Intracameral Fibrinous Reaction During Descemet's Membrane Endothelial Keratoplasty.

PURPOSE: To determine the outcomes and predisposing factors of Descemet's membrane endothelial keratoplasty (DMEK) complicated by intraoperative fibrinous reaction. METHODS: Retrospective cohort study of 346 DMEKs. Medical charts were reviewed for recipient demographics, surgical indications, donor characteristics, and potential predisposing ocular and systemic factors. For DMEKs complicated by fibrin, surgeons' notes on events leading to fibrin formation and on its intraoperative management, occurrence of graft detachment, primary failure, re-bubbling or regrafting, time to graft clearing, and endothelial cell density were additionally collected. RESULTS: Fifteen (4.3%) DMEKs were complicated by fibrin, which interfered with and protracted graft unfolding in all cases. Median surgical time was longer than for uncomplicated DMEKs (p = 0.001). Graft positioning at the end of surgery was suboptimal in seven eyes (47%) and failed in three (20%). Re-bubbling, primary failure, and regraft rates were of 40%, 33% and 53%, respectively. The corneas that cleared did so in three to eight weeks, with median endothelial cell loss of 53% at 12 months. Use of anticoagulants was a preoperative risk factor (p = 0.01). Surgeon-identified intraoperative factors included beginner surgeons (87%), prolonged AC shallowing (47%) and graft manipulations (33%), intraocular bleeding (27%), new injector (20%), tight donor scroll (13%), and floppy iris (13%). CONCLUSION: Fibrinous reaction is a rare intraoperative complication of DMEK that interferes with graft unfolding and results in poor outcomes. Anticoagulant use appears to be a risk factor and may be compounded by surgical trauma to vascular tissues and prolonged surgical maneuvers.

Descemet membrane endothelial keratoplasty in patients with prior glaucoma surgery.

OBJECTIVE: To present outcomes of Descemet membrane endothelial keratoplasty (DMEK) in eyes with prior trabeculectomy or a glaucoma drainage device (GDD). METHODS: A retrospective case series, including patients that had previously undergone trabeculectomy and/or GDD implantation, who later underwent DMEK between 2013 and 2016 at Toronto Western Hospital and the Kensington Eye Institute. Outcome measures: best spectacle-corrected visual acuity (BSCVA), endothelial cell (EC) density, intraoperative and postoperative complications. RESULTS: Twenty-seven eyes of 27 patients were included. All DMEK procedures were uneventful. Mean follow-up time was 14.6 ± 6.1 months. In eyes with no visually limiting comorbidities (n = 16), BSCVA improved from 1.34 ± 0.65 logMAR (Snellen equivalent ~20/440) preoperatively to 0.51 ± 0.24 logMAR (Snellen equivalent ~20/65) and 0.50 ± 0.33 logMAR (Snellen equivalent ~20/65) at 6 and 12 months, respectively (p < 0.001 for both). In eyes with visually limiting comorbidities (n = 11), BSCVA improved from 1.92 ± 0.72 logMAR (Snellen equivalent ~20/1665) preoperatively to 1.43 ± 0.83 logMAR (Snellen equivalent ~20/540) and 1.37 ± 0.99 logMAR (Snellen equivalent ~20/470) at 6 and 12 months, respectively (p = 0.008 and p = 0.037).Graft detachment rate was 24.1% and rebubble rate was 17.2%. Primary and secondary graft failure rates were 3.7% and 10.3%, respectively. Rejection rate was 17.2%. EC-loss rate at 6 months and 12 months was 36.7% and 50.5%, respectively. CONCLUSIONS: DMEK performed in eyes with previous trabeculectomy or a GDD is more challenging than conventional DMEK, but has good outcomes. Higher rates of graft rejection and secondary graft failure in this setting should be further evaluated in long-term studies.

Four-Year Survival of Descemet Membrane Endothelial Keratoplasty in Patients With Previous Glaucoma Surgery.

