A new knotless technique for combined transscleral fixation of artificial iris, posterior chamber intraocular lens, and penetrating keratoplasty.

PURPOSE: To present a new surgical technique for treating corneal opacity and aniridia with aphakia and the results in a small consecutive case series. METHODS: A three-piece acrylic intraocular lens (IOL) was attached to a customized silicone iris prosthesis and fixed with three 10-0 polypropylene sutures in a knotless technique using Z-sutures after trephination of the recipient cornea. The medical records of all consecutive patients who had received a keratoplasty and an implantation of an artificial iris and IOL were reviewed. RESULTS: Five eyes of five patients were included in the analysis. The mean age of the patients was 46.2 years and the mean follow-up was 24.6 months. The mean best-corrected visual acuity improved from 1.36 logMAR before surgery to 0.78 logMAR after surgery during the follow-up. At the last follow-up visit, the artificial iris-IOL complex was well centered with good positioning in all cases. CONCLUSIONS: Management of post-traumatic aniridia combined with aphakia and corneal scars or graft failure by haptic fixation of a foldable IOL on an artificial iris combined with a simultaneous keratoplasty appears to be a promising approach, which allows to correct a complex lesion with a less traumatic and faster procedure.

Effectiveness of curvilinear approach in dissection of Descemet's membrane: first 500 cases - factors influencing graft preparation.

PURPOSE: To confirm the reproducibility of manual graft preparation using curvilinear forceps and evaluate the incidence and type of structural abnormalities of Descemet's membrane (DM) preventing successful grafts preparation. METHODS: Five hundred corneo-scleral buttons were prepared. Factors such as endothelial cell number before preparation, donor age, post-mortem time, time in culture, pigmentation of the trabecular meshwork and preparation characteristics of the fellow eye were analysed. According to the preparation characteristics, three groups were formed: A, uncomplicated; B, complicated preparation with stripping from the contralateral side; and C, failure of preparation. Three failed grafts were examined by transmission electron microscopy (TEM). RESULTS: Using curvilinear forceps, manual separation of DM was achieved without any adverse effects in 457 of 500 corneas (91.4%). In 32 corneas (6.4%) with micro-tears during preparation, stripping from the opposite side was possible. However, 11 of the 500 corneas (2.2%) showed extremely strong adhesion leading to multiple tears of DM and preventing successful preparation of the graft. Endothelial cell number, donor age, post-mortem time, time in culture and pigmentation of the trabecular meshwork showed no significant correlation with failure to successfully obtain a DM graft. Complicated graft preparations of one eye showed a highly significant correlation with complicated graft preparations in the fellow eye. TEM analysis of failed grafts showed abnormal invasion of stromal parts into the DM, cell accumulation and pigmentation in the DM plane. CONCLUSION: Using curvilinear forceps for dissecting of the graft shows valid and reproducible results in the vast majority (97.8%) of donor corneas.

Factors influencing the contamination rates of the conjunctival swabs and organ culture media of human donor eyes.

This study assessed the influence of donor, environmental, and logistical factors on the contamination rates of the conjunctival swabs and organ culture media of human donor eyes.In total, 1008 conjunctival swabs and 418 organ culture media samples from 504 consecutive human donor eyes were analyzed. Cross-tabulation, chi-squared tests, and Fisher's exact tests were used to assess the influence of the different factors on the contamination rates of the conjunctival swabs and organ culture media.The overall contamination rates were 28.4% for the conjunctival swabs and 1.0% for the organ culture media. A prolonged time between death and the conjunctival swab collection was associated with an increased conjunctival swab contamination rate [odds ratio (OR) = 1.9, 95% confidence interval (CI) = 1.2-3.0, P = .007]. The highest conjunctival swab contamination rate was found in the corneas procured in external institutions (outside the university hospital) (44.1%, OR = 3.6, 95%CI = 1.5-8.4, P = .003). Hospitalization times of 2 to 7 days prior to death were associated with an increased conjunctival swab contamination risk (OR = 2.6, 95%CI = 1.1-5.8, P = .021). However, the sex, age, cause of donor death, differentiation between septic and aseptic donors, differentiation between heart-beating brain-dead multiorgan donors and cadaveric donors, a warmer mean monthly temperature, and death to corneoscleral disc excision time did not significantly increase the conjunctival swab contamination risk. In addition, none of these factors affected the organ culture media contamination risk. Moreover, a positive conjunctival swab did not significantly increase the media contamination risk (P = .08). Surprisingly, the microorganisms causing media contamination were present at 50% of the amount detected on the conjunctival surface of the respective donor eye.A prolonged time between death and the conjunctival swab collection, a hospitalization time of 2 to 7 days prior to death, and corneal collection outside the university hospital seemed to be the main factors responsible for an increased conjunctival swab contamination risk. In addition, our investigation illustrated that a positive conjunctival swab is not a strong indicator for organ culture media contamination. Critical discussion is necessary regarding the validity of conjunctival swabs as prognostic parameters for organ culture media contamination.

