Traditional Penetrating Keratoplasty Research Articles

Review of clinical trials addressing the Boston Keratoprosthesis

ObjectiveThe Boston Keratoprosthesis (KPro) has gained recognition as an alternative for patients with severe corneal disease and a poor probability of success with traditional penetrating keratoplasty. This review summarizes the knowledge clinical trials have brought to KPro and discusses ongoing trials. DesignSystematic review. MethodsA literature review across PubMed, Ovid MEDLINE, Cochrane CENTRAL, and ClinicalTrials.gov was performed to identify relevant published clinical trials reporting on the KPro from all years up until September 2021. All published trials were included. ResultsThere are 6 published and 6 ongoing clinical trials studying the Boston KPro. The number of patients included per trial ranged from 8 to 37. The average age of patients included per trial ranged from 39 to 62 years. Patients were followed for an average of 36.3 ± 41.8 months. Fifty percent (3 of 6) of KPro clinical trials were randomized. Indication for KPro was reported in 67% of trials (4 of 6), with primary KPro accounting for 22% of unique eyes (13 of 58) and KPro after corneal graft failure accounting for 41% of unique eyes (24 of 58), when reported. Using version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2) to assess quality and risk of bias, 50% of trials (3 of 6) had a low risk of bias, 33% (2 of 6) had some bias concerns, and 17% (1 of 6) had a high risk of bias. ConclusionsThere are few clinical trials published and underway on the Boston KPro, and none directly compare KPro outcomes with repeat corneal transplantation. There is a need for long-term clinical trials on the KPro to provide quality evidence for clinical decision making.

Graft rejection in component keratoplasty.

Among the various indications for keratoplasty, failed graft is one of the commonest indications in many published series. It is well known that the major cause of graft failure is endothelial rejection. In the last two decades, there has been a major paradigm shift in the surgical management of corneal diseases, and component keratoplasty has emerged from the concept of replacing the layer that is actually diseased, rather than replacing the full-thickness cornea with the traditional penetrating keratoplasty. This has resulted in improved outcomes and the risk of endothelial rejection has reduced drastically, thus expanding the survival time of the graft. In recent years, reports of graft rejection in component keratoplasty have emerged, with each having a different presentation and responding to a different line of treatment. This review aims to summarize the presentation, diagnosis, and management of graft rejections in component keratoplasty.

Demography, indications and outcome of descemet stripping automated endothelial keratoplasty in Nepal.

Descemet stripping automated endothelial keratoplasty (DSAEK) is performed for corneal endothelial pathology. It had gained popularity over penetrating keratoplasty (PK) because of better outcome. Retrospective data was collected from records of patients who underwent DSAEK from 2005 to 2019. Demography, indications and post-operative complications of DSAEK were analyzed. Outcome was measured in terms of graft clarity and vision. 93 eyes of 86 patients had undergone DSAEK in the study period of 15 years. Average age of the patients was 61.0 years. 55.9% were female. The common indications for DSAEK were cataract surgery related bullous keratopathy (n=47, 50.5%), Fuchs dystrophy (n=22, 23.6%) and failed graft (n=11, 11.8%). 8.6% of surgeries had graft detachment and 5.3% had pupillary block in the early post-operative period. Outcome analysis was done for cases (n=80) which had follow-up duration of at least 2 months (range: 2 months to 11 years; average: 28.5 months).Endothelial rejection occurred in 8 cases (10.0%), 5 of which regained graft clarity after treatment. At the last follow-up visit, 23.8% (n=19) of grafts had failed, which was mostly due to endothelial failure (n=16); 3 grafts failed due to infective keratitis. 42.5% (n=34) acquired best corrected vision of 6/18 or better. The average astigmatic error was 1.6 Diopter Cylinder by refraction. DSAEK showed good outcome with our results comparable to other studies. It had replaced traditional PK in our institute for endothelial dysfunction. Surgeons in the country should be encouraged and trained to do the procedure.

Evolving Techniques and Indications of Descemet Membrane Endothelial Keratoplasty.

Endothelial keratoplasty has replaced traditional penetrating keratoplasty for the treatment of corneal endothelial dysfunction. It offers faster, more predictable, stable visual recovery and low rejection rates while the surgery itself is less invasive. Descemet membrane endothelial keratoplasty (DMEK) is currently the gold standard for the treatment of Fuchs endothelial dystrophy, bullous keratopathy, and corneal edema after cataract surgery. Its favorable long-term outcomes are increasingly reported by large study groups. This review summarizes the current literature on new DMEK techniques, including size and shape modifications, new graft delivery techniques, and surgical pearls for challenging cases like eyes with glaucoma, glaucoma tubes, and failed penetrating keratoplasties.

