RU2276596C1 - Method for removing liquid perfluororganic substance as single drop from under retina after vitreoretinal operation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: method involves puncturing retina in highest drop position in transpupillary way with YAG-laser beam. Then, the patient is placed in prone position for 2 h. Delimiting retina laser coagulation operation is carried out in transpupillary way at the second day after retinal puncture operation. Coagulates are placed beginning from retina detachment boundary and then along laser-made hole boundary.

EFFECT: avoided surgical intervention; reduced risk of traumatic complications.

Description

The invention relates to medicine, more specifically to ophthalmology, and can be used in the treatment of retinal detachment using plugging substances, namely liquid perfluororganic compounds (PFOS).

The use of liquid organofluorine compounds significantly increased the effectiveness of retinal detachment (OS) surgery. However, their use is associated with a number of complications, one of which is the ingress of liquid PFOS, in the form of a separate drop, into the subretinal space, i.e. under the retina during the introduction of PFOS into the vitreous cavity. The occurrence of this complication is most likely during surgery of retinal detachment, complicated by giant retinal ruptures and a pronounced degree of proliferative vitreoretinopathy, it is in such situations that PFOS can flow through the edge of the rupture under the retina. This problem is described in a number of foreign sources (for example, Lee G.A., Finnegan S.J., Bourke R. D. Subretinal perfluorodecalin toxicity // Aust. N.Z. J. Ophthalmol. - 1998. - Vol.26. - No. 1. - P.57-60). The surgeons of our Center also faced this problem. At the end of the vitreoretinal operation, using plugging substances, PFOS is replaced with a gas and a drop of PFOS, if it gets under the retina during PFOS injection, it is flattened by the tamping force of the gas bubble and is not visualized by the surgeon during the operation, but is detected only after gas resorption, those. in the postoperative period. Leaving a drop of PFOS under the retina is not safe. So PFOS, in the form of a drop, has a negative effect on the retinal pigment epithelium, causing atrophy of the epithelium and, as a result, the appearance of scotoma. By Lee G.A. et al. (1998) presented a case of PFOS localization under the retina in the macula; as a result, the development of retinal pigment epithelium in this atrophy zone was observed. Toxic destruction of the retina was also noted in a study by Berglin L. et al. (1993) in the eyes of rabbits. The localization of PFOS under the retina is also dangerous because PFOS, in the form of a drop, is able to move under the retina. Especially dangerous are its movements towards the macula.

A known method of removing PFOS, located in the form of a single drop, from under the retina surgically: repeated surgical intervention (Escalada GF, Mateo GC Extraction of subfoveal liquid perfluorocarbon // Arch. Soc. Esp. Oftalmol. - 2002. - Vol.77. - No. 9. - P.519-521 - PROTOTYPE). Those. 3 scleral incisions are again required to introduce instruments into the vitreous cavity, then the retina in the area of the projection of the drop, at the point of its greatest distance (in practice, this is the center of the drop) is coagulated with a diathermocoagulator and punctured in the coagulation area with a retinal peak. Liquid PFOS is passively aspirated using a cannula on the backflush handle. Then the puncture site of the retina is delimited by endolaser coagulation.

The disadvantages of the method:

1) repeated surgical intervention is required, which in some patients causes a negative reaction, and sometimes undesirable according to general indications (severe somatic pathology, advanced age, single eye, etc.);

2) there is a risk of intraoperative complications;

3) restrictive laser coagulation, performed right there during the operation, may not be effective enough, because the retina does not have time to straighten and lie down.

There is a method where the retina is punctured, under which there is fluid, not surgically, but with the help of a YAG laser beam directed transpupillary (i.e. through the pupil) to the fundus - this technology was developed in our Center (PATENT of the Russian Federation No. 2090169 - analogue). However, this technology is intended to treat transudative maculopathies. This method allows you to puncture the retina in the projection zone of the transudate (punctured in the lower or temporal zone, 1-3 pulses, power 6-8 mJ), followed by leakage of the transudate into the vitreous cavity. However, this technology does not allow to obtain the technical result to which the invention is directed: to remove a drop of PFOS from under the retina. The reason is that these two liquids (transudate and PFOS) have different physical characteristics (density, surface tension, viscosity), and also occupy a different area: PFOS - small, in the form of a small drop (0.5-1.5 the area of the optic disc), and transudate can occupy a significant area of the macula. The large transudate area allows the laser surgeon to choose the puncture site and most often this is the lower zone. When liquid PFOS falls under the retina in the form of a drop (the object is very small), in order to puncture the retina in the area of the projection of the drop, the surgeon in practice focuses the laser beam in the center of the drop in order to obtain a guaranteed result in one approach.

