The visual and refractive outcomes of combined and sequential penetrating keratoplasty, cataract extraction, and intraocular lens insertion

Development of a Web-Based Algorithm for Understanding the Intraocular Lens-Based Surgery in Stable and Progressing Keratoconus for Non-Specialist Ophthalmologists

PURPOSE

To propose an algorithm to facilitate lens-based surgery in keratoconus.

METHODS

A literature review was performed to prepare a software algorithm based on cone location, stability, best spectacle-corrected distance visual acuity (BSCVA) level and whether there is a clear or cataractous lens. The software usability was assessed through a 10-question questionnaire and two hypothetical keratoconus case histories (moderately simple and moderately complex) given to 15 trainees. The usability questionnaires were graded on a Likert scale (1 = strongly disagree to 5 = strongly agree) and two case histories (1 = very difficult to 7 = very easy).

RESULTS

The algorithm can be found at https://www.sussexeyelaserclinic.co.uk/keratoconus/. Thirteen trainees completed the questionnaire. 91.9% would frequently use it; for 100%, it was easy to use independently without technical support; for 63.7%, it was strongly integrated; for 100%, it was consistent; 100% thought that most people would learn to use it quickly, 91.9% found the system not cumbersome to use, felt very confident to use it and need not learn a lot to use it. The first case was found easy by 63.7% and the second by 45%.

CONCLUSION

We present an algorithm as a guide for lens-based surgery in stable and progressing keratoconus, which is classified based on cone location. This algorithm will help trainee and "non-specialist" ophthalmic surgeons understand the pre-operative planning for the surgery and referral to the "specialist" corneal surgeon, considering factors such as progression, BSCVA, keratometry, topography and apex location of the cone in keratoconus patients.

Combined versus sequential penetrating keratoplasty and cataract surgery for herpes simplex keratitis: a retrospective study

Purpose

To compare the surgical outcomes of combined penetrating keratoplasty (PK) and cataract surgery with those of sequential surgery (cataract surgery after PK) for herpes simplex keratitis (HSK).

Methods

The medical records of consecutive patients diagnosed with HSK who underwent combined or sequential PK and cataract surgery in active and stable stages between June 2015 and June 2022 were reviewed retrospectively. Complications, graft survival, endothelial cell density (ECD), and final BCVA were compared and analyzed between both surgical methods in each stage.

Results

A total of 171 eyes of 171 patients were enrolled, including active stage (69 combined, 46 sequential) and stable stage (34 combined, 22 sequential). The average follow up was 24.2 ± 15.8 months (range, 3 months - 48 months). The final BCVA had obvious improvement and the postoperative ECD was not different in combined and sequential groups of each stage. In sequential group of active stage, 66.7% of persistent epithelial defects and 50% of HSK recurrence occurred within 3 months after cataract surgery; nevertheless, compared to that in sequential group, capsular rupture (p = 0.021), persistent epithelial defects (p = 0.027), and HSK recurrence (p = 0.035) occurred more frequently in combined group, leading to a lower graft survival rate (p = 0.045); at the last visit, 46.4 and 67.4% of grafts remained clear in combined and sequential groups, respectively. By contrary, 82.4 and 50.0% of grafts remained clear in stable stages of combined and sequential groups at the last visit, respectively, and a higher graft survival rate was observed in combined group (p = 0.030).

Conclusion

Although the postoperative ECD is not different between two surgical groups in each stage, sequential surgery in active stage of HSK seems to have advantages in less complications and higher graft survival rate, whereas combined surgery in stable stage has a better outcome than that in sequential surgery.

Descemet-stripping automated endothelial keratoplasty with intrascleral haptic-fixated intraocular lens in a sequential vs simultaneous approach

PURPOSE

To compare the outcomes of Descemet-stripping automated endothelial keratoplasty (DSAEK) with intrascleral haptic-fixated intraocular lens (IOL) in a sequential and simultaneous approach.

SETTING

Tertiary eyecare center.

DESIGN

Prospective randomized comparative study.

METHODS

Patients with aphakic or complicated pseudophakic bullous keratopathy visiting a tertiary eyecare center were included in the study. A total of 40 patients were randomized into 2 groups of 20 each. Group 1 had subjects who underwent scleral-fixated IOL (SF IOL) implantation by intrascleral haptic fixation technique, followed by DSAEK (sequential procedure) with an interval of at least 3 months. Group 2 (simultaneous) had subjects who underwent DSAEK with SF IOL as a combined procedure. Graft survival, endothelial cell loss (ECL), corrected distance visual acuity (CDVA), and need for any intervention such as rebubbling were evaluated for both the groups at the end of 6 months.

