Surgery for glaucoma in modern corneal graft procedures

A systematic review and network meta-analysis of surgical interventions for glaucoma following penetrating keratoplasty

This study aims to compare the effectiveness and safety of surgical interventions for secondary glaucoma following penetrating keratoplasty (PKP) through a network meta-analysis. PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, Scopus, and Google Scholar databases were searched for articles published from inception to July 16, 2024. We included studies that compared the effects of trabeculectomy, glaucoma drainage devices (GDDs), or cyclophotocoagulation (CPC) on graft failure, intraocular pressure (IOP), or the number of glaucoma medications required for patients with post-PKP glaucoma. Based on data synthesized from 13 cohort studies, we observed that valved GDDs are not associated with a higher risk of graft failure (risk ratio [RR], 1.49; 95% confidence interval [CI], 0.89 to 2.48) compared with trabeculectomy with antifibrotic agents. Valved GDDs demonstrated greater benefits in achieving successful IOP control (RR, 1.33; 95% CI, 1.08 to 1.64), reducing IOP from baseline (mean difference [MD], - 3.08; 95% CI, - 5.36 to - 0.81), and reducing the number of glaucoma medication usage from baseline (MD, - 0.53; 95% CI, - 0.94 to - 0.12) compared with trabeculectomy with antifibrotic agents. In conclusion, valved GDDs may be the preferred surgical option for managing post-PKP glaucoma.

Efficacy and Safety of Ab-Interno Canaloplasty in Post-Keratoplasty Patients: 3-Year Results

Purpose

To evaluate the effectiveness and safety of ab-interno canaloplasty (ABiC) for managing intraocular pressure (IOP) in patients following keratoplasty over a three-year period.

Methods

This retrospective analysis focused on post-keratoplasty patients treated with ABiC with the iTrack microcatheter (Nova Eye Medical, Fremont, CA, USA) at a single institution. The study assessed the procedure's impact on IOP control, graft survival, and reliance on topical hypotensive medications, with additional observation for any postoperative complications. Surgical success criteria included the percentage of eyes with IOP ≤15 mmHg, IOP ≤18 mmHg, ≥20% IOP reduction, medication-free eyes, and eyes with concurrent IOP and medication reductions.

Results

ABiC was performed successfully in a cohort of 16 post-keratoplasty (7 penetrating keratoplasty and 9 endothelial keratoplasty (EK)) eyes. Preoperative mean IOP of 25.8±7.2 mmHg was significantly reduced to 13.4±2.9 mmHg (p<0.001) at 1 year postoperatively and maintained at 13.1±3.9 mmHg (p=0.009) at 3 years postoperatively. The mean number of glaucoma medications was 3.5±1.7 at baseline, 2.8±1.3 at 1 year (p=0.107), and 2.5±1.2 at 3 years postoperatively (p=0.088). Eight eyes (66.7%) maintained IOP ≤ 15 mmHg, and 10 eyes (83.3%) maintained ≥ 20% IOP reduction at 3 years. The mean IOP and medication reductions from baseline at 3 years were -49.2% and -28.6%, respectively. Graft clarity was preserved in all patients except for one case of late graft failure that necessitated a repeat EK procedure. Post-ABiC complications included transient hyphema in two patients, neither of which led to long-term adverse outcomes.

Conclusion

ABiC appears to be an effective and safe surgical intervention for sustained IOP reduction in post-keratoplasty patients. Graft survival trends are encouraging, and there was a low incidence of complications over a three-year follow-up period.

Phakic intraocular Lens implantation in keratoconus patients

BACKGROUND

Both the anterior chamber and posterior chamber phakic intraocular lenses (pIOLs) implantation are acceptable refractive surgical approaches in keratoconus patients with high anisometropia, contact lens intolerance, or who prefer spectacle and contact lens independent. They are beneficial for correcting anisometropia in stable keratoconus cases or following corneal procedures such as intrastromal corneal ring segments (ICRS), collagen cross-linking (CXL), and keratoplasty. They are suitable for eyes without advanced keratoconus with acceptable best-corrected distance visual acuity (BCDVA) or without highly irregular astigmatism, high comma, and higher-order aberrations (HOAs). Combined procedures for irregular astigmatism reduction and corneal regularization with either ICRS or topography/wavefront-guided transepithelial PRK (with or without CXL) can be associated in advance with pIOLs implantation to improve BCDVA in these cases.

