Cases Of Keratoplasty Research Articles

A retrospective analysis of patients undergoing keratoplasty in a tertiary care center

Purpose: The purpose of the study was to study keratoplasty indications and outcomes at a tertiary care center in Western Vidarbha. Subjects and Methods: It is a retrospective cross-sectional study in which medical records of all patients undergoing keratoplasty at tertiary care in Western Vidarbha, Maharashtra, India, between October 2021 and October 2023, with a minimum follow-up period of 6 months were reviewed. Data were represented as numbers, percentages, and means. Study Parameters: Indications, surgical procedures, and outcomes of all surgeries collected and studied. Main Outcomes: Graft survival and visual acuity. Results: One hundred cases of keratoplasty were recorded during the study period. Total (33) optical keratoplasties, (41) therapeutic/tectonic keratoplasties, (11) descemet stripping endothelial keratoplasty (DSEK), and (15) deep anterior lamellar keratoplasty (DALK) were included. Out of those, 15 grafts survived and 79 grafts failed. Regrafting was done in six cases. Conclusion: Fifteen percent graft survival, visual acuity improved in 30% of patients of optical KP, 28% of patients of DSEK, and 13% of patients of DALK. The most common indication for keratoplasty was a perforated corneal ulcer. Graft failures are seen in infected and rheumatoid arthritis cases commonly. Postoperative complications occurred in 73% of cases. The outcome was better in optical keratoplasty patients than in therapeutic.

Indications and Outcomes of Emergency Keratoplasty in a Major New Zealand Eye Tertiary Referral Center, 2000 to 2021.

To report the indications and outcomes of emergency keratoplasty over a 21-year period in Greenlane Clinical Centre, the major tertiary eye referral center in Auckland, New Zealand (Aotearoa). A retrospective review of medical records of all emergency keratoplasties performed in Greenlane Clinical Centre from January 2000 to September 2021 was conducted. Demographic, preoperative, intraoperative, and 1-year postoperative data were collected. Emergency keratoplasty was performed in 102 eyes of 97 patients (54 men), comprising 5.6% of transplants performed (N = 1830) in this period. The mean age was 53 years (range = 4-95 years, SD = 20). Patients of Māori ethnicity were overrepresented (31%). Corneal perforation was present in 90% of eyes, and microbial keratitis was the most common indication. Bacteria were the most commonly isolated organisms (38%). The mean preoperative and 12-month postoperative best potential corrected distance visual acuity was 1.6 and 1.2 (logMAR), respectively. All cases of therapeutic keratoplasty achieved initial therapeutic success, with no eyes lost or requiring repeat emergency keratoplasty. Complications included nonhealing epithelial defects (19%), cataract (19%), glaucoma (15%), allograft rejection (13%), and corneal melting (5%). Fifteen cases (15%) had documented graft failure at 12 months. Multivariate analysis revealed that younger age was the only statistically significant factor associated with failure at 12 months. Emergency keratoplasty was the indication for 5.6% of keratoplasties performed. Our results compare favorably with those in the literature, possibly because of early intervention and lower incidence of fungal keratitis. The reported overrepresentation of Māori has important implications for health access and delivery in New Zealand.

Глазной тканевой банк и фемтотехнологии как основа развития кератопластики

Abstract Eye tissue bank and femtotechnologies as fundamentals for keratoplasty development E.V. Boiko, I.E. Panova, A.V. Titov, Ya.I. Masian, A.A. Varavka, D.R. Mirsaitova, O.D. Yagmurov S. Fyodorov Eye Microsurgery Federal State Institution, Saint Petersburg Branch, Saint Petersburg, Russian Federation I.I. Mechnikov North-Western State Medical University, Saint Petersburg, Russian Federation Saint Petersburg State University, Saint Petersburg, Russian Federation Bureau of Forensic Medical Examination, Saint Petersburg, Russian Federation Purpose.To evaluate development of keratoplasty in the St. Petersburg branch, taking into account eye tissue bank opening and femtotechnologies intergation. Material and methods. A retrospective analysis of the structure and quantity of keratoplasty in combination with femtosecond laser was carried in Saint Petersburg branch of S. Fyodorov Eye Microsurgery Federal State Institution. Data were analyzed regarding 2-time intervals: from 1990 to 2019 and from 2019 to 2022. Results.Between 1990 and 2019, 1367 corneal transplantations were performed (an average of 46 transplantations per year). Penetrating keratoplasty had a leading position in the structure – 1159 operations (84.8%). At the same time, the lamellar keratoplasty segment took only 15.2% (208 operations), and femtosecond laser was used only in 1% of operations (14 operations). In the period from2019 to 2023, 674 keratoplasty were performed, percentage of penetrating keratoplasty decreased to 50.8% (343 operations), and number of lamellar keratoplasty cases increased to 49.2% (331 operations). Femtosecond laser was used in 73.4% of operations (495 operations). Conclusion.Based on the results of a retrospective analysis, the advantages of eye tissue bank opening and a femtosecond laser integration into the work of the St. Petersburg branch were determined. Key words:eye tissue bank, femtosecond laser, keratoplasty

