Displacement of the artificial lens of the eye (IOL) after surgery (dislocation) - causes and treatment. Analysis of the causes of dislocation of the artificial lens and the results of treatment of patients. Filing of ioles to the iris complications.
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 determine the position of an intraocular lens (IOL). Meridian scanning is carried out in the range of 5-15 angular degrees at a frequency of 35 MHz and the orientation of the longitudinal axis of the IOL is determined by the location of the scanning plane in which the supporting elements are maximally distant from each other. The relative position of the optical axis of the eye and a line parallel to it passing through the center of the IOL is assessed, the relative position of the frontal plane passing through the ciliary sulcus and the horizontal plane of the optical element of the IOL is determined. The method allows you to quickly and accurately determine the localization of the IOL, the spatial relationships between the IOL and the structures of the anterior part of the eye, which increases the diagnostic information value of ultrasound biomicroscopy.
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CLASS="b560m"LIU YZ et al., Clinical applications of ultrasound biomicroscopy in diagnosis and treatment of lens subluxation, Zhonghua Yan Ke Za Zhi. 2004 Mar; vol.40(3), pp.186-189(abstract), [online], [found 08/30/2007], found from the PubMed database.
The invention relates to ophthalmology, namely to ultrasound examination of the eye using high-frequency immersion biomicroscopy of the anterior segment of the eye, and can be used to determine the position of an intraocular lens (IOL).
There is a known method for determining the degree of decentration of the artificial lens of the eye (IOC), based on biomicroscopic observation of the Purkinje reflexes from the anterior surface of the cornea and the anterior surface of the artificial lens of the eye. By measuring the distance between these two light marks using a measuring grid placed in the optical system of the biomicroscope, the degree of ICG decentration is determined (RU 2004100947, 2004).
The disadvantages of this method include the fact that its use is only possible while maintaining the transparency of the optical media and with small degrees of decentration within the pupil (i.e., when the optical element is visible in the pupil). In addition, the method does not allow determining the deviation of the IOL relative to the frontal axis (i.e., the tilt of the IOL), and also does not allow determining the interaction of the haptic elements of the IOL with the anatomical structures of the anterior segment of the eye (capsule, ciliary body, retina).
The closest analogue of the present invention is a method for assessing the position of the IOL, in particular the haptic elements of the IOL (Pavlin C.J., Rootman D., Arshinoff S., Harasiewicz K., Foster F.S. Determination of haptic position of transsclerally fixed posterior chamber intraocular lenses by ultrasound biomicroscopy, J. Cataract Refract Surg, 1993; 19; p.573-577), including ultrasound biomicroscopy at a frequency of 50 MHz. A radial scan is carried out in projections of the expected orientation of the haptic elements of the IOL and, when a cross-section of each haptic element is detected on the scan, its interaction with the anatomical structures of the anterior segment of the eye (capsule, iris, ciliary body) is determined.
However, limiting the scanning area to parameters of 4x4 mm does not allow one-time visualization of the entire anterior segment of the eye, does not make it possible to assess the location of the optical element of the IOL in relation to the haptics, as well as the relative position of the entire IOL with the axes and planes of the eye, therefore, does not provide a complete picture of the location IOL. In addition, with significant dislocations with partial displacement of the IOL into the vitreous body, a significant part of the lens is located outside the scanning zone and is not accessible to review.
The objective of the invention is to create an informative method for determining the position of the IOL based on developing the principles and parameters of visualization of the IOL and the anterior segment of the eye using ultrasound biomicroscopy.
The technical result of the present invention is the ability to quickly and accurately determine the localization of the IOL as a whole, with the establishment of spatial relationships between the IOL and the structures, axes and planes of the anterior segment of the eye with a corresponding increase in the diagnostic information content of ultrasound biomicroscopy, which makes it possible to assess the type and degree of dislocation of the IOL to select management tactics sick.
The technical result according to the invention is achieved through the use of the proposed scanning algorithm for pseudophakia, which consists in assessing the relative position of the IOL with the anatomical structures, axes and planes of the anterior part of the eye.
The method is carried out as follows. Initially, using an ultrasonic biomicroscope (for example, OTI Scan 1000, manufactured in Canada), a meridional scanning of the anterior part of the eye is carried out in the range of 5-15 angular degrees at a frequency of 35 MHz, which provides a simultaneous scanning area of 12x14 mm and a measurement accuracy of about 40 μm. In the resulting sections, the image of the optical and haptic elements of the IOL is identified. The distance between the haptic elements is measured and the orientation of the longitudinal axis of the IOL is determined by the location of the scanning plane in which the supporting elements are maximally distant from each other. Next, measurements are taken in two mutually perpendicular meridians, namely, through the center of the cornea and the center of the pupil, a line is drawn corresponding to the optical axis of the eye, and a line parallel to the first is drawn through the center of the optical element. The distance between these two lines in microns or millimeters characterizes the centration of the IOL. If at the same time in two mutually perpendicular meridians this distance is equal to 0, this clearly indicates the correct centration of the IOL. If it is >0, the linear value of dislocation (or decentration) of the IOL in two mutually perpendicular meridians is assessed. Then the location of the frontal plane passing through the ciliary groove is determined by drawing a line between two diametrically opposite points of the ciliary groove, and along the optical element of the IOL along its horizontal plane a second line is drawn until it intersects with the first, the angle between these two lines is estimated in degrees, which characterizes the relative position the frontal plane passing through the ciliary groove and the plane of the optical element of the IOL. If simultaneously in two mutually perpendicular meridians these lines are parallel and the angle is 0, the correct frontal position of the IOL is judged. If the angle is >0, a conclusion is drawn about the dislocation of the IOL with an inclination and the inclination angle is recorded in degrees.
Clinical examples
Example 1. Patient Z., 55 years old.
Diagnosis: Right eye - pseudophakia.
Visual acuity 1.0.
Three months ago, phacoemulsification of a cataract was performed on the right eye with implantation of a posterior chamber IOL. The operation and postoperative period proceeded 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. Pseudophakia, the IOL is placed in the capsular bag, the longitudinal axis of the IOL is oriented in the meridian from 13 to 7 o'clock. The IOL is in the correct position, since when scanning in two mutually perpendicular meridians it has a frontal position (namely, the horizontal plane of the IOL is parallel to the frontal plane of the eye passing through the ciliary sulcus) and is correctly centered (since the optical axis of the eye coincides with the line passing through the center of the IOL ).
Example 2. Patient N., 79 years old.
Diagnosis: Right eye - EED of the cornea, pseudophakia.