AIM

To study and report the evidence regarding the safety and efficacy of pIOLs for KC patients' visual and refractive rehabilitation, we have analyzed the scientific evidence published within the last 10 years (from 2012 onwards).

RESULTS

No randomized controlled trials but only eleven retrospective case series and two prospective case series were identified. Satisfactory visual rehabilitation was achieved regarding uncorrected and corrected distance visual acuity (CDVA) and predictability of the refractive correction. Both types of pIOL (iris claw and posterior chamber pIOLs) offer very good results in terms of safety and efficacy with indexes close to or even exceeding 1.

CONCLUSION

pIOLs implantation is a valid refractive therapeutic approach for correcting stable keratoconus with moderate-to-high refractive errors, especially anisometropia associated with regular or mildly irregular astigmatism, and good CDVA.

A Descriptive Study of Corneal Graft Failure in Retransplant Patients

OBJECTIVE

To identify the main predictors for corneal graft failure in patients who underwent retransplantation.

METHOD

This is a cross-sectional research with a quantitative and analytical approach, conducted based on data from secondary sources of a Human Eye Tissue Bank (HETB) in Northeast Brazil. Data were collected from the medical charts of all patients transplanted between January 2010 and December 2014. Descriptive statistics were used for the univariate analysis by means of absolute and relative frequencies and means. For the inferential analysis, the chi-square (X²) and the Fisher's Exact tests were used.

RESULTS

A total of 241 records were reviewed, representing 258 keratoplasties, of which 27 (10.46%) were retransplantations due to corneal graft failure. Of the total, 55.56% of the individuals were female, with a mean age of 58.56 years, 55.56% of the population was brown, and the highest relative frequency of housing found was in the Central Mesoregion. Of the corneal graft failure cases, 88.89% were due to late failure, 30.77% of cases were classified as pseudophakic and 11.57% as aphakic. Through inferential analysis, a statistical association was obtained among the variable "corneal graft failure" and mesoregion of the state, presence of glaucoma, vascularization, and classification of the eye.

CONCLUSION

The prognosis of keratoplasty is of multifactorial nature. Factors such as mesoregion of the State (place of residence), glaucoma, corneal vascularization, and aphakic eyes represent predictors for graft failure in the analyzed sample.

Outcomes after reversed corneal graft rejection: a report from the European VISICORT project

OBJECTIVE

This study aims to describe the outcome of corneal grafts, both low risk and high risk, after successfully reversed immunological rejection.

METHODS

Datasets on reversed rejection episodes in penetrating and endothelial keratoplasties between 2014 and 2019 (n=876) were extracted from the Adverse Immune Signatures and their Prevention in Corneal Transplantation database, which contains the prospectively and consecutively collected corneal transplants from five European centres. Stratified by the preoperatively determined risk status for immunological rejection, the outcome parameters analysed included visual acuity, intraocular pressure, endothelial cell density and central corneal thickness before and after reversed rejection episodes.

RESULTS

Fourty-seven (52%) out of a total of 91 identified rejection episodes were successfully reversed and were available for analysis (23 penetrating and 24 endothelial keratoplasties). No statistically significant change was found for any of the parameters studied between the values before and the values 3 months after the rejection episode, irrespective of the preoperative risk status.

CONCLUSION

The outcome of corneal grafts that survive immunological rejection may be clinically indistinguishable from the state before immunological rejection, irrespective of graft type and risk status. These findings support clinicians by providing information on prognosis after reversed rejection episodes and by giving patients realistic expectations regarding the outcome.

Mechanism and treatment of secondary glaucoma after corneal transplantation: a review

Corneal transplantation is a common treatment for corneal diseases. Secondary glaucoma after corneal transplantation is the second leading cause of failure of keratoplasty. This article reviews the mechanism and treatment of secondary glaucoma after corneal transplantation.

