Table of Contents
What instrument is used to view eyes?
Ophthalmoscope. An ophthalmoscope is a tool that the ophthalmologist uses to examine the interior of the eye.
What instruments see retina?
Retinoscope: A retinoscope is a handheld device used to determine the refractive power of the eye by observing the lights and shadows on the pupil when a mirror illumines the retina. It is also useful for determining how well the eyes work together, accommodate, to see clearly.
What is the optic disc called?
the optic nerve head
The optic disc, also known as the optic nerve head, forms a slightly raised spot on the nasal side of the retina. Here, there are no photoreceptors, hence it is known as the blind spot of the eye. The optic disc has a slight cup-shaped depression, called the physiologic cup.
What are the types of ophthalmoscope?
There are different types of ophthalmoscopy.
- Direct ophthalmoscopy. You will be seated in a darkened room.
- Indirect ophthalmoscopy. You will either lie or sit in a semi-reclined position.
- Slit-lamp ophthalmoscopy. You will sit in a chair with the instrument placed in front of you.
What are rods cones?
The human retina has two types of photoreceptors to gather light namely rods and cones. While rods are responsible for vision at low light levels, cones are responsible for vision at higher light levels. The light levels where both are functional are known as mesopic.
What is cupping in eye?
The optic nerve sits in the back of your eye, and it’s surrounded by a dense network of other nerve fibers. When those smaller nerves die, the space they leave behind looks a bit like a cup. Doctors call this “optic nerve cupping.” Cupping can be a sign of glaucoma, and this condition always needs treatment.
What are the parts of 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.
Is cupping good for eyes?
Facial Cupping improves the blood flow from under your eyes, which helps in the formation of new connective tissues. It also provides vitality to your skin by promoting collagen production and reduces puffiness under your eyes.
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.
What is rods in eyes?
Rods are a type of photoreceptor cell in the retina. They are sensitive to light levels and help give us good vision in low light. They are concentrated in the outer areas of the retina and give us peripheral vision. Rods are 500 to 1,000 times more sensitive to light than cones.
What are S cones?
The S cone is highly conserved across mammalian species, sampling the retinal image with less spatial frequency than other cone photoreceptors. In human and monkey retina, the S cone represents typically 5–10% of the cone mosaic and distributes in a quasi-regular fashion over most of the retina.
What is cone and rod?