IOL suture fixation after penetrating corneal transplantation
Observational Analysis of Ocular Visual Acuity
Wang Hongge Dong Xiaoguang Tian Jingyi
【Abstract
Objective To analyze the visual acuity and astigmatism of IOL suture fixation with CZ70BD in penetrating corneal transplantation eyes after IOL suture fixation.
The purpose of this study is to analyze the visual acuity and astigmatism of penetrating corneal transplantation eyes with CZ70BD IOL suture fixation, and to discuss methods to improve the visual acuity and visual quality after surgery. Wang Hongge, Ophthalmology Department
Methods A retrospective analysis was performed on patients who underwent CZ70BD IOL suture fixation after penetrating corneal transplantation in our hospital, and the visual acuity and astigmatism before and after surgery were compared.
Results Postoperative visual acuity was significantly better than preoperative, and postoperative astigmatism increased compared to preoperative.
Conclusion Suture fixation of CZ70BD-type IOL can significantly improve the visual acuity of lens-free eyes after penetrating corneal transplantation, and resolving postoperative astigmatism is the key to improving visual quality.
【Key words】 Penetrating keratoplasty, IOL suture fixation, visual acuity, astigmatism
After corneal transplantation, patients with cloudy corneal optics combined with lens capsule loss due to trauma and surgery still have poor vision due to the absence of the lens. IOL suture fixation can improve the vision of some of these patients. Among the patients who underwent IOL suture fixation in our hospital, some of them had undergone penetrating corneal transplantation before surgery. We analyzed the pre- and post-operative visual acuity of these patients to find out the factors affecting their post-operative visual acuity and to discuss ways to improve the visual quality of these patients.
Materials and methods
1. Data: Between February 2004 and April 2005, 35 patients with 35 eyes, 24 males and 11 females, aged 7 to 79 years old, with an average of 33.0 years old, underwent second-stage IOL suture fixation in our hospital more than 6 months after penetrating corneal transplantation. Among them, 4 eyes were treated with anterior chamber IOL and penetrating corneal transplantation after anterior chamber IOL removal due to corneal endothelial dysfunction, and 31 eyes were treated with traumatic cataract extraction and penetrating corneal transplantation after ocular trauma; 29 of the 35 eyes had undergone total vitrectomy before IOL suture fixation.
2. Methods: All selected patients had preoperative best corrected visual acuity ≥ 0.1. Eye axis and corneal curvature were examined, and if corneal curvature could not be detected in the operated eye, the curvature of the contralateral eye was referred to, corneal endothelial count was ≥ 1000/mm2, and routine fundus examination combined with ultrasound and UBM was performed to exclude posterior retinopathy and anterior proliferative vitreoretinal lesions. The SRK-T formula was used to calculate the degree of the implanted lens. The IOL A constant was 118.8. For patients who had undergone vitrectomy, intraocular irrigation was established at the scleral orifice 3.5 mm behind the inferior temporal scleral rim to maintain stable intraocular pressure, and the locator was coated with sterile blue dye to mark a clear position at the corneal rim. The position of the clock point was marked on the corneal limbus with sterile blue dye, and a 7-mm-long lamellar scleral port was made 3 mm posterior to the upper corneoscleral limbus to implant the CZ70BD lens in a 3-point and 9-point horizontal position, and the two loops of the IOL were fixed with sutures 1.5 mm posterior to the corneoscleral limbus. Naked visual acuity and corrected visual acuity were examined 3 months after surgery and the results were recorded.
Results
1. Pre- and post-operative visual acuity: preoperatively, all patients had bare eye visual acuity ranging from index M10CM to 0.2, 12 eyes (34.29%) with visual acuity
The postoperative astigmatism ranged from 0.00-7.00 DC, with a mean of 2.09 DC and a mean spherical lens of 9.48 DS. The postoperative astigmatism ranged from 0.5-7.0 DC, with a mean of 2.7 DC and a mean spherical lens of 2.34 DS. The postoperative astigmatism was greater than the preoperative astigmatism, and the postoperative spherical lens was smaller than the preoperative astigmatism. The differences were statistically significant (P < 0.05).
Discussion
Achieving better visual acuity and good visual quality in aphakic patients by various methods is a goal pursued by clinicians, and IOL suture fixation has become an important method to improve visual acuity in aphakic eyes due to various causes [1, 2]. Most patients with aphakic eyes have poor visual acuity, and if the patient also has a corneal transplant, the astigmatism caused by the suture of the corneal implant may make the visual acuity even worse, with 82.86% of our patients having naked eye visual acuity ≤0.1 and only 17.14% having naked eye visual acuity ≥0.1, thus most patients need surgery or lens correction to obtain useful visual acuity. These patients cannot undergo conventional IOL implantation because they do not have the support of lens capsule. Fixing the IOL in the ciliary sulcus through sutures to improve the vision of the affected eye and obtain binocular vision is currently the best option for these patients. In this group of patients, 17.14% had preoperative visual acuity > 0.1, while 94.29% had postoperative visual acuity > 0.1 (P < 0.001). The significant improvement of postoperative visual acuity compared with preoperative visual acuity is also a favorable proof of the effect of IOL suture fixation surgery.
