Axial length and pharmacologic pupillary dilation in highly myopic patients.

PURPOSE: To determine how high myopia impacts pharmacological pupillary dilation, and to evaluate the relationship between the extent of pharmacologic pupillary dilation and axial length. METHODS: Patients were grouped into high myopes, defined as one or both eyes having a refractive error greater than - 6 diopters, and controls (between - 2 and + 2 diopters). Dilation was achieved with 1 drop each of tropicamide 1% and phenylephrine 2.5%. Pupil size was measured at full and dim light prior to dilation, then 15 and 30 min after dilation. Biometry was measured for each patient. Statistical analyses were performed using the Mann-Whitney-Wilcoxon tests, two-sample Welch's t-tests, and linear mixed effect models and generalized estimating equations models accounting for inter-eye correlation. RESULTS: Forty patients (20 high myopes and 20 controls, 80 eyes total) participated in the study. High myopes had larger pupils at baseline and achieved significantly greater pupillary size (7.08 mm, 95% CI: 6.97 to 7.19 mm) than controls (6.23 mm, 95% CI: 5.94 to 6.52 mm) after 30 min of dilation (P < .0005). Fully dilated pupil size at 30 min was significantly correlated with both refractive error (r = - 0.57, P < .0005) and axial length (r = 0.47, P < .0005). Generalized estimating equations and linear mixed effect models identified other predictive variables of pupil size after dilation including age and white-to-white diameter. CONCLUSIONS: Highly myopic patients dilate to a larger pupillary size compared to other patients. Predicting dilation based on extent of myopia could facilitate intraocular surgery planning and reduce clinic wait times for myopic patients.

Corneal pseudoectasia: a case series.

OBJECTIVE: To raise awareness of conditions that can tomographically mimic corneal ectasia and describe the actions required to avoid misdiagnosis. METHODS: We report a retrospective case series of seven patients presenting at two tertiary care centers in Israel with a presumed diagnosis of keratoconus or post-refractive ectasia. Upon further examination, the ectasia diagnosis was reconsidered and eventually ruled out. RESULTS: Included were ten eyes of seven patients. Cases included bilateral diffuse Salzmann's nodular degeneration, ophthalmoplegia with strabismus which precluded proper fixation during the acquisition of tomography images, two cases of incorrect Pentacam parameter settings, a patient with a history of hyperopic laser-assisted in situ keratomileusis (LASIK) treatment in one eye and myopic LASIK in the fellow eye, a case of old post-photorefractive keratectomy (PRK) stromal haze, and a patient with posterior polymorphous corneal dystrophy. CONCLUSIONS: Tomography patterns mimicking corneal ectasia can appear in patients without ectatic pathology. The comprehensive ophthalmologist should be aware of such cases as they may substantially alter the treatment course and prognosis of these patients.

[ARTIFICIAL CORNEA: FROM THE BEGINNING TO THE FUTURE].

INTRODUCTION: Corneal disease is among the leading reversible causes of blindness worldwide. Corneal transplantation is a successful and curative treatment for most of these cases. However, in certain indications it is not amendable for standard corneal transplantation, the only available option to restore functional vision is keratoprosthesis (KPro) implantation. KPros may also offer an alternative to the global shortage of donor corneas, limiting the access to transplantations. However, current KPros face many challenges, including surgical complexity that requires skilled surgeons and vast resources as well as unique surgical and post-operative complications. Although several artificial corneas have been proposed over the years, two implants are mostly used in the clinical setting today. The first, the Boston KPro, consists of a front plate with an optical stem and a back plate snapped together with donor corneal tissue in-between, which is then sutured to the patient's cornea. The second, the Osteo-odonto-keratoprosthesis (OOKP), uses biological tissue of the alveolar bone to support an optical cylinder within the eye. The indications, surgical techniques, and complication profile of the two procedures are different and will be discussed in this review. Extensive research continues to improve the accessibility and technological developments of KPros in the search for a potential breakthrough in the treatment of these difficult cases.

