Ophthalmoscopy, also called funduscopy, is a test that allows a health professional to see inside the
fundus of the eye and other structures using an ophthalmoscope (or funduscope). It is done as part of an
eye examination
An eye examination is a series of tests performed to assess vision and ability to focus on and discern objects. It also includes other tests and examinations pertaining to the eyes. Eye examinations are primarily performed by an optometrist, op ...
and may be done as part of a routine
physical examination
In a physical examination, medical examination, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally consists of a series of questions about the patien ...
. It is crucial in determining the health of the
retina
The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then ...
,
optic disc
The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye.
The ganglion cell axons form the ...
, and
vitreous humor
The vitreous body (''vitreous'' meaning "glass-like"; , ) is the clear gel that fills the space between the lens and the retina of the eyeball (the vitreous chamber) in humans and other vertebrates. It is often referred to as the vitreous humor ...
.
The
pupil
The pupil is a black hole located in the center of the iris of the eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. It appears black ...
is a hole through which the eye's interior will be viewed. Opening the pupil wider (dilating it) is a simple and effective way to better see the structures behind it. Therefore, dilation of the pupil (
mydriasis
Mydriasis is the dilation of the pupil, usually having a non-physiological cause, or sometimes a physiological pupillary response. Non-physiological causes of mydriasis include disease, trauma, or the use of certain types of drugs.
Normally, as ...
) is often accomplished with medicated
eye drop
Eye drops or eyedrops are liquid drops applied directly to the surface of the eye usually in small amounts such as a single drop or a few drops. Eye drops usually contain saline to match the salinity of the eye. Drops containing only saline ...
s before funduscopy. However, although
dilated fundus examination
Dilated fundus examination or dilated-pupil fundus examination (DFE) is a diagnostic procedure that employs the use of mydriatic eye drops (such as tropicamide) to dilate or enlarge the pupil in order to obtain a better view of the fundus of the ...
is ideal, undilated examination is more convenient and is also helpful (albeit not as comprehensive), and it is the most common type in
primary care
Primary care is the day-to-day healthcare given by a health care provider. Typically this provider acts as the first contact and principal point of continuing care for patients within a healthcare system, and coordinates other specialist care t ...
.
An alternative or complement to ophthalmoscopy is to perform a
fundus photography
Fundus photography involves photographing the rear of an eye, also known as the fundus. Specialized fundus cameras consisting of an intricate microscope attached to a flash enabled camera are used in fundus photography. The main structures that ...
, where the image can be analysed later by a professional.
Types
It is of two major types:
* Direct ophthalmoscopy one that produces an upright, or unreversed, image of approximately 15 times magnification.
* Indirect ophthalmoscopy one that produces an inverted, or reversed, image of 2 to 5 times magnification.
Each type of ophthalmoscopy has a special type of ophthalmoscope:
* The ''direct ophthalmoscope'' 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. The pan-ophthalmoscope has a larger primary lens with a variable focusing, allowing for a wider field-of-view.
* An ''indirect ophthalmoscope'', on the other hand, 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
cataract
A cataract is a cloudy area in the lens of the eye that leads to a decrease in vision. Cataracts often develop slowly and can affect one or both eyes. Symptoms may include faded colors, blurry or double vision, halos around light, trouble w ...
s.
[ An indirect ophthalmoscope can be either monocular or binocular. It is used for peripheral viewing of the retina.
]
Medical uses
Ophthalmoscopy is done as part of a routine physical or complete eye examination, mainly done by optometrists
Optometry is a specialized health care profession that involves examining the eyes and related structures for defects or abnormalities. Optometrists are health care professionals who typically provide comprehensive primary eye care.
In the Uni ...
and ophthalmologists
Ophthalmology ( ) is a surgical subspecialty within medicine that deals with the diagnosis and treatment of eye disorders.
An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Following a medic ...
