Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Bloc J - Neuro > Oct18 M3-Anatomy_Orbit and Nose_Notes > Flashcards

Oct18 M3-Anatomy_Orbit and Nose_Notes Flashcards

1
Q

(dnm) intraocular mm fct

A

constrict or dilate pupil + change shape of lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

orbit charact

A
  • cone shaped
  • triangle in the back
  • wall in between 2 orbits
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

other cavities in face

A
  • paranasal sinuses (at least 4 of them, 2 on each side. 1 medial sup to orbit and 1 lat inf to orbit). are little pockets). open in the nasal cavities
  • 2 nasal cavities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

coronal cut of orbit charact

A
  • cavity on top = cranial cavity
  • midline plate = cribriform plate where olfactory n. sits
  • orbital fissure in the back
  • optic canal = small hole medial to orbital fissure where optic n passes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

charact of bone around orbit

A
  • diff thicknesses all around
  • floor = thin layer of bone (bc pocket of empty bone (air circulating) underneath it, called the maxillary sinus). easily breakable bone, thin
  • roof = thicker bc of thick frontal bone. so thick you have small cavities developing above orbit, called frontal sinuses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

lobotomy done how

A

remove part of frontal lobe for behavioral tx by going through orbit, breaking roof and reaching frontal lobe of brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

orbit content

A
  • lot of fat (70%)
  • eyeball
  • optic n. connecting to eyeball in the back
  • extraocular muscles (levator palpebrae superioris m. for upper eyelid elevation + 6 mm for moving eyeball)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

extraocular muscles moving the eyeball

A
  • sup rectus = elevate
  • inf rectus = depress
  • lat rectus = abduct eyeball (move lat)
  • medial rectus = adduct
  • inf oblique (start on medial wall and insert lat inf, coming from underneath medially)
  • sup oblique (start on medial wall and insert lat sup)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

fct of inf oblique m.

A
  • when looking straight, rotate eyeball laterally (counterclockwise) if the head tilts to maintain the visual field. called EVERSION (lat rotation)
  • when eye adducted, elevate it by doing the eversion (so can look medial up)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

fct of sup oblique

A
  • like inf oblique when looking straight, but turning clockwise. called INVERSION (medial rotation). stroke involving this m = pat comes in with head tilted
  • when eye adducted, depress it by doing the inversion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

sup oblique m. trajectory

A
  • comes from medial wall of orbit
  • passes in trochlea (piece of bone, cartilage)
  • one muscle belly before trochlea and one after
  • 2nd ones does the inversion
  • insert on lat side off eyeball
  • supplied by trochlear n.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how to test fct of eye muscles

A

H test. move fingers in a H shape in front of pt eyes. each direction = specific mm involved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

orientations of muscles and their origin in the orbit (what explains special fcts of sup oblique and inf oblique mm)

A
  • the orbit is not perfectly AP and rather goes posterior = medial to anterior = lateral
  • the eyeball axis however is perfectly AP
  • bc of this diff, the muscles don’t come from back of eyeball but from medial wall of orbit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

look up lat = what muscles

A
  • lat rectus

- sup rectus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

look down lat = what muscles

A
  • lat rectus

- inf rectus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

look up medial = what mm

A
  • medial rectus

- inf oblique (because sup rectus is not aligned with AP axis of eyeball anymore but inf oblique now is)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

look down medial = what mm

A
  • medial rectus
  • sup oblique (same reason. inf rectus not aligned with AP axis of eyeball anymore but sup oblique now is bc of its 7 shape bc of trochlea)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

CNs moving the eyeball

A

III, IV and VI

19
Q

IV (trochlear n) to what m

A

superior oblique

-short trochlear n. medially directly diving in sup oblique

20
Q

VI (abducens) to what m

A 
lateral rectus (abducens n. is the name bc lateral rectus abducts the eye)
-small n. on surface of lat rectus
21
Q

III to what m

A

all others

  • medial rectus
  • inf rectus
  • sup rectus
  • inf oblique
  • between sup rectus (inf) and levator papebrae superioris (sup) in middle of orbit*
22
Q

branches of V1 relating to the orbit

A

note: V1 and V2 are mainly sensory. V3 is motor
- lacrimal nerve (branch of V1) = lat wall, over lat rectus, to lacrimal gland (so near abducens n.)(sensation of gland fct + SS and PSS inn to control it)
- frontal nerve (branch of V1) = midline of orbit, sup to all mm. splits in ant part of orbit
- supraorbital n. (branch) of frontal nerve (V1 branch) more laterally: for surface of eyeball + skin of forehead
- supratrochlear n. (branch) of frontal n. (V1 branch) more medial: inn. space between two eyebrows