When creating the invention, the technical task was to remove a drop of PFOS from under the retina without surgical intervention, which would reduce the morbidity and eliminate the risk of surgical and postoperative complications.

This is achieved if, in the method of removing liquid perfluororganic compound, in the form of a separate drop, from under the retina by puncture of the retina at the point of highest drop retention followed by laser-coagulation of the retinal puncture site, the puncture should be performed transpupillary with a YAG laser, and then lay the patient face down for 2 hours, and restrictive laser coagulation should be performed transpupillary on the 2nd day after retinal puncture, and coagulates must first be applied along the border of the retinal detachment, and then the edge of the hole.

Among the essential features characterizing the method, the distinguishing ones are:

- the retina is punctured transpupillarly (through the pupil) by the beam of a YAG laser;

- after the puncture, the patient is laid face down for 2 hours;

- laser coagulation is performed transpupillary on the 2nd day after retinal puncture;

- coagulates are applied first along the border of the retinal detachment caused by the drop of PFOS, and then along the edge of the hole made by the laser beam.

Between the totality of the essential features and the claimed technical result, there is a causal relationship.

The retina is punctured in the projection zone of the PFOS drop using a YAG laser beam (we partially use the well-known technology developed at our Center - RF patent No. 2090169). The puncture point, as in the prototype (surgical puncture method), is the point of the droplet's highest standing, which guarantees an atraumatic and reliable opening of the object - PFOS drop (the drop is small in area and the beam is focused more reliably in the center of this drop). If the patient is not placed face down after the puncture, then due to the high density of liquid PFOS (2 times more than the transudate), it will not rush into the hole made in the center of the detached retina, because the force vector will be directed downward, and not toward the hole. With the patient facing down, a drop of PFOS flows into the vitreal cavity. Moreover, as practice has shown, 2 hours are enough for leakage. PFOS flows out in a single drop and at the same time leaves a channel in the retina, expanding towards the vitreous cavity (show optical sections obtained by performing optical coherence tomography of this zone). This is not observed with the YAG laser retinopuncture of the transudative cavity in the macula (PATENT of the Russian Federation No. 2090169 - analogue), because the transudate is less dense, has a lower surface tension and flows out in a trickle, and not in the form of a drop. There is no expanding channel in the case of the prototype, although they also work with liquid PFOS, but there is passive aspiration of PFOS in the patient's supine position. Having received a funnel-shaped channel in the claimed invention with laser retinopuncture, the diameter of which increased (in comparison with the initial laser beam) due to the drop of PFOS, the retina is given time, if possible, to occupy its anatomical position, and only on the second day a laser is cut off coagulation. It is possible to let the retina straighten and lie down only with this technology, because Distinctive laser coagulation is carried out through the pupil (the eyes are not opened), and if there was a need to perform it even later, it would also be possible. In the case of the prototype (surgical method of retinal puncture), restrictive coagulation is carried out immediately after retinal puncture, because diathermocoagulation is used (a coagulation tool is inserted into the vitreous cavity and the retina coagulates immediately after puncture), while the retina is unable to lie naturally, because no time is allotted for this.

Due to the fact that in the claimed invention, entering the vitreous cavity, the drop of PFOS creates an expanding channel, then the laser-coagulation must be performed first along the boundary of the detachment, i.e. each coagulate is placed half where the retina is not peeled, and the other half where it was peeled, but two days after the puncture, the retina managed to lie down (peripheral zone). This coagulation enhances the positive effect of the next stage of coagulation: the second row of coagulates is applied during the same session along the edge of the hole (this is the expanded part of the channel), thereby, using the laser beam, the retina is pulled into the center of the exfoliated zone, narrowing the puncture hole as much as possible .

As a result of the combination of the above actions, it is possible to remove a drop of PFOS from under the retina, while ensuring a reliable fit of the retina in this area, and the patient does without repeated surgical intervention. A small amount of PFOS in the CT cavity is not dangerous and does not reduce the visual function of the eye, this is confirmed by foreign sources of information and our practice.

Thus, between the set of essential features and the claimed technical solution, there is a causal relationship.

The method is as follows.

