Objective: To observe the clinical efficacy of retinal detachment surgery under surgical microscope combined with indirect fundoscopy.
Methods: In 46 cases (46 eyes) with foraminal retinal detachment, the localization of the fissure and condensation were done under the surgical microscope, and the fundus was examined by indirect ophthalmoscopy after the external pressure was applied to understand the relationship between the pressure ridge and the fissure.
Results: The retinal lacunae and condensation reaction were clearly visible under the direct view of the surgical microscope, and the position of the silicone block was adjusted by indirect ophthalmoscopy in 12 cases. In 43 eyes (93.5%), the retina was completely repositioned in one operation; the final visual acuity improved in 35 eyes, remained unchanged in 8 eyes, and decreased in 3 eyes.
Conclusion: Scleral buckling under the surgical microscope is simple and convenient for fissure condensation and localization; the combined use of indirect fundoscopy to check the relationship between the pressure ridge and the fissure intraoperatively makes the position of the pressure ridge more accurate and reliable.
Retinal detachment of aperture origin is a common blinding eye disease, and the principle of treatment for it is to close the foramen. Scleral buckling, as a routine procedure for retinal detachment, has a high surgical success rate for the majority of early-onset lacunar-derived retinal detachments. The traditional surgical method is to locate and condense the lacunae under indirect fundoscopy, and to complete these operations such as external pressure, ring ligation and drainage of subretinal fluid under the naked eye, which is relatively not delicate enough, and the fundus image seen by the indirect ophthalmoscope is inverted, with small magnification and long learning curve.
The microscopic scleral buckling procedure developed in recent years is performed under the surgical microscope, which is a detailed, convenient and easy to master operation, but it is difficult to observe the relationship between the pressure ridge and the lacunae under the microscope because of the inconvenience of pressure on the top of the eye after suturing the extra scleral pressure block.
Since 2006, we have been using an operating microscope in combination with an indirect ophthalmoscope to perform external retinal detachment surgery, i.e., all surgical steps, including the localization of the lacunae and condensation, are performed under the operating microscope, and the relationship between the lacunae and the pressure ridge is observed under the indirect ophthalmoscope after surgery, and the pressure ridge is adjusted according to the observation results. The surgical results were satisfactory and are reported as follows.
1. Subjects and methods
1.1 Subjects
The patients were 46 eyes of 46 cases of retinal detachment of lacunar origin treated in our department from November 2006 to November 2007, with postoperative follow-up of more than 3 months. Age ranged from 15 to 77 (average 45) years, with 21 eyes on the right and 25 eyes on the left. The extent of retinal detachment ranged from limited to total detachment, including 6 eyes with total detachment, 4 eyes with near total detachment, 37 eyes with retinal detachment involving the macula, and 2 eyes with vitreous hemorrhage. Retinal round holes were found in 22 eyes, horseshoe holes in 26 eyes, jagged edge detachment in 3 eyes, multiple lacunae in 19 eyes, and no clear lacunae were found in 2 eyes. 38 eyes had PVR grade A, 5 eyes had grade B, 3 eyes had grade C, and 4 eyes had choroidal detachment.
Before surgery, the fundus was routinely examined by slit lamp combined with anterior microscopy and indirect fundoscopy, and the exact site of the lacunae was finally determined by triangulation. The scope of retinal detachment, the morphology, size, number and location of the fissures, and the P V R classification were recorded in detail, and the fundus map was drawn. Preoperatively, antibiotic eye drops were routinely applied, and the pupil was dilated daily with Medrol-P eye solution.
1.2 Methods
All patients were operated under local anesthesia, and the bulbar conjunctiva was cut along the corneal limbus under the operating microscope. Depending on the surgical approach, the entire bulbar conjunctiva was cut or cut in one quadrant, and the fascial sac was opened between the two rectus muscles with scissors and the bulbar fascia was bluntly separated.
