Retinoscopy and clinical scenarios
during retinoscopy you observe neutrality through a +0.25 lens on 30 axis and neutrality through -3.00sph lens along 120 axis. If working distance 50cm, what is RE in plus cyl notation?
+0.25 x30 -3.00 x120 becomes -1.75 x30 -5.00 x120 -5.00 +3.25 x120
You are performing retinoscopy, you observe neutrality through +1.25 lens. with streak oriented vertically, neutrality through +2.25 lens when streak horizontal. Your working distance is 67 cm. How would you record the net retinoscopy findings?
+1.25 180 +2.25 090 -0.25 180 +0.75 90 +0.75 -1..00 x090
You are performing retinoscopy and with the streak oriented at 090° you neutralize the meridian with a +1.25 lens. When the streak is oriented at 180° you neutralize the meridian with a +2.00 lens. Your working distance is 50 cm. How would you record the net retinoscopy findings?
+1.25 x180 +2.00 lens x90 becomes -0.75 x180 plano 90 plano -0.75 x090
If you begin performing retinoscopy and immediately see neutrality without any lenses in front of the patient's eyes, what type of refractive error does the patient have?
-2.00 D myopia emmetropia- need to find gross +2.00 hyperopia- more plus than working distance, find +7 for rx+5 myopia- less plus than working find +1.5 for -0.5 myope
You are performing retinoscopy and with the streak oriented at 100° you neutralize the meridian with a -3.00 D lens. When the streak is oriented at 010° you neutralize the meridian with a -4.75 D lens. Your working distance is 67 cm. How would you record the net retinoscopy findings in minus cyl form?
-3.00 10 -4.75 100 becomes -4.5 10 -6.25 100 -4.5 -1.75 x010
case #7 75-year-old male cc: : Blur at distance and near cc lenso: OD -0.75 -0.50 x 180 Add: +2.00 OS -1.75 -0.25 x 180 Add: +2.00 VA: VA (cc @ D): 20/25 OD, 20/20 OS, 20/20 OU VA (cc @ 40 cm): 20/40 OD, 20/40 OS, 20/40+ OU what is re?
0.25D blur at distance OD, 0.75 blur near OU no accom since 75 can be hyperopic or myopic shift of 0.25sph or astigmatism SE 0.25 Myopic OD -0.75 -1.00 x 180 Add: +2.75 OS -1.75 -0.25 x 180 Add: +2.75 OD -1.00 -0.50 x 180 Add: +2.75 OS -1.75 -0.25 x 180 Add: +2.75 Hyperopic OD -0.50 -0.50 x 180 Add: +2.75 OS -1.75 -0.25 x 180 Add: +2.75 OD -0.75sph Add: +2.75 OS -1.75 -0.25 x 180 Add: +2.75
case #6 28yr old female CC: Blurry vision at distance sc OU lenso: OD -0.50sph OS -0.75sph VA (cc @D): OD 20/25+1; OS 20/20+2; OU 20/15-1 VA (cc @N): OD 20/20; OS 20/20, OU 20/16 what is refractive error?
0.25D blur in OD, either myopic shift since no trouble reading or astigmatism (-0.50 -0.50 xaxis) likely -0.75sph OD -0.75 OSsph
case #9 nonbinary 46 cc: Blurry vision at distance sc DVA sc: 20/60-2 OD, 20/40-1+2 OS, 20/20 OU NVA @ 40cm: 20/20 OD, 20/20 OS, 20/20 OU Retinoscopy: OD -1.25sph OS -0.75sph CFF: Restriction sup nasal OD, Restrictions sup temp OS
1.15 D blur OD, 0.75D blur OS
What VA would you expect according to Egger's chart if a patient has the following Subjective Rx? -2.00 sph -0.50 -1.00 x 180 plano -2.50 x 180 +1.00 (age 15) +1.00 (age 70)
20/150 20/50 SE 20/60 SE 20/20 can accomodate 20/50 can't accomodate
case #10 12 yo female cc: hard time reading greater than 15 min CT sc @ D: ≈ 1EP CT sc @ 40cm: ≈ 6EP Retinoscopy: OD +0.25sph OS +0.75sph
DDX: esophoria (not convergence insufficiency bc eso already too converged) (hyperopia normal in kids, if worried about accom issue can do push up amps) to compensate- need divergence, or negative fusional vergence
wet vs dry retinoscopy
Dry= performed without cycloplegic drops, need to fog patient by adding plus lens to non tested eye wet= after cycloplegia introduced, can no longer accomodate ex. cyclopentolate damp= drops that somewhat stop accommodation - e.g., Tropicamide absolute presbyopes, no accomodation, don't need to be fogged
What if I'm having trouble finding neutrality?
