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Objective: To investigate indications and surgical procedures of keratoplasty in a tertiary comprehensive hospital in northern part of China over a 20-year period. Methods: All patients undergoing keratoplasty between January 1, 2002 to December 31, 2021 in a tertiary comprehensive hospital in northern part of China were retrospectively reviewed. The annual proportion of keratoplasty indications and surgical procedures was recorded and analyzed. Results: A total of 8266 keratoplasty procedures were included. Leading indications were keratoleukoma (n = 2108, 25.50%), followed by regraft (n = 1453 ,17.58%), corneal endothelial dysfunction (n = 1085, 13.13%), and keratoconus (n = 922,11.15%). A decreasing trend was observed for keratoleukoma (P < 0.01) and an increasing trend for corneal endothelial dysfunction (P < 0.01), regraft (P = 0.012), corneal limbal dermoids (P < 0.01) and congenital corneal opacity (P < 0.01). From 2002 to 2021, the proportion of penetrating keratoplasty (PK) had decreased from 73.95% (2002 to 2006) to 53.49% (2017 to 2021). On contrary, anterior lamellar keratoplasty (ALK) (459–705, 26.05-31.96%, P = 0.034) and endothelial keratoplasty (EK) (0-321, 0.00-14.55%, P < 0.01) became more prevalent from 2002 to 2021. For cases with corneal endothelial dysfunction, EK became the preferred technique (74.72%) in the recent 5 years. Conclusion: Over the past 20 years, keratoleukoma and regraft have been the leading indications for keratoplasty. A noticeable shift in surgical preference from PK to DSAEK and ALK is evident, with key indications for keratoplasty including keratoleukoma, regraft, limbal dermoids, endothelial dysfunction, and keratoconus, respectively. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to investigate the risk factors for glaucoma in patients with keratoconus following keratoplasty and to identify potential factors that could affect post-transplant complications. Methods: A retrospective analysis was conducted on the medical records of 192 keratoconus patients who underwent keratoplasty. Data on treatment history, perioperative information, tissue bank data, postoperative regimens, complications, and infections were collected and analyzed. Statistical analysis was performed to identify risk factors associated with glaucoma and transplant complications. Results: There was a 41.6% incidence of glaucoma (high IOP) (p < 0.001), with the median time to glaucoma development being 314 ± 67 days post-transplant. A significant number of patients required surgical intervention, accounting for 48.05%. Our analysis revealed a 14% graft failure rate. On univariable Cox proportional hazard analysis, the following factors demonstrated statistically significant associations with the risk of glaucoma after transplantation: donor endothelial cell density, the use of a single continuous suture type, and the surgeon (performing the surgery). For many variables, the only factor that remained significant was the surgeon. Among the factors analyzed for risks of failure post-transplantation, significant associations were observed for the donor age, the time from harvest to transplant, and the surgeon. In the multivariable analysis, donor age emerged as a significant predictor of post-transplant complications. Conclusions: Risk factors such as donor endothelial cell density, suture type, surgeon, host and donor size, and host gender were found to increase the risk of developing glaucoma post-keratoplasty. Surgeon type was identified as a significant risk factor, while donor age was predictive of post-transplant complications. [ABSTRACT FROM AUTHOR]

Despite tremendous developments in the field of laboratory testing in transplantation, the rules of eligibility for corneal transplantation still do not include typing of human leukocyte antigens (HLAs) in the donor and recipient or detection of donor-specific antibodies (DSAs) in the patient. The standard use of diagnostic algorithms is due to the cornea belonging to immunologically privileged tissues, which usually determines the success of transplantation of this tissue. A medical problem is posed by patients at high risk of transplant rejection, in whom the immune privilege of the eye is abolished and the risk of transplant failure increases. Critical to the success of transplantation in patients at high risk of corneal rejection may be the selection of an HLA-matched donor and recipient, and the detection of existing and/or de novo emerging DSAs in the patient. Incorporating the assessment of these parameters into routine diagnostics may contribute to establishing immune risk stratification for transplant rejection and effective personalized therapy for patients. [ABSTRACT FROM AUTHOR]

Background: This study aims to evaluate the clinical outcomes and efficacy of a modified tectonic corneoscleral graft (TCG) in patients suffering from devastating corneoscleral infections. Methods: Thirty-eight eyes from 38 patients who underwent the modified TCG were included in this study. The outcomes measured were recurrence rates, best-corrected visual acuity (BCVA), ocular surface stability, postoperative complications, and graft survival. Results: Among the 38 patients, 23 had fungal infections, 9 had bacterial infections and 6 had Pythium insidiosum infections. At the final follow-up, with an average duration of 25.1 ± 8.6 months, the rate of monocular blindness decreased from 100 to 58%. Significant improvements in LogMAR BCVA were observed from preoperative to postoperative measurements (P < 0.001). Thirty-two eyes (84.2%) maintained a stable ocular surface. The survival rate of ocular surface stability was 84.2%±5.9% at one year and 57.7%±9.7% at three years post-surgery. Twenty eyes (52.6%) retained a clear graft, with a survival rate for graft clarity was 81.6%±6.3% at one year and 36.0%±10.8% at three years post-surgery. The incidence of immune rejection was 36.8%. Corneal epithelial defects were observed in ten patients, and choroidal detachment occurred in four patients. No cases of elevated intraocular pressure were detected. Conclusions: The modified TCG is effective in eradicating infections, preserving the eyeball, and maintaining useful vision in cases of devastating corneoscleral infections. Regular use of tacrolimus, timely administration of glucocorticoids, and good patient compliance can help mitigate postoperative challenges. [ABSTRACT FROM AUTHOR]

PurposeMethod(s)ResultsConclusionTo evaluate co-morbid sociomedical conditions affecting corneal donor endothelial cell density and transplant suitability.Corneal donor transplant information was collected from the CorneaGen eye bank between June 1, 2012 and June 30, 2016. A natural language processing algorithm was applied to generate co-morbid sociomedical conditions for each donor. Variables of importance were identified using four machine learning models (random forest, Glmnet, Earth, nnet), for the outcomes of transplant suitability and endothelial cell density. SHAP (SHapley Additive exPlanations) values were generated, with beeswarm and box plots to visualize the contribution of each feature to the models.With a total of 23,522 unique donors, natural language processing generated 30,573 indices, which were reduced to 41 most common co-morbid sociomedical conditions. For transplant suitability, hypertension ranked the top overall variable of importance in two models. Hypertension, chronic obstructive pulmonary disease, history of smoking, and alcohol use appeared consistently in the top variables of importance. By SHAP feature importance, hypertension (0.042), alcohol use (0.017), ventilation of donor (0.011), and history of smoking (0.010) contributed the most to the transplant suitability model. For endothelial cell density, hypertension was the sociomedical condition of highest importance in three models. SHAP scores were highest among the sociomedical conditions of hypertension (0.037), alcohol use (0.013), myocardial infarction (0.012), and history of smoking (0.011).In a large cohort of corneal donor eyes, hypertension was identified as the most common contributor to machine learning models examining sociomedical conditions for corneal donor transplant suitability and endothelial cell density. [ABSTRACT FROM AUTHOR]