RESULTS

At 6 months, the sequential group had significantly better CDVA of 0.62 ± 0.17 logMAR compared with 0.87 ± 0.19 logMAR in the simultaneous group (P = .002). Group 1 had significantly better overall cumulative graft survival (100% vs 60%, P = .002), significantly lower ECL (P = .006), lesser mean central corneal thickness (P = .03), and significantly thinner donor lenticule (P = .009). Rebubbling rate was significantly higher in Group 2 (P = .025). The mean hyperopic shift was significantly more in Group 2 (P = .02).

CONCLUSION

The sequential procedure of SF IOL followed by DSAEK has better visual outcomes and graft survival when compared with simultaneous procedure in cases of aphakic or complicated pseudophakic bullous keratopathy.

Corneal Pathology and Cataract: Combined Surgery or Sequential Surgery?

Objectives

To compare our combined surgery (CS) and sequential surgery (SS) results.

Materials and Methods

The files of 44 patients who underwent CS (penetrating keratoplasty [PK], cataract extraction, and intraocular lens [IOL] implantation) and 126 patients who underwent SS (cataract extraction and IOL implantation in a second session after PK) between January 2009 and December 2018 were evaluated retrospectively. One eye of the patients who were followed up for at least 1 year was included in the study. The two groups were compared in terms of indications, corrected distance visual acuity (CDVA), refractive results, complications, and graft survival.

Results

In the CS and SS groups, the median age was 63 (30-79) and 43 (18-73) years (p<0.001) and the median follow-up time was 51 (13-152) and 64.5 (13-154) months (p=0.011), respectively. The most common PK indications were traumatic corneal scar (20.5%) and endothelial dystrophy (15.9%) in the CS group versus keratoconus (24.6%) and stroma dystrophy (17.5%) in the SS group. In the CS and SS groups, 50% vs 69% of patients had CDVA ≥0.4 (p=0.04); 45.5% vs 25.4% had CDVA (0.1-0.3) (p=0.04); and 54.5% vs 73% had spherical equivalent ≤±2.0 D (p=0.02). The most common postoperative complications were glaucoma (20.5% vs 15.9%, p=0.48) and allograft reaction (9.1% vs 23%, p=0.04). Graft survival rates were 95.2% vs 86.5% (p=0.10) at 1 year and 75.9% vs 68.9% (p=0.47) at 5 years, respectively.

Conclusion

Over long-term follow-up, the groups were similar in terms of graft survival. For this reason, each patient must be evaluated separately whether to perform a combined or sequential surgery. Given the lower refractive error and higher expectation of final visual acuity, SS can be more advantageous especially in young patients.

Endothelial keratoplasty versus penetrating keratoplasty for Fuchs endothelial dystrophy

BACKGROUND

Fuchs endothelial dystrophy (FED) is a condition in which there is premature degeneration of corneal endothelial cells. When the number of endothelial cells is reduced to a significant degree, fluid begins to accumulate within the cornea. As a result, the cornea loses its transparency and the individual suffers a reduction in vision. The only successful surgical treatment for this condition is replacement of part or all of the cornea with healthy tissue from a donor. The established procedure, penetrating keratoplasty (PKP), has been used for many years and its safety and efficacy are well known. Endothelial keratoplasty (EK) techniques are relatively new surgical procedures and their safety and efficacy relative to PKP are uncertain.

OBJECTIVES

The objective of this review was to compare the benefits and complications related to two surgical methods (EK and PKP) of replacing the diseased endothelial layer of the cornea with a healthy layer in people with FED.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2014, Issue 1), MEDLINE (January 1950 to January 2014), EMBASE (January 1980 to January 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to January 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) and ClinicalTrials.gov (www.clinicaltrials.gov). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 27 January 2014.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing EK versus PKP for people (of any age and gender) who had been clinically diagnosed with FED.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the search results, assessed trial quality and extracted data using the standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

