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The surgical correction of astigmatism is the last frontier to optimizing visual outcomes for patients. Practical Astigmatism: Planning and Analysis is a comprehensive guide to correcting astigmatism from pre-operative planning to post-operative analysis. This provides readers with unique insight to what actually happened surgically: did the astigmatism over or under correct? Was it on-axis or off-axis? With this book, ophthalmologists will be able to analyze previous procedures with the appropriate nomograms and more often achieve targeted outcomes. Dr. Noel Alpins has developed the Alpins Method of astigmatism to provide accurate planning and analysis of astigmatism procedures. His method focuses on analyzing refractive and corneal astigmatism parameters and using the results in future surgery to improve visual outcomes. The importance of the ocular residual astigmatism (ORA) is detailed when planning astigmatism surgery. Practical Astigmatism features vector planning for refractive laser surgery as well as planning and analysis applied to cataract and limbal relaxing incisions, , in addition to demonstrating graphical analysis of astigmatism using high quality vector and fan diagrams, as used in scientific journals. In addition, hemidivisional analysis of the irregular cornea, corneal coupling in incisional and excimer laser surgery for mixed astigmatism and toric IOL planning with total corneal power using corneal topographic astigmatism (CorT total) are addressed as well. Some Questions Answered Inside: What is the difference between regular and irregular astigmatism? How do I diagnose each, and how does this affect my surgical technique? Can I incorporate corneal astigmatism when performing excimer laser surgery? Why are my LRIs undercorrecting the astigmatism? Is it safe to perform excimer laser on keratoconous patients? Which corneal astigmatism measure do I choose and what do I do following a refractive surprise? Practical Astigmatism: Planning and Analysis will help ophthalmologists, optometrists, and technicians alike address each patient's unique circumstances and act as your in-depth guide to correcting astigmatism. Testimonials... \"For more than three decades I have been listening to, arguing with, and admiring the work of Dr. Noel Alpins in the field of astigmatism. Despite his remote location on the small island of Australia, his knowledge of astigmatism is at the peak of Mt. Everest. There are few others who have devoted their careers to understanding and managing astigmatism for which the world of ophthalmology is truly grateful.\" - Robert H. Osher, MD \"Noel is an original thinker who took on and conquered the complexities of astigmatism analysis, publishing the seminal papers on the way. His work has formed the cornerstone from which our current understanding and management of astigmatism has been built. He is someone from whom we have all learnt a great deal and this book is a testament to this.\" - Dan Z Reinstein, MD MA(Cantab) FRCSC DABO FRCOphth FEBO

Since the introduction of the first toric intraocular lens (IOLs) in the early 1990s, these lenses have become the preferred choice for surgeons across the globe to correct corneal astigmatism during cataract surgery. These lenses allow patients to enjoy distortion-free distance vision with excellent outcomes. They also have their own set of challenges. Inappropriate keratometry measurement, underestimating the posterior corneal astigmatism, intraoperative IOL misalignment, postoperative rotation of these lenses, and IOL decentration after YAG-laser capsulotomy may result in residual cylindrical errors and poor uncorrected visual acuity resulting in patient dissatisfaction. This review provides a broad overview of a few important considerations, which include appropriate patient selection, precise biometry, understanding the design and science behind these lenses, knowledge of intraoperative surgical technique with emphasis on how to achieve proper alignment manually and with image-recognition devices, and successful management of postoperative complications.

Femtosecond laser technology has become widely adopted by ophthalmic surgeons. The purpose of this study is to discuss applications and advantages of femtosecond lasers over traditional manual techniques, and related unique complications in cataract surgery and corneal refractive surgical procedures, including: LASIK flap creation, intracorneal ring segment implantation, presbyopic treatments, keratoplasty, astigmatic keratotomy, and intrastromal lenticule procedures.

