Q5 - Optho, ENT, Derm Flashcards
Which bone gets eroded with ethmoid sinusitis? Pathogens then spread
Lamina paparatia - medial wall of the orbit.
Valve of Hasner - “one way” valve for tears.
CN 7 “hooks the eyes closed” and CN 3 is like a column keeping it open.
CC bill of 7000 you close your eyes because you don’t want to look
CC bill of 3000 you open your eyes to look because you can’t believe it!
Most common fracture of the eye bones?
Orbital floor
Oculo-cardiac reflex
Indications for urgent repair of the orbit (after trauma)
Occulo-cardiac reflex
Muscle entrapment.
“5 and dime reflex”
CN 5 is connected to vagus somehow, so when muscles of the eye are pulled on, your HR can drop.
What muscle could be damaged with a superior eye lid lac?
Levator Palpebral.
What is obstructed in Peds nasolacrimal duct obstruction?
Usually ________ (congenital/acquired)
Prognosis?
Valve of hasner.
Congenital.
Self limiting by 1 year
What is epiphora?
Acquired nasolacrimal duct obstruction (valve of Hasner)
Infection, trauma.
What causes retrobulbar hemorrhage?
Prognosis?
Trauma - punch in the face.
Anesthesia needle to retrobulbar space.
Pressure builds - assess function (CN 2)
Perform a lateral Canthotomy and Cantholysis.
Orbital compartment syndrome - cause?
Treatment?
Burns
Canthotomy+Cantholysis.
Positive Sidel test means what?
Globe rupture. Where the intra ocular fluid oozes out and washes away the flouriscene.
Globe rupture? What do you do?
Foxshield
Abx Moxifloxacin - 400mg z1
Radio graphic studies (CT Orbits w/wo contrast) check for FOB.
Tetanus.
Retinoblastoma - deets!
Presents before age 4
60% Unilateral
15% germline mutations
RB1 gene on chromosome 13 = TSG check point for cellular growth cycle at G1 check point “2-hit hypothesis”
45% chance of passing on the gene due to 90% penetrance of gene.
2-hit hypothesis
If the first mutation is a germline mutation (sperm or egg), then they only need 1 more mutation to cause the cancer
If the person does not have a germline mutation, then it takes 2 mutations for them to get cancer
LR6 SO4
Congenital CNIV (Trochlear) palsy
Looking straight, affected eye may rise up a little
Adducting affected eye - double vision. (Upshot with lateral gaze away from affected eye-ADduction)
CN VI abducens nerve palsy.
More common in adults/peds?
No ABduction in affected eye (LR6SO4)
RARE in peds, most common in Adults with vascular problems - due to micro vascular insult.
MS, neoplasm, infiltrative cause.
Peds congenital
Look up pics!!
Inter nuclear Ophthalmoplegia (INO)
Ipsilateral adduction deficit
On attempted base to contra-lesional side, abducting eye has horizontal gaze evoked nystagmus
Adults: MS or stroke
Peds: Neoplasm.
CN III slide with pupil sparing or pupil involving.
“Down and out” of affected eye with PTOSIS
Pupil sparing = ischemic
Pupil involving = PCA aneurysm.
Horner syndrome
Injury to SNS.
Ipsilateral ptosis, no pupil constriction, flushing
1st order = ?
Pancoast tumor (2nd order)
Carotid dissection (3rd order)
1st order is tumor of hypothalamus, brainstem or spinal cord
2nd order = tumor of mediastinum, thoracic outlet or thoracic spinal cord
3rd order = superior cervical ganglion, internal carotid dissection, cavernous sinus.
Two common causes of Horner’s syndrome.
Test for Horner’s in a very ________ room.
Dark.
Eyes are already dilated, and so there will be more of a change in constriction.
What’s the difference between a corneal abrasion and a globe rupture with the dye?
Corneal abrasion just stays in one place and lights up. Globe rupture has fluid running out so it will wash the dye away like a trail (sidel).
What is the treatment for corneal abrasion?
Abx.
Contact lens wearers - at risk for pseudomonas infection which can eat through the lens very quickly.
Moxi for contact lens wearers or vegetative injury
Who is more prone to subconjunctival hemorrhage?
Old ladies on blood thinners.
Tx of subconjunctival hemorrhage
2 weeks - artificial tears.
Coughing, valsalva.
Hyphema caused by (blunt/penetrating) injury
Blunt.
Where is a hypema located?
In the anterior chamber.
What things can cause spontaneous hyphema?
SCD, diabetes, coagulopathies, blood thinners.
DC instructions for hyphema?
Return for close f./u due to risk of re-bleed in 7-10 days.
Difference between glaucomas:
Open angle
Angle closure/narrow angle
Open angle - blockage of trabecular mesh network even in setting of adequate space for drainage. Inherited. Blindness with few preliminary symptoms - hours or days!
Angle closure - iris presses agains cornea blocking flow, and the pressure behind it bows the iris out to block the trabecular mesh network. Pain and visual disturbances. Immediate treatment!
Pinhole occluder - if this corrects the vision, then the problem is with the lens, not the retina.
(If patient c/o not seeing well).
VEGF injections DM related macular degeneration of the eye.
Vitreous detachment - 90% go unnoticed or with no symptoms.
If retinal traction or tear involved, THEN there is an issue. Save the retina!
What causes a vitreous detachment?
Aging. It does not reattach.
Causes of nasoairway obstruction
Deviated nasal septum, bilateral inferior turbinate hypertrophy (BITH)
Nasal valve collapse
Chronic sinusitis
Allergic rhinitis
Nasal mass.
What part of the nose senses airflow?
The “valve” over the middle turbinate.
Polyp looks like a “water balloon”