Final studying (everything) Flashcards
Lectures 1-12
List and describe the 3 approaches to anatomy
1) Regional: emphasizes relationships of various systemic structures within the region along with surface anatomy
2) Systemic: study by organ systems
3) Clinical (applied): structure and function of the body important in the practice of medicine; both regional and systemic for clinical application
List the 3 layers of the skin from external to internal
Epidermis, dermis, and subcutaneous tissue (hypodermis or superficial fascia)
1) What type of cells make up the epidermis?
2) How thick is the epidermis?
3) What keeps the epidermis from just falling off the body?
4) List some defining characteristics of the epidermis
5) Is there nervous system involvement in the epidermis?
1) Stratified squamous epithelium
2) 0.5-1.5 mm thick
3) Epidermal ridges “lock” onto papillary dermis
4) Keratinized, shedding, avascular
5) Some afferent sensory receptors: pain, temp, touch
1) How thick is the dermis?
2) What type of tissue makes up the dermis?
3) What type of testing can be done on the dermis?
4) What feature is it responsible for? What is a pathology of this area?
1) Varies in thickness from 0.3 mm (eyelids) to 3.0 mm (back)
2) Connective tissue
3) ID testing; PPD, allergy skin testing
4) Tension lines; stretch marks (collagen + elastic fibers)
1) Give two other names for subcutaneous (SQ) tissue
2) What makes up SQ tissue?
3) What runs through SQ tissue?
4) How is this layer important to medicine?
1) The hypodermis or superficial fascia
2) Loose connective tissue (superficial) and adipose tissue storage
3) Vessels, lymphatics, & cutaneous nerves
4) It’s the layer we infiltrate for local anesthesia for minor procedures; suturing, I&D
1) Where can deep (investing) fascia be found?
2) What are two features of deep fascia? [What do they do?]
3) How is deep fascia medically significant? (2 ways)
1) Envelops most of the body; deep to skin and SQ
2)
a) Retinacula [hold tendons during joint movement]
b) Bursae [are closed sacs with fluid to prevent friction]
3) Responsible for facial planes and compartments within the extremities
1) What two things allow us to feel touch and pressure?
2) What two things allow us to feel pain, itch, and temperature?
1) Meissner’s and Vater-Pacini corpuscles in dermis
2) Papillary dermis/ epidermal ridges
1) What ANS fibers are associated with apocrine sweat glands? What else are they associated with?
2) What ANS fibers are associated with eccrine sweat glands? What is unique about them?
1) Adrenergic fibers; vasculature and erector pili
2) Cholinergic fibers (unique neurotransmitter for sympathetic)
List and describe the 3 types of burns
1) Superficial: superficial epidermis involved. Ex: sunburn
2) Partial thickness:
Into superficial dermis, sweat glands and hair follicles may provide regenerative cells
3) Full thickness: Entire epidermis and dermis, even SQ and muscle may be involved; requires skin grafting
1) All bone is derived from what?
2) What are the two types of bone formation?
1) Mesenchyme
2) Intramembranous and endochondral ossification
1) When does intramembranous ossification happen and how?
2) What type of arteries supply bone marrow, spongy bone, deeper compact bone?
3) What type of arteries supply most of the compact bone?
1) During fetal period; bone forms directly from mesenchyme
2) Nutrient arteries
3) Periosteal arteries (periosteum = vital like bark on a tree)
1) List the 3 types of joints
2) What type of joint is associated with DJD, RA, and gout?
1) Fibrous, cartilaginous, and synovial
2) Synovial
1) What describes how nerves supplying the joint also supply the muscles moving the joint and the overlying skin?
2) Why can synovial joints be painful?
3) What sense are joints responsible for?
1) Hilton Law
2) Pain fibers in fibrous layer joint capsule
3) Proprioception
1) Define motor unit
2) The heart and blood vessels make up the ________ system
1) A LMN and the muscle fibers it innervates
2) Cardiovascular
List the 3 layers of blood vessels and what each is made of
1) Tunica intima: endothelial lining
2) Tunica media: smooth muscle
3) Tunica adventitia: outer connective tissue
List 4 functions of the lymphatic system
1) Interstitial fluid balance
2) Filter system
3) Digestive function (chyle)
4) Immune function
What are the two main ducts of the lymphatic system? What parts of the body do they serve?
1) Right lymphatic duct drains upper right quadrant of body
2) Thoracic duct drains the rest
What type of structure secretes hormones?
Glands
What illnesses does “chronic lung diseases” include?
COPD, asthma, RSV in infants, HMD, lung cancer, interstitial lung disease
CF, bronchiectasis
Name 4 functions of the digestive system
1) Breaks down food into absorbable units
2) Immune function
3) Hormonal function
4) Exocrine function
List 4 functions of the urinary system
1) Water/electrolyte balance
2) Waste removal
3) Acid base balance
4) Hormonal functions
(EPO and RBCs, renin and blood pressure)
1) Name 3 chronic kidney diseases
2) List 2 other illnesses of the urinary system
1) T2DM, HTN, Autoimmune disease (Lupus)
2) UTI (cystitis/pyelonephritis) and post-strep glomerulonephritis
Name 4 functions of the skeletal system
1) Protects and supports body organs
2) Framework for muscles
3) Mineral storage
4) Blood cell formation
What are the two divisions of the skeletal system?
Axial (main portion) and appendicular (pelvic girdle, clavicle, scapula, and limbs)
List 5 functions of bone
1) Protection for vital structures
2) Support for the body and vital cavities
3) Mechanical basis of movement
4) Storage of minerals
5) Manufacture blood in medullary cavities
What’s the difference between radiolucent and radiodense?
1) Radiolucent tissues absorb minimal x-rays = blacker appearance on the “film”
2) Radiodense tissues absorb more x-rays = whiter appearance on the “film”
What two types of imaging have transverse sections as their anatomic view?
CT scans and MRIs
What two types of imaging don’t use radiation?
MRI and ultrasonography
What property does a CT image depend on?
Density
1) What units is density expressed in (in regards to CT scans)?
2) What terms are used to compare structures?
1)Hounsfield unit (HUs), whichspans from +1000 for bones (bright), 0 for water (gray), to -1000 for air (dark)
2) Hyperdense,hypodenseorisodense
1) What do PET scans evaluate? Why?
2) What 2 things can it detect?
1) Physiological function (since they’re dynamic)
2) Increased function and cancer
1) What is Doppler ultrasonography?
2) Give 2 examples of this type of ultrasonography
1) Ultrasounds adjusted for examining blood flow through arteries and veins
2) Transcranial ultrasonography and carotid ultrasonography
Give an example of something that crosses tension lines
Stretch marks
1) What is another name for the cuticle of a nail?
2) What is immediately proximal to this (but underneath the skin)? What’s behind that?
1) Eponychium
2) Root of nail, behind it is the nail matrix
What are the 3 parts of a tooth from superior to inferior?
1) Crown
2) Neck
3) Root
1) What is the most external layer of teeth called?
2) What layer is directly below that?
3) What are those layers protecting?
1) Enamel
2) Dentin
3) The pulp cavity and root canal
What is the primary function of the sympathetic nervous system?
Controlling blood vessels
1) What is plaque?
