revision Flashcards
types of phorias
XOP: Convergence weakness (XOP at near), Divergence Excess (XOP at distance), Non-Specific
SOP: Convergence Excess (SOP at near), Divergence Weakness (SOP in distance), Non Specific
L/R Hyperphoria or R/L Hypophoria
Cyclophoria (look @ BV’s)
Incomitant = diagnosed by underlying cause e.g. L hypophoria in 4th nerve palsy
Which way to measure deviation in prisms
ESO = BO
EXO = BI
HYPO = BU
HYPER = BD
Normal PFR
Nr: 35 Dioptres BO -> 15 Dioptres BI
Dis: 15 Dioptres BO -> 5 Dioptres BI
Vertical: 3 BD -> 3 BU
3rd NP muslces
MR, SR, IR, IO
Superior division: SR + Levator Muscle
Inferior Division: MR, IR, IO, sphincter muscle + ciliary muscle
functions of muscles
MR: Adducion
LR: Abduction
SR: Elevation, Intorsion, Adduction
IR: Depression, Exorsion, Adduction
SO: Intorsion, Depression, Abducion
IO: Extorsion, Elevation, Abduction
SOT Bigger @ Nr
Fully Accom SOT, Convergence Excess SOT, Partially Accom (present at all times but increases when accom exerted), Near SOT
SOT bigger @ dist
Distance SOT
SOT same Nr + Distance
Infantile SOT, Acquired (early vs late onset), Acquired with myopia, MicroSOT
XOT bigger @ nr
Intermittent Near XOT
XOT bigger in distance
Intermittent Distance XOT
XOT same Nr + Dist
Intermittent Non-Specific XT, Early Onset XT, Decompensated intermittent XT
critical period + sensitive period
critical = 0-2 years old
sensitive = 2-8/10 years old
types of ambylopia
strabismic, meridional, stimulis deprivation, aniometropic, ametropic
pass mark for logMAR + Kays
logMAR = 0.2
Kays = 0.1
excercises for EXO + ESO
EXO = + fusional vergence
ESO = - fusional vergence
Stereograms ( + = hold card at arms legnth and focus on object between eyes and card) (- = hold card at 33cm, fixate in distance target just above card)
Eso = -‘ve = bar reading (add - or reduce + and read), if BIN can read in front of print, if using one eye, bar will hide text)
Exo at near = smooth convergence (NPC), jump convergence (jump from distant to near target ), Dot card (fix on furthest dot and move to near dot while appreciatign double).
prisms EXO = BO, ESO = BI
post-op diplopia test
-use single letter e.g. P or D
-Will get diplopia if overcorrected after surgery?
DVLA what is driving standard
0.2 Logmar
what prism direction for PFR for ESO + EXO
ESO = BI, EXO = BO
pupils
PERLLA (pupils equally round and responsive to light + accommodation)
RAPD
what diff for lateral incomitance?
5-10 dioptres
diff for A vs V patterns?
V = 15 dioptres diff
A = 10 dioptres diff
convergence vs accom on RAF rule
Convergence = line + dot, go until double then go back and repeat 3 times
Accom = letter chart, go until blurry then go back to first point clear again and repeat 3 times
tilt downwards
deviation size for surgery?
20 dioptres
order of limitations TED
IR, MR, SR, LR
size of amblyopia
mild: 0.2–.3 LogMAR
moderate= 0.3-0.8 logMAR
severe: > 0.8 logMAR
refractive adaptation period
18-22 wks (PEDIG 2012)
Continued improvment unpto 30 weeks (PEDIG 2006)
2 + 1/2 lines improved (Stewart + Motas 2004)
patching moderate ambylopia
2 hrs + near tasks ( = 6 hrs) (PEDIG 2003)
baseline acuity 0.6-0.7, more hours
>7 y/o = 6 hours patching
max time for patching
400 hours , 4 hours per day max
how much improvement patching
120 hours = 1 line improvement (MOTAS)
atropine
blurs around 2-3 lines
moderate amblyopia = daily = weekend atropine
severe ambylopia = still works (PEDIG 2009)
cant use in under 3 y/o
8 minims = 4 weeks
sizes of deviations
minimal: <10 dioptres
small: 10-20 dioptres
moderate: 25-35 dioptres
marked: >40 dioptres
VA measure (start from 5 right at 0.1 line –> 0 right)
each letter = 0.02 so e.g.
0.1 line:
get 5 right = 0.1
get 4 right = 0.12
get 3 right = 0.14
get 2 right = 0.16
get 1 right = 0.18
get 0 right = 0.2
normal palpebral fissue height
about 10mm
history
What brings you in today?
SYMPTOMS = LOFTSEA (Location, Onset, Frequency, Time, Self-treatment, Effect on patient, associations)
GH: Health conditions? Allergies? Medications? smoke?
POH: Previous issues with eyes? Prev attended HES? glasses or eye turn as a child or wear a patch?
FH: Health conditions? Eye conditions? Squint?
BH: Any birth abnormalities? Full-term normal delivery? birth weight?
what incom px present as
6th = eso worse in distance and side gaze
browns = hypo in PP, cant elevate eye
4th = up + in
3rd = down and out
What surgery test do you need to do?
Post op diplopia test (like PFR but keep going after they get double)
Two management options for consecutive exos
Botox and surgery
What does a microtropia mean for patching VA’s?
VAs will never be perfectly equal
What is Aniseikonia?
Difference in image sizes due to two very different RX in each eye e.g. RE -7.00 LE: +3.00
Anterior Pligiocephaly
Shorter orbit on affected side. This results in malpositioned trochlea. This gives rise to superior oblique under actions on ipsilateral side. In this case, it’s the corresponding over action of the L inferior oblique which is most obvious.
