Study Guide Overview

What is a traumatic brain injury (TBI)?

An alteration in brain function or evidence of brain pathology caused by an external force

What is a primary brain injury?

Direct injury caused by the initial trauma

What is a secondary brain injury?

Indirect injury caused by cellular and molecular changes and systemic responses after the initial trauma

What is a focal brain injury?

An injury that affects one area of the brain

What is a diffuse brain injury?

An injury that affects multiple areas of the brain

What is diffuse axonal injury (DAI)?

Widespread damage caused by shearing or stretching of axons

What causes diffuse axonal injury?

Rotational forces | twisting movements | acceleration-deceleration forces

What is a coup injury?

Brain injury at the site of impact

What is a contrecoup injury?

Brain injury on the opposite side of the skull when the brain rebounds

How is a concussion different from a contusion?

Concussion is a traumatic disturbance of brain function | contusion is bruising of brain tissue

What is a mild concussion according to the slides?

Temporary axonal disturbances causing attention and memory deficits without loss of consciousness

What is an epidural hematoma?

A collection of blood between the skull and dura commonly caused by injury to the middle meningeal artery or vein

What is a lucid interval in an epidural hematoma?

A period of apparent recovery after initial loss of consciousness followed by worsening symptoms

Why is an epidural hematoma a medical emergency?

Bleeding can increase intracranial pressure and cause worsening neurological function

What is spinal shock?

Temporary loss of reflex function below a spinal cord lesion

What are manifestations of spinal shock?

Flaccid paralysis | sensory deficits | loss of bladder and rectal control

What is neurogenic shock?

Loss of sympathetic activity after a high spinal cord injury causing cardiovascular instability

What is autonomic dysreflexia?

A sudden excessive sympathetic reflex causing dangerously high blood pressure after a high spinal cord injury

What spinal cord injury level is associated with autonomic dysreflexia?

T6 or above

What commonly triggers autonomic dysreflexia?

A full bladder | bowel impaction | other sensory stimulation below the lesion

What are manifestations of autonomic dysreflexia?

Severe hypertension | bradycardia | pounding headache | blurred vision | sweating | flushing | goosebumps | nasal congestion | nausea

What is the first intervention for autonomic dysreflexia?

Elevate the head of the bed and sit the person upright

What is degenerative disk disease?

Wear and deterioration of intervertebral disks

What is spondylolysis?

A defect or degenerative process involving a vertebral structure

What is spondylolisthesis?

Forward slipping of one vertebra in relation to the vertebra below

What is spinal stenosis?

Narrowing of the spinal canal

What is a herniated intervertebral disk?

Displacement of disk material beyond the disk space that can compress a nerve root

What is sciatica?

Pain radiating along the sciatic nerve often due to nerve root compression

What is epilepsy?

A disorder characterized by a tendency to have recurrent unprovoked seizures

What is an epileptogenic focus?

An area of the brain where abnormal electrical activity begins and can trigger seizures

What is a focal seizure?

A seizure that begins in one specific region of the brain

What is a generalized seizure?

A seizure that involves both sides of the brain from its onset

What is a cerebrovascular disorder?

An abnormality of the brain caused by a pathological process in blood vessels

What are the two major types of cerebrovascular abnormalities?

Ischemia with or without infarction | hemorrhage

What is an ischemic stroke?

A stroke caused by blocked blood flow to part of the brain

What is a hemorrhagic stroke?

A stroke caused by bleeding into or around the brain

What is a cryptogenic stroke?

A stroke whose cause remains undetermined

What is a transient ischemic attack (TIA)?

Temporary neurological dysfunction caused by reduced blood flow without acute infarction

Why do TIA symptoms resolve completely?

Blood flow returns before permanent brain tissue injury occurs

What is a thrombotic stroke?

A stroke caused by a clot forming in an artery supplying the brain

What is an embolic stroke?

A stroke caused by a clot or fragment traveling from elsewhere and blocking a brain artery

What is a lacunar stroke?

A small infarction caused by occlusion of a small penetrating artery

What is cellular edema during an ischemic stroke?

Cell swelling that can compress capillaries and worsen blood flow

What is the greatest stroke risk factor listed in the slides?

Hypertension

What is an intracranial aneurysm?

A weak bulging area of an arterial vessel wall

What is an arteriovenous malformation (AVM)?

An abnormal tangle of vessels where arteries connect directly to veins

How is an AVM different from an aneurysm?

An AVM is an abnormal artery-to-vein connection | an aneurysm is a weak bulging area of an artery wall

What is a subarachnoid hemorrhage?

Bleeding into the subarachnoid space that can cause inflammation and meningeal irritation

What is a major warning symptom of a ruptured cerebral aneurysm?

A sudden explosive or thunderclap headache

How does a migraine differ from a cluster headache?

Migraine often lasts 4–72 hours and may include nausea or light sensitivity | cluster headache causes intense unilateral attacks often around one eye

What is an aura in migraine?

A temporary neurological symptom that can occur before or during a migraine

What are common migraine symptoms?

Unilateral pain | pulsating pain | worsening with activity | nausea | photophobia | phonophobia

What are common cluster headache manifestations?

