What is the function of the macula lutea?
The macula lutea is an oval-shaped, pigmented, light-sensitive area near the center of the retina in the posterior pole of the eyeball. It is one of the most important parts of the eye that is responsible for our central vision or visual acuity and color perception.
How do you inspect the macula in cataract?
6. Finally, inspect the macula by asking the patient to briefly look directly into the light of the ophthalmoscope. The macula is found lateral (temporal) to the optic nerve head and is yellow in colour.
What is an ophthalmoscope used for?
The ophthalmoscope (also known as a fundoscope) is a tool used in medicine to examine the interior of the eye including the retina, fovea, choroid, macula, optic disc and blood vessels.
Why is my macula lutea yellow in color?
Also, when viewed or photographed by your eye doctor, the macula lutea has a yellowish appearance (in contrast to the rest of the retina, which is red). The yellow color is due to the macular pigment, which is composed mainly of lutein and zeaxanthin from your diet.
What can you see with ophthalmoscope?
Ophthalmoscopy (also called fundoscopy) is an exam your doctor, optometrist, or ophthalmologist uses to look into the back of your eye. With it, they can see the retina (which senses light and images), the optic disk (where the optic nerve takes the information to the brain), and blood vessels.
How do you examine macula?
To look at the macula, ask the patient to look directly into the ophthalmoscope light. The ophthalmoscope can also be used for examining the anterior part of the eye by turning the lens dial to ∼ +10.
Which retinal structures can be viewed through the ophthalmoscope?
The retinal structures viewed through the ophthalmoscope are the optic disc, the retinal vessels, the general background, and the macula.
Is macula lutea blind spot?
The spot at the back of the eye, from where optic nerve fibres leave is free from rods and cones. This spot is devoid of the ability for vision and is called blind spot. Yellow spot or area centralis or Macula lutea is in the exact centre of the retina. 1.
Which structures are examined with an ophthalmoscope?
Rationale: The ophthalmoscope illuminates the internal eye structures. Its system of lenses and mirrors enables you to look through the pupil at the fundus (background) of the eye, much like looking through a keyhole at a room beyond. An otoscope is used to examine the ear canal and tympanic membrane.
When would you use the ophthalmoscope?
When using the ophthalmoscope, you would: A. Remove your own glasses and approach the patient's left eye with your left eye. A patient is known to be blind in the left eye.
Which lens is used in direct ophthalmoscope?
A 20D lens is then placed 3 to 5 cm in front of the patient's eye in the path of the ophthalmoscope light beam, the examiner then needs to move slightly toward or away from the patient until a clear image of the retina is observed.
What is the difference between ophthalmoscope and otoscope?
An Otoscope is used to examine the ears, while an ophthalmoscope is used to examine the eyes.
Does ophthalmoscope reflect or refract?
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 unique about the macula lutea?
It is the part of the retina that is responsible for sharp, detailed central vision (also called visual acuity). The macula lutea, also called fovea, contains a very high concentration of cones. These are the light-sensitive cells in the retina that give detailed central vision.
What is the difference between macula lutea and fovea centralis?
The macula lutea is a yellow spot in the retina that allows light to focus when looking at an object. The fovea centralis is an anatomical structure in the center of the macula lutea that contains a high density of cone photoreceptors and allows the light to focus within the eye.
How do you test the blind spot in your eye?
How do you test for blind spots? Close your left eye and stare at the cross mark on the other side of this page with your right eye. Off to the right you should be able to see the spot. Don't look directly at it; just notice that it is there, off to the right.
What are the early warning signs of macular degeneration?
SymptomsVisual distortions, such as straight lines seeming bent.Reduced central vision in one or both eyes.The need for brighter light when reading or doing close-up work.Increased difficulty adapting to low light levels, such as when entering a dimly lit restaurant.Increased blurriness of printed words.More items...•
What is the difference between macula and macular?
The macula is a place. It is the functional center of the retina. The term macular is an adjective. “Macular” is not a disease.
What is difference between macula and retina?
The retina is a layer of tissue in the back of your eye that senses light and sends images to your brain. In the center of this nerve tissue is the macula. It provides the sharp, central vision needed for reading, driving and seeing fine detail.
What happens if macula is damaged?
If the damage is near the macula, one could notice various visual effects such as general poor vision, distortion of images such as straight lines appearing wavy, blurry spots in one's central vision, and/or vision with images appearing and disappearing.
How to brighten an ophthalmoscope?
The first one is light or brightness. So for the brightness all you need to do is press the little button and twist it and the more you twist it the brighter the light will become. There's two things to remember when dealing with brightness.