Advancements in diagnostic methods and surgical techniques for keratoconus (KC) have increased non-invasive treatment options. Successful surgical planning for KC involves a combination of clinical science, empirical evidence, and surgical expertise. Assessment of disease progression is crucial, and halting the progression should be the focus if it is progressive. While surgeons used to rely on experience alone to decide the surgical method, comparing the network of primary factors, such as visual acuity, across studies can help them choose the most appropriate treatments for each patient and achieve optimal outcomes. Meticulous tabulation methods facilitate interpretation, highlighting the importance of selecting the correct surgical and rehabilitation approach based on each patient's condition and stage of the disease. We detail the outcomes of a comprehensive network meta-analysis comparing the effectiveness of various combined therapeutic refractive treatments for KC at identical stages of the disease, spanning 4 distinct follow-up intervals. Additionally, the comprehensive analysis suggests that for corneas with optimal best corrected visual acuity (BCVA) preoperatively (classified as regular), combining phakic intraocular lenses with intracorneal ring segments (ICRS) and corneal cross-linking (CXL) could offer the best therapeutic approach provided the disease stage does not exceed stage 3. For irregular corneas, although initial follow-ups show a significant difference in BCVA with surface ablation, longer-term follow-ups recommend combining surface ablation with ICRS and CXL, especially at higher stages. [ABSTRACT FROM AUTHOR]

Abstract This study aims to observe the clinical efficacy and safety of rigid gas permeable corneal contact lenses (RGP-CLs) wearing after femtosecond laser-assisted minimally invasive lamellar keratoplasty (FL-MILK) in progressive and advanced keratoconus eyes. Twenty-five patients (27 eyes) fitted with RGP-CLs after FL-MILK were enrolled, and 22 grading-matched keratoconus patients (23 eyes) as a control group. Corneal morphological data, diopter, best corrected vision, corneal endothelium, non-invasive tear film rupture time (NIBUT), corneal perception and comfort questionnaire were analysed before and after wearing RGP-CLs. In the FL-MILK group, the flat K, steep K and Kmax of the corneal anterior surface were decreased by 3.05D, 3.48D and 7.17D respectively after surgery (P = 0.011, 0.004 and 0.007). The central corneal thickness increased by 175.29 μm (P

AIM: To evaluate the efficacy and safety of porcine corneal acellular stromal deep lamellar keratoplasty in the treatment of infectious keratitis.METHODS:Prospective study. A total of 17 patients(17 eyes)with infectious keratitis who failed to receive conservative treatment in our hospital from February 2017 to October 2020 were collected, and porcine corneal acellular stromal deep lamellar keratoplasty was performed using acellular porcine corneal matrix. The postoperative follow-up was 6 mo, and best corrected visual acuity(BCVA), corneal epithelial healing, corneal transparency were observed, and the recurrence of infection and graft rejection were recorded.RESULTS:All patients successfully underwent deep lamellar keratoplasty without intraoperative complications, and there were no cases of loss to follow-up. Postoperative corneal infections were effectively controlled, and BCVA was improved(P

Abstract Background This study aims to evaluate the clinical outcomes and efficacy of a modified tectonic corneoscleral graft (TCG) in patients suffering from devastating corneoscleral infections. Methods Thirty-eight eyes from 38 patients who underwent the modified TCG were included in this study. The outcomes measured were recurrence rates, best-corrected visual acuity (BCVA), ocular surface stability, postoperative complications, and graft survival. Results Among the 38 patients, 23 had fungal infections, 9 had bacterial infections and 6 had Pythium insidiosum infections. At the final follow-up, with an average duration of 25.1 ± 8.6 months, the rate of monocular blindness decreased from 100 to 58%. Significant improvements in LogMAR BCVA were observed from preoperative to postoperative measurements (P

Abstract Background The purpose of the study was to assess visual outcomes, complications, intraocular lens (IOL) stability, and corneal status after sutured scleral-fixated intraocular lens implantation combined with penetrating keratoplasty (PKP). Methods This retrospective single-arm cohort study included patients who underwent PKP and sutured scleral-fixated intraocular lens implantation between 2013 and 2018 at the Dhahran Eye Specialty Hospital. The eyes were examined postoperatively at 1, 3, 6, 12, and 24 months. Corneal status, complications, and IOL status were also evaluated periodically, and the number of eyes with a BCVA of > 20/200 was recorded. Results Twenty-two eyes from 22 patients were included. The median duration of follow-up was 3 (IQR 1.8; 4.4) years. Reasons for surgery were traumatic globe rupture (six eyes, 27.3%), bullous keratopathy (nine eyes, 40.1%), failed previous graft (five eyes, 22.7%), and corneal scarring (two eyes, 9.1%). Twelve (54.5%) eyes showed a BCVA of > 20/200 (non-blind) at 12 months after surgery and only five (22.7%) before surgery. Twelve months after surgery, 13 patients showed an improvement in BCVA in two lines (59.1%), seven remained the same (31.8%), and 2 deteriorated (9.1%). The indication for surgery (p = 0.2) and the stability of the sutured-scleral fixated IOL (p = 0.8) were not associated with an improvement in BCVA at the final follow-up. The corneal graft remained clear in nine eyes (40.9%) at a median duration of 3 years. The overall average survival period for all corneal grafts was 42.9 months. Conclusions The combination of sutured scleral-fixated intraocular lens implants and PKP is an effective intervention for preserving visual acuity in patients with complex cases. However, the risk of graft failure and then need for repeat transplantation should be taken into consideration.

Introduction: Complex corneal conditions present surgical challenges and necessitate innovation. Here, we present two cases where we performed intraocular lens trans-scleral fixation using the double-needle Yamane technique, followed by penetrating keratoplasty and vitrectomy using a temporary Landers wide-field keratoprosthesis. Case Presentation: Case 1 involved a 70-year-old man with an aphakic eye of bullous keratopathy and corneal opacity owing to multiple penetrating and endothelial keratoplasty, endophthalmitis, and herpetic keratitis. His visual acuity was counting fingers at 20 cm before surgery. Penetrating keratoplasty with vitrectomy and intraocular lens scleral fixation was performed using the double-needle Yamane technique, and 10 months postoperatively, his best-corrected visual acuity improved to 0.6, presenting a clear cornea. Case 2 involved a 62-year-old man who underwent penetrating keratoplasty twice for corneal perforation and therapeutic penetrating keratoplasty with vitrectomy for traumatic globe rupture, resulting in the loss of the intraocular lens. The patient exhibited graft failure, and his best-corrected visual acuity was 0.03. Utilizing a temporary Landers wide-field keratoprosthesis, we performed penetrating keratoplasty and intraocular lens trans-scleral fixation without complications. His final best-corrected visual acuity improved to 0.15 with a clear cornea. Conclusions: Trans-scleral fixation of intraocular lens with penetrating keratoplasty, using temporary Landers wide-field keratoprosthesis, yielded positive clinical outcomes without serious complications.

