Advantages of Double Running Sutures in Astigmatism After Penetrating Keratoplasty

Background

Methods

Results

Conclusion

Update on Suture Techniques in Corneal Transplantation: A Systematic Review

Effective suturing remains key to achieving successful outcomes in corneal surgery, especially anterior lamellar keratoplasty and full thickness transplantation. Limitations in the technique may result in complications such as wound leak, infection, or high astigmatism post corneal graft. By using a systematic approach, this study reviews articles and conducts content analysis based on update 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria). The aim of this paper is to summarize the state of the art of corneal suturing techniques for every type of corneal transplant and patient age and also their outcomes regarding astigmatism and complications. Future developments for corneal transplantation will be also discussed. This is important because especially the young surgeon must have knowledge of the implications of every suture performed in order to achieve consistent and predictable post-operative outcomes and also be aware of all the possible complications.

Post-penetrating keratoplasty astigmatism

Postoperative astigmatism is one of the common complications affecting visual outcomes after a penetrating keratoplasty. It can result from various factors related to host, donor and surgical technique, resulting in suboptimal visual outcome. While some of the measures taken during preoperative planning and during actual surgery can reduce the magnitude of postoperative astigmatism, postoperative correction of astigmatism is often required in cases with high degrees of astigmatism. When spectacles and contact lenses fail to provide optimal visual outcomes, various surgical techniques that include astigmatic keratotomy, compression sutures, toric intraocular lens placement, and laser refractive procedures can be considered. When none of these techniques are able to achieve a desired result with in the acceptable optical range, a repeat keratoplasty is considered a last option. We discuss the various causes and management of complication of postoperative astigmatism occurring after a full thickness corneal transplantation surgery.

The effect of different suturing techniques on astigmatism after penetrating keratoplasty

The purpose of this study was to compare the effects on astigmatism after penetrating keratoplasty with three different suture techniques. In this prospective study, 38 eyes of 38 patients underwent penetrating keratoplasty with three suturing techniques: interrupted, single running, and double running. Topographic astigmatism was measured at 2, 6, 12, and 18 months after keratoplasty. During 18 months after surgery, the interrupted suture group had higher astigmatism than the double running suture group. There was no significant difference in the amounts of astigmatism during the first year after keratoplasty between the single running and the double running suture group. However, at 18 months after surgery, when all sutures were out, the double running suture group (3.60+/-1.58 diopters) showed significantly less astigmatism than the single running group (5.65+/-1.61 diopters). In conclusion, post-keratoplasty astigmatism was the least in the double running suture group of the three suturing techniques at 18 months after penetrating keratoplasty.

Iris-sutured posterior chamber intraocular lens implantation during penetrating keratoplasty

PURPOSE

To evaluate the clinical indications and postoperative results of iris-sutured posterior chamber intraocular lens implants performed during penetrating keratoplasty.

METHODS

Medical records were retrospectively reviewed for preoperative indications and postoperative results of 342 consecutive patients (366 eyes) who underwent iris suturing of a posterior chamber intraocular lens implant during penetrating keratoplasty over a 9-year period.

RESULTS

Mean follow-up was 36 months. The principal indications for corneal transplantation were pseudophakic and aphakic bullous keratopathy. Mean postoperative best spectacle-corrected visual acuity was better than preoperatively at all measured time points (P < 0.0001) and improved from 20/474 preoperatively to 20/85 at 1 year. Nine eyes (7.7%) with known preoperative glaucoma required escalation of therapy by medication or surgery to control the intraocular pressure. Seventy-two eyes (29%) without known preoperative glaucoma required treatment of elevated intraocular pressure. Seventy-nine eyes (28%) without known preoperative cystoid macular edema were additionally diagnosed. Mean endothelial cell counts declined throughout the study time frame. Corneal donor rejection episodes occurred in 36 (9.8%) eyes, with the majority having a single episode. Overall, 27 (7.4%) eyes had known graft failure at last follow-up. Two eyes (0.5%) were enucleated following wound disruption.

CONCLUSIONS

These long-term results of iris-sutured posterior chamber intraocular lens implants performed during penetrating keratoplasty suggest acceptable visual acuity, graft survival, and complication rates. They are similar to published retrospective and prospective results of flexible open-loop anterior chamber and transsclerally-sutured posterior chamber intraocular lens implants placed during penetrating keratoplasty.

Keratometric astigmatism after suture removal in penetrating keratoplasty: double running versus single running suture techniques

BACKGROUND AND OBJECTIVE

To compare astigmatism after suture removal in a retrospective sequential series of patients who had penetrating keratoplasty with either a double running suture technique or an adjustable single running suture technique. During the first year postkeratoplasty, when sutures were in place, the latter technique had produced less astigmatism.

MATERIALS AND METHODS

Keratometry and keratometric astigmatism were measured before and after suture removal. We compared these variables in 30 grafts with the double running suture technique to the same variables in 24 grafts with the single running suture technique.

RESULTS

The final portion of the double running suture was removed 408 +/- 177 (mean +/- SD) days after keratoplasty, whereas the single running suture was removed 611 +/- 224 days after keratoplasty (P<0.001). After suture removal, there was no difference between the double running and single running groups in either mean keratometry [46.5 +/- 1.8 diopters (D) versus 45.6 +/- 2.0 D, P=0.09, minimum detectable difference (MDD)=1.5D] or mean astigmatism (4.6 +/- 2.7 D versus 5.2 +/- 3.2D, P=0.72, MDD=2.3).

CONCLUSION

In this consecutive series of corneal transplants performed by one surgeon, the results suggest no difference in astigmatism between the two suturing techniques after all sutures have been removed.