2) What is a thrombus?
1) A buildup of fat (mostly cholesterol) in arteries
2) A blood clot in arteries as a result of platelets, proteins, and RBCs sticking together
What structure is the body’s internal thermostat? (not in the brain)
The thyroid
1) What is the endocrine function of the testes?
2) What is their exocrine function?
1) Endocrine: secrete testosterone
2) Exocrine: sperm
1) What part of breathing is passive? What part is active?
2) Give an example of a condition that might cause this to change
1) Exhaling is passive, inhaling is active
2) Asthma may cause forceful exhaling
Is the urinary system involved in endocrine functions, exocrine functions, or both?
Both
When does a UTI become cystitis/ pyelonephritis?
When it reaches the kidneys
What are the 5 basic radiodensities?
1) Air: Also known as radiolucent, air appears black on a radiograph.
2) Fat: Appears as a darker gray on a radiograph.
3) Water or soft tissue: Appears gray on a radiograph.
4) Bone: Appears less white than metal on a radiograph.
5) Metal: Also known as radiopaque, metal appears white on a radiograph
What are the 5 elements of neurons?
1) Cell body
2) Dendrites
3) Axons
4) Myelin sheath around some axons
5) Synapse
What is the mnemonic to help remember the order of the cranial nerves?
Oh Once One Takes The Anatomy Final Very Good Vacations Are Heavenly
1) What type of neuron cell bodies tend to be in the CNS?
2) What about the PNS?
1) Motor tend to be in CNS (UMN, LMN)
2) Sensory tend to be in PNS (DRG)
1) What do dendrites do?
2) What do axons do?
1) Dendrites: impulses from receptors to neuron
2) Axons: impulses from neuron to site of action
What do synapses do?
Communicate with neurotransmitters (excite or inhibit)
What are the 3 functions of myelin?
1) It acts as an electrical insulator for the neuron
2) Prevents depolarization
3) It speeds up conduction/ transmission of an electrical impulse
Define nucleus and give an example
Collection of nerve cell bodies within CNS (lateral geniculate nucleus in thalamus)
1) Define gray matter
2) Where’s it’s located?
3) What are the parts of this location?
1) Nerve cell bodies
2) The brain and grey matter horn (H) in spinal cord
3) Parts of horn: anterior (motor), dorsal (sensory), lateral (sympathetic and parasympathetic)
1) What is white matter?
2) What are the 3 layers of meninges?
3) Where is the CSF?
1) Fiber tracts
2) Pia, arachnoid, dura mater (split in cranium)
3) Subarachnoid space
1) A collection of nerve cell bodies within CNS is called?
2) A collection of nerve cell bodies outside of the CNS is called?
3) A bundle of nerve fibers (axons) connecting nuclei in CNS is called?
1) Nerves
2) Ganglia
3) A tract
List the order of the spinal nerve sections and how many nerve are in each section
Cervical-8
T-12
L-5
S-5
Coccygeal-1
What are the functional components of the nervous system? Define each.
What may both have?
1) Sensory (afferent): toward brain
2) Motor (efferent): away from brain
3) Somatic (voluntary) and visceral (involuntary) components
What are the two structural categories of the nervous system? Define each
1) CNS: brain and spinal cord
2) PNS: cranial and peripheral nerves “outside” the CNS
1) Define the somatic nervous system
2) What does it provide, and what to? What are the exceptions?
3) What 4 things does it transmit?
4) What does it stimulate?
1) Somatic parts of CNS and PNS
2) General sensory and motor to all parts of body (soma)
-Except: viscera in body cavities, smooth muscle, and glands
3) Touch, pain, temperature, proprioception
4) Skeletal (voluntary) muscle contraction
1) Define visceral nervous system
2) What does it provide? To where?
3) What are its 3 functions?
4) What 3 things does it stimulate?
1) Visceral (autonomic) parts of CNS and PNS
2) Visceral sensory and motor innervation to viscera, smooth muscle, and glands
3) Visceral sensory pain, reflexes, regulates visceral function
4) Smooth muscle in walls of vessels and organs, modified cardiac muscle (intrinsic stimulating and conducting tissue), and glands
What is the mnemonic to help remember whether a cranial nerve is sensory, motor, or both?
Some Say Money Matters But My Brother Says Big Brains Matter More
1) What CN nerve(s) arise from the brain?
2) Which CN nerve(s) arise from the spinal cord? What part of the spinal cord and where does it/they go?
1) CN I-X and XII arise from brain
2) CN XI (spinal accessory n.) from cervical spinal cord to transverse foramen magnum into skull
1) What are the 2 types of cranial motor nerves?
2) What are the 3 types of cranial sensory nerves?
1) Somatic and visceral (aka autonomic)
2) Somatic, visceral, special (vision, hearing, taste, balance)
1) The specific region innervated by each somatic spinal nerve is called what?
2) Where are dermatomes guaranteed to end?
3) Why is this important?
1) A dermatome
2) The midline
3) Meningitis sometimes will remain on one side because of dermatomes
1) Are spinal nerve roots sensory, motor, or both?
2) What does is the posterior ramus innervate?
1) Both sensory and motor
2) Mid back
What 3 things are found within the anterior ramus of a spinal nerve?
1) White ramus communicans
2) Sympathetic truck (also runs through posterior)
3) Gray ramus communicans
1) Where does the anterior ramus go?
2) True or false: Peripheral nerves are mixture of modalities
1) Continues to remainder of soma (body)
2) True
What are the 3 types of fibers found within peripheral nerves?
Afferent, efferent, and postsynaptic sympathetic fibers
1) If you feel touch just above your mid back, what ramus is this going to?
2) If you feel touch in your arm, what ramus is this going to?
1) Posterior ramus of spinal nerve
2) Anterior ramus of spinal nerve
1) What type of ganglia are closer to their target organ?
2) What kind is further?
1) Parasympathetic
2) Sympathetic
What is the difference in origin between an upper motor neuron (UMN) and a lower motor neuron (LMN)?
1) UMNs: originate in the cerebral cortex, travel down to the spinal cord or brainstem
2) LMNs: begin in the spinal cord.
Sympathetic (thoracolumbar) division of motor innervation:
1) Where does it come from and go?
2) What is its primary function?
3) Is it catabolic or anabolic? Why?
1) Outflow from CNS to T1-L3
2) Regulate BP (also has other functions)
3) Generally catabolic; to prepare for flight or fight
What are the two divisions of visceral (autonomic) motor innervation?
Sympathetic (thoracolumbar) and parasympathetic (craniosacral)
Parasympathetic motor innervation:
1) Where does it come from and go?
2) Is it catabolic or anabolic? Why?
1) Outflow from the CNS to CNs 3,7,9,10 and S2-3-4
2) Generally anabolic, because it’s promoting normal function and conserving energy
1) Where are the visceral presynaptic (preganglionic) neurons located? Where do they terminate?
2) Where are the visceral postsynaptic (postganglionic) neurons located? Where do they terminate?
-Give examples
1) Grey matter (nuclei) in CNS; synapse with 2nd neuron
2) Outside of CNS in ganglia (paravertebral ganglia); terminate at effector organs
-Exs: smooth muscle, glands, cardiac conduction tissue, etc
Sympathetic motor division:
1) Where are its presynaptic neurons? Where do their fibers outflow?
