VF v3

Question 1

which px require VF assessment?

Answer 1

-FH of glaucoma
- if px reports field loss
- recent onset HA
-assesing progression/severity ogf condition e.g glaucoma
-localisation e.g patient has a strike and you find neurological defect corresponding to certain portion of visual pathway

• acquired colour vision changes/anything neurological
  -certain medications- quine
  dvll

Question 2

what is supra threshold

Answer 2

-quick
- at start of test px threshold estimated ( either by thresholding a few central locations/using px agess0
and all test stimuli are presented brighter than this level

4,5 or 6 dB

Question 3

what are full thresholds

Answer 3

• longer
• test estimates the threshold at a variety of points within the VF

frequently presented stimuli that are around threshold brightness

supra threshold stimulus is presented at each location based on values from prior points.Intensity is decreased at fixed increments until the stimulus is no longer seen, then increased at forced increments till it is seen again (like a stair case)

• threshold value is taken to be equal to th intensity of the last stimulus seen at the location

Question 4

how might medication cause VF defect

Answer 4

1) chloroquine- central/ring cotoma
2) alcohol vit defienciency- bilateral central , paracntral or centrocecak defect

3_ vaigbatrin - concentric constriction with binasal predominance

Question 5

retinal lesion

Answer 5

RP- ring of scotoma
artery or vein occlusion
RD - focal defect in affected area

Question 6

ON

Answer 6

glaucoma- arcuate,nasalstep, paracentral
coloboma
optic disc drusen - arcuate , enlargement of blind spot
papilloedem
ON - altitudinal ,central ,peripheral
ischemic optic neuropathy - respect H midline

Question 7

in the average person what is the extent of VF

Answer 7

superior 60
inferior 70
temporally 100