Validation of the multi-metric D-index change in the assessment of keratoconus progression.

PURPOSE: To validate the effectiveness of the multi-metric D-index by Pentacam in detecting keratoconus (KC) progression. MATERIALS AND METHODS: This was a retrospective study of KC patients at the Rabin Medical Center, Petah Tikva, Israel, during 2016-2018 with at least two corneal tomography examinations six months apart. Agreement between clinical diagnosis of progression (1.5D increase in mean keratometric value, 1D increase in Kmax, a 5% decrease in central corneal thickness (CCT), worsening of visual acuity by more than one line, or deterioration of manifest corneal astigmatism > 1.5D) and the D-index was evaluated. Receiver operating characteristic (ROC) analysis was used to find the D-index's optimal cutoff value to show progression. RESULTS: We included KC eyes in the stable group (N = 7) and the progression group (N = 54). Patient demographics and tomographic parameters at baseline were similar between the groups. The D-index change was significantly higher in the progression group than in the stable group (median + 1 and 0.0, respectively, p = 0.024). Based on the ROC analysis, the optimal D-index cutoff change within at least six months was 0.32 (59.3% sensitivity and 100% specificity (area under the curve [AUC] = 0.771, Youden = 0.592). Subjects with a D-index change above this value had a 21.1-fold increase in odds for corneal ectasia progression requiring CXL (OR: 21.1, 95%CI 1.17-398.8, p = 0.038). CONCLUSION: The multi-metric D-index can serve as a clinically feasible parameter to detect KC progression and guide patients' referral for further interventions.

Subconjunctival Aflibercept for the Treatment of Formed Corneal Neovascularization.

PURPOSE: To evaluate the effect of a single subconjunctival aflibercept injection on formed corneal neovascularization. METHODS: A prospective clinical trial, conducted at a single tertiary medical center. Included were consecutive patients with corneal pathologies complicated by corneal neovascularization, who were candidates for anti-vascular endothelial growth factor treatment at the discretion of a cornea specialist. A single subconjunctival injection of 0.08 mL of Aflibercept (Eylea 25 mg/mL) was administered near the limbus in proximity to the areas of maximal pathological neovascularization. Follow-up visits were scheduled on days 7, 30, 60, and 90 following injection. Best-corrected visual acuity (BCVA), intraocular pressure, slitlamp examination, digital cornea photography, specular microscopy, and anterior-segment optical coherence tomography were documented at each visit. The images were graded by a masked observer for density, extent, and centricity of corneal vascularization. RESULTS: Six eyes of six patients were analyzed. No clinically significant ocular or systemic adverse events were documented. No change was noted in extent, density, or centricity of corneal blood vessels at seven, 30, and 90 days after injection (P>0.1 for all time point comparisons, Friedman test). Best-corrected visual acuity fluctuated insignificantly in 5/6 patients during follow-up time, and objective but not subjective improvement of BCVA was noted in one patient with no concurrent change of neovascularization. The recruitment has therefore halted prematurely. CONCLUSIONS: A single subconjunctival aflibercept injection seems to be well tolerated. However, it is ineffective for regressing formed corneal neovascularization.

Outcomes of Repair of Total Graft Detachment following Descemet's Membrane Endothelial Keratoplasty. / Rettungsversuche einer vollständigen Transplantatablösung nach Descemet-Membran-Endothelkeratoplastik.