Purpose: to determine the concentration of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in the tear of patients with cornea melting and to assess whether these factors can be used as prognostically significant biomarkers of keratolysis. Material and methods. 20 patients who underwent urgent penetrating keratoplasty were tested for cornea perforation (melting) before and after the procedure. For control, 12 healthy adults (24 eyes) were tested. The tear fluid was collected before the surgery and on the 7th day after it with the help of filtering paper. MMP-9 and TIMP-1 concentrations were determined by ELISA. The course of the early postoperative period was assessed according to the area of keratotransplant epithelization on the 7th day after surgery. Results. MMP-9 and TIMP-1 concentrations in the tears of all patients before the surgery were significantly higher than the ones of healthy controls. The patients who were supposed to have re-keratoplasty had a significantly higher MMP-9 concentration than the ones who expected the first keratoplasty. An uncomplicated early postoperative period showed a statistically significant decrease of MMP-9 and TIMP-1 concentrations, whilst the complicated one demonstrated a significant increase of both markers. The highest increase of both markers was shown by the patients who underwent re-keratoplasty. Conclusion. MMP-9 concentration in the tears is a valid marker of the clinical course of the early post-keratoplasty period. To ensure a successful donor cornea engraftment, the levels of MMP-9 and TIMP-1 in the tear must be high enough before the surgery and the concentration of the ferment should decrease timely after its main functions have been completed. A 2-fold (or greater) decrease of MMP-9 concentration in the tear on the 7th day after keratoplasty can be considered a marker of the favorable prognosis for engraftment.

Abstract To evaluate the clinical implications of the different trypan blue dyeing techniques used during liquid bubble (LBT) and manual peel (MPT) DMEK lenticule preparation techniques. This study retrospectively compared the degree to which endothelial cells are preserved using selective Descemet Membrane (DM) staining (LBT) versus bath-staining (MPT) when performed by a single surgeon, sourced from a single eye bank. Endothelial cell density measured after the 3-month follow-up was 1805 and 1916 cells/mm2 respectively, differing significantly (p = 0.012). A double-scroll graft formation was found and maintained until implantation in 94% of preparations with bath staining and 50% of preparations using selective DM staining. Preoperative visual acuity was comparable between preparation techniques at 0.4 logMAR as well as postoperatively, at an average of 0.1 logMAR. Reducing chemical stress on the endothelium by avoiding any contact with trypan blue allows for a significantly higher degree of cell preservation. However, achieving the often-desired double-scroll graft formation was possible less frequently. It remains unclear which factors define the differences graft scrolling behavior observed between LBT and MPT.

Introduction: Corneal graft detachment is a major postoperative complication of Descemet’s stripping automated endothelial keratoplasty (DSAEK). When a corneal graft becomes detached, corneal endothelial function generally fails, and repeat corneal transplantation is required. Herein, we report a rare case in which a transparent cornea was maintained after the removal of a dislocated DSAEK graft. Case Presentation: A 79-year-old woman with a residual lens cortex who had undergone cataract surgery was referred to our hospital. The cortex was removed, and bullous keratopathy progressed. Six months after the initial surgery, DSAEK was performed under topical anesthesia without any complications. Although the corneal graft had attached fairly well, it detached from the host cornea 3 weeks later. Two months after DSAEK, an air tamponade was used to treat the anterior chamber with single interrupted suturing; however, the graft detached again, except for the suture site. Because the detached cornea became cloudy in the anterior chamber, it was surgically removed 8 months after DSAEK. Accordingly, the host cornea transparency improved to a best-corrected visual acuity of 0.8 with a rigid gas permeable lens and a central corneal thickness of 580 μm. The corneal endothelial cell density was 995 cells/mm2. Conclusion: Removal of the corneal graft from the dislocated cloudy graft improved the visual acuity of this patient after DSAEK. The condition of the cornea should be carefully monitored after corneal endothelial transplantation, even after the graft has been dislocated.

Background: The purpose of the study was to assess visual outcomes, complications, intraocular lens (IOL) stability, and corneal status after sutured scleral-fixated intraocular lens implantation combined with penetrating keratoplasty (PKP). Methods: This retrospective single-arm cohort study included patients who underwent PKP and sutured scleral-fixated intraocular lens implantation between 2013 and 2018 at the Dhahran Eye Specialty Hospital. The eyes were examined postoperatively at 1, 3, 6, 12, and 24 months. Corneal status, complications, and IOL status were also evaluated periodically, and the number of eyes with a BCVA of > 20/200 was recorded. Results: Twenty-two eyes from 22 patients were included. The median duration of follow-up was 3 (IQR 1.8; 4.4) years. Reasons for surgery were traumatic globe rupture (six eyes, 27.3%), bullous keratopathy (nine eyes, 40.1%), failed previous graft (five eyes, 22.7%), and corneal scarring (two eyes, 9.1%). Twelve (54.5%) eyes showed a BCVA of > 20/200 (non-blind) at 12 months after surgery and only five (22.7%) before surgery. Twelve months after surgery, 13 patients showed an improvement in BCVA in two lines (59.1%), seven remained the same (31.8%), and 2 deteriorated (9.1%). The indication for surgery (p = 0.2) and the stability of the sutured-scleral fixated IOL (p = 0.8) were not associated with an improvement in BCVA at the final follow-up. The corneal graft remained clear in nine eyes (40.9%) at a median duration of 3 years. The overall average survival period for all corneal grafts was 42.9 months. Conclusions: The combination of sutured scleral-fixated intraocular lens implants and PKP is an effective intervention for preserving visual acuity in patients with complex cases. However, the risk of graft failure and then need for repeat transplantation should be taken into consideration. [ABSTRACT FROM AUTHOR]

Investigate trends in keratoconus (KCN) treatment patterns and diagnosis age from 2015 to 2020 and evaluate sociodemographic associations with the treatment approach. Retrospective cohort study. Patients with a new KCN diagnosis from 2015 to 2020 were identified in the Academy IRIS® Registry (Intelligent Research in Sight). Associations between sociodemographic factors and treatment were evaluated using multivariable logistic regression. Outcomes included percentages and rates of each treatment (collagen crosslinking [CXL], keratoplasty, or no procedure) from 2015 to 2020, age at diagnosis during this period, and sociodemographic factors associated with treatment type. A total of 66 199 patients with a new diagnosis of KCN were identified. The percentage of patients undergoing CXL increased from 0.05% in 2015 to 29.5% in 2020 (P = 0.008). The average age (standard deviation) of KCN patients decreased from 44.1 (±16.9) years in 2015 to 39.2 (±16.9) years in 2020 (P < 0.001). In multivariable analyses comparing CXL versus no procedure and keratoplasty versus no procedure, patients undergoing CXL tended to be younger with the odds of having CXL decreasing with increasing age, for example, comparing CXL and no procedure patients, using ages 0–20 years as reference, the odds ratio (OR) (95% confidence interval [CI]) decreased from 0.62 (0.57–0.67; P < 0.0001) for patients aged 21–40 years to 0.03 (0.02–0.04; P < 0.0001) for patients aged > 60 years. Men were more likely than women to have CXL (OR, 1.31; 95% CI, 1.23–1.40; P < 0.0001) and keratoplasty (OR, 1.30; 95% CI, 1.19–1.42; P < 0.0001). Black patients were less likely than White patients to have CXL (OR, 0.70; 95% CI, 0.63–0.77; P < 0.0001) and more likely to have keratoplasty (OR, 2.24; 95% CI, 2.01–2.50; P < 0.0001). Likewise, Hispanic patients had higher odds of CXL (OR, 1.12; 95% CI, 1.00–1.24; P < 0.05) and keratoplasty (OR, 1.29; 95% CI, 1.12–1.50; P < 0.001) compared with non-Hispanic patients. Collagen crosslinking and keratoplasty also varied by region and insurance status. A significant increase in use of CXL was noted from 2015 to 2020. Sociodemographic differences in treatment among KCN patients may reflect differences in access, use, or care patterns, and future studies should aim to identify strategies to improve access for all patients. The author(s) have no proprietary or commercial interest in any materials discussed in this article. [ABSTRACT FROM AUTHOR]

