Exam 3 Study Guide Flashcards

300 practice flashcards covering neurology, sensory systems, and musculoskeletal pathophysiology based on lecture notes.

Ischemia

Cell death occurring when oxygenated blood levels are lower than needed to meet the metabolic demands of brain tissue.

Hypoxia

A deficiency of oxygen at the cellular level resulting from lower blood flow or low blood oxygen levels.

Mitochondrial Failure

A consequence of hypoxia leading to the depletion of $ATP$ and accumulation of intracellular calcium ions.

Glutamate

The main CNS neurotransmitter and an excitotoxin that can overstimulate neurons to the point of exhaustion.

Ischemic Cascade

A series of events where increased glutamate leads to calcium overload, cytotoxic edema, and nitric oxide production.

Nitrous Oxide

Produced in excess by neurons due to glutamate overstimulation, leading to free radical formation and cell death.

Reperfusion injury

Damage caused by restoring blood flow, which generates additional free radicals and recruits immune cells to the brain.

Autoregulation (Cerebral)

The mechanism maintaining cerebral blood flow when mean arterial blood pressure is between $60-140\,mmHg$.

Cerebral Vasodilation

The widening of cerebral vessels triggered by hypoxia and high partial pressure of carbon dioxide.

Cerebral Vasoconstriction

The narrowing of cerebral vessels caused by hyperventilation and low carbon dioxide levels.

Intracranial Pressure (Normal)

The pressure within the skull, normally ranging from $0-15\,mmHg$.

Intracranial Pressure (Impairment)

Brain impairment starts to occur when pressure is $>22\,mmHg$ for longer than $5\,minutes$.

Monroe-Kellie Doctrine

The principle that the sum of the volumes of brain tissue, cerebrospinal fluid, and blood is constant.

Intracranial Compliance

The ability of the skull components to compensate for volume increases by decreasing another component to maintain pressure.

Vasogenic Edema

Interstitial edema resulting from vascular incompetency forcing fluid, electrolytes, and proteins into intercellular spaces.

Cytotoxic Edema

Intracellular edema caused by cellular energy failure, $ATP$ deficiency, and $Na^+$ accumulation attracting water into cells.

Level of Consciousness (LOC)

The most sensitive and earliest clinical manifestion of increased intracranial pressure.

Vomiting without nausea

A moderate clinical sign of increased intracranial pressure, referred to as emesis.

Glasgow Coma Scale (GCS)

A tool used to assess neurological status based on eye-opening, verbal, and motor responses.

Cushing Triad

A critical late sign of increased ICP characterized by hypertension (wide pulse pressure), bradycardia, and fluctuating respirations.

Cheyne-Stokes respirations

A late and deadly sign of increased ICP characterized by irregular breathing patterns.

Nuchal Rigidity

A stiff neck where the patient cannot flex their chin toward their chest, often associated with increased ICP or meningitis.

Obstructive Hydrocephalus

Increased cerebrospinal fluid volume caused by a blockage in the fluid pathway.

Pseudotumor Cerebri

A condition causing increased cerebrospinal fluid volume without a specific obstructive cause.

Dural Sinus Thrombosis

A cause of increased blood volume within the skull leading to elevated intracranial pressure.

Acidosis

A condition associated with high arterial partial pressure of carbon dioxide that increases intracranial blood volume.

GCS Eye Opening (Max)

The highest score for eye-opening response, which is $4$.

GCS Verbal Response (Max)

The highest score for verbal response, which is $5$.

GCS Motor Response (Max)

The highest score for motor response, which is $6$.

Cranial Nerve III

The Oculomotor nerve; increased pressure on this nerve due to midbrain displacement causes mild pupil dilation and absent light response.

Fixed and Dilated Pupils

A clinical sign indicating poor brain perfusion.

Pinpoint Pupils

Small pupils typically associated with a pons issue or certain drug effects.

Doll's Eyes Test

An oculovestibular reflex test where a normal result involves the eyes moving opposite the direction of head movement.

Cold Calorics Test

A test where cold water is placed in the ear; eyes deviating toward the side of the cold water indicates a normal response.

Corneal Reflex

A reflex test where touching the cornea with a cotton swab induces a blink; absence indicates brainstem dysfunction.

Focal (coup) injury

A Traumatic Brain Injury localized to the site of impact.

Polar (coup-countercoup) injury

Brain injury occurring at the site of impact and on the opposite side due to forward-backward acceleration/deceleration.

Diffuse axonal injury

Widespread damage from multiple brain movements shifting and rotational forces that shear white matter; often leads to coma.

Primary Injury

The original damage suffered during a traumatic brain event.

Secondary Injury

Complications from the body's response to primary injury, such as cerebral edema, seizures, or vessel spasms.

Epidural Hematoma

A bleed located between the inner skull and the dura mater, typically involving arterial vessels.

Subdural Hematoma

A bleed located between the dura and the outer arachnoid membrane, often caused by tearing of bridging veins.

Bridging Veins

The vessels typically responsible for subdural hematomas when stretched or sheared during falls or car crashes.

Subarachnoid Hemorrhage

A bleed located between the outer arachnoid membrane and the pia mater; blood may be noted in the CSF via spinal tap.

Stroke

A sudden onset of neurological dysfunction attributable to cerebrovascular disease.

Ischemic Stroke (Thrombotic)

A stroke where a clot forms at the site of an atherosclerotic plaque, occluding an existing narrowed vessel.

Ischemic Stroke (Embolic)

A stroke where a clot or plaque travels from heart chambers or other vessels to the brain.

Penumbra

The area around a necrotic core that remains viable due to collateral circulation during an ischemic stroke.