OBJECTIVE: To present the outcomes of attempts to salvage total graft detachment following Descemet's membrane endothelial keratoplasty (DMEK). METHODS: A search of the electronic medical records of two tertiary medical centers for all patients who underwent DMEK yielded six cases of postoperative total graft detachment (2.54%). Graft salvage was attempted in all cases using repeated intracameral graft staining, unfolding, and reattachment to the stroma under 20% hexafluoride gas. RESULTS: In all cases, a free-floating totally detached graft was identified in the anterior chamber shortly after surgery. Salvage surgery resulted in a central, well-oriented, and fully attached graft. In three cases, the primary graft failed, and in two, the corneas cleared at first but failed after 2 months and 1 year respectively. In one case, the cornea remained clear during 1 year of follow-up but had a very low endothelial cell density. CONCLUSION: Reattachment of fully detached DMEK graft is technically possible, but graft manipulation during the primary and secondary operations is likely to damage the endothelial cells, resulting in primary or early graft failure. If graft salvage is attempted, the probability of primary or early graft failure should be discussed with the patient, and expectations should be tempered accordingly.

Refractive outcomes following cataract combined with lamellar keratoplasty: femtosecond-DSEK versus microkeratome-DSAEK.

PURPOSE: Prediction of postoperative refraction following posterior lamellar keratoplasty is crucial for choosing proper intraocular lens power in combined surgeries. Femtosecond laser-assisted Descemet stripping endothelial keratoplasty (FS-DSEK) creates thin, planar grafts while microkeratome-assisted Descemet's stripping automated endothelial keratoplasty (DSAEK) creates non-planar, concaved grafts. We evaluated whether this fundamental difference affects the refractive outcomes in cataract surgery combined with FS-DSEK compared to cataract surgery combined with microkeratome-assisted DSAEK. METHODS: A retrospective analysis of 28 patients who underwent FS-DSEK combined with phacoemulsification and intraocular lens (IOL) implantation (group A) compared to 26 patients who underwent microkeratome-assisted DSAEK combined with phacoemulsification and IOL implantation (group B). Pre- and 1-year postoperative best-corrected visual acuity (BCVA), keratometry values, corneal thickness, central-to-peripheral graft thickness ratio (C/P ratio), and target postoperative spherical equivalent (SE) versus actual postoperative SE were analyzed. RESULTS: Target postoperative SE and actual postoperative SE significantly shifted toward hyperopia in group B, but not in group A. Postoperative hyperopic shifts were 0.14 D and 1.13 D in groups A and B, respectively (P < 0.001). BCVA improved after surgery in both groups, with no significant difference between the groups. Postoperative C/P ratio differed significantly between the groups and was negatively correlated with postoperative hyperopic shift (r = - 0.616, P < 0.001). CONCLUSION: Refractive outcomes of cataract surgery combined with FS-DSEK are relatively neutral, whereas those of cataract surgery combined with microkeratome-assisted DSAEK cause significant hyperopic shift. Clinicians should select accordingly an appropriate intraocular lens power when performing these surgeries.

PATIENTS WEARING FACE MASKS DURING INTRAVITREAL INJECTIONS MAY BE AT A HIGHER RISK OF ENDOPHTHALMITIS.

PURPOSE: To investigate the safety of face masks worn by patients during intravitreal injections. METHODS: A prospective, qualitative, interventional study performed in a tertiary university hospital. Healthy volunteers were asked to wear three different professional surgical face masks while air leaks around the eyes were monitored. Three types of masks were investigated as follows: 1) surgical face mask with four tying strips, 2) surgical face mask with elastic ear loops and 3) 2200 N95 tuberculosis particulate face mask. For each session the periocular area was inspected for air leak during normal respiration, speech, and deep respiration. Detection of air leak was performed using the following two professional thermal cameras: FLIR A310-thermal camera and EyeCGas 2.0-super sensitive infrared camera used for detection of minute fugitive emissions of industrial gases. RESULTS: Ten healthy volunteers were enrolled in this study. The experiment was repeated 45 times for each camera; 3 times for each of 3 mask types, on 5 volunteers, for a total of 90 trials. Air jets were detected originating from the superior edges of the masks radiating toward the eyes in 81% (73/90) of cases in total; 71% (32/45) with the FLIR camera and 91% (41/45) with the OPGAL camera. Air leaks were detected with all investigated mask types. CONCLUSION: Patients wearing face masks during intravitreal injections may be at a higher risk of endophthalmitis. Until further data are available, we recommend verifying proper face mask fitting and either taping the upper edges of the face masks with a medical adhesive tape or using an adhesive surgical drape around the injected eye.