Principal Component Analysis of a Real-World Cohort of Descemet Stripping Automated Endothelial Keratoplasty and Descemet Membrane Endothelial Keratoplasty Cases: Demonstration of a Powerful Data-Mining Technique for Identifying Areas of Research.

Principal component analysis (PCA) is a descriptive exploratory statistical technique that is widely used in complex fields for data mining. However, it is rarely used in ophthalmology. We explored its research potential with a large series of eyes that underwent 3 keratoplasty techniques: Descemet membrane endothelial keratoplasty (DMEK), conventional Descemet stripping automated endothelial keratoplasty (ConDSAEK), or ultrathin-DSAEK (UT-DSAEK). All consecutive DMEK/DSAEK cases conducted in 2016 to 2022 that had ≥24 months of follow-up were included. ConDSAEK and UT-DSAEK were defined as preoperative central graft thickness ≥130 and <130 μm, respectively. Seventy-six patient, disease, surgical practice, and temporal outcome variables were subjected to PCA, including preoperative anterior keratometry, the use of sulfur hexafluoride gas (SF6) versus air for primary tamponade, and postoperative best corrected visual acuity and endothelial cell density. Associations of interest that were revealed by PCA were assessed with the Welch t test or Pearson test. A total of 331 eyes were treated with DMEK (n = 165), ConDSAEK (n = 95), or UT-DSAEK (n = 71). PCA showed that ConDSAEK and UT-DSAEK clustered closely, including regarding postoperative best corrected visual acuity, and were clearly distinct from DMEK. PCA and follow-up univariate analyses suggested that in DMEK, 1) flatter preoperative anterior keratometry (average, K1, and K2) associated with more rebubbling (P = 0.004-0.089) and graft detachment (P = 0.007-0.022); 2) graft marking did not affect postoperative ECD; and 3) lower postoperative endothelial cell density associated with SF6 use (all P > 0.001) and longer surgery (P = 0.005-0.091). All associations are currently under additional investigation in our hospital. PCA is a powerful technique that can rapidly reveal clinically relevant associations in complex ophthalmological datasets.

An Investigation of Keratoplasty Procedures and Their Outcomes in Iraq

Introduction: The treatment of corneal disorders involves the use of various forms of keratoplasty. The objective of this study was to provide a detailed description of the various types of keratoplasty procedures performed in Iraq, as well as their corresponding outcomes.&#x0D; Methods: An observational study was conducted at Al-Zahraa Teaching Hospital to document cases of keratoplasty. The collected data included age, gender, types of keratoplasty, indications, previous surgical or medical history, and postoperative outcomes. The types of keratoplasty included penetrating keratoplasty (PKP), deep anterior lamellar keratoplasty (DALK), and Descemet's stripping endothelial keratoplasty (DSEK). Additionally, we performed cataract surgery and intraocular lens (IOL) insertion for those with cataracts, using either IOLs with scleral fixation or IOLs with iris fixation. We complete the task on the first day following the purchase order, then the first week, the first month, and every six months thereafter. Prior to surgery, patients with corneal vascularization had laser photocoagulation of the blood vessels in the cornea.&#x0D; Results: Ages range from 4 to 90. People over 40 (60.8%) were the most common age group. The female prevalence was 52.9%. Right-eye illness was diagnosed 51.6% of the time. 60% of patients underwent PKP. 26.8% had DALK, 12.4% had DSEK. Post keratoplasty, the statistically-significant improvement-ratio was 68.5% as eyes best corrected visual acuity (BCVA) improvement, while 12.2% of eyes showed a decline in BCVA and 19.3% discharged with no changes in BCVA. Postoperatively, BCVA was significantly lower in cases with a duration below 1 year (1.5), and better among the duration &gt; 3 years (0.5). The greatest improvements were seen in cases with infective keratitis (-0.7), corneal dystrophies (-0.6), and advanced keratoconus (-0.7) whereas the lowest rates were documented in cases with a graft rejection (-0.3), and bullous keratopathy (-0.3)&#x0D; Conclusion: Keratoplasty is associated with a substantial enhancement of visual acuity in the younger population. Infective keratitis, keratoconus, and corneal dystrophy produce the most optimal and superior results. The PKP method is the most frequently performed.

