Mehdi Shajari

Early growth response-1 induction by fibroblast growth factor-1 via increase of mitogen-activated protein kinase and inhibition of protein kinase B in hippocampal neurons

Background and purpose:  The transcription factor early growth response‐1 (Egr‐1) and the acidic fibroblast growth factor (FGF‐1) are involved in many regulatory processes, including hippocampus‐associated learning and memory. However, the intracellular signalling mechanisms regulating Egr‐1 in hippocampal cells are not entirely understood.

Keratometry versus total corneal refractive power: Analysis of measurement repeatability with 5 different devices in normal eyes with low astigmatism.

Purpose To analyze the repeatability of corneal astigmatism measurements with 2 autokeratometers (IOLMaster 500 and Lenstar LS 900), 2 Placido topographers (Keratron Scout and Atlas 9000), and a Scheimpflug tomographer (Pentacam HR). Setting Department of Ophthalmology, Goethe University, Frankfurt, Germany. Design Prospective case series. Methods The inclusion criteria were a minimum age of 18 years, corneal astigmatism of 3.00 diopters or less, and patient’s consent to participate in the study. The main exclusion criteria were corneal pathologies, trauma, previous surgery, hard contact lens wear in the previous 3 months, and soft contact lens wear in the previous 6 weeks. In addition to manifest refraction and visual acuity measurements, all subjects had 2 full measurements of 1 eye using each device. Anterior corneal astigmatism and total corneal refractive power via calculations derived from the Scheimpflug tomographer were evaluated. Statistical analysis was performed using the Bland‐Altman method and multiple linear regression analysis. Results Forty‐five eyes of 45 subjects (mean age 53.11 years ± 10.43 [SD]; 23 left eyes; 33 women) were included. The mean intermeasurement differences were approximately zero for all devices. The relative coefficient of repeatability of anterior corneal astigmatism, steep axis, and the vector analysis parameter J180 were lowest with the Scheimpflug tomographer. Total corneal refractive power measured with the Scheimpflug tomographer showed the highest repeatability in the larger diameter zones. Conclusion The Scheimpflug tomographer yielded higher repeatability of corneal astigmatism measurements, with total corneal refractive power measurements being as repeatable as established metrics. Financial Disclosure Dr. Kohnen receives research support from Abbott Medical Optics Inc., Alcon Pharma GmbH, Bausch & Lomb GmbH, Carl Zeiss Meditec Vertriebsgesellschaft mbH, Hoya Surgical Optics GmbH, Oculus Optikgeräte GmbH, and Schwind eye‐tech‐solutions GmbH and Co. KG. He receives travel reimbursement, lecture fees and is a consultant to Abbott Medical Optics Inc., Alcon Pharma GmbH, Carl Zeiss Meditec Vertriebsgesellschaft mbH, Geuder AG, Oculus Optikgeräte GmbH, Schwind eye‐tech‐solutions GmbH and Co. KG, TearLab Corp., Thieme Compliance, and Ziemer Ophthalmic Systems AG. None of the other authors has a financial or proprietary interest in any of the materials or methods mentioned.

Comparison of Corneal Diameter and Anterior Chamber Depth Measurements Using 4 Different Devices.

Purpose: To evaluate the reliability and validity of anterior chamber depth (ACD) and corneal diameter [white-to-white (WTW) distance] measurements with 4 devices as well as applicability of these values in predicting the anterior chamber angle diameter evaluated by optical coherence tomography for implantation of lenses in the anterior chamber. Methods: In this prospective randomized case series, we measured ACD and WTW distance in one eye of 40 healthy subjects with Pentacam HR, IOL Master 500, LenStar 900, and Visante OCT. Results: When comparing WTW distance with anterior chamber angle diameter measured by Visante OCT coefficient of repeatability and limits of agreement ranges were 0.5 and 1.1 mm for IOL Master, 0.5 and 1.1 mm for Pentacam HR, and 0.6 and 1.1 mm for LenStar (P < 0.05 in all cases), respectively. Coefficient of repeatability and limits of agreement ranges were 0.3 and 0.6 mm for IOL Master, 0.3 and 0.5 mm for Pentacam HR, and 0.3 and 0.6 mm for LenStar, respectively, compared with ACD measured by Visante OCT; however, P was not significant in any of the cases. P value was also not significant when comparing IOL Master, LenStar, and Pentacam in terms of ACD and WTW distance with each other. Conclusions: Unlike previous groups analyzing the ACD and WTW distance we found no significant difference between the measurements by different automatic devices. We consequently expect no difference in clinical outcome when measurements for WTW distance or ACD are performed with any of the devices listed above.