Is Performing Femtosecond Laser-Assisted In Situ Keratomileusis on the Day of the Initial Consultation Visit Safe, Predictable and Efficacious?

OBJECTIVES: Our aim is to evaluate the safety, efficacy, predictability, and clinical outcome of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) procedures performed on the day of the initial consultation relative to procedures performed at subsequent visits. METHODS: A retrospective cohort study design was used. The study group included patients with myopia of different severities who were treated with FS-LASIK in 2013 through 2014 in an optical outpatient clinic of a large private medical service. Inclusion criteria were at least 18 years of age, a stable refraction for 12 months, no history of autoimmune disease, ocular surgery, or eye disease, and complete medical records. Background, clinical, and outcome data were collected from the patient files. RESULTS: Femtosecond laser-assisted in situ keratomileusis was performed in 80 patients (160 eyes) at the first visit and 361 patients (719 eyes) at a subsequent visit. The mean±SD spherical equivalent (SE) refraction before surgery was -3.74±2.03 D in the first-visit group and -3.73±1.87 D in the subsequent-visit group (P=0.99). Efficacy index values were 0.97±0.15 in the first-visit group and 0.98±0.13 in the subsequent-visit group (P=0.92), and corresponding safety index values were 0.99±0.15 and 0.99±0.12 (P=0.81). The final SE measured -0.09±0.58 D in the first-visit group and -0.19±0.55 D in the subsequent-visit group (P=0.05). Types and rates of complications were similar in the two groups. CONCLUSIONS: There is no significant difference in the results of refractive surgery with FS-LASIK between procedures performed at the initial or subsequent visits. In both conditions, FS-LASIK surgery is associated with excellent safety, efficacy, and predictability profiles.

Comparative analysis of biomechanical parameters of the corneas following Descemet membrane endothelial keratoplasty and contralateral healthy corneas.

PURPOSE: To compare the biomechanical properties of the unilateral operated corneas in patients who had undergone Descemet membrane endothelial keratoplasty (DMEK) for pseudophakic bullous keratopathy (PBK) with those of the contralateral normal corneas. METHODS: This was a retrospective cohort study conducted at university hospitals (Department of Ophthalmology, Rabin Medical Center, Petach Tikva, Israel, and S. Fyodorov Eye Microsurgery State Institution, Moscow, Russia). Forty eyes of 20 patients who underwent DMEK for unilateral PBK 3.5 to 36 months ago and with normal fellow eyes were included in the study. An ocular response analyzer was used to measure the corneal biomechanical properties in the operated and normal fellow eyes. The main outcome measures were corneal hysteresis (CH) and corneal resistance factor (CRF). RESULTS: The mean CH (8.4 ± 1.5 mmHg vs. 8.2 ± 1.5 mmHg, P = 0.707) and the mean CRF (8.7 ± 1.6 mmHg vs. 8.3 ± 1.6 mmHg, P = 0.419) values did not show any statistically significant difference between the operated and the normal fellow eyes. CONCLUSIONS: In our study, the corneas that underwent DMEK for PBK showed normal values for biomechanical parameters. These findings support the previous studies that have reported near complete visual, functional, and ultra-structural rehabilitation of the corneas following DMEK.

Comparison of Subconjunctival Aflibercept and Betamethasone for the Treatment of Formed Corneal Neovascularization in a Rabbit Model.

AIM: To compare the efficacy of aflibercept (Eylea®), a potent antivascular endothelial growth factor (VEGF) agent, with betamethasone (Celestone®) and placebo for the treatment of formed corneal neovascularization in a rabbit model. METHODS: A central corneal chemical burn was created in the right eye of 24 New Zealand albino rabbits. Four weeks later, the rabbits were randomly divided into 4 equal groups for subconjunctival injection of aflibercept, betamethasone, aflibercept+ betamethasone, or saline (control). Digital photographs taken at weekly intervals were rated by 2 masked observers for extent, centricity, and density of corneal neovascularization according to a predefined scale. The percentage of corneal surface involved by neovascularization was quantified by image analysis software (Fiji-J). The change in corneal neovascularization from treatment administration (4 weeks after injury) to 4 weeks later (8 weeks after injury) was assessed. The rabbits were then euthanized, and their eyes were enucleated and processed for histopathological and immunofluorescence studies. RESULTS: There was no significant difference in the change in corneal neovascularization after treatment among the 4 groups according to the digital images (p > 0.15) or histological evaluation with hematoxylin and eosin (p > 0.08). On immunofluorescence assay, a lower VEGF concentration was observed in all treatment groups compared to the control group. CONCLUSIONS: In this rabbit model, corneal neovascularization induced by chemical burn failed to regress with treatment with aflibercept, betamethasone, or their combination.

Research productivity across different ophthalmic subspecialties in the United States.

BACKGROUND: The purpose of this study was to compare the h-index, and subsequently the research productivity, among different ophthalmic subspecialties in the United States. METHODS: A cohort of over 15,000 academic ophthalmologists residing in the United States (US) was identified out of the physician list of the American Academy of Ophthalmology. Of them, 1000 ophthalmologists with at least one publication were randomly retrieved, 100 in each of the following 10 subspecialties: cataract, cornea/external disease, glaucoma, medical retina, neuro-ophthalmology, pediatric ophthalmology, plastic/reconstructive ophthalmology, refractive surgery, retina/vitreous surgery and uveitis. Data collected included: number of published papers, h-index score, annual increase in h-index and the mean number of authors on each paper. RESULTS: The mean h-index amongst all subspecialties was 9.87 ± 13.90, and the mean average annual increase in h-index was 0.22 ± 0.21. The mean number of papers published was 37.20 ± 80.08 and the mean number of authors on each paper was 3.39 ± 0.84. Uveitis was the most prolific subspecialty in mean number of papers (74.78 ± 131.37), in mean h-index (16.69 ± 20.00) and in mean annual increase in h-index (0.35 ± 0.28). The least fertile subspecialty with regards to research was cataract with 11.06 ± 27.65 mean number of papers, a mean h-index of 3.89 ± 5.84, and a mean annual increase in h-index of 0.11 ± 0.11. CONCLUSIONS: This study describes the research productivity in each ophthalmic subspecialty in the US, thus providing information on the research performance of each field and on the expected academic accomplishments within it.

Corneal Endothelial Decompensation after Ocular Chemical Burn: Description of a New Finding.

BACKGROUND: Ocular chemical burn is an ophthalmological emergency. Therefore, chemical injuries should be promptly addressed in order to initiate the appropriate treatment as soon as possible and optimize the visual prognosis. We present a retrospective study of ten cases with ocular chemical burn including one with superglue and one with a liquid plaster material injury and describe their clinical course. HISTORY AND SIGNS: Ten adult patients (34 - 92 years, 8 males) presented with moderate to severe alkali or neutral chemical burns in our emergency clinics. They exhibited a variable degree of conjunctival injection, limbal ischemia, corneal erosion, and Descemet's folds. THERAPY AND OUTCOME: Patients were treated and complete corneal epithelial closure was achieved in all cases without significant signs of limbal stem cell insufficiency. Corneal endothelial insufficiency was observed in all cases. Nine patients had to be listed for corneal endothelial keratoplasty and one was treated with Descemet's stripping endothelial automated keratoplasty. CONCLUSIONS: Isolated corneal endothelial decompensation after chemical burns has not yet been described. The pathophysiological explanation of this observation remains, however, unknown. In view of this rare complication, it is important to follow patients after chemical ocular burn for possible development of endothelial decompensation.