PURPOSE: To evaluate 4-year outcomes of Descemet membrane endothelial keratoplasty (DMEK) in eyes with previous glaucoma surgery. DESIGN: Retrospective, comparative case series. METHODS: Patients with previous trabeculectomy or glaucoma drainage device (GDD) implantation who later underwent DMEK (study group) were matched for follow-up duration with Fuchs dystrophy DMEK patients (control group). The minimum follow-up was 18 months. Primary outcomes included graft survival and rejection rates, and secondary outcomes included rates of detachment/rebubble, endothelial cell loss, best spectacle-corrected visual acuity, intraocular pressure, and glaucoma medications/surgeries. Subgroup analysis compared eyes with and without a GDD. RESULTS: Ninety-four eyes of 91 patients were included. There were 51 eyes of 49 patients in the study group (GDD = 32 eyes, no GDD = 19 eyes) and 43 eyes of 42 patients in the control group. The mean follow-up was 37.9 ± 15.2 and 33.8 ± 13.5 months, respectively (P = .322). Graft survival probability of the study group at 12, 24, 36, and 48 months was 75%, 60%, 43%, and 27%, respectively, compared with a consistent 88% in the control group (P < .001). Survival curves of study subgroups (GDD and no GDD) were significantly lower than the control group (P < .001). Rejection rates in the study and control groups were 19.6% and 2.3%, respectively (P = .010). Endothelial cell loss in the study group was 12%-22% higher than the control group at 12, 24, 36, and 48 months (P = .049, P = .027, P = .200, and P = .004). CONCLUSIONS: In eyes with previous glaucoma surgery, DMEK has good early outcomes, but longer-term rejection and failure rates are high. Physicians and patients should be cognizant of the high likelihood of graft failure in this setting.

Poor Long-Term Outcomes of Keratopigmentation With Black Ink for the Treatment of Dysphotopsia Secondary to Laser Peripheral Iridotomies.

PURPOSE: To report outcomes of keratopigmentation (KP) with commercial black ink in the treatment of dysphotopsia secondary to laser peripheral iridotomies (LPI) using manual anterior stromal puncture (ASP) and manual lamellar pocket (LP). METHODS: This is a retrospective case series of eyes that underwent KP for treatment of dysphotopsia secondary to LPI. Patients' postoperative symptoms were categorized as resolved, improved, no change, or worse. Any intraoperative and postoperative complications were noted, as well as the need for further treatments. RESULTS: Five eyes in 4 patients underwent ASP, and 14 eyes in 13 patients underwent LP. Only 1 patient had improvement in symptoms in the AK group. Four patients had a complete resolution of symptoms after LP, whereas 7 had symptomatic improvement and 3 did not notice any change. Fifty-five percent of patients in the LP group experienced late-onset depigmentation between 3 and 5 years postoperatively. One patient who underwent 2 LP re-treatments experienced irregular corneal steepening with nonprogressive corneal thinning. Overall, there were no serious adverse reactions to the pigment used. CONCLUSIONS: ASP was not suitable for the treatment of dysphotopsia secondary to LPI. In the short term, LP had good outcomes, but commercial black ink was prone to depigmentation at 3 to 5 years postoperatively. We therefore do not recommend the use of such pigment for long-term management of dysphotopsia secondary to LPI.

Comparison of Descemet Stripping Automated Endothelial Keratoplasty and Descemet Membrane Endothelial Keratoplasty in the Treatment of Failed Penetrating Keratoplasty.

PURPOSE: To compare the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) with Descemet membrane endothelial keratoplasty (DMEK) for the treatment of failed penetrating keratoplasty (PKP). METHODS: This is a retrospective chart review of patients with failed PKP who underwent DMEK or DSAEK. The median follow-up time for both groups was 28 months (range 6-116 months). Data collection included demographic characteristics, number of previous corneal transplants, previous glaucoma surgeries, best-corrected visual acuity, endothelial cell density, graft detachment and rebubble rate, rejection episodes, and graft failure. RESULTS: Twenty-eight eyes in the DMEK group and 24 eyes in the DSAEK group were included in the analysis. Forty-three percent of eyes in the DMEK group and 50% of eyes in the DSAEK group had to be regrafted because of failure (P = 0.80). The most common reason for failure was persistent graft detachment (58%) in the DMEK group and secondary failure (58%) in the DSAEK group; hence, the time between endothelial keratoplasty and graft failure differed significantly between the groups (P = 0.02). Six eyes (21%) in the DMEK group and 7 eyes (29%) in the DSAEK group developed graft rejection (P = 0.39). Rejection was the cause of failure in 67% and 71% in the DMEK and DSAEK groups, respectively. The best-corrected visual acuity 6 months after surgery was better in the DMEK group compared with the DSAEK group (P = 0.051). CONCLUSIONS: Both DSAEK and DMEK have a role in treating PKP failure. Primary failure due to persistent graft detachment was significantly higher in the DMEK group, although the overall failure rate in the medium term was similar.

