RU2814028C1 - Method for diagnosing intraocular lens dislocation - Google Patents

Abstract

FIELD: ophthalmology.

SUBSTANCE: used to diagnose intraocular lens dislocation. To do this, meridional scanning is carried out using ultrasound biomicroscopy (UBM) in the range of 5-15 angular degrees, with the patient looking directly ahead, which is taken as the initial position. The patient is then asked to look away from direct look and back to the starting position. In this case, scanning is not interrupted and the position of the ultrasonic sensor is not changed. Using built-in programs, two scanograms are selected, the first of which is with direct look, the second scanogram after looking to the side, followed by looking back to its starting position. On both scanograms, using built-in programs, a line is drawn in the frontal plane passing through diametrically opposite points corresponding to the edges of the pigment leaf of the iris, which is taken as the base line. On the first scanogram, a perpendicular segment is drawn from any edge of the optical part of the intraocular lens (IOL) - the first segment, until it intersects with the baseline. The same is done on the second scanogram, but from the closest edge of the optical part of the IOL to the baseline, obtaining the second segment. If the first segment is larger than the second, then IOL dislocation is diagnosed.

EFFECT: ability to quickly and accurately determine the position of the structures of the anterior segment during physiological movement of the organ of vision for early diagnosis of IOL dislocation, which will allow timely selection of the correct tactics for further patient management.

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Description

The invention relates to ophthalmology, namely to ultrasound examination of the eye using high-frequency immersion biomicroscopy of the anterior part of the eye, and can be used to diagnose intraocular lens dislocation.

Despite the achievements of modern cataract surgery, various degrees of IOL dislocations detected in the early and late postoperative periods do not allow achieving the expected results of operations. Combined methods of timely treatment can improve the optical result of operations. The request of ophthalmology is the identification and assessment at an early stage of IOL dislocation, namely pseudophaco-iridodonesis, the possibility of registration, comparative analysis of cases, and increasing the sensitivity of methods.

The closest analogue of the proposed invention is a method for assessing the position of an intraocular lens (IOL) (RF patent for invention No. 2332932) which includes performing meridional scanning in the range of 5-15 angular degrees at a frequency of 35 MHz. The scanning result is assessed by measuring the deviation of the IOL elements relative to the anatomical structures of the eye in at least two meridians, in a static position of the eye at the time of measurement.

This method does not allow visualizing the position of the structures of the anterior segment of the eye during physiological movement of the organ of vision and thereby identifying pseudophaco-iridodonesis and promptly diagnosing IOL dislocations at an early stage.

The objective of the invention is to create an informative method for identifying and assessing the early stages of IOL dislocations, based on measuring the spatial relationships of the IOL with the structures of the organ of vision, visualizing the structures of the anterior segment of the eye using ultrasound biomicroscopy, when the patient's gaze changes.

The technical result of the proposed invention is the ability to quickly and accurately determine the position of the structures of the anterior segment during physiological movement of the organ of vision for early diagnosis of IOL dislocation, which will allow timely selection of the correct tactics for further patient management.

The technical result is achieved by applying the proposed method of ultrasonic biomicroscopy (UBM), which consists in assessing the dynamic relative position of the structures of the anterior segment of the eye.

The method is carried out in the following way. UBM is performed after preliminary epibulbar anesthesia. A funnel-shaped eyelid dilator is placed on the eye, which is filled with immersion liquid (saline solution, distilled water, keratoprotectors). An ultrasound sensor is inserted into the eyelid speculum and the underlying tissue is scanned in a given plane.

Initially, using ultrasound biomicroscopy, for example AVISO, a meridional scan of the eye is performed in the range of 5-15 angular degrees at a frequency of 50 MHz, with the patient looking straight ahead. Then the patient is asked to look away from direct gaze and back, which imitates the physiological movement of the eye. The operation of the ultrasound sensor and scanning registration are not interrupted. The position of the UBM sensor does not change when the eye deviates, leaving it in the direction when the patient is looking straight ahead. In the presence of pseudophaco-irdodonesis, a change in the position of the projection of the intraocular lens (IOL) in the anteroposterior direction is noted on the monitor screen.

The method is illustrated in Fig. 1-2. In fig. Figure 1 shows the scanogram when looking straight ahead (initial position). In fig. Figure 2 shows a scan after the eye has returned to its original position.

Two scans are selected to evaluate detected pseudophaco-iridodonesis. The first scanogram with the eye looking straight ahead (Fig. 1), the second scanogram after deviating the gaze to the side, followed by the return of the eye to its original position (Fig. 2). On scanograms, using built-in programs, a line is drawn in the frontal plane, passing through diametrically opposite points (A and A1), corresponding to the edges of the pigment leaf of the iris, which is taken as the base line. On the first scan, a perpendicular segment (B) is drawn from any edge of the optical part of the IOL until it intersects with the baseline. The same is done on the second scanogram, but from the closest edge of the optical part of the IOL to the baseline, obtaining segment (B1). The difference between segments B and B1 in millimeters is the amplitude of IOL movement, which makes it possible to objectively diagnose IOL dislocation at an early stage.

Example 1

Patient K., 65 years old.

Diagnosis: Right eye – pseudophakia.

Visual acuity 1.0.

6 months ago, phacoemulsification with posterior chamber IOL implantation was performed on the right eye. The operation and early postoperative period passed without complications.

The results of ultrasound biomicroscopy of the anterior part of the eye: the cornea, iris, angle of the anterior chamber, sclera, ciliary body and processes, the periphery of the retina have normal acoustic density and correct anatomical shape, the depth of the anterior chamber is 4.27 mm. Using the UBM, segments B and B1 were measured, which were 0.35 mm and 0.15 mm, respectively. Thus, the amplitude of IOL movement was 0.2 mm, which made it possible to objectively diagnose IOL dislocation at an early stage. The patient is recommended to have the IOL sutured to stop further progression of the IOL dislocation.

Example 2

Patient A., 60 years old.

Diagnosis: Right eye – pseudophakia.

Visual acuity 1.0.

5 months ago, phacoemulsification with posterior chamber IOL implantation was performed on the right eye. The operation and early postoperative period passed without complications.

The results of ultrasound biomicroscopy of the anterior part of the eye: the cornea, iris, angle of the anterior chamber, sclera, ciliary body and processes, the periphery of the retina have normal acoustic density and correct anatomical shape, the depth of the anterior chamber is 4.27 mm. Using the UBM, segments B and B1 were measured, which were 0.35 mm and 0.35 mm. The amplitude of IOL movement was 0 mm, and no dislocation of the intraocular lens was detected.

Claims (1)

A method for diagnosing dislocation of an intraocular lens, including performing a meridional scan using ultrasound biomicroscopy (UBM) in the range of 5-15 angular degrees, characterized in that the scan is carried out with the patient looking straight ahead, which is taken as the initial position, then the patient is asked to look away from the straight line gaze and back to the original position, without interrupting the scanning and without changing the position of the ultrasonic sensor, using built-in programs, two scanograms are selected, the first of which when the eye is looking straight, the second scanogram after deviating the gaze to the side with the subsequent return of the eye to its original position; on both scanograms, using built-in programs in the frontal plane, draw a line passing through diametrically opposite points corresponding to the edges of the pigment leaf of the iris, which is taken as the baseline; on the first scanogram, a perpendicular segment is drawn from any edge of the optical part of the intraocular lens (IOL) - the first segment, before intersecting with the baseline, the same is done on the second scanogram, but from the closest edge of the optical part of the IOL to the baseline, obtaining the second segment, and if the first segment is larger than the second, then IOL dislocation is diagnosed at an early stage.

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