Head and Neck Flashcards
congential toricollis-age of onset, presentation, mc causes (2), treatment (2)
2-4 weeks, child prefers to hold head tilted to one side (tilted towards and rotated away from SCM damaged), mc result of malposition of head in utero or birth trauma (sternocleidomastoid muscle injury and fibrosis). treat with conservative therapy and stretching exercises.
recurrent laryngeal nerve- travels with which artery, injured how, results of injury (3)
close approximation to inferior thyroid artery, injured in surgical procedures and can results in laryngeal muscle paralysis,hoarse voice, and dyspnea
ansa cervicalis
loop of cervical plexus that receives contributions from C1, C2, C3. courses deep to the sternocleidomastoid muscle and loops around internal jugular vein. innervated sternohyoid, sternothryoid and omohyoid muscles
course of spinal accessory nerve
exits jugular foramen and courses on top of levator scapulae muscle to innervate the sternocleidomastoid
cleft lip vs cleft palate
frequently occur together, form during 6th week
- failure of maxillary promieneces to fuse with medial nasal prominence (becomes intermaxillary segment)
- PALATINE SHELVES of maxillary promienences fail to fuse with each other or the primary palate (aka intermaxillary segment)
name 3 genes of polyprotein precursors in HIV? what protein do they become
gag, pol, and env
env product is glycosylated gp160 and cleaved in ER and golgi to become gp120 (attach to CD4+ to cell) and gp41 (fusion and entry)
gag- makes p24 a capsid protein
pol-makes reverse transcriptase, aspartate protease, and integrase
how do you use tracheal PO2, alveolar PCO2 and alveolar PCO2 to determine diffusion vs perfusion limited
diffusion-only O2 would be effected b/c CO2 diffuses at a rate 20 times that O2
perfusion-both O2 and CO2 would be abnormal
also with perfusion alvelolar PO2 and tracheal PO2 are close in number
when is O2 diffusion limited? normal tracheal pO2 and alveolar levels?
tracheal PO2 is 150mmh and alveolar PO2 is 104
normally O2 is perfusion limited
diffusion limited occurs during exercise, emphysema, and pulmonary fibrosis
name 3 genetic causes of Downs syndrome
95% caused by trisomy 21
-other less common causes are unbalanced Robertsonian translocations (46 chromosomes with an extra arm of 21 attach to another chromosome) or mosaicism (pts with two cell lines-one normal and other with trisomy 21)
pterion-def, art that course deep to this structure, enters where?, branches from, at risk when, bleed can cause?
site where frontal, parietal, temporal, and sphenoid bones meet in skull.
- middle meningeal art
- enters through foramen spinosum
- branches from maxillary
- skull fractures here can cause laceration and epidural hematoma
oseltamivir-def, action (2) treatment,
neuraminidase inhibitor used to treat and prevent influenza A and B
-impairs release of newly formed virions and impairs viral penetration of mucous secretions in respiratory epithelium
Down syndrome characteristics-CNS, head and neck, extremity, cardiac, GI-increased risk of what two diseases as a child and which 1 disease as an adult?