Individualized Corneal Patching for Treatment of Corneal Trauma Combined with Tissue Defects.

Aim To evaluate the efficacy of individualized corneal patching using a minimal graft for corneal trauma combined with tissue defects. Methods Fifteen eyes (15 patients) were enrolled in this study, including 8 eyes with corneal perforation induced by removal of metal foreign bodies, 5 eyes with corneal laceration resulting from metal trauma, and 2 eyes with pencil injuries to the cornea. The size, shape, and depth of the tissue defects were assessed. For corneal perforation or irregular tissue defects, if the diameter or length was ≥3.0 mm, traditional penetrating keratoplasty (PK) or lamellar keratoplasty (LK) was adopted; if the diameter or length was ＜3.0 mm, a conical or irregular patch consistent with the defects was used. The visual acuity, corneal status, and postoperative complications were observed during the follow-up. Results The diameter of corneal perforations was 1.0 mm in 2 eyes, 1.5 mm in 1 eye, 2.0 mm in 4 eyes, and 3.5 mm in 1 eye. During their PK procedures, a conical corneal graft was used in 7 eyes, while a traditional cylindrical graft was used in 1 eye. The other 7 eyes had corneal trauma combined with irregular tissue defects, which were full-thickness corneal defects in 5 eyes and lamellar defects in 2 eyes, all less than 3.0 mm in length. Thus, five eyes received PK, and 2 eyes received LK using an irregular wedge-shaped patch. The visual acuity increased greatly postoperatively, with mild corneal astigmatism. None of the patients developed immune rejection. Conclusion Individualized corneal patching with a minimal graft can save corneal materials, relieve corneal scars, gain a good visual prognosis, and avoid immune rejection in the treatment of corneal trauma combined with tissue defects.

The Boston keratoprosthesis

The Boston Keratoprosthesis (KPro) is one of several types of artificial cornea manufactured worldwide that are being implanted in increasing numbers in patients with severe corneal diseases and graft failures. To summerize the advances in design of the Boston type I keratoprosthesis and in the treatment strategies to conquer the post operative complications have expanded the indications and application of this technology. Many modifications to the design of the Boston type I keratoprosthesis and treatment of the patient in the post operative period have occurred. Also, the technology has been more widely accepted as a primary surgical option for patients with a poor preoperative prognosis for traditional penetrating keratoplasty. The outcomes of visual acuity, retention, and post-operative infection rates have all significantly improved since the technology has been modified and offers patients an alternative for visual rehabilitation. This is implanted into a carrier corneal graft or into the patient's own cornea. The allograft cornea can be the carrier, which may solve the shortage of donor cornea in China.

Boston Type 1 Keratoprosthesis: Updated Perspectives.

The use of Boston type 1 keratoprosthesis (BKPro) has significantly increased worldwide. It is no longer considered a procedure of last resort but a reasonable option for patients with otherwise poor prognosis for a traditional penetrating keratoplasty. BKPro was approved by the Food and Drug Administration in 1992 for bilateral severe corneal blindness due to multiple corneal transplant failure. Over the years, indications have extended beyond recurrent immunologic rejection to include other conditions such as chemical injury and other causes of bilateral limbal stem cell deficiency, extensive corneal neovascularization, neurotrophic corneas and hypotony, among others. Numerous advances in the design of the BKPro, improvement of preoperative, intraoperative and postoperative management have resulted in favorable outcomes and a reduction in postoperative complications. Accordingly, many studies have shown that implantation of this device is highly effective in restoring vision with very good short-term outcomes. However, due to the lifetime risk of sight-threatening complications after BKPro implantation, a longer follow-up period should provide outcomes that are more realistic. In this review, the authors examined only the results of publications with an average of at least 2 years of follow-up. The overall intermediate to long-term visual outcomes and retention rate in BKPro seem to be favorable. However, autoimmune diseases and cicatrizing conditions continue to show a higher incidence of postoperative complications that require further management.

Is There a Cutoff in Favor of Penetrating Keratoplasty Rather than Endothelial Keratoplasty for Long-Standing Endothelial Decompensation?