To compare long-term clinical outcomes following small incision lenticule extraction (SMILE) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) for myopia and myopic astigmatism correction. In this retrospective study, we enrolled a total of 101 patients (101 eyes) who underwent SMILE or FS-LASIK 3 years prior. Measured parameters included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction and corneal wavefront aberrations. No significant differences in patient characteristics were found between the two groups. At the 3-year follow-up, UDVA was better than or equal to 20/20 in 90% and 85% (p=0.540) of the eyes; the efficacy indexes were 1.05±0.19 and 1.01±0.21 in the SMILE and FS-LASIK groups, respectively (p=0.352). Safety indexes were 1.19±0.17 and 1.15±0.20 in the SMILE and FS-LASIK groups, respectively (p=0.307). Eighty per cent and 65% of eyes were within ±0.50 D of the attempted spherical equivalent correction after SMILE and FS-LASIK, respectively (p=0.164). Vector analysis revealed no significant differences in astigmatic correction between the two groups (p>0.05). Surgically induced spherical aberration was higher in the FS-LASIK group than in the SMILE group (p<0.001). Long-term follow-up analysis suggested that both SMILE and FS-LASIK were safe and equally effective for myopic and astigmatic correction.

BackgroundTo evaluate the 5-year results of Refractive Lenticule Extraction (ReLEx) as Small Incision Lenticule Extraction (SMILE) technique for treatment of myopia and myopic astigmatism.MethodsIn 2008/2009, the worldwide first 91 eyes were treated using a novel surgical technique (SMILE), where a refractive lenticule of intrastromal corneal tissue is removed though a small incision completely eliminating flap-cutting. 56 out of 91 eyes of the original treatment group volunteered for re-examination 5 years after surgery. Uncorrected distance visual acuity and corrected distance visual acuity after 5 years, objective and manifest refractions as well as evaluation of the interface and corneal surface by slit-lamp examination were documented. Late side effects like corneal scars, corneal ectasia, persistent dry eye symptoms or cataract were documented.Results5 years postoperatively, no significant change to the 6-month data was found. Spherical equivalent was −0.375 D and therefore close to target refraction (emmetropia). 32 of the 56 eyes had gained 1–2 Snellen lines. There was no loss of 2 or more lines over the 5-year period. Regression in the long term was 0.48 D.ConclusionsThis first long-term study demonstrates SMILE to be an effective, stable and safe procedure for treatment of myopia and myopic astigmatism.Clinical trial numberDE/CA93/KP/07/001. Post-results.

AimsTo describe a simple surgical technique consisting of opening the vertical graft-host junction (GHJ) to manage high astigmatism following deep anterior lamellar keratoplasty (DALK) and to report postoperative visual and topographic outcomes.MethodsThis is a retrospective interventional case series. Patients affected by high astigmatism after DALK underwent progressive opening of the previous GHJ at the steep meridians, established with preoperative topography and intraoperative keratoscopic guidance. Evaluations were carried out with best corrected visual acuity (BCVA), refractive astigmatism (RA) and keratometric astigmatism (KA) measured with Casia (Tomey, Japan). Visits were conducted preoperatively (T0), 1 week (T1), 6 months (T2) and 1 year after surgery (T3). The Alpins Method was used to evaluate vectorial changes in KA between T0 and T3.ResultsFifteen patients were included in the analysis. BCVA (median (IQR)) increased significantly from 0.70 (0.5–1.1) at T0 to 0.20 (0.1–0.3) logMAR at T3 (p=0.001). RA (mean±SD) at T3 was 2.28±1.59 dioptres (D). KA (mean±SD) varied significantly from 8.04±2.14 D at T0 versus 2.93±1.94 D at T1 versus 3.15±1.79 D at T2, versus 3.23±1.63 D at T3 (p<0.0001). Vectorial analysis showed that target induced astigmatism (mean±SD) was 8.04±2.14 D, while surgically induced astigmatism (mean±SD) was 7.89±4.27 D. Correction index (mean±SD) was 0.92±0.33.ConclusionsHigh astigmatism after DALK can be safely and effectively managed by opening the GHJ down to the cleavage plane achieved with the previous surgery, providing low KA and RA, with an overall low tendency to overcorrection.