Risk Factors for Corneal Endothelial Decompensation after Penetrating Keratoplasty: A Population-Based Cohort Study

(1) Background: Endothelial decompensation is a common complication after penetrating keratopathy (PK), while the risk factors for endothelial decompensation after PK have not been fully elucidated. Consequently, we aim to investigate the possible risk factors for endothelial decompensation after PK. (2) Methods: This retrospective study was conducted using the National Health Insurance Research Database (NHIRD) of Taiwan. The main outcome was the development of endothelial decompensation after PK surgery. The effects of potential risk factors were compared between the patients with endothelial decompensation and the patients without endothelial decompensation via Cox proportional hazard regression, which produced the adjusted hazard ratio (aHR) and a 95% confidence interval (CI). (3) Results: Overall, 54 patients developed endothelial decompensation after PK surgery, with a ratio of 16.12 percent. The pre-existing type 2 diabetes mellitus (T2DM) (aHR: 1.924, 95% CI: 1.257-2.533, p = 0.0095) and history of cataract surgery (aHR: 1.687, 95% CI: 1.328-2.440, p = 0.0026) were correlated with the development of endothelial decompensation. In the subgroup analysis, the correlation between a history of cataract surgery and post-PK endothelial decompensation was more prominent in patients older than 60 years compared to their younger counterparts (p = 0.0038). (4) Conclusions: Pre-existing T2DM and a history of cataract surgery are associated with a higher incidence of post-PK endothelial decompensation.

Penetrating keratoplasty in brittle Cornea syndrome: Case series and review of the literature

It concerns three siblings (two 28 year old twin boys and a 25 year old woman) who presented a previous history of rupture of eyeball in one eye and very poor vision in the other. At the first ophthalmoscopic and instrumental evaluation, three patients presented with bluish sclera and keratoglobus in the intact eye. A genetic analysis with whole exome sequencing was then performed on the three siblings, identifying a biallelic variant of the PRDM5 gene that led to the diagnosis of Brittle Cornea Syndrome (BCS), a rare autosomal recessive disorder characterized by corneal thinning and blue sclera. To preserve the only intact eye from possible breakage, the three siblings were trained in using protective measures (polycarbonate goggles etc.) to carry out close monitoring of symptoms and were asked to continue with follow-up visits for ocular and systemic diseases associated with BCS. Given the poor best corrected visual acuity achievable with glasses and contact lenses, penetrating keratoplasty was performed, achieving good visual acuity maintained in the 2-year follow-up in two of the three patients. Knowledge of this pathology and its clinical manifestations is essential for early diagnosis and correct management of this rare but very debilitating pathology. To our knowledge, this is the first case series of BCS reported in an Albanian population.

DALK combined intralamellar tectonic patch graft: an alternative approach to treat frank corneal perforation

BACKGROUND

Deep anterior lamellar keratoplasty (DALK) has gained popularity in cases of corneal thinning and leaking descemetocele. In this study, we introduced an intralamellar tectonic patch graft in addition to conventional DALK procedures to treat frank cornea perforation.

METHODS

This retrospective case series included 13 patients (13 eyes) with frank corneal perforations who underwent DALK combined with intralamellar tectonic patch graft between December 2015 and December 2021. In addition to the standard DALK procedure, the perforation site was repaired with an extra intralamellar tectonic patch graft. The collected data included patient demographics, aetiology, size and location of the corneal perforation, visual acuity, surgical details, and postoperative complications.

RESULTS

Seven patients underwent autologous intralamellar patch grafts, whereas six received allogeneic ones. Anatomical success was achieved in all patients. The mean postoperative follow-up was 33.31 ± 25.96 months (6-73 months). The postoperative visual acuity (0.90 ± 0.65 logMAR) was significantly improved (P = 0.003) compared to the preoperative score (1.74 ± 0.83 logMAR). Best corrected visual acuity (BCVA) improved in 12 eyes (92.3%). The mean endothelial cell density was 2028 ± 463 cells/mm2, 6-12 months postoperatively. There was no recurrence of perforation, and the anterior lamellar graft remained transparent in 12 patients (92.3%). Postoperative complications included epithelial defects (23.1%), ocular hypertension (15.4%), and cataract (7.7%).