Endothelial keratoplasty (EK) has evolved to become the standard of care over traditional penetrating keratoplasty (PK) for treating isolated corneal endothelial disease. EK provides numerous advantages including faster, more reliable visual rehabilitation, along with a lower allograft rejection rate. There are some situations, however, in which EK may not necessarily be the best option, and PK should at least be considered. In such situations, a careful weighing and balancing needs to be done in conjunction with the patient.

Five year outcomes of Boston type I keratoprosthesis as primary versus secondary penetrating corneal procedure in a matched case control study.

Despite improved retention and reduced complication rates paving the way for the current expansion of applications and surge in prevalence for the Boston type I Keratoprosthesis (KPro), the most frequent indication for its implantation today remains prior graft failure. The purpose of this study is to evaluate the long-term outcomes of primary KPro and compare to secondary implantation in a matched cohort study. This study included patients who underwent KPro implantation in a single center by two surgeons between July 2008 and October 2014. All eyes with KPro implantation as the primary procedure with a minimum follow up of 12 months were matched with eyes with same preoperative diagnoses that underwent secondary KPro implantation. Main outcomes included visual acuity and device retention. A total of 56 eyes were included with 28 eyes in each group. Mean follow up was 5.0 years for both groups. Twenty-nine percent (8) of the eyes in the primary group had a diagnosis of chemical or thermal injuries, 25% (7) aniridia, 18% (5) autoimmune disease, 4% (1) infectious keratitis/neurotrophic cornea, 7% (2) gelatinous corneal dystrophy, 7% (2) ectrodactyly ectodermal dysplasia/limbal stem cell deficiency, and 11% (3) uveitis/hypotony. Sixty-one percent (17) of the eyes in the primary group and 39% (11) in the secondary group maintained a final best-corrected visual acuity of 20/200 or better at a mean follow up of 5.0 years; the probability of maintaining best-corrected vision is 0.83 and 0.49 for primary and secondary groups at 5.0 years (p = 0.02). There is no statistically significant difference between groups in device retention (p = 0.22) or postoperative complication rates (p >0.05). This study demonstrates that Boston KPro implantation may be successful as a primary procedure in patients at high risk of failure with traditional penetrating keratoplasty. The device has a good long-term retention rate and visual outcomes are promising however a larger study is needed for more definitive results.

Allogeneic sclera graft combined autologous conjunctival flap for repairing the emergent corneal perforation

To report a palliative and alternative surgical procedure, allogeneic sclera graft combined with autologous conjunctival flap (ASGACF), employing to repair the large emergent corneal perforation. The detail protocol of the surgical procedure was characterized and four representative cases were reviewed. An allogeneic sclera graft and recipient bed were prepared as the traditional penetrating keratoplasty (PK). And then sutured the sclera graft to the bed with 10-0 nylon suture and covered with a pedicled autologous conjunctival flap in half size. In the follow-up, the ASGACF repaired all of the corneal perforations and restored the integral walls of eyeballs, in spite of one who underwent a second surgery. This surgical procedure provided a palliative method to repair the large emergent corneal perforation while there is the lack of a corneal graft.

Boston Keratoprosthesis Type 1 in the Pediatric Population

Purpose of Review Pediatric corneal blindness is a worldwide problem that is very difficult to address. Traditional penetrating keratoplasty is considered a high-risk procedure in this population due to the host of complications that are often encountered. Even when anatomic success is achieved with penetrating keratoplasty, visual recovery is not guaranteed.

