Boris Knyazer

Background: Contact lens-assisted corneal cross-linking can be used to treat keratoconus in patients with thin corneas under measuring less than 400 µm. This study compares the long-term clinical and tomographic outcomes between accelerated corneal cross-linking (A-CXL) and accelerated contact lens-assisted corneal cross-linking (A-CACXL). Methods: Patients who underwent either A-CXL or A-CACXL protocol due to progressive keratoconus were enrolled in this retrospective cohort study conducted between January 2015 and December 2018. The control group (patients with minimum corneal thickness of at least 400 µm, comprising 32 eyes of from 32 patients) was treated with A-CXL, whereas the treatment group (patients that had minimum corneal thickness after epithelial removal below 400 µm; 30 eyes of from 30 patients) underwent the A-CACXL protocol. Clinical and tomographic data were obtained from a 3-year follow-up period. Results: At 3 years, both groups represented a significant gain in best-corrected visual acuity (from 0.32 to 0.18 LogMAR units for A-CXL, p = 0.001; from 0.51 to 0.33 LogMAR units for A-CACXL, p = 0.037). Furthermore, postoperative tomographic parameters (Kmax, Kmean, or corneal astigmatism) were comparable between the two protocols. Progression of keratoconus was halted among 87% of eyes in the A-CXL group and among 73% of eyes in the A-CACXL group (p = 0.2). Conclusions: A-CACXL treatment is an effective and safe option for patients with keratoconus and thin corneas, yielding long term outcomes comparable to those of A-CXL treatment for patients with a minimum corneal thickness of 400 µm following a 3-year follow-up.

Background/Objectives: As one of the most efficacious glaucoma surgical techniques, trabeculectomy is considered by many surgeons to be the “gold standard” intra-ocular pressure (IOP)-reducing intervention. The purpose of this study is to present our intra-operative flow-adjusted surgical method, which aims to provide safety and efficacy more simply than previous methods. Methods: Retrospectively, we evaluated outcomes for trabeculectomy or phacotrabeculectomy in surgery-naïve eyes over three years for patients with glaucoma not associated with other ocular co-morbidities. We defined complete success as an IOP between 5 and 18 mmHg plus at least a 20% reduction from baseline, without concomitant medications. Relative success was the same result, with glaucoma medication(s). Failure was regarded as an IOP less than 5 or higher than 18 mmHg, or by the need for a subsequent glaucoma operation. Results: We assessed the results from 186 eyes of 186 patients. After exclusion, a group of 45 trabeculectomies and 35 phacotrabeculectomies were analyzed. In eyes undergoing a trabeculectomy, over a mean follow-up of 16.0 months, IOP fell from 28.1 ± 8.0 mmHg with 3.6 ± 1.1 medications to 9.7 ± 3.6 mmHg (66% reduction) with 0.4 ± 1.0 medications (each p < 0.00001). The success rate was 88.9% (75.6% complete success). In eyes undergoing a phacotrabeculectomy, over a mean of 19.1 months, IOP fell from 26.1 ± 10.2 mmHg with 3.5 ± 1.3 medications to 10.0 ± 3.6 mmHg (62% reduction) on 0.9 ± 1.4 medications (each p < 0.00001). The success rate was 91.4% (57.1% complete success). Complication rates were low, with no major complications in either group. Conclusion: To lower IOP, our intra-operative flow-adjusted trabeculectomy and phacotrabeculectomy techniques appear to be safe and effective.

Purpose: To assess clinical outcomes of corneal cross-linking (CXL) intervention in a population diagnosed with progressive keratoconus. Methods: This single-center retrospective cohort study included consecutive patients who underwent standard CXL or accelerated CXL for progressive keratoconus at a major teaching hospital in southern Israel between January 2015 and December 2019. Patients’ medical files were reviewed, and pre-operative and post-operative data regarding demographics and clinical and tomographic characteristics were extracted and analyzed. Results: This study included 166 patients (representing 198 eyes), out of which 98 patients (123 eyes) were ethnically Bedouin, and 68 patients (75 eyes) were ethnically Jewish. Overall, 126 patients (144 eyes) had a follow-up of at least 12 months (16.84 ± 5.76). The mean patient age was 20.62 ± 7.1 years old. There were significant baseline differences between the two ethnic groups in best-corrected visual acuity (BCVA; p < 0.001), uncorrected visual acuity (UCVA; p < 0.001), mean keratometry (p = 0.028), and corneal thickness (p < 0.001). Significant changes in BCVA, UCVA, and pachymetry parameters within each group were found after 12 months. Negative binomial regression analysis showed a maximal keratometry below 55D (RR = 1.247, p < 0.001), and a standard CXL procedure (RR = 1.147, p = 0.041) are significantly related to the stability of KC after 12 months. However, the effect size of the origin of patients is negligible (RR = 1.047, p = 0.47). Conclusions: In this study, the Bedouin population suffered from more progressive keratoconus when compared to the Jewish population. CXL was significantly effective in improving BCVA and UCVA in both groups after 12 months of follow-up. The effect size of the origin of patients on the stability of KC was found to be negligible.