2) Where are its postsynaptic neurons? What are they conveyed by?
1) Lateral Horn of spinal cord; via thoracolumbar nerves (T1-L3)
2) In paravertebral and prevertebral ganglia; by all branches of the spinal nerves
1) What is the primary function of the sympathetic motor division?
2) What does symp. motor innervate?
3) Are parasympathetic motor fibers related to spinal nerves? If so, how?
1) Modulate BP
2) Smooth muscles of blood vessels, sweat glands, erector pili m. of the skin, cardiac conduction tissue
3) Have limited association with spinal nerves (S 2-3-4)
1) Define paravertebral ganglia
2) What is located here?
3) What is the most superior paravertebral ganglia? Where is it?
4) What is the most inferior? Where is it?
1) Symp.trunks/ chains on either side of vertebral column
2) Symp. postsynaptic neurons
3) Superior cervical ganglia; base of cranium
4) Ganglion impar; where two chains unite at level of coccyx
1) Where are the sympathetic presynaptic neurons found?
2) What part of the spine is this?
1) Paired left and right IMLs (aka lateral horns/ grey matter of cord)
2) T1-L2/L3
What are the two locations of sympathetic postsynaptic neurons? (hint: both ganglia)
1) Paravertebral ganglia
2) Prevertebral (preaortic) ganglia
1) Where are prevertebral (preaortic) ganglia found? (4 places)
2) What is found within them?
1) In plexuses that surround origins of the main branches of the abdominal aorta (celiac ganglia) and the aortic, hypogastric, and pelvic plexuses that descend from them
2) Sympathetic postsynaptic neurons
1) Where do symp. presynaptic motor fibers that provide autonomic innervation within the head, neck, body wall, limbs, and thoracic cavity go?
2) Where do they exit and go?
3) Where do symp. presynaptic fibers innervating viscera within the abdominopelvic cavity pass through? Where do they synapse?
1) Either ascend within the paravertebral ganglia at current level, ascend or descend then synapse
2) Via grey communicans; into the spinal nerves.
3) Sympathetic chain; within the prevertebral (preaortic) ganglia (then to their effector organ)
Describe the path of the symp. postsynaptic motor fibers that innervate below the head (3 steps)
1) Paravertebral ganglia of sympathetic trunk, then through Gray rami communicantes
2) To adj. anterior rami of spinal nerves
3) Then enter all 31 spinal nerves (incl. posterior rami)
What fiber innervation controls sweating, goosebumps, and vasomotor tone/ BP?
Postsynaptic somatic motor
What is the path of sympathetic motor fibers that go to the head? (3 steps)
1) Post synaptic cell bodies in superior cervical ganglion
2) Follow periarterial plexus of nerves (near br. of carotid artery) into cranium.
3) Hitch a ride with CNs to target organ
1) What do splanchnic postsynaptic symp. motor fibers go through to the viscera of thoracic cavity?
2) Where do they terminate? (3 places)
3) What do they form?
1) Cardiopulmonary splanchnic nerves
2) Cardiac, pulmonary and esophageal plexuses
3) Peri-arterial plexuses
-(following arterial branches to target organs)
What type of nerves do splanchnic presynaptic symp. motor fibers use to innervate the viscera of abdominopelvic cavities?
Abdominopelvic splanchnic nerves
What type of fibers are the suprarenal gland innervated by? Where do these terminate?
Presynaptic sympathetic fibers; directly onto adrenal medulla cells
What do adrenal medulla cells act as?
Postsynaptic neurons
1) What are the two types of parasympathetic outflow?
2) What are the two places one of these types goes to?
1) Cranial and sacral
2) Cranial: head and thoracic/abd. viscera
1) List the 3 CNs parasympathetic cranial outflow use to innervate the head
2) List the 4 ganglia parasympathetic cranial outflow uses to innervate the head
1) #s 3, 7, 9
2) Ciliary (pupil), terygopalatine (lacrimal gland), otic (parotid gland), submandibular (sublingual and submandibular salivary glands)
What type of innervation does CNX use to innervate the thoracic and abd viscera above the splenic flexure?
Parasympathetic cranial
1) Where does parasympathetic sacral outflow (innervates body) come from?
2) Describe the path they take.
3) How many places are innervated by this type of outflow? List them
1) S 2-3-4
2) Lateral horn grey matter via anterior S2-4 spinal nerve, anterior rami to pelvic splanchnic nerves
3)
A) Pelvic viscera
B) Erectile tissues of external genitalia and bladder
C) GI from pelvic flexure of colon distal (descending colon, sigmoid colon, & rectum)
1) Does the enteric nervous system rely on the CNS?
2) What modulates the enteric nervous system, just parasympathetic, symp, or both?
1) Functions autonomously from CNS
2) Parasympathetic and sympathetic input
What makes up the enteric nervous system?
Two interconnected plexuses: myenteric (in smooth musc. wall) and submucosal (deep to mucosa)
What 4 things does the enteric nervous system do?
Controls local input and reflex activity for:
1) Exocrine & endocrine secretion
2) Vasomotion
3) Micro-motility
4) Immune activity of the gut
What type of innervation gives input to CNS regarding condition of internal environment and controls visc. and somatic reflexes? Is it usually percieved?
Visceral afferent; no, but can be pain/ hunger/ nausea
Referred pain and nausea caused by a heart attack involves what part of the nervous system?
Visceral afferent
Define myotome
A group of muscles innervated by a single spinal nerve root
What does the corticospinal tract run through in the spine?
The lateral column
1) Where does the vertebral column start and end?
2) How many vertebrae are there in each section of the spine?
1) Goes from cranium to the apex of the coccyx
2) C7, T12, L5, S5, Co4
Name 6 things the vertebral column does
1) Main support of the axial skeleton
2) Protects the spinal cord and nerves
3) Supports weight of body superior to sacrum
4) Rigid-flexible axis for body
5) Pivots the head
6) Posture for body
1) What is a major stress point of the vertebral column?
2) What part(s) of the vertebral column allow for significant amount of motion?
1) Lumbosacral angle (L5-S1 junct.)
2) Superior 25 vertebrae, most in cervical
What two sections of the spinal column is most motion in?
Cervical and lumbar
What 3 things provide stability to the vertebral column?
1) Shape and strength of vertebrae and IV disc
3) Ligaments
4) Muscles
List the 4 curves of the adult spine from top to bottom. Specify whether each is primary or secondary
1) Cervical lordosis, secondary
2) Thoracic kyphosis, primary
3) Lumbar lordosis, secondary
4) Sacral kyphosis, primary
1) What is a developmental condition that can cause abnormal spinal curvature (that can be both lateral and rotational)?
2) What is a pathologic condition that can cause abnormal spinal curvature?
1) Scoliosis
2) Osteoporosis
An anterior rotation of pelvis, causing an abnormal increase in the lumbar lordosis curve, is defined as what?
Lordosis
What are the 3 components of a typical vertebrae?
1) Body
2) Arch (contains pedicle & lamina)
3) 7 processes
1) What are the endplates of a vertebral body covered in?
2) What is the epiphyseal rim made of?
3) Where on the column do vertebral bodies increase in size?