Novel Technique for Improving Graft Unfolding in Vitrectomized Eyes Using a Temporary Diaphragm in Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To describe a new surgical technique for performing Descemet membrane endothelial keratoplasty (DMEK) using a temporary hydrophilic methacrylate sheet in the anterior chamber in cases of previous vitrectomy with complete removal of the vitreous body. METHODS: Medical records were reviewed for baseline and follow-up best spectacle-corrected visual acuity, endothelial cell count, and indication for DMEK using a temporary hydrophilic methacrylate sheet. Operative notes were analyzed in all cases to identify any specific intraoperative event. RESULTS: Seven eyes of 7 patients were included in this analysis. Mean age was 65.7 ± 18.2 years, and the mean follow-up duration was 11.5 months. All 7 patients had previously received pars plana vitrectomy with complete vitreous removal. All patients were pseudophakic. For 5 patients, it was their first DMEK surgery and 2 patients had DMEK surgery for a second time, due to a failed outcome in previous surgery. Best spectacle-corrected visual acuity improved from 1.5 ± 0.5 logMAR before surgery to 0.76 ± 0.37 logMAR after surgery during follow-up (P < 0.001). The mean endothelial cell count was 2442 ± 304 cells/mm and decreased to 1484 ± 279 cells/mm during follow-up (P < 0.001). No complications were observed in any of the cases at the unfolding stage using this method. All grafts remained clear at the last follow-up visit. CONCLUSIONS: This modified approach of DMEK surgery, using a temporary hydrophilic methacrylate sheet for flattening the anterior chamber and facilitating graft unfolding, could help overcome possible complications of DMEK in completely vitrectomized eyes.

Allelic Expression Imbalance in the Human Retinal Transcriptome and Potential Impact on Inherited Retinal Diseases.

Inherited retinal diseases (IRDs) are often associated with variable clinical expressivity (VE) and incomplete penetrance (IP). Underlying mechanisms may include environmental, epigenetic, and genetic factors. Cis-acting expression quantitative trait loci (cis-eQTLs) can be implicated in the regulation of genes by favoring or hampering the expression of one allele over the other. Thus, the presence of such loci elicits allelic expression imbalance (AEI) that can be traced by massive parallel sequencing techniques. In this study, we performed an AEI analysis on RNA-sequencing (RNA-seq) data, from 52 healthy retina donors, that identified 194 imbalanced single nucleotide polymorphisms(SNPs) in 67 IRD genes. Focusing on SNPs displaying AEI at a frequency higher than 10%, we found evidence of AEI in several IRD genes regularly associated with IP and VE (BEST1, RP1, PROM1, and PRPH2). Based on these SNPs commonly undergoing AEI, we performed pyrosequencing in an independent sample set of 17 healthy retina donors in order to confirm our findings. Indeed, we were able to validate CDHR1, BEST1, and PROM1 to be subjected to cis-acting regulation. With this work, we aim to shed light on differentially expressed alleles in the human retina transcriptome that, in the context of autosomal dominant IRD cases, could help to explain IP or VE.

Effect of Organ Scandal on Corneal Donation Rate and Organ Donors at a German University Hospital.

