Ultrasound of the eye is a method of diagnosing ophthalmic diseases, visualizing the structure of the eye, the condition of the ocular nerves, muscles and vessels, the lens, the retina. It is used as part of a comprehensive diagnosis of myopia, hyperopia, astigmatism, retinal dystrophy, cataract, glaucoma, eye tumors, injuries, vascular pathologies, neuritis. Several variants of the procedure are common: one-dimensional (A), two-dimensional (B), three-dimensional (AB) scanning, ultrasound / vascular ultrasound.
Ultrasound of the eye does not require advance preparation. Immediately before the procedure, it is necessary to remove makeup from the eyes, remove contact lenses. If there is a suspicion of the presence of a foreign body in the eye tissues, an X-ray of the eye is performed before the ultrasound examination. With the development of neoplasms of any etiology, preliminary diaphanoscopy or X-ray examination is recommended.
The result of ultrasound of the eye in A-scan mode is a one-dimensional image, the obtained parameters are used to calculate the strength of the intraocular lens before cataract removal surgery. With B-mode, a two-dimensional image of the eye sockets and eyeballs is obtained, the study reveals corneal opacities, cataracts, hemorrhages, foreign bodies, neoplasms in the eye. In the complex AV mode, the structures of the eye are displayed in a three-dimensional image. Vascular examination reflects the features of blood flow in real time through graphical and quantitative indicators. The following pathologies can be detected by ultrasound of the eye:
- Myopia, hypermetropia. The length of the anteroposterior axis of the eyeball is measured. With congenital myopia, it is more than normal, with farsightedness – less.
- Clouding of the lens. Normally, this structure is transparent and is not displayed on the monitor. When the lens becomes cloudy, it thickens and begins to reflect ultrasound waves – it becomes visible.
- Degenerative-dystrophic diseases. Retinal degeneration, optic nerve atrophy, glaucoma, keratopathy, conjunctival dystrophy are accompanied by thinning and cell death. In ultrasound images, the affected areas become less bright – from white and light gray to gray, barely detectable.
- Neoplasms, foreign body. The study allows you to determine the size and location of the tumor, a foreign object of the eye. With ultrasound, they look like areas of increased and high echo activity.
- Pathology of the optic nerves. Assessment of the state of the optic nerve fibers is necessary for retrobulbar neuritis, neurogenic tumors, glaucoma, traumatic lesions. The change in the thickness of the sheath and disc of the nerve, the expansion of certain parts of it, the blurring of the boundaries is determined.
- Vascular pathologies of the eye. Ultrasound of the ocular vessels is used to analyze blood flow in age-related, diabetic, atherosclerotic changes. The study reveals thrombosis of small and large vessels, nonperfused microvessels, vascular malformations, narrowing of the lumen, scarcity of branching, slowing of blood flow, twisting and undulating of vessels.
In addition to the above, ultrasound of the eye is prescribed to detect congenital anomalies of the development of the organ of vision, diseases of the lacrimal glands and lacrimal sac. Despite the high information content, ultrasound results cannot be the only confirmation of the diagnosis. They are used in combination with data from a clinical survey, anamnesis, ophthalmological examination, radiography and other instrumental methods.
Currently, ultrasound of the eye is the most informative and accessible method of early diagnosis of ophthalmic pathologies. The advantages of the method include harmlessness: the absence of radiation exposure and invasive intervention make it possible to conduct examinations of children, the elderly, pregnant women, nursing mothers. The short duration of the examination procedure and the relatively low cost make ultrasound one of the most common methods of screening for eye diseases. The disadvantage of ultrasound examination of the eye is that the image clarity is limited by the sensor area, the resolution is lower than with MRI and CT.