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.

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.

Systemic immunosuppression in limbal stem cell transplantation: best practices and future challenges.

The objective of this study was to evaluate systemic immunosuppression regimens used for patients undergoing ocular surface stem cell transplantation, including their benefits and adverse effects in the adjunctive management of limbal stem cell deficiency (LSCD). A systematic literature review was conducted using the MEDLINE and EMBASE databases (1980-2015). Data were collected on surgical intervention(s), type of immunosuppressive agent(s), duration of immunosuppression, percentage with stable ocular surface at last follow-up, mean follow-up time, and demographics. Data were also collected on adverse ocular and systemic outcomes. Sixteen reports met the inclusion criteria. There were no randomized controlled studies. Three studies were noncomparative prospective case series, whereas the majority were retrospective case series. Bilateral severe LSCD was the most common disease (50%), and keratolimbal allograft was the most common intervention (80%). Immunosuppressive regimens showed a progression from early studies using oral cyclosporine to later studies using combinations of mycophenolate mofetil and tacrolimus. Most studies included a course of high-dose systemic corticosteroids. For patients adherent to long-term systemic immunosuppression, stable ocular surface rates of 70%-80% at last follow-up were reported. Adverse effects included hypertension, diabetes mellitus, and biochemical abnormalities managed with pharmacotherapy or discontinuation of offending agents. There were no cases of mortality related to immunosuppression. However, the current literature does not elucidate which immunosuppressive regimen is most efficacious for different categories of LSCD or graft types. Evidence-based guidelines for systemic immunosuppression in limbal allograft therapy would benefit from randomized controlled and/or additional prospective studies. Long-term immunosuppression would benefit from close collaboration between ophthalmologists and transplant specialists to individualize treatments.

Validity and Reliability of a Novel Handheld Osmolarity System for Measurement of a National Institute of Standards Traceable Solution.

PURPOSE: To evaluate the validity and reliability of a novel handheld osmolarity system (I-PEN Osmolarity System; I-MED Pharma Inc, Dollard-des-Ormeaux, Quebec, Canada) for measurement of the osmolarity of a National Institute of Standards and Technology (NIST) traceable solution at a variety of ambient temperatures. METHODS: A total of 65 measurements of an NIST solution with a verified osmolarity of 290 ± 2 mOsmol/L were taken using 3 separate handheld osmolarity systems, 65 unique single-use sensors (SUSs) from 3 different lots, and 2 adaptors. Mean values were calculated using the device, SUS, and adaptor. Measurements were taken using a handheld osmolarity system, an adaptor, and 56 individual SUSs at 6 different ambient temperatures ranging from 17.7 to 26.5°C. RESULTS: Overall, the mean osmolarity measured was 294.06 mOsmol/L (SD ±2.29; percent coefficient of variation 0.78), ranging from 286.60 to 298.18 mOsmol/L. This fell within a prespecified acceptable variability of ±4 mOsmol/L (SD ±7). Mean values did not vary across devices, adaptors, or single-use sensors used. Mean osmolarity measurements increased with rising ambient temperatures, with an R = 0.88. The temperature correction factor was calculated to be 2.01 mOsmol/L per °C. CONCLUSIONS: The osmolarity system reliably and accurately measured the osmolarity of an NIST solution in a laboratory setting, using an adaptor to correct for differences in resistance between a laboratory NIST solution measurement and direct measurements on the palpebral conjunctiva of the eyelid. The handheld osmolarity system represents a rapid and accurate instrument for measurement of tear osmolarity in a simulated testing setting.

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.

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.

Simple Preoperative Ink Test as a Novel Adjunct to Intrastromal Keratopigmentation for Post-laser Peripheral Iridotomy Dysphotopsias.