1) Hyaline cartilage
2) Bone
3) T4-S1
What are the 2 features of a typical vertebral arch? List and describe them
1) Paired pedicles: Connect arch to body; form vertebral notches and adjacent vertebral notches for intervertebral foramen
2) Paired lamina: Unite at midline
1) Define vertebral foramen
2) What do vertebral notches form
3) What is typically between vertebral bodies?
1) Spinal canal where spinal cord resides
2) Intervertebral (IV) foramina
3) IV disc
List the 7 processes of a typical vertebrae
1) Spinus process (dorsal)
2&3) Paired transverse processes
4,5,6,7) Paired superior and inferior articular processes
What do the paired superior and inferior articular processes of the vertebrae form?
Zygapophyseal (facet) joints
What are the two foramen found in cervical vertebrae, and what runs through them?
1) Large triangular vertebral foramen: spinal cord and cervical nerve roots
2) Foramen transversarium (absent C7): vertebral artery & vein, and sympathetic nerves
What is unique about C7?
It doesn’t have a foramen transversarium (unlike the other cervical vertebrae)
Do cervical and thoracic spinal nerves exit via the intervertebral (IV) foramen above or below their same numbered vertebra?
1) Cervical: exit IV foramen above the same numbered vertebra
2) Thoracic: exit IV foramen below their corresponding vertebra
1) What is the atlas?
2) What shape is it?
3) What does its transverse ligament do?
4) What does it allow for?
1) The first cervical vertebrae (C1)
2) Ring shaped
3) Separates vertebral foramen from foramen for dens (C2)
4) Allows flex/ext. of cranium (nodding yes)
1) What is the axis?
2) What is unique about the axis?
3) What does its dens (odontoid) articulate with?
4) What does this allow for?
1) C2
3) Strongest
3) Anterior arch of atlas and transverse ligament
4) Rotation of head and atlas about the axis, as in “NO”
Does the axis itself rotate?
No
What vertebrae is most likely to fracture if you dive into shallow water and hit your head?
The atlas (C1) (Jefferson’s fracture)
1) Describe the size of the vertebral bodies and vertebral foramens of the lumbar vertebrae
2) Where does the spinal cord end in adults?
3) Describe the length of the cauda equina
1) Bodies are massive, vertebral foramens are large
2) L1-2 in adults
3) Extends full length of vertebral canal
1) What exits each intervertebral (IV) foramen of the lumbar vertebrae?
2) What is the preferred site to access epidural space for anesthesia & SA space for CSF collection?
3) A defect in pars interarticularis of neural arch (lamina between the two articular processes) can cause what lumbar condition?
1) Spinal nerves
2) Below L2 (since spinal cord ends there), between L3-L4 or L4-L5
3) Spondylolysis
If a patient comes in complaining of radiating leg pain progressing from their upper to lower legs when walking that’s relieved by bending over (like leaning on a shopping cart), what condition might they have?
Lumber stenosis
1) What do spina bifida, meningoceles, and meningomyeloceles have in common?
2) What joints transmit body weight to pelvic girdle?
1) All result from incomplete closure of the neural tube
2) SI joints
What is the sacral promontory?
The anterior edge of the S1 body
1) Describe the texture and shape of the dorsal side of the sacrum
2) What is found on its surface?
3) What are the 3 sacral crests?
4) What is the sacral hiatus? What does it lead to?
1) Rough and convex
2) 4 pair of foramina
3) Median, intermediate, lateral
4) Inferior end of vertebral canal that leads into sacral canal
1) What is the coccyx a remnant of?
2) Are its vertebrae fused?
3) What is its clinical significance?
1) Vestigial tail
2) Distal 3 vertebrae fuse in mid life
3) Can palpate it rectally
1) What is the Conus medullaris?
2) Where does it terminate in newborns?
3) What about in adults?
1) The terminal, inferior end of the spinal cord
2) Newborn: opposite L2/3 IV disc
3) Adult: opposite L1/2 IV disc
What are the 2 potential causes of cauda equina syndrome?
Disc herniation or spinal stenosis
-(Can be caused by cancer, trauma, epidural abscess or hematoma)
If a patient with an epidural abscess suddenly complains of loss of bowel or bladder control, what might be the cause? What might be the cause of that?
Cauda equina syndrome secondary to disc herniation or spinal stenosis (caused by their epidural absess)
If a patient with a history of lower spinal trauma (below L1/2) suddenly complains of numbness around the anus and radiating pain down their leg, what might be the cause? What might be the cause of that?
Cauda equina syndrome secondary to disc herniation or spinal stenosis (caused by their previous spinal trauma)
1) What do superficial [extrinsic] back muscles act on?
2) What innervates them?
1) UE
2) Anterior rami or CN XI
1) Trapezius, lat. dorsi, levator scapulae, rhomboid, and serratus posterior are all examples of what type of back muscle?
2) The 3 serratus muscles and the proprioceptive respiratory muscles are examples of what type of back muscle?
1) Superficial extrinsic
2) Intermediate extrinsic
1) The splenius group that does lateral flexion and rotation and extension of the head/ neck are what layer of back muscles?
2) What layer of muscles are the erector spinae (main extensors of spine) a part of?
3) What layer are the transversospinalis group a part of?
1) Intrinsic superficial
2) Intrinsic intermediate
3) Intrinsic deep
1) What two things are IV discs associated with?
2) What is the more exterior part of the IV discs called? Where does it attach?
3) What is the more interior part of the IV discs called? Where is it located?
1) ROM and natural curvatures of spine
2) Annulus fibrosus (85% water); attaches to end plates
3) Nucleus pulposis; positioned more posteriorly
Describe the shape of annulus fibrosus
Thinner posteriorly (why herniated discs can happen)
List the 5 types of joints found in the vertebral column
1) Vertebral bodies: IV Discs, uncovertebral joints
2) Vertebral arches: Zygapophysial (facet) joints
3) Craniovertebral: occipital condyle with atlas
4) Costovertebral: ribs
5) Sacroiliac: SI joint
1) Describe the joints of the vertebral arches; what type of joints are they?
2) What do they allow for?
3) What are they innervated by?
1) Zygapophysial (facet) joints; synovial
2) Gliding movement
3) Medial branch of posterior rami spinal nerves
What are the 3 branches of the median branch of the posterior rami of spinal nerves?
Muscular, cutaneous and articular branches
1) What are the 4 movements of the spine?
2) What reduces these movements in some people?
3) Why?
4) What innately limits movement?
1) Flexion, extension, lateral flex, rotation
2) Age
3) Primarily from IV-disc compression and elasticity
4) Physical characteristics of the anatomy
Is age the primary cause of reduced spinal movement? Explain
No, it’s secondary to degenerative changes in IV disc and other structures
What 3 things allow movement of the spine?
1) Back and abdominal muscles (like rectus abdominus and obliques)
2) Gravity
3) Movement between adjacent vertebra (Zygapophyseal joints and IV-disc)
What are the two types things that allow movement between adjacent vertebrae?
Zygapophyseal joints and IV-disc
What part of the spine has the greatest degree of flexion ROM?
Cervical spine
What two things limit ROM of the thoracic spine?
Ribs and sternum
1) What allows for greater flexion and extension of the lumbar spine?
