China
Africa
Explore chapters and articles related to this topic
Corneal Disorders
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Darren S. J. Ting, Rashmi Deshmukh, Daniel S. W. Ting, Marcus Ang
Keratoconus is the most common corneal ectactic disorder, with an estimated prevalence of 13.3–265 per 100,000 population.135 Traditionally, depending on the severity of the disease, keratoconus is managed with glasses, CL, intracorneal ring segments (ICRS), and corneal transplantation, if all measures fail.136 However, the innovation of corneal collagen cross-linking (CXL) in 2003 has revolutionized the management of keratoconus as it could halt the disease progression.137 That said, treatment success relies on early detection of the disease as CXL does not reverse the progression of keratoconus.138
Management of Fungal Keratitis
Published in Mahendra Rai, Marcelo Luís Occhiutto, Mycotic Keratitis, 2019
Mohammad Soleimani, Nader Mohammadi
Corneal collagen crosslinking (CXL) has been used to halt the progression of keratoconus by strengthening the chemical bonds between collagen bundles in the corneal stroma. Recent studies have focused on the role of CXL in the treatment of infectious keratitis. The term photoactivated chromophore for infectious keratitis (PACK)-CXL was coined in 2013 to differentiate this technique from CXL used to treat corneal ectasia. Studies showed that CXL might have a direct antifungal effect and it might slow down the melting of the cornea, delaying the need for emergency keratoplasty (Sauer et al. 2010, Hersh et al. 2011, Li et al. 2013, Saglk et al. 2013, Said et al. 2014). Still, results of studies assessing the role of PACK-CXL in the management of fungal keratitis have been questionable. Three study found hopeful outcomes on the use of PACK-CXL in fungal keratitis, nonetheless in the other study, researchers demonstrated that PACK-CXL as adjuvant therapy has no additional benefit in the treatment of moderate fungal keratitis. Additionally, in a randomized controlled trial study, assessing the efficacy of PACK-CXL in the management of recalcitrant deep fungal keratitis had to be stopped due to a high rate of perforation in the CXL group (Iseli et al. 2008, Vajpayee et al. 2015, Uddaraju et al. 2015).
Nonlinear tissue processing in ophthalmic surgery
Published in Pablo Artal, Handbook of Visual Optics, 2017
Corneal collagen cross-linking (CXL): Ultrashort laser pulses applied to the posterior cornea or to scleral tissue may be possible using two-photon absorption. Therefore, surgeons could apply CXL to deeper areas of the eye for further beneficial effects in patients with keratoconus.
Progressive corneal ectatic disease in pregnancy
Published in Clinical and Experimental Optometry, 2021
Devanshi Jani, James McKelvie, Stuti L Misra
Clinicians agree that recognition of keratoconus progression relies on a consistent change in steepness of the anterior corneal surface, steepness of the posterior corneal surface, or the rate of pachymetric change from the periphery to the thinnest point.2 However, there is currently no universally accepted quantitative criteria for defining progression as this is specific to the technology available. This is evident by the diverse patient selection criteria used in studies of corneal collagen cross-linking.36 Development of the ABCD grading system and the Belin ABCD progression display (Pentacam ®, Oculus GmbH, Wetzlar, Germany) have been suggested to allow earlier detection of keratoconus progression and it may be useful to incorporate this method in future standardised prospective studies of pregnancy-associated ectasia.37
Predictive Factors for Corneal Scarring in Progressive Keratoconus Patients after Corneal Collagen Cross-linking
Published in Ophthalmic Epidemiology, 2021
Senay Asik Nacaroglu, Ahmet Kirgiz, Nilay Kandemir Besek, Muhittin Taskapili
Wollensak et al.1 from Germany presented corneal collagen cross-linking (CXL) on the basis of the combined usage of the photosensitizer riboflavin and UVA light in 2003. CXL has been utilized for several years as a treatment alternative for progressive keratoconus for the purpose of increasing the cornea’s biomechanical stability. Although the mentioned technique has been proven to be an effective means of halting keratoconus progression,2 it has some clinical drawbacks, which are the postoperative discomfort related to removing the corneal epithelium, the long duration of treatment, and it is being unsuitable for treating very thin keratoconus corneas (thinner than 400 microns).3 While the issue of time is resolved to some extent with accelerated CXL, which is characterized by the administration of the total dose of 5.4 J/m2 in a shorter time, permanent stromal haze, which can cause visual impairment in some patients, is one of the troublesome deficiencies. Stromal opacities after corneal CXL were reported by several clinicians.4,5 Raiskup-Wolf et al.6 stated that more advanced keratoconus patients tended to present with the above-mentioned complication at an incidence rate achieving 8.6%. Kato et al.7 also reported three patients with corneal deep stromal opacity that was formed several months following corneal cross-linking.
Repeated Corneal Cross-linking (CXL) in Keratoconus Progression After Primary Treatment: Updated Perspectives
Published in Seminars in Ophthalmology, 2021
Argyrios Tzamalis, Asterios Diafas, Riccardo Vinciguerra, Nikolaos Ziakas, George Kymionis
In recent years, ophthalmology has undoubtedly made tremendous progress in the field of diagnosis and treatment. This breakthrough is associated with the evolution of technology and the introduction of modern methods into everyday clinical practice. Corneal cross-linking (CXL) is a well-established technique for the management of keratoconus and other corneal ectasias, including pellucid marginal degeneration (PMD) and iatrogenic ectasia.1–5 CXL has also been shown that it has the potential to work for infectious keratitis, due to the antimicrobial activity of ultraviolet light and riboflavin.1,6,7 Following the initial report by Wollensak et al.2 in 2003, the safety and efficacy of the procedure have been tested by several researchers in numerous publications. Initial small case series have been followed by long-term studies, which have shown that corneal collagen cross-linking may slow the progression of keratoconus.1–5 Presently, there are published series and prospective studies with an up to 10 years follow-up as well as meta-analyses that prove the effectiveness of CXL in halting keratoconus progression with success rates reaching 100%.3–5