23
Q

summary of nn in orbit

A

medial to lat

  • trochlear n. (CN IV) to sup oblique
  • supratrochlear n. (branch of frontal n., branch of V1)
  • frontal n.
  • supraorbital n. (branch of frontal n., branch of V1)
  • oculomotor n. (CN III) to 4 other extraocular mm
  • abducens n. to lat rectus
  • lacrimal n. (branch of V1) to lacrimal gland
24
Q

how to determine what the problem is if notice that one eye is deviated when pt looks straight

A

deviated eye is bc of unopposed action of a muscle. so problem in the opposite muscle

25
Q

one eye looking straight + other deviated medially dx

A

abducent nerve palsy

-disabled lateral rectus (unopposed adduction)

26
Q

one eye looking straight + other deviated medially up dx

A

trochlear n. palsy

-disabled sup oblique m. (unopposed inf oblique eversion)

27
Q

one eye looking straight + other deviated lat down dx

A

complete oculomotor palsy

  • sup rectus, inf rectus, medial rectus and inf oblique disabled
  • unopposed lat rectus and sup oblique
28
Q

lacrimal apparatus

A
  • lacrimal gland superolat (for lubrication over all conjunctiva = epith of eyeball) in the eye. produces tears then drained in system of ducts
  • canaliculi for sup and inf eyelides (medially in orbit)
  • lacrimal sac (medially between orbit and nose) travels in bone to the nose (nasal cavity)
  • drains in nose
  • no valves in the lacrimal apparatus*
29
Q

problem related to no valves in lacrimal apparatus

A

fluid can go back up, high infection risk

30
Q

anterior and nasal apertures def

A
  • opening of nostrils in the front (can collapse)

- opening of nasal cavity in the back (nasal CHOANAE) into the nasopharynx (can not collapse bc formed by bone)

31
Q

why useful that nasopharynx connects to mouth and nasal cavity?

A

can put mirror in back of mouth and look at nasal cavity from the back, check for obstruction, infection

32
Q

name of chin bone

A

maxilla (top of upper teeth medially, the palate of the mouth)
-palate separates nasal cavity from oral cavity

33
Q

gap in maxilla where air can circulate

A
  • maxillary sinus
  • bacteria can accum in these sinuses when we breathe
  • the ethmoid bone and the inferior nasal concha are 2 plates of BONE covering the nasal cavity from the maxillary sinus
34
Q

diff between the 3 nasal concha

A
  • sup and middle nasal concha are plates coming off the ethmoid bone
  • the inferior nasal concha is a separate bone by itself
  • ALL 3 COVER OPENING of nasal cavity into maxillary sinus*
35
Q

concha physiology

A
  • create little air spaces for air circulation so also called nasal turbinates (bc turbulence to create warm ir from contact with blood vessels and epith on concha)
  • epith of nasal cavity (covering concha) can get inflamed = stuffed nose, takes too much space, hard time to breathe bc nasal cavity is small (packed with bony processes and epith)
36
Q

2 fcts of nasal conchae

A
  • separate nasal cavity and maxillary sinus

- warm and humidify inhaled air

37
Q

paranasal sinuses other than maxillary sinus (below eyes, lat to bottom nose)

A
  • frontal sinuses (pockets in frontal bone at roof of orbit medially)
  • ethmoid cells (little cavities inside ethmoid bone). medial to eyes, lat to top nose
  • sphenoidal sinus (big cavity under cav sinus)
  • ALL COMM WITH NASAL CAVITY*
  • all these cavities grow with age so infection becomes more likely*
38
Q

nasal septum and palatine bones def

A
  • nasal septum = midline sep of 2 nasal cavities

- palatine bones = bone of palate. maxillary sinus above it. dentists are first to see maxillary sinus infection

39
Q

where is the opening of sphenoidal sinus into nasal cavity

A

sup to superior concha

40
Q

what openings are underneath the middle concha

A
  • frontal sinus opening
  • maxillary sinus opening
  • ethmoidal bullae (openings of ethmoidal cells, small holes)
  • so most openings underneath the middle concha*
41
Q

what is the semilunar hiatus

A

little groove underneath the middle concha (so relates to maxillary sinus, frontal sinus and ethmoidal bullae) where frontal sinus opens into maxillary sinus

42
Q

how surgery for pit tumor is done using the paranasal sinuses

A
  • pit gland sits sup to sphenoidal sinus
  • can access this sinus from the nose
  • break posterior wall of sphenoidal sinus to access pituitary
43
Q

clinical relevance of paranasal sinuses

A

infections

44
Q

CT image with opacity in maxillary sinus, no prob of nasolacrimal duct, nasal cavity not obstructed, no fracture or bone damage: dx

A

infection of maxillary sinus

Bloc J - Neuro (60 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions