Corneal Epithelial Remodeling After Standard Epithelium-off Corneal Cross-linking in Keratoconic Eyes
The corneal ectasia disorders, such as keratoconus, pellucid marginal degeneration, and postoperative corneal ectasia (keratectasia), share two main attributes: impairment of visual acuity and progressive corneal thinning and steepening that leads to asymmetric anterior and posterior corneal surfaces and irregular astigmatism.1,2 Variation in the thickness of the corneal epithelium can compensate to some extent and thereby mask underlying stromal topographic irregularities.3 For example, in eyes with mild to moderate keratoconus, the epithelium tends to be thinner over the apex of the corneal (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Jeferson Lautert, MD Source Type: research
Long-term Results of Corneal Cross-linking for Terrien's Marginal Degeneration
Terrien's marginal degeneration is a progressive bilateral peripheral corneal disorder that primarily affects the superior cornea, causing irregular astigmatism or ectasia in most cases.1,2 The typical findings include: corneal thinning and the presence of yellowish-white small stromal opacities in the superior-nasal quadrant, neovascularization, scarring, and lipid deposits at the edges of the area of thinning. Some variant forms even show prominent inflammatory signs. Terrien's marginal degeneration appears associated with pseudo-pterygium in 20% of cases, whereas it presents with (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Jos é Lamarca, MD, PhD Source Type: research
Biomechanical Properties of Human Cornea Tested by Two-Dimensional Extensiometry Ex Vivo in Fellow Eyes: Femtosecond Laser –Assisted LASIK Versus SMILE
In 2008 Sekundo et al. introduced the minimally invasive small incision lenticule extraction (SMILE), which was published in 2011.1 Unlike in femtosecond laser –assisted LASIK (FS-LASIK), SMILE does not require a flap and the lenticule is extracted via a 2- to 3-mm incision, leaving the remaining anterior stroma and Bowman's layer untouched. SMILE offers potential advantages such as more postoperative comfort and patient satisfaction,2 less postoperative discomfort due to faster corneal healing,3,4 less neurotrophic keratopathy, and a presumed better preservation of biomechanical stability.4–6 (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Bogdan Spiru, MD Source Type: research
Agreement Between Internal Astigmatism and Posterior Corneal Astigmatism in Pseudophakic Eyes
Internal astigmatism, which is the discrepancy between refractive and keratometric astigmatism, is the element of total ocular astigmatism that is not caused by the anterior corneal surface. The magnitude of internal astigmatism varies between 0.07 and 2.58 diopters (D), with a mean value of 0.79 D, in normal eyes.1 This astigmatism provides a compensatory effect for anterior corneal astigmatism, which is predominantly with-the-rule.2 The contribution of internal astigmatism to refractive astigmatism has been of interest to surgeons desiring to determine the optimal power for the toric (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Sepehr Feizi, MD, MSc Source Type: research
Re-engineering the Hong Kong Quality of Life Questionnaire to Assess Cataract Surgery Outcomes
Cataract remains the leading cause of blindness in the world and cataract surgery is the most commonly performed elective surgery worldwide, with high success rates in improving vision and quality of life.1,2 During the past few decades, we have witnessed a rapid progression in cataract surgical techniques, including a push to bilateral cataract surgery due to the prospect of rapid rehabilitation and economic benefits.3 In addition to blindness and visual impairment, cataract is associated with a high rate of falls, accidents, and depression.4 –6 Although the impact of cataract is often (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Jyoti Khadka, PhD Source Type: research
Short-term Observation of Intraocular Scattering and Bowman's Layer Microdistortions After SMILE-CCL
SMILE is a safe and efficient myopia correction method. SMILE has gained wide acceptance and developed rapidly in recent years. For example, Zhou et al.1 improved the lenticule separation and extraction procedures and developed the SMILE with continuous curvilinear lenticulerhexis (SMILE-CCL) technique. As described previously, the SMILE-CCL technique exhibits outcomes similar to or better than those of traditional SMILE. SMILE-CCL is more efficient and offers good-quality lenticule extraction and satifactory refractive outcomes.1,2 Bowman's layer microdistortions have been observed after both (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Huamao Miao, MD, PhD Source Type: research
Comments on Femtosecond Lenticule Extraction for Spherocylindrical Hyperopia Using New Profiles
We read with interest the article by Sekundo et al.1 about their early experience with femtosecond lenticule extraction (FLEx) for the correction of low to moderate hyperopia. One of the greatest challenges of hyperopic correction with LASIK continues to be the lower predictability and the higher incidence of refractive regression2 compared to myopic corrections. In fact, up to 30% of eyes treated with hyperopic LASIK require an enhancement.3,4 Although Sekundo et al. provided reasonable visual and refractive outcomes, we have some concerns about their approach to correct hyperopia. First, we (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Montserrat Garcia-Gonzalez, MD, PhD Source Type: research
Factors Associated With Residual Astigmatism After Toric Intraocular Lens Implantation Reported in an Online Toric Intraocular Lens Back-calculator
Although toric intraocular lenses (IOLs) have demonstrated considerable success in reducing astigmatism at the time of cataract surgery, residual refractive astigmatism remains in some patients. With early toric IOL calculators, aggregate results indicated that only approximately 70% of eyes implanted with a toric IOL had 0.50 diopters (D) or less of refractive astigmatism postoperatively.1 The advent of toric IOL calculators that incorporated consideration of posterior corneal astigmatism appears to have increased this number to near 80%.2,3 Although these percentages are significantly (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Richard Potvin, OD Source Type: research