Outcome of Optical Keratoplasty for Corneal Scar due to Infective Keratitis.

Corneal opacity is an important cause of blindness in developing countries. This study analyzes optical keratoplasty performed for corneal opacity due to infective keratitis. This is a retrospective study of all consecutive cases of optical keratoplasty performed between 2011 and 2014 (four-year period) for healed infective keratitis. Cases with less than two months' followup were excluded during outcome evaluation. Comparison was made between keratoplasty for Microbial and Viral (herpetic) Scar. Ninety-three eyes of 93 patients were enrolled. Fifty-nine (63.4%) were male. Average age of patients was 38.9±19.5 years. Average donor endothelial cell count was 2713±434.5 cells/mm2. Fifty-four (58%) corneal scars were due to microbial keratitis and others were herpetic. Eighty-five (91.4%) had undergone penetrating keratoplasty. Eighty-eight (94.6%) cases were included for outcome analysis. Average follow-up duration was 37±27.5 months. Fifty-two (59%) had clear graft at their last visit. Twenty-three (26.1%) grafts had endothelial failure and 13 (14.7%) grafts failed due to late onset keratitis. Twenty-five (28.4%) had vision of ≥6/18. Rejection occurred in 24(27.2%) and glaucoma in 11(12.5%). Post-operatively viral keratitis in the graft occurred significantly more inViral Scar Group (38.6%, n=15) than in Microbial Scar Group (5.5%, n=3). But there was no significant difference in graft clarity, rejection, vision and secondary glaucoma between the two Groups. Outcome of keratoplasty for post-infectious scars was found fairly satisfactory. Although occurrence of viral keratitis was higher in case of keratoplasty done for Viral Scars, the final result was similar to that of microbial scar.

Reverse 4-Throw Pupilloplasty for Endothelial Keratoplasty.

The aim of this study was to describe the feasibility and applicability of a reverse 4-throw (RFT) pupilloplasty technique for endothelial keratoplasty. In RFT, the 9-0 polypropylene suture needle and a 26-Gauge needle pierce the iris tissue from the posterior surface to emerge on the anterior surface along the proximal and distal portion of iris tissue to be apposed, respectively. The 9-0 needle is threaded into the barrel of a 26-Gauge needle and is withdrawn from the eye. The suture loop is withdrawn and the suture end is passed through the loop 4 times. Both suture ends are pulled, which leads to the sliding of the loop inside the eye, thereby apposing the iris tissue with the knot lying on the posterior surface. The procedure was performed in 11 eyes of 11 patients who were scheduled to undergo an endothelial keratoplasty procedure. The anterior segment optical coherence tomography image of the RFT pupilloplasty did not denote any presence of the suture in the anterior chamber or along the anterior surface of the iris plane. No incidence of primary graft failure or graft rejection during the entire follow-up period was reported in any of the eyes. RFT serves as an effective technique for performing pupilloplasty in endothelial keratoplasty cases without the presence of a knot or suture tail in the anterior chamber.

"Partial Open Sky Method" - A novel technique to avoid the open sky condition during Triple procedure or Penetrating keratoplasty.

Penetrating keratoplasty is referred to as an "open-sky" procedure because the intraocular contents are entirely exposed to atmospheric pressure after the diseased cornea has been trephined off and before the donor button is sutured. Suprachoroidal hemorrhage (SCH) is a major vision-threatening complication, associated with this open-sky procedure. While numerous factors may predispose an eye to SCH, like hypertension, myopia, trauma, glaucoma, etc., it is better to be prepared for the worst eventuality. We described a novel technical modification, denoted as the "partial open sky technique", that we used during the surgical steps of trephining and excision of host corneal tissue in seven cases of triple procedure and penetrating keratoplasty in our center over two months. We propose that the technique would be additionally helpful in managing the inadvertent suprachoroidal hemorrhage associated with keratoplasty over the available existing methods. Abbreviations: SCH = Suprachoroidal hemorrhage, ICCE = Intracapsular cataract surgery, ECCE = Extracapsular cataract surgery, WTW = White to White.