Z-LASIK and Trans-PRK for correction of high-grade myopia: safety, efficacy, predictability and clinical outcomes.

PURPOSE: The aim of the study was to examine the outcomes of transepithelial photorefractive keratectomy (Trans-PRK) and Femtosecond Laser-assisted in situ keratomileusis (Z-LASIK) for the correction of high myopia. METHODS: A retrospective cohort study design was used. The study group included 792 eyes with high-grade myopia (- 6.0 diopters or higher) or high-grade myopia with astigmatism that were treated with Z-LASIK or Trans-PRK in 2013 through 2014 in an optical outpatient clinic of a large private medical service. The Trans-PRK group comprised of 674 eyes with a spherical equivalent (SE) of - 7.87 ± 1.46 and the Z-LASIK group comprised of 118 eyes with a SE of - 7.19 ± 0.81 (P < 0.001). RESULTS: The mean postoperative SE in the Trans-PRK group was - 0.06 and - 0.02 in the Z-LASIK group (P = 0.545). Efficacy index values were 0.92 in the Trans-PRK group and 0.95 in the Z-LASIK group (P = 0.083), and corresponding safety index values were 0.95 and 0.97 (P = 0.056). An UCVA of 20/40 or better was achieved in 94.20% of eyes in the Trans-PRK group, and 98.31% in the Z-LASIK group (P = 0.063). The majority of eyes in both the Trans-PRK and Z-LASIK groups were within ± 0.5D of attempted correction: 59.35 and 64.71%, respectively (P = 0.271). CONCLUSIONS: Both Trans-PRK and Z-LASIK demonstrated excellent efficacy, safety and predictability profiles, with results comparable and in some cases superior to the current literature. Results of Z-LASIK were slightly better than those of Trans-PRK, though the preoperative SE of the latter was higher.

[PREVALENCE OF DEMODEX PARASITES IN PATIENTS WITH CHRONIC BLEPHARITIS AND HEALTHY CONTROLS IN ISRAEL].

INTRODUCTION: Previous studies demonstrated the potential pathogenic relationship between infestation of the eyelashes by the parasite Demodex and chronic blepharitis, whereas other studies did not demonstrate such relations and concluded that Demodex is a normal eyelid flora. AIMS: This study examines the prevalence of Demodex in patients with blepharitis compared to a healthy control group in Israel, in order to further explore and establish its pathogenic role in cases of chronic blepharitis. METHODS: A case-control study was conducted including 110 participants: 60 patients with chronic blepharitis attending a tertiary medical center and 50 subjects with no signs of blepharitis. Six to eight eyelashes were epilated from each participant and studied microscopically for the presence of Demodex by a blinded examiner. Fluorescein stain was added to the "clean" samples in order to reduce the false negative results. RESULTS: Demodex were identified on the eyelashes of 44 patients with blepharitis (73.3%) and 20 controls (40%) (p<0.001). After adjusting for age, blepharitis was still a significant risk factor for the presence of Demodex (OR=2.96, CI 95% 1.2-7.3). CONCLUSIONS: This study supports previous studies demonstrating pathogenic relationship between Demodex infestation of the eyelashes to chronic blepharitis. The authors recommend epilating 6-8 lashes of patients with blepharitis for microscopic identification of these parasites. Fluorescein stain may have a limited role in the recognition of Demodex in parasite free samples.

'Blue bubble' technique: an ab interno approach for Descemet separation in deep anterior lamellar keratoplasty using trypan blue stained viscoelastic device.

