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Negative dysphotopsia

Prakhyat Roop
In existing designs of intraocular lenses (IOLs), optical outcomes are compromised even after perfectly executed surgery. The reason for this is misalignment of optical axis of the eye and its visual axis. There is a need to design an IOL which compensates for this misalignment and hence enhances the optical outcomes of cataract surgery. The present innovation attempts to fulfill this unmet need and optimizes optical outcomes of all IOLs of different optical profiles - spherical, aspheric, toric, and multifocal...
December 2017: Indian Journal of Ophthalmology
Jenny Hu, Ruti Sella, Natalie A Afshari
PURPOSE OF REVIEW: To summarize the literature on dysphotopsia, focusing on strategies for management and prevention. RECENT FINDINGS: Clinical studies and ray-tracing diagrams have improved our understanding of the risk factors for positive and negative dysphotopsiae. Well known management and prevention strategies such as piggyback IOL, reverse optic capture, Nd:YAG capsulotomy, and IOL exchange are reviewed, as well as newer strategies such as the infertemporal approach to IOL implantation, 'in-the-bag nasal optic truncation' and new IOL design implantation, and new IOL design...
October 27, 2017: Current Opinion in Ophthalmology
Michael J Simpson
The region of far peripheral vision, beyond 60 degrees of visual angle, is important to the evaluation of peripheral dark shadows (negative dysphotopsia) seen by some intraocular lens (IOL) patients. Theoretical calculations show that the limited diameter of an IOL affects ray paths at large angles, leading to a dimming of the main image for small pupils, and to peripheral illumination by light bypassing the IOL for larger pupils. These effects are rarely bothersome, and cataract surgery is highly successful, but there is a need to improve the characterization of far peripheral vision, for both pseudophakic and phakic eyes...
September 9, 2017: Vision Research
Martin Wenzel, Achim Langenbucher, Timo Eppig
Negative Dysphotopsia (ND) is a dark, sometimes rounded bar or shadow in the temporal visual field after uncomplicated cataract surgery that may lead to great patient discomfort. R. Olson called it "the number one troublesome complaint after uneventful cataract surgery". The origin of this phenomena remains uncertain and is discussed conversely in literature. We have found evidence that it may be caused by a slight difference in magnification caused by the new IOL compared to the old crystalline lens. This may lead to a minimal shift of the object space corresponding the blind spot and the larger central vessels so they become visible for a short time after surgery...
August 24, 2017: Klinische Monatsblätter Für Augenheilkunde
Ivayla I Geneva, Bonnie A Henderson
The appearance of a dark shadow in the temporal periphery, otherwise known as negative dysphotopsia, continues to be a problem for some patients after routine uncomplicated cataract surgery. Etiologies include type and design of intraocular lens (IOL), anatomical features and dimensions of the eye, pupil size, angle kappa, relationship of the optic to the anterior capsule, and the position of the optic/haptic junction of the IOL. Although the primary etiology remains controversial, it is clear that the cause is multifactorial...
July 2017: Asia-Pacific Journal of Ophthalmology
Natalia Y Makhotkina, Marjan D Nijkamp, Tos T J M Berendschot, Bart van den Borne, Rudy M M A Nuijts
PURPOSE: To evaluate the incidence of negative dysphotopsia after sequential cataract surgery. METHODS: Retrospective cohort study. The incidence of negative dysphotopsia was assessed by retrospective reviewing of medical records and interviews with patients between 2 and 4 months after sequential cataract surgery. Inclusion criteria were uncomplicated surgery, postoperative corrected distance visual acuity (CDVA) ≥20/25 Snellen and the absence of ocular comorbidity...
June 29, 2017: Acta Ophthalmologica
Jack T Holladay, Michael J Simpson
PURPOSE: To determine the cause of negative dysphotopsia using standard ray-tracing techniques and identify the primary and secondary causative factors. SETTING: Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. DESIGN: Experimental study. METHODS: Zemax ray-tracing software was used to evaluate pseudophakic and phakic eye models to show the location of retinal field images from various visual field objects...
February 2017: Journal of Cataract and Refractive Surgery
Neeti Meghnad Alapati, George J Harocopos, Arsham Sheybani
We describe in-the-bag nasal intraocular lens (IOL) optic truncation, a new technique for the treatment of negative dysphotopsia. After a plane is created between the nasal capsular bag and the IOL, micrograspers and intraocular scissors are used to amputate the nasal optic edge. The amputation is to reduce the optical impact of the IOL edge and nasal anterior capsule on the occurrence of negative dysphotopsia. The technique addresses many of the proposed mechanisms contributing to the development of negative dysphotopsia and can theoretically be used in all patients with chronic symptomatology...
December 2016: Journal of Cataract and Refractive Surgery
Natalia Y Makhotkina, Tos T J M Berendschot, Rudy M M A Nuijts
PURPOSE: To compare the extension of peripheral visual fields in phakic and pseudophakic patients and to evaluate whether Goldmann kinetic perimetry can be used as an objective measure of negative dysphotopsia. SETTING: University Eye Clinic, Maastricht University Medical Centre, Maastricht, the Netherlands. DESIGN: Prospective and case-control study. METHODS: Kinetic perimetry was performed with V4e and I4e stimuli...
November 2016: Journal of Cataract and Refractive Surgery
Garett S Frank, Preeya K Gupta
No abstract text is available yet for this article.
2016: International Ophthalmology Clinics
Henk A Weeber, Sieger T Meijer, Patricia A Piers
PURPOSE: To describe and to experimentally assess a new intraocular lens (IOL) design using new diffractive technology. SETTING: AMO Groningen b.v., Groningen, Netherlands. DESIGN: Experimental study. MATERIALS AND METHODS: The basic principles of the new diffractive technology are described. The new IOL comprises two diffractive technologies; one is designed to extend the range of vision by elongating the focus, and the other increases the retinal image contrast by correcting chromatic aberration...