Successful management of severe post-LASIK Mycobacterium abscessus keratitis with topical amikacin and linezolid, flap ablation, and topical corticosteroids.

This is a case report of post-laser in situ keratomileusis (LASIK) multidrug-resistant Mycobacterium abscessus keratitis managed with combined topical amikacin and linezolid, flap amputation, and corticosteroids. A 34-year-old woman presented with a corneal interface infiltrate 3 weeks after LASIK. Cultures isolated mycobacteria. The infiltrate did not improve under intensive topical therapy and interface irrigation with empiric antibiotics over 5 weeks, and the infiltrate progressed to severe inflammation and stromal neovascularization. After identification of M abscessus susceptible only to amikacin and linezolid, antimicrobials were adjusted and the flap was ablated. Cultures repeated 1 week later came back negative. However, stromal inflammation and neovascularization persisted. Topical steroids achieved regression of the inflammation within 1 week. Identification of the mycobacterial pathogen and its susceptibilities is essential given the possibility of multidrug resistance. Topical linezolid can be effective in susceptible species. Corticosteroids can be helpful in cases with severe inflammation.

Descemet membrane endothelial keratoplasty in iridocorneal endothelial syndrome and posterior polymorphous corneal dystrophy.

OBJECTIVE: To report the clinical outcome of Descemet membrane endothelial keratoplasty (DMEK) in cases of corneal decompensation secondary to iridocorneal endothelial syndrome (ICE) or posterior polymorphous corneal dystrophy (PPCD). DESIGN: Retrospective interventional case series. PARTICIPANTS: Eight eyes of 7 patients that underwent DMEK due to corneal decompensation secondary to either ICE syndrome or PPCD, and had at least 6 months of postoperative follow-up. METHODS: Data were collected on best corrected visual acuity (BCVA), graft attachment and survival, endothelial cell density (ECD), and intraocular pressure (IOP). BCVA change, ECD loss, and IOP elevations were analyzed. RESULTS: Patients' age was 51.5 ± 13.3years. Four eyes (4 patients) had ICE syndrome and 4 eyes (3 patients) had PPCD. All procedures were uneventful. Follow-up time was 11.3 ± 7.6 months (range 6-24 months). DMEK was combined with goniosynechiolysis in 3 eyes and iridoplasty in 1 eye. BCVA improved in all eyes. Mean BCVA improved from 0.70 ± 0.34 logMAR (Snellen equivalent ∼20/100; range 20/50-20/400) preoperatively to 0.21 ± 0.14 logMAR (Snellen equivalent ∼20/34; range 20/20-20/40) at the final follow-up (p = 0.008). Donor ECD was 2740 ± 193 cells/mm2 preoperatively and 1967 ± 277 cells/mm2 at 6 months after surgery (p = 0.010)-cell loss rate of 27.8%. There were no graft rejections and no graft failures. Postoperative IOP rise (steroid response) was seen in 2 eyes, and was managed successfully with topical medical treatment. There was no evidence of glaucoma progression in any of the cases. CONCLUSIONS: DMEK surgery was effective in treating corneal decompensation secondary to ICE syndrome and PPCD. Adjunct procedures can be simultaneously combined with DMEK to address other disease aspects.

Evaluation of Big Bubble Technique for Deep Anterior Lamellar Keratoplasty in Patients With Radial Keratotomy.

PURPOSE: To report the outcome of deep anterior lamellar keratoplasty (DALK) and success rates of the big-bubble (BB) technique or manual dissection after a failed use of the BB technique in eyes that underwent prior radial keratotomy (RK). METHODS: A retrospective chart review of patients who underwent DALK after RK at Toronto Western Hospital, Canada, between 1999 and 2017 was performed. Demographic characteristics, success rates of the BB technique and manual dissection, intraoperative and postoperative complications, and best spectacle-corrected visual acuity before and after corneal transplant were analyzed. RESULTS: Ten eyes of 9 patients were included in the analysis. The average age was 64 ± 10 years (range 49-82). The average time between the RK surgery and the corneal transplant was 20 ± 5 years (range 8-24). Indications for corneal transplant were significant irregular astigmatism in 5 eyes (50%), central scarring or haze in 4 eyes (40%), and progressive hyperopia with visual fluctuation in one eye (10%). BB was successfully achieved in one eye (10%). In 6 eyes (60%), manual dissection was performed, and in 3 eyes (30%), DALK surgery was converted to penetrating keratoplasty. The average best spectacle-corrected visual acuity on the last follow-up visit was 0.26 ± 0.08 logMAR (Snellen equivalent 20/36). One eye that underwent manual DALK and one eye that underwent penetrating keratoplasty developed a rejection episode 4 and 2 months after keratoplasty, respectively. In both cases, rejection resolved with topical steroids. CONCLUSIONS: In eyes that underwent prior RK, DALK by manual dissection should be considered as a preferable surgical technique.