Visual acuity: counting fingers near the face
From the anamnesis: 9 years ago, extracapsular cataract extraction was performed with implantation of an IOL in the anterior chamber of the eye, with fixation of supporting elements in the corner of the anterior chamber.
With traditional biomicroscopy: the cornea is swollen, the contents of the anterior chamber cannot be visualized.
Results of ultrasound biomicroscopy: The cornea has increased echogenicity, thickened, thickness in the center is 680-700 µm, at the periphery - 810-890 µm. In the anterior chamber, an IOL is visualized, oriented in the horizontal meridian. The supporting elements rest against the corner of the anterior chamber.
The IOL is correctly centered relative to the optical axis of the eye and is in a frontal position. In the posterior chamber in the optical zone, elements of the capsule are absent; the remains of the lens masses of the equatorial zone are visualized.
Example 3. Patient R., 69 years old.
Diagnosis: Right eye - pseudophakia, IOL dislocation.
Visual acuity: 0.08 with correction sph -0.5 cyl -3.5 ax 167° = 0.3 n/k.
Three years ago, phacoemulsification of a cataract was performed on the right eye with implantation of a posterior chamber IOL. The operation and postoperative period proceeded without complications.
A month before treatment, the patient suffered a head injury, after which he noticed worsening vision. Traditional biomicroscopy revealed a displacement of the IOL; in the projection of the superonasal pupillary edge, the edge of the optical element of the IOL is visible.
Ultrasound biomicroscopy was performed to accurately determine the location and nature of IOL dislocation. The results of ultrasound biomicroscopy of the anterior part of the eye: the cornea, iris, anterior chamber angle, 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 4.63 mm. Pseudophakia, the longitudinal axis of the IOL is oriented in the meridian from 2 to 8 o’clock. The IOL is decentered relative to the optical axis of the eye along the horizontal meridian outward by 0.5 mm and along the vertical meridian downward by 1.9 mm. In addition, the lower-outer end of the IOL is deviated from the frontal plane, namely: in the meridian from 2 to 8 o’clock, the horizontal plane of the IOL and the frontal plane of the eye, passing through the ciliary sulcus, form an angle of 9 degrees, and in the perpendicular meridian from 10 to 4 o’clock - these planes are parallel. The haptic element in the superior nasal quadrant is located in the posterior chamber and touches the posterior surface of the iris in the 1-2 o'clock sector at a distance of 1.5 mm from the root of the iris, the haptic element in the inferotemporal quadrant is located in the vitreous body in the 7-8 o'clock sector projections of the border of the process and flat parts of the ciliary body at a distance of 2.8 mm distal to the limbus.
Example 4. Patient N., 64 years old.
Diagnosis: Left eye - pseudophakia, IOL dislocation.
Visual acuity: 0.5 n/k.
Seven days ago, phacoemulsification of a cataract was performed on the left eye with implantation of a posterior chamber IOL. During the operation, the posterior capsule of the lens ruptured. After partial anterior vitrectomy, the IOL was implanted on the duplicator of the peripheral part of the capsule layers.
Results of ultrasound biomicroscopy of the anterior part of the eye: in the 13-14 o'clock sector on the periphery of the cornea, a local thickening is visualized at the site of the surgical incision; throughout the rest of the cornea, as well as the iris, the angle of the anterior chamber, the sclera, the ciliary body and processes, the periphery of the retina has normal acoustic density and correct anatomical shape, the depth of the anterior chamber is 3.89 mm. Pseudophakia, the longitudinal axis of the IOL is oriented in the meridian from 9 to 3 o’clock. The IOL is correctly centered relative to the optical axis of the eye, since the latter in two mutually perpendicular meridians coincides with a line passing through the center of the IOL. However, the IOL is oriented obliquely, namely: the haptic element in the 3 o'clock meridian is deviated towards the posterior pole of the eye. In the horizontal meridian, the horizontal plane of the IOL and the frontal plane of the eye passing through the ciliary sulcus form an angle of 5 degrees, and in the perpendicular vertical meridian these planes are parallel. The reason for this inclination is the mixed fixation of the IOL, namely: in the 9 o'clock meridian, the haptic element is located in the ciliary groove at the root of the iris, and in the 3 o'clock meridian it is adjacent to the posterior surface of the ciliary processes at a distance of 1.55 mm distal to the limbus.
Example 5. Patient Sh., 68 years old.
Diagnosis: Left eye - pseudophakia, post-traumatic dislocation of the IOL.
Visual acuity: 0.08 with correction sph +9.5=0.3 n/k.
Three and a half years ago, extracapsular cataract extraction was performed on the left eye with implantation of a posterior chamber IOL. The operation and postoperative period proceeded without complications.
A week ago, the patient suffered an eye contusion, as a result of which his vision sharply deteriorated. Traditional biomicroscopy revealed a vitreous hernia and IOL dislocation, namely, the upper haptic element of the IOL is visible in the projection of the pupil.
To accurately determine the location and nature of IOL dislocation, ultrasound biomicroscopy of the anterior part of the eye was performed. Results: the cornea, iris, anterior chamber angle, sclera, ciliary body and processes, and the periphery of the retina have normal acoustic density and correct anatomical shape. In the anterior chamber, the profile of a vitreous hernia with rounded outlines is visualized, the distance from the cornea to the anterior surface of the hernia is 1.7 mm. Pseudophakia, the longitudinal axis of the IOL is oriented in the meridian from 13 to 6 o’clock. The IOL is decentered relative to the optical axis of the eye along the horizontal meridian outward by 1.5 mm and along the vertical meridian downward by 3.6 mm. In addition, on the inferotemporal side, the IOL is deviated from the frontal plane in the direction of the posterior pole of the eye: in the horizontal meridian the angle of inclination is 4.5 degrees, and in the vertical meridian it is 14.6 degrees. The upper haptic element is located behind the iris and touches it in the projection of the middle periphery, the distal end of the upper element is located in the plane of the pupil. The lower haptic element is displaced into the vitreous body and touches the inner wall of the eyeball; the point of contact is projected onto the sclera in the 6 o’clock meridian at a distance of 15 mm distal to the limbus.
Thus, the proposed method allows one to assess the position of the IOL in the eye with a high degree of accuracy for choosing patient management tactics.
FORMULA OF THE INVENTION
A method for assessing the position of an intraocular lens (IOL) in the anterior part of the eye, including ultrasound biomicroscopy, characterized in that a meridional scanning of the anterior part of the eye is carried out in the range of 5-15 angular degrees at a frequency of 35 MHz and the position of the IOL is assessed by determining the orientation of the longitudinal axis of the IOL along the location of the scanning plane in which the supporting elements are as far apart as possible, by assessing the relative position of the optical axis of the eye and a line parallel to it passing through the center of the IOL, by determining the relative position of the frontal plane passing through the ciliary sulcus and the horizontal plane of the optical element of the IOL.
