Thursday, October 15, 2020

OPHTHALMOSCOPE

 Hi friends!!!


In our previous blogs, we have discussed about ISO 14971:2019 Risk Management for Medical Device. Please check out for the link below.


ISO 14971:2019 Risk Management for Medical Device


Risk Analysis, Risk Evaluation & Risk Control


Failure Mode Effect Analysis


In today's blog we are going to discuss about Ophthalmoscope.


The Ophthalmoscope is an important instrument used to examine the inside of the eye. Therefore it is important for every healthcare professionals to know about Ophthalmoscope.

 

Let's get into the topic. 


WHAT IS OPHTHALMOSCOPE?


The Ophthalmoscope is an instrument made up of light source and several small lens. The Ophthalmoscope is used to examine the inside of fundus of the eye and other internal structures. The ophthalmoscope is a coaxial optical system, which means the axis of illumination coincides with the axis of vision into the retina. The ophthalmoscope eliminates the shadows in order to facilitate the examination.


The procedure performed using Ophthalmoscope is called as ophthalmoscopy. The Ophthalmoscopy is also called as funduscopy. This procedure is used to check the condition of retina, optic nerve, vasculature, vitreous humor and other parts of the eye. The Ophthalmoscope produces images with approximately 15 times magnification.


The retina is the only portion of the central nervous system which is visible externally. Similarly, fundus is the only location where vasculature can be visualized.



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OPHTHALMOSCOPE SETTINGS


RED FREE

The red free option in ophthalmoscope is used to view vasculature closely.


BLUE

The blue option in ophthalmoscope is used to view corneal abrasions.


SLIT

The slit option in ophthalmoscope is used to view contour abnormalities of cornea, retina and lens.


GRID

The grid in ophthalmoscope is used to identify the distance between retinal lesions.


LARGE APERTURE

The larger aperture is used to examine dilated pupil after administering mydriatic drops.


MEDIUM APERTURE

The medium aperture is used for non-dilated pupil in a dark room setting.


SMALL APERTURE

The small aperture is used to view constricted pupil in a well-lit room setting.


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WHAT ARE THE TYPES OF

OPHTHALMOSCOPE?


There are two types of ophthalmoscope, they are as following.


DIRECT OPHTHALMOSCOPE

The direct ophthalmoscope is used to produce upright image (unreversed image) of the center of retina at about 15 times magnification. The direct ophthalmoscope is also called as traditional ophthalmoscope.


INDIRECT OPHTHALMOSCOPE

The indirect ophthalmoscope is used to produce the inverted image (reversed image) of the retina at about 2 to 5 times magnification. The indirect ophthalmoscope is also called as panoptic ophthalmoscope.


WHAT ARE THE FEATURES OF

OPHTHALMOSCOPE?


APERTURE DIAL

The aperture dial is used to modify the amount of light passing through the lens.


RHEOSTATIC SWITCH

The rheostatic switch is used to power the light source. It is used to adjust the brightness of the light.


FOCUSING WHEEL

The focusing wheel is used to make adjustment in the focus. The red option is for negative focus and green option is used for positive focus.


LENS SELECTION WHEEL

The ophthalmoscope has multiple lens. The lens selection wheel is used to select the lens desired for performing the procedure.


HOW TO FIND RETINA USING

OPHTHALMOSCOPE?


Direct the ophthalmoscope at 15 degrees from the center and look out for the red reflex. Keep following the red reflex until the retina is visible. While using direct ophthalmoscope, we should pivot the ophthalmoscope angling up, angling down, left and right. In case of indirect ophthalmoscope, we can pivot the ophthalmoscope or ask the patients to look up to view upper retina, look down to view lower retina and look at the light to visualize the macula.



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Now I hope you have acquired some knowledge about Ophthalmoscope.  We will discuss in detail about a topic related to Biomedical Engineering  in our future blogs.


NOTE: Dear friends!!!... Please do comment a topic related to Biomedical, so that we can discuss it in future blogs.


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