What is the Amsler chart used for? Describe it.
to assess the impact of a disease on pxs macula func
qualitative, not quantitative test
a grid, 10’ either side of fixation
7 charts with varying patterns
When is Amsler chart used?
unexplained reduced VA
symptoms of distortion + scotoma
signs of AMD
px on certain meds: chloroquine or tamoxifen
Which Amsler chart is this? What is it used for?
Chart 1
detect scotoma and metamorphopsia
Which chart is this? What is it used for?
Chart 2
diagonal lines to detect centra scotoma and ask px to fixate where lines wold cross
What chart is this? What is it used for?
Chart 3= red on black version of chart 1
to enhance detection of certain pathologies
What is this chart? What is it used for?
Chart 4
to differientiate between metamorphopsia and scotoma
(met wont show bz pattern is random. scotoma wil show)
Which Amsler chart is this? what is it used for?
Chart 5
reveals which meridian metamorphopsia is
Which amsler chart is this? what is it used for?
Chart 6
similar to chart 5 but reversed contrast
closer spacing to detect subtle chnages at fovea
Which amsler chart is this. What is it used for?
chart 7
detect subtle defects at fovea
how to test px with Amsler Chart
explain test to px
px to wear near Rx - avoid PPLs
occlude on eye - ALWAYS TEST MONOCULARLY
hold chart at 28-30cm (measure this)
ask px to look at central dot + ask:
can you see all 4 corners of outer square?
are the lines straight or wavy - test distortion
are they any areas of the grid which are missing- test scotoma
How to record results?
ask px to draw what they see
** white-on-black = test charts
**black-on-white=record charts
positive scotoma= big black spot. seen with WET AMD bz bld vessels have haemorrhaged and scar tissue formed.
negative scotoma= empty space, no grid. seen with DRY AMD bz atrophy
Last changed8 days ago