After cold needle puncture to discharge subretinal fluid and/or anterior chamber puncture to soften the eye, the operator uses the light source of the operating microscope to illuminate the eye, and with one hand, the operator uses the toothed forceps to lift the extraocular muscle to fix the eye and adjust the position of the eye, and with the other hand, the freezing head is held on the surface of the sclera corresponding to the retinal fissure and pressed toward the center of the eye. The freezing is stopped when the retina around the fissure is white, and the same treatment can be done for the retina in the degenerative area.
Ligation of the preset pressure block sutures, with ring ties shortened by about 10 mm, and observation of the height and width of the pressure ridge and its relationship with the retinal lacunae through the indirect inspection lens, with the lacunae in the front slope of the pressure ridge as the satisfactory position, unsatisfactory then adjust the position of the pressure block until satisfactory. If the IOP is too low or the fissure is in the shape of a fish mouth, SF6 gas is injected from 4 mm after the corneal rim to increase the IOP or flatten the fissure.
2. Results
2.1 Intraoperative situation
All patients underwent smooth surgical procedures, including 42 cases with segmental external pressure pads, radiolucent or circular external pressure depending on the status of the lacunae, fixed with one to three pairs of scleral mattress sutures, including three cases with two pressure blocks. 4 cases underwent circular ligation combined with silicone external pressure due to high PVR or multiple lacunae in multiple quadrants. Subretinal fluid was drained in 42 cases, and anterior chamber puncture was applied in 7 cases, including 3 cases in which anterior chamber puncture was applied in combination with fluid release due to inadequate softening of the eye by retinal drainage alone. In the two cases in which no fissure was detected preoperatively, the fissure was found after adequate lowering of IOP and careful parietal pressure on the peripheral retinal area. The position of the pressure ridge was checked by indirect ophthalmoscopy during surgery, and the position of the silicone block was adjusted in 12 cases because the pressure ridge was found to be anterior or posterior. No complications such as accidental scleral and retinal penetration and intraocular hemorrhage occurred during the surgery.
2.2 Post-operative situation
The follow-up period was from 3 months to 1 year. The retina was completely reset in 43 eyes (93.5%) in one operation, and there were three cases of recurrence, two of which recurred due to missed fissure and were reset by reapplication of external pressure, and the other case had retinal reset after switching to vitrectomy due to aggravation of PVR. a small subretinal slice of subretinal hemorrhage was found after surgery in one case, and all of them were absorbed after 3 weeks. a macular fissure occurred in one and a half months after surgery, but the retina was flattened and the patient chose conservative The patient chose conservative treatment. One case with several proliferating subretinal striae was well repositioned except for traction shallow detachment at the striae that remained. The final visual acuity improved in 35 eyes, remained unchanged in 8 eyes, and decreased in 3 eyes.
3.Discussion
External retinal detachment surgery is to cause inward scleral indentation in the wall of the eye to relieve vitreous traction, parietal pressure on the fissure, and to permanently close the retinal fissure by condensing the retinal pigment epithelium and neuroepithelium to produce a local inflammatory adhesion response. The traditional surgical method is to locate and condense the fissure under an indirect fundoscope, which has a small magnification and is not easy to identify the tiny fissure; the imaging is inverted, which is difficult for beginners to master; it is often necessary to repeatedly take it off and put it on during the operation, which is inconvenient and will increase the chance of infection; these operations, such as external pressure, ring ligation and drainage of subretinal fluid, are done under the naked eye, which is relatively not delicate enough and prone to complications such as scleral perforation and suture avulsion.
In this study, the microscopic scleral exenteration has been developed in recent years, and all surgical steps, including lacunae positioning and condensation, are performed under the operating microscope, with the following advantages.
①The microscopic operation is more delicate and accurate than the naked eye operation, and it causes less damage to the ocular tissues, so that the technical advantages of the ophthalmologist are brought into play. For example, the depth and span of the scleral suture can be easily observed and grasped, and the choroidal hemorrhage and retinal impaction can be reduced by careful observation when releasing fluid.