Meta-analysis of Postoperative Outcome Parameters Comparing Descemet Membrane Endothelial Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty

Purpose: This meta-analysis compares Descemet membrane endothelial keratoplasty (DMEK) with Descemet stripping automated endothelial keratoplasty (DSAEK) to evaluate their strength and weakness profiles. Design: Meta-analysis. Methods: We performed a meta-analysis and searched the peer-reviewed literature in PubMed, Cochrane Library, Web of Science, and Embase following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Prospective and retrospective trials performing and comparing DMEK and DSAEK were included. Effects were calculated as odds ratios or standardized mean differences. Results: A total of 11 studies with a total of 723 eyes (350 DMEK and 373 DSAEK) were included. No significant difference was found regarding the total detachment rate, graft failure, and rejection. One of 340 eyes undergoing DMEK showed total detachment and 5 of 363 eyes undergoing DSAEK showed total detachment (P = 0.28). Six of 280 eyes undergoing DMEK showed graft failure; 1 of 313 eyes undergoing DSAEK developed this complication (P = 0.18). No rejection was observed in 158 eyes undergoing DMEK; 4 cases of rejection occurred in 196 eyes undergoing DSAEK (P = 0.37). No significant difference was found regarding endothelial cell loss (P = 0.48). There was a significantly higher partial detachment rate with DMEK: 88 of 340 eyes undergoing DMEK showed partial detachment; 16 of 363 eyes undergoing DSAEK showed this complication (P < 0.00001). DMEK was superior in best-corrected visual acuity after 6 months (P < 0.001), subjective evaluation of visual acuity (P = 0.001), patient satisfaction (P < 0.001), and was the method preferred by patients (P = 0.001). Conclusions: DMEK and DSAEK have a similar complication profile. However, the superiority in the visual outcome and patient satisfaction makes DMEK the preferred option for most patients.

Dependency of endothelial cell loss on anterior chamber depth within first 4 years after implantation of iris-supported phakic intraocular lenses to treat high myopia

Purpose To evaluate the effect of the anterior chamber depth (ACD) on the central corneal endothelial cell density (ECD) in eyes after implantation of an iris‐fixated phakic intraocular lens (pIOL). Setting Department of Ophthalmology, Goethe‐University, Frankfurt, Germany. Design Retrospective nonrandomized case series. Methods An Artisan pIOL was implanted in eyes of highly myopic patients. Follow‐up examinations at 1, 12, 24, 36, and 48 months included evaluation of ECD and adverse events. Three cohorts based on the ACD were established and their ECDs compared. All eyes had 1‐year and 4‐year postoperative ECD measurements available. Statistical analysis included linear regression analysis to evaluate the influence of ACD on ECD. Results The study comprised 95 eyes (52 patients). Four years after surgery the mean spherical equivalent changed from −11.06 diopters (D) ± 4.77 (SD) to −0.42 ± 0.47 D. Severe adverse events were not detected. There was a significantly higher ECD loss after 4 years in patients with an ACD of less than 3.00 mm than in those with an ACD greater than 3.40 mm (−224 cells/mm2) (P < .01). There was no significant difference in ECD between eyes with an ACD of 3.00 to 3.39 mm and eyes with an ACD less than 3.00 mm (P = .23) or more than 3.40 mm (P = .08). Conclusions The iris‐claw pIOL precisely and safely corrected high myopia. However, the loss in ECD can be considerable. Establishing stricter exclusion criteria for ACD might reduce this loss. Financial Disclosure Proprietary or commercial disclosures are listed after the references.

Short-term complications of femtosecond laser–assisted laser in situ keratomileusis cuts: Review of 1210 consecutive cases

Purpose To evaluate short‐term complications after femtosecond laser cuts for laser in situ keratomileusis (LASIK). Setting Department of Ophthalmology, Goethe University, Frankfurt, Germany. Design Retrospective consecutive case series. Methods Consecutive femtosecond laser cuts (1210 cuts in 624 patients) from LASIK performed with the Intralase FS60 between 2006 and 2014 were analyzed. The analysis looked at intraoperative and postoperative complications at 1 day, 1 week, and 1 month and factors with potential impact on the complication rate, such as ablation depth. Results No irregular, incomplete, or thin flaps, buttonholes, gas breakthrough, or free caps were observed. Intraoperatively, incomplete side cuts were observed in 4 cases (0.3%). Three of the 4 occurred during the first year of femtosecond laser usage and were explained by a software problem. Epithelial defects, limbal bleeding, and decentered flaps without negative impact on outcome were observed in 45 (3.7%), 12 (1.0%), and 5 (0.4%) eyes, respectively, on the treatment date. Diffuse lamellar keratitis (DLK) stage 1 was observed in 69 (5.7%), 36 (3.0%), and 3 (0.2%) eyes at 1 day, 1 week, and 1 month, respectively, and DLK stage 2 in 20 (1.7%), 6 (0.5%), and 2 (0.2%) eyes, respectively. An increase in total ablation depth resulted in a higher incidence of microstriae (P < .01 at 1 day, 1 week, and 1 month). An increase in the optical zone resulted in a significantly higher incidence of epithelial ingrowth at 1 day and 1 week (P < .01). Conclusion No major cut‐related complications were observed. The femtosecond laser is a safe option to create a flap in LASIK. Financial Disclosure Proprietary or commercial disclosures are listed after the references.

Effects of Atopic Syndrome on Keratoconus.