This is a fairly serious complication, as it may be accompanied by loss of the vitreous body, posterior migration of the lens masses and, less commonly, expulsive bleeding. If not treated appropriately, long-term consequences of vitreous loss include a pulled-up pupil, uveitis, vitreous opacities, wick syndrome, secondary glaucoma, posterior dislocation of the artificial lens, retinal detachment, and chronic cystoid macular edema.
Signs of posterior capsule rupture
Sudden deepening of the anterior chamber and instantaneous dilatation of the pupil. Failure of the nucleus, inability to pull it to the tip of the probe. Possibility of vitreous aspiration. The ruptured capsule or vitreous body is clearly visible.
Tactics depend on the stage of the operation at which the rupture occurred, its size and the presence or absence of vitreous prolapse. The basic rules include:
introduction of viscoelastic behind the nuclear masses in order to bring them into the anterior chamber and prevent vitreous hernia; insertion of a special gland behind the lens masses to close the defect in the capsule; removal of lens fragments by introducing viscoelastic or removing them using phaco; complete removal of the vitreous from the anterior chamber and the incision area using a vitreotome; The decision to implant an artificial lens should be made taking into account the following criteria:
If large quantities of lens masses have entered the vitreous cavity, an artificial lens should not be implanted, as it may interfere with fundus visualization and successful pars plana vitrectomy. Artificial lens implantation can be combined with vitrectomy.
If there is a small tear in the posterior capsule, careful implantation of a CD-IOL into the capsular bag is possible.
In case of a large tear and especially with an intact anterior capsulorhexis, it is possible to fix the CB-IOL in the ciliary groove with the optical part placed in the capsular bag.
Insufficient capsule support may necessitate sulcus suturing of the intraocular lens or implantation of a glide-assisted PC IOL. However, PC IOLs are associated with more complications, including bullous keratopathy, hyphema, iris folds, and pupil irregularity.
Dislocation of lens fragments
Dislocation of lens fragments into the vitreous body after rupture of the zonular fibers or posterior capsule is a rare but dangerous phenomenon, as it can lead to glaucoma, chronic uveitis, retinal detachment and chronic cystoid macular edema. These complications are more often associated with phaco than with EEC. Initially, treatment for uveitis and glaucoma must be carried out, then the patient should be referred to a vitreoretinal surgeon for vitrectomy and removal of lens fragments.
NB: There may be cases where it is not possible to achieve the correct position even for a PC IOL. Then it is safer to refuse implantation and decide to correct aphakia with a contact lens or secondary implantation of an intraocular lens at a later date.
The timing of the operation is controversial. Some suggest removing residues within 1 week, since later removal affects the restoration of visual function. Others recommend postponing surgery for 2-3 weeks and undergoing treatment for uveitis and increased intraocular pressure. Hydration and softening of the lens masses during treatment facilitates their removal using a vitreotome.
Surgical techniques include pars plana vitrectomy and removal of soft fragments with a vitreotome. More dense fragments of the nucleus are connected by the introduction of viscous liquids (for example, perfluorocarbon) and further emulsification with a phragmatome in the center of the vitreous cavity or removal through a corneal incision or scleral pocket. An alternative method for removing dense nuclear masses is their crushing followed by aspiration,
Dislocation of the GK-IOL into the vitreous cavity
Dislocation of the GC IOL into the vitreous cavity is a rare and complex phenomenon, indicating improper implantation. Leaving an intraocular lens in place can lead to vitreal hemorrhage, retinal detachment, uveitis, and chronic cystoid macular edema. Treatment is vitrectomy with removal, reposition or replacement of the intraocular lens.
With adequate capsular support, repositioning of the same intraocular lens into the ciliary sulcus is possible. With inadequate capsular support, the following options are possible: removal of the intraocular lens and aphakia, removal of the intraocular lens and replacing it with a PC-IOL, scleral fixation of the same intraocular lens with a non-absorbable suture, implantation of iris-clip lenses.
Hemorrhage into the suprachoroidal space
Hemorrhage into the suprachoroidal space may be a consequence of expulsive bleeding, sometimes accompanied by prolapse of the contents of the eyeball. This is a serious but rare complication and is unlikely to occur with phacoemulsification. The source of hemorrhage is a rupture of the long or posterior short ciliary arteries. Contributing factors include advanced age, glaucoma, anterior-posterior enlargement, cardiovascular disease, and vitreous loss, although the exact cause of bleeding is not known.
Signs of suprachoroidal hemorrhage
Increasing fragmentation of the anterior chamber, increased intraocular pressure, iris prolapse. Leakage of the vitreous body, disappearance of the reflex and the appearance of a dark tubercle in the pupil area. In acute cases, the entire contents of the eyeball may leak through the incision area.
Immediate actions include closing the incision. Posterior sclerotomy, although recommended, may increase bleeding and lead to loss of the eye. After surgery, the patient is prescribed local and systemic steroids to relieve intraocular inflammation.
Follow-up tactics
Ultrasound examination is used to assess the severity of changes that have occurred; surgery is indicated 7-14 days after blood clots have liquefied. The blood is drained and vitrectomy is performed with air/fluid exchange. Despite the unfavorable prognosis for vision, in some cases it is possible to preserve residual vision.
Edema
The swelling is usually reversible and is most often caused by the operation itself and injury to the endothelium through contact with instruments and the intraocular lens. Patients with Fuchs endothelial dystrophy pose an increased risk. Other causes of edema include the use of excessive power during phacoemulsification, complicated or prolonged surgery, and postoperative hypertension.
Iris prolapse
Iris prolapse is a rare complication of small incision surgery but can occur with EEC.
Causes of iris loss
The incision for phacoemulsification is closer to the periphery. Moisture leaking through the cut. Poor suture placement after EEC. Patient-related factors (cough or other strain).
Symptoms of iris loss
On the surface of the eyeball in the area of the incision, prolapsed iris tissue is detected. The anterior chamber at the incision site may be shallow.
Complications: uneven wound scarring, severe astigmatism, epithelial ingrowth, chronic anterior uveitis, macular edema and endophthalmitis.
Treatment depends on the interval between surgery and detection of prolapse. If the iris falls out within the first 2 days and there is no infection, its reposition with repeated suturing is indicated. If the prolapse occurred a long time ago, the area of the prolapsed iris is excised due to the high risk of infection.
Intraocular lens displacement
Displacement of the intraocular lens is rare, but can be accompanied by both optical defects and disturbances in the structures of the eye. When the edge of the intraocular lens is displaced into the pupil area, patients are bothered by visual aberrations, glare and monocular diplopia.