BACKGROUND: In this study, we examined a novel variant of 'big-bubble' deep anterior lamellar keratoplasty using trypan-blue-stained viscoelastic device for the creation of a pre-descemetic bubble. METHODS: Ten corneoscleral rims were mounted on an artificial anterior chamber (AC). The AC was filled with air through a limbal paracentesis. A Melles' triangulated spatula was inserted through the paracentesis, with its tip penetrating the AC, was then slightly retracted and pushed into the deep stroma above the roof of the paracentesis. A mixture of trypan blue and viscoelastic device (Healon, Abbott Medical Optics, Abbott Park, Illinois) was injected into this intra-stromal pocket using a 27-G cannula to create a pre-descemetic separation bubble. Bubble type and visualization of dyed viscoelastic device were noted. The method was later employed in three cases. RESULTS: In all 10 corneoscleral rims, the technique successfully created a visible pre-descemetic (type 1) bubble that could be expanded up to the predicted diameter of trephination. Subsequent trephination and the removal of corneal stroma were uneventful. In two out of four clinical cases, a type 1 bubble was created, while in two others, visco-dissection failed and dyed viscoelastic was seen in the AC. CONCLUSIONS: The presented technique holds promise of being a relatively easy to perform, predictable and well-controlled alternative for achieving a type 1 bubble during deep anterior lamellar keratoplasty surgery. The trypan-blue-stained viscoelastic device facilitates proper visualization and control of the separation bubble and assists in identifying the penetrance to the separation bubble prior to removal of the stromal cap.

Corneal melting in rheumatoid arthritis patients treated with a tectonic reinforcing corneolimbal graft: an interventional case series.

PURPOSE: Corneal melting with perforation is a severe ophthalmic complication of autoimmune disorders such as rheumatoid arthritis. It requires urgent medical management in order to maintain the integrity of the globe and preserve vision. Treating this complication by penetrating keratoplasty is problematic due to the high rate of recurrence of corneal melting as well as other complications. We describe the use of a tectonic fresh-tissue corneolimbal covering graft. METHODS: An interventional case series including three patients that presented to our tertiary center between 2000 and 2015 with corneal melting and perforation, secondary to rheumatoid arthritis. Emergency surgery included suturing of a 13.00- to 13.50-mm full-thickness fresh-tissue corneolimbal covering graft to the patient's posterior limbal zone. RESULTS: The corneolimbal graft maintained the integrity of the cornea in all cases, by sealing the perforation and promoting the creation of a fibrovascular scar at the area of corneal melting. There were no complications, recurrences of host corneal melting, or perforation during the follow-up period. CONCLUSION: Fresh-tissue full-thickness corneolimbal grafts may be used to cover emergency corneal melting and perforations secondary to rheumatoid arthritis.

Efficacy of topical aflibercept versus topical bevacizumab for the prevention of corneal neovascularization in a rat model.

The aim of this experimental study was to compare the efficacy of topical aflibercept and topical bevacizumab in preventing corneal neovascularization. A chemical burn was created in the right central cornea of male Sprague-Dawley rats, followed immediately by instillation of one drop (25 mg/ml, 20 µl volume) of aflibercept (15 eyes), bevacizumab (14 eyes), or saline (15 eyes). Treatment was repeated twice daily for 7 days. Corneal neovascularization was determined using corneal photographs (ImageJ) on days 1, 4, 7, 10, and histological and immunofluorescence studies, on day 10. Stromal immunoreactivity was evaluated 2 days after injury in 6 rats treated singly with bevacizumab or aflibercept. Corneal neovascularization was observed clinically on day 4 in all groups. In the aflibercept group, the area of neovascularization increased from 7.38 ± 2.23% on day 4 to 21.73 ± 14.59% on day 7 and 31.0 ± 23.61% on day 10. Corresponding values in the bevacizumab group were 6.04% ± 1.81%, 51.27 ± 15.50%, and 54.4 ± 11.33%, and in the control group, 8.99 ± 1.93%, 42.6 ± 19.59%, and 55.15 ± 11.54%. The area of neovascularization was significantly smaller on days 7 and 10 in the aflibercept group than in the control and bevacizumab groups (P < 0.001, all analyses), with no significant differences between the latter two groups (day 7, P = 0.868; day 10, P = 0.213). Clinical findings were compatible with the histological data and supported by immunofluorescence and corneal flat-mount staining. Both drugs demonstrated variable penetration into the corneal stroma. Topical aflibercept effectively inhibits corneal neovascularization in a rat model of chemical burn. These findings may have important therapeutic implications for humans.