Lost-to-follow-up: A study on corneal transplantation from Eastern India.

This study aims to analyze the pattern of follow-ups and the reasons for follow-up loss in keratoplasty cases in a tertiary eye care center. This is a single-center retrospective cross-sectional study. During the study period, 165 eyes underwent corneal transplantation. The data on the demographic features of the recipients and the indications of keratoplasty, including visual acuity before and after surgery, duration of follow-up, and the condition of the graft at the last follow-up, were collected. The primary outcome was to determine the factors causing lost-to-follow-up (LTFU) among graft recipients. LTFU was defined when a patient failed to adhere to any of the following seven follow-up visits since the surgery: 4 ± 2 weeks, 3 ± 1 months, 6 ± 1 months, 12 ± 2 months, 18 ± 2 months, 24 ± 3 months, and 36 ± 6 months. The secondary outcome was to analyze the best-corrected visual acuity (BCVA) among patients available for the final follow-up. The recipient follow-up rates at 6, 12, 18, 24, and 36 months were 68.5%, 57.6%, 47.9%, 42.4%, and 35.2%, respectively. Old age and distance to the center were significant factors for lost-to-follow-up. A failed graft as an indication for transplantation and those undergoing penetrating keratoplasty for optical purposes were significant factors for completing follow-up. The inability to follow-up after corneal transplantation is a common challenge. Elderly patients and those living in remote areas must be prioritized for follow-ups.

Bilateral Simultaneous Penetrating Keratoplasty: A 40-Year Odyssey

Purpose: The purpose of this study was to report 40-year follow-up on a case of bilateral simultaneous penetrating keratoplasty (PK) involving a contralateral autograft. Methods: This was a case report. Results: A 39-year-old man developed right corneal scarring and lipid keratopathy from previous herpes zoster keratouveitis with visual acuity of 20/200. The left eye had dense amblyopia with visual acuity of 20/300. In 1980, he underwent right PK using a contralateral autograft and simultaneous left PK with an allograft. The right autograft provided excellent visual acuity until the graft failed 40 years later. The left allograft underwent severe endothelial graft rejection 2 months after surgery with gradual corneal clearance over the next 21 months. The left allograft remained clear through 40 years without graft failure. Conclusions: Long-term useful vision and graft survival were achieved with a penetrating autograft by avoiding endothelial graft rejection in the setting of previous herpes zoster keratitis and the patient being functionally monocular. Despite almost failing from severe endothelial graft rejection in the absence of ocular risk factors, the left allograft recovered and remained clear through 40 years possibly because peripheral host endothelial cells repopulated the donor.

Clinical outcome of first hundred consecutive therapeutic penetrating keratoplasties done at a tertiary eye care centre in Eastern India

ABSTRACT Aim: To analyze the clinical outcome of first 100 consecutive cases of therapeutic penetrating keratoplasty (TPK) done at a tertiary eye care centre in Eastern India. Materials and Methods: A retrospective analytical observational study of first 100 consecutive patients of TPK was done at RIO, IGIMS, Patna, Bihar for nonhealing keratitis with or without perforation with a minimum 1 year follow up examination. Patients with vitreous exudates were excluded from the study. Results: Organisms were isolated in 60% of cases of which 65% were fungi (Aspergillus), 20% were bacteria, (Staphylococcus aureus) and 15% had mixed infection. 17 cases required lens removal during surgery. Repeat graft infection was noticed in 23 cases of which 9 had fungi, 2 had bacterial isolate and rest was inconclusive preoperatively. A repeat TPK was performed in 7 patients out of the reinfected cases. Anatomical restoration could be achieved in 96% of cases. Graft clarity allowing clear view of anterior chamber could be seen in 26 cases. 4 cases of graft infection with posterior segment involvement finally required evisceration. 47 out of 100 TPK cases had raised intraocular pressure (IOP) of which 10 underwent glaucoma surgery for uncontrolled IOP despite medications. Conclusion: TPK is a challenging surgery still having definite role in management of nonresponding progressive keratitis. Maintaining graft clarity postoperatively is a difficult task in these cases therefore success should be measured in terms of infection eradication and anatomical restoration.