We included three RCTs that enrolled a total of 139 eyes of 136 participants and analysed 123 (88%) eyes. Two RCTs randomised eyes into either the endothelial keratoplasty (EK) group or penetrating keratoplasty (PKP) group and one RCT randomised eyes into either the femtosecond laser-assisted endothelial keratoplasty (FLEK) group or PKP group. The RCTs comparing EK with PKP did not show any significant differences between procedures with respect to best corrected visual acuity (BCVA) at two years (mean difference (MD) 0.14 logMAR; 95% confidence interval (CI) -0.08 to 0.36; P = 0.23) or at one year (MD 0.09 logMAR; 95% CI -0.05 to 0.23; P = 0.22), whereas the trial comparing FLEK with PKP showed significantly better BCVA after PKP (MD 0.20 logMAR; 95% CI 0.10 to 0.30; P = 0.0001). Only one RCT reported on irregular astigmatism (higher-order aberration), which was less with EK than PKP (MD -1.20 µm; 95% CI -1.53 to -0.87; P < 0.001). Only one RCT reported on endothelial cell counts (lower after FLEK than PKP: MD -969 cells/mm²; 95% CI -1161 to -777; P < 0.001), primary graft failure (higher after FLEK than PKP: RR 7.76; 95% CI 0.41 to 145.22; P = 0.10), and graft rejection (more after FLEK than PKP: RR 1.11; 95% CI 0.07 to 17.12; P = 0.94). Only one RCT reported that 27.8% of participants had graft dislocation, 2.8% had epithelial ingrowth and postoperative pupillary block, and 13.9% had intraocular pressure (IOP)-related problems in the FLEK group compared with the PKP group, in whom 10% had suture-related problems, 5% had wound dehiscence and 10% had suture revision to correct astigmatism. Overall, the adverse events in the FLEK group appeared to be more frequent than in the PKP group. No trials reported information about quality of life or economic data. The overall methodological quality of the three trials was not satisfactory as most did not perform allocation concealment or masking of participants and outcome assessors, and all trials had a small sample size.

AUTHORS' CONCLUSIONS

The rapid growth of endothelial keratoplasty as the treatment of choice for FED is based upon the belief that visual recovery is more rapid, surgically induced astigmatism (regular and irregular) is less and rates of transplant rejection are lower with EK. This change in practice also assumes that the rates of long term transplant survival are equal for the two procedures. The practical differences between the surgical procedures mean that visual recovery is inherently more rapid following EK, but this review found no strong evidence from RCTs of any difference in the final visual outcome between EK and PKP for people with FED. This review also found that higher order aberrations are fewer following EK but endothelial cell loss is greater following EK. The RCTs that we included employed different EK techniques, which may have a bearing on these findings. EK procedures have evolved over the years and can be performed using different techniques, for example deep lamellar endothelial keratoplasty, Descemets stripping endothelial keratoplasty (DSEK), Descemets stripping automated endothelial keratoplasty (DSAEK), femtosecond laser-assisted endothelial keratoplasty and Descemet membrane endothelial keratoplasty (DMEK). More RCTs are needed to compare PKP with commonly performed EK procedures such as DSEK, DSAEK and DMEK in order to determine the answers to two key questions, whether there is any difference in the final visual outcome between these techniques and whether there are differences in the rates of graft survival in the long term?

Graft survival and visual outcome after simultaneous penetrating keratoplasty and cataract extraction

AIM

To evaluate the indications, complications, and visual and graft survival outcomes in eyes that had undergone simultaneous cataract extraction and penetrating keratoplasty (PKP).

METHODS

We described a retrospective study of 101 patients who had undergone simultaneous cataract extraction and PKP at King Khaled Eye Specialist Hospital between January 1, 2001, and December 31, 2002. All patients were followed up postoperatively with maximum follow-up 68 months.

RESULTS

The mean age of patients was 61 years. The mean overall follow-up was 27 months. The most common indications for surgery were corneal scarring (45.5%), previous failed graft (15.8%), corneal ulcer (12.9%), Fuchs endothelial dystrophy (8.9%), stromal dystrophy (2.9%), and other conditions (14.5%). Overall, 69 grafts (68.3%) remained clear at final follow-up. Previous glaucoma or postoperative glaucoma had no statistically significant effects on graft outcome (P>0.05).The graft rejection rate (17.8%) was a significant risk factor for failure (P=0.00). Age, gender, indications for surgery, corneal graft diameter, and intraoperative vitreous loss had no statistically significant effects on the PKP outcome (P>0.05). Postoperative visual acuity was significantly associated with preoperative visual acuity (P<0.01).

CONCLUSION

The present study provides evidence that performing a combined procedure results in more rapid visual rehabilitation and good graft clarity.

Comparative cost-effectiveness analysis of descemet stripping automated endothelial keratoplasty versus penetrating keratoplasty in the United States

PURPOSE

To perform a comparative cost-effectiveness analysis of Descemet stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PK) for corneal endothelial disease.

DESIGN

Retrospective cost-effectiveness analysis.