Repeatability and intrasession reproducibility obtained by the Sirius anterior segment analysis system.

OBJECTIVE: To analyze repeatability and intrasession reproducibility of anterior segment measurements using the newly developed Sirius Scheimpflug system. METHODS: Three consecutive measurements on 100 eyes of 50 healthy subjects were performed on the same session by the same technician using the Sirius device at the Assuta Optic Laser Center, Tel-Aviv, Israel. For each eye, the following parameters were measured: anterior chamber angle (ACA), anterior chamber volume (ACV), and anterior chamber depth (ACD), thinnest corneal location, keratometry (anterior and posterior), cylinder, and axis. Repeatability was assessed using the coefficient of variation (CV). Intrasession reproducibility was assessed using intraclass correlation coefficient (ICC). RESULTS: Coefficient of variation of 2% and less was observed for ACA, ACD, thinnest corneal location, and anterior keratometry. Intraclass correlation coefficients were high for ACA, ACD, anterior keratometry measurements and moderate for anterior cylinder and axis. Higher CV with relatively low ICC values was noticed with ACV, posterior keratometry measurements, and posterior cylinder, and axis. The last 2 have the highest CV and lowest ICC: 48.79% (range: 37.64%-59.95%) and 0.38%, respectively. CONCLUSIONS: The Sirius Scheimpflug system has a very high repeatability and intrasessional reproducibility when measuring the ACD, ACA, anterior curvature parameters, and the thinnest corneal location. Thus, it can be used with confidence in clinical practice.

Efficacy comparison of combining cross-linking and refractive laser ablation in progressive keratoconus: systematic review and meta-analysis.

OBJECTIVE: This study assessed the effect of combining corneal collagen cross-linking (CXL) with refractive laser ablation techniques for the treatment of keratoconus, a progressive corneal disorder. METHODS: We performed a systematic review and meta-analysis to assess the effect of combined CXL and refractive techniques. We included all published clinical trials or observational studies published by September 1, 2023. We calculated and compared the standardized mean difference (SMD) between CXL alone and CXL plus laser ablation for uncorrected distance visual acuity, best-corrected distance visual acuity, spherical equivalent manifest refraction, sphere and cylinder, flat keratometry (K1), steep keratometry (K2), and central corneal thickness. RESULTS: We identified 13 studies that fulfilled our inclusion and exclusion criteria. The average follow-up was 21.3 ± 11.8 months. The CXL plus laser ablation group showed improvement in uncorrected distance visual acuity logMAR (SMD, -0.35; 95% CI, -0.67 to -0.04; p = 0.029), best-corrected distance visual acuity logMAR (SMD, -0.17; 95% CI, -0.30 to -0.03; p = 0.014), spherical equivalent manifest refraction (SMD, -0.28; 95% CI, 0.06-0.50; p = 0.013), and change in maximal corneal curvature (Kmax; SMD, -0.41; 95% CI, -0.69 to -0.13; p = 0.004) compared with CXL alone. However, central corneal thickness decreased further among patients who underwent CXL plus laser ablation (SMD, -0.37; 95% CI, -0.66 to -0.07; p = 0.016). No effect was observed in terms of sphere (p = 0.878), cylinder (p = 0.859), K1 (p = 0.907), or K2 (p = 0.169). Ectasia was not observed as an adverse effect resulting from the additional corneal ablation performed during the CXL treatments. CONCLUSIONS: This study showed that combining refractive laser ablation techniques with standard or accelerated CXL treatment improved visual and refractive outcomes and anterior corneal curvature values.