Customized CXL

BACKGROUND: Corneal crosslinking (CXL) is used in keratoconus to strengthen and stabilize the cornea and to prevent further progression with subsequent visual loss and the possible need for keratoplasty. Correct treatment indications is crucial in this context. Since the introduction of the initial Dresden protocol, other modified CXL protocols have been proposed to optimize treatment success. OBJECTIVE: The relevant parameters for treatment indications are explained and the clinical results of new CXL protocols are presented...

PURPOSE: To describe a new treatment algorithm aimed at optimizing refractive outcomes for patients with keratoconus and cataract. SETTING: Private practice in Sydney, Australia. DESIGN: Retrospective case series. METHODS: This procedural approach involves cataract extraction with small-aperture intraocular lens (IOL) insertion, IC-8 IOL (AcuFocus, Inc.), followed by topography-guided photorefractive keratectomy (T-PRK) with simultaneous corneal crosslinking (CXL)...

In the present study (clinical trial registration number: NCT05019768), we compared the clinical outcome of corneal cross-linking with either the standard Dresden (sCXL) or the accelerated custom-fast (aCFXL) ultraviolet A irradiation protocol using riboflavin-D-α-tocopheryl poly(ethylene glycol)-1000 succinate for progressive keratoconus. Fifty-four eyes of forty-one patients were randomized to either of the two CXL protocols and checked before treatment and at the 2-year follow-up. The sCXL group was subjected to CXL with 30 min of pre-soaking and 3 mW/cm2 UVA irradiation for 30 min...

PURPOSE: To evaluate the efficacy and safety of epithelial-island crosslinking (EI-CXL) in keratoconus with corneas thinner than 400 µm. METHODS: Twenty-six patients (30 eyes) underwent EI-CXL (preserving the epithelium over the thinnest area), using standard protocol (3 mW/cm2 for 30 min). Uncorrected and best spectacle-corrected distance visual acuity (UCDVA, BCDVA), manifest refractive spherical equivalent (SEQ), mean simulated keratometry (Kmean), maximum keratometry (Kmax), and thinnest corneal thickness (TCT) were determined preoperatively and at 1, 3, 6, and 12 months following CXL...

Purpose: To evaluate depth-resolved changes of corneal biomechanical properties in eyes with corneal ectasia after corneal crosslinking (CXL) using optical coherence elastography. Methods: In a prospective pilot series of eyes with corneal ectasia, a custom high-speed swept source optical coherence tomography system was used to image the cornea before and 3 months after CXL during a low-speed applanating deformation while monitoring applanation force. Cross-correlation was applied to track frame-by-frame two-dimensional optical coherence tomography speckle displacements, and the slope of force versus local axial displacement behavior during the deformation was used to produce a two-dimensional array of axial stiffness (k)...

BACKGROUND: to study the outcomes of topography-guided customized excimer laser subepithelial ablation combined with accelerated CXL for progressive keratoconus. METHODS: Thirty-one eyes of 30 patients with progressive keratoconus were included in this prospective study. Topography-guided excimer laser ablation without refractive correction was performed. Simultaneous accelerated collagen cross-linking with ultraviolet light of 30 mW/cm2 for 4 min was followed...

PURPOSE: The aim of this study was to report novel ray-tracing customization of surface excimer laser ablation combined with higher fluence corneal crosslinking (CXL) in the stabilization and normalization of ectasia and visual rehabilitation of progressive keratoconus. METHODS: A 28-year-old man with bilateral progressive keratoconus was treated with Athens protocol: CXL combined with photorefractive surface ablation customized by a novel artificial intelligence platform calculating lower- and higher-order aberrations based on wavefront, Scheimpflug tomography, and interferometry axial length data from a single diagnostic device...

PURPOSE: To determine the efficacy of interferometry for examining the spatial changes to the corneal biomechanical response to simulated intraocular pressure (IOP) fluctuations that occur after corneal cross-linking (CXL) applied in different topographic locations. METHODS: Displacement speckle pattern interferometry (DSPI) was used to measure the total anterior surface displacement of human and porcine corneas in response to pressure variations up to 1 mm Hg from a baseline pressure of 16...

The purpose of the study was to determine the decrease in pachymetry of very thin corneas with advanced keratoconus due to corneal compaction from the ultraviolet-A (UV-A) irradiation phase of transepithelial (epi-on) cross-linking. Twenty removed corneal buttons were obtained from patients who underwent penetrating keratoplasty for advanced keratoconus. Removed corneal buttons selected from among the post-surgical specimens for this study had intact epithelium, no scarring or surgical cautery, endothelial cell density >2500 cells/mm2 , and average pachymetry over the measured points of below 400 μm...

PURPOSE: This study examined the patterned treatment of corneal collagen cross-linking (CXL) for keratoconus to reduce the complications caused by ultraviolet (UV) irradiation. By modifying the method of UV irradiation during the cross-linking process, cross-linking with a special structure is achieved, and the cross-linking effect is analyzed and compared to that of traditional cross-linking. By constructing an animal model of keratoconus, the process and effect of corneal cross-linking can be investigated more fundamentally...

