles, thins cerebral cortex, separates bones of calvaria in infants

Brain tumors

Twenty-five percent of all brain tumors arise from a different site (metastasis)

Common sites of original tumor include: breast, bronchus, prostate, thyroid, and kidney

Primary brain tumors can be benign, such as meningiomas and neurofibromas, or malignant, such as astrocytomas and

oligodendrogliomas

Can present as epilepsy, focal neurology, or signs of raised intracranial pressure

Diagnosis is by history, examination, and computed tomography (CT) or magnetic resonance imaging (MRI) of the brain