2) Is there a lot of rotation of the lumbar spine? Why?
3) Describe the IV discs of the lumbar spine
1) Facet joints
2) Minimal rotation due to interlocking facets
3) Relatively large IV discs
Is extension or flexion greater in the lumbar area?
1) Extension > flexion
(spondylosis in gymnast)
What are the 3 longitudinal arteries that supply the vertebral column?
1) Anterior spinal artery
2&3) Paired posterior spinal arteries
Describe venous drainage of the vertebral column
-Forms venous plexuses:
1) External plexus
2) Internal plexus
Describe the manner in which the venous plexuses that drain the spine communicate
Communicate freely
1) Where is the internal vertebral venous plexus?
2) Where does it drain?
3) What does it communicate with?
1) In epidural space
2) Drains superiorly into dural venous sinus in cranium
3) With external vertebral plexus on external surface of vertebra
What innervates the vertebral column?
Meningeal branches of spinal nerves
1) Where is most body weight in relation to the vertebral column?
2) Where is most muscle support in relation to the vertebral column?
3) What are the two types of back muscles?
1) Anterior
2) Posterior
3) Intrinsic and extrinsic
What are the two types of extrinsic back muscles? What does each do?
1) Superficial: control limb movement
2) Intermediate: control respiratory movement
What are the 3 kinds of intrinsic back muscles? (bonus: give examples of each)
1) Superficial: splenius
2) Intermediate: erector spinae
3) Deep: transversospinalis
1) How are the extrinsic back muscles innervated and what do they do?
2) What is the exception?
1) By anterior rami of c-spinal nerves, act on UE (except for trapezius).
2) Trapezius m. innervated by spinal accessory n., CN XI
1) What are the muscles of the back proper?
2) What innervates them?
3) What do they do?
4) Where are they?
5) What are their groups?
1) The intrinsic muscles of the back
2) Posterior rami branches of spinal nerves
3) Maintain posture and control ROM of the vertebral column
4) Below investing fascial (“invested” in deep fascia) midline to transverse processes and angle of the ribs
5) Superficial, intermediate, and deep layers
1) Give the brief explanation of what intrinsic muscles are innervated by and what they do
2) What are the enclosed in?
1) Innervated by posterior rami of spinal n.; control posture and movement of the spine
2) In deep fascia (thoracolumbar fascia)
1) Where are the suboccipital region and suboccipital triangle?
2) What is it made of?
1) Deep to trapezius and semispinalis capitis mm.
2) 4 small muscles
1) What kinds of muscles form suboccipital region/ what do they act on?
-bonus: what are they?
2) What CN innervates these triangle region muscles? Does this CN provide skin sensory?
1) Mainly postural muscles, act on head (capitis): ext of head and rotate head b/t C1-2
-2 rectus capitis and 2 obliquus capitis
2) Posterior ramus of C1; suboccipital nerve; no skin sensory
What is the clinical correlation of the greater and lesser occipital nerves?
-Can cause occipital neuralgia, which is defined as chronic headaches by the occipital nerves
-Sometimes a nerve block is placed in the greater occipital nerve at the back of the neck
1) What space is spinal anesthesia placed for surgical procedures?
2) What space are CSF samples collected from? What are they also called, and where on the spine do they go?
3) What space is epidural anesthesia placed?
1) Spinal anesthesia: subarachnoid space
2) Subarachnoid space; aka lumbar taps. Done on lumbar cistern below L1-2 where spinal cord ends.
3) Epidural space
What is the pathway of epidurals and LPs (lumbar punctures)?
1) Skin
2) Spinous ligament
3) Ligamentum flavum
4) Epidural space: epidurals stop here
5) Dura-arachnoid meninges
6) Subarachnoid space: lumbar punctures stop here
Bonus: Describe the origins and courses of the greater and lesser occipital nerves
1) Greater occipital nerve: comes from the dorsal rami of C2, goes up the back of head, emerges inferior to obliquus capitis inferior and ascending to posterior scalp
2) Lesser occipital: come from anterior rami of C2-3, goes directly to skin
What makes up the scalp proper? List each part
The first 3 layers:
1) Skin
2) Subcutaneous Connective tissue
3) Epicranial Aponeurosis
What are the layers of the scalp (NOT scalp proper)
1) Skin
2) Subcutaneous Connective tissue (SQ)
3) Epicranial Aponeurosis
4) Loose connective tissue
5) Pericranium
1) Describe skin of the scalp
2) Describe Subcutaneous Connective tissue of the scalp and its clinical correlation
1) Skin: typical with pilosebaceous units and sweat glands, abundant vascular supply
2) SQ: Thick, dense, richly vascularized with cutaneous nerves
-Embedded in dense connective tissue (limited ability to constrict when injured; bleeds a lot)
What is the Epicranial Aponeurosis?
A tendonous sheet of fibrous tissue that covers the calvarium
-Connects the 2 bellies of the occipitofrontalis m. & superior auricular m.
-Continuous with the temporal fascia
Describe the jobs of the occipitalis and frontalis
1) Occipitalis muscles: pull scalp posterior
2) Frontalis muscles: wrinkles forehead, raises eyebrows, pulls scalp forward
Why can a black eye result from injury to scalp of the forehead?
Frontal belly of the occipitofrontalis m. inserts into the skin and SQ tissue, not to the bone
-Loose connective tissue of scalp is a sponge-like layer w potential spaces that may distend w fluid/blood from injury or infection
1) What stops blood and pus from passing from the forehead to the neck?
2) What stops blood and pus from spreading laterally beyond the zygomatic arches?
2) Explain why loose connective tissue of the scalp is such a dangerous area
1) Occipital belly of occipitofrontalis m. attaches to the occipital bone and mastoid parts to mastoid bone.
2) Epicranial aponeurosis is continuous with the temporal fascia that attaches to the arches.
3) Infection can pass into cranium via emissary veins
1) What is the BREGMA?
2) What is lambda?
3) Where are sinuses in relation to the orbits? Why is this clinically relevant?
1) The intersection of the coronal and sagittal suture lines (soft spot in baby)
2) The intersection of the sagittal and lambdoid suture lines
3) Medial and inferior to orbits; extension of infections can lead to orbital abscess
1) Fractures of floor of middle cranial fossa may result in leakage to where? What does this result in?
2) Fractures of floor of anterior cranial fossa may involve what? What does this result in?
What can both increase risk of?
1) External acoustic meatus, CSF otorrhea
2) Cribriform plate of the ethmoid, CSF rhinorrhea
-Meningitis
1) Describe the pericranium
2) What does it form?
1) Dense layer of connective tissue
2) External layer of the periosteum of skull
What can scalp stand for?
1) Skin
2) subcutanous Connective tissue
3) epicranial Aponeurosis
4) Pericranium
What are the two structural and functional parts of the cranium? Briefly describe each
1) Neurocranium: cranial vault or “brain bucket” (made up by calvaria + cranial base)
2) Viscerocranium: facial skeleton
What are the two parts of the neurocranium?
1) Calvaria (skullcap)
2) Cranial base
1) What 5 things does the neurocranium contain?
2) What are its two parts?
3) What bones make it up?