mental retardation, facial dysmorphism, single palmar crease, endocardial cushin defects, duodenal atresia
-increased risk of AML-M7, ALL as a child and increased Alzheimer as an adult
test results in conductive hearing loss (external sounds to innner ear) vs senorineural loss (inner ear, cochleas, or auditory nerve problem)
- bone>air conduction: abnormal Rhinne (in affected ear) and Weber localizes to affected ear (b/c out ear problems masks outside noise and inner ear can hear sound louder)
- air>bone: normal Rhinne and Weber localizes to unaffected ear (b/c inner ear is fine)
reasons for conductive vs sensorineural loss
- Ceruem impactions, cholesteatoma, otoscelrosis, external or middle ear tumors, tympanic membrane rupture, severe otitis media
- Meniere’s disease, acoustic neuroma, presbycusis, ototoxic drugs (aminoglycosides)
calcification of internal carotid artery can lead to what visual field defect
aneurysm or atherosclerotic calcification of the internal carotid art can laterally impinge on the optic chiasm causing nasal hemianopia by damaging uncrossed optic nerve fibers from temporal portion of ipsilateral retina
calcification of internal carotid artery can lead to what visual field defect
aneurysm or atherosclerotic calcification of the internal carotid art can laterally impinge on the optic chiasm causing nasal hemianopia by damaging uncrossed optic nerve fibers from temporal portion of ipsilateral retina
occlusion leads to which visual defect
- posterior cerebral art
- anterior choroidal art
- middle cerebral art
- retinal art or central retinal vein
- homonymous hemianopia with macular sparing (macula is spared due to collateral blood from the middle cerebral art)
- optic tract (homonymous hemianopia )
- optic radiations (homonymous hemianopia)
- optic nerve
major adaptive immune mechanism that prevents reinfection with influenza virus
anti-hemagglutin IgG antibodies in circulation and mucosal anti-hemagglutinin IgA antibodes in nasopharynx
Edwards vs Patau’s Syndrome
both have rocker bottom feet
- Edwards (47,XX +18) has overlapping fingers and clenched hands, low set ears
- Patau’s (trisomy 13 )cleft lip and palate, polydactyly and omphalocele
mucormycosis is caused by which bacteria? presentation? pt pop? histo?
- rhizopus, mucor, or absidia species
- paranasal sinus involvement
- diabetic immunosuppressed pt
- fungi form in broad nonseptate hyphae that branch at right angles
Turner’s presentation (extremeties, cardiac, renal)
-45,XO; lymphedema of varied intensities (hands, feet, hydrops fetalis), coarctation of aorta, horseshoe kidney
47,XXX presentation
usually clinically silent, slightly decreased IQ scores
skin flushing an mydriasis are effect from what receptor blockade. name 5 drugs that are important to know.
- antimuscarinic drugs
- atropine, TCA (i.e. amitriptyline), H1 receptor antagonists (i.e diphenhydramine), neuroleptics, antiparkinsonian
rash of rheumatic fever
-after 1-2 days it begins on neck, armpits and groin as a scarlet spots or blotches (like a boiled lobster)
-then is becomes more widepread like sunburn with goose pimples “sandpaper like”
-finally cheeks become flushed with pale area around mouth-circumoral pallor
lastly (at end of 1st wk) desquamation begins (esp armpits, groin, tips of fingers and toes)
how to treat acute C. diphtheriae? which is more important? why?
- diptheria antitoxin (give antibodies to toxin)-passive immunity and most important
- penicillin or erythomycin-not as important b/c it’s endotoxin not bac that causes damage (esp to brain and cardiac tissue)
- DPT vaccine- active immunity
rate limiting step in acyclovir activation? not viral protease?
not protease but viral thymidine kinase
which antidepressant can cause symptoms similar to atropine overdose
- TCAs have antimuscarinic side effects
- hot as a hare, dry as a bone, red as a beet, blind as a bat, and mad as a hatter
which strand of H. flu causes meningitis? which causes sinusitis?
- type B
- non-typable
mc cause of bac causes of acute otitis media, sinusitis and bacterial conjunctivitis
-streptococcus pneumoniae, NON-typable H. influenzae, and Moraxella catarrhalis
-how to viruses with double stranded DNA exchange material? not reassortment b/c?
- genome recombination-gene exchange that occur through crossing over of two or more double stranded DNA molecules
- this occurs with mixing of viruses with segmented genome segments
which viruses causes pharyngoconjunctival fever that classically occurs in small outbreaks among individuals living together in close quarters?
Adenovirus
-Calcivirus is the family for norovirus that causes viral gasteroenteritis
which nerve is at risk of injury during thyroidectomy? why? what does it innervate?
- external branch of superior layngeal nerve
- close proximity to superior thyroid art and vein
- cricothyroid muscle
what is innervation of superior laryngeal nerve
two nerves branch from the SLN
- the external branch innervates the circothyroid muscle
- the internal branch does not innervate muscle and provides sensory innervation above vocal cords
what is innervations of recurrent laryngeal nerve?