BACKGROUND The purpose of this study was to assess the effect of an organ transplantation scandal on the rate of corneal donations and organ donors at the University Hospital Tübingen. MATERIAL AND METHODS Data from all hospital deaths from January 2012 to December 2013 were analyzed retrospectively. Each deceased patient was considered as a potential corneal donor. The corneal donor procurement was handled by an ophthalmic resident on a full-time basis with standard used unchanged set of procedures. Each patient who died due to cerebral complications was considered as a potential organ donor. During the two-year period, a German transplantation scandal occurred at the end of 2012 and received worldwide attention. The rates of corneal donation and organ donation in 2012 and 2013 were examined and evaluated. RESULTS Among the 1685 deceased patients, approval for corneal donation was received in 220 cases (13.1%): 124 cases (15.0%) in 2012 and 96 cases (11.2%) in 2013. This corresponds to a decline of 23%. The leading causes of nonfulfillment of corneal donations were refusal to donation: 401 cases (48.4%) in 2012 and 445 cases (52.0%) in 2013; and medical contraindications: 201 cases (24.2%) in 2012 and 212 cases (24.8%) in 2013. During the two-year period, consent for organ donation was obtained in 25 cases (1.5%): 15 cases (1.8%) in 2012 and 10 cases (1.2%) in 2013. The number of realized organ donors was 20 cases (1.2%): 12 cases (1.4%) in 2012 and 8 cases (0.9%) in 2013. This corresponds to a decline of 33%. CONCLUSIONS After a transplantation scandal, the number of realized corneal donors and realized organ donors decreased significantly. It seems that increasing professional performance is very important to gaining trust inside and outside the hospital and improving corneal and organ donation rate.

Factors influencing the contamination rate of human organ-cultured corneas.

PURPOSE: To assess the influence of donor, environment and storage factors on the contamination rate of organ-cultured corneas, to consider the microbiological species causing corneal contamination and to investigate the corresponding sensitivities. METHODS: Data from 1340 consecutive donor corneas were analysed retrospectively. Logistic regression analysis was used to assess the influence of different factors on the contamination rate of organ-cultured corneas for transplantation. RESULTS: The mean annual contamination rate was 1.8 ± 0.4% (range: 1.3-2.1%); 50% contaminations were of fungal origin with exclusively Candida species, and 50% contaminations were of bacterial origin with Staphylococcus species being predominant. The cause of donor death including infection and multiple organ dysfunction syndrome increased the risk of bacterial or fungal contamination during organ culture (p = 0.007 and p = 0.014, respectively). Differentiating between septic and aseptic donors showed an increased risk of contamination for septic donors (p = 0.0020). Mean monthly temperature including warmer months increased the risk of contamination significantly (p = 0.0031). Sex, donor age, death to enucleation, death to corneoscleral disc excision and storage time did not increase the risk of contamination significantly. CONCLUSION: The genesis of microbial contamination in organ-cultured donor corneas seems to be multifactorial. The main source of fungal or bacterial contamination could be resident species from the skin flora. The rate of microbial contamination in organ-cultured donor corneas seems to be dependent on the cause of donor death and mean monthly temperature.

Evaluation of Factors Limiting Corneal Donation.

BACKGROUND This study aimed to investigate factors limiting corneal donation at the University Hospital Tübingen. MATERIAL AND METHODS We retrospectively studied all hospital deaths from January 2012 to December 2015, considering each deceased patient as a potential corneal donor. During this period an ophthalmic resident managed corneal donor procurement on a full-time basis. Various factors limiting corneal donation were examined. RESULTS Among the 3412 deaths, 2937 (86.1%) displayed nonfulfillment of corneal donation. Consent for corneal donation was obtained in 475 cases (13.9%). The mean annual corneal donation rate was 13.9 donors per 100 deaths (range: 11.2-17.8). The leading causes of nonfulfillment of corneal donations were refusal to donate (49.8%, 1698 cases) and medical contraindications (23.6%, 805 cases). After next-of-kin interview of 2173 potential donors (109 potential donors were excluded because of logistical problems), willingness to participate in corneal donation was present in 475 cases (21.9%), whereas in 1698 cases (78.1%) corneal donation was refused. CONCLUSIONS Our study showed refusal to donate is the most important factor limiting corneal donation. It seems that increasing the knowledge of people about corneal donation through public education and media are necessary to address the corneal shortage.