On the eye, in which PFOS is detected under the retina, in the form of a drop, maximum mydriasis is achieved and epibulbar anesthesia is performed. Then the patient is seated in front of the YAG laser, a universal three-mirror Goldman lens is installed on the eye. The aiming beam of the YAG laser focuses on the point of the highest distance of the PFOS drop (this is the center of the drop) and puncture of the detached retina is performed. Laser radiation parameters: wavelength - 1064 nm, number of pulses - 1, power 2-4 mJ (depends on the transparency of the media). After a retinal puncture, the patient is placed face down for 2 hours. A drop of PFOS enters the ST cavity during this time, and on the second day after the puncture, when the retina lies on the periphery of the detachment, it is precisely along the detachment border (around the circumference) that laser coagulates are applied transpillary. Then (second row), retinal coagulation is performed along the edge of the hole (as close to it as possible). By using this action with the help of coagulates and precisely along the edge of the hole, and not at a distance from it, it is possible to obtain the maximum possible contraction of the hole through which a drop of PFOS comes out, which has significant surface tension and specific gravity and stretches the hole. If this manipulation is not performed, the hole in the retina will remain relatively large, and this is unacceptable. Parameters of laser coagulation: wavelength - 532 nm, energy - 100 mW, pulse duration 50 ms, coagulum diameter - 50 μm, number of pulses - 15. The results of optical coherence tomography showed that the retina was completely snug in the area where the PFOS drop was located before, occurred on day 7 (the completion date for the formation of coagulates).

Example.

A 26-year-old patient was admitted to the hospital with a diagnosis of subtotal retinal detachment, complicated by a large retinal rupture at 11 o’clock, PVR C2, right eye artifact. The visual acuity of the right eye was 0.05 sph-3.5 D = 0.25.

The patient underwent a 3-port vitrectomy using PFOS perfluorooctane, after retinal adaptation, endolaser coagulation was performed and PFOS was replaced with 20% C4F8 gas.

After 2 weeks, the visual acuity of the operated eye was 0.05 sph-4.0 D = 0.4, Po = 16.5 mm Hg. An ophthalmoscopy revealed a drop of PFOS in the upper paramacular region. An additional study using optical coherence tomography confirmed the presence of retinal neuroepithelial detachment with a diameter of 1500 μm and a height of about 1 mm. Computer perimetry showed the presence of paracentral scotoma and decreased retinal sensitivity, respectively, of the pathological focus.

The next day, the patient was punctured by a detached retina using a YAG laser beam. Radiation parameters: wavelength 1064 nm, the number of pulses - 1, E = 2.4 mJ. After retinal puncture, the patient was placed face down for 2 hours. On the second day after the puncture, differential laser coagulation was performed, first the coagulates were applied along the border of the retinal detachment, and then along the edge of the hole. Optical coherence tomography performed daily showed that on the 7th day the retina was fully snug.

During the observation period of up to 3 months, the parameters of visual acuity and the anatomical state of the retina remained stable. Computer perimetry showed the absence of scotomas. Visual acuity 0.15 sph-4.0 D = 0.5, Po = 23 mm Hg

The use of liquid PFOS is a prerequisite for high-quality surgery of retinal detachment. However, in some cases, the use of PFOS is accompanied by the ingress of its individual drops under the retina, which, when exchanged for gas, go unnoticed and are detected only in the postoperative period. The problem of eliminating PFOS, in the form of a drop, from under the retina can be successfully solved using a non-invasive method - YAG laser puncturing of the retina in the area of localization of the PFOS drop, with the patient then facing down to exit the droplet into the ST cavity and restrictive laser coagulation, performed on the 2nd day after puncture: first along the border of the retinal detachment, and then along the edge of the hole.

In our Center, 3 patients were treated who, in the postoperative period, after replacing PFOS with gas, PFOS was detected under the retina in the form of a drop. In all three cases, a drop of PFOS was successfully removed from under the retina using the inventive technology. The danger from the drop of PFOS to the visual functions of the eye was eliminated in time.

Claims (1)

A method for removing a single drop of liquid perfluororganic compound from under the retina after surgery for retinal detachment by puncture of the retina at the point of highest drop retention followed by laser-coagulation with a punctuation site, characterized in that the retina is punctured with a transpupillary YAG laser beam, after which the patient is laid face down for 2 hours, and restrictive laser coagulation is performed transpupillary on the second day after retinal puncture, and coagulates are applied first along the border of the detachment etchatki and then along the edge of the hole.