The visual acuity of patients after penetrating corneal transplantation is affected by various factors, such as the transparency of the corneal implant, the degree of corneal astigmatism, the condition of the lens, and the condition of the fundus and optic nerve. The IOL suture fixation after penetrating corneal transplantation, in addition to the routine operation, special attention should be paid to the protection of the corneal implant [3], because most patients have a low number of corneal implant endothelium, and measures to protect the corneal endothelium are used such as injecting the appropriate amount of viscoelastic Viscoat into the anterior chamber, using BSS-Plus as the perfusion solution, gentle surgical operation, and trying not to deform the cornea. In addition, the control of astigmatism during surgery is more difficult because the sutures of corneal implants sometimes cause irregular astigmatism.
The preoperative astigmatism was 0.00-7.00 DC, mean 2.09 DC, and mean spherical lens 9.48 DS. The postoperative astigmatism was 0.5-7.0 DC, mean 2.7 DC, and mean spherical lens 2.34 DS. Although the postoperative spherical lens was significantly lower than the preoperative one (P < 0.001), the postoperative astigmatism was greater than the preoperative one, and the difference was statistically significant (P < 0.05). The difference was statistically significant (P < 0.05). It can be seen that although the visual acuity improved, the visual quality of the patients still had problems, and the patients did not feel significantly better after surgery compared with their preoperative visual acuity.
The astigmatism of the patient was greater before surgery, with an average of 2.09 DC, and the postoperative astigmatism was more severe than before surgery, with an average of 2.7 DC. The surgery did not reduce the astigmatism overall, but increased it, indicating that the surgery itself caused a new astigmatism. The reason is that the CZ70BD suspension IOL is a non-folding rigid lens and must be implanted through an incision of at least 7 mm in length, and the result of such a length of incision suture is bound to be astigmatism. . To both improve visual acuity and quality of vision, the problem of astigmatism must be addressed. This is a problem that is difficult to overcome with large incision surgery and is a major drawback of the CZ70BD suspension type rigid IOL, only the magnitude of the astigmatism varies. Many patients have large astigmatism before surgery, and it would be more ideal if the surgery could not reduce the original astigmatism, but at least not increase it further, or even reduce part of the astigmatism that existed before surgery.
The best way to solve post-operative astigmatism should be to prevent astigmatism from the root, reduce the incision of the implanted IOL, and avoid new astigmatism when closing the surgical incision to the maximum extent possible. The reduction in incision length and the resulting postoperative visual acuity results favorably support the feasibility of this approach as proposed by the authors, as cataract surgery shifts from extracapsular lens extraction to lens ultrasound emulsification. Encouraging results have been achieved by surgeons who have used sutureless corneal incisions with second-stage IOLs fixed with double-loop sutures in the absence of corneal lesions to treat lens-free capsular eyes [4]. Thus, for aphakic capsular eyes after penetrating corneal transplantation has been performed, the traditional method of implanting a rigid IOL through a large transscleral incision can be discarded in favor of small incision implantation of a folded IOL with suture fixation to further improve the visual acuity and visual quality of patients with aphakic capsular supported IOLs after penetrating corneal transplantation. This has not been reported in China yet, and it needs to be tried and summarized by fellow ophthalmologists in their future clinical work to accumulate valuable clinical experience.
References.
1．Shi Tian Yan Liang Dan Phase I vitrectomy and Phase II folding IOL suture loop fixation for traumatic total lens dislocation, Chinese Journal of Trauma, 2004, 10: 624
2. Zheng Guangying, Zhang Xiangmei, Penetrating corneal graft IOL suture fixation for complex penetrating eye injuries, Chinese Journal of Practical Ophthalmology, 2000, 11: 698
3. Dong Xiaoguang, Xie Lixin, Hu Longji, Evaluation of IOL implantation on corneal endothelial injury, Chinese Journal of Ophthalmology, 1993, 29: 346
4. Yu Jinqiang, Zhong Xiaodong, Second-stage IOL double-loop fixation without sutured corneal incision, Chinese Medical Series, 2004, 4: 53
Visual Acuity Evaluating of Secondary Trans-scleral Fixation of Posterior Chamber Intraocular Ienses After Penetrating Keratoplasty
WANG Hongge DONG Xiaoguang TIAN Jingyi
Shandong Eye Hospital, Jinan,Shandong Province PRC 250021
ABSTRACTS
Objective: To analyze the astigmatism and visual acuity of Trans-scleral Fixation of Posterior Chamber Intraocular Ienses (PCIOL CZ70BD) after penetrating keratoplasty, find a way to improve the visual acuity and vision quality.
Methods: Review the data of patients who performed Trans-scleral Fixation of Posterior Chamber Intraocular Ienses (PCIOL CZ70BD) after penetrating keratoplasty, and compare the astigmatism and visual acuity before and after the Trans-scleral Fixation of Posterior Chamber Intraocular Ienses (PCIOL CZ70BD).
Results: visual acuity after fixation of IOL improved significantly (P < 0.001) and astigmatism increased after fixation of PCIOL (P < 0.05).
Conclusions: Trans-scleral Fixation of Posterior Chamber Intraocular Iens (PCIOL CZ70BD) after penetrating keratoplasty improved visual acuity Significantly, the key to improve the visual quality is to reduce or eliminate astigmatism caused by the operation itself.
【key words】 penetrating keratoplasty Trans-scleral Fixation of Posterior Chamber Intraocular Ienses (PCIOL) visual acuity astigmatism