Type 1 Boston keratoprosthesis: outcomes at two Canadian centres

ObjectivesTo report the outcomes of patients who underwent Boston type 1 keratoprosthesis (Kpro) surgery at the University Health Network (Toronto, Ont.) and the University of Ottawa Eye Institute (Ottawa, Ont.) between June 2008 and July 2013. DesignRetrospective case series. ParticipantsForty-four eyes of 43 patients who underwent Kpro surgery. MethodsA retrospective review was conducted of all Kpro procedures performed by 4 attending cornea surgeons. The preoperative characteristics and postoperative course of each patient were analyzed. ResultsIn 31 eyes (70%), the primary indication for a Kpro was failed corneal transplantation. The remaining 13 eyes (30%) had Kpro as a primary procedure. In all eyes, preoperative visual acuity (VA) was 20/150 or worse, with 39 eyes (89%) having a VA of counting fingers, hand movement, or light perception. Mean follow-up time was 21 ± 12 months (range 12–57 months). The retention rate at the last follow-up was 95%. Best-achieved median VA was 20/100 (range 20/20 to no light perception [NLP]), with 37% of patients achieving a VA of >20/40 at some point during their postoperative course. At the last follow-up, median VA was 20/400 (range 20/30 to NLP). The 2 most common complications included retroprosthetic membrane formation (23 eyes, 52%) and elevated intraocular pressure (10 eyes, 23%). There were 5 cases (11%) of stromal melt and 1 case (2%) of infective keratitis. ConclusionsThis study demonstrates that Kpro improves VA in a majority of cases, and is a viable option in situations in which there is a poor prognosis for traditional penetrating keratoplasty.

Simultaneous penetrating keratoplasty and artificial iris‐lens diaphragm implantation

AbstractMaterials and methods: Forty four eyes of 44 patients with aniridia after penetrating corneal injuries and traumatic post radial keratotomy wound dehiscences have undergone penetrating keratoplasty (PKP) and simultaneous artificial iris‐lens diaphragm (ILD) implantation. The average age was 36 years (8‐60 years). Time since trauma ranged from 3 months to 17 years. In 27 eyes intraocular pressure (IOP) was normal preoperatively, while 17 eyes were diagnosed with glaucoma. IOP was managed medically in 9 of these eyes, and 8 eyes had been operated for glaucoma before PKP + ILD. PKP was performed with the assistance of femtosecond laser in 10 eyes, and 34 eyes were operated with the use of Barron vacuum trephine. Five eyes had previous successful retinal detachment surgery, and 8 eyes had subtotal vitrectomy for vitreous hemorrhage. Results: Preoperatively mean non‐corrected distance visual acuity (NCDVA) was 0.03 ± 0.04 (m ± SD), corrected distance visual acuity (CDVA) was 0.04 ± 0.07, preoperative corneal astigmatism was 8.3 ± 5.8 diopters (D). Twelve months after the surgery mean NCDVA after traditional PKP was 0.08 ± 0.09, CDVA was 0.2 ± 0.19, corneal astigmatism was 4.7±3.9 D; and after femtolaser‐assisted PKP NCDVA was 0.1 ± 0.12, CDVA 0.3 ± 0.28, corneal astigmatism was 3.9 ± 3.1 D. In the group of 8 eyes previously operated for glaucoma only 1 eye experienced worsening of IOP control, requiring 2 extra filtering procedures including drainage device implantation. In the glaucoma medical management group of 9 eyes 1 eye required filtering surgery 1 month after PKP + ILD, while four more had to be operated for glaucoma as late as 9 to 24 months. Due to transplant failure cornea had to be regrafted in 6 of 9 patients in the glaucoma medical management group, and only in 2 of 8 patients who were previously operated for glaucoma. Conclusion: In patients after simultaneous penetrating keratoplasty and artificial iris‐lens diaphragm implantation surgery corneal transplant failure rate increases with IOP decompensation. Previous glaucoma surgery improves IOP control.

Corneal Allograft Rejection: Immunopathogenesis to Therapeutics

Corneal transplantation is among the most successful solid organ transplants. However, despite low rejection rates of grafts in the ‘low-risk’ setting, rejection can be as high as 70% when grafted into ‘high-risk’ recipient beds. Under normal homeostatic conditions, the avascular cornea provides a unique environment that facilitates immune and angiogenic privilege. An imbalance in pro-inflammatory, angiogenic and lymphangiogenic mediators leads to a breakdown in corneal immune privilege with a consequent host response against the donor graft. Recent developments in lamellar and endothelial keratoplasties have reduced the rates of graft rejection even more, while providing improved visual outcomes. The corneal layer against which an immune response is initiated, largely determines reversibility of the acute episode. While epithelial and stromal graft rejection may be treated with topical corticosteroids with higher success, acute endothelial rejection mandates a more aggressive approach to therapy due to the lack of regenerative capacity of this layer. However, current immunosuppressive regimens come with the caveat of ocular and systemic side effects, making prolonged aggressive treatment undesirable. With the advent of biologics, efficacious therapies with a superior side effect profile are on the horizon. In our review we discuss the mediators of ocular immune privilege, the roles of cellular and molecular immune players in graft rejection, with a focus on human leukocyte antigen and antigen presenting cells. Furthermore, we discuss the clinical risk factors for graft rejection and compare rates of rejection in lamellar and endothelial keratoplasties to traditional penetrating keratoplasty. Lastly, we present the current and upcoming measures of therapeutic strategies to manage and treat graft rejection, including an overview of biologics and small molecule therapy.

