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Medical Device and Medical Diagnosis:
Ophthalmoscope and Retinopathy.
The prototype for the modern ophthalmoscope was invented by Charles
Babbage in 1847. The modern ophthalmoscope was designed by
Hermann von Helmholtz in 1851. The name for ophthalmoscope was
put into common use in 1854.
An ophthalmoscope is used to view the fundus, or the posterior part of
the eye. Its clinical applications are for pre-screening patients with
macular degeneration, glaucoma, and retinal detachments. By first locating the optic disc through the ophthalmoscope, you can examine the
retinal arteries and veins coming out the optical disc. The next time you
and a fellow BMET are inspecting the ophthalmoscope, look for the optic disc on the medial side of the fundus.
http://www.college-optometrists.org/
en/knowledge-centre/museyeum/
online_exhibitions/
optical_instruments/
ophthalmoscopes/
ophthalmoscopes2.cfm
In this article, the reader will:
Learn the parts of the Ophthalmoscope.
Learn the major parts of the retina.
Learn indicators of hypertensive retinopathy
Learn indicators of Macular Degeneration
Learn indicators of diabetic Retinopathy
Anatomy of the Ophthalmoscope:
Head:
The head is made up of several components. The diopter disc is what
controls the aperture sight. For you gun enthusiasts, this is what allows
you to aim the device. Moving the diopter disc changes the lenses while
the reading window shows which lens number is currently in front of the
reflecting mirror. If you turn the diopter disc clockwise, you will see the
lens number show negative numbers, -1, -2, -3, -4, -5, -6, -8, -10, -16, 20, -25, -35D. If your Ophthalmoscope does not show negative numbers, it will show absolute value of the numbers, but with a color red.
The negative numbers represent the focal point of concave lenses. If
you move the diopter disc counter-clockwise, you will see the lenses
number move into positive numbers, +1, +2, +3, +4,+5, +6, +8, +10,
+12, +16, +20D. Again, positive numbers will be represented in green
on some ophthalmoscopes. The positive numbers indicate convex
lenses are in front of the mirror.