Intraocular lens displacement mainly occurs during surgery. It can be caused by dialysis of the ligament of Zinn, capsule rupture, and can also occur after conventional phacoemulsification, when one haptic part is placed in the capsular bag and the second in the ciliary groove. Postoperative causes include trauma, irritation of the eyeball and contraction of the capsule.
Treatment with miotics is beneficial for minor displacement. Significant displacement of the intraocular lens may require replacement.
Rheumatogenous retinal detachment
Rheumatogenous retinal detachment, although rare after EEC or phacoemulsification, may be associated with the following risk factors.
Before surgery
Lattice degeneration or retinal breaks require pretreatment before cataract extraction or laser capsulotomy if ophthalmoscopy is possible (or immediately after it becomes possible). High myopia.
During surgery
Vitreous loss, especially if subsequent management was incorrect, and the risk of detachment is about 7%. If myopia is >6 diopters, the risk increases to 1.5%.
After surgery
Performing YAG laser capsulotomy in the early stages (within a year after surgery).
Cystoid retinal edema
Most often it develops after a complicated operation, which was accompanied by rupture of the posterior capsule and prolapse, and sometimes strangulation of the vitreous, although it can also be observed during a successfully performed operation. Usually appears 2-6 months after surgery.
General description
Diagnosis of cataracts
Conservative or drug treatment of cataracts
Cataract - surgical treatment
Modern eye microsurgery
Postoperative complications in cataract treatment
Recommendations for patients after cataract removal in the postoperative period
An operation to remove a clouded lens (cataract), performed by an experienced ophthalmic surgeon, is, in principle, a simple, safe and quick operation, although, like any surgical intervention, it does not exclude the possibility of developing some complications.
Types of complications after surgery
All complications of cataract surgery can be divided into those that occurred during surgery or intraoperative and immediately postoperative.
In turn, postoperative complications, depending on the timing of their occurrence, can be divided into early and late. Statistics show a small percentage of postoperative complications: no more than 1.5% of cases.
Early postoperative complications include:
Iridocyclitis, uevitis – inflammatory eye reactions; Increased intraocular pressure; Hemorrhage into the anterior chamber; Retinal detachment; Dislocation or displacement of the artificial lens.
Learn more about each complication
The response of the eye to surgical trauma is called the inflammatory reaction. Prevention of this complication always begins at the final stages of the operation, for which broad-spectrum antibiotics and steroid drugs are injected under the conjunctiva of the eye.
During the normal course of the postoperative period, i.e. without complications, and against the background of anti-inflammatory therapy, after 2-3 days all symptoms of the body’s response to surgical intervention disappear: the function of the iris and the transparency of the cornea are completely restored, and since the picture of the fundus becomes clear, ophthalmoscopy becomes possible.
Hemorrhage into the anterior chamber is a fairly rare complication and is associated with damage or trauma to the iris during surgery. In these cases, against the background of the treatment, the blood is absorbed, as a rule, within a few days, and otherwise, i.e., if conservative therapy is ineffective, the anterior chamber is washed and additional fixation of the lens is performed (if necessary).
Intraocular pressure
An increase in intraocular pressure in the postoperative period may occur due to: the development of pupillary block, or clogging of the drainage system with special viscous preparations - highly elastic, used at all stages of the operation to protect intraocular structures and, especially, the cornea of the eye, if they are incompletely washed out of the eye .
In this case, when intraocular pressure rises, drops are prescribed, and this is usually sufficient. Only in rare cases, when intraocular pressure increases in the early postoperative period, an additional operation is performed - puncture (puncture) of the anterior chamber and its thorough rinsing.
Retinal detachment
Retinal detachment occurs with the following predisposing factors:
myopia,
eye injury in the postoperative period, complications during surgery.
Treatment of such a complication is most often surgical: an operation is performed to seal the sclera using a silicone sponge - vitrectomy. When retinal detachment occurs on a surface of a small area, restrictive laser coagulation of the retinal tear is performed.
Violation of the position of the optical part of the artificial lens negatively affects the functions of the operated eye. Such displacements can be caused by improper fixation of the lens in the capsular bag or disproportion between the supporting elements of the lens and the size of the capsular bag.
When the lens is decentered or slightly displaced, patients complain of discomfort in the operated eye, fatigue after eye strain, and double vision often appears when looking into the distance.
As a rule, these complaints are not constant and disappear after a short rest. But with a significant displacement of the IOL, more than 0.7 - 1 mm, there is constant double vision when looking into the distance and constant visual discomfort. Moreover, the gentle visual mode of operation does not give any effect. With similar symptoms, repeated surgery is required to correct the position of the optical part of the artificial lens.
Full IOL displacement
Complete displacement of the IOL is a dislocation of the lens either anteriorly, into the anterior chamber, or vice versa posteriorly, into the vitreous cavity. This complication is considered severe and requires vitrectomy - a surgical intervention in which the artificial lens is lifted from the fundus of the eye and re-fixed in the correct position.
When the lens is displaced anteriorly, the operation is simpler; it requires re-insertion of the IOL into the posterior chamber with its further suture fixation.
Late postoperative complications include:
Irvine-Gass syndrome (swelling of the central retina);
Secondary cataract.
Swelling of the retinal area
One of the complications during operations on the anterior segment of the eye is swelling of the macular region of the retina. Most often, this complication develops after traditional extracapsular cataract extraction rather than after phacoemulsification and occurs within 4 to 12 weeks after the operation.
The risk of developing this complication increases if the patient has:
diabetes mellitus,
glaucoma,
inflammation of the choroid of the eye,
previous eye injuries, etc.
Reasons for the formation of secondary cataracts
A fairly common late complication during cataract surgery is secondary cataract. The reason for the formation of secondary cataracts is the migration from the growth zone, which is located in the equator region, to the central optical zone of opaque, irregularly shaped, structurally defective Adamyuk-Elschnig ball cells, from which a film or turbidity is formed, which reduces visual acuity, sometimes quite significantly.
A decrease in visual acuity, in addition, may be due to the process of fibrosis of the lens capsule, a natural process that occurs a certain time after the operation. And these periods of formation of secondary cataracts vary from several months to several years.
Prevention and treatment of secondary cataracts
To prevent the formation of such complications as secondary cataracts, special techniques are used:
selection of IOLs of special designs, “polishing” of the lens capsule to remove cells (as complete as possible), etc.
Treatment of secondary cataracts involves performing a posterior capsulotomy. This manipulation consists of creating a hole in the posterior capsule of the lens, which frees the central optical zone from clouding and allows light rays to freely penetrate into the eye, thereby increasing visual acuity, and significantly.
