What is the use of ophthalmoscope?

What is the use of ophthalmoscope?

It is used to detect and evaluate symptoms of retinal detachment or eye diseases such as glaucoma. Ophthalmoscopy may also be done if you have signs or symptoms of high blood pressure, diabetes, or other diseases that affect the blood vessels.

What are the parts of the ophthalmoscope?

The ophthalmoscope consists of a head and a handle (Figures 4-8 and 4-9). The head contains viewing lenses and beam selection controls. The viewing lens control (lens wheel) is used to focus the instrument.

What is the principle of ophthalmoscope?

In summary, the purpose of the ophthalmoscopy lens in indirect ophthalmoscopy is to redirect diverging pencils of light emerging from the patient’s pupil toward the observer’s eye. In doing so, the lens also focuses parallel rays within each pencil into an inverted aerial image of the patient’s fundus.

Which lens is used in ophthalmoscope?

The viewing system of the instrument (Figure 2) consists of a pair of low-powered convex lenses. This design affords the examiner a stereoscopic view of the virtual image. The +20D lens is the standard lens for general examination offering 3x magnification and a field of view of approximately 45°.

How many types of ophthalmoscopy are there?

two
It is of two major types: Direct ophthalmoscopy one that produces an upright, or unreversed, image of approximately 15 times magnification. Indirect ophthalmoscopy one that produces an inverted, or reversed, image of 2 to 5 times magnification.

What are the two types of ophthalmoscope?

There are two main types of ophthalmoscopes: direct and indirect. Direct ophthalmoscopes are simple hand-held ophthalmic instruments consisting of a concave mirror, a light source, an eye piece for the ophthalmic professional conducting the examination, and a simple handle.

Which mirror is used in ophthalmoscope?

Concave Mirror
Concave Mirror Uses in the Ophthalmoscope Concave mirrors are used in optical instruments such as Ophthalmoscope. Ophthalmoscope consists of a concave mirror with a hole in the centre.

When performing the Ophthalmoscopic examination which finding of the optic discs is abnormal?

No wrinkling of the retina should be seen. Chalky whiteness or erythema of the disk is abnormal, as are indistinct disk margins. Any sharp change in elevation that renders one area out of focus with the ophthalmoscope, while the remainder of the retina remains in focus, is abnormal.

Is ophthalmoscope concave mirror?

Concave mirrors are used in optical instruments such as Ophthalmoscope. Ophthalmoscope consists of a concave mirror with a hole in the centre. The doctor focuses through the small hole from behind the concave mirror while a light beam is directed into the pupil of the patient’s eye.

Is ophthalmoscope a refraction or reflection?

The view provided by the ophthalmoscope is monocular, non-stereoscopic (2D), narrow field (5°), and is magnified about 15 times. Light from a bulb (Figure 2) is reflected at right angles and projected as a spot through the iris of the patient to illuminate the retina.

What is normal optic disc cupping?

The normal cup-to-disc ratio is less than 0.5. A large cup-to-disc ratio may imply glaucoma or other pathology. However, cupping by itself is not indicative of glaucoma. Rather, it is an increase in cupping as the patient ages that is an indicator for glaucoma.

Which type of mirror is used in ophthalmoscope?

Concave mirrors
Concave mirrors are used in optical instruments such as Ophthalmoscope. Ophthalmoscope consists of a concave mirror with a hole in the centre. The doctor focuses through the small hole from behind the concave mirror while a light beam is directed into the pupil of the patient’s eye.