Deep Anterior Lamellar Keratoplasty: Can All Ruptures Be Fixed?

The aim of this study was to report our experience in managing different types of Descemet membrane (DM) ruptures during deep anterior lamellar keratoplasty (DALK). This study was a retrospective, consecutive, interventional case series of 1573 DALK procedures conducted on 1244 patients, performed between 2002 and 2017. Inclusion criteria consisted of a minimum of 24-month follow-up. DM rupture incidence, location, and surgical approach for repair were recorded. Postoperative measures were investigated only in eyes that experienced DM ruptures and included best spectacle-corrected visual acuity, endothelial cell loss, double anterior chamber, pupillary block, need for rebubbling, graft clarity, and rejection episodes. One thousand four hundred forty-three eyes met the inclusion criteria. DM ruptures occurred in 119 eyes (8.25%). Seventy-eight percent of DM ruptures were microruptures (≤2 mm), and they occurred more frequently during manual DALK cases. Macroruptures were less frequent (22%), and they occurred more frequently during subtotal and total anterior lamellar keratoplasty (STALK-TALK) cases. In general, DM ruptures mainly occurred in the peripheral cornea (95% of cases). One hundred (84%) of the 119 ruptures resolved by the first postoperative day. Nineteen cases (16%) developed double anterior chamber; all resolved by using different strategies. No intraoperative penetrating keratoplasty conversion was recorded. Pupillary block occurred in 7 cases (5.9%), but no Urrets-Zavalia syndrome was observed. The average postoperative endothelial cell loss was 410 ± 39 cells/mm 2 (19%) at 1-year follow-up, and there was no significant difference between cases requiring a rebubbling and cases that did not ( P = 0.896). All grafts but one were clear at the last follow-up. Graft failure from endothelial decompensation occurred in this lone case (0.8%). It is worth trying to repair all DM ruptures in DALK, and immediate penetrating keratoplasty conversion should be avoided. Understanding the physiomechanical mechanisms in DALK allows to correctly choose a proper rescue strategy to successfully repair DM ruptures.

Reverse graft suturing to avoid Descemet's membrane detachment of glycerol-preserved donor cornea used for therapeutic penetrating keratoplasty during COVID-19 to overcome the tissue shortage - A novel surgical technique.

To overcome tissue shortage during pandemic, we switched to 100% glycerol preservation of the donor cornea, which is economical and provides longer duration of storage than the short and intermediate storage mediums we normally use like McCAREY Kaufman (MK) or cornisol. During our initial few cases of therapeutic penetrating keratoplasty using glycerol preserved donor cornea, we faced spontaneous Descemet’s detachments resistant to air tamponade. We tried reverse graft suturing and successfully reinforced Descemet’s attachment along with air tamponade, in one of the cases after multiple failed air injections. In the subsequent two cases of infective keratitis needing therapeutic penetrating Keratoplasty, we took eight reverse sutures in between the eight cardinals, to anchor the Descemet’s membrane of the graft. Both the grafts showed attached Descemet’s and maintained good graft clarity. The reverse corneal suturing technique has not been described to the best of our knowledge and hope this helps our corneal fraternity.

Techniques, Outcomes, and Complications of Preloaded, Trifolded Descemet Membrane Endothelial Keratoplasty Using the DMEK EndoGlide.

