Anatomy 2.0 Flashcards
What does this describe: a thick fascial sling that holds the eye just above the floor of the orbit?
suspensory ligament
What is diplopia?
double vision
What may a fractured zygoma lead to due to lowering of the suspensory ligament?
diplopia
What can be damaged in a fracture of the zygoma, resulting in a general sensory deficit of the facial skin?
the infraorbital NVB within the infraorbital canal
What does CNV1 (opthalmic nerve) supply?
the upper eyelid
- the cornea
- all the conjunctiva
- the skin of the root/bridge/tip of the nose
What does CNV2 (maxillary nerve) supply?
the skin of the lower eyelid
the skin over the maxilla
the skin of the ala of the nose
the skin/mucosa of the upper lip
What does CNV3 (mandibular nerve) supply?
the skin over the mandible and temporomandibular joint (apart from the angle of the mandible – supplied by C2,3 spinal nerves)
Action potentials are conducted centrally via which nerve to the trigeminal ganglion, then in which nerve to the pons?
CNV1 (opthalmic branch of trigeminal nerve)
CNV (trigeminal nerve)
The inferior cervical and 1st thoracic ganglia often fuse to form the what?
stellate ganglion
Which presynaptic parasympathetic axons leave the CNS in cranial nerves III, VII, IX & X?
ALL
What do presynaptic parasympathetic axons supply from CNIII?
to the ciliary ganglion
The long ciliary nerves form what?
the first part of the afferent limb of the blink (corneal) reflex
The ciliary nerves supply autonomic axons to control what?
the diameter of the iris (& pupil) & the refractive shape of the lens
What does the the vestibulo-ocular reflex do?
- turns the eyes in the opposite direction to a head movement (to stabilise the gaze on an object during head movements)
What is the oculocardiac reflex?
reflex bradycardia in response to tension on the extraocular muscles or pressure on the eye
Which type of lacrimation is parasympathetic and with is sympathetic?
emotional - sympathetic
reflex (to wash away foreign bodies/clean) - sympathetic
Is getting less light into the eyes parasympathetic or sympathetic?
parasympathetic (eg when asleep)
Is levator palpebrae superioris skeletal or smooth?
BOTH
What is a non-physiologically enlarged pupil?
mydriatic pupil
What drugs might cause a fixed pin point pupil?
opiates
What is the arrangement of sphincter pupillae fibres all around the internal circumference of the iris?
encircling
What is a fixed dilated pupil (blown out pupil) a sign of?
is often a serious pathological sign e.g. of CN III pathology (inhibiting the pupillary constricting action of parasympathetic axons in the ciliary nerves)
What is a non-physiologically constricted pupil called and in what syndrome may it occur?
a miotic pupil
Horner’s syndrome
What are the 3 components of the accommodation reflex?
1.bilateral pupillary constriction (CNs III)
2. bilateral convergence - medial rotation of both eyes (CNs III)
3. bilateral relaxation of the lens
the lens becomes spherical due to contraction of the ciliary muscles (CNs III)
