Try another question from this subject A 36-year-old woman has migraine without aura on 12 days each month. For 4 months she has taken a combination acetaminophen, aspirin, and caffeine product on 16 days each month, often at the first hint of discomfort. Headaches now occur on 22 days each month and frequently begin on awakening. Neurologic examination and funduscopic examination are normal, and she has no fever or recent head trauma.
Which of the following is the most appropriate management plan?
A. Add daily oral sumatriptan B. Discontinue the combination analgesic and initiate migraine preventive therapy C. Obtain emergent noncontrast head CT D. Prescribe oxycodone for severe headache days E. Switch to butalbital-containing analgesic as needed
Choose an answer before revealing the reasoning.
Get one of these every morning · Practice more in the QBank
Ciliary muscle is the switch
Near means round. Far means flat.
Do not memorize the words first. Watch the rope system. Ciliary contraction removes tension from the zonules, so the lens rebounds into a rounder, stronger shape.
Far focus is the rest state.
Ciliary muscle relaxes. Zonules pull tight. Lens flattens. The eye uses less optical power because far light arrives almost parallel.
Far: relax ciliary, tighten zonules, flatten lens.
Starting picture: far object is blurry in myopia.
Focus direction: focal point lands too early, in front of the retina.
Correction: spread the rays with a negative lens.
Near reflex 1 Convergence
Near reflex 2 Miosis
Near reflex 3 Accommodation
Age trap Stiff lens, not weak retina
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Focal point triage
Front, behind, or many.
Refractive errors are not random names. The focal point tells the diagnosis and the correction.
incoming light
cornea plus lens
retina
Myopia: focal point in front of retina
Myopia
Hyperopia
Astigmatism
Myopia: the focus lands too soon.
The eye is too long or the cornea is too curved. Far objects blur because their light focuses in front of the retina.
Negative lens, like -1.75
Positive lens, like +1.50
Cylinder correction or surgery
Pick the correction for the active error.
Myopia Near OK, far blurry
Hyperopia Far OK, near blurry
Astigmatism Multiple focal points
Presbyopia Stiff lens, near trouble
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Lens pathology lab
Displaced or cloudy.
Ectopia lentis is a position problem. Cataract is a transparency problem. Do not let both being "lens disorders" make them feel the same.
Ectopia lentis sorter
Use direction plus body clue. Trauma is common, but the board loves systemic disease.
Tall patient, long arm span, lens is up and out
Marfanoid habitus, developmental delay, lens is down and in
Single displaced lens after blunt eye injury
Tap a clue bundle.
Osmotic cataract bench
The avascular lens survives by diffusion. Trap a sugar alcohol inside it, water follows, and the clear lens turns cloudy.
Glucose
Galactose
Rubella
Glucose
→
Aldose reductase
→
Sorbitol
Diabetes loads glucose into the lens. Sorbitol accumulates because the lens poorly clears it. Water follows, and the lens clouds.
Image anchors
See the lens problem.
Photos anchor the two buckets: a lens out of position versus a lens that has lost transparency.
Ectopia lentis
Position problem: the lens is displaced.
Wikimedia Commons, CC BY-SA 4.0
Congenital cataracts
Transparency problem: the lens is opaque.
CDC PHIL, Public Domain
Rubella cataract
Classic fetal eye clue with deafness and PDA.
CDC PHIL, Public Domain
Board walkthrough
Vignette 1 of 8
Shuffle bank
Next vignette
Keep the buckets separate.
Refractive errors are focal point errors. Ectopia lentis is a lens-position error. Cataracts are lens-transparency errors.
Continue with cranial nerves
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Bone WizardryMEDICAL EDUCATION