Neutrality can fall into a small range ØIf this is the case, it is generally recommended to choose the most plus power needed to neutralize the reflex
case #11 3yo male CT sc @ D: Attempted, could not perform CT sc @ 40cm: ≈ 6XP • Retinoscopy: OD +4.00sph OS +4.00sph risk for amblyopia?
No, only phoria at near isoammetrope, less than +5
retinoscopy with trial frame
Pros: - Easier to fog and measure VA in the "real world" - Reduce proximal accommodation which can occur in the phoropter Cons: - The trial frame is heavy and a little uncomfortable - Can be slow until you have more experience with the loose trial lenses
which of the following least likely to be subjective refraction end point in left eye? -1.5sph -0.75 -1.50 x130 -1.25 -0.5 x180 -1.00 -2.00 x090
all are over minus but D is most minus -1.00 -2.00 x090
along the meridian vs streak oriented
along the meridian- power is where it says streak oriented- must be flipped
ret racks
commonly performed with kids and other patients who cannot sit behind the phoropter - With motion → more plus power needed, black - Against motion → more minus power needed, red i.e., a 20/400 snellen optotype for adults, Start with the right eye and fog the left eye after find ret, this is starting point for subjective using phoropter and VA, or rett over phoropter lenses
case #2 47yr old female cc: vision is blurry at near both eyes sc
constant, year ago, both eyes, over counter readers DDX: presbyopia
working distance
distance between objective lens and examiner Subtract the working distance in diopters from the dioptric value found to neutralize the reflex ex. if neutralized at +2.00 and examiner at 50cm, emmetrope if neutralized at -2.00 will be -4.00 if 67cm power is -1.5
case #4 68yr old male cc: blurry at distance and near cc
doesn't feel confident driving hard time reading, last eye exam 5 years ago, no surgery, glaucoma, amd DDx: refractive error or cataracts, could use pinhole to determine
sleeve down vs sleeve up
down= plane mirror, diverging light up= concave mirror, converging light, reverses movement of light
case #5 36 yr old female cc: eyes are irritated
feels gritty in both eyes, worse at end of day, can see fine at distance and near, no glasses, no trauma amd glaucoma disease DDX: dry eyes
gross vs net retinoscopy
gross= the power of the lens needed to reach neutrality ex. -3.00 lens was needed to reach neutrality net= refractive error after accounting for the doctor's working distance ex. -3.00 but examiner 67cm away, really -4.5
case #3 12 yr old male cc: eyes hurt has headaches
last sep, both eyes, when reading computer, vision clear at distance and near, letters jump around page, helps if covers one eye, no double vision, no trauma, surgery POX: never failed screening, no glasses DDx: convergence insufficiency
Which of the following would you least likely expect in patient with CN3 palsy? anisocoria greater in brightness ipsilateral RAPD ipsilateral ptosis ipsilateral adduction defect ipsilateral accommodation dysfunction
least likely to be RAPD CN3 causes anisocoria greater in brightness ipsilateral ptosis- LPS adduction restriction- bc MR accomodation- pupil can't constrict
fogging
necesssarry to reduce accomodation, fog eye not being tested, will also fog other eye hyperopes- more plus power myopes- plus power or if high myope less minus power
Let's say you measure a 13-year-old patient's Lea acuity to be 5/5 (20/32 optotype at 10 ft) on a vision screening. After performing retinoscopy, you record -1.00 sph as your net retinoscopy result. Does this make sense?