Capsulotomy is performed either using a laser or by mechanically removing the film using surgical instruments. Performing capsulotomy using a laser is preferable, since there is no insertion of a surgical instrument into the eye, but this method also has a number of disadvantages, the main one of which is the possibility of damage to the optical part of the artificial lens by laser radiation. In addition, there are a number of clear contraindications to this procedure.
Both laser and surgical capsulotomy are performed on an outpatient basis and allow the patient to return high visual acuity in just a few minutes, provided that the patient’s neuroreceptor apparatus of the optic nerve and retina is intact.
People who have had to deal with such an ophthalmological problem as lens opacity know that the only way to get rid of it is cataract surgery, that is, IOL implantation. In the United States, more than 3 million such operations are performed per year, and 98% of them are successful. In principle, this operation is simple, quick and safe, but it does not exclude the development of complications. What complications may arise after cataract surgery and how to correct them, we will find out by reading this article.
All complications that accompany IOL implantation can be divided into those that occurred directly during surgery or postoperatively. Postoperative complications include:
increase in intraocular pressure; uevitis, iridocyclitis - inflammatory ocular reactions; retinal detachment; hemorrhage in the anterior chamber; displacement of the artificial lens; secondary cataract.
Inflammatory eye reactions
Inflammatory responses almost always accompany cataract surgery. That is why, immediately after the completion of the intervention, steroid drugs or broad-spectrum antibiotics are injected under the conjunctiva of the patient’s eye. In most cases, after about 2-3 days, symptoms of the response will completely disappear.
Hemorrhage into the anterior chamber
This is a fairly rare complication that is associated with trauma or damage to the iris during surgery. Usually the blood resolves on its own within a few days. If this does not happen, doctors rinse the anterior chamber and, if necessary, additionally fix the lens of the eye.
Increase in intraocular pressure
This complication may occur due to clogging of the drainage system with highly elastic, viscous drugs that are used during surgery to protect the cornea and other intraocular structures. Usually, instilling drops that reduce intraocular pressure solves this problem. In exceptional cases, it becomes necessary to puncture the anterior chamber and thoroughly rinse it.
Retinal detachment
This complication is considered severe, and it occurs in the event of an eye injury after surgery. In addition, retinal detachment is most common in people with myopia. In this case, ophthalmologists most often decide to perform an operation, which consists of filling the sclera - vitrectomy. In the case of a small area of detachment, restrictive laser coagulation of the retinal tear can be performed. Among other things, retinal detachment leads to another problem, namely lens displacement. Patients begin to complain about rapid eye fatigue, pain, and double vision when looking into the distance. These symptoms are not permanent and usually disappear after a short rest. When a significant displacement occurs (1 mm or more), the patient feels constant visual discomfort. This problem requires repeated intervention.
Full Lens Shift
Dislocation of the implanted lens is considered the most severe complication, which requires unconditional surgical intervention. The operation involves lifting the lens and then fixing it in the correct position.
Secondary cataract
Another complication after cataract surgery is the formation of secondary cataracts. It occurs due to the proliferation of remaining epithelial cells from the damaged lens, which spread to the area of the posterior capsule. The patient experiences deterioration in vision. To correct this problem, it is necessary to undergo a laser or surgical capsulotomy procedure. Take care of your eyes!
Relevance
In cataract surgery, in some cases, a complication of the early or late postoperative period is the dislocation of the intraocular lens (IOL) and its partial or complete luxation into the vitreous body, which occurs when the lens capsule ruptures and the ligamentous-capsular apparatus of the lens fails. This raises the question of the possibility of safe reposition and reliable fixation of the IOL.
Currently, there are various ways to reposition or replace dislocated IOLs: suturing to the iris, various options for suturing to the sclera with and without a scleral flap, replacing a posterior chamber IOL with an anterior chamber one or an IOL with iridopupillary fixation. Each of these methods has its own advantages and disadvantages.
Replacing a posterior chamber IOL with an anterior chamber one often leads to damage to the trabecular apparatus, low-grade inflammatory processes in the eye and, as a consequence, to secondary glaucoma, as well as to the development of corneal EED.
Pupillary fixation of IOLs also has significant disadvantages associated with impaired diaphragmatic function of the iris; there is a risk of developing pupillary block, iridocyclitis, and macular edema. When the pupil dilates, complete or partial dislocation of the IOL into the anterior chamber with the development of EED or into the vitreous body is possible, which forces additional fixation of the IOL with sutures to the iris and limits pupillary function.
A number of scientific works are devoted to the reposition and fixation of the most physiological posterior chamber IOLs to the sclera in order to avoid further dislocation of the IOL into the vitreous body. In addition, such IOL fixation becomes the only alternative in complicated pseudophakia, when implantation of an anterior chamber or iris clip lens is contraindicated due to pronounced changes in the anterior segment of the eye (presence of anterior synechiae, iridodialysis, partial or complete aniridia).
Various methods of repositioning and intrascleral fixation of IOLs make it possible to obtain good fixation of IOLs, but are not always the method of choice, as they are associated with risks of complications such as hemophthalmos, ocular hypertension, and suture protrusion. Most proposed methods for IOL repositioning involve the use of various viscoelastics during surgery, which increases the likelihood of ocular hypertension after surgery. In this regard, careful washing of the viscoelastic is required. However, its washing out is associated with additional trauma to the cornea and an increase in the risk of developing EED, which is already initially elevated in eyes with a similar pathology. The search for new methods of reposition, reliable fixation of IOLs and reducing the risk of complications is relevant.
Target
To improve the technique of repositioning and reliable intrascleral fixation of IOLs without the use of viscoelastics.
Tasks:
1. Develop a technique for repositioning and fixing IOLs in various complicated clinical situations.
2. Assess the results of the developed surgical intervention.
Material and methods
We observed 67 patients (72 eyes) aged from 52 to 89 years with dislocation of the posterior chamber IOL. Observation periods are up to 10 years. IOL dislocation with rupture of the lens capsule - 29 eyes. Dislocation of the IOL together with the capsular bag - 43 eyes. All patients underwent surgery using the microinvasive technique we developed without the use of viscoelastic. In 5 patients, concomitant pathology of the posterior segment of the eye was observed. The following types of IOLs were repositioned: Alcon Acrysof IQ Natural, Acrysof three-piece, Rayner aspheric, Akreos AO, Hanita lenses. To fix the IOL after its reposition, we used the sclerocorneal method of IOL fixation, developed by us, which allows for reliable fixation of almost any type of the most commonly used IOL. Visual acuity before surgery ranged from 0.01 to 0.7 with correction (average 0.28±0.06). IOP - from 14 to 25 mm Hg.