Introduction: Photoactivated Chromophore for Infectious Keratitis-Corneal Cross-Linking (PACK-CXL) has garnered substantial interest among researchers and ophthalmologists due to its high promise as a potential treatment for infectious keratitis. The aim of this study is to evaluate the efficacy and safety of high fluence PACK-CXL, using 10.0 J/cm² (30 mW/cm², 5 min, and 33 s) at the slit lamp.Methods: This prospective interventional, nonrandomized cohort study included 20 eyes of 20 patients with bacterial, fungal, or mixed origin keratitis who underwent high fluence PACK-CXL treatment as an adjunct therapy to conventional antimicrobial therapy per American Academy of Ophthalmology treatment guidelines. The re-epithelization time was recorded, and corneal endothelial cell density was counted before and after treatment.Results: The average re-epithelization time was 8.2 ± 2.8 days (range 3–14 days). After PACK-CXL treatment, eight patients (40%) were directly discharged, while the remained patients stayed in the hospital for an average of 5.6 ± 3.5 days. No eyes required keratoplasty. Endothelial cell density counts before and after the PACK-CXL procedure were 2,562.1 ± 397.3, and 2,564.8 ± 404.5 cells/mm², respectively (p = 0.96).Conclusion: although it was not a randomized control trial, we conclude that high fluence PACK-CXL as an adjuvant therapy is safe with no complications observed, and efficient as time to re-epithelization was less than 14 days for all patients and no patients underwent tectonic keratoplasties. Further research is needed to compare it to the current standard of care.

Purpose: To assess clinical outcomes of corneal cross-linking (CXL) intervention in a population diagnosed with progressive keratoconus. Methods: This single-center retrospective cohort study included consecutive patients who underwent standard CXL or accelerated CXL for progressive keratoconus at a major teaching hospital in south Israel between January 2015 and December 2019. Patient medical files were reviewed to extract demographic, clinical, and tomographic data from outpatient clinic reports before treatment and one year post-operatively. Results: This study included 166 patients (representing 198 eyes), out of which 98 patients (123 eyes) were ethnically Bedouin, and 68 patients (75 eyes) were ethnically Jewish. Overall, 126 patients (144 eyes) had a follow-up of at least 12 months (16.84±5.76). The mean patient age was 20.62 ± 7.1 years old. There were significant baseline differences between the two ethnical groups in best-corrected visual acuity (BCVA; p < 0.001), uncorrected visual acuity (UCVA; p < 0.001), mean keratometry (p = 0.028), and corneal thickness (p < 0.001). Significant changes in BCVA, UCVA, and pachymetry parameters within each group were found after 12 months. Negative binomial regression analysis showed a maximal keratometry below 55D (RR=1.247, p < 0.001) and a standard CXL procedure (RR=1.147, p = 0.041) are significantly related to the stability of KC after 12 months. However, the effect size of the origin of patients is negligible (RR=1.047, p = 0.47). Conclusions: In this study, the Bedouin population suffered from more progressive keratoconus when compared to the Jewish population. CXL was significantly effective in improving BCVA and UCVA in both groups after 12 months of follow-up.

A healthy blood–brain barrier (BBB) shields the brain from high concentrations of blood glutamate, which can cause neurotoxicity and neurodegeneration. It is believed that traumatic brain injury (TBI) causes long-term BBB disruption, subsequently increasing brain glutamate in the blood, in addition to increased glutamate resulting from the neuronal injury. Here, we investigate the relationship between blood and brain glutamate levels in the context of BBB permeability. Rats exposed to BBB disruption through an osmotic model or TBI and treated with intravenous glutamate or saline were compared to control rats with an intact BBB treated with intravenous glutamate or saline. After BBB disruption and glutamate administration, the concentrations of glutamate in the cerebrospinal fluid and blood and brain tissue were analyzed. The results showed a strong correlation between the brain and blood glutamate concentrations in the groups with BBB disruption. We conclude that a healthy BBB protects the brain from high levels of blood glutamate, and the permeability of the BBB is a vital component in regulating levels of glutamate in the brain. These findings bring a new approach to treating the consequences of TBI and other diseases where long-term disruption of the BBB is the central mechanism of their development.