Lacunar Infarcts

Occlusions of small arterioles, often associated with hypertension or diabetes, affecting motor and sensory functions.

Hemiparesis

Loss of motor or sensory function appearing on the opposite side of the brain injury.

Left Hemisphere MALL

Acronym for deficits in Math, Awareness, Logic, and Language.

Right Hemisphere FUSE

Acronym for deficits in Facial recognition, Unawareness, Spatial issues, and Emotional lability.

Hemorrhagic Stroke

Bleeding within the brain, primarily caused by longstanding hypertension and having a higher mortality rate than ischemic stroke.

Cerebral Aneurysm

A congenital weakness in arterial walls leading to ballooning, primarily occurring at the Circle of Willis.

Saccular (Berry) Aneurysm

The most common type of aneurysm caused by a congenital defect in the medial vessel layer.

Sentinel Leaks

Small leaks before a major aneurysm rupture that lead to severe headaches.

Thunderclap Headache

An excruciating, sudden headache characteristic of an aneurysm rupture.

Vasospasm

A complication occurring $4-14\,days$ after subarachnoid rupture due to blood in the CSF, leading to further ischemia.

Hydrocephalus

A potential complication of aneurysm rupture where CSF flow becomes clogged by blood.

Arteriovenous Malformation (AVM)

A congenital malformation where arterial blood is shunted directly into the venous system without a capillary bed.

Vascular Steal Syndrome

A condition in AVM where abnormal shunting causes ischemia in surrounding normal tissues.

Epileptogenic Focus

The area where a seizure starts and from which it can spread outward.

Status Epilepticus

A repeated seizure state without recovery time in between, which can lead to hypoxia and cardiac dysrhythmias.

Focal Aware Seizure

A seizure limited to one body part or sensation with no change in the level of consciousness.

Focal Impaired Awareness

A seizure originating in one area of the brain that involves a loss or alteration of consciousness.

Tonic-Clonic Seizure

A generalized onset seizure involving stiffening followed by jerking, along with cyanosis and a post-ictal period.

Tonic phase

The portion of a seizure characterized by muscle stiffening.

Clonic phase

The portion of a seizure characterized by rhythmic muscle jerking.

Absence Seizures

Seizures, usually in children, characterized by staring spells lasting $2-10\,seconds$.

Parkinson Disease

A degenerative disorder caused by the loss of dopaminergic neurons and associated with Lewy bodies.

Lewy Bodies

Alpha-synuclein protein dumps that disrupt brain function and are found in Parkinson's disease.

Bradykinesia

Decreased speed of movement, facial expression, and eye blinking, characteristic of Parkinson's.

Cogwheel Rigidity

A type of muscle stiffness found in Parkinson's disease where movement occurs in jerky, rhythmic increments.

Pill-rolling

A characteristic unilateral resting tremor of the hand seen in early Parkinson's disease.

Paradoxical Kinesia

The unexpected ability of a Parkinson's patient to move quickly during an emergency.

Bell's Palsy

Idiopathic inflammation of the facial nerve ($Cranial\,nerve\,VII$) leading to unilateral facial paralysis.

Hyperacusis

A decreased tolerance to sound, which can occur as a clinical manifestation of Bell's palsy.

Trigeminal Neuralgia

Chronic compression of the trigeminal nerve ($Cranial\,nerve\,V$) leading to excruciating electric shock-like facial pain.

Migraine Aura

Visual disturbances or flashing lights that may precede the onset of a migraine headache.

Phonophobia

An abnormal sensitivity to sound, commonly reported during migraine episodes.

Perilymph

Fluid in the ear that initiates movement in the endolymph when the oval window moves.

Endolymph

The fluid contained in the vestibular membrane of the ear whose motion stimulates hearing hair cells.

Semicircular Canals

Structures in the ear containing hair cells that control balance and upright posture.

Vertigo

The sensation of motion or aggravation of motion; the cardinal symptom of vestibular system disorders.

Conductive Hearing Loss

Hearing loss caused by disorders of the outer or middle ear that prevent sound from traveling.

Sensorineural Hearing Loss

Hearing loss resulting from dysfunction of hair cells or neural pathways in the inner ear.

Otosclerosis

A condition where healthy bone is replaced by spongy bone in the ossicles (usually the stapes), causing conductive hearing loss.

Presbycusis

Gradual, bilateral sensorineural hearing loss common in older adults, affecting higher pitched sounds.

Meniere Disease

Chronic inner ear disease characterized by the triad of vertigo, tinnitus, and progressive unilateral sensorineural hearing loss.

Otitis Media

Inflammation of the middle ear commonly resulting from eustachian tube dysfunction after a URI.

Cholesteatoma

A collection of skin tissues in the middle ear that can form as a result of chronic otitis media.

Myopia

Nearsightedness; the eye is elongated, and images fall in front of the retina. Corrected with concave lenses.

Hyperopia

Farsightedness; the eye is shorter than normal, and images fall behind the retina. Corrected with convex lenses.

Presbyopia

The loss of lens accommodation with age, leading to a decreased ability to see objects up close.

Astigmatism

A refractive error caused by an irregular curvature of the cornea or lens, producing distorted images.

Strabismus

Ocular misalignment (crossed eyes) due to poor muscle control; can lead to amblyopia if untreated.

Amblyopia

Reduced vision in one or both eyes due to alterations in visual development, such as from strabismus or cataracts.

Cataracts

Clouding of the lens due to oxidative stress, leading to blurred vision and altered color perception.

Retinal Detachment (Exudative)

Accumulation of serous fluid behind the retina due to hypertension or inflammation.

Retinal Detachment (Tractional)

Mechanical detachment where scar tissue pulls the retina away from the back of the eye.