CONCLUSIONS

DALK combined with intralamellar tectonic patch graft may serve as a secure and effective alternative in treating frank corneal perforation, with reduced complications compared to conventional penetrating keratoplasty.

Outcomes of Corneal Transplant in Childhood Glaucoma

PRCIS

Childhood glaucoma produces alterations in the postnatal development and function of various ocular structures, including the cornea. Childhood glaucoma patients present lower corneal transplant survival rates. Our series shows outcomes of corneal transplant in childhood glaucoma with survival rates of 29% at 2 years.

OBJECTIVE

To investigate the surgical outcome of different types of keratoplasty in eyes with childhood glaucoma.

PATIENTS AND METHODS

A retrospective review was made of the medical records from 17 eyes of 15 patients who were diagnosed with childhood glaucoma and received a corneal transplantation between January 2010 and July 2020. Patient demographics, intraocular pressure, previous ocular surgery, comorbidities, corneal transplant surgery, and follow-up outcome were collected. The primary efficacy endpoint was graft survival (in months) until failure, the latter being considered as irreversible loss of corneal transparency. Secondary efficacy points were the need for an increase in topical hypotensive therapy and the need for additional surgery.

RESULTS

Seventeen eyes of 15 patients were included, 11 eyes (10 patients) with primary congenital glaucoma and 6 with other types of childhood glaucoma. Corneal transplantation was performed at the mean age of 23.76 ± 14.86 years. At the time of the transplantation, the number of topical medications was 1.35 ± 1.27, intraocular pressure was 15.00 ± 8.34 mm Hg, and patients had received up to 7 glaucoma surgeries. Descemet stripping automated endothelial keratoplasty was performed in 13 eyes (76%) and penetrating keratoplasty in 4 (24%). After surgery, 7 (41%) eyes required increased topical treatment and 2 (12%) glaucoma surgery. Twelve eyes (71%) developed graft failure at 24 months, the mean time of survival being 13.88 ± 8.25 months.

CONCLUSIONS

Management of corneal decompensation in childhood glaucoma poses a challenge. In this series of childhood glaucoma with corneal transplantations, the survival rate was 29% at 24 months.

Risk factors for intraocular pressure elevation following Descemet membrane endothelial keratoplasty in Asian patients

PURPOSE

To investigate risk factors for increased intraocular pressure (IOP) after Descemet membrane endothelial keratoplasty (DMEK) in Asian patients.

METHODS

Data from January 2015 to February 2021 were obtained from our prospective database. IOP elevation after DMEK was defined as IOP ≥ 22 mmHg or an increase in IOP of ≥ 10 mmHg from baseline. In addition, we examined maximum IOP. Using iCare, we measured IOP 1, 2, 3, and 6 months after DMEK, and every 6 months thereafter. Logistic regression and linear regression were performed to find factors predictive of IOP elevation and maximum IOP, respectively, based on the results of univariate analysis.

RESULTS

We enrolled 90 eyes (mean patient age, 74.9 ± 7.5 years; mean follow-up duration, 25.6 ± 9.9 months) that underwent DMEK. IOP elevation was present in 19 eyes (21%). IOP increased from 12.6 ± 3.9 mmHg preoperatively to a postoperative maximum of 17.0 ± 5.5 mmHg up to 36 months after DMEK (p < 0.0001). In univariate logistic regression analysis for IOP elevation, only one variable, pseudoexfoliation syndrome (PEX) and preexisting glaucoma, was significant (p < 0.05). Preexisting glaucoma without PEX (OR, 19.33; 95% CI, 4.75-93.46), PEX without glaucoma (OR, 7.25; 95% CI, 1.20-41.63), and PEX glaucoma (OR, 58.00; 95% CI, 6.78-1298.29) were associated with higher risk of IOP elevation.

CONCLUSIONS

In this cohort, the eyes of patients with PEX and preexisting glaucoma were found to be prone to IOP elevation after DMEK.