To describe 2 insertion techniques, outcomes, and complications of preloaded, trifolded Descemet membrane endothelial keratoplasty (DMEK) cases using the DMEK EndoGlide inserter. This retrospective, consecutive case series analyzed the first 35 cases using the DMEK EndoGlide performed between October 2018 and October 2019 at a single center. Preloaded, trifolded DMEK tissues were delivered through a fluid-injected or pull-through technique. To inject the tissue, a burst of fluid was delivered into the lumen of the injector with a second instrument. Postoperatively, best-spectacle corrected visual acuity (BSCVA), pachymetry, graft survival, and complications were assessed. Thirty-five eyes of 29 patients underwent DMEK alone (n = 11), with cataract surgery (n = 21), or with additional surgeries (n = 3). Of these, 19 (54.3%) grafts were injected. Video analysis revealed a median time of 3.5 minutes from graft insertion to opening for gas insertion. Median preoperative BSCVA of 0.398 logMAR improved to 0.097 logMAR (P = 0.02) at 9 months. Median pachymetry decreased from 619 μm to 551 μm (P = 0.03) at 9 months. Median donor endothelial cell count of 2890.5 cells/mm2 reduced to 2123 cells/mm2 (26.6% endothelial cell loss; P = 0.008) 6 months postoperatively. One (2.9%) graft failed due to inverted marking at the eye bank and subsequent reverse implantation. Pre-loaded, tri-folded tissues can be implanted with acceptable levels of endothelial cell loss. We describe a no-touch method of injecting pre-loaded, tri-folded tissue and highlight incorrect marking as a potential complication. This may not be identifiable intraoperatively due to lack of scroll formation.

Intraoperative Optical Coherence Tomography: Game-Changing Technology.

Intraoperative optical coherence tomography (OCT) has the potential to revolutionize lamellar corneal surgery and facilitate many other types of ocular surgery because it readily visualizes ocular structures that can be difficult to discern with a coaxial microscope, particularly through a cloudy cornea. Systems that can provide a high-quality image on demand in the surgeon's oculars, rather than just on an adjacent monitor, are the most useful because they allow the surgeon to rely on the OCT image while operating, without having to look away from the surgical field. Useful applications in lamellar corneal surgery include assessing graft attachment with Descemet stripping endothelial keratoplasty and discerning graft orientation with Descemet membrane endothelial keratoplasty, which otherwise could be challenging in an eye with a cloudy cornea. Intraoperative OCT is particularly helpful when performing deep anterior lamellar keratoplasty in cases in which a big bubble should not be attempted or cannot be achieved because it enables better intraoperative control of the incision depth and allows the surgeon to assess the uniformity of the dissection plane to optimize visual outcomes. Intraoperative OCT is also useful when judging the depth of a scar for a lamellar dissection, when evaluating intraocular lens positioning in the capsular bag, or when locating and removing retained nuclear fragments from an eye with a poor view because of a cloudy cornea. The primary barrier to the adoption of this valuable technology is cost.

Novel Microforceps Technique Developed for Endothelial Surgical Procedures.

To develop a more efficient and less traumatic method of Descemet membrane removal in endothelial surgery. A novel, vertically oriented, reverse-grasping microforceps (named the Rabiyah Descemet Membrane Removal Microforceps) were created to facilitate grasping and extraction of a host Descemet membrane. This new instrument has been used successfully and safely in more than 85 endothelial keratoplasty cases among 4 surgeons. The Rabiyah Descemet Membrane Removal Microforceps provides surgeons with a safe and an efficient option to remove Descemet membrane in endothelial surgical procedures.

Intraoperative fibrin formation during Descemet membrane endothelial keratoplasty

PurposeTo describe Descemet membrane endothelial keratoplasty (DMEK) cases complicated by spontaneous intraoperative fibrin formation. MethodsDMEK surgeries performed at two centers using a standardized technique were reviewed retrospectively for the occurrence of intraoperative fibrin formation. Cases were assessed for recipient medical history, donor age, best spectacle-corrected visual acuity (BSCVA), intraoperative unscrolling time, 6-month endothelial cell loss (ECL), and the course of the mate donor cornea. ResultsIn this review of 868 cases of standardized DMEK surgery with surgical peripheral iridotomy, 32 eyes of 29 patients (3.7%) were complicated by the formation of intraoperative fibrin formation, including 3 patients that developed fibrin in both eyes. Three of the 32 grafts failed (9.4%). None of the mate corneas transplanted (n = 27) developed complications related to fibrin. The donor age ranged from 51 to 75 years and recipient age ranged from 49 to 82 years (median, 66 years). Unscrolling time ranged from 1 to 105 min (median, 15 min). Nine eyes required one rebubble procedure. No eyes had vision-limiting comorbidities, and the 6-month BSCVA was ≥20/40 in all eyes. Six-month ECL ranged from 19% to 73% (median, 44%). ConclusionsWe conclude that fibrin formation during DMEK surgery is an uncommon but important complication that can make graft manipulation more difficult, and may have deleterious effects on endothelial cell density and graft survival.