To assess surgically induced astigmatism (SIA) after XEN gel stent implantation over 5 visits during a 3-month follow-up. Changes in intraocular pressure (IOP), IOP-lowering medications, and best-corrected visual acuity (BCVA) were also assessed. This prospective cohort study recruited 24 eyes from 24 glaucoma patients at KKU Eye Center, Khon Kaen University, Thailand. All eyes underwent XEN implantation, using our specific surgical technique. We evaluated both the magnitude and the axis of SIA at 1, 2 weeks, 1, 2 and 3 months after the procedure. Preoperative and postoperative intraocular pressure (IOP), IOP-lowering medications, and best-corrected visual acuity (BCVA) were also analyzed. We observed a statistically significant centroid SIA of 0.14 D. at an axis of 105° and median SIA of 0.36 D. at 1 week following XEN (p < 0.01). However, no further significant statistical change in SIA was found at 2 weeks, and 1, 2, and 3 months postoperatively. Additionally, there was no significant change in BCVA after XEN. Moreover, reductions in IOP and IOP-lowering medications were statistically significant. Ab Interno XEN gel stent implantation induces a small SIA immediately after the surgery, but no further significant change during 3-month follow-up period. Although SIA has no significant effect on visual acuity, this should be addressed with patients preoperatively. Further studies are needed to investigate how different surgical techniques may affect refractive changes after XEN.

To evaluate the 10-year results of refractive lenticule extraction using the small incision lenticule extraction (SMILE) technique for treatment of myopia and myopic astigmatism. In 2008-2009, the first 91 eyes were treated using a novel surgical technique (SMILE), in which a refractive lenticule of intrastromal corneal tissue is removed through a small incision, completely eliminating flap cutting. A total of 56 of 91 eyes of the original treatment group volunteered for reexamination 10 years after surgery, including uncorrected and corrected distance visual acuity, objective and manifest refraction, and evaluation of the interface and corneal surface by slit-lamp examination. Late side effects such as corneal scarring, corneal ectasia, persistent dry eye symptoms, or cataract were documented. At 10 years postoperatively, there was no significant change from the 6-month results. Spherical equivalent was -0.35 ± 0.66 diopters and therefore close to target refraction. Sixteen of the 56 eyes (29%) had gained one to two Snellen lines. There was no loss of two or more lines in the long term. Regression was -0.35 ± 0.66 diopters over the 10-year period. This 10-year long-term study demonstrates SMILE to be an effective, stable, and safe procedure for the treatment of myopia and myopic astigmatism. [J Refract Surg. 2019;35(10):618-623.].

Myopia is increasing worldwide. Although the exact etiology of myopia is unknown, outdoor activity is one of the most important environmental factors for myopia control. We previously reported that violet light (VL, 360–400 nm wavelength), which is abundant in the outdoor environment, suppressed myopia progression for individuals under 20 years of age. However, whether VL is also effective for adult high myopia, which can be sight-threatening, has remained unknown. To investigate the influence of VL for adult myopia, we retrospectively compared the myopic progression and the axial length elongation over five years in adult high myopic patients over 25 years of age after two types (non-VL transmitting and VL transmitting) of phakic intraocular lens (pIOL) implantation. We found that high myopic patients with the non-VL transmitting pIOLs implanted are almost two times more myopic in the change of refraction and four times longer in the change of axial length, compared to those implanted with the VL transmitting pIOLs. This result indicated that the VL transmitting pIOL suppressed myopia progression and axial length elongation compared with the non-VL transmitting one. In conclusion, our study showed the VL possibly has an anti-myopia effect for human adults with high myopia.

In the field of refractive surgery, precise and standardized terminology allows for effective communication and is a requisite for comparison between studies.1–3 Looking at standardized astigmatism vector analysis, the terms “surgically induced astigmatism (SIA)” and “target induced astigmatism (TIA)” represent the achieved and attempted correction.4 The difference between TIA and SIA gives the “difference vector (DV)” and corresponds to the residual astigmatism error. 1 This definition emphasizes that SIA refers specifically to the astigmatism that results from an entire surgical procedure in laser vision correction and intraocular procedures, where the SIA acts as a comparison to the TIA. [...]to enhance clarity and eliminate confusion, we propose maintaining SIA to describe the overall astigmatism resulting from an entire surgical procedure and “incision-related astigmatism” as a term to describe astigmatism induced solely by corneal incisions.