Refractive Surgery: An Interactive Case-Based Approach presents all of the necessary refractive surgery material to make an informed decision regarding diagnosis and management plans. Rather than utilizing the standard organization of most books, where major points are first introduced and then explained through a series of writings and references, this book relies on the clinical decision-making process involved with treating refractive surgery patients. Refractive Surgery: An Interactive Case-Based Approach by Dr. J. Bradley Randleman builds upon foundational initial chapters through the case presentations and focused case discussions, encompassing the major topics in refractive surgery today. For each case, the critical question is simply, “what data in this chart is the most critical to consider when evaluating this patient for surgery?” Refractive Surgery: An Interactive Case-Based Approach is unique in its format. Specifically, the book facilitates active learning by forcing the reader to think through a series of questions surrounding each patient scenario. This active learning not only facilitates better recall of the information presented but also mimics the actual physician-to-patient clinical experience, making this book more relevant than other routine refractive surgery books. Bonus! This dynamic learning tool is also supplemented by interactive online video material to further the learning experience. Enhance the clinical decision-making process by watching the videos and then answering a series of questions that lead to the conclusion of each scenario. By challenging the reader to perform the thinking and decision making up-front, and then providing some guidance on the most salient concepts for each case scenario presented along with resources to gain a deeper understanding of the most complex concepts, Refractive Surgery: An Interactive Case-Based Approach engages more in the learning process and thereby allowing to absorb and retain significantly more information to apply to patient care and the education of others. Ophthalmologists, residents, fellows, resident and fellowship educators, who want to update their refractive surgery knowledge base will appreciate the unique format and style of Refractive Surgery: An Interactive Case-Based Approach.
-Cataract surgery is the most frequently performed surgical intervention worldwide, and the number of refractive surgery procedures, such as LASIK, is growing rapidly -All editors are internationally known experts in the field -Well structured text and design, quick and easy to read -Bridges the gap between primary literature and daily practice, indispensable for continuous education and advanced training -Every 2nd year each volume is updated to include timely information about new developments
This illustrated guide is written by international opinion leaders with extensive experience in the practice of refractive surgery. It is the first book devoted to refractive complications (with practical hints and case reports on outcomes) to provide ophthalmic surgeons with the most adequate solutions for the most frequent problems. All complications are described and lavishly illustrated. The book provides ophthalmic surgeons with the most adequate solutions for the most frequent problems they face in their daily practice.
While lecturing in recent months at a number of prominent institutions, I asked some of the residents and fellows whether and how they might benefit from a book on corneal biomechanics. The typical response was the look of a deer caught in the headlights as they tried to intuit the “appropriate” answer, but had little understanding or insight as to why this would be an important and useful knowledge base for them now, or in the future. I then posed the question differently. “Would a book that explained corneal biomechanical principles and testing devices and their application in detecting eyes at risk for developing keratoconus and post-LASIK ectasia, understanding the biomechanical impact of specific types of keratorefractive surgery and riboflavin UV-A corneal collagen cross-linking, and the impact of corneal biomechanics on the fidelity of intraocular pressure measurement and risk for glaucoma progression be of interest?” Framed in this context, the answer I got was a resounding, “Yes!” Therein lies a fundamental disconnect that highlights both the opportunity and need to educate all ophthalmologists about this nascent field. This comprehensive book is strengthened by the breadth of contributions from leading experts around the world and provides an important resource for ophthalmologists at all levels of training and experience. It gives a panoramic snapshot of our understanding of corneal biomechanics today, bridging the gap between theoretical principles, testing devices that are commercially available and in development as well as current and potential future clinical applications. While there has been a long-held appreciation that all types of keratorefractive surgery have an impact and interdependence on corneal biomechanics and wound healing, the initial finite element analyses that were applied to understand radial