Surgery technique: first, 2 through punctures of the sclera and ciliary body were made oppositionally in one of the oblique meridians 2.5 mm from the limbus with a 25 or 23G needle. Two limbal corneal paracentesis were formed over the puncture sites. And in the perpendicular oblique meridian there are 2 more limbal paracentesis of the cornea. Through one scleral puncture, a needle with a thread was passed in the form of a loop, back first, over the IOL, without touching the IOL. The dorsal part of the needle was then withdrawn through one of the corneal paracenteses. Then, a 25 or 23G guide needle was inserted exactly into the site of the same scleral puncture, which was used to center the IOL and which was inserted behind one haptic element of the IOL. The cutting part of the needle and thread was passed through the guide needle and brought out. Then a “noose” loop was formed from the outside, which was tightened on the haptic element of the IOL. Then the needle and thread were inserted exactly into the site of the scleral injection and carried out intrasclerally and intracorneally through both lips of the paracentesis. The needle and thread were removed from the paracentesis with its back side outwards. An “anchor” knot was formed, the remainder of the thread and needle was cut off, and the knot was immersed in paracentesis. The same surgical actions were performed on the opposing side. Since no incisions were made in the sclera and conjunctiva, after the operation there were no stitches left on the eye that would need to be removed later.
Results
In 69 cases, central stable fixation of the IOL was achieved. In 3 cases, decentration of the IOL up to 1.0 mm was observed, which did not affect the outcome of the operation. Re-fixation of the IOL was not required in any case. Visual functions in patients corresponded to the initial situation before IOL dislocation and the degree of preservation of the optic nerve and retinal layers. Visual acuity ranged from 0.2 to 1.0 with correction (average 0.78±0.08). IOP after surgery was from 11 to 23 mmHg. in 68 cases. In 4 cases, transient ocular hypertension of up to 26 and 37 mm Hg was observed, relieved with drops for 1.5 months.
Conclusions
1. The developed technique for repositioning posterior chamber IOLs is safe and allows for reliable fixation.
2. The sclerocorneal method of IOL fixation without the use of viscoelastic can minimize the risk of complications, in particular, reduce the likelihood of postoperative hypertension.
20-10-2012, 12:54
Description
More often dislocation of the lens in the CT occurs as a result of injury. Rupture of the ligaments of Zinn can occur with both penetrating injury and blunt trauma to the eye. When the ligamentous apparatus is weak, lens dislocation sometimes occurs as a result of a sharp shock to the body (scorching, blow). Spontaneous dislocation of the lens in the CT is often observed in Marfan syndrome. In some cases, the entire lens is displaced into the CT during cataract extraction due to rupture of the zonules of Zinn, or the nucleus sinks when the posterior capsule is ruptured. CT liquefaction plays a major role in the pathogenesis of lens dislocation.Zinn ligament rupture may be incomplete. In these cases, the lens dislocated in the ST is fixed in the parietal layers of the ST, usually at the bottom. With complete rupture of the ligaments and significant liquefaction of the CT, the lens can become mobile, moving freely in the vitreal cavity. When the pupil dilates, such a lens can extend into the anterior chamber if the patient assumes a “face down” position. Deprived of the influence of the zonules of Zinn, mobile lenses usually have a spherical shape; they often remain transparent for a long time, but sometimes quickly become cloudy.
Lens dislocation can cause serious complications. Especially often an increase in IOP develops, which is almost not amenable to drug treatment. Severe uveitis, retinal detachment, and hemorrhages often occur. The best method for preventing and treating these complications is transciliary removal of the luxated lens with simultaneous vitrectomy. The surgical technique depends on the density of the lens nucleus. If the lens is soft, its removal does not present much difficulty and is carried out with a vitreotome. For hard lenses, ultrasound or laser phacoemulsification must be used.
Operation technique . After separating the conjunctiva, three sclerotomies are performed, as usual, 3.0 mm from the limbus. The infusion cannula is sutured, a vitreotome and an endoilluminator are inserted into the CT. A dislocated lens is usually found in the fundus.
In young patients, the lens is soft and is removed by lensectomy directly into the CT cavity. If the lens is mobile, then the vitreotome opening should be brought close to it and aspiration should be turned on (Fig. 17.1).
Rice. 17.1. Position of the vitreotome before aspiration
In this case, it is necessary to ensure that the CT fibers do not get between the lens and the vitreotome. The lens, held by aspiration, must be brought to the anterior sections of the CT. Without reducing aspiration, you should briefly turn on the cutting and destroy the capsule. In this case, the vitreotome and the endilluminator must be placed under the lens to prevent it from falling onto the fundus. Using mainly aspiration, with only occasional cutting, the contents of the lens can be removed (Fig. 17.2).
Rice. 17.2. Lensectomy of a luxury lens raised to the anterior sections of the CT
The capsular bag should be removed last in cutting mode with maximum aspiration.
After completion of the lensectomy, removal of CT. During vitrectomy, those fragments of the lens that could be lost during lensectomy are also removed (Fig. 17.3).
Rice. 17.3. Removal of lens remnants during vitrectomy
In cases where the lens is fixed, a vitrectomy should first be performed to remove the CT surrounding the lens and free it. Only after mobilization of the lens can it be lifted into the anterior sections of the CT without fear of traction on the retina.
To remove a lens with a dense core it is necessary to perform a vitrectomy first(Fig. 17.4).
Rice. 17.4. Vitrectomy for a dense lens
When crushing the dense nucleus using ultrasonic emulsification, the lens should be removed to the anterior sections of the CT cavity. For this purpose, PFOS is introduced into the ST, starting at the optic disc, so that there is no fragmentation and it is introduced as a single mass. In order to prevent an increase in IOP, it is necessary to close the infusion and ensure fluid drainage above the PFOS level. Since the specific gravity of the lens is less than PFOS, it floats to the surface.
Phacoemulsification in the anterior sections of the CT is safer than in the anterior chamber, where there is a risk of damage to the iris and corneal endothelium. The lens floating on the surface of PFOS is very mobile, which makes phacoemulsification difficult. To fix the lens it is necessary to use an additional instrument inserted instead of an endoilluminator, which is no longer necessary when working in the anterior sections of the CT; the illuminators of an operating microscope are sufficient. An additional instrument can be either a vitreoretinal knife or an injection needle. The lens is first held using phacoemulsification aspiration, then a knife or needle is inserted in the area of its equator, and after this, ultrasound can be turned on and destruction of the lens can begin (Fig. 17.5).