Outcomes of the first 250 eyes of Descemet membrane endothelial keratoplasty: Canadian centre experience.

OBJECTIVE: To report and analyze the clinical outcomes of the first 250 cases of Descemet membrane endothelial keratoplasty (DMEK). METHODS: A retrospective case series was conducted on the first 250 DMEK cases. The cohort included eyes with previous trabeculectomy, pre-existing glaucoma drainage device, and previous vitrectomy. Outcomes measures were best spectacle-corrected visual acuity (BSCVA), endothelial cell loss (ECL), episodes of rejection, detachment, rebubbling rate, and the need for repeat transplantation. Subgroup analysis was performed between eyes with different etiologies and between different DMEK injectors. RESULTS: The median BSCVA increased from 0.6 [0.4, 1.3] logMAR (Snellen equivalent, 20/80) before surgery to 0.3 [0.2, 0.5] logMAR (Snellen equivalent, 20/40) 6 months after DMEK (p < 0.001). The median ECL at 6 months after surgery was 26.1%. Thirty-nine eyes (15.6%) had graft detachment involving more than one third of the graft and required rebubbling. Two eyes (0.8%) had a graft rejection episode. Fifteen eyes (6%) had graft failure for which 13 eyes (5.2%) had repeat DMEK, 1 eye (0.4%) had repeat Descemet stripping automated endothelial keratoplasty (DSAEK), and 1 eye (0.4%) had repeat penetrating keratoplasty (PKP). Fuchs' patients and failed PKP patients gained more vision at 6 months post-DMEK compared with other etiologies (pseudophakic bullous keratopathy and failed DSAEK) (p < 0.001). CONCLUSIONS: Our data suggest that DMEK is a safe and effective procedure with excellent visual outcomes. DMEK can be done in association with other co-morbidities such as post-trabeculectomy, glaucoma drainage device, previous vitrectomy, and failed corneal grafts with a good prognosis.

Bilateral BrightOcular iris implants necessitating explantation and subsequent endothelial keratoplasty.

PURPOSE: To demonstrate the dangers associated with the BrightOcular iris implant, a model that had initially been touted as safer than its predecessors. OBSERVATIONS: A 41-year-old male presented with decreased vision in both eyes, approximately two years following bilateral BrightOcular cosmetic iris implantation performed in Mexico. On initial consultation, he was found to have bilateral corneal decompensation with stromal edema and a significantly reduced endothelial cell count (ECC). On follow up 5 weeks later, his vision and corneal edema had further detriorated. In the following month, he underwent explantation of the cosmetic iris implants in both eyes. Significant corneal edema persisted in the right eye several months post-operatively, to the point of necessitating endothelial keratoplasty. CONCLUSIONS AND IMPORTANCE: Despite numerous reports in the literature of the significant ocular complications that can arise secondary to cosmetic iris implantation, individuals continue to willingly undergo this surgery. Our intention with presenting this case to the ophthalmologic community is two-fold: to highlight the ongoing clinical risk that BrightOcular devices pose, despite being marketed as safer than the older NewColourIris models, and to stress the urgency with which cosmetic iris implants should be removed from the eye.

Simple limbal epithelial transplantation for recurrent pterygium: A case series.

PURPOSE: Pterygium recurrence is a common complication of pterygium removal. Multiple surgical and medical approaches have been utilized to reduce recurrence rates. The present case series proposes a novel way to treat recurrent pterygia, by using the simple limbal epithelial transplantation (SLET) technique. OBSERVATIONS: The cases of four patients who presented with recurrent pterygium were reviewed. In all four of the cases reported, the SLET procedure went without complication. There were no significant recurrences at each of the patient's most recent follow-up visits. CONCLUSIONS AND IMPORTANCE: This is the first report of SLET being used as a treatment modality for recurrent pterygium. Further studies are required to more reliably demonstrate the utility of the procedure in this clinical circumstance, but our results are encouraging that in select patients, this may be a viable option in treating aggressive recurrent pterygia.