Air Bubble-Induced High Intraocular Pressure After Descemet Membrane Endothelial Keratoplasty.

PURPOSE: To investigate the incidence and risk factors of pupillary block caused by an air bubble in the anterior chamber in the early postoperative period after Descemet membrane endothelial keratoplasty (DMEK). METHODS: A retrospective review was conducted in 306 eyes that underwent DMEK from September 2009 through October 2014 at the Tübingen Eye Hospital. Intraocular pressure (IOP) elevation was defined as a spike above 30 mm Hg. In the first 190 eyes, an intraoperative peripheral iridectomy was performed at the 12-o'clock position and in the other 116 eyes at the 6-o'clock position. If possible, reasons for IOP elevation were identified. For all eyes, preoperative and postoperative slit-lamp examinations and IOP measurements were performed. RESULTS: Overall, 30 eyes (9.8%) showed a postoperative IOP elevation within the first postoperative day. The incidence of IOP elevation was 13.9% (5/36) in the triple DMEK group, and 2 of 5 phakic eyes (40%) developed an air bubble-induced IOP elevation. All eyes presented with a de novo IOP elevation, associated in 25 patients with pupillary block from air anterior to iris and in 5 patients with angle closure from air migration posterior to the iris. All of them had an iridectomy at the 12-o'clock position. CONCLUSIONS: A postoperative pupillary block with IOP elevation caused by the residual intraoperative air bubble may be an important complication that could be avoided by close and frequent observations, especially in the first postoperative hours and by an inferior peripheral iridectomy and an air bubble with a volume of ≤80% of the anterior chamber.

Hypothermia Promotes Survival of Ischemic Retinal Ganglion Cells.

PURPOSE: Ischemic stroke in retinal arteries leads to death of neural tissue and ultimately to blindness. The retina is known to die within 4 hours after onset of ischemia. It is debated whether hypothermia might increase the time window for medical treatment and thereby the chance of recovering sight. In order to characterize the time course of cell death during ischemia and potential beneficial effects of hypothermia in more detail, we investigated the survival of ganglion cells in ischemic pig and human retina as a function of time and temperature. METHODS: Eyes were obtained from minipigs and from human donors post mortem. Enucleated minipig eyes were stored for defined durations at three different temperatures (37 °C, 21 °C, and 4 °C). In order to assess the viability of the tissue, we measured ganglion cell activity (spiking) with multielectrode arrays. RESULTS: Minipig retinal ganglion cell function was severely compromised after 2 hours of ischemia at body temperature. After 4 hours, ganglion cells did not fire action potentials anymore. However, at 21 °C, ganglion cell activity was maintained under ischemic conditions for up to 12 hours, and for at least 50 hours at 4 °C. In postmortem human retina, we recorded ganglion cell activity in retinas received up to 27 hours after death. CONCLUSIONS: Our results demonstrate that hypothermia greatly increases survival of retinal ganglion cells exposed to ischemia. These results might be relevant for the future treatment of retinal ischemia.

Customized humanoptics silicone iris prosthesis in eyes with posttraumatic iris loss: outcomes and complications.

