What should a normal optic disc look like? Typically the optic disc looks like an orange-pink donut with a pale centre. The orange-pink appearance represents healthy, well perfused neuro-retinal tissue. There are many pathological reasons
What should a normal optic disc look like?
Typically the optic disc looks like an orange-pink donut with a pale centre. The orange-pink appearance represents healthy, well perfused neuro-retinal tissue. There are many pathological reasons why a disc may lose this orange-pink colour and appear pale ie optic atrophy.
What color is a normal optic disc?
A normal optic disc is orange to pink in colour. A pale disc is an optic disc which varies in colour from a pale pink or orange colour to white. A pale disc is an indication of a disease condition.
What should the optic nerve look like?
A normal optic nerve head (ONH) usually is round or oval, mildly elevated and pink in color, with a centralized depression known as the cup. The horizontal diameter of a typical optic nerve is approximately 1.5mm.
How do you assess optic discs?
Probably the most accurate way to manually measure the optic disc is to do high-plus non-contact funduscopy using a 78- or 90-D lens and a slit lamp. To do this, simply bring the disc into view with your high plus lens using a narrow slit lamp beam.
How do you evaluate the suspicious optic disc?
When estimating horizontal and vertical C/D ratios, the clinician should view the optic disc and its vessels stereoscopically to assess the extent of the internal rim border. The clinician should also look for disc rim sloping or saucerization, which may be an early, subtle sign of damage.
How do you describe an optic disc?
The optic nerve head or optic disc describes the area of the optic nerve that is visible clinically on examination. Over a million nerve fibres pass through the lamina cribrosa and are bundled together through the optic nerve towards the brain.
What should the optic disc look like in an adult?
Normal fundus – adult. The optic disc appears pink with sharp margins and a cup-to-disc ratio of approximately 0.35. The vasculature is normal in course and caliber. The striated sheen radiating outward from the disc is evidence of a healthy retinal nerve fiber layer. There are no lesions, scars, or pigmentary changes in the macula or periphery.
How to know if your optic disc is glaucomatous?
1 A C/D ratio less than 0.4 usually denotes a non-glaucomatous nerve unless the patient has an abnormally small optic… 2 A C/D ratio between 0.4 and 0.8 can characterize a patient with a normal optic disc (i.e., physiologic cupping),… 3 If the C/D ratio is 0.8 or greater, consider the individual’s disc as glaucomatous unless proven otherwise.
Where is the thickest part of the optic disc?
STEP ONE: THE OPTIC NERVE EXAM. In a normal optic disc, the thickest portion of the neuroretinal rim is located inferiorly at 6 o’clock, followed next by the superior, nasal and temporal portions of the rim. The glaucomatous eye may violate the ISNT rule. Thinning will occur at the inferior neuroretinal rim.
What causes the pallor of the optic disc?
The relative pallor of the optic disc is caused by the reflection of light from the myelin sheaths of the optic nerve. In the center of the normal optic disc, there is a funnel-shaped depression known as physiologic cupping. The cup is the portion of the disc that is central, lighter in color, and penetrated by the retinal vessels.