Ophthalmoscopy( examination of the fundus) - Causes, symptoms and treatment. MF.
Ophthalmoscopy is a method of examination that allows to examine the eyeball from the inside, i.e. To examine the fundus, using a special device - an ophthalmoscope. With the help of the method of ophthalmoscopy, it is possible to carefully examine the retina and the structures located in it: the area of the yellow spot, the central region of the retina, the optic nerve disk, the retinal vessels;as well as the choroid.
There are two types of ophthalmoscopy: direct and reverse. For ophthalmoscopy in the opposite form, an ophthalmoscope and 2 loops( +14 D or +30 D) are used. For direct ophthalmoscopy, only an ophthalmoscope is used without the use of loops. The reverse ophthalmoscopy differs from the direct one in the fact that in reverse ophthalmoscopy the picture of the fundus is represented in an inverted form: the upper part of the fundus is visible to the doctor from below, and the right side of the fundus is visible to the doctor on the left side. For the conduct of ophthalmoscopy in the reverse form, both a mirror and an electric ophthalmoscope can be used, and for the straight line only an electric ophthalmoscope can be used.
Indications for ophthalmoscopy
Any examination of an ophthalmologist is accompanied by an ophthalmoscopy. Examination of the fundus is an extremely important stage in the examination of the eyes. The choice of the type of this method of investigation depends on the expected pathology. Thus, various formations or hemorrhages in the retina, pathology in its macular zone, retinal detachment, as well as subtle changes in the optic nerve disk are better seen with direct ophthalmoscopy. A reverse ophthalmoscopy is preferable for retinopathy of prematurity, retinal dystrophy, and any other changes in the periphery of the retina, when a broad view is required. The choice of lens strength in reverse ophthalmoscopy also depends on the pathology. So a lens with a force of +14 D is preferable for examination of the optic disc and the macular area, and +30 D, when examining the peripheral parts of the fundus.
There are no contraindications to this method of examination.
Ophthalmoscopy procedure
No preparation is required for ophthalmoscopy. But for the most thorough examination of the periphery of the fundus, a preliminary dilatation of the pupil is required, which is achieved by instillation of 1% of the tropicamide solution 15 minutes before the test, or 0.5% of p-cyclopentolate.
Methods of direct ophthalmoscopy.
In a dark room, the patient sits on a chair. The doctor sits across from him. Then, putting an ophthalmoscope to his eye, and, lighting the eye of the patient with a beam of light, the doctor starts to approach the latter until he sees a clear picture of the fundus. The distance between the ophthalmoscope and the examined eye should not be more than 4 cm. But this method has a small drawback - during the inspection only a small section of the fundus is visible, therefore the doctor will direct the patient's view to fully examine the fundus, including his peripheraldepartments.
Reverse ophthalmoscopy technique.
The examination is also conducted in a dark room. The patient sits on a chair. A lamp should be placed to the left and somewhat behind the patient, the patient should be in the shade at the same time. The doctor sits in front of the patient, at arm's length, brings the ophthalmoscope to his eye, directing a ray of reflected light from the mirror to the pupil area. Thus the pupil starts to glow red. Then the doctor brings a biconvex magnifier to the patient's eye. When viewed, the magnifier is located at a distance of 7-8 cm from the eye being examined. This method is especially effective when examining the fundus in a person who has cataracts in the maturation stage. When using an electric ophthalmoscope, a lamp is not required.
For any kind of ophthalmoscopy, both eyes of the patient should be open.
During the examination, the doctor should examine various parts of the retina, which requires a certain position of the eyeball, in this regard, he will guide the position of the patient's gaze. Ophthalmoscopy is carried out in a certain order: first the doctor examines the area of the optic nerve disk, then the central area of the retina and, lastly, the periphery of the fundus. So, to examine the area of the optic nerve disc when examining the right eye, the patient should look at the doctor's right ear, when examining the left eye, respectively - on the left ear.
Normally, the optic nerve is round or oval in shape, pale pink in color, with clear contours. From the center of the disc comes the artery and enter the veins. The ratio of colibaarteria and veins in the healthy eye is 2: 3.To examine the central area of the retina, the patient should look directly into the ophthalmoscope. In the center of the fundus in the form of a red oval is a macula( or yellow spot) bordered by a light stripe( macular reflex) in its center is the central fovea of the retina corresponding to the foveal reflex. To examine the peripheral part of the retina, the doctor will ask the patient to look in 8 directions: up, up-left, left, down-left, down, down-right, right, up-right;for this it is necessary to first expand the pupil.
The procedure for ophthalmoscopy takes an average of 5-10 minutes.
It should be noted that during the examination the patient may experience some discomfort in the eyes due to the bright light from the ophthalmoscope, and immediately after the examination for some time the patient can see various spots before his eyes. If the pupil was dilated, then the steering wheel can not sit down for 2-3 hours after the examination, in addition, when entering the street, it is desirable for such a person to wear sunglasses. The dilated pupil causes severe discomfort when looking at the light.
Allergic reactions may occur on medications.
Doctor ophthalmologist Odinochko EA