Severe unilateral pain | tearing | drooping eyelid | nasal congestion | pain around the eye or midface

What is a tension-type headache?

A mild-to-moderate bilateral headache that feels like a tight band or pressure

What is meningitis?

Inflammation of the meninges surrounding the brain and spinal cord

How can infections enter the central nervous system?

Hematogenous spread through blood | direct extension from another infection site

What is pyogenic infection?

An infection that produces pus

What are common signs of CNS infection?

Fever | head or spinal pain | generalized or focal neurological dysfunction

What are common manifestations of bacterial meningitis?

Worsening headache | photophobia | nuchal rigidity | vomiting | positive Kernig or Brudzinski signs

How does viral meningitis usually differ from bacterial meningitis?

Viral meningitis is generally milder and causes headache | mild photophobia | neck stiffness | fever | malaise

Why is viral meningitis also called aseptic meningitis?

Routine bacterial cultures usually do not identify a bacterial cause

How can fungi and mycobacteria reach the CNS and cause meningitis?

They can spread through the blood or extend directly from another infection site

What is a brain or spinal cord abscess?

A localized collection of pus within or around CNS structures

What is a peripheral neuropathy?

Damage or dysfunction affecting peripheral nerves

What is distal axonal polyneuropathy?

Damage affecting the longest nerves first often causing symptoms in the feet

What is autonomic neuropathy?

Damage to nerves controlling internal organ functions

What is demyelinating polyneuropathy?

A disorder involving damage to the myelin around peripheral nerves

What is Guillain-Barré syndrome associated with?

Demyelinating polyneuropathy

What is the difference between sensory and motor neuropathy?

Sensory neuropathy affects sensory nerves | motor neuropathy affects motor nerves

What is a radiculopathy?

A disorder of spinal nerve roots that can cause radiating pain and abnormal sensations

What is radiculitis?

Inflammation of spinal nerve roots

What is a nerve plexus injury?

Damage to a network of nerves between the spinal roots and peripheral nerves

What is a neuromuscular junction (NMJ) disorder?

A disorder that interferes with communication between motor nerves and muscles

What is myasthenia gravis?

An autoimmune disorder in which antibodies attack postsynaptic acetylcholine receptors

What are common manifestations of myasthenia gravis?

Weakness that worsens with activity and improves with rest | double vision | difficulty chewing | difficulty swallowing

What is Lambert-Eaton myasthenic syndrome (LEMS)?

An autoimmune disorder in which antibodies attack presynaptic calcium channels and reduce acetylcholine release

How does myasthenia gravis differ from LEMS?

Myasthenia gravis affects postsynaptic acetylcholine receptors | LEMS affects presynaptic calcium channels

What is a myasthenic crisis?

Severe muscle weakness that can cause respiratory distress

What is a primary brain tumor?

A tumor that originates in the brain or its surrounding structures

What is a metastatic brain tumor?

A tumor that spreads to the brain from cancer originating elsewhere in the body

Which cancers commonly spread to the brain?

Lung cancer | breast cancer

What are common manifestations of brain metastases?

Headache | seizures | cognitive changes | altered mental status | behavioral changes

What are gliomas?

Tumors arising from glial cells that support nervous system tissue

Which tumors are included among gliomas in the slides?

Astrocytomas | oligodendrogliomas | mixed oligoastrocytomas | glioblastoma multiforme

What is an astrocytoma?

A tumor that develops from astrocytes and can infiltrate surrounding brain tissue

What are early manifestations of astrocytomas?

Headache | subtle neurobehavioral changes | focal or generalized seizures

How does an astrocytoma differ from a glioblastoma?

Astrocytoma is a broad tumor category with different grades | glioblastoma is an aggressive high-grade astrocytic tumor

What is an oligodendroglioma?

A tumor arising from oligodendroglial cells that is often slow-growing and may contain cysts or calcification

What is an ependymoma?

A tumor arising from ependymal cells lining the brain ventricles or spinal canal

What is a meningioma?

A usually slow-growing tumor arising from arachnoid cap cells in the meninges

What is a nerve sheath tumor?

A tumor arising from cells associated with peripheral nerves such as schwannomas or neurofibromas

What is a spinal cord tumor?

A tumor that originates in or around the spinal cord or spreads there from another site

What is an intramedullary spinal cord tumor?

A tumor originating within spinal cord tissue that can invade and compress neural tissue

What is an extramedullary spinal cord tumor?

A tumor originating outside the spinal cord that causes dysfunction mainly by compression

What is an intradural spinal cord tumor?

A tumor located inside the dura but outside the spinal cord tissue

What is an extradural spinal cord tumor?

A tumor located outside the dura often involving epidural tissue or vertebral structures

Which cancers can metastasize to the spinal region?

Breast cancer | lung cancer | prostate cancer | lymphoma | myeloma

What are common symptoms of spinal cord tumors?

Progressive weakness | sensory changes | pain | difficulty walking | possible bladder or bowel dysfunction

What is a compressive syndrome from a spinal cord tumor?

Compression of spinal cord pathways causing sensory and motor dysfunction

What is an irritative or radicular syndrome from a spinal cord tumor?

Irritation of nerve roots causing radiating pain or abnormal sensations