Rice. 17.5. Phacoemulsification of a luxated lens elevated with PFOS. The lens is fixed with an injection needle
During phacoemulsification in CT, an elongated tip without an irrigation silicone sleeve is used, which allows the instrument to be used through a sclerotomy in the flat part of the ciliary body. The fluid is supplied through an infusion cannula, as happens during vitrectomy.
It is difficult to destroy and remove a very hard nucleus using an ultrasonic phacoemulsifier. Better to use laser phacoemulsifier. After vitrectomy, the chrus alik is raised with the help of PFOS into the anterior sections of the VT. A laser light guide is inserted through one sclerotomy, and an aspiration cannula is inserted through the second. The lens is held in the center by these two instruments, while under the influence of laser energy the lens is destroyed, and the crushed particles are removed from the eye through a suction cannula.
In cases where difficulties arise with lens mobility, you need to bring it into the anterior chamber. To do this, PFOS is added so that the floating lens appears in the pupil area. Using a suction cannula and a PFOS injection cannula, the lens is brought through the pupil into the anterior chamber. The lens, supported by PFOS from the CT side, cannot leave the anterior chamber regardless of the width of the pupil. Now it can be removed using laser phacoemulsification.
If this method is not possible, then the lens is removed through a corneal or corneoscleral incision. To do this, use plugs to close the sclerotomy, open the anterior chamber with a disposable blade, and turn off the infusion (Fig. 17.6).
Rice. 17.6. Making a corneal incision
After the anterior chamber is opened, viscoelastic must be injected to protect the corneal endothelium. The incision is widened, viscoelastic is inserted behind the lens, and the latter begins to emerge into the wound. At this moment, you need to apply pressure on the posterior lip of the incision, facilitating the removal of the lens. A running 10-0 nylon suture is placed over the corneal incision (Fig. 17.7).
Rice. 17.7. Removal of the luxated lens through a corneal incision
In all cases where PFOS was used, after removing the lens in one way or another, PFOS must also be removed. To do this, you need to open the sclerotomy and insert an endoilluminator and an L-shaped cannula connected to a free silicone tube. The cannula is brought to the optic disc under visual control and the infusion is started. Under the pressure of the infusion fluid, PFOS is forced out of the eye through the cannula. The operation is completed by suturing the sclerotomies and conjunctival incisions.
Removing the lens luxated in the CT through the pars plana of the ciliary body is a fairly simple and effective technique. Timely and successful implementation of this intervention helps prevent the development of severe complications associated with the presence of a moving lens in the eye.
Dislocation of the intraocular lens
If the IOL is dislocated in the CT, it should be either repositioned or, if this is not possible, removed. In any case, vitrectomy is necessary. It is relatively easy to put a lux iris clip lens in place.
Dilate the pupil before surgery, it is necessary to use short-acting mydriatics (mydriation, neosynephria). First, a standard vitrectomy is performed through three sclerotomies using a sutured infusion cannula and an endoilluminator (Fig. 17.8).
Rice. 17.8. Vitrectomy for IOL dislocation
The IOL is freed from the CT fibers, grasped with vitreal forceps and brought into the anterior chamber (Fig. 17.9).
Rice. 17.9. Lifting the IOL from the fundus using vitreous tweezers
The endoilluminator is removed from the eye, and an acetylcholine solution is injected into the anterior chamber through the vacated sclerotomy to constrict the pupil and hold the IOL in the anterior chamber (Fig. 17.10).
Rice. 17.10. Removing the IOL into the anterior chamber using vitreal tweezers, introducing an acetylcholine solution
After removal of the vitreal forceps, the sclerotomies are closed with plugs. Using a disposable blade, two paracenteses are performed. If the IOL is not positioned correctly, then after closing the infusion and introducing viscoelastic correct its position, for example, tucking the bow. To do this, a spatula is inserted through one paracentesis, with the help of which the IOL is moved to the side, and through the other, a hook is inserted, with which I pull back the pupillary edge under the arch. Then you need to press the arm with a spatula, move it behind the iris and center the IOL. In order to prevent dislocation of the IOL in the future, you need to suture it to the iris by applying two interrupted sutures.
A stab needle and 10-0 monofilament suture should be used to suture the IOL to the iris. Preference should be given polypropylene seam, which dissolves in the iris tissue much more slowly than nylon. Through paracentesis, the end of a one-ton needle is passed into the anterior chamber. In order to avoid stitching the corneal tissue, it is necessary to make lateral movements with the needle, making sure that it passes freely through the paracentesis. After the end of the needle appears in the anterior chamber, you need to make a deep puncture of the iris near the arch, pass the needle under it and make a puncture through the iris. Moving the needle further, it is necessary to pierce the cornea. When the end of the needle appears on the surface of the cornea, it is grabbed by the needle holder and the needle is removed (Fig. 17.11).
Rice. 17.11. Summing the pupillary lens, the needle passes through the iris, capturing the IOL arm
Thus, the suture thread enters the anterior chamber through paracentesis, passes through the iris, goes around the arch, returns through the iris to the anterior chamber and leaves the eye through the cornea. The thread together with the needle must be cut 10.0-15.0 mm from the cornea. Using a microhook, it is necessary to pull this end into a paracentesis (Fig. 17.12).
Rice. 17.12. Pulling the thread from the anterior chamber with a microhook through paracentesis
Now that both ends of the suture are together, the knot can be tightened and the IOL arm will be sutured to the iris (Fig. 17.13).
Rice. 17.13. Tightening the knot
Another suture should be placed in the same way through the second paracentesis.
It is possible to reposition a capsular IOL if its haptics are made in the form of a closed or open loop. New fixation is carried out by suturing into the groove of the ciliary body. To do this, the IOL must be brought into the anterior chamber and two paracenteses must be performed at 3 and 9 o'clock. A long, thin, straight, atraumatic needle with a 10-0 polypropylene suture made in a loop is passed through one paracentesis into the anterior chamber, passes under the lens and exits through the second paracentesis. To facilitate its passage through the second paracentesis, a thin injection needle should be used as a guide (Fig. 17.14).
Rice. 17.14. The needle passes through paracentesis in the anterior chamber under the IOL
The polypropylene loop is removed from the anterior chamber with a hook over the POL haptic. By passing the needle through the removed loop, you need to get a double loop covering the IOL arch (Fig. 17.15).
Rice. 17.15. The polypropylene drink is pulled out with a microhook through paracentesis over the IOL arch
When the thread is pulled up, the double loop goes through the paracentesis into the anterior chamber.
In the same way, you need to form a double loop on the second IOL arm. After this, opposite the paracenteses, conjunctival flaps are cut out with the base towards the fornix and two blind incisions of the sclera are made radially to the limbus 2.0 mm long on the sclera 1.5 mm from the limbus. A straight needle is reinserted into the anterior chamber through paracentesis. From the opposite side, an injection needle is inserted towards it through one of the notches to remove a straight needle through the sclerotomy (Fig. 17.16).
