2. Amsler Grid
Used since : 1945 AD
Developed by :Marc Amsler, swiss ophthalmologist.
Looks like a graph paper with multiple small sized
boxes on it having a centre dark spot.
3. Amsler Grid
•The grid chart evaluate the
central 20 degree of the visual
field.
•It is a diagnostic tool that is
used mainly in screening,
detection and monitoring
macular diseases
(e.g. Macular degenerations,
epiretinal membranes)
as well as the optic nerve and
the visual pathway.
4.
5. Availability
Original Amsler’s grid was black and white.
Available in
Black on white
White on black.
A colour version with a blue and yellow grid is more
sensitive and can be used to test for a wide variety of
visual pathway abnormalities, associated with retina,
the optic nerve & pituitary gland.
6. Procedure
The patient is made to wear his reading glasses if any,
holds the chart at 16 inches(40cm) away infront of the
eye.
Patient looks with each eye separately by covering one
eye.
He is asked to focus at the small dot in the centre of the
grid.
While he is looking at the dot, ask him to report if any
line on the grid is
(distorted, broken, blurred area, missing area, dark area,
corners, sides).
Mark the area of abnormality, if any on the chart and
refer to the ophthalmologist.
7. There are seven
charts, each consisting
of a 10cm square.
It is most commonly
used. It comprises a
high contrast white
grid on a black
background. The
outer grid encloses
400 smaller 5mm
squares. When viewed
about one-third of a
meter, each small
square subtends an
angle of a 1 degree.
8. Is a similar to chart 1
but has diagonal
lines that aid
fixation in patients
unable to see the
central spot as a
result of a central
scotoma
9. Is to identical to chart
1 but has red squares.
The red on black
design aim to
stimulate long
wavelength foveal
cones. It is used to
detect colour
scotomas and
desaturation that may
occur in toxic
maculopathies , optic
neuropathies and
chiasmal lesions.
10. Consisting only of
random dots is used
mainly to
distinguish scotoma
from
metamorphosia, as
there is no form to
be distorted.
11. Consisting of
horizontal lines and
is designed to detect
metamorphosia
along specific
meridian. It is of
particular value in
the evaluation of
patients with
reading difficulties.
12. It a similar to chart 5
but has a white
background and the
central lines are
closer together
enabling more
detailed evaluation.
13. Exhibits a fine
central grid , each
square subtending
an angle of a degree
and is therefore
more sensitive.