1) Brain, meninges, CSF, proximal CN, vessels
2) Calvaria and cranial base
3) Formed by 8 bones
-4 unpaired: frontal, ethmoid, sphenoid, occipital
-2 paired: temporal and parietal (bilateral)
1) What two things are behind the pterion?
2) What is its clinical significance?
1) Temporal lobe and MMA
2) Can fracture with trauma (and mess with the MMA)
What makes up the facial aspect of the cranium (viscerocranium)? List all parts
15 bones:
-Three unpaired midline bones: mandible, ethmoid, vomer
-Six paired or bilateral bones: maxilla, inferior nasal concha (turbinate) zygomatic, palatine, nasal, lacrimal.
What are the two primary sources of blood to the brain? List the basic path of each
1) Anterior circulation: Internal carotids > middle and anterior cerebral aa. of circle of Willis.
2) Posterior circulation: Vertebral arteries > basilar artery > circle of Willis
What supplies blood to the meninges? (bonus: Describe the basic path)
External carotids
(via maxillary artery through foramen spinosum to middle meningeal artery)
What are the two sources of blood supply to the face and viscera of the head? Describe where each goes
1) External carotid: to major branches to face and viscera
2) Internal carotid: to supra orbital/trochlear vessels for frontal region of scalp (mostly brain tho)
What is the clinical correlation of the meningeal arteries?
-The middle meningeal artery (off the maxillary artery) is in groove of the pterion (the meeting of 3 skull bones)
-Trauma to area/fracture can cause epidural bleed
What artery is at risk if the infratemporal fossa is injured? What CN? What veins?
MMA; CNV2; pterygoid venous plexus
Describe the general vascular supply of the tongue
External carotid and lingual arteries, lingual veins drain into IJV
What are the 3 salivary glands?
Parotids, submandibular, sublingual
1) Where is the submandibular duct?
2) Where do the sublingual glands’ ducts open? What innervates them?
1) Opens onto sublingual papilla opposite of 2nd molar
2) On floor of the mouth; CN8 parasymp. (same as submandib.)
What are the 2 nerves of the face? Describe them
1) CN VII: facial nerve, mostly motor (for facial expression)
2) CN V: trigeminal nerve, mostly sensory, has three named branches called V1-2-3
1) What 2 areas does CNVII innervate?
2) What does it travel? Why is this unique?
3) Where does it exit the face?
4) Where is it located?
1) Internal acoustic meatus and muscles of facial expression
2) Goes through facial canal, which is the longest boney canal any nerve must traverse, so it’s at risk
3) Styloid mastoid foramen
4) Deep to parotid gland
1) What nerve innervates the top half of the head?
2) What does it transmit?
1) CNV (has 3 branches, V1-3. )
2) Just somatic sensory
What does CNI do?
Doesn’t really do much to skin, just to muscles in suboccipital triangle
List what’s embedded in the parotid gland from superficial to deep
1) Parotid plexus of facial nerve
2) CN VII
3) Retromandibular vein
4) External carotid artery + lymph nodes
What are the 3 parts of CNV?
1) V1 - ophthalmic (cornea, nose, forehead)
2) V2 - maxillary (cheeks, tiny piece of nose and top of teeth)
3) V3 - mandibular (mandible, some temporal)
What are the afferent and efferent components of the corneal touch reflex?
Afferent component is V1, motor component is CVII
What are the afferent and efferent components of the light reflex?
Optic nerve is afferent, constriction would be CNIII’s sympathetic division
Where does each part of the trigeminal nerve exit?
V1: supraorbital foramen or notch
V2: infraorbital foramen
V3: mental foramen via mandibular canal
When contracted unilaterally, the lateral and medial pterygoid muscles do what?
Cause a lateral chewing motion, grinding motion
1) What are most arteries to the face branches of?
2) What are most external facial veins drained by?
3) Does this vary? If so, what are the alternate routes?
1) External carotid a.
2) Veins that accompany the arteries
3) Varies; alternate route include superficial and deep drainage
1) Where does the facial artery arise from?
2) What does it supply?
3) Can you palpate its pulse?
1) External carotid a.
2) It’s the major artery to superficial face
3) Yes
1) What does the superficial temporal artery arise from?
2) What is one of its characteristics?
1) External carotid a.
2) Can palpate its pulse
1) What is an inflamed temporal artery called? (2 names)
2) What causes it?
3) What are its symptoms?
1) Temporal arteritis (Giant Cell Arteritis)
2) The cause of the blood vessel inflammation is unknown; maybe autoimmune?
3) Headaches, jaw pain, vision loss, fever, and fatigue
1) What 3 arteries arise from the external carotid artery?
2) What 2 arteries arise from the internal carotid artery?
1) External: Occipital, posterior auricular, and superficial temporal arteries
2) Internal: Supratrochlear and supra-orbital arteries
Do arteries of scalp and face anastomose?
Yes, they anastomose freely with each other
1) What is the primary vein that drains the face?
2) Do facial veins drain anastomosis? Elaborate.
3) What vein drains the cranial sinuses?
1) Facial vein
2) Variable, frequent anastomosis between internal/external jugular vv.
3) Internal jugular vein
1) What area doesn’t have lymph nodes? What is the exception?
2) Where does lymph drain into? Name each place and where they’re located.
1) No lymph nodes in scalp or face except for parotid/buccal region
2) Lymph drains into superficial cervical ring of nodes, which are: Submental, submandibular, parotid, mastoid and occipital nodes
-Located at junction of head and neck; deep cervical along the IJV
What is the one muscle of mastication that’s not supplied by the anterior trunk of the mandibular nerve/ V3?
Buccinator; supplied by CN VII (facial nerve)
Slide 39
1) What artery does CNIII follow? What do they do?
2) What type of innervation controls the constriction muscles of the eye? What else does it do?
3) What does the sympathetic part of CNIII control?
1) Internal carotid and CNIII run together; helps with eye dilation
2) Parasympathetic does constriction muscles of iris and interacts w ciliary body
3) Sympathetic only works on the iris (not ciliary body)
List all of the 6 clinical implications to injury to the infratemporal region
1) Disruption of zygomatic arch, TMJ, mandible
2) Blood loss to region to include teeth, meninges, etc.
3) V3 somatic motor (muscles of mastication)
4) Parasympathetic via Submandibular ganglia to lingual n. to SM and SL salivary glands
5) Special sensory (taste anterior 2/3 of tongue via chordae tympani branch of CN VII)
6) Parasympathetic via Otic ganglion to parotid gland
What two parts of the tongue are mobile?
Body and apex
What are the 2 categories of muscles that control the tongue? Describe each
1) 4 Extrinsic muscles alter position: Originate from bony formations outside the tongue (more anchored to floor)
2) 4 Intrinsic muscles alter shape: Confined to tongue
What control the gag reflex? (afferent and efferent)
1) Afferent (sensory): Glossopharyngeal n. (CN 9)
2) Efferent (motor): Vagus n. (CN10)
1) What allows you to generally sense with the anterior 2/3rds of your tongue? (also name specific branch)
2) What allows you to taste with the front of your tongue? (also name specific branch)
1) General sensation = CN V3; lingual n.
2) Taste = CN VII; tympani nerve
1) Does the tongue’s lymphatics drain bilaterally or unilaterally?