PURPOSE: To describe a simple preoperative ink test as a novel adjunct to intrastromal keratopigmentation for post-laser peripheral iridotomy (LPI) dysphotopsias. METHODS: A surgical marking pen is applied to the area over a peripheral iridotomy before intrastromal keratopigmentation. The patient can then assess whether there is any improvement in their symptoms of dysphotopsias. Manual intrastromal keratopigmentation can then be performed using a crescent blade into the clear cornea at 50% depth and tunneled centrally to create a pocket ensuring that the peripheral iridotomy is fully occluded. The crescent blade is coated with an alcohol-based commercially available black tattoo pigment, and the pocket is filled. RESULTS: We have used the preoperative ink marker test on 5 eyes in patients with post-LPI (4 temporal and 1 superior) dysphotopsias before performing intrastromal keratopigmentation, with good patient satisfaction. Patients report immediate symptomatic relief after the procedure. This ink marking technique can also be extended to help identify which iris defect is symptomatic in patients with multiple iris defects. CONCLUSIONS: The preoperative ink test before intrastromal keratopigmentation is a novel adjunct to the treatment of post-LPI dysphotopsias.

Comparison of Femtosecond Laser-Enabled Descemetorhexis and Manual Descemetorhexis in Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To introduce a novel method to perform descemetorhexis in Descemet membrane endothelial keratoplasty (DMEK) using the femtosecond laser and to compare it with Descemet membrane endothelial keratoplasty performed with manual descemetorhexis (M-DMEK). METHODS: A retrospective medical chart review of 2 groups of patients who underwent DMEK surgery combined with cataract surgery secondary to Fuchs corneal endothelial dystrophy and cataract: 17 patients underwent femtosecond laser-enabled descemetorhexis Descemet membrane endothelial keratoplasty (FE-DMEK) and 89 patients underwent DMEK surgery with M-DMEK. Best spectacle-corrected visual acuity, endothelial cell density (ECD), graft detachment rate, and complications were compared. RESULTS: Average age of the 106 patients (64 women and 42 men) was 68 ± 11 years. Postoperative best spectacle-corrected visual acuity was 0.19 ± 0.13 logarithm of the minimum angle of resolution in the FE-DMEK group and 0.35 ± 0.48 logarithm of the minimum angle of resolution in the M-DMEK group (P = 0.218). One day after surgery, there were no significant graft detachments in the FE-DMEK group, compared with 20% graft detachment rate in the M-DMEK group (P = 0.041). Rebubbling was performed in 17% of eyes in the M-DMEK group compared with none in the FE-DMEK group (P = 0.066). The mean endothelial cell count in the FE-DMEK and M-DMEK groups at 6 months after surgery were 2105 ± 285 cells per square millimeter (24% cells loss) and 1990 ± 600 cells per square millimeter (29% cells loss), respectively (P = 0.579). CONCLUSIONS: FE-DMEK shows efficacy similar to that of M-DMEK with apparently less graft detachment and reduced need for rebubbling.

Randomized, masked, in vitro comparison of three commercially available tear film osmometers.

PURPOSE: The purpose of this study was to compare the precision and accuracy of commercially available tear film osmometers. METHODS: Contrived tear solution target values representing the physiological range of tear osmolarity (normal eyes 297 mOsm/L, moderately dry eyes 342 mOsm/L, and severe dry eyes 383 mOsm/L) were constructed using a mix of mono- and divalent electrolytes, metabolites, serum albumin, and pH balanced to 7.4. Solution values were randomized and masked from the investigators during testing. Osmometers (Wescor 5520 Vapro Pressure Osmometer: device A, TearLab Osmolarity System: device B, and i-Med Pharma i-Pen: device C) were calibrated according to manufacturer instructions. Each level was tested 64× on each osmometer across two sites. Accuracy was reported as a correlation coefficient against expected linear dilutions, precision was calculated as percent coefficient of variation. RESULTS: Device A reported a correlation with known solutions of r2=0.98, with averages of 305.6±4.0, 352.2±5.5, and 389.8±4.0 mOsm/L, and coefficient of variations (CVs) of 1.3%, 1.6%, and 1.0%, respectively. Device B reported an r2=0.96, with averages of 300.6±3.7, 341.4±7.9, and 376.8±5.1 mOsm/L, and CVs of 1.2%, 2.3%, and 1.4%, respectively. Device C reported an r2=0.03, with averages of 336.4±21.5, 342.0±20.7, and 345.7±22.0 mOsm/L, and CVs of 6.4%, 6.1%, and 6.4%, respectively. CONCLUSION: In this randomized, masked, in vitro study, device A and device B had significantly better accuracy and precision in measuring osmolarity of contrived tear solutions of known target values compared to device C. Device C showed insufficient performance to accurately and precisely delineate osmolarity levels in the physiological range. Furthermore, in vivo studies would be required to compare performance in human subjects.