Ceratoprótese de Boston

A short review of type 1 Dohlman-DoaneKeratoprosthesis (KPro) addresses results and complications. Dohlman-DoaneKPro is today a good option for cases of corneal blindness with poor prognosis for traditional penetrating keratoplasty. KPro design and surgical improvements along with proper preoperative ocular surface condition allows good results in non-immune diseases. Main complications of this KPro areinflammatory retroprosthetic membrane, glaucoma, corneal melting,vitreitis, and infection (keratitis and endophthalmitis). Comprehensive long-term postoperative follow-up examinationsare needed to monitor for and prevent serious complications.

Cost-Effectiveness of Descemet's Stripping Endothelial Keratoplasty versus Penetrating Keratoplasty

Selective endothelial transplantation in the form of Descemet's stripping endothelial keratoplasty (DSEK) is rapidly replacing traditional full-thickness penetrating keratoplasty (PK) for endothelial disease. An incremental cost-effectiveness analysis was performed to determine whether the benefits of DSEK are worth the additional costs. Retrospective cohort study. Patients at the Singapore National Eye Center, a tertiary eye center in Singapore, with Fuchs' dystrophy or bullous keratopathy who underwent either PK or DSEK. Patients underwent either PK (n = 171) or DSEK (n = 93) from January 2001 through December 2007. Data were collected from inpatient and outpatient notes corresponding to the time immediately before the procedure to up to 3 years after. Improvements in best spectacle-corrected visual acuity were used to calculate the increase in quality-adjusted life years (QALYs) 3 years after the procedure. This was combined with hospital charges (a proxy for costs) to determine incremental cost-effectiveness ratios (ICERs) comparing PK with no intervention and DSEK with PK. Three-year charges for DSEK and PK were $7476 and $7236, respectively. The regression-adjusted improvement in visual acuity for PK relative to no intervention was -0.613 logarithm of the minimum angle of resolution (logMAR) units (P<0.001), and for DSEK relative to PK, it was -0.199 logMAR units (P = 0.045). The regression-adjusted marginal gain in utility for PK relative to no intervention was 0.128 QALYs (P<0.001) and for DSEK relative to PK was 0.046 QALYs (P = 0.031). This resulted in ICERs of $56 409 per QALY for PK relative to no intervention and $5209 per QALY for the more expensive DSEK relative to PK. If the goal is to maximize societal health gains given fixed resources, DSEK should be the preferred strategy. For a fixed budget, it is possible to achieve greater QALY gains by providing DSEK to as many patients as possible (and nothing to others), rather than providing PK.

Expanding Application of the Boston Type I Keratoprosthesis Due to Advances in Design and Improved Post-operative Therapeutic Strategies

Purpose: To evaluate how the advances in design of the Boston type I keratoprosthesis and in the treatment strategies to conquer the post operative complications have expanded the indications and application of this technology.Methods: A review and analysis of the keratoprosthesis literature specifically examining design modifications, treatment of post operative complications, and patient selection was performed.Results: Over the past two decades, many modifications to the design of the Boston type I keratoprosthesis and treatment of the patient in the post operative period have occurred. Also, the technology has been more widely accepted as a primary surgical option for patients with a poor preoperative prognosis for traditional penetrating keratoplasty. The outcomes of visual acuity, retention, and post-operative infection rates have all significantly improved since the technology has been modified and offers patients an alternative for visual rehabilitation.Conclusions: Thanks to advances in design and perioperative care, the boston type i keratoprosthesis can now be considered a viable option for surgical visual rehabilitation in many patients with corneal pathology, and in certain groups the primary surgical procedure of choice.