METHODS

This cost-effectiveness analysis was performed from a third-party payer perspective with a 5-year time horizon. Probabilities of outcomes and complications of each of the procedures were calculated based on review of the published literature. A model was constructed to compare the costs and utilities associated with DSAEK and PK. Costs of donor tissue preparation, surgery, follow-up, postoperative complications, and procedures were considered. Utility values were based on quality-adjusted life years associated with visual acuity outcomes. Both costs and utilities were discounted at 3% per year. Sensitivity analyses were performed on key model inputs.

RESULTS

Base case analysis found DSAEK to be less costly compared with PK ($9362 vs $10 239), with greater utility (3.15 vs 2.47 quality-adjusted life years). Sensitivity analyses revealed that even at graft failure rates for DSAEK approaching the rates for PK, DSAEK would still reduce costs. Varying the dislocation rate in our model showed that even at dislocation rates approaching 50%, DSAEK remained less costly. Further, with DSAEK rejection rates as high as 28%, DSAEK would remain a dominant procedure over PK.

CONCLUSIONS

Comparative cost-effectiveness analysis of DSAEK versus PK indicates favorable cost and utility outcomes associated with DSAEK for treatment of corneal endothelial disease. Longer follow-up of DSAEK outcomes will provide more accurate information regarding long-term cost-effectiveness of the procedure.

Descemet membrane endothelial keratoplasty combined with phacoemulsification and intraocular lens implantation: advanced triple procedure

PURPOSE

To evaluate the functional and morphologic outcome of Descemet membrane endothelial keratoplasty (DMEK) combined with phacoemulsification and intraocular lens implantation in patients suffering from endothelial dysfunction and cataract.

DESIGN

Retrospective, single-center, consecutive case series.

METHODS

Triple-DMEK (DMEK with simultaneous cataract surgery) was performed in 61 consecutive eyes of 56 patients using corneal donor tissue pre-stored in either short-term culture (Optisol-GS) at 4 C or organ culture (Dulbecco's modified Eagle's medium, CorneaMax medium) at 34 C. Main outcome measures included the number of air injections necessary for graft attachment as well as best-corrected visual acuity (BCVA [logMAR]), central corneal thickness (CCT), endothelial cell density (ECD), refractive spherical equivalent, refractive cylinder, and topographic cylinder at 1, 3, and 6 months postoperatively.

RESULTS

BCVA increased from 0.6 ± 0.23 logMAR preoperatively (n = 54) to 0.19 ± 0.22 logMAR at 6 months (n = 27) after surgery (P ≤ .05). ECD of donor corneas decreased from 2573 ± 235 cells/mm(2) (n = 61) to 1550 ± 326 cells/mm(2) (n = 29) after 6 months (P ≤ .05). CCT decreased from 651 ± 69 μm (n = 54) preoperatively to 521 ± 65 μm (n = 27) after 6 months (P ≤ .05). Refractive spherical equivalent was -0.3 ± 2.8 D (n = 27) preoperatively and 0.9 ± 1.5 D 6 months (n = 27) after surgery. A total of 54.5% of eyes were within 1 D of emmetropia (n = 12) and 77.3% were within 2 D of emmetropia (n = 17) 6 months (n = 22) after surgery. Refractive cylinder was -0.9 ± 1.0 D preoperatively (n = 49) and -1.5 ± 1.0 D 6 months (n = 23) after surgery. The change in refractive cylinder within the first month was statistically significant (P ≤ .05; Wilcoxon test). Topographic cylinder was 2.1 ± 1.7 D preoperatively (n = 58) and 1.7 ± 1.1 D 6 months (n = 28) after surgery. Between 3 and 6 months a significant change in topographic cylinder towards lower values was measured (P ≤ 0.05; Wilcoxon test). Optimized spherical results were achieved by selecting intraocular lenses based on a hyperopic shift of -0.75 D.

CONCLUSION

DMEK combined with cataract surgery (triple procedure) can routinely be performed in cases of endothelial dystrophy and cataract. The addition of cataract surgery to DMEK had no adverse effect on endothelial function or graft adhesion and did not increase the likelihood of postoperative complications.