②After releasing the fluid, the intraocular pressure is reduced, and the condition of the fissure and the surrounding area of the retina can be clearly seen under the microscope with high and adjustable magnification and positive image, which has a three-dimensional sense and can distinguish the subtle lesions of the retina.
③Under direct vision, the retinal fissure can be accurately located and the condensation reaction can be observed, avoiding repeated condensation, insufficient condensation or excessive condensation.
④The whole circumference of the fundus can be observed by parietal pressure without changing the operator’s position, and the assistant can observe and cooperate with the operation at the same time, which simplifies the operation, provides a clear view, shortens the operation time, and reduces the chance of infection.
⑤ Compared with the traditional indirect ophthalmoscopy surgery, its operation is simple and easy to master, and the learning curve is short, which improves the efficiency of the surgery.
Because the position of the preset pressure block is inferred from the calculation of preoperative examination, it is crucial to check the relationship between the fissure and the pressure crest before the end of surgery in order to clarify the status of the fissure apex pressure. Microscopic retinal detachment surgery has shortcomings in this regard.
①After ligating the prepositioned scleral pressure suture, the intraocular pressure rises significantly and the pressure block is not easily and adequately indented, which is not easy to observe under the microscope. If further fluid release or anterior chamber puncture reduces the intraocular pressure then the intraocular pressure is too low after surgery, and it may be necessary to inject gas or water to raise the intraocular pressure, thus increasing the occurrence of complications;
②The pressure on the pressure block with forceps may change the relationship between the pressure ridge and the fissure because of the different forceps holding site or the direction of pressure, which may lead to an incorrect judgment. Therefore, we use the indirect inspection lens to observe the relationship between the fissure and the pressurized ridge, which does not require pressure on the pressurized block, and the relationship between the in situ fissure and the pressurized ridge is observed, and the position of the pressurized block can be adjusted to ensure that the fissure is on the anterior slope of the pressurized ridge.
Although the magnification of the indirect inspection lens is small and the image is inverted, it is still relatively easy to grasp as long as we observe the relationship between the known fissure and the pressurized ridge without observing too many details. In our study, the position of the silicone block was adjusted in 19 cases because the pressure ridge was found to be anterior or posterior by indirect ophthalmoscopy, and the postoperative observation was satisfactory in all cases.
Although the drainage of subretinal fluid is controversial, most surgeons believe that the release of fluid facilitates the visualization and localization of the lacunae and retinal repositioning, and choose to release fluid when needed. Another important role of fluid release in this procedure is to soften the eye, and only when the eye is sufficiently softened can the retina be pressed up via the scleral apex so that it can be seen directly under the microscope.
In this study, the cold needle was chosen to directly puncture and release the fluid, and the site was chosen to safely enter the subretinal cavity, avoiding thick vortex vein branches, and the sclera and choroid were punctured vertically with a disposable 1 ml syringe needle at about 12 mm after the corneal limbus at the proposed fluid release site, and the needle was withdrawn when there was fluid outflow. The subretinal fluid can be discharged if the retina can be seen directly under the microscope after the pressure on the eye, and it is not required to completely discharge the subretinal fluid to avoid low intraocular pressure.
In this group, a small amount of subretinal hemorrhage was found in one case after surgery, which might be caused by the injury to the choroidal vessels during fluid release, but no retinal penetration, retinal embedding and other fluid release related complications were observed. Compared with the traditional fluid release method, this method has similar success rate and fewer complications in a single release, and there is no risk of retinal embedding because of the small puncture opening, and the operation is simpler. For patients with shallow retinal detachment that is not suitable for fluid release, 0.1-0.3 ml of atrial fluid is released by anterior chamber puncture with a disposable 1 ml syringe needle to soften the eye and can be repeated.