2) What are the lymph nodes of the tongue?
1) Posteriorly and midline area drain bilaterally
2) Lateral and front drain to mental and submandibular nodes; posterior drains to cervical nodes
Where is the submandibular duct?
Opens onto sublingual papilla opposite of 2nd molar
What allows you to sense with the posterior 1/3 of the tongue?
1) General and special sensory = CN IX
2) Minor contribution from CN X
List the 5 branches of the external carotid artery that supply the face
1) Lingual a.
2) Facial a.
3) Occipital a.
4) Posterior auricular a.
5) Maxillary a
What two arteries that supply the face don’t originate from the external carotid? Where do they come from?
Supratrochlear and supra-orbital arteries are from internal carotid branches
What two arteries of the face can you palpate the pulses of?
Facial arteries and temporal arteries
What supplies the 4 muscles of mastication?
The anterior trunk of the mandibular nerve (V3)
What sinuses make up the paranasal sinuses? List each and whether they’re paired or unpaired
Frontal: Paired
Ethmoid: midline/paired
Sphenoid: midline
Maxillary: paired
1) What nerve innervates the frontal sinuses?
2) What sections of ethmoid sinus cells drain to the middle meatus? What other sinus drains to the middle meatus?
3) What section(s) of the ethmoid sinus drain to the superior meatus?
1) CN6
2) Anterior and middle; maxillary sinus [via maxillary osteum]
3) Posterior
1) Where are the sphenoid sinuses?
2) Do they open into the nasal cavity?
1) Occupy the cavity in delicate sphenoid bone, drain into. 2) No real opening into the nasal cavity.
What is the rich plexus where all the arteries supplying the septum anastomose? What is the clinical significance of this area?
Keisselbach; profuse epistaxis (nosebleeds)
What nerves innervate the nose? (2)
1) Posterio-inferior ½ to 2/3 of cavity is primarily: CN V2 (maxillary n.)
2) Anterior superior cavity (both septum & lateral wall) is primarily: anterior ethmoidal nerves from CN V1 (ophthalmic n.)
True or false: Mucosa of the oral cavity is continuous with the gingiva
True
Where can you find gingiva?
Around the neck of teeth
True or false: There’s both ipsilateral and contralateral drainage of cheeks, lips, and chin lymphatics
True
True or false: infections don’t easily spread from one side of the face to another
False; infections and cancers can spread easily because there’s both ipsilateral and contralateral lymphatic drainage
What covers the roots of teeth?
Cementin
Describe the path of V3 through the lower face
Into mandible at mandibular foramen; provides alveolar nerves
Then comes out mental foramen for skin
Where is lidocaine placed to numb an entire side of the bottom teeth?
V3
1) What does the hard palate separate?
2) What does the soft palate separate?
1) Oral cavity from nasal cavity
2) Oral cavity from nasopharynx
Where are the lingual tonsils found?
Posterior 1/3 of tongue
1) What is the soft palate?
2) What is it made of?
3) How is it attached?
1) Movable posterior 1/3rd of the palate
2) Mainly muscular
3) Palatine aponeurosis; attached to hard palate anteriorly
What does the soft palate do?
Assists in swallowing and prevents bolus entering nasal cavity (by moving/ closing while swallowing)
Which cranial nerve provides:
1) Motor innervation for tongue protrusion?
2) Taste sensation?
3) Somatic sensory innervation to the oral cavity?
1) CN 12
2) CN 7 chordae tympani
3) CN V3 (lingual n.)
1) Where are the sphenoid sinuses?
2) Do they open into the nasal cavity?
1) Occupy the cavity in delicate sphenoid bone, drain into. 2) No real opening into the nasal cavity.
What is the rich plexus where all the arteries supplying the septum anastomose? What is the clinical significance of this area?
Keisselbach; profuse epistaxis (nosebleeds)
What nerves innervate the nose? (2)
1) Posterio-inferior ½ to 2/3 of cavity is primarily: CN V2 (maxillary n.)
2) Anterior superior cavity (both septum & lateral wall) is primarily: anterior ethmoidal nerves from CN V1 (ophthalmic n.)
True or false: Mucosa of the oral cavity is continuous with the gingiva
True
Where can you find gingiva?
Around the neck of teeth
True or false: There’s both ipsilateral and contralateral drainage of cheeks, lips, and chin lymphatics
True
True or false: infections don’t easily spread from one side of the face to another
False; infections and cancers can spread easily because there’s both ipsilateral and contralateral lymphatic drainage
What covers the roots of teeth?
Cementin
Describe the path of V3 through the lower face
Into mandible at mandibular foramen; provides alveolar nerves
Then comes out mental foramen for skin
Where is lidocaine placed to numb an entire side of the bottom teeth?
V3
1) What does the hard palate separate?
2) What does the soft palate separate?
1) Oral cavity from nasal cavity
2) Oral cavity from nasopharynx
Where are the lingual tonsils found?
Posterior 1/3 of tongue
1) What is the soft palate?
2) What is it made of?
3) How is it attached?
1) Movable posterior 1/3rd of the palate
2) Mainly muscular
3) Palatine aponeurosis; attached to hard palate anteriorly
What does the soft palate do?
Assists in swallowing and prevents bolus entering nasal cavity (by moving/ closing while swallowing)
How are the palates innervated with sensory nerve fibers?
Branches of CN V2 (maxillary n; foramen rotundum) (that pass through pterygopalatine ganglia)
What two nerves supply the palates with motor fibers?
1) CN V3: Tensor veli palatini (forms palatine aponeurosis)
2) Pharyngeal plexus from vagus n. CN X: All other (motor) muscles of soft palate (& much of oral pharynx)
1) What nerve does the pharyngeal plexus of nerves come from?
2) What does this nerve do?
1) Vagus n.
2) Acts as motor arm of GAG reflex
True or false: Only way CNV conveys motor is via V3, mandibular n., (foramen ovale)
True
1) What term do you use to refer to both ears?
2) What term do you use to refer to the left ear?
3) What term do you use to refer to the right ear?
1) AU(bilateral)
2) AS (left)
3) AD(right)
What are the 3 parts of the external ear?
1) Auricle (Pinna)
2) External acoustic meatus of Auditory Canal (EAC)
3) Tympanic membrane (TM) (separates outer and middle)
What two nerves provide primary innervation to skin of auricle?
1) Great auricular n.
2) Auriculotemporal n. (CN V3)
What two nerves have a minor contribution to innervation of skin of auricle?
1) CN7
2) CN10
What two nerves innervate the auditory canal and external TM?
CN V3 & CN X
What does it mean if the tympanic membrane is in a neutral position?
The pressure is equal between the middle ear and outside
What are the two openings of the middle ear?
1) Posterosuperior with mastoid antrum (i.e. to mastoid air cells)
2) Pharyngotympanic tube (aka Eustachian tube)
What is found within the middle ear/ tympanic cavity? (4 things)
1) Auditory ossicles
2) Tendons of stapedius and tensor tympani m.
3) Chorda tympani n. (br. of CN VII )
4) Tympanic plexus of nerves
Is the carotid plexus sympathetic or parasympathetic?
Sympathetic
1) What is the stapes (stirrup)?