Background: Limbal stem cell deficiency (LCSD) presents several challenges. Currently, there is no clearly defined systematic approach to LSCD diagnosis that may guide surgical tactics. Methods: The medical records of 34 patients with LSCD were analyzed. Diagnostic modalities included standard (visometry, tonometry, visual field testing, slit-lamp biomicroscopy with corneal fluorescein staining, Schirmer test 1, ultrasonography) and advanced ophthalmic examination methods such as anterior segment optical coherence tomography, in vivo confocal microscopy, impression cytology, and enzyme-linked immunoassay. Results: Standard ophthalmological examination was sufficient to establish the diagnosis of LSCD in 20 (58.8%) cases, whereas advanced evaluation was needed in 14 (41.2%) cases. Depending on the results, patients with unilateral LSCD were scheduled to undergo glueless simple limbal epithelial transplantation (G-SLET) or simultaneous G-SLET and lamellar keratoplasty. Patients with bilateral LSCD with normal or increased corneal thickness were enrolled in the paralimbal oral mucosa epithelium transplantation (pLOMET) clinical trial. Conclusions: Based on the diagnostic and surgical data analyzed, the key points in LSCD diagnosis were identified, helping to guide the surgeon in selecting the appropriate surgical procedure. Finally, we proposed a novel step-by-step diagnostic algorithm and original surgical guidelines for the treatment of patients with LSCD.

Purpose: We recently showed the positive clinical effects of combining accelerated corneal cross-linking (PACK-CXL) with antibiotic treatment in patients with presumed bacterial keratitis. In this study, we compare the impacts of a combined PACK-CXL/standard antibiotic treatment (PACK-ABX group) with standard antibiotic treatment alone (ABX group) in patients with culture-confirmed bacterial keratitis. Methods: We reviewed patients with moderate and severe bacterial keratitis and confirmed bacterial cultures. Clinical outcomes were compared for standard antibiotic treatment alone, before the initiation of PACK-CXL, and after adjuvant use of PACK-CXL. Results: A total of 47 eyes of 47 patients were included: 26 eyes in the PACK-ABX group and 21 eyes in the ABX group. Pathogens, baseline demographics (besides age), and clinical parameters were similar between the 2 groups. The PACK-ABX patients had better final uncorrected visual acuity [mean difference 0.57 Logarithm of the Minimum Angle of Resolution, 95% Confidence Interval (CI): 0.16–0.99, P = 0.07] and best-corrected visual acuity (mean difference 0.70 Logarithm of the Minimum Angle of Resolution, 95% CI: 0.23–1.16, P = 0.04), shorter reepithelialization time (mean difference 9.63 days, 95% CI: 3.14–16.12, P = 0.004), and reduced number of clinic visits (mean difference 4.8 meetings, 95% CI: 1.4–8.2, P = 0.007) and need for tectonic grafts (0 vs. 33.3%, P = 0.002). A multivariate analysis controlling for age, sex, ulcer size, and Gram stain showed that PACK-ABX treatment remained significantly associated with reepithelialization time (β = 14.5, P = 0.001). Conclusions: In our study, PACK-CXLs addition to the standard of care in cases of culture-proven bacterial keratitis had a positive effect on the final visual acuity and time to resolution, compared with the standard-of-care treatment.

Advancements in surgical techniques and increased life expectancy have made cataract surgery more common among very old patients. However, surgical outcomes seem impaired in patients older than 90 years, especially with ocular comorbidities. A retrospective case-control study of 53 eyes of 53 very old patients (mean 92.6 ± 3.0) and 140 eyes of 140 matched patients (mean 75.2 ± 7.6) was undertaken. Groups were matched in terms of gender and systemic and ocular comorbidities. In very old patients, higher phacoemulsification energy (cumulative dissipated energy [CDE], 25.0 ± 22.4 vs. 16.1 ± 10.7, p = 0.01) and rate of intraoperative floppy iris syndrome (IFIS, 9.4% vs. 1.4%, p = 0.02) were observed compared to controls. Uncorrected (UCVA) and best-corrected distance visual acuity (BCVA) gains were significantly poorer among the very old patients than among the control at postoperative day 30 (0.20 ± 0.70 vs. 0.56 ± 0.61 logMAR, p < 0.001 and 0.27 ± 0.64 vs. 0.55 ± 0.62 logMAR, p = 0.006, respectively). Even after including CDE and IFIS as covariates, age remained an independent factor for poor visual gain at 30 days (p < 0.001). Cataract surgery in very old patients may demand more experienced surgeons due to higher nuclear density and the rates of IFIS. Expectations in visual acuity gains should be aligned with the patient’s age.