To evaluate the clinical implications of the different trypan blue dyeing techniques used during liquid bubble (LBT) and manual peel (MPT) DMEK lenticule preparation techniques. This study retrospectively compared the degree to which endothelial cells are preserved using selective Descemet Membrane (DM) staining (LBT) versus bath-staining (MPT) when performed by a single surgeon, sourced from a single eye bank. Endothelial cell density measured after the 3-month follow-up was 1805 and 1916 cells/mm2 respectively, differing significantly (p = 0.012). A double-scroll graft formation was found and maintained until implantation in 94% of preparations with bath staining and 50% of preparations using selective DM staining. Preoperative visual acuity was comparable between preparation techniques at 0.4 logMAR as well as postoperatively, at an average of 0.1 logMAR. Reducing chemical stress on the endothelium by avoiding any contact with trypan blue allows for a significantly higher degree of cell preservation. However, achieving the often-desired double-scroll graft formation was possible less frequently. It remains unclear which factors define the differences graft scrolling behavior observed between LBT and MPT. [ABSTRACT FROM AUTHOR]

This review highlights the evolution in the scope of eye banking activities in India. The roles and responsibilities of the eye banks have expanded to match the requirements and necessities that arose because of advancements in keratoplasty techniques and the need for corneal surgeons. Adoption of different types of corneal preservation solutions and methods of donor cornea preservation was a consequence of the changing and unprecedented times. The growth of eye banking in India has been a commendable journey and has placed the country in an "almost sufficient" category in eye banking and corneal transplantation. There exists a potential to reach the status of cornea surplus country in the future. The rules and laws governing eye banking operations need dynamic amendments based on the trends in keratoplasty, surgical practice patterns, and status of self-sufficiency. Newer technological advances and quality measures must be adopted in donor cornea evaluation and tissue preparation. Research should be integrated as an important component of eye banking, especially in developing novel methods of donor preservation, and evaluating and validating the existing and changing practices of eye banking. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate ophthalmologists' interest and opinions regarding corneal transplantation and donation in Türkiye. Material and methods: An online questionnaire was prepared using Google Forms, and the electronic link to this questionnaire was sent via WhatsApp to ophthalmologists working in Türkiye. Eighteen open-ended/multiple-choice questions were asked about ophthalmologists' demographic information and their opinions regarding corneal transplantation and donation. The answers were analyzed by transferring the data to Excel. Results: A total of 195 ophthalmologists participated in the survey. While 68.6% of them stated that they wanted to donate their corneas, 21.1% stated that they were undecided, and 10.3% did not want to donate their corneas. While 93.8% of the participants agreed to have a cornea transplant in case of need, 5.7% of them stated that they were undecided, and 0.5% said that they would not accept a cornea transplant. The most frequent (90.5%) reason for being willing to donate one's cornea was to give hope to patients with low vision. The most frequent (46.2%) reason for not wanting to donate one's cornea was the unwillingness to have one's body/eye integrity impaired. The vast majority (80.8%) of the participants thought that there was not enough corneal donation in Türkiye and that this was mostly (85.9%) due to cultural and/or religious reasons. Conclusions: Even in a sample with a high level of education and the most knowledge about corneal transplantation, the willingness to donate corneas may remain below the expected rates. Therefore, it is necessary to alleviate unrealistic concerns and prejudices about corneal donation and transplantation. [ABSTRACT FROM AUTHOR]

Introduction: Corneal graft detachment is a major postoperative complication of Descemet’s stripping automated endothelial keratoplasty (DSAEK). When a corneal graft becomes detached, corneal endothelial function generally fails, and repeat corneal transplantation is required. Herein, we report a rare case in which a transparent cornea was maintained after the removal of a dislocated DSAEK graft. Case Presentation: A 79-year-old woman with a residual lens cortex who had undergone cataract surgery was referred to our hospital. The cortex was removed, and bullous keratopathy progressed. Six months after the initial surgery, DSAEK was performed under topical anesthesia without any complications. Although the corneal graft had attached fairly well, it detached from the host cornea 3 weeks later. Two months after DSAEK, an air tamponade was used to treat the anterior chamber with single interrupted suturing; however, the graft detached again, except for the suture site. Because the detached cornea became cloudy in the anterior chamber, it was surgically removed 8 months after DSAEK. Accordingly, the host cornea transparency improved to a best-corrected visual acuity of 0.8 with a rigid gas permeable lens and a central corneal thickness of 580 μm. The corneal endothelial cell density was 995 cells/mm2. Conclusion: Removal of the corneal graft from the dislocated cloudy graft improved the visual acuity of this patient after DSAEK. The condition of the cornea should be carefully monitored after corneal endothelial transplantation, even after the graft has been dislocated. [ABSTRACT FROM AUTHOR]

IntroductionDuring endothelial keratoplasty, anterior chamber gas is titrated to a desired fill, which is difficult to optimize by visualization alone. This study evaluates how an anterior chamber gas fill correlates with intraocular pressure (IOP) and iris-angle configuration as identified by optical coherence tomography (OCT).MethodsEleven cadaveric eyes were studied in three configurations: baseline, air-fill just spanning limbus-to-limbus (“full-fill”), and air-fill maximally filling the anterior chamber (“overfill”). At each configuration, IOP was measured by Tonopen and iris-angle was determined by analyzing OCT images.ResultsNo differences in IOP or irisangles were identified between baseline and full-fill configurations (p=0.113 and p=0.152, respectively). When compared to overfill configuration, differences in IOP and iris-angles were identified for baseline (p

Abstract Purpose To summarize the outcomes of corneal sight rehabilitating surgery in Stevens-Johnson syndrome (SJS). Methods This is a retrospective analysis of a consecutive case series. Twenty-four eyes of 18 SJS patients were included in this study. The ocular parameters, surgical procedures, postoperative complications, and additional treatments of the cases were reviewed. Results A total of 29 corneal sight rehabilitating surgeries, which consists of 9 keratoplasties, 8 Keratolimbal allograft (KLAL) and 12 combined surgeries (keratoplasty and KLAL simultaneously) were performed on the 24 eyes. All patients were treated with glucocorticoid eyedrops and tacrolimus eyedrops for anti-rejection treatment without combining systemic immunosuppression, except two patients who were prescribed prednisone tablets for the management of systemic conditions. The mean follow-up period was 50.6 ± 28.1 months. The optimal visual acuity (VA) (0.74 ± 0.60 logarithm of the minimum angle of resolution [logMAR]) and endpoint VA (1.06 ± 0.82 logMAR) were both significantly better than the preoperative VA (1.96 ± 0.43 logMAR) (95% CI, p = 0.000). 57.1% patients (8/14) were no longer in the low vision spectrum, and 88.9% patients (8/9) were no longer blind. The mean epithelialization time was 7.1 ± 7.6 weeks. The success rate was 86.7%. Additional treatments for improving epithelialization included administration of serum eyedrops (n = 10), contact lens (n = 15), amniotic membrane transplantation (n = 6), and tarsorrhaphy (n = 8). Complications included delayed epithelialization (n = 4, over 12 weeks), glaucoma (n = 11), and severe allograft opacity (n = 4). Only one graft rejection was observed. Conclusions Keratoplasty and KLAL can remarkably enhance VA and improve low vision or even eliminate blindness for ocular complications of SJS. The outcome of the surgeries was correlated with the preoperative ocular situation and choice of operative methods.