PURPOSE: Posttraumatic partial or total iris defects often cause significant debilitating glare, photophobia, decreased vision and cosmetic problems. Currently, the best cosmetic results can be obtained with a customized silicone iris prosthesis. However, little is known about the functional results and the rate of complication if this type of iris prosthesis is implanted into severely traumatized eyes. The aim of this study is to analyse the functional and cosmetic outcomes as well as complications after Artificial Iris implantation. METHODS: A consecutive series of 34 patients who received a customized silicone iris prosthesis after severe globe injury with total or sub-total iris loss was analysed retrospectively. Additionally, patients were interviewed regarding change in subjective complaints. RESULTS: Median follow-up was 24 months (range 12.0-48.8). Mean visual acuity prior to Artificial Iris implantation was 1.1 logMAR (range 0.3-2.6). Five patients (15%) had pre-existing glaucoma and eight patients (24%) had pre-existing hypotony. Visual acuity 12 months after surgery was 1.4 logMAR (range 0.2-2.6). Complications included newly diagnosed glaucoma in three eyes (9%) and hypotony in three eyes (9%), persisting intraocular inflammation or macular oedema in seven patients (21%), and corneal endothelial decompensation requiring corneal transplantation in six patients (18%). Patients' satisfaction increased by reducing glare and enhanced cosmetic appearance. CONCLUSION: The customized silicone iris prosthesis is an individualized treatment approach with appealing cosmetic results. Therefore, especially traumatized eyes with highly different posttraumatic conditions could benefit. However, in some patients, the implantation of this device may cause an increase of intraocular pressure, corneal endothelial decompensation or persisting inflammation.

Impact of the radius of the injector system on the cell viability in descemet membrane endothelial keratoplasty: an ex vivo experimental study.

PURPOSE: To evaluate the impact of the radius of the injector system on the viability of the endothelial cells in Descemet membrane endothelial keratoplasty (DMEK). METHODS: Descemet membranes (DMs) of 30 corneoscleral rims were used in a paired design and divided into three groups (A, B, C). The right corneas were used as control (without shooting through the injector after DM preparation) and the left cornea for simulation of the implantation step (shooting through a glass injector of different radii). The injector in Group A had a diameter of 0.5 mm, group B 0.9 mm and group C 1.4 mm. Prior to preparation, endothelial cell count was measured and endothelial cell quality assessed. Quantification of potential damage was achieved by staining with a viability bioassay (calcein acetoxymethyl and ethidium homodimer-1) and DAPI. Apoptosis was evaluated by TUNEL (terminal dUTP nick-end labelling) staining. RESULTS: The average percentage of the endothelial cell death ratios was 4.9 ± 3.3% in group A (n = 5), 3.7 ± 3.7% in group B (n = 5) and 3.9 ± 3.6% in group C (n = 5) with no significant difference compared to the control. The average percentage of apoptotic endothelial cells was 0.05 ± 0.05%, 0.60 ± 0.53% and 0.15 ± 0.26% in groups A, B and C, respectively, with no significant difference compared to the control. CONCLUSIONS: Prepared grafts for transplantation in DMEK procedures may be injected through a smaller sized injector system of up to 0.5 mm with no significant increase in cell loss. Clinical studies are necessary to draw a final conclusion.

Iron accumulation in Bruch's membrane and melanosomes of donor eyes with age-related macular degeneration.

Iron (Fe) accumulation in cytoplasmic storages of the retina and retinal pigment epithelium (RPE) with age has been reported to be a contributing factor to the onset and progression of Age-related Macular Degeneration (AMD). This work investigated whether iron can also be stored in specialized metal-binding melanosomes of the RPE and choroid and in age pigments of the RPE (lipofuscin and melanolipofuscin). As accumulation of debris in Bruch's membrane is an additional hallmark of AMD, the elemental composition of Bruch's membrane was also investigated. Perimacular sections of the retina-choroid complex of six eyes of AMD donors and of seven age-matched healthy controls were investigated using Analytical Electron Microscopy (AEM). The melanosomes of the RPE and choroidal melanocytes of all AMD donors contained about two times higher iron mole fractions (0.06-0.07 at%) compared to the controls, which showed only minor iron mole fractions at or below the detection limit of 0.02 at%. Only melanosomes that contained iron, showed also significant lead peaks (both AMD and control about 0.08 at%). In addition, the electron-dense part of melanolipofuscin granules in the RPE accumulated iron and lead, both for control and AMD donors. Iron in lipofuscin was below the detection limit. The elastic layer of Bruch's membrane of all AMD donors also contained significantly higher iron mole fractions compared to controls (about 0.08 at% Fe), predominantly in areas that were also rich in calcium (Ca) and phosphorus (P), suggesting calcification. Indeed, five of the six AMD donors but only one of the seven controls showed nanocrystalline hydroxyapatite calcifications. Note that such nanocrystalline material can only be detected in EM samples without heavy metal (osmiumtetroxide, uranylacetate) staining. In conclusion, iron accumulation in melanosomal storages and within calcified Bruch's membrane is more pronounced in donors suffering from AMD compared to age-matched controls. This work underlines the common hypothesis that heavy metal homeostasis plays an important role in age-related neuropathy.