Endothelial keratoplasty versus penetrating keratoplasty for Fuchs endothelial dystrophy

BACKGROUND

Fuchs endothelial dystrophy (FED), first described by Ernst Fuchsis in 1910, is a condition in which there is premature degeneration of corneal endothelial cells. When the number of endothelial cells is reduced to a significant degree fluid begins to accumulate within the cornea. As a result the cornea loses its transparency and the individual suffers a reduction in vision. The only successful surgical treatment for this condition is replacement of part or all of the cornea with healthy tissue from a cadaveric donor. The established procedure, penetrating keratoplasty (PKP), has been used for many years and its safety and efficacy are well known. Endothelial keratoplasty (EK) is a relatively new surgical procedure and the safety and efficacy relative to PKP are unknown.

OBJECTIVES

The objective of this review is to collate information on the benefits and complications related to two surgical methods (PKP and EK) of replacing the diseased endothelial layer of the cornea with a healthy layer in people with FED.

SEARCH STRATEGY

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 2), MEDLINE (January 1950 to February 2011), EMBASE (January 1980 to February 2011), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to February 2011), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) and ClinicalTrials.gov (www.clinicaltrials.gov). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 6 February 2011.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing EK versus PKP for people (of any age and gender) who had been clinically diagnosed with FED. When assessing the primary and secondary outcome measures, only RCTs were included in the analysis. As per our protocol a description of data from non-randomised comparative studies is also reported. As RCTs may not detect differences in frequency of adverse events, when assessing these we included data from cohort studies with more than 50 participants and a follow-up of up to five years.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

The electronic searches identified one RCT, five non-randomised comparative studies and 34 cohort studies with a sample size of over 50 participants for inclusion. The RCT was conducted in the USA and included 28 eyes of 25 participants with FED. Although this is a very good RCT, there may be potential for bias due to lack of masking of assessors and possible selective reporting not being clearly reported. In this RCT, comparing EK versus PKP, best corrected visual acuity (BCVA) was similar at 24 months (PKP 0.20 ± 0.20 logMAR; EK 0.34 ± 0.35 logMAR; P = 0.23) and higher order aberrations (HOAs) (deviations of the performance of an optical system from the predictions of paraxial optics) were lower with EK. No other data were reported by the trial. Based on data obtained from both non-randomised comparative studies and individual cohort studies the endothelial rejection rate was between 5.3% and 23.2% for PKP and 2% and 4% for EK. However the mean follow-up duration in the EK cohort studies was noticeably shorter. The rate of EK graft dislocation requiring repositioning ranged from 3% to 63%, with the majority of studies having a rate of < 10%.

AUTHORS' CONCLUSIONS

There is no high quality evidence that EK is superior to PKP in the treatment of FED considering the studies that satisfied our primary and secondary outcome measures. One RCT demonstrated that HOAs are lower following EK and some lower quality evidence suggests that endothelial rejection episodes may be less with EK. These findings should be interpreted with caution as they are based on data with risk of biases. Further RCTs of visual and refractive outcomes needs to be performed in this field, comparing EK to PKP, with a larger sample size and at least five years of follow up. To avoid bias due to a surgeon's learning curve, procedures should be performed by experienced surgeons only. Quality of life and vision should also be evaluated. The risk of endothelial rejection will be difficult to address in the context of a RCT because of power considerations but large non-randomised comparative case series and corneal graft registry outcome data will be useful in this regard.

Simultaneous phacoemulsification and graft refractive surgery in penetrating keratoplasty eyes

Purpose. To report outcomes of graft refractive surgery (GRS) along with clear-cornea phacoemulsification and intraocular lens (IOL) implantation in penetrating keratoplasty (PKP) eyes. Methods. Fourteen eyes of 13 patients who had received PKP underwent simultaneous GRS (relaxing incisions with or without counter-quadrant compression sutures) and clear-cornea phacoemulsification with IOL implantation. To calculate IOL power, preoperative keratometry readings and the SRK-T formula were used. Results. Mean patient age and follow-up period were 50.5 ± 14.4 years and 14.6 ± 7.1 months, respectively. A significant increase was observed in best spectacle-corrected visual acuity (from 0.55 ± 0.18 logMAR to 0.33 ± 0.18 logMAR, P = 0.001). There was a significant decrease in vector keratometric astigmatism by 6.22 D (P = 0.03). Spherical equivalent refraction was reduced from −3.31 ± 3.96 D to −1.69 ± 2.38 D (P = 0.02) which did not significantly differ from the target refraction (−0.76 ± 0.14 D, P = 0.20). No complications developed and all the grafts remained clear at the final examination. Conclusion. Simultaneous phacoemulsification and GRS is a safe and effective method to address post-PKP astigmatism and lens opacity. IOL power can be calculated from preoperative keratometry readings with an acceptable accuracy. However, patients should be informed about the possibility of high refractive errors postoperatively.