Abstract The purpose of this study is to evaluate loose suture-related inflammation and activation of conjunctiva-associated lymphoid tissue (CALT) in patients after keratoplasty. The patients who were treated with keratoplasty at the First Affiliated Hospital of Harbin Medical University between 2015 and 2022 were recruited into the study. We evaluated the time and location of loose suture development in patients after keratoplasty. In addition, in vivo confocal microscopy was used to evaluate the activation of CALT and the accumulation of inflammatory cells around loose sutures. Meso Scale Discovery assay detection kits were used to evaluate the inflammatory cytokines in the tears of patients before and after the loose suture was removed. In this study, we collected the information from 212 cases (212 eyes) who had PK (126 eyes) and DALK-treated (86 eyes) for corneal transplantation, including 124 males and 88 females, aged 14–84 years old. The average age was 50.65 ± 16.81 years old. Corneal sutures were more prone to loose at 3 months and 6 months after keratoplasty, and the frequent sites were at 5 and 6 o’clock. An increased number of inflammatory cells could be observed around the loose sutures than normal sutures (P

Abstract Background Familial calcific band-shaped keratopathy (BSK) is a very rare disease, with no underlying cause. There is no underlying disease in this form of the disease. This article introduces a family with seven children, three of whom were diagnosed with familial primary calcific BSK. One of them developed a systemic disease 38 years after ocular manifestation. Case presentation In this case report, three Iranian siblings from a family with familial calcific band-shaped keratopathy (BSK) are introduced. Systemic and ocular examinations performed on these patients indicated the occurrence of chronic kidney disease in the older child, a 41-year-old woman, 38 years after ocular manifestation. The examinations conducted on the other two siblings revealed no pathological findings. The 41-year-old sister and 37-year-old brother underwent unilateral deep anterior lamellar keratoplasty (DALK), while the 33-year-old sister underwent bilateral superficial keratectomy (SK). Conclusion Considering the late onset of systemic disease in one of the siblings diagnosed with familial calcific band-shaped keratopathy (BSK), it is crucial to emphasize the necessity of long-term follow-up for these patients and their families.

Corneal neovascularization can impair vision and result in a poor quality of life. The pathogenesis involves a complex interplay of angiogenic factors, notably vascular endothelial growth factor (VEGF). This review provides a comprehensive overview of potential therapies for corneal neovascularization, covering tissue inhibitors of metalloproteinases (TIMPs), transforming growth factor beta (TGF-β) inhibitors, interleukin-1L receptor antagonist (IL-1 Ra), nitric oxide synthase (NOS) isoforms, galectin-3 inhibitors, retinal pigment epithelium-derived factor (PEDF), platelet-derived growth factor (PDGF) receptor inhibitors, and surgical treatments. Conventional treatments include anti-VEGF therapy and laser interventions, while emerging therapies such as immunosuppressive drugs (cyclosporine and rapamycin) have been explored. Losartan and decorin are potential antifibrotic agents that mitigate TGF-β-induced fibrosis. Ocular nanosystems are innovative drug-delivery platforms that facilitate the targeted release of therapeutic agents. Gene therapies, such as small interfering RNA and antisense oligonucleotides, are promising approaches for selectively inhibiting angiogenesis-related gene expression. Aganirsen is efficacious in reducing the corneal neovascularization area without significant adverse effects. These multifaceted approaches underscore the corneal neovascularization management complexity and highlight ideas for enhancing therapeutic outcomes. Furthermore, the importance of combination therapies and the need for further research to develop specific inhibitors while considering their therapeutic efficacy and potential adverse effects are discussed. [ABSTRACT FROM AUTHOR]

Purpose: To summarize the outcomes of corneal sight rehabilitating surgery in Stevens-Johnson syndrome (SJS). Methods: This is a retrospective analysis of a consecutive case series. Twenty-four eyes of 18 SJS patients were included in this study. The ocular parameters, surgical procedures, postoperative complications, and additional treatments of the cases were reviewed. Results: A total of 29 corneal sight rehabilitating surgeries, which consists of 9 keratoplasties, 8 Keratolimbal allograft (KLAL) and 12 combined surgeries (keratoplasty and KLAL simultaneously) were performed on the 24 eyes. All patients were treated with glucocorticoid eyedrops and tacrolimus eyedrops for anti-rejection treatment without combining systemic immunosuppression, except two patients who were prescribed prednisone tablets for the management of systemic conditions. The mean follow-up period was 50.6 ± 28.1 months. The optimal visual acuity (VA) (0.74 ± 0.60 logarithm of the minimum angle of resolution [logMAR]) and endpoint VA (1.06 ± 0.82 logMAR) were both significantly better than the preoperative VA (1.96 ± 0.43 logMAR) (95% CI, p = 0.000). 57.1% patients (8/14) were no longer in the low vision spectrum, and 88.9% patients (8/9) were no longer blind. The mean epithelialization time was 7.1 ± 7.6 weeks. The success rate was 86.7%. Additional treatments for improving epithelialization included administration of serum eyedrops (n = 10), contact lens (n = 15), amniotic membrane transplantation (n = 6), and tarsorrhaphy (n = 8). Complications included delayed epithelialization (n = 4, over 12 weeks), glaucoma (n = 11), and severe allograft opacity (n = 4). Only one graft rejection was observed. Conclusions: Keratoplasty and KLAL can remarkably enhance VA and improve low vision or even eliminate blindness for ocular complications of SJS. The outcome of the surgeries was correlated with the preoperative ocular situation and choice of operative methods. [ABSTRACT FROM AUTHOR]

Background: To assess the long‐term incidence and risk factors for post‐keratoplasty infectious keratitis (IK), associated ocular pathogens, and antibiotic resistance profiles. Methods: Cohort study including 2553 consecutive penetrating, endothelial, and anterior lamellar keratoplasties performed between 1992 and 2020. Medical and microbiological records of patients clinically diagnosed with IK were retrospectively reviewed. Main outcome measures: cumulative incidence of IK, infectious agent species, and antibiotics resistance profiles. Results: The average follow‐up time after transplantation was 112 ± 96 months. Eighty‐nine IK episodes were recorded; microbiological tests were positive in 55/89 (62%). The cumulated incidence of postoperative IK was 5.50%/10.25% at 10/20 years. The occurrence of at least one episode of IK after transplantation was associated with lower graft survival in the long term (p < 0.0001). Rejection risk (adjusted Hazard Ratio, 2.29) and postoperative epithelial complications (HR, 3.44) were significantly and independently associated with a higher incidence of postoperative IK. Infectious agents included 41 bacteria, 10 HSV, 6 fungi, and 1 Acanthamoeba. The rate of antibiotic resistance was 0% for vancomycin, 13% for fluoroquinolones, 20% for rifamycin, 59% for aminoglycosides, and 73% for ticarcillin. In 41% of cases, patients were under prophylactic topical antibiotics before the infectious episode. Topical antibiotics were significantly associated with increased resistance to penicillin, carbapenems, and aminoglycosides. Conclusion: IK (mainly bacterial) is a frequent complication of corneal transplantation in the long term. Vancomycin and fluoroquinolones can be considered as first‐line treatments. Prolonged postoperative antibiotic preventive treatment is not advisable as it may increase antibiotic resistance. [ABSTRACT FROM AUTHOR]