. It is used to detect and evaluate symptoms of various retinal vascular diseases
Retinal (also known as retinaldehyde) is a polyene chromophore. Retinal, bound to proteins called opsins, is the chemical basis of visual phototransduction, the light-detection stage of visual perception (vision).
Some microorganisms use retin ...
or eye diseases such as glaucoma
Glaucoma is a group of eye diseases that result in damage to the optic nerve (or retina) and cause vision loss. The most common type is open-angle (wide angle, chronic simple) glaucoma, in which the drainage angle for fluid within the eye rem ...
. In patients with headache
Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches.
Headaches can occur as a result ...
s, the finding of swollen optic disc
The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. Because there are no rods or cones overlying the optic disc, it corresponds to a small blind spot in each eye.
The ganglion cell axons form the ...
s, or papilledema
Papilledema or papilloedema is optic disc swelling that is caused by increased intracranial pressure due to any cause. The swelling is usually bilateral and can occur over a period of hours to weeks. Unilateral presentation is extremely rare.
In ...
, on ophthalmoscopy is a key sign, as this indicates raised intracranial pressure
Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and at rest, is normally 7–15 Millimeter of mercury, mmHg ...
(which could be due to hydrocephalus
Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased intracranial pressure, pressure inside the skull. Older people may have headaches, double vision, poor ...
, benign intracranial hypertension (aka pseudotumor cerebri) or brain tumor
A brain tumor occurs when abnormal cells form within the brain. There are two main types of tumors: malignant tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and seconda ...
, amongst other conditions. Cupped optic discs are seen in glaucoma. In patients with diabetes mellitus
Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ap ...
, regular ophthalmoscopic eye examinations (once every 6 months to 1 year) are important to screen for diabetic retinopathy
Diabetic retinopathy (also known as diabetic eye disease), is a medical condition in which damage occurs to the retina due to diabetes mellitus. It is a leading cause of blindness in developed countries.
Diabetic retinopathy affects up to 80 perc ...
as visual loss due to diabetes can be prevented by retinal laser treatment if retinopathy is spotted early. In arterial hypertension
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...
, hypertensive changes of the retina closely mimic those in the brain and may predict cerebrovascular accident
A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...
s (strokes).
Dilation of the pupil
To allow for better inspection through the pupil
The pupil is a black hole located in the center of the iris of the eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. It appears black ...
, which constricts because of light from the ophthalmoscope, it is often desirable to dilate
Dilation (or dilatation) may refer to:
Physiology or medicine
* Cervical dilation, the widening of the cervix in childbirth, miscarriage etc.
* Coronary dilation, or coronary reflex
* Dilation and curettage, the opening of the cervix and surgic ...
the pupil by application of a mydriatic agent
Mydriasis is the Pupillary dilation, dilation of the pupil, usually having a non-physiological cause, or sometimes a physiological pupillary response. Non-physiological causes of mydriasis include disease, Physical trauma, trauma, or the use of c ...
, for instance tropicamide
Tropicamide, sold under the brand name Mydriacyl among others, is a medication used to dilate the pupil and help with examination of the eye. Specifically it is used to help examine the back of the eye. It is applied as eye drops. Effects occ ...
, or simply reducing the brightness of the ophthalmoscope, which may slightly increase natural mydriasis, allowing a better view of the posterior eye. It is primarily considered ophthalmologist or optometrist equipment, but is used by other specialists as well, including neurology and internal medicine. Recent developments like scanning laser ophthalmoscopy
Scanning laser ophthalmoscopy (SLO) is a method of examination of the eye. It uses the technique of confocal laser scanning microscopy for diagnostic imaging of the retina or cornea of the human eye.
As a method used to image the retina with a h ...
can make good quality images through pupils as small as 2 millimeters, so dilating pupils is no longer needed with these devices.
History
Dr. William Cumming in 1846 at the Royal London Ophthalmic Hospital (later Moorfields Eye Hospital
Moorfields Eye Hospital is a specialist NHS eye hospital in Finsbury in the London Borough of Islington in London, England run by Moorfields Eye Hospital NHS Foundation Trust. Together with the UCL Institute of Ophthalmology, which is adjacent ...