Purpose: To evaluate the effects of atopic syndrome on manifestations of keratoconus. Methods: In this retrospective study, we reviewed patient files and data generated by Scheimpflug imaging of 670 eyes of 434 keratoconus patients. Patients were divided into a study group consisting of patients suffering from atopic syndrome (110 eyes of 75 patients), namely allergic asthma, atopic dermatitis, and/or allergic rhinitis, and a control group of patients without known atopic syndrome (560 eyes of 359 patients). Results: We found a significant difference with the mean age being 36.1 ± 11.7 for the control group, 32.8 ± 9.6 for the atopic group (P = 0.002) with 1 atopic trait, and 30.4 ± 7.5 for patients with 2 or more atopic traits (P = 0.002). No statistically significant differences were found in the mean corrected distance visual acuity, corneal pachymetry, minimum relative pachymetric progression (RPImin), mean refraction, keratoconus index, anterior chamber depth and volume, Kmax, and location of Kmax in relation to the corneal apex. However, we found a significantly higher corneal density for the anterior 120 &mgr;m of the cornea in the atopic group (control: 20.74 ± 4.68, atopic group: 21.92 ± 4.65 P = 0.016). Conclusions: Keratoconus patients suffering from atopic syndrome were significantly younger but showed no topographical changes except in corneal densitometry compared with keratoconus patients without an atopic disease. This suggests atopic syndrome is a factor, which can trigger earlier manifestation of keratoconus.

Early Tomographic Changes in the Eyes of Patients With Keratoconus

PURPOSE To identify tomographic variables best suited for detecting keratoconus before manifestation of ectatic changes and showing disease progression in the early stage. METHODS Twenty-seven patients with diagnosed unilateral keratoconus were followed up for their fellow eye, which had not yet shown any ectatic changes, to determine initial change indicators toward keratoconus disease. Variables were compared to 50 normal eyes without any known disease. A following receiver operating characteristic (ROC) analysis was performed to reveal the variables best used to discriminate healthy eyes from early ectatic eyes. RESULTS The calculated mean difference of the cylinder for total corneal refractive power was only 0.07 ± 0.32 diopters (D) (anterior astigmatism = 0.12 ± 0.28 D and posterior astigmatism = 0.02 ± 0.10 D). ROC revealed the index of height decentration with an area under the curve of 0.788 ± 0.054 as the most suitable to differentiate between eyes of healthy patients and the non-ectatic eye of patients with asymmetrical keratoconus, followed by the index of vertical asymmetry of 0.772 ± 0.057 and a keratoconus index of 0.743 ± 0.062. However, with progression of the eyes into early ectactic stages, the ROC showed the highest area under the curve for D-index (0.876 ± 0.039), followed by index of height decentration (0.855 ± 0.046) and index of vertical asymmetry (0.842 ± 0.046). CONCLUSIONS Early stages of keratoconus are hard to diagnose and best results can be achieved by using index of height decentration and index of vertical asymmetry. As the disease progresses, D-index is better suited to diagnose an ectasia. Astigmatism, keratometry, and pachymetry barely change in the early stages, so these values are not as fitting as corneal elevation parameters for early diagnosis. [J Refract Surg. 2018;34(4):254-259.].

Comparison of standard and accelerated corneal cross-linking for the treatment of keratoconus: a meta-analysis

To compare results between standard and accelerated corneal collagen cross‐linking (CXL) for the treatment of progressive keratoconus.

Impact of lens densitometry on phacoemulsification parameters and usage of ultrasound energy in femtosecond laser-assisted lens surgery

OBJECTIVE The aim of this study was to find the correlation between lens densitometry measurements using Pentacam Scheimpflug imaging system with equivalent average ultrasound power and cumulative dissipated energy (CDE) in femtosecond laser-assisted lens surgery (FLALS). METHODS One hundred and twenty-four eyes were analyzed retrospectively, of which 109 had undergone cataract surgery and 15 had received refractive lens exchange with FLALS. Using the Pentacam Nucleus Staging (PNS) lens densitometry program, preoperative mean lens density and cataract grading score were evaluated. Average ultrasound power and CDE were recorded during surgery and correlated with the PNS grading and average lens density value. Exclusion criteria included small pupil size, previous ocular surgeries, tumors, optic atrophy, corneal scarring, intraoperative capsular rupture, and zonular dehiscence. RESULTS Preoperative average lens density compared with CDE showed a weak significant positive linear correlation (p < 0.0001). CDE increased as lens density increased. This was also noticed when CDE and ultrasound time were compared with the PNS grading, demonstrating a significant moderate correlation (p < 0.0001). With increasing average lens density, the equivalent average ultrasound power showed a positive correlation (p < 0.0001). A weak positive correlation between estimated fluid use and PNS was also observed (p < 0.0001). Forty-one cases that did not require ultrasound energy during phacoemulsification had a PNS score between 0 and 1. CONCLUSIONS The Centurion Phacoemulsification machine has been shown to correlate positively with the Pentacam Scheimpflug System offering an objective and repeatable measure of lens density and cataract grading. This can aid in intraoperative phacodynamics and help reduce phacoemulsification complications, such as corneal endothelial injury.