Corneal stromal fibrosis is a common cause of visual impairment resulting from corneal injury, inflammation and surgery. Therefore, there is an unmet need for inhibiting corneal stromal fibrosis. However, bioavailability of topical eye drops is very low due to the tear and corneal barriers. In situ delivery offers a unique alternative to improve efficacy and minimize systemic toxicity. Herein, a drug delivery platform based on thermoresponsive injectable hydrogel/nano-micelles composite with in situ drug-controlled release and long-acting features is developed to prevent corneal scarring and reduce corneal stromal fibrosis in lamellar keratoplasty. The in-situ gelation hydrogels enabled direct delivery of celastrol to the corneal stroma. In vivo evaluation with a rabbit anterior lamellar keratoplasty model showed that hydrogel/micelles platform could effectively inhibit corneal stromal fibrosis. This strategy achieves controlled and prolonged release of celastrol in the corneal stroma of rabbit. Following a single corneal interlamellar injection, celastrol effectively alleviated fibrosis via mTORC1 signal promoting autophagy and inhibiting TGF-β1/Smad2/3 signaling pathway. Overall, this strategy demonstrates promise for the clinical application of celastrol in preventing corneal scarring and reducing corneal stromal fibrosis post-lamellar keratoplasty, highlighting the potential benefits of targeted drug delivery systems in ocular therapeutics. Thermoresponsive injectable and transparent hydrogel deliver drug locally to treat corneal scars and various eye diseases. [Display omitted] • An injectable thermoresponsive-hydrogel-based drug delivery platform was fabricated. • The in-situ gelation platform delivered celastrol directly to corneal stroma with controlled and prolonged release. • The platform hampered corneal scars in lamellar keratoplasty. • Celastrol alleviates fibrosis via promoting autophagy and inhibiting TGF-β1 pathway. [ABSTRACT FROM AUTHOR]

Purposes: This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy. Methods: In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates. Results: After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test). Conclusion: Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical outcomes, surgical indications, results of medical, surgical and micropulse transscleral cyclophotocoagulation (MP-TSCPC) treatment in patients with postkeratoplasty glaucoma Materials and Methods: Fifty-six eyes of 53 patients with glaucoma who had undergone keratoplasty were included in the study. Demographic and clinical characteristics, medical and surgical (either trabeculectomy or MP-TSCPC) treatment results were evaluated retrospectively. Results: The mean age of patients was 52.8 ± 19.1 years (9- 84). The most common indication for keratoplasty was bullous keratopathy in 15 eyes (26.8 %). The mean follow-up period was 29.3 ± 36.7 months. Glaucoma control was achieved by medical treatment in 46 (82.1%), MP-TSCPC in 5 (8.9%), trabeculectomy in 3(5.4%), and combined therapy in 2 (3.6%) of eyes. For MP-TSCPC cases the mean pre-treatment IOP was 28.5 mmHg and the mean post-treatment IOP was 14.6 mmHg. With % 40 reduction, the best results were taken in MP-TSCPC group. No patients had hipotony or graft failure. Conclusions: Glaucoma control can be achieved by medical, surgical and MP-TSCPC treatment in eyes with postkeratoplasty. MPTSCPC is a safe and effective IOP lowering method in these eyes. [ABSTRACT FROM AUTHOR]

The inner structures of the eye are protected by the cornea, which is a transparent membrane exposed to the external environment and subjected to the risk of lesions and diseases, sometimes resulting in impaired vision and blindness. Several eye pathologies can be treated with a keratoplasty, a surgical procedure aimed at replacing the cornea with tissues from human donors. Even though the success rate is high (up to 90% for the first graft in low-risk patients at 5-year follow-up), this approach is limited by the insufficient number of donors and several clinically relevant drawbacks. Alternatively, keratoprosthesis can be applied in an attempt to restore minimal functions of the cornea: For this reason, it is used only for high-risk patients. Recently, many biomaterials of both natural and synthetic origin have been developed as corneal substitutes to restore and replace diseased or injured corneas in low-risk patients. After illustrating the traditional clinical approaches, the present paper aims to review the most innovative solutions that have been recently proposed to regenerate the cornea, avoiding the use of donor tissues. Finally, innovative approaches to biological tissue 3D printing and xenotransplantation will be mentioned. [ABSTRACT FROM AUTHOR]

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Background: New developments in artificial intelligence, particularly with promising results in early detection and management of keratoconus, have favorably altered the natural history of the disease over the last few decades. Features of artificial intelligence in different machine such as anterior segment optical coherence tomography, and femtosecond laser technique have improved safety, precision, effectiveness, and predictability of treatment modalities of keratoconus (from contact lenses to keratoplasty techniques). These options ingrained in artificial intelligence are already underway and allow ophthalmologist to approach disease in the most non-invasive way. Objectives: This study comprehensively describes all of the treatment modalities of keratoconus considering machine learning strategies. Design: A multidimensional comprehensive systematic narrative review. Data sources and methods: A comprehensive search was done in the five main electronic databases (PubMed, Scopus, Web of Science, Embase, and Cochrane), without language and time or type of study restrictions. Afterward, eligible articles were selected by screening the titles and abstracts based on main mesh keywords. For potentially eligible articles, the full text was also reviewed. Results: Artificial intelligence demonstrates promise in keratoconus diagnosis and clinical management, spanning early detection (especially in subclinical cases), preoperative screening, postoperative ectasia prediction after keratorefractive surgery, and guiding surgical decisions. The majority of studies employed a solitary machine learning algorithm, whereas minor studies assessed multiple algorithms that evaluated the association of various keratoconus staging and management strategies. Last but not least, AI has proven effective in guiding the implantation of intracorneal ring segments in keratoconus corneas and predicting surgical outcomes. Conclusion: The efficient and widespread clinical translation of machine learning models in keratoconus management is a crucial goal of potential future approaches to better visual performance in keratoconus patients. Trial registration: The article has been registered through PROSPERO, an international database of prospectively registered systematic reviews, with the ID: CRD42022319338 Plain language summary: Keratoconus: from fundamentals to future Artificial intelligence has changed how we treat the eye disease keratoconus in recent years. This study examines the many keratoconus therapies available, including surgery and contact lens wear, and how artificial intelligence can improve the safety and accuracy of these procedures. We combed through numerous papers to locate this data. To achieve the best outcomes, several parameters and methods should be evaluated. According to the study, some elements from eye scans are more useful than others. The idea behind using artificial intelligence is to help patients see better and treat keratoconus more effectively. [ABSTRACT FROM AUTHOR]

Background: Familial calcific band-shaped keratopathy (BSK) is a very rare disease, with no underlying cause. There is no underlying disease in this form of the disease. This article introduces a family with seven children, three of whom were diagnosed with familial primary calcific BSK. One of them developed a systemic disease 38 years after ocular manifestation. Case presentation: In this case report, three Iranian siblings from a family with familial calcific band-shaped keratopathy (BSK) are introduced. Systemic and ocular examinations performed on these patients indicated the occurrence of chronic kidney disease in the older child, a 41-year-old woman, 38 years after ocular manifestation. The examinations conducted on the other two siblings revealed no pathological findings. The 41-year-old sister and 37-year-old brother underwent unilateral deep anterior lamellar keratoplasty (DALK), while the 33-year-old sister underwent bilateral superficial keratectomy (SK). Conclusion: Considering the late onset of systemic disease in one of the siblings diagnosed with familial calcific band-shaped keratopathy (BSK), it is crucial to emphasize the necessity of long-term follow-up for these patients and their families. [ABSTRACT FROM AUTHOR]

