Ophthalmoscope

Ophthalmoscope

The ophthalmoscope (or funduscope) is an instrument used to examine the eye. Its use is crucial in determining the health of the retina and the vitreous humor.

In patients with headaches, the finding of swollen optic discs, or papilledema, on ophthalmoscopy is a key sign, as this indicates raised intracranial pressure (ICP) which could be due to hydrocephalus, benign intracranial hypertension (aka pseudotumor cerebri) or brain tumor, amongst other conditions. Cupped optic discs are seen in glaucoma.

In patients with diabetes mellitus, regular ophthalmoscopic eye examinations (once every 6 months to 1 year) is mandatory to screen for diabetic retinopathy as visual loss due to diabetes can be prevented by retinal laser treatment if retinopathy is spotted early.

In arterial hypertension, hypertensive changes of the retina closely mimic those in the brain, and may predict cerebrovascular accidents (strokes).

Numerous companies manufacture direct ophthalmoscopes, including Welch Allyn, Heine, Riester and Keeler. Ophthalmoscopes are often sold with otoscopes as a diagnostic set.

History

Although originally invented by Charles Babbage in 1847, it was not until it was independently reinvented by Hermann von Helmholtz in 1851 that its usefulness was recognized.

While training in France, Andreas Anagnostakis, MD, an ophthalmologist from Greece, came up with the idea of making the instrument hand-held by adding a concave mirror. Liebreich created a model for Anagnostakis, which he used in his practice and subsequently when presented at the first Ophthalmological Conference in Brussels in 1857, the instrument became very popular among ophthalmologists.

In 1915, Willam Noah Allyn and Frederick Welch invented the world's first hand-held direct illuminating ophthalmoscope [ [http://www.hoovers.com/welch-allyn,-inc./--ID__54678--/free-co-factsheet.xhtml Hoovers Citation] ] , precursor to the device now used by clinicians around the world. This refinement and updating of von Helmholtz's invention enabled ophthalmoscopy to become one of the most ubiquitous medical screening techniques in the world today. The company started as a result of this invention is Welch Allyn.

Types

There are two major types of ophtalmoscopes, direct and indirect.

Direct ophthalmoscope

It is an instrument about the size of a small flashlight (torch) with several lenses that can magnify up to about 15 times. This type of ophthalmoscope is most commonly used during a routine physical examination [http://www.healthbanks.com/PatientPortal/Public/LinkPublic.do?ArticleID=HW5hw5223 healthbanks.com] ]

Indirect ophthalmoscope

An indirect ophthalmoscope constitutes a light attached to a headband, in addition to a small handheld lens. It provides a wider view of the inside of the eye. Furthermore, it allows a better view of the fundus of the eye, even if the lens is clouded by cataracts .

An indirect ophthalmoscope can be either monocular or binocular.

ee also

*Charles Schepens
*Retinoscope
*Scanning laser ophthalmoscopy

References

External links

* [http://careerfocus.bmjjournals.com/cgi/content/full/329/7461/56 Overview at bmjjournals.com]
* [http://www.sciencedaily.com/releases/2007/03/070305140957.htm A new digital hand held ophthalmoscope] - sciencedaily.com -
* [http://www.nlm.nih.gov/medlineplus/ency/article/003881.htm Medlineplus] about different types of ophtalmoscopy


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Look at other dictionaries:

  • Ophthalmoscope — Oph*thal mo*scope, n. [From Gr. ofqalmo s the eye + scope.] (Physiol.) An instrument for viewing the interior of the eye, particularly the retina. Light is thrown into the eye by a mirror (usually concave) and the interior is then examined with… …   The Collaborative International Dictionary of English

  • ophthalmoscope — (n.) 1857 in English; coined 1852 by German physician and physicist Hermann Ludwig Ferdinand von Helmholtz (1821–1894) from OPHTHALMO (Cf. ophthalmo ) + SCOPE (Cf. scope) …   Etymology dictionary

  • ophthalmoscope — [äf thal′mə skōp΄] n. [ OPHTHALMO + SCOPE] an instrument used to examine the interior of the eye: it consists of a perforated mirror arranged to reflect light from a small bulb into the eye ophthalmoscopic [äf thal′məskäp′ik] adj. ophthalmoscopy… …   English World dictionary

  • ophthalmoscope — ophthalmoscopic /of thal meuh skop ik, op /, ophthalmoscopical, adj. /of thal meuh skohp , op /, n. an instrument for viewing the interior of the eye or examining the retina. [1855 60; OPHTHALMO + SCOPE] * * * ▪ instrument       instrument for… …   Universalium

  • ophthalmoscope — A device for studying the interior of the eyeball through the pupil. SYN: funduscope. [ophthalmo + G. skopeo, to examine] binocular o. an o. that provides a stereoscopic view of the fundus. demonstration o. an o. by which the fundus may be seen… …   Medical dictionary

  • ophthalmoscope — n. an instrument for examining the interior of the eye. There are two types. The direct ophthalmoscope enables a fine beam of light to be directed into the eye and at the same time allows the examiner to see the spot where the beam falls inside… …   The new mediacal dictionary

  • ophthalmoscope — noun Etymology: International Scientific Vocabulary Date: circa 1857 an instrument for use in viewing the interior of the eye and especially the retina • ophthalmoscopic adjective • ophthalmoscopy noun …   New Collegiate Dictionary

  • ophthalmoscope — noun an instrument for examining the interior of the eye …   Wiktionary

  • ophthalmoscope — (o ftal mo sko p ) s. m. Instrument qui sert à examiner l intérieur de l oeil. ÉTYMOLOGIE    Termes grecs signifiant oeil et examiner …   Dictionnaire de la Langue Française d'Émile Littré

  • ophthalmoscope — instrument for viewing the interior of the eye Scientific Instruments …   Phrontistery dictionary

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