Amsler grid

Post on 28-Nov-2014

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Transcript of Amsler grid

Suhail Wahab Khalil

BSVS 4th Year,

Isra School Of Optometry.

Amsler GridUsed 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.

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.

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.

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.

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.

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

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.

Consisting only of random dots is used mainly to distinguish scotoma from metamorphosia, as there is no form to be distorted.

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.

It a similar to chart 5 but has a white background and the central lines are closer together enabling more detailed evaluation.

Exhibits a fine central grid , each square subtending an angle of a degree and is therefore more sensitive.

MACULAR EDEMA

TUMOR

METAMORPHOSIA

SCOTOMA

GLAUCOMA

PERIPHERAL FIELD LOSS

Thank You(for Bearing with Me)

still any Question ???