Purpose: To provide insights into morphologic and functional features of eyes with complicated Descemet's membrane detachment (DMD) and report clinical outcomes after surgical intervention. Methods: Retrospective study of 18 eyes with complicated DMD between 2010 and 2022. Complicated DMD was defined if any of the following criteria applied: prior penetrating keratoplasty (PKP), corneal thinning, total DMD or persistent DMD after Air/Gas-Descemetopexy. Causes, surgical management, and clinical outcomes were analyzed. Scheimpflug tomography, anterior segment optical coherence tomography (AS-OCT) and histologic examination were performed to characterize corneas with DMD. Results: Fourteen eyes with prior PKP developed spontaneous DMD after 24.2 ± 12.9 years (range = 18 months – 47 years, median = 25.7 years). Complicated DMD without prior PKP was associated in three eyes after cataract surgery and in one eye after infectious keratitis. In cases with previous PKP, AS-OCT demonstrated rupture of Descemet's membrane (DM) in five eyes and spontaneous reattachment was found in four eyes within 8 weeks of initial diagnosis, with no rupture of DM in any of the cases. There was no rupture of DM in corneas without previous PKP. After prior keratoplasty, definitive surgical treatment was repeat PKP in 13 eyes and Air/Gas-Descemetopexy in one eye. In corneas without prior keratoplasty, three eyes underwent PKP and one eye Air/Gas-Descemetopexy. Histological examination of two corneal explants revealed a severely thinned graft-host junction and a disrupted DM close to the graft-host junction. Visual acuity improved from 1.80 ± 0.58 logMAR to 0.75 ± 0.69 logMAR after prior PKP and from 1.45 ± 0.65 logMAR to 0.85 ± 1.13 logMAR without prior PKP. The postoperative course was uneventful in 16 of 18 eyes. Conclusion: PKP is an effective treatment option for complicated DMD, especially in ectatic corneas, whereas Air/Gas-Descemetopexy or Descemet Membrane Endothelial Keratoplasty do not address the primary issue of the curvature anomaly. [ABSTRACT FROM AUTHOR]

To compare prevalence of positive PCR tests for herpesviruses between patients with and without a history of clinical corneal endothelial allograft rejection (AGR). Retrospective cross‐sectional study with two‐group comparison. A total of 307 aqueous humor (AH) samples from 235 Patients and 244 eyes who underwent penetrating keratoplasty or Descemet membrane endothelial keratoplasty or had a diagnostic AH aspiration due to clinical AGR between 2019 and 2023 were tested for DNA of herpes simplex virus (HSV), varicella‐zoster virus (VZV), cytomegalovirus (CMV), and Epstein‐Barr virus (EBV). PCR test results were compared between the two groups (with/without AGR). Another sub‐analysis examined the results of patients without a history of herpetic keratitis. A total of 8% of eyes with clinical AGR (9/108) had a positive PCR result for one of the herpesviruses (HSV:3, CMV:3, EBV:2, VZV:1). All patients in the group without AGR had negative PCR results for all previous viruses (0/136). The difference was statistically significant (p < 0.001). The sub‐analysis of eyes without a history of herpetic keratitis also revealed significantly more positive herpes PCR results (7/87) in eyes with AGR than in eyes without AGR (0/42, p = 0.005). Clinical AGR after keratoplasty shows a significant correlation to viral replication. Herpetic infection and AGR could occur simultaneously and act synergistically. Timely differentiation between active herpetic infection and/or AGR is pivotal for proper treatment and graft preservation. [ABSTRACT FROM AUTHOR]

Corneal opacity is one of the leading causes of severe vision impairment. Corneal transplantation is the dominant therapy for irreversible corneal blindness. However, there is a worldwide shortage of donor grafts and consequently an urgent demand for alternatives. Three-dimensional (3D) bioprinting is an innovative additive manufacturing technology for high-resolution distribution of bioink to construct human tissues. The technology has shown great promise in the field of bone, cartilage and skin tissue construction. 3D bioprinting allows precise structural construction and functional cell printing, which makes it possible to print personalized full-thickness or lamellar corneal layers. Seed cells play an important role in producing corneal biological functions. And stem cells are potential seed cells for corneal tissue construction. In this review, the basic anatomy and physiology of the natural human cornea and the grafts for keratoplasties are introduced. Then, the applications of 3D bioprinting techniques and bioinks for corneal tissue construction and their interaction with seed cells are reviewed, and both the application and promising future of stem cells in corneal tissue engineering is discussed. Finally, the development trends requirements and challenges of using stem cells as seed cells in corneal graft construction are summarized, and future development directions are suggested.

Purpose: This report describes a case of Descemet membrane endothelial keratoplasty (DMEK) graft failure after non-clearing bullae over the area of the orientation mark on the graft. Methods: Case report. Results: The summary of the clinical presentation and workup is described, followed by a brief overview of the DMEK procedure and the gentian violet (GV) ink used to ensure the correct orientation of the DMEK graft. Conclusions: GV has a good safety profile; however, there are rare cases of adverse events. Therefore, alternative approaches should be explored, such as the use of intraoperative optical coherence tomography, reviewing a video recording of the insertion step, adjusting the insertion technique, or using asymmetrical trephine marking on graft edges.

Purpose: To determine the characteristics of an eye that developed acute hydrops while being treated for infectious keratitis. Observation: A 35-year-old man presented with pain and blurred vision in his left eye. He had undergone cataract surgery seven years earlier and was being treated for poorly controlled atopic dermatitis. The decimal best-corrected visual acuity (BCVA) of the left eye was 0.01. Slit-lamp microscopy showed conjunctival injection, corneal opacification, and a corneal ulcer. The patient was diagnosed with infectious keratitis and was treated with topical and systemic antibiotics. During the hospitalization, the patient was noted to rub his eyes frequently and vigorously. Five days after the first visit, the cornea protruded markedly, and the stroma surrounding the ulcerated area was edematous. These findings led to a diagnosis of acute hydrops.Penetrating keratoplasty was performed to prevent corneal perforation. Histopathological study of the excised cornea showed stromal edema, infiltration of leukocytes, and a tear in Descemet's membrane. Unfortunately, the patient developed endophthalmitis the day after the surgery. The anterior chamber was irrigated with antibiotics, and antibiotics were also injected into the vitreous. The endophthalmitis gradually subsided, and two years after the surgery, the patient's decimal BCVA had improved to 0.6. Conclusion and importance: Vigorous eye rubbing in cases of infectious keratitis can induce acute hydrops, and timely surgical intervention is recommended.

This review explores contemporary challenges in penetrating keratoplasty (PK), focusing on technical intricacies, technological advancements, and strategies for preventing graft rejection. A systematic literature search from January 2018 to July 2023 was conducted across PubMed, Cochrane, Web of Science, Scopus, and EMBASE. The inclusion criteria comprised studies on PK and its comparison with other corneal pathologies, with emphasis on keratoconus (KC). Two independent reviewers screened studies, extracting relevant data. The review covers PK evolution, highlighting infra-red femtosecond lasers' impact on graft shapes, minimizing astigmatism, and enhancing wound healing. Graft rejection, a primary complication, is examined, detailing risk factors and preventive measures. Preoperative considerations, diagnostic techniques for rejection, and PK in KC are discussed. Postoperative care's significance, including intraocular pressure monitoring and steroid administration, is emphasized. The paper concludes with a comprehensive approach to prevent graft rejection, involving topical and systemic medications. An outlook on evolving monoclonal antibody research is presented. As the field progresses, personalized approaches and ongoing therapeutic exploration are expected to refine strategies, enhancing PK outcomes.