Phototherapeutic keratectomy: Indications, methods and decision making.

Phototherapeutic keratectomy (PTK) involves treating anterior corneal lesions by superficial corneal ablation using an excimer laser (193 nm). Some of the commonly treated conditions include recurrent corneal erosions (RCE), corneal dystrophies, spheroidal degeneration, keratoconus, and corneal scars. We discuss various techniques of PTK including large area PTK, focal PTK, and multifocal PTK and alternatives to PTK. Masking agents like hyaluronate, methylcellulose, and dextran are recommended to help achieve a better outcome when ablating irregular corneal surfaces. Antifibrotic agents like mitomycin C reduce the chances of recurrence of the disease, apart from minimizing the postoperative scarring. Some of the complications include induced hyperopia and irregular astigmatism, haze, recurrence, and corneal thinning. However, earlier postoperative recovery, possibility of a repeat procedure, and ability to control the depth of ablation make PTK a promising, minimally invasive alternative to keratoplasty in cases with anterior corneal pathologies.

Effect of Surgical Indication and Preoperative Lens Status on Descemet Membrane Endothelial Keratoplasty Outcomes

To analyze 6-month results of 1000 consecutive Descemet membrane endothelial keratoplasty (DMEK) cases, and to evaluate if outcomes are influenced by surgical indication and preoperative lens status. Retrospective, interventional case series. A series of 1000 eyes (738 patients) underwent DMEK mainly for Fuchs endothelial corneal dystrophy (FECD; 85.3%) or bullous keratopathy (BK; 10.5%). Main outcome measures were best-corrected visual acuity (BCVA), endothelial cell density, postoperative complications, and retransplantations. At 6months after DMEK, there was no difference in BCVA outcome between FECD and BK eyes (P= .170), or between phakic and pseudophakic FECD eyes (P= .066) after correcting for patient age and preoperative BCVA. Endothelial cell loss at 6months postoperatively was similar for phakic and pseudophakic FECD eyes (39%; P= .852), but higher for BK eyes than for FECD eyes (46% vs 39%, P= .001). Primary and secondary graft failure occurred in 3 (0.3%) and 2 eyes (0.2%), respectively, and 7 eyes developed allograft rejection (0.7%). Eighty-two eyes (8.2%) received rebubbling for graft detachment and retransplantation was performed in 20 eyes (2.0%). Rebubbling was more often required in eyes treated for BK vs FECD eyes (12.4% vs 7.4%, P= .022). DMEK consistently provides excellent short-term results, with similar high visual acuity levels for both FECD and BK eyes. As preoperative lens status did not influence DMEK outcomes, for phakic FECD eyes with a still relatively clear crystalline lens, lens preservation may be preferable in a selected group of younger patients, who may still benefit from their residual accommodative capacity.

Learning Descemet Membrane Endothelial Keratoplasty: A Survey of U.S. Corneal Surgeons.

The transition to Descemet membrane endothelial keratoplasty (DMEK) is frequently challenging, requiring the adoption of new techniques, skills, and methods. We sought to draw on surgeons' initial experiences with DMEK to characterize the learning curve associated with this procedure and identify factors that could be linked to the frequency of primary graft failure (PGF) in the first 10 cases. We invited corneal surgeons based in the United States who started performing the DMEK procedure within the past 2 years to answer a 12-question survey using an online survey platform. We analyzed quantitative and qualitative data. A Fisher exact test was used to determine whether preoperative approaches to preparation were associated with decreased PGF rates. A total of 100 US-based corneal surgeons replied from 34 of 50 states. Of these, 68% reported that DMEK comprised a majority of their endothelial keratoplasty cases. Approximately half of surgeons (52%) had performed more than 20 DMEK cases by the time of the survey, and 51% felt equally comfortable performing DMEK relative to Descemet stripping endothelial keratoplasty. Among the respondents, 37% answered that they had experienced PGF in the first 10 cases. Scrubbing in with an experienced colleague before surgery was associated with a decreased likelihood of at least one case of PGF (31%, P = 0.049), but not participation in a wet lab with an experienced instructor or mentor (38%, P = 0.50), nor having an eye bank representative present in the operating room (43%, P = 0.886). The collective experience of 100 surgeons beginning DMEK confirms the importance of mentorship and that the accompaniment of an experienced colleague during the learning curve is associated with lower rates of PGF.