keratotomy were limited by incorrect assumptions that the cornea was a linear, elastic, homogenous, isotropic material.1 With the advent of excimer laser vision correction, critical observations indicated that Munnerlyn’s theoretic ablation profiles did not account for either lower or higher order (e.g. spherical aberration) refractive outcomes,2 suggesting that there were important components missing from the equation—e.g., corneal biomechanics and wound healing. In a seminal editorial, Roberts3 pointed out that the cornea is not a piece of plastic, but rather a material with viscoelastic qualities. Since that time, much has been learned about spatial and depth- related patterns of collagen orientation and interweaving, as well as the biomechanical response to different keratorefractive surgeries that sever tension-bearing lamellae, as the cornea responds to and redistributes stress induced by IOP, hydration, eye rubbing, blinking and extraocular muscle forces.3-6 The first reports of post-LASIK ectasia7 highlighted the need to identify a biomechanical signature of early keratoconus as well as corneas at high risk of developing ectasia irrespective of their current topography or tomography. The introduction of two instruments into clinical use—the Ocular Response Analyzer (ORA) and the Corneal Visualization Scheimpflug Technology (Corvis ST)—that allow measurement of various biomechanical metrics further catapulted the field. The availability of these instruments in routine clinical settings allowed the systematic study of the effect of age, collagen disorders, collagen cross-linking, corneal rings, flaps of various depths, contour, sidecut angulation, pockets, and flockets, just to name of few. Future application of biomechanics to the sclera may improve our understanding of the development and prevention of myopia, as well as scleral surgeries and treatments under development for presbyopia. It was appreciated by Goldmann and Schmidt that corneal thickness and curvature would influence the measurement of applanation tonometry. The recent ability to measure some corneal biomechanical metrics have led to IOP measurement that may be more immune both to their influence and the impact of central corneal thickness (CCT). Certain chapters in this book explain how a thin cornea could be stiffer than a thick one and that stiffness is also impacted by IOP, thereby precluding simplistic attempts to adjust IOP measurements using nomograms based upon CCT alone. Also highlighted is how corneal hysteresis, the ability of the cornea to absorb and dissipate energy during the bidirectional applanation response to a linear Gaussian air puff, appears to be an independent risk factor for glaucoma progression and rate of progression.9,10 This comprehensive book starts out with a section devoted to outlining basic biomechanical principles and theories, teaching us the language of what Dupps11 has referred to as “mechanospeak”, thus providing a context and common vocabulary to better comprehend the following chapters. By first defining basic concepts such as stress-strain relationships and creep, this theoretical basis is later applied to explain the pathogenesis of corneal diseases, e.g., explaining how a focal abnormality in corneal biomechanical properties precipitates a cycle of decompensation and localized thinning and steepening, clinically expressed as ectasia progression. These early chapters further detail biomechanical differences between in-vivo and ex-vivo testing, between human and animal corneas and sclera, and between methods of testing. The second section provides a thorough description of two FDA-approved devices to measure corneal biomechanics in the clinic (i.e., the ORA and the Corvis ST), as well as an overview of potential future technologies, including OCT with air puff stimulus, ocular pulse elastography, and Brilloiun microscopy. The third and final section of the book is a thorough treatise on how to interpret the metrics derived from the waveform provided by available clinical devices; their adjunct use in ectasia risk screening; the comparative biomechanical impact of various keratorefractive surgeries and corneal procedures such as PRK, LASIK, SMILE, and corneal collagen cross-linking; the impact of corneal biomechanics on IOP measurement; and potential biomechanical markers of enhanced susceptibility to glaucoma progression. This compendium of our current knowledge of corneal biomechanics, its measurement and application, provides a strong foundation to more fully understand advances in keratorefractive and corneal surgery, diseases, and treatments, all of which are interdependent on and influence inherent corneal biomechanical properties and behavior. Both the robust aspects and limitations of our current understanding are presented, including the challenge of creating accurate and predictive finite element models that incorporate the impact of IOP, corneal thickness, geometry, and scleral properties on corneal biomechanics. This book provides a key allowing clinical ophthalmologists and researchers to grasp the basics and nuances of this exciting field and to shape it as it evolves in the future.
