The importance of describing visual disorders
The Stargardt disease is diagnosed following the description of visual disorders and according to the age of the person. This macular dystrophy is in most cases an early diagnosis due to the resulting visual disorders: difficulty to read, colour vision impairment, photophobia.
Specific tests and further evaluations will confirm the diagnosis:
Funduscopy
This examination studies the retina. It reveals an impairment of the macula with white or yellowish stains on its border caused by accumulation of a toxic matter called lipofuscin (matter caused by the deterioration of organelle cells which, when building up, prevents the efficiency of various cells) in the cells of the retinal pigment epithelium. The optic nerve area and the eye vessels are normal.
Angiography with fluorescein
The angiography shows the impairment of the centre of the retina, the white fluorescent stains and a « choroidian silence » which corresponds to a delay in the spreading of the fluorescein in the choroid (area of the eye vessels). Another similar test is the autofluorescence of the back of the eye.
Colour vision test
At first, red and green colours are not easily distinguished. Later on, other colours may be impaired.
Electroretinogram
This examination evaluates the electrical activity of the retina and is generally normal. Results may differ with peripheral retinal damage.
Histologic examination
An accumulation of lipofuscin in the retinal pigmented epithelium is observed.