Descemet Membrane Endothelial Keratoplasty After Penetrating Keratoplasty: Features for Success.

PURPOSE: To evaluate Descemet membrane endothelial keratoplasty (DMEK) in the setting of failed penetrating keratoplasty (PKP) and to identify factors associated with DMEK success and failure after PKP. METHODS: A retrospective chart review of patients who underwent DMEK for failed PKP at Toronto Western Hospital, Canada, between 2014 and 2017 was performed. Demographic characteristics, number of previous transplants, intraoperative and postoperative complications, best spectacle-corrected visual acuity (BSCVA), and endothelial cell density were analyzed. RESULTS: Twenty-eight eyes were included in the study. Rebubbling intervention was performed in 12 eyes (43%) within the first postoperative weeks. Five eyes (18%) developed graft rejection episodes. Twelve eyes (43%) had to be regrafted after DMEK surgery and were deemed failures (because of persistent Descemet membrane detachment, rejection episode that led to secondary failure, and infection). BSCVA before DMEK was significantly worse in the eyes that failed than those that did not [1.97 ± 0.85 and 1.2 ± 0.56 logMAR, respectively, (P = 0.01)]. Rebubbling was required in 75% of eyes in the failure group compared with 19% in the success group (P = 0.002). Six of the 16 eyes (37.5%) in the success group underwent femtosecond laser-enabled DMEK, whereas this technique was not used in any of the eyes in the failure group (P = 0.017). CONCLUSIONS: DMEK is a viable option for cases of failed PKP. DMEK failure after PKP might be associated with lower visual acuity before DMEK surgery, higher number of rebubble interventions, and manual descemetorhexis rather than femtosecond laser-enabled DMEK.

Outcomes of Descemet Membrane Endothelial Keratoplasty in Eyes With a Previous Descemet Stripping Automated Endothelial Keratoplasty Graft.

PURPOSE: To analyze the outcomes of Descemet membrane endothelial keratoplasty (DMEK) in eyes with previous Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: This retrospective interventional case series included 26 eyes (26 patients) that underwent DMEK to replace a previous DSAEK graft with at least 6 months of follow-up. The outcome measures were indications for surgery, best spectacle-corrected visual acuity (BSCVA), endothelial cell density, rebubbling rate, rejection, and failure. RESULTS: Patient age was 71.9 ± 12.6 years. The average follow-up time after DMEK was 15.1 ± 10.6 months. Indications for DMEK were DSAEK graft failure (69%) and a DSAEK suboptimal visual outcome (31%). BSCVA of the entire cohort (n = 26) improved from 1.33 ± 0.78 logMAR preoperatively to 1.04 ± 0.78 and 1.06 ± 0.89 logMAR at 6 months postoperatively and at the last follow-up, respectively (P = 0.019 and P = 0.033). BSCVA among eyes without visual comorbidities (n = 13) improved from 0.84 ± 0.50 logMAR preoperatively to 0.55 ± 0.47 and 0.51 ± 0.49 logMAR at 6 months postoperatively and at final follow-up, respectively (P = 0.023 for both). Of these eyes, 84.6% had improvement in BSCVA at 6 months postoperatively and at last follow-up. In the subgroup of 8 eyes with DMEK for suboptimal visual outcomes after DSAEK, BSCVA improved from 0.81 ± 0.44 to 0.52 ± 0.35 logMAR at final follow-up (P = 0.024). When excluding eyes with visual comorbidities, BSCVA of this subgroup (n = 5) improved from 0.54 ± 0.32 to 0.36 ± 0.25 logMAR at final follow-up (P = 0.038). BSCVA of this subgroup at 6 months postoperatively was not significantly different from preoperative BSCVA, when including visual comorbidities (n = 8, 0.75 ± 0.60 logMAR, P = 0.79) and when excluding visual comorbidities (n = 5, 0.40 ± 0.28 logMAR, P = 0.621). Endothelial cell density decreased from 2753 ± 307 cells/mm to 1659 ± 655 cells/mm 6 months after surgery (39.7% loss, P = 0.005). Three eyes (11.5%) required rebubbling, and 5 eyes (19.2%) had secondary graft failure at 2 to 20 months. CONCLUSIONS: DMEK is effective for replacing previous DSAEK not only for graft failure but also for suboptimal visual outcomes.