-all laryngeal muscles (thyroarytenoid, lateral circoarytenoid, posterior cricoartynoid, aryepiglotticus)
retinal art occlusion vs amaurosis fugax
- painless sudden, PERMANENT monocular blindness. pale retina with “cherry red” macula
- painless, TRANSIENT, monocular vision loss, small emoboius to opthalmic art
Foscarnet vs ganciclovir
both work well against CMV
- F does not require activation by viral kinase
- G does
circothyrotomy crosses which layers?
-skin, superficial fascia (subcutaneous fat and platysma muscle), investing and pretracheal layers of deep cervical fascia, and cricothyroid membrane
name layers of deep cervical fascia
investing, pretrcheal, prevertebral, carotid sheath
where is investing layer of deep cervical fascia and what does it enclose?
-surrounds the neck like a collar, enclocing all deeper parts of neck (sternoidmastoid, trapezius, strap mucles, submaxillay and parotid glands)
where is pretracheal layer of deep cervical fascia and what structures does it enclose?
anterior part of the neck, blend laterraly with carotid sheath
enclosed viscera of neck (thyroids, parathyroids, larynx, trachea, pharynx and esophagus)
where is prevetebral layer of deep cervical fascia and what does it enclose?
- surrounds vertebral column and muscle of spine
- encloses vertebral column, scalene, longus collus, splenius, erector spinae, semipinalis and levator scapulae muscles
carotid sheath layer is where? what structures does it enclose?
- lies lateral to retropharyngeal space, deep to sternocleidomastoid muscle
- carotid artery, IJV and vagus nerve
probenecid
compound that decreases renal clearance of penicillins by inhibiting tubular organic acid secretion systems
how is sound transmitted through ear? where is low frequency sound heard best? high frequency sound?
- sound reaches middle ear by virbation tympanic membrane
- ossicles transmits this vibration to oval window
- oval window causes movement of perilymph in scalavestibuli which is transmitted to scala tympani
- perilymph movement in scala tympani causes flexible basilar membrane to vibrate
- basilar membrane causes movement of cilia hair cells on rigid tectorial membrane
- hairs calls causes depolarization and hyperpolarization leading to nervous impulses
low frequency vs high frequency sound
- base of basilar membrane, closest to oval and round window is best of high frequency sounds
- apex of cochlea near the helocotrema is best for low frequency sounds
perilymph of scala tympani vs scala vestibuli s scala media?
- high concentration of Na in scala tympani and vestibule
- high concentration of K+ in scala media
organisms that cause mononucleosis-like syndromes
-most common?
- CMV, HHV-6, and toxoplasmosis
- CMV is most common
mc presentation of CMV in immunocompetent vs immunocompromised pts?
- competent=mononucleosis
- promized=retinitis, pneumonia, esophagitis, colitis, and hepatitis
which nerves are responsible for efferent and afferent arc of pupilary light reflex?
- CN II afferent limb
- CN II is efferent limb
CN responsible for closing eye vs opening eye?
- open eyelid=CN III
- close eyelid VN VII
pupilary light reflex
impulse is recieved at optic nerve
travels to pretectal nucleus
-spilt nerves traven to edinger-westphal nucleus
-oculomotor nerve transmits message to both ciliary ganglion,
postsynaptic nerve innervates iris sphincter and cillary muscle
Rb mutations leads to an increased risk of? not neuroblastomas b/c?
- sarcomas esp osteoscaroma
- common childhood cancer that arrises from sympathetic nervous tissue most commonly in the adrenals
acute otitis media vs otitis externa?
- H. influen
- P. aeruginosa
presentation of malignant otitis externa? bac that causes it?
-elderly DM pt with ear pain and drainage and granulation tissue
presentation of primary HSV-1 infection vs reactivation?
- primary- fever, vesiculoulcerative gingivotomatitis, and cervical lymphadenopathy
- reactivation- limited perioral blisters, or “cold sores”
abortive viral infection
results in little to no change in host cell and no viral replication
-no cytopathic effects in pt
examples of slow virus infections
- degenerative disorders of CNS
- subacute scleorising panencephalitis and progressive multifocal leukencephalopathy