Surgical Management of Intraocular Pressure With Ab Interno Canaloplasty in Postkeratoplasty Patients: 12-Month Results

PURPOSE

The purpose of this study was to report clinical outcomes of ab interno canaloplasty (ABiC) with the iTrack microcatheter (Nova Eye Medical, Fremont, CA) for surgical management of intraocular pressure (IOP) in postkeratoplasty patients.

METHODS

This study was a single-center retrospective case series of postkeratoplasty eyes undergoing ABiC. Efficacy was evaluated based on graft survivability and mean reduction in IOP at 12 months postoperatively. Secondary end points consisted of visual acuity outcomes, number of topical hypotensive medications, and rate of complications.

RESULTS

ABiC was successfully performed in 17 eyes after keratoplasty (8 penetrating keratoplasty, 6 DSAEK, 2 penetrating keratoplasty + DSAEK, and 1 DMEK) with elevated IOP refractory to topical hypotensive medications. The baseline mean IOP was 26.2 ± 8.4 mm Hg and reduced significantly to 15.0 ± 4.21 mm Hg at 6 months and 13.0 ± 2.99 mm Hg at 12 months ( P < 0.005). The best-corrected visual acuity improved from 0.61 ± 0.55 logMAR at baseline to 0.47 ± 0.59 and 0.49 ± 0.64 at 6 and 12 months, respectively, following ABiC (not statistically significant: P = 0.6769). The baseline mean number of topical hypotensive medications was 3.7 ± 1.8 and reduced to 2.7 ± 1.4 and 2.9 ± 1.3 at 6 and 12 months, respectively ( P = 0.096). One patient developed a hyphema which required anterior chamber washout. One patient required additional glaucoma surgery 19 months after ABiC. No patients experienced graft failure.

CONCLUSIONS

ABiC is a clinically safe and effective treatment that can be performed in postkeratoplasty patients to reduce IOP for at least 1 year without any significant complications.

Incidence of Complications Related to Corneal Graft in a Group of 758 Patients

Purpose: this study aimed to assess the frequency of complications related to corneal grafts, including epithelialization disorders, wound dehiscence, infectious keratitis, recurrence of herpetic keratitis, graft rejection, late graft failure, and infectious and noninfectious corneal melting, while also considering risk factors, particularly indications. Methods: this retrospective analysis of corneal graft failure included a chart review of the hospital records of patients who underwent penetrating keratoplasty (PK) between January 2016 and December 2020 at the Department of Ophthalmology of the District Railway Hospital, Katowice, Poland. Results: Between 2016 and 2020, a total of 758 PK procedures were carried out at the ophthalmology department. Bullous keratopathy (20.58%), keratoconus (18.07%), and corneal perforation (13.32%) were the primary indications for keratoplasty. Secondary glaucoma was diagnosed in 99 patients (13.06%). The success rate of PK was 72.43% (494). The most frequent treatment complication was secondary glaucoma (13.06%), followed by late endothelial failure, perforation (4.1%), and bacterial keratitis (3.23%). Patients in the high-risk group were 4.65 times more likely to develop complications than those in the low-risk group. Multivariate regression analysis showed that concomitant ophthalmic diseases (odds ratio (OR): 3.12, confidence interval (CI): 1.60−6.08, p = 0.00) and connective tissue diseases (OR: 7.76, CI: 2.40−25.05, p = 0.00) were significant factors associated with the occurrence of complications. Diabetes, dermatological diseases, primary glaucoma, and sex were not associated with corneal graft failure (p > 0.05). Conclusion: Chronic loss of the endothelium was the primary cause of graft failure in individuals who underwent PK. The high-risk transplant has up to 4.65 times higher risk of complications compared to the indications with a good prognosis.