Cytotoxic Effect of Voriconazole on Human Corneal Epithelial Cells.

BACKGROUND: To assess the cytotoxic properties of voriconazole and sulfobutylether-ß-cyclodextrin (SBECD) on cultured primary human corneal epithelial cells. METHODS: Human corneal epithelial cells were cultured and exposed to various concentrations of SBECD (0.016-32 mg/ml) and voriconazole (0.001-2 mg/ml). Cellular cytotoxicity of SBECD and voriconazole on human corneal epithelial cells was evaluated using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide test and the LIVE/DEAD Viability/Cytotoxicity Assay with fluorescence microscopy analysis. Cell damage was assessed with phase-contrast microscopy after 24 h of exposure to SBECD and voriconazole. RESULTS: The cytotoxicity tests and the morphological characteristic demonstrated the dose-dependent toxic effect of SBECD and voriconazole on human corneal epithelial cells. No corneal epithelial cytotoxicity was observed below the concentration of 0.08 and 0.025 mg/ml after 24-hour exposure to SBECD and voriconazole, respectively. CONCLUSIONS: The results of the study reveal the dose-dependent cytotoxic effect of SBECD and voriconazole on cultured human corneal epithelial cells. Therefore, voriconazole eye drops should be used cautiously in the treatment of fungal corneal ulcers.

Switching intravitreal anti-VEGF treatment in neovascular age-related macular degeneration.

PURPOSE: To compare the outcomes after switching between bevacizumab and ranibizumab therapy due to poor treatment effect in neovascular age-related macular degeneration (AMD). METHODS: This is a retrospective review of patients with neovascular AMD with first treatment using intravitreal bevacizumab (group 1) or ranibizumab (group 2) who switched to the other drug due to poor treatment effect. Primary outcome measures were change in mean best-corrected visual acuity (BCVA) and mean central retinal thickness (CRT) at 1 year and last visit. RESULTS: Eighty-seven eyes met the inclusion criteria. In group 1 (43 eyes), the mean BCVA decreased from 20/94 to 20/100 at 1 year after being switched (p = 0.573) and to 20/150 (p = 0.015) at final visit (mean 29.2 months, range 12-53). In group 2 (44 eyes), mean BCVA decreased from 20/72 to 20/90 (p = 0.401) and 20/100 (p = 0.081) at 1 year after switch and at final visit (mean 20.1 months, range 10-40), respectively. The mean CRT at switch, 1 year after switch, and at final visit were 344.4 ± 140 µm (mean ± SD), 286.26 ± 155 µm (p = 0.019), and 290.58 ± 196 µm (p = 0.009) in group 1 and 329.36 ± 144 µm, 302.0 ± 179 µm (p = 0.215), and 309.5 ± 220 µm (p = 0.154) in group 2, respectively. CONCLUSIONS: The mean BCVA decreased over time in both groups; however, nearly 30% of the eyes in each group showed vision improvement after switching. Mean CRT decreased in both groups, which was more pronounced after being switched from bevacizumab to ranibizumab. In neovascular AMD, a switch between ranibizumab and bevacizumab can be considered as a further therapy option if poor treatment effect is seen with the initial therapy.

Descemet membrane endothelial keratoplasty in vitrectomized eyes: clinical results.