2) How are sound waves converted from air to mechanical force?
1) Base or footplate occupies the oval window
2) At TM through ossicles
What allows for 10x vibratory amplification in the middle ear?
Base of stapes is considerably smaller than TM
Two muscles of middle ear slide 43
1) What do the two muscles of the middle ear collectively do?
2A&B) Name the two muscles of the ear, describe what each does, and what each is innervated by
1) Resist or dampen movement of auditory ossicles
2a) Tensor tympani: Inserts into handle of malleolus
-CN V3
2b) Stapedius: Pyramidal eminence that inserts onto stapes
-CN VII (nerve to stapedius)
What equalizes pressure between the middle ear cavity and external atmosphere?
Eustachian tube; opens into nasopharynx
What does the vestibulocochlear organ do? (2 things)
Sound and balance
What are the two labyrinths of the inner ear? Describe each
1) Boney labyrinth: fluid filled space of the surrounded by otic capsule
2) Membranous labyrinth: sacs and ducts suspended in the boney labyrinth
What are the two parts of the membranous labyrinth? What does each contain?
1) Cochlear labyrinth
-Cochlear duct
2) Vestibular labyrinth
-Utricle and saccule
What are the 3 symptoms of Meniere’s disease (CN7)? Are these bilateral or ipsilateral?
1) Tinnitus
2) Vertigo
3) Hearing loss
-Often unilateral symptoms
What is an acoustic neuroma? Are its symptoms bilateral or ipsilateral?
1) Peripheral lesion (cerebellopontine angle) of CN7
2) Ipsilateral symptoms
1) What two muscles open the eyelid?
2) What innervates these?
1) Levator palpebrae superioris and superior tarsal mm. opens lid
2) CN 3 somatic and visceral motor
When the sclera of someone’s eye becomes red, what is occurring?
Subconjunctival hemorrhage
True or false: the lacrimal gland is above the rim of the orbit and can’t usually be palpated
True
1) What do the lacrimal canaliculi terminate as? What do they lead to?
2) What do they do?
1) The lacrimal punctum (openings of canaliculi); lead to lacrimal lake w papillae [elevation in eyelids].
2) Convey fluid to nasolacrimal duct [then goes to nasal cavity]
1) What leads to the nasolacrimal duct?
2) Where does it drain?
1) Lacrimal sac
2) Into nasal cavity into inferior meatus (lateral to the inferior concha)
Where is the apex of the orbit?
Optic canal in the lesser wing of sphenoid
What produces aqueous humor?
Ciliary body
1) What is periorbital (pre-septal) cellulitis?
2) Where does venous blood here flow?
1) A skin and soft tissue infection around that eye that is anterior to the orbital septum
2) Into the cavernous sinus
1) What is orbital cellulitis?
2) What can cause it?
3) How is it diagnosed?
4) What are some complications it can cause?
1) Infection of the orbital tissue posterior to the orbital septum.
2) An external focus of infection (e.g., a wound), infection that extends from the nasal sinuses or teeth, or metastatic spread from infection elsewhere.
3) CT/MRI
4) Can become an orbital abscess, which can easily become a subperiosteal abscess, which can become cavernous sinus thrombosis
1) What is the limbus?
2) How large is it, what color, and what does it contain?
1) Angle formed at junction of sclera and cornea
2) 1mm, grey, with numerous capillary loops to nourish the cornea
1) Name 2 attributes of the cornea.
2) What two things keep it moist?
1) Transparent, avascular
2) Bathed in lacrimal fluid and aqueous humor on surface
What are the 3 parts of the fibrous layer of the eyeball?
Sclera, limbus, and cornea
1) What nerve provides sensory innervation for the corneal touch reflex?
2) What provides motor innervation for the corneal reflex?
1) CN V1 (afferent)
2) CN 7 (efferent)
What are the 3 parts of the vascular layer of eyeball?
1) Choroid (uveal tract)
2) Ciliary body/processes (involved w aqueous humor and fibers)
3) Iris/pupil
1) What is the choroid?
2) What does it do? Where is it attached?
3) What is it continuous with?
4) What does it cause? [hint: red]
1) Vascular bed between sclera and retina
2) Nourishes retina; attached to retina’s pigmented layer
3) Continuous anterior with ciliary body and iris
4) Red reflex in infant
1) What part of the ciliary body is constricted? By sympathetic or parasympathetic?
2) What part of the ciliary body is dilated ? By sympathetic or parasympathetic?
1) Parasympathetic constricts sphincter papillae m,
2) Sympathetic dilates pupil dilator pupillae
1) What does ciliary body provide attachment for? How? What does this allow for?
2) What does it fold on? What does this form and what does that do?
3) Where does it get its innervation from?
1) The lens via zonular fibers; allows for fine focus & accommodation
2) On internal surface of body; ciliary process, secretes aqueous humor
3) Parasympathetic from ciliary ganglia (from CNIII)
Are ciliary ganglia sympathetic or parasympathetic and motor or sensory? What do they do?
Parasympathetic motor ganglia; allow for constriction of the iris, pupil, and accommodation
1) What does the iris control?
2) What innervation causes it to constrict the pupil?
3) What innervation causes it to dilate the pupil?
1) Aperture (pupil) for light regulation
2) Parasympathetic via ciliary ganglia to sphincter pupillae
3) Sympathetic to dilator pupillae
What cranial nerve parasympathetically stimulates the iris? How?
CN III; postsynaptic fibers from ciliary ganglia
What two nerves are involved in pupillary response?
1) CN II (afferent/ sensory)
2) CN III (efferent/ motor)
What are the two parts of the optic part of the retina? What does each do?
1) Neural layer: sensitive to visual light
2) Pigment layer: absorbs light, reduce scatter
What are the two parts of the retina?
1) Optic part
2) Nonvisual part
1) What is the nonvisual part of the retina?
2) What does it extend anteriorly over?
1) Anterior extension of pigmented layer of retina
2) Ciliary body and iris
What is the ocular fundus?
Part of eye light strikes when entering eye; what you can visualize during fundoscopic exam
1) What happens at the optic disc/papilla?
2) Why is this location unique?
1) Optic n. enters and radiates to periphery
2) No receptors; our vision’s blind spot
What is lateral to the optic disc? What does it do?
Macula/fovea; specialized for acuity vision
1) What is at the center of the macula? What is this in our vision?
2) What is unique about the center of the macula?
1) Fovea centralis; area of most acute vision
2) Fovea lacks capillary network visible elsewhere deep to retina
What are the important parts of the ocular fundus?
1) Optic disc/papilla
2) Macula/fovea
Where does most refraction of the eye occur?
Cornea
What 5 parts of the eye are reflective?
1) Tear film
2) Cornea
3) Aqueous humor
4) Lens (accommodation)
5) Vitreous humor
What is the pathway of light from the environment to the retina? (8 steps)
1) Environment
2) Cornea
3) AC (aqueous humor)
4) Through pupil
5) PC (aqueous humor)
6) Lens
7) Vitreous
8) Retina/optic nerve
Aqueous humor:
1) Where is it produced
2) Where does it flow through?
3) What does it do?
1) By ciliary process in posterior chamber
2) Flows thru pupil into anterior chamber
3) Nourishes lens and cornea