Assessing Corneal Endothelial Damage Using Terahertz Time-Domain Spectroscopy and Support Vector Machines

The endothelial layer of the cornea plays a critical role in regulating its hydration by actively controlling fluid intake in the tissue via transporting the excess fluid out to the aqueous humor. A damaged corneal endothelial layer leads to perturbations in tissue hydration and edema, which can impact corneal transparency and visual acuity. We utilized a non-contact terahertz (THz) scanner designed for imaging spherical targets to discriminate between ex vivo corneal samples with intact and damaged endothelial layers. To create varying grades of corneal edema, the intraocular pressures of the whole porcine eye globe samples (n = 19) were increased to either 25, 35 or 45 mmHg for 4 h before returning to normal pressure levels at 15 mmHg for the remaining 4 h. Changes in tissue hydration were assessed by differences in spectral slopes between 0.4 and 0.8 THz. Our results indicate that the THz response of the corneal samples can vary according to the differences in the endothelial cell density, as determined by SEM imaging. We show that this spectroscopic difference is statistically significant and can be used to assess the intactness of the endothelial layer. These results demonstrate that THz can noninvasively assess the corneal endothelium and provide valuable complimentary information for the study and diagnosis of corneal diseases that perturb the tissue hydration.

Clinical outcomes of slow-coagulation continuous-wave transscleral cyclophotocoagulation laser for treatment of glaucoma

PURPOSE OF REVIEW

The complications and inadequate efficacy of prior cyclodestructive procedures limited their role in glaucoma management. Recent advances in treatment techniques and parameters for laser cyclophotocoagulation has expanded its role in today's glaucoma practice. In this review, we discuss the treatment outcomes of slow-coagulation continuous-wave transscleral cyclophotocoagulation (CW-TSCPC) as a glaucoma surgical procedure for multiple types of glaucoma in lowering intraocular pressure (IOP).

RECENT FINDINGS

Slow-coagulation TSCPC is a relatively new technique for CW-TSCPC that, unlike the 'pop' power titration technique of laser energy delivery, aims to avoid the production of the 'pop' sound that signals explosive inflammatory energy delivery to the ciliary body and nearby tissue. In slow-coagulation TSCPC, laser energy is applied in a fixed and lower amount over a longer duration, compared with the conventional pop technique. This laser energy approach leads to more stable, reliable, titratable, and selective ciliary body ablation for control of IOP, especially relative to the controversial current use of micropulse TSCPC.

SUMMARY

Slow-coagulation CW-TSCPC can be used safely, efficiently, reproducibly, and efficaciously in wide range of glaucoma types including those with no history of incisional surgeries, good visual acuity, and medically refractory glaucomas.

Clinical Outcomes in Maximum Tolerated Medical Therapy in Penetrating Keratoplasty for Bullous Keratopathy

Purpose

To compare the clinical outcomes of maximum tolerated medical therapy (MTMT) in patients with penetrating keratoplasty (PKP) with those of Ahmed glaucoma valve (AGV) implantation.

Methods

The medical records were retrospectively reviewed in patients who had undergone PKP for bullous keratopathy and were treated with MTMT or AGV implantation for the management of glaucoma. A total of 18 bullous keratopathic patients were investigated between January 2010 and February 2017: 9 patients treated with MTMT and 9 patients treated with AGV implantation. Non-corrected visual acuity (NCVA), intraocular pressure (IOP), endothelial cell density (ECD), hexagonality, coefficient of variation (CV), central corneal thickness (CCT), median survival time of the graft, and the presence of epithelial keratopathy were compared between the groups at each time point or between baseline and after treatment of glaucoma in each group.

Results

There were no significant differences in the visual acuity and corneal thickness between the two groups or within each group over time. Both groups showed a significant reduction in IOP compared with the baseline IOP, and IOP reductions were greater in the AGV group than in the MTMT group (p = 0.040). Significant ECD reductions were found in each group between the baseline and 6 months (p = 0.008 in the MTMT group, p = 0.015 in the AGV group); however, no differences were found between the two groups until 12 months. The significant hexagonality reduction was found in the AGV group between the baseline and 12 months (p = 0.018). The median survival time showed no significant difference in the survival analysis.

Conclusions

Maximum tolerated medical therapy in penetrating keratoplasty for bullous keratopathy seems to similarly affect the endothelial cell density or graft survival when compared with at least 12 month-followed Ahmed glaucoma valve implantation.