PURPOSE: The aim of this study was to evaluate clinical outcomes of Descemet membrane endothelial keratoplasty (DMEK) in vitrectomized eyes. METHODS: Medical records were reviewed for demographics, baseline and follow-up best spectacle-corrected visual acuities (BCVAs), endothelial cell densities, and indication for DMEK. Operative notes were analyzed to identify any specific intraoperative event. RESULTS: A total of 281 DMEK cases were reviewed. Twenty cases were considered eligible for the study. Seven eyes had a history of anterior vitrectomy, and 13 eyes had a history of complete removal of the vitreous body. Ages ranged from 37 to 78 years (mean, 62.9 years) and mean follow-up after DMEK was 11.2 months (range, 3-29 months). The preoperative mean BCVA was 1.4 ± 0.5 logarithm of minimum angle of resolution (logMAR) and increased to 1.0 ± 0.5 logMAR after 4 weeks (P = 0.0290). After 6-month and 12-month follow-up, BCVA was 0.8 ± 0.6 logMAR (P = 0.0055) and 0.6 ± 0.3 logMAR (P = 0.0001), respectively. All cases had ocular comorbidities affecting the BCVA. In 13 cases, significant intraoperative complications were experienced. In the immediate postoperative period, iatrogenic primary graft failure was reported in 2 eyes (2/20). In 4 eyes, late graft failure was observed. Two eyes had exacerbation of preexisting glaucoma. Mean preoperative endothelial cell density was 2301 ± 159 cells per square millimeter; postoperative follow-up visits at 6 and 12 months showed a decrease to 1398 ± 161 cells per square millimeter and 1241 ± 155 cells per square millimeter, respectively. CONCLUSIONS: DMEK seems to be successful in restoring visual acuity even in vitrectomized eyes. Nevertheless, the overall complication rate was higher than that in standard DMEK.

Choriocapillaris breakdown precedes retinal degeneration in age-related macular degeneration.

This work presents a combined light and electron microscopical approach to investigate the initial breakdown of the retinal pigment epithelium (RPE) and choriocapillaris (CC) in age-related macular degeneration (AMD). Perimacular sections of 12 dry and wet AMD eyes (82 ± 15 years) and 7 age-matched controls (75 ± 10 years) without retinal pathology were investigated. Disease progression was classified into 5 stages of retinal degeneration to investigate the concurrent CC breakdown. Special emphasis was laid on transitions where intact CC-RPE-retina complexes went over into highly atrophied areas. AMD sections showed elevated loss of photoreceptors, RPE and CC (p < 0.01), and thickened Bruch's membrane with increased basal laminar and linear deposits compared with controls. Up to 27% of the CC was lost in controls although RPE and retina were still intact. This primary loss of CC further increased with AMD (up to 100%). The data implicate that CC breakdown already occurs during normal aging and precedes degeneration of the RPE and retina with AMD, defining AMD as a vascular disease. Particular attention should be given to the investigation of early AMD stages and transitional stages to the late stage that reveal a possible sequence of degenerative steps with aging and AMD.

Descemet membrane endothelial keratoplasty in cases with existing scleral-sutured and iris-sutured intraocular lenses.

BACKGROUND: To report two cases of Descemet Membrane Endothelial Keratoplasty (DMEK) in patients with existing scleral-fixated and iris-fixated intraocular lenses (sf-IOL and if-IOL, respectively). CASE PRESENTATION: DMEK procedures were performed on a 49-year-old woman with a pre-existing sf-IOL (case 1) and a 69-year-old woman with a pre-existing if-IOL (case 2) in order to treat secondary corneal edema due to pseudophakic bullous keratopathy. Visual acuity, refractive error, intraocular pressure, slit lamp examination, pachymetry measurements and endothelial cell density (ECD) were considered and repeated during follow-ups.Both cases had no intraoperative complications. At postoperative day 1 graft centration and complete attachment were noted. The IOL positions were unchanged in comparison to their preoperative positions. In case 1, visual acuity improved from 1/15 at 1 meter preoperative to 20/200 within one week and to 20/63 within 12 weeks of follow up. In case 2, visual acuity improved from counting fingers at 1 meter preoperative to 20/200 within one week and to 20/100 within 12 weeks of follow-up. In case 2 a partial graft dislocation was observed at postoperative day twenty. Complete graft re-apposition was achieved by rebubbling procedure performed with intracameral air injection. CONCLUSIONS: DMEK surgery in the treatment of pseudophakic bullous keratopathy in the presence of sf-IOL and if-IOL can successfully be performed. These eyes are at increased risk of IOL dislocation into the vitreous cavity during DMEK surgery.