Descemet's Stripping Endothelial Keratoplasty: An Effective Treatment for Toxic Anterior Segment Syndrome with Histopathologic Findings

To report Descemet's stripping endothelial keratoplasty (DSEK) as a treatment for corneal edema associated with toxic anterior segment syndrome. A 75-year-old woman presented with decreased vision in her left eye after uneventful phacoemulsification. She was diagnosed with toxic anterior segment syndrome and a DSEK was performed. Histologic sections were examined after staining with hematoxylin and eosin, periodic acid Schiff, and Masson trichrome; immunoperoxidase reactions were used to identify cytokeratins, vimentin, and alpha-smooth muscle actin. The corneal endothelium was selectively replaced by the DSEK technique. Descemet's membrane and endothelium were stripped from the recipient's stroma, and an 8-mm-diameter donor button consisting of posterior stroma and healthy endothelium was folded and implanted through a 5-mm incision. An air bubble was used to press the donor tissue against the recipient cornea, allowing it to attach without sutures. Corneal edema and visual acuity improved. Histopathologic evaluation of the DSEK specimen disclosed a multilaminar retro-Descemet's fibrous membrane in which many of the constituent fibroblasts contained scattered pigment granules and stained for both vimentin and cytokeratin with immunoperoxidase methods. To the best of our knowledge, this is the first reported case of successful DSEK in a patient with corneal decompensation resulting from toxic anterior segment syndrome exhibiting a retrocorneal fibrous membrane. Visual recovery was rapid, and refractive changes were minimal compared with traditional penetrating keratoplasty. The immunoperoxidase staining strongly suggests that the retrocorneal fibrous membrane was created by dysplastic corneal endothelial cells.

Fungal Endophthalmitis After Descemet Stripping Automated Endothelial Keratoplasty-A Case Report

Descemet stripping automated endothelial keratoplasty (DSAEK) is increasingly gaining popularity as an effective alternative to traditional penetrating keratoplasty for the treatment of endothelial diseases. However, new complications such as donor graft dislocation are seen after DSAEK. Surface venting incisions have been advocated to reduce rates of graft dislocation. We report a case of post-DSAEK fungal endophthalmitis in which the clinical course may have been influenced by the presence of surface venting incisions. A retrospective case report. A 72-year-old woman, who developed primary/iatrogenic graft failure after DSAEK, underwent a repeat DSAEK. Corneal venting incisions were reopened at the original sites as her first operation. Early postoperatively, she developed intrastromal opacities, which were thought to be epithelial downgrowth, but progression and increasing stromal and intraocular inflammation required anterior chamber and vitreous tap, which confirmed the presence of Candida parapsilosis, confirming the diagnosis of fungal endophthalmitis. Penetrating keratoplasty, removal of the posterior lamellar graft, removal of the posterior chamber intraocular lens implant (PCIOL) and capsular bag, and anterior vitrectomy were performed after failure of conservative antifungal therapy. Postoperatively, no recurrence of infection occurred, and the graft has remained clear at her most recent follow-up at 6 months, with a best-corrected visual acuity of 20/40. Corneal venting incisions in DSAEK surgery may be a portal of entry for microorganisms, leading to corneal and intraocular infection, and a high index of suspicion is warranted in the presence of stromal infiltrates or inflammation at venting sites.

Corneal Sensation After Descemet Stripping and Automated Endothelial Keratoplasty

To measure corneal sensation after Descemet stripping and automated endothelial keratoplasty (DSAEK). Prospective comparative case series involving 52 eyes of 29 patients in the early postoperative period (<6 months) after small-incision DSAEK. Patients' contralateral eye served as a control. The sample size calculation was calculated assuming an alpha error of 0.05 and a beta error of 0.2. This determined that a sample size of 11 patients would be sufficient to detect a difference in corneal sensation of 5 mm as measured with the Cochet-Bonnet esthesiometer. The nylon filament was used to measure threshold sensation at 9 points on the operative eye and 5 points on the control. The data were analyzed using the paired samples test. Although the results demonstrated mild hypesthesia of the corneal epithelium overlying the donor lenticule, we found no statistically significant difference in corneal sensation at the central point when comparing the DSAEK cornea with the control (57 vs 59 mm, P = 0.13.) In addition, when comparing corresponding points on the epithelium overlying the DSAEK graft and host cornea, no significant difference was found (57 vs 58 mm, P = 0.32). A difference was detected when comparing the average corneal sensation of the DSAEK eye with the control, but careful analysis of the data shows that this was driven by the slight decrease in sensitivity at the temporal incisional point (57 vs 59 mm, P = 0.002). The results of this prospective study demonstrate the relative preservation of corneal sensitivity after DSAEK. Preservation of corneal sensation may provide another advantage of DSAEK over traditional penetrating keratoplasty.