no bc minus one corresponds to 20/50 she shouldn't be able to see 20/32 we are over minusing or subject is accomodating If a patient is accommodating while you performing retinoscopy, you will scope more minus
Retinoscopy
objective test, measures light off the retina, lenses change this reflection until neutralized measures patient's refractive error and accommodation good for nonverbal patients who can't do subjective, no phoropter
retinoscopy recording
only record net, type, measure, corresponding VA Dry Retinoscopy: OD: -2.00 - 1.00 x 180 20/3 OS: -1.50 - 0.75 x 175 20/20 Damp Retinoscopy: OD: +2.50 sph 20/15 OS: +2.00 - 1.00 x 090 20/20-1
the lesion on case #9 is most likely associated with which location? optic tract retinal ganglion cells superior cervical ganglion hypothalamus optic nerve
optic tract- cff restriction in both eyes must be posterior to optic chiasm or occipital lobe if only one eye- ant to chiasm rgc or optic nerve, also be associated with RAPD
You perform retinoscopy at a 50 cm working distance gross lens cross +2.00 x 135 and -2.00x 045 record your net retinoscopy findings in minus-cyl spherocylindrical form
plano -4.00 x135
What if there is no reflex?
probably really far from neutrality or there is corneal opacity
case #8 56 yo male CC: Double vision and droopy eyelid EOMs: OD SAFE; OS Limited adduction/supraduction/infraduction. Abduction intact Pupils - OD 2.5/1.0mm, round, 3+ reactivity, (-) RAPD - OS 4/3.5mm, round, 3+ reactivity, (-) RAPD
ptosis, double vision, eom restriction of MR, IR, IO, pupil smaller in OD, more than 1mm diff in bright and dark conditions is significant, greater in bright PNS issue pupil can't constrict DDX: CNIII palsy
Focault's Principle
refractive state of the eye changes which way light will move (with/against) lenses move the patient's far point to the pupil of the examiner instead of physically moving examiner the examiner is at 50cm or 67cm so they aren't at optical infinity must take this into account ex. with the motion, far point is virtual behind examiner, use plus lenses to bring to examiners pupil instead of moving th examiner farther away
how to determine astigmatism
scope the most plus meridian first, after scoping most plus and neutralizing the other meridian will look against motion (need less plus power) put into optical cross difference gives you cyl ex. scoping vertical find +1, scoping horizontal find +2, once u neutralize +2 if you scope vertical it will look against motion
scoping retinoscopy and astigmatism
scoping vertical meridian (90)= streak is horizontal 180, moving up and down scoping horizontal (180)= streak is vertical 90, moving left and right if there is astigmatism you will see a break
vision screening vs CEE
screening: to detect abnormalities → prioritize high sensitivity ex. VA, brief case history, NPC, NCT, DCT, Bruckner, EOM, Pupil, Ret cee: to diagnosis abnormalities → prioritize high specificity ex. all plus subjective refraction, ocular health eval, functional testing, confrontation fields
static vs dynamic retinoscopy
static= fixating on large non accommodative target, not changing fixation, determines refractive error dynamic= changing fixation, asses accommodation, ex. near target MEM cards, determines accommodative response
case #1 28yr old female what do you ask?
what brings you in today? FOLDARQ pertinent neg= glaucoma, AMD, trauma, cataract famlily history, medications, allergies
with vs against motion
with= use plus lenses, far point of patient is behind examiner, need plus lenses to bring closer, sleeve up will be against, subject can be small myope, hyperope, or emmetrope against= use minus lenses, far point is before examiner in between pt, minus lenses push it back, subject is myope neutrality= fills up the pupil, far point is at examiners pupil, subject is -2 or -1.5 myope
case #12 7 yo male CT sc @ D: Ortho CT sc @ 40cm: ≈ 4 XP Retinoscopy: OD +0.50sph OS +2.00sph risk for amblyopia?
yes, anisometropia greater than +1.00 not strabismic amblyopia