Rice. 17.16. Forming a loop around the IOL arch
The procedure is repeated on the opposite side. When the polypropylene thread is pulled up on both sides, the IOL unfolds and goes behind the iris (Fig. 17.17).
Rice. 17.17. Passing the needle through paracentesis into the sclerotomy
By passing the needle through the sclera between sclerotomies, you need to form a mattress suture. After tightening the suture knot, it is necessary to conjugate it deep into the scleral tissue to prevent cutting through the conjunctiva.
In cases where repositioning the IOL is not possible, it must be removed. This usually refers to lenses with intracapsular fixation, made in the form of a monolithic block, which dislocate when the posterior capsule ruptures. The easiest way to remove an IOL is through a corneal incision. After the conjunctiva is separated and three sclerotomies are made, an infusion cannula is inserted and sutured, it is necessary to make a non-through incision on the cornea with a length of 6.0-7.0 mm, depending on the size of the IOL. After this, a conventional vitrectomy is performed. The discovered IOL, freed from the CT fibers, is grabbed with vitreal forceps and brought out to the anterior sections of the CT. Here, the IOL is intercepted using a second tweezers inserted instead of the endoilluminator so that it can be easily removed through the pupil and the corneal incision. One forceps is withdrawn and the sclerotomy is closed with a plug. Holding the IOL with tweezers with one hand, the surgeon must puncture the cornea through the previously made incision with the other hand. The infusion is stopped and viscoelastic is injected into the anterior chamber, after which the incision is extended along the notch so that the IOL can be removed through it. Through the pupil, the IOL from the ST is fed into the anterior chamber, and the haptic is directed into the surgical wound (Fig. 17.18).
Rice. 17.18. IOL removal through a corneal incision
Here the IOL must be grasped with tweezers and removed from the eye. The corneal incision should be closed with a running 10-0 monofilament nylon suture. After this, the infusion is turned on and an additional vitrectomy is performed in order to remove all remnants of CT, blood, and fragments of the posterior capsule. If, during the process of removing the IOL, the CT fibers along with the lens came out into the wound and became pinched, they must be removed with a vitreotome.
Repositioning of a dislocated IOL is the ideal way out of this serious complication. The ability to return the IOL to its place and securely fix it entirely depends on the design features of the lens. The IOL suturing after reduction can be done either to the iris or transscleral in cases where the gap is made in the form of a loop. Monolithic lenses made in the form of a plate must be removed.
Article from the book: .
Many problems that arise when implantation of intraocular lenses(IOL), can be effectively eliminated using. Sometimes normally functioning intraocular lenses (IOLs) must be removed to perform vitreoretinal surgery in the posterior segment of the eye. It is important that the implant surgeon is familiar with the basic ways to eliminate problems that arise in the postoperative period of vitreoretinal surgery.
Retrolental intraocular membranes. Most retrolental membranes can be removed using a YAG laser. Membranotomy through the pars plana or translimbal membranotomy (dissection) is rarely indicated. Performing a membranotomy through the pars plana of the ciliary body using vitreoretinal instruments is required in the presence of dense membranes. An infusion tube can be used, but the diameter of the probe must be increased, which reduces access to the membrane. To maintain adequate IOP during surgery, it is best to use a standard infusion cannula.
Membranotomy using scissors, needle or MVR blades performed before membranectomy to create a free margin. Sometimes, in the presence of dense membranes, it is necessary to use scissors to perform their radial segmentation and dissection along the circumference from the ciliary body and iris.
Repositioning of a dislocated intraocular lens (IOL). Implantation of a posterior chamber IOL sometimes ends with its dislocation into the vitreal cavity. In very rare cases, intraocular lens (IOL) positioning and the use of miotics can return the lens to its proper position without surgery. If this method does not lead to the desired result, vitrectomy is required. Surgical manipulation of a dislocated intraocular lens (IOL) without prior vitrectomy causes vitreoretinal traction and should therefore be avoided.
To intraocular lens repositioning(IOL) vitrectomy should be performed using an infusion cannula, a vitreotome, imaging with a contact corneal lens or a wide-angle imaging system, and an endo-illuminator to avoid vitreoretinal traction. The intraocular lens (IOL) is lifted with end-grasping tweezers, and the endo-illuminator is used not only for illumination, but also for additional support of the lens. The lens may be placed in an intact portion of the capsule, ciliary sulcus, or anterior chamber.
Rotation intraocular lens(IOL) in the capsular bag for the defect that caused the dislocation may be effective in some cases. It is possible to place a lens in the ciliary sulcus if the anterior and posterior capsules are fused to each other and provide sufficient support. Some types of intraocular lens (IOL) can be implanted in the anterior chamber if the patient does not have glaucoma or corneal endothelial dystrophy (Fuchs' dystrophy). The shape of the optical surface of the intraocular lens (IOL) is a limiting factor for this technique; it also cannot be used for implantation of silicone lenses. Peripheral iridectomy with a vitreotome should always be performed to prevent pupillary block.
Hemming intraocular lens(IOL) into the groove of the ciliary body through positioning holes was proposed by S. Charles, but this technique is rarely shown and is practically not used at present. Sutures may be placed around the haptic elements of the lens when suturing the intraocular lens (IOL) into the ciliary sulcus. This technique is complex, requires experience and careful planning, and often leads to late postoperative complications such as suture rupture and endophthalmitis.
In some situations IOL can be sutured to the iris using the McCannel technique. To do this, the IOL is grabbed with tweezers and brought out through the pupil into the anterior chamber, while the haptic elements remain under the iris. The introduction of carbachol (Carbacholin) into the anterior chamber leads to pupil constriction and retention of the IOL in this position. If the pupillary sphincter does not function, this greatly complicates the procedure of suturing the IOL to the iris. Once the IOL has been stabilized, viscoelastic is injected into the anterior chamber to push the iris posteriorly and make the outline of the haptic elements visible.
Sutures are placed using a long straight or curved spatula needle with prolene No. 10-0, the needle is inserted through the limbal puncture, passed through the iris, under the haptic element, through the iris on the other side and removed from the eye through the limbus. Paracentesis is not required. Pulling a loop of suture material with a Kuglen hook towards the central paracentesis directly above the haptic element and bringing it out through the limbus allows the surgeon to tie the knot so that, if necessary, it is possible to re-enter the eye cavity and correct the position of the haptic element. This technique can be performed on both haptic elements when the IOL is in full luxation, or on one of them if the opposing element is stable.