Cosmetic Change of the Apparent Color of the Eye: A Review on Surgical Alternatives, Outcomes and Complications

An increasing number of people are seeking elective cosmetic change of eye color. We review the surgical techniques, outcomes and complications arising from the various existing surgical alternatives, including cosmetic iris implants—which based on the available evidence should be considered malpractice—as well as laser iris depigmentation and cosmetic keratopigmentation. Laser iris depigmentation has been used clinically for aesthetic purposes without receiving official approval or licensing. The technique can be performed in an outpatient clinic thanks to the use of neodymium: yttrium–aluminum–garnet (Nd:YAG) lasers, but scientific literature data about this treatment is very limited. Cosmetic iris implants are neither CE-marked nor Food and Drug Administration (FDA)-approved, and lead to severe complications arising from their placement including uveitis, hyphema, glaucoma, cataract, corneal endothelial damage and severe vision loss. Management of complications resulting from iris implants might require several surgical procedures, and the follow-up is difficult among these poorly informed patients. Keratopigmentation is the most extensively studied technique and had long been investigated before being introduced into clinical practice: already introduced centuries ago, it was recently developed, reporting adequate levels of safety and efficacy. The medium- and long-term cosmetic outcomes of keratopigmentation and patient satisfaction have been the subject of recent reports. The available level of evidence suggests that cosmetic keratopigmentation is the best evidence-supported surgical choice for patients seeking a permanent cosmetic eye color change. Still, additional investigation is needed to optimize the outcomes, minimize postoperative complications and further develop this and other new surgical alternatives such as laser procedures.

Evaluation of Demarcation Line after Epithelium-Off Iontophoresis Corneal Collagen Cross-Linking for Progressive Keratoconus

The aim of the study was to visualize and evaluate the characteristics and depth of the demarcation line with anterior segment optical coherence tomography (AS-OCT) after epithelium-off iontophoresis corneal collagen cross-linking (epi-off I-CXL). In this prospective, consecutive, single center study 18 eyes of 18 patients with keratoconus were involved. One month after epi-off I-CXL, all the patients underwent an AS-OCT scan to search for a demarcation line and its characteristics. The corneal stromal demarcation line was identified in all the eyes. Mean depth of the corneal stromal demarcation line was 261.8 ± 46.7 μm (range: 184 to 362 μm), at 56.7 ± 12% corneal depth. In conclusion, epi-off I-CXL determines a demarcation line that can be visualized with AS-OCT, which seems clearly distinguishable and similar to that created in standard CXL.

Refractive outcome and tomographic changes after Descemet membrane endothelial keratoplasty in pseudophakic eyes with Fuchs' endothelial dystrophy

Purpose

To analyze refractive and topographic changes secondary to Descemet membrane endothelial keratoplasty (DMEK) in pseudophakic eyes with Fuchs’ endothelial dystrophy (FED).

Methods

Eighty-seven pseudophakic eyes of 74 patients who underwent subsequent DMEK surgery for corneal endothelial decompensation and associated visual impairment were included. Median post-operative follow-up time was 12 months (range: 3–26 months). Main outcome measures were pre- and post-operative manifest refraction, anterior and posterior corneal astigmatism, simulated keratometry (CA_SimK) and Q value obtained by Scheimpflug imaging. Secondary outcome measures included corrected distance visual acuity (CDVA), central corneal densitometry, central corneal thickness, corneal volume (CV), anterior chamber volume (ACV) and anterior chamber depth (ACD).

Results

After DMEK surgery, mean pre-operative spherical equivalent (± SD) changed from + 0.04 ± 1.73 D to + 0.37 ± 1.30 D post-operatively (p = 0.06). CDVA, proportion of emmetropic eyes, ACV and ACD increased significantly during follow-up. There was also a significant decrease in posterior corneal astigmatism, central corneal densitometry, central corneal thickness and corneal volume over time (p = 0.001). Only anterior corneal astigmatism and simulated keratometry (CA_SimK) remained fairly stable after DMEK.