PURPOSE: The aim of this study was to assess the visual, topographic, and aberrometric outcomes of a novel tissue sparing technique, topography-guided removal of epithelium, and stroma in keratoconus (TRESK) along with accelerated collagen cross-linking (CXL), 1 month after Intacs insertion. DESIGN: Prospective interventional study. METHODS: Fourty-eight eyes (45 patients) with keratoconus underwent femto-assisted Intacs insertion. After 1 month, TRESK and CXL (9 mW/cm2 for 10 minutes) was done...

PURPOSE: To compare the changes in corneal biomechanical properties and corneal tomography between transepithelial customized corneal crosslinking (C-CXL) and epithelium-off accelerated corneal crosslinking (A-CXL) in eyes with keratoconus. METHODS: Twenty eyes in 20 consecutive patients who underwent C-CXL (C-CXL group) and 20 eyes in 20 patients who underwent A-CXL (A-CXL group) were included in this retrospective comparative study. The corneal biomechanical properties were analyzed using a Scheimpflug-based tonometer, and all corneas were examined by anterior segment optical coherence tomography (AS-OCT) before and 3 months after surgery...

PURPOSE: To compare the safety and efficacy of topography-guided customized corneal cross-linking (PiXL) with standard cross-linking (CXL) for the treatment of progressive keratoconus. METHODS: In a prospective interventional analysis, the eyes of patients with progressive keratoconus underwent standard cross-linking (homogenous 9-mm ultraviolet-A irradiation of 9 mW/cm2 delivering a total fluence of 5.4J/cm2) versus topography-guided customized cross-linking (30 mW/cm2 pulsed irradiance with a total fluence ranging from 5...

PURPOSE: To evaluate the outcomes of customized corneal crosslinking (CXL) for treatment of progressive keratoconus (KC) using a transepithelial approach with supplemental oxygen. SETTING: Siena Crosslinking Center, Siena, Italy. DESIGN: Prospective interventional case series. METHODS: Twenty-seven eyes of 24 patients (mean age 29.3 ± 7.3 years) with progressive KC underwent customized corneal CXL using a transepithelial approach with supplemental oxygen...

Purpose: Photoactivated cornea collagen cross-linking (CXL) increases corneal stiffness by initiating formation of covalent bonds between stromal proteins. Because CXL depends on diffusion to distribute the photoinitiator, a gradient of CXL efficiency with depth is expected that may affect the degree of stromal collagen organization. We used second harmonic generation (SHG) microscopy to investigate the differences in stromal collagen organization in rabbit eyes after corneal CXL in vivo as a function of depth and time after surgery...

Purpose: Pellucid marginal degeneration (PMD) is a rare disease that is often mistaken for keratoconus but can similarly be treated with corneal collagen crosslinking (CXL). We report a case followed though 6 years of progressive irregular corneal flattening and thinning in both eyes (OU) after eccentric CXL for PMD. Observation: A 46-year-old man with bilateral PMD and corrected distance visual acuity (CDVA) of 20/20 (-2.00x80) in the right eye (OD) and 20/30 (+3...

<u>Purpose</u> : Corneal collagen crosslinking (CXL) through an intact epithelium (epi-on) at high irradiance could potentially improve patient comfort, visual recovery, and clinical workflow compared to conventional epi-off CXL. However, intact epithelium limits stromal delivery of the oxygen, photosensitizer, and ultraviolet-A (UV-A) radiation needed to drive CXL. This ex vivo study evaluated three different epi-on CXL protocols compared to positive and negative controls, specifically focusing on the impact of supplemental oxygen...

PURPOSE: To compare the one-year efficacy of accelerated and standard 5.4 J/cm2 protocols of cross-linking (CXL) in the treatment of progressive keratoconus. METHODS: In this systematic review, two members of the research team searched Scopus, Pubmed, ISI, Ovid, Science Direct, and Cochrane databases independently for publications between January 2010 and December 2016. The majority of retrieved studies were not randomized clinical trials (RCT), or the second arm of the RCT was either untreated or customized CXL...

PURPOSE: To report a novel application of partial topography-guided photorefractive keratectomy combined with topographically customized, higher fluence, and variable pattern corneal cross-linking applied on the same day of the treatment of keratoconus. METHODS: A topography-guided partial photorefractive keratectomy treatment of maximum 30 µm over the thinnest cone area was applied initially followed by a 7 mm, 50 µm phototherapeutic keratectomy treatment to address epithelial removal...

Purpose: The purpose of this work was to analyze the expressions of matrix metalloproteinase 9 (MMP-9), calcyclin (S100A6), and cystatin S (CST4) in the tears of keratoconus (KC) patients. The correlations between the expressions of these proteins and the values of various ocular surface parameters were examined after accelerated corneal crosslinking (A-CXL) with pulsed ultraviolet light. Methods: This prospective, observational study enrolled patients with different grades of KC, scheduled to undergo the A-CXL procedure, as well as healthy subjects...