Deep anterior lamellar keratoplasty (DALK) has emerged as a transformative approach in managing corneal pathologies, notably keratoconus (KC), providing a viable alternative to penetrating keratoplasty (PK). This systematic review explores the intricacies of DALK, comparing its preoperative, intraoperative, and postoperative considerations with PK. Extensive literature searches revealed a wealth of data regarding DALK's advantages and challenges, with an emphasis on graft survival, visual outcomes, and complications. In the preoperative phase, DALK showcases its versatility, catering to a wide spectrum of patients, including those with KC and ocular surface disorders. Intraoperatively, it offers innovative techniques to address emphysema, bubble formation, and Descemet's membrane perforation, all while maintaining a strong focus on patient-centered outcomes. Postoperatively, DALK's lower rejection rates and decreased complications underscore its potential superiority over PK, although unique challenges such as graft failure from nonimmunologic factors demand vigilant management. This comprehensive review not only serves as a valuable resource for ophthalmic surgeons but also sheds light on the evolving landscape of corneal transplantation, highlighting DALK's role as a transformative force in the field.

This paper illustrates the improvement of needle positioning precision within corneal tissue by an automated needle insertion system utilizing a vacuum applanation pad. The system is designed to streamline the needle insertion process for deep anterior lamellar keratoplasty (DALK), where precise positioning of the needle tip is essential for successful pneumatic dissection of the diseased corneal tissue. The vacuum applanation pad of the system can fixate and flatten the corneal tissue, resulting in a fixed uniform tissue region. By penetrating the needle into the fixture region, tissue deformation - which can negatively influence needle positioning accuracy - could be minimized. Furthermore, a needle selection process regarding the gauge and length was performed to determine the optimal needle parameter with minimal end tip deflection, and a Luer lock needle fixture was designed to provide roller support that can additionally suppress deflection. Two target needle depths (400 and $500~\mu \text{m}$ ) were set to evaluate the proposed system. Ten cadaveric porcine eyes were tested for each target depth and a total of 20 data points were acquired. As a result, the system could achieve a needle end tip depth of $373.9\pm 15.9~\mu \text{m}$ (Target: $400~\mu \text{m}$ ) and $441.3\pm 22.2~\mu \text{m}$ (Target: $500~\mu \text{m}$ ), showing an overall standard deviation of $21.1~\mu \text{m}$ from the target depth. Therefore, the proposed system could achieve precise positioning of the needle within the corneal tissue to the target depth without relying on feedback information, such as that provided by real-time optical coherence tomography.

The aim of this paper is to present the surgical technique of selective Bowman's layer transplantation as well as the results of the surgery in patients with trophic corneal ulcers. The methodology of the study included three eyes from three patients with neurotrophic corneal ulcers grafting with corneal Bowman's layer. Pre- and postoperative analyses of the anterior segment of the eye were based on optical coherence tomography and slit-lamp assessment. Postoperatively a gradual corneal stroma restoration and fast corneal epithelialization were noticed. Based on our observations, the stiff and firm structure of Bowman's layer is supposed to strengthen the corneal surface and maintain its shape. It acts also as an antipathogen and antitoxin corneal barrier. Application of this acellular corneal layer transplantation to cover trophic corneal ulcers is an interesting, modern and crucial method of neurotrophic keratitis treatment.

Purpose: to evaluate the effectiveness of silicon-dried cornea, previously subjected to corneal collagen UVA crosslinking, for urgent keratoplasty.Material and methods. 28 patients (16 males, 12 females), diagnosed with perforating corneal ulcer of various etiologies, underwent penetrating keratoplasty for eye-preserving purposes. 14 patients (the main group) underwent transplantation of a silicon-dried cornea, previously subjected to corneal collagen crosslinking according to the standard (Dresden) protocol while the remaining 14 patients (comparison group) underwent penetrating keratoplasty with not pre-treated silicon-dried cornea. In the postoperative period, we measured the time of primary complete epithelization of the graft and assessed the presence/absence of ulcers and erosions of the corneal graft 1, 3, 6 and 12 months after the discharge from the hospital. For this purpose, all patients underwent corneal biomicroscopy with corneal surface preliminary stained with a 1% sodium fluorescein solution.Results. Complete epithelization in both the main group and the comparison group was found to take place, on average, at the same time after surgery. However, over the entire observation period, the main group showed fewer relapses of ulcers and corneal graft erosions than the comparison group.Conclusion. The use of silicon-dried cornea, subjected to corneal collagen cross-linking, increases the effectiveness of perforated corneal ulcer treatment in emergency surgical care.

Despite tremendous developments in the field of laboratory testing in transplantation, the rules of eligibility for corneal transplantation still do not include typing of human leukocyte antigens (HLAs) in the donor and recipient or detection of donor-specific antibodies (DSAs) in the patient. The standard use of diagnostic algorithms is due to the cornea belonging to immunologically privileged tissues, which usually determines the success of transplantation of this tissue. A medical problem is posed by patients at high risk of transplant rejection, in whom the immune privilege of the eye is abolished and the risk of transplant failure increases. Critical to the success of transplantation in patients at high risk of corneal rejection may be the selection of an HLA-matched donor and recipient, and the detection of existing and/or de novo emerging DSAs in the patient. Incorporating the assessment of these parameters into routine diagnostics may contribute to establishing immune risk stratification for transplant rejection and effective personalized therapy for patients.

Corneal blindness is an important contributor to the burden of global blindness and has a greater prevalence in low-income countries of the developing world where resources and infrastructure are limited. The causes of corneal blindness too are different from high-income countries and include infectious keratitis, ocular trauma, and xerophthalmia. Persons with these indications tend to have unfavourable outcomes after corneal transplantation, limiting their chances of benefitting from this sight-saving procedure. However, most causes of corneal blindness in the developing world are preventable. This highlights the importance of understanding the unique challenges in these regions and the need for targeted interventions. This article discusses various prevention strategies, including primordial, primary, and secondary prevention, aimed at reducing the burden of corneal blindness in low-income countries. These include capacity building, training, and awareness campaigns to reduce the risk factors of ocular trauma, infectious keratitis, and to improve access to first aid. It is also important to promote safe eye practices and tackle nutritional deficiencies through public health interventions and policy changes. Providing the required training to general ophthalmologists in the management of basic corneal surgeries and diseases and enhancing the accessibility of eye care services in rural areas will ensure early treatment and prevent sequelae. Current treatment modalities belong to the tertiary level of prevention and are largely limited to corneal transplantation. In developing nations, there is a scarcity of donor corneal tissue necessitating an urgent expansion of eye banking services. Alternative approaches to corneal transplantation such as 3D printed corneas, cultured stem cells, and biomaterials should also be explored to meet this demand. Thus, there is a need for collaborative efforts between healthcare professionals, policymakers, and communities to implement effective prevention strategies and reduce the prevalence of corneal blindness in the developing world.