Descemet Membrane Endothelial Keratoplasty for Failed Deep Anterior Lamellar Keratoplasty: A Case Series.

PURPOSE: To suggest a new surgical approach for posterior opacities or persistent Descemet membrane (DM) detachment in failed deep anterior lamellar keratoplasty (DALK) and to report the outcome of Descemet membrane endothelial keratoplasty (DMEK) in a series of patients with DALK failure. METHODS: In this retrospective case series of patients who underwent DMEK for failed DALK at Toronto Western Hospital, 4 patients with failed DALK who underwent DMEK surgery were included. In all 4 cases, big bubble formation during initial DALK surgery had failed and the surgical technique was converted to manual dissection using the Melles technique. In 2 cases, the descemetorhexis in DMEK surgery was performed manually, and in 2 cases, the descemetorhexis was performed with the assistance of the femtosecond laser. RESULTS: Four eyes of 4 patients aged 70 ± 4 years were included. Average follow-up time was 9 ± 5 months. Indications for DALK surgery were corneal dystrophy in 2 patients and corneal scars in the other 2. DALK failure was due to persistent DM detachment that created a double chamber in 2 patients and due to posterior lamellar haze in the other 2. After DMEK surgery, 2 patients had graft detachment and required rebubbling. In 1 patient, the DMEK scroll was attached after 1 rebubble attempt, and in the other patient, a second rebubble attempt was needed. The final visual acuities were 20/40, 20/50, 20/70, and 20/200 (because of dense cataract). All procedures were uneventful. CONCLUSIONS: DMEK surgery may be effective in managing DALK failure.

Comparison of Sulfur Hexafluoride (SF6) and Air Tamponade in Noniridectomized Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To compare the efficacy and safety of 20% sulfur hexafluoride gas (SF6) and air tamponade in patients who underwent noniridectomized Descemet membrane endothelial keratoplasty (DMEK). METHODS: A retrospective chart review of patients who underwent DMEK with either air or SF6 tamponade: 41 eyes received air tamponade (group 1) and 41 received SF6 tamponade (group 2). Best spectacle-corrected visual acuity, endothelial cell density, and complications including graft detachment and elevated intraocular pressure were compared. RESULTS: The mean follow-up time was 8 ± 4 months in group 1 and 3 ± 2 months in group 2. Mean best spectacle-corrected visual acuity improved from 1.12 ± 0.88 to 0.64 ± 0.78 logarithm of the minimum angle of resolution (logMAR) in group 1 (P = 0.009) and from 1.00 ± 0.78 to 0.62 ± 0.53 logMAR in group 2 (P = 0.006). The graft detachment rate was 39% (16 eyes) in group 1 and 42% (17 eyes) in group 2 (P = 0.822). The rate of graft detachment larger than one third of the graft area was 17% in group 1 and 20% in group 2 (P = 0.775). Rebubbling was performed in 26.8% and 20% of eyes in group 1 and 2, respectively (P = 0.43). Average endothelial cell loss was 32% in group 1 and 33% in group 2 (P = 0.83). In the immediate postoperative period, elevated intraocular pressure was observed in 2 eyes (5%) in group 1 and in 4 eyes (10%) in group 2 (P = 0.4). There was 1 primary graft failure in each group. CONCLUSIONS: Use of air with it being readily available and short acting is a good method of Descemet membrane tamponade in noniridectomized DMEK.

Stepwise Guided Photorefractive Keratectomy in Treatment of Irregular Astigmatism After Penetrating Keratoplasty and Deep Anterior Lamellar Keratoplasty.