December 2015: Journal of Cataract and Refractive Surgery
Michael J Simpson
At very large visual angles, vignetting can occur at the edge of an intraocular lens (IOL), because it is much smaller than the natural crystalline lens that it replaces. Ray trace calculations show that, by 80-90 deg of input visual angle, it is possible that about half the light is no longer focused by the IOL. This may create curved, peripheral, shadowlike regions, which are a clinical characteristic of negative dysphotopsia. The imaging characteristics for this "far peripheral vision" region are different from those of a phakic eye, whether or not negative dysphotopsia is experienced...
September 1, 2015: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Clare Kirwan, John M Nolan, Jim Stack, Tara C B Moore, Stephen Beatty
PURPOSE: To investigate subjectively reported outcomes following cataract surgery and the relationships between such outcomes in the context of falling thresholds for cataract surgery. SETTING: Large, private, non-refractive cataract practice, Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland METHODS: Pre-operative, intra-operative and post-operative data of 2552 eyes undergoing phacoemulsification and implantation of the Tecnis(R) ZCB00 1-piece intraocular lens (IOL) by a single surgeon between July 2009 and October 2013 was analysed...
October 2015: Graefe's Archive for Clinical and Experimental Ophthalmology
Natalia Y Makhotkina, Tos T J M Berendschot, Henny J M Beckers, Rudy M M A Nuijts
PURPOSE: Our aim was to evaluate the resolution of negative dysphotopsia after supplementary implantation of a sulcus-fixated intraocular lens (IOL). METHODS: This was a retrospective case series. Patients with severe negative dysphotopsia were treated with supplementary implantation of the Rayner Sulcoflex Aspheric (653 L) IOL. Primary outcome measurements were subjectively reported complaints of dysphotopsia, best corrected distance visual acuity (CDVA), iris-IOL distance, anterior chamber depth (ACD) and volume (ACV), angle opening distance and trabecular-iris space area at 500 and 750 μm...
June 2015: Graefe's Archive for Clinical and Experimental Ophthalmology
Michael J Simpson
Some intraocular lens (IOL) patients report seeing "dark shadows" at visual angles that are larger than 60°-70°. Raytrace models of the pseudophakic eye show that light starts to miss the IOL at large visual angles because the implant diameter of about 6 mm is much smaller than the natural crystalline lens diameter of 9.5 mm. This light forms a second displaced image on the peripheral retina. To evaluate the appearance of the image, raytrace software was used to image an illuminated window onto the highly curved retina, and a method was developed to project the image back to object space for evaluation on a flat surface...
December 1, 2014: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Christopher T Hood, Alan Sugar
PURPOSE OF REVIEW: To describe the common causes of, and management strategies for, nonrefractive subjective visual complaints after cataract surgery. RECENT FINDINGS: Over the past decade, clinical observations and ray-tracing models have greatly increased our understanding of positive and negative dysphotopsias after cataract surgery. The primary factor behind positive dysphotopsias is the use of high refractive index square-edge intraocular lenses (IOLs). Primary and secondary factors that underlie negative dysphotopsias are now better characterized, which has led to successful interventions including IOL exchange and Nd:YAG laser anterior capsulotomy...
January 2015: Current Opinion in Ophthalmology
Tomas R Burke, Larry Benjamin
PURPOSE: To determine whether intraocular lens (IOL) exchange with insertion of a sulcus-fixated IOL is an effective treatment for the management of pseudophakic negative dysphotopsia. SETTING: Department of Ophthalmology, Stoke Mandeville Hospital, Buckinghamshire, United Kingdom. DESIGN: Case series. METHODS: Participants in the study were recruited prospectively from the clinic at the time of diagnosis or retrospectively from the operating room logs by identifying all patients who had IOL exchanges over a 4-year period (2009 to 2012)...
September 2014: Journal of Cataract and Refractive Surgery
David V Folden
UNLABELLED: This report describes 6 cases in which neodymium:YAG (Nd:YAG) laser anterior capsulectomy achieved limited success in treating negative dysphotopsia. In 5 eyes with the Akreos AO MI60L posterior chamber intraocular lens (PC IOL), the dysphotopsia symptoms resolved completely (3 eyes) and partially (2 eyes) depending on the extent of the Nd:YAG laser anterior capsulectomy. In 1 eye with the Acrysof IQ toric PC IOL, the symptoms did not improve. Success with this procedure in patients with the Akreos AO MI60L PC IOL supports the role of the anterior capsule in the etiology and mechanism of negative dysphotopsia...
July 2013: Journal of Cataract and Refractive Surgery
David L Cooke, Susan Kasko, Lucas O Platt
UNLABELLED: It has been suggested that a clear anterior nasal capsule contributes to negative dysphotopsia and that symptoms may resolve with opacification of the capsule. We describe a case in which negative dysphotopsia occurred despite a translucent anterior peripheral capsule and resolved following laser removal of the anterior nasal capsule. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
July 2013: Journal of Cataract and Refractive Surgery
Jack T Holladay, Huawei Zhao, Carina R Reisin
PURPOSE: To determine the cause of negative dysphotopsia and the location, appearance, and relative intensity of such images in pseudophakic eyes. SETTING: Baylor College of Medicine, Houston, Texas, USA. DESIGN: Reporting available data addressing a specific clinical question. METHODS: Negative dysphotopsia was simulated using the Zemax optical design program. The nominal values for the pseudophakic eye model were as follows: IOL power, 20...
July 2012: Journal of Cataract and Refractive Surgery
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