Drs. Gimbel and Penno provide a comprehensive look at a wide variety of refractive surgery techniques in their new book. Specific techniques are discussed along with preoperative assessments, counseling, and informed consent. In addition to chapters on the commonly performed techniques of LASIK and PRK, there are chapters on intracorneal ring segments, phakic IOL implants, refractive lensectomy, and retreatments. The authors take a practical and concise approach to a wide scope of modern refractive surgery techniques which makes this reference valuable for both the experienced and beginning surgeon. Patient examples are featured illustrating the fundamental principles of assessment and choosing the appropriate refractive surgery technique for an individual patient. The inclusion of co-management principles emphasizes integrated care during the assessment and preoperative work-up, as well as during the postoperative period. This book is an important source that covers many refractive surgery approaches to help you choose the best procedure for your patients and achieve the best results possible.
Good vision is more than 20/20 on a Snellen visual acuity chart. The modern ophthalmologist understands that contrast sensitivity, near and distance vision, performance under light and dark conditions, and the brain's interpretation of input from the sensory apparatus, are all important elements in patients' quality of vision. In Quality of Vision: Essential Optics for the Ophthalmic Surgeon, ophthalmologist and optics expert Dr. Jack T. Holladay explores the elements of vision that lie beyond Snellen testing. He explains the Quality of Vision addresses: - Measuring and treating astigmatism in corneal and IOL surgery - The importance of correcting spherical aberration in cataract and refractive surgery - IOL calculations after refractive surgery - Promising approaches to the correction of presbyopia - Other practical topics the clinician can use every day Recognized as the leader in ophthalmic optics, Dr. Holladay incorporates practical aspects of daily practice into each chapter as he expertly explains the scientific principles, mathematical formulas, and theories behind these important issues. Additionally, Quality of Vision includes numerous color illustrations to provide visual representations of the text's key points. Dr. Holladay discusses what's on everyone's mind: - How to take the best measurements and perform the best calculations to ensure good outcomes in cataract and refractive surgery - How neural adaptation can improve outcomes - How today's excimer laser systems deliver excellent optical correction, and why tomorrow's systems will perform even better Quality of Vision: Essential Optics for the Ophthalmic Surgeon is the most complete and practical reference for ophthalmologists looking to increase their understanding of optical physics and their ability to deliver good vision to their patients after cataract and refractive surgery.
Taking an engineering, rather than a mathematical, approach, Bounding uncertainty in Civil Engineering - Theoretical Background deals with the mathematical theories that use convex sets of probability distributions to describe the input data and/or the final response of systems. The particular point of view of the authors is centered on the applications to civil engineering problems, and the theory of random sets has been adopted as a basic and relatively simple model. However, the authors have tried to elucidate its connections to the more general theory of imprecise probabilities, Choquet capacities, fuzzy sets, p-boxes, convex sets of parametric probability distributions, and approximate reasoning both in one dimension and in several dimensions with associated joint spaces. If choosing the theory of random sets may lead to some loss of generality, it has, on the other hand, allowed for a self-contained selection of the topics and a more unified presentation of the theoretical contents and algorithms. With over 80 examples worked out step by step, the book should assist newcomers to the subject (who may otherwise find it difficult to navigate a vast and dispersed literature) in applying the techniques described to their own specific problems.
In this book an international panel of authors offer a clear, step-by-step approach to Small Incision Lenticule Extraction (SMILE), a new refractive procedure approved for the treatment of myopia and astigmatism that is a truly minimally invasive key-hole type surgery. The book opens by discussing important fundamentals of the technology, followed by a close look at the healing response. The current surgical techniques are then described in detail with the aim of providing easy-to-understand guidance for all who wish to perform SMILE surgery or to identify solutions to pitfalls that may arise during the learning curve. Further sections cover the clinical science relating to SMILE (explaining underlying principles), discuss ongoing investigations to further expand the spectrum of SMILE surgery and offer suggestions on how to market the procedure and communicate it to the prospective patient. This guide is “a must” for everyone who wishes to enter the exciting world of SMILE.
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