PURPOSE: To report the outcome of stepwise ablation using topography-guided photorefractive keratectomy to treat irregular astigmatism after either penetrating keratoplasty (PKP) or deep anterior lamellar keratoplasty (DALK). METHODS: This is a retrospective, interventional analysis including patients with irregular astigmatism after either PKP or DALK, who underwent topography-guided photorefractive keratectomy. The entire cohort was analyzed, as well as the PKP and DALK groups separately. Analysis of factors associated with a better outcome was also performed. RESULTS: Thirty-four eyes of 34 patients (20 PKP patients and 14 DALK patients) aged 47.4 ± 15.9 years were included. Twenty-one patients underwent more than 1 ablation. Refractive stability and a minimal period of 5 months were required before repeat ablation. The average follow-up duration was 17.0 ± 6.0 months. Corrected distance visual acuity (CDVA) improved significantly from 0.22 ± 0.14 logarithm of the minimum angle of resolution (logMAR) to 0.14 ± 0.12 logMAR at final follow-up (P = 0.035). Uncorrected distance visual acuity (UDVA) improved significantly from 0.90 ± 0.54 logMAR to 0.57 ± 0.40 logMAR at final follow-up (P = 0.004). CDVA and UDVA improved by ≥1 Snellen lines in 54.2% and 70.8% of the eyes, respectively, and by ≥3 Snellen lines in 16.7% and 54.2% of the eyes, respectively. Statistically significant improvement was seen in optical aberrometry indices (total root mean square, higher-order aberration root mean square, defocus, coma, trefoil, and spherical aberration). The difference between PKP and DALK in either CDVA (P = 0.562) or UDVA (P = 0.384) improvement was nonsignificant. CONCLUSIONS: The stepwise topography-guided photorefractive keratectomy approach in cases of irregular astigmatism after PKP or DALK can help improve visual acuity outcomes. Patients should be appropriately counseled that more than 1 treatment will likely be needed.

Topography-Guided Photorefractive Keratectomy in the Treatment of Corneal Scarring.

PURPOSE: To report the outcome of topography-guided photorefractive keratectomy (TG-PRK) in the treatment of patients with corneal scarring. METHODS: A retrospective, interventional case series including 6 eyes of 6 patients with corneal scarring and irregular astigmatism who underwent TG-PRK. The etiologies for scarring were: infectious corneal ulcers, foreign body trauma, LASIK flap buttonhole, and lamellar keratoplasties performed to correct corneal perforation secondary to corneal melting. Main outcome measures were corrected distance visual acuity, uncorrected distance visual acuity, manifest refraction, and corneal regularity on topography maps. RESULTS: Average age was 56.5 ± 19.6 years and average follow-up time was 14.8 ± 6.1 months. Three patients had corneal scarring with cataract and underwent TG-PRK to achieve sufficient regularization of corneal astigmatism to enable the implantation of a toric intraocular lens (IOL). The three remaining patients had TG-PRK performed to improve visual acuity, and all had improvement in uncorrected (improvement between one and three Snellen lines) and corrected (improvement between two and three Snellen lines) distance visual acuity. There were no intraoperative or postoperative complications and no loss of visual acuity. CONCLUSIONS: The use of TG-PRK for corneal scarring may improve visual acuity in selected cases, obviate the need for keratoplasty in some cases, and facilitate toric IOL implantation in some cases. [J Refract Surg. 2017;33(9):639-644.].

Peripheral Blunt Dissection: Using a Microhoe-Facilitated Method for Descemet Membrane Endothelial Keratoplasty Donor Tissue Preparation.

PURPOSE: To describe a modified technique for Descemet membrane donor tissue preparation that facilitates the original Melles stripping technique. METHODS: Descemet membrane is prepared using a Rootman/Goldich modified Sloane microhoe, using a blunt instrument as opposed to a sharp blade or needle and begins dissection within the trabecular meshwork. The trabecular tissue is dissected for 360 degrees, and then Descemet membrane is stripped to approximately 50%. A skin biopsy punch is then used to create fenestration in the cornea, which is used to mark an "F." on the stromal side of Descemet membrane to aid in orientation of the graft. Trephination of the membrane is then performed and stripping is completed. The tissue is stained with 0.06% trypan blue and aspirated into an injector for insertion into the anterior chamber. RESULTS: Before converting to the technique described, 5 of 75 (6.7%) tissues were wasted and 7 of 75 (9.3%) tissues with radial tears were salvaged for use. Since converting to the new technique, only 1 of 171 (0.6%) (P = 0.01) tissues was wasted and 7 of 171 (4.1%) (P = 0.2) tissues with radial tears were salvaged. CONCLUSIONS: The peripheral blunt dissection technique offers an improvement over the technique originally described by Melles et al, as the incidence of tissue wastage and tears is lower, it is easy to learn, has low stress, and is reproducible. Combining this with a stromal surface letter mark ensures correct orientation of the tissue against the corneal stroma of the recipient.