Where is the vasculature visualized?
Likewise the fundus is the only location where vasculature can be visualized. So much of what we see in internal medicine is vascular related and so viewing the fundus is a great way to get a sense for the patient’s overall vasculature.
How far away should I set my 20/20 vision?
So before we start the demonstration I need to make sure that this setting is adjusted for my vision. So I look at something about 10 to 15 feet away and make sure it's in focus. After that it's very unlikely I need to touch this setting again. Unless the patient's extremely nearsighted or farsighted you usually can set it for yourself and not have to worry about it again. If you have 20/20 vision or you have contacts in that lead you to have 20/20 vision you actually don't have to do anything other than leave it right at the zero.
What type of equipment do eye specialists use?
Before we can do anything else we have to talk about the equipment. Usually we use direct ophthalmoscopes. Indirect ophthalmoscopes are the type of gear that the eye specialists wear on their head. These direct ophthalmoscopes come in a couple different forms and twoof the most common ones I'm holding in my hands.
Which is the best place to visualize?
The optic disc is the best place to visualize because number one, it can be associated with a lot of pathology, a lot of medical pathology. And number two, there's no rods or cones there so it's going to cause the least amount of pain and least amount of pupil constriction.
How to check if an ophthalmoscope is working?
Determine if the ophthalmoscope is working properly. Turn the power switch to the on position to check if the light works. If not, replace the batteries and try again. Look through the aperture (eyepiece) to ensure clarity. Remove or slide open the aperture's cover if one exists.
Where is the macula located?
The macula appears as a darker disc approximately in the center of the retina , with the fovea a bright point in the middle of the macula. Assess the other eye. Repeat the procedure on the other eye, and remember to switch which hand and eye you use for examination.
What to do when you are dilating your pupil with mydriatic drops?
If you will be dilating the pupil with mydriatic drops, explain the procedure and effects, including that they should have someone drive them home after. You don’t have to go into much detail about the eye exam.
How to make your ophthalmoscope magnification sharper?
Darken the room. Dim the lights considerably. Having extra lights on hinders the sharpness of the ophthalmoscope magnification. [11]
What light source is used for eye exam?
There are several aperture and filter options that can be used for specific goals in an eye examination. The most common setting used is the Medium light source, because most exams are done in a darkened room when the patient has not been treated with mydriatic (dilating) eye drops. Ophthalmoscopes may differ in which settings are available, but some possibilities are:
How to focus ophthalmoscope?
Focus the instrument using the focusing wheel. Generally, you should focus your ophthalmoscope to the “0” setting, which is the baseline. Be aware that focusing towards the positive numbers – sometimes marked on the instrument in green – focuses on things closer to you, and focusing towards the negative numbers – sometimes in red – focuses on things farther from you.
What is the purpose of an ophthalmoscope?
The ophthalmoscope (also known as a fundoscope) is a tool used in medicine to examine the interior of the eye including the retina, fovea, choroid, macula, optic disc and blood vessels. Optometrists and general practitioners alike can use an ophthalmoscope to diagnose or monitor diseases of the eye as well as conditions like hypertension ...
What is the hole in the centre of the iris that allows light to enter the eye and reach the retina?
The pupil is the hole in the centre of the iris that allows light to enter the eye and reach the retina.
Which way should you assess each quadrant of the retina and the associated vascular arcades?
5. Methodically assess each quadrant of the retina and the associated vascular arcades in a clockwise or anticlockwise fashion looking for evidence of pathology:
How many flashcards are there in OSCE?
You might also be interested in our OSCE Flashcard Collection which contains over 2000 flashcards that cover clinical examination, procedures, communication skills and data interpretation.
Why is pupillary color asymmetric?
Asymmetry in pupillary colour is most commonly due to congenital disease.
Why is the pupil size larger in bright light?
If the difference in pupil size becomes greater in bright light such as when facing a window in daylight, this would suggest that the larger pupil is the pathological one. This is because the normal pupil will constrict in brighter light accentuating the difference in size. If the difference is more pronounced in dim lighting, this would imply the smaller pupil is abnormal as the larger pupil would then dilate while the pathologically small pupil remains the same size.
What is the name of the condition where the eyelid is down and out?
Prominence of the eyes. Abnormal eyelid position: ptosis can be a sign of Horner’s syndrome (often very subtle ptosis with miosis) and oculomotor nerve palsy (can vary from partial to complete ptosis and usually with a ‘down and out’ eye position and an enlarged pupil) Abnormal pupillary shape, size and/or asymmetry.