Comparison of Single-Step Transepithelial Photorefractive Keratectomy With or Without Mitomycin C in Mild to Moderate Myopia
Corneal haze is a common complication of photorefractive keratectomy (PRK). Clinically insignificant haze affects almost every eye undergoing PRK, whereas clinically significant haze affects 0.3% to 3% of the treated eyes.1 Corneal haze can reduce the efficacy of the surgery by leading to fluctuations in vision, irregular astigmatism, and myopic regression.2 Mitomycin C (MMC) has been successful in preventing haze after PRK in studies of low, medium, and high myopia.3 –5 There are several studies suggesting MMC application during PRK.5–8 However, in a study of eyes with mild to moderate (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Soheil Adib-Moghaddam, MD Source Type: research
Wound Healing, Inflammation, and Corneal Ultrastructure After SMILE and Femtosecond Laser –Assisted LASIK: A Human Ex Vivo Study
Small incision lenticule extraction (SMILE) is an all-femtosecond laser technique that has recently been approved by the U.S. Food and Drug Administration for the surgical correction of myopia. It has been hypothesized that by obviating the need for excimer laser photoablation, SMILE may elicit less chemokine and cytokine release with reduced inflammatory response and wound healing reaction of the corneal stroma.1 –3 Evidence derived from rabbit models has accumulated that SMILE4,5 (and its predecessor technique femtosecond lenticule extraction [FLEx]2) induces low levels of inflammatory cell (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Nikolaus Luft, MD, PhD Source Type: research
Subjective Visual Performance and Objective Optical Quality With Intraocular Lens Glistening and Surface Light Scattering
Hydrophobic acrylic intraocular lenses (IOLs) have become prevalent since the advent of small-incision cataract surgeries, possibly due to the reduced occurrence of posterior capsule opacification and calcification compared with IOLs made of other materials.1 However, glistenings and surface light scattering have been mainly reported in association with hydrophobic acrylic IOLs, specifically AcrySof IOLs (Alcon Laboratories, Inc., Fort Worth, TX).2 Glistenings are defined as sparkling bright spots under slit-lamp examination and surface light scattering is described as pronounced dense (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - June 11, 2018 Category: Opthalmology Authors: Furong Luo, MD Source Type: research
Corneal Allogenic Intrastromal Ring Segments (CAIRS) Combined With Corneal Cross-linking for Keratoconus
Intrastromal corneal ring segments (ICRS) are small curvilinear segments made of synthetic material that are implanted deep in the corneal stroma to alter the corneal curvature.1 –7 They have an arc shortening effect and act as spacer agents to effect alteration in the corneal curvature and regularization of the corneal surface.1–5 Although introduced for the treatment of myopia, they are currently used more commonly for the treatment of corneal ectatic disorders, predom inantly keratoconus. However, being made of synthetic material, there have been reports of complication rates up to 30%, (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - May 9, 2018 Category: Opthalmology Authors: Soosan Jacob, MS, FRCS, DNB Source Type: research
Therapeutic Refractive Surgery: State of Technology and a Call to Action
Although most modern corneal refractive surgery patients achieve extraordinary visual outcomes and serious complications are rare, it is critical that we focus more attention on developing methods and technologies to help those patients who have suffered complications and currently may be thought to have limited options for their repair. This was the main driving force behind the foundation of the Therapeutic Refractive Surgery section.1 We hope that by providing a rigorous scientific forum for developing technology and reporting such cases, we can foster increased development speed of new (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - May 9, 2018 Category: Opthalmology Authors: Dan Z. Reinstein, MD, MA(Cantab), FRCSC Source Type: research
Corneal Inlays for Presbyopia Explanted Due to Corneal Haze
The KAMRA inlay (AcuFocus, Inc., Irvine, CA) was the first corneal inlay to receive approval from both the European Commission and the U.S. Food and Drug Administration. It uses the principle of small-aperture optics to improve near vision by increasing the depth of focus.1 The current version (ACI 7000 PDT) is a 5- μm thick, opaque, ring-shaped implant measuring 3.8 mm in diameter with a central 1.6-mm aperture that allows only central collinear light to reach the retina.1 The central aperture has 8,400 laser-etch perforations with a random pattern of holes, each 5 to 11 μm in diameter (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - May 9, 2018 Category: Opthalmology Authors: Hon Shing Ong, FRCOphth Source Type: research
Comparing Femtosecond Laser –Assisted Cataract Surgery Before and After Phakic Intraocular Lens Removal
Phakic intraocular lenses (IOLs) offer an evidence-based and viable approach for surgical correction of moderate to higher levels of refractive errors.1 Advantages include decent refractive predictability and refractive correction without loss of accommodation.2,3 The main reason for phakic IOL explantation is cataract formation, which is significantly accelerated after phakic IOL implantation.2 –4 Patients who were treated with phakic IOL surgery are often younger and healthier than patients who had routine cataract surgery with high demanding claims. Nonetheless, a bilentectomy including an (Source: Journal of Refractive Surgery)
Source: Journal of Refractive Surgery - May 9, 2018 Category: Opthalmology Authors: Tim Schultz, MD, FEBO Source Type: research