Enhancing Descemet Membrane Endothelial Keratoplasty in Postvitrectomy Eyes With the Use of Pars Plana Infusion.

PURPOSE: To present a modified surgical technique to perform Descemet membrane endothelial keratoplasty (DMEK) in previously vitrectomized eyes and to analyze its safety and efficacy. METHODS: A retrospective analysis of previously vitrectomized eyes that underwent DMEK at Toronto Western Hospital was performed. The modified DMEK technique that was used included placement of a posterior pars plana infusion to reduce fluctuations in the anterior chamber depth and its excessive deepening. RESULTS: Twelve eyes of 12 patients (5 females and 7 males) aged 65.3 ± 21.5 years were included. Mean best-corrected visual acuity improved significantly from 1.72 ± 0.62 logMAR (mean Snellen ∼20/1040) preoperatively to 1.01 ± 0.64 logMAR (mean Snellen ∼20/200) at 6 months postoperatively (P = 0.017). Mean donor endothelial cell density was 2658 ± 229 cells/mm preoperatively and 1732 ± 454 cells/mm at 6 months after the procedure (mean percentage cell loss of 31.8%) (P = 0.046). There were no significant intraoperative complications, and no graft failures. One eye had graft detachment, which resolved after 2 rebubbling procedures. One eye had retinal detachment, which was corrected surgically. CONCLUSIONS: The use of posterior pars plana infusion in previously vitrectomized eyes stabilizes the anterior segment during DMEK, allowing for performance of DMEK surgery, and can potentially reduce intraoperative and postoperative complications.

Spontaneous hyphaema secondary to bleeding from an iris vascular tuft in a patient with a supratherapeutic International normalised ratio: case report.

BACKGROUND: Iris vascular tufts are rare iris stromal vascular hamartomas. Patients with iris vascular tufts generally remain asymptomatic until presenting with a spontaneous hyphaema or with mild intraoperative pupil margin haemorrhage during anterior segment surgery. This is the first reported case of spontaneous hyphaema from iris vascular tuft related to a documented supratherapeutic International Normalised Ratio as a predisposing factor. At 86 years of age, this patient also represents the oldest documented first occurrence of bleeding from an iris vascular tuft. CASE PRESENTATION: An 86 year old Caucasian lady presented with sudden and persisting loss of vision in her right eye, ocular pain and vomiting. She had a supratherapeutic International Normalised Ratio of 3.9 related to Warfarin use. Her intraocular pressure in the right eye was raised at 55 mmHg, with a 1.6 mm hyphaema and multiple iris vascular tufts visible around the entire pupil. CONCLUSION: The present case highlights the risk of anticoagulation therapy as a predisposing factor for spontaneous hyphaema and adds to the management considerations for this condition. It also demonstrates the need for Ophthalmologists to be aware of iris vascular tufts as a cause for spontaneous hyphaema, independent of age and systemic associations.

Ocular pigmentation associated with clozapine.

A 55-year-old woman who was treated with long-term, high-dose clozapine for schizophrenia presented with bilateral decreased visual acuity. She had pigmentary changes affecting the cornea and the retina, as well as stellate cataract. Chlorpromazine use is known to produce similar changes, but this is the first report to our knowledge of pigmentation associated with clozapine use.