), of his pioneering work wrote "every eye could be made luminous if the axis from a source of illumination directed towards a person's eye and the line of vision of the observer were coincident".
Although some credit the invention of the ophthalmoscope to Charles Babbage
Charles Babbage (; 26 December 1791 – 18 October 1871) was an English polymath. A mathematician, philosopher, inventor and mechanical engineer, Babbage originated the concept of a digital programmable computer.
Babbage is considered ...
in 1847, it was not until it was independently reinvented by Hermann von Helmholtz
Hermann Ludwig Ferdinand von Helmholtz (31 August 1821 – 8 September 1894) was a German physicist and physician who made significant contributions in several scientific fields, particularly hydrodynamic stability. The Helmholtz Association, ...
in 1851 that its usefulness was recognized - it was to revolutionize ophthalmology.
While training in France, Andreas Anagnostakis
Andreas Anagnostakis (Ανδρέας Αναγνωστάκης; 11 August 1826 — 27 March 1897) was a Greek ophthalmologist, physician, and educator. He is best known for inventing the ophthalmoscope, a handheld tool used in diagnostics and s ...
, MD, an ophthalmologist from Greece, came up with the idea of making the instrument hand-held by adding a concave mirror. Austin Barnett 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, Francis A. Welch and William Noah Allyn invented the world's first hand-held direct illuminating ophthalmoscope, 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 Welch Allyn started as a result of this invention. In the 1970s a new ophthalmoloscope was developed with a larger primary lens allowing a 5x larger field-of-view, called the "Panoptic" or "pan ophthalmoscope".
Etymology and pronunciation
The word ''ophthalmoscopy'' () uses combining forms of '' ophthalmo-'' + '' -scopy'', yielding "viewing the eye". The word ''funduscopy'' () derives from '' fundus'' + '' -scopy'', yielding "viewing the far inside". The idea that ''fundus'' can and should correspond to a combining form ''fundo-'' drives the formation of an alternate form, ''fundoscopy'' (''fundo-'' + ''-scopy''), which is the subject of a descriptive
In the study of language, description or descriptive linguistics is the work of objectively analyzing and describing how language is actually used (or how it was used in the past) by a speech community. François & Ponsonnet (2013).
All acad ...
-versus-prescriptive
Linguistic prescription, or prescriptive grammar, is the establishment of rules defining preferred usage of language. These rules may address such linguistic aspects as spelling, pronunciation, vocabulary, syntax, and semantics. Sometimes infor ...
difference in acceptance. Some dictionaries enter the ''fundo-'' form as a second-listed variant, but others do not enter it at all, and one prescribes its avoidance with a usage
The usage of a language is the ways in which its written and spoken variations are routinely employed by its speakers; that is, it refers to "the collective habits of a language's native speakers", as opposed to idealized models of how a language ...
note.
See also
* Charles Schepens
Charles Louis Schepens (March 13, 1912 – March 28, 2006) was an influential Belgian (later American) ophthalmologist, regarded by many in the profession as "the father of modern retinal surgery",American Academy of Ophthalmology2003 Laureate A ...
* Retinoscope
Retinoscopy (Ret) is a technique to obtain an objective measurement of the refractive error of a patient's eyes. The examiner uses a retinoscope to shine light into the patient's eye and observes the reflection (reflex) off the patient's retina. W ...
* Scanning laser ophthalmoscopy
Scanning laser ophthalmoscopy (SLO) is a method of examination of the eye. It uses the technique of confocal laser scanning microscopy for diagnostic imaging of the retina or cornea of the human eye.
As a method used to image the retina with a h ...
References
External links
Ophthalmoscopy on Medlineplus
Ophthalmoscopy on WebMD
Overview at bmjjournals.com
about different types of ophthalmoscopy
{{Authority control
Diagnostic ophthalmology
Medical equipment
Ophthalmic equipment