Conclusion

Despite tendencies toward a hyperopic shift, changes in SE were not significant and refraction remained overall stable in pseudophakic patients undergoing DMEK for FED. Analysis of corneal parameters by Scheimpflug imaging mainly revealed changes in posterior corneal astigmatism pointing out the relevance of posterior corneal profile changes during edema resolution after DMEK.

The Value of Anterior Segment Optical Coherence Tomography in Different Types of Corneal Infections: An Update

Anterior segment optical coherence tomography (AS-OCT) is a modality that uses low-coherence interferometry to visualize and assess anterior segment ocular features, offering several advantages of being a sterile and noncontact modality that generates high-resolution cross-sectional images of the tissues. The qualitative and quantitative information provided by AS-OCT may be extremely useful for the clinician in the assessment of a wide spectrum of corneal infections, guiding in the management and follow-up of these patients. In clinical practice, infections are routinely evaluated with slit-lamp biomicroscopy, an examination and imaging modality that is limited by the physical characteristics of light. As a consequence, the depth of pathology and the eventually associated corneal edema cannot be accurately measured with the slit-lamp. Therefore, it represents a limit for the clinician, as in vivo information about corneal diseases and the response to treatment is limited. Resolution of corneal infection is characterized by an early reduction in corneal edema, followed by a later reduction in infiltration: both parameters can be routinely measured with standardized serial images by AS-OCT.

Corneal transplant survival rate in glaucoma patients with multiple previous antiglaucoma surgeries

BACKGROUND

Glaucoma can cause corneal decompensation and accelerate the failure of the graft. Previous antiglaucoma operations are one of the most important risk factors for endothelial failure.

METHODS

In this retrospective study, 40 eyes of 40 glaucoma patients with advanced corneal decompensation after glaucoma surgery were treated with keratoplasty and outcomes were assessed for 24 months.

RESULTS

16, 9 and 15 eyes underwent Descemet Membrane Endothelial Keratoplasty (DMEK), Descemet's Stripping Automated Endothelial Keratoplasty (DSAEK) and penetrating keratoplasty (pKPL), respectively. Visual acuity improved at least 2 lines in 24 of 40 eyes after the three types of keratoplasty. All 40 eyes remained pain free for the follow-up period. The mean intraocular pressure (IOP) difference was not significantly different (p > 0.05) from the preoperative values 12 and 24 months after keratoplasty. The endothelial cell density of the donor cornea decreased from 2485.6 ± 165.18 to 1291.4 ± 467.1 and 1180.4 ± 397.2/mm² (p < 0.001) after 12 and 24 months, respectively. Nine eyes (22.5%) had therapy-resistant corneal decompensation in the context of a transplant failure and were treated with a re-keratoplasty (2 re-pKPLs, 3 re-DSAEKs and 3 re-DMEKs).

CONCLUSIONS

Eyes with previous glaucoma surgery show satisfying results after keratoplasty, mainly DMEK and pKPL.

Crystalline lens alterations in congenital aniridia

Congenital aniridia is a rare genetic disease associated with mutations in the PAX6 gene. Changes in the lens in aniridia can be alterations of size and shape, of position - which generally reveal zonular weakness and determines subluxation of the lens - and mainly changes in transparency, cataracts, with variable morphology of polar, cortical, subcapsular, lamellar, and more rarely, nuclear cataract. Visual acuity and quality of vision in patients with congenital aniridia complicated by cataracts can be improved by carefully planned surgery, when lack of media transparency justifies surgical indication. Most patients have some improvement in visual acuity and quality of retinal image. Cataract surgery with aniridia is complicated by pathological changes due to the underlying cause of the aniridia. Challenges include corneal opacification, friable capsule and, above all, iris and pupil reconstruction. It can also determine late complications, such as secondary glaucoma or deterioration of pre-existent glaucoma, and corneal endothelial decompensation. After crystalline lens surgery in these patients, either by cataract or dislocation, for visual rehabilitation there are various techniques such as keratopigmentation, prosthetic iris devices or Morcher intraocular lenses with a black diaphragm. An appropriate individualised surgical plan should be selected depending on patient and surgical experience, in order to minimise complications and give the best chance of postoperative success.