scanning-light-scattering-profiler-slps-based-methodology-to

Scanning Light Scattering Profiler (SLPS) Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light ...

We propose a novel common-path Fourier domain optical coherence tomography (CP-FD-OCT) method for noncontact, accurate, and objective in vitro measurement of the dioptric power of intraocular lenses (IOLs) implants. The CP-FD-OCT method principle of operation is based on simple two-dimensional scanning common-path Fourier domain optical coherence tomography. By reconstructing the anterior and posterior IOL surfaces, the radii of the two surfaces, and thus the IOL dioptric power are determined. The CP-FD-OCT design provides high accuracy of IOL surface reconstruction. The axial position detection accuracy is calibrated at 1.22 Î¼m in balanced saline solution used for simulation of in situ conditions. The lateral sampling rate is controlled by the step size of linear scanning systems. IOL samples with labeled dioptric power in the low-power (5D), mid-power (20D and 22D), and high-power (36D) ranges under in situ conditions are tested. We obtained a mean power of 4.95/20.11/22.09/36.25 D with high levels of repeatability estimated by a standard deviation of 0.10/0.18/0.2/0.58 D and a relative error of 2/0.9/0.9/1.6%, based on five measurements for each IOL respectively. The new CP-FD-OCT method provides an independent source of IOL power measurement data as well as information for evaluating other optical properties of IOLs such as refractive index, central thickness, and aberrations.

Noncontact common-path Fourier domain optical coherence tomography method for in vitro intraocular lens power measurement.

Wir schlagen eine neue gemeinsame-Pfad Fourier Dom&auml;ne optische Koh&auml;renz Tomographie (CP-FD-OCT) Methode f&uuml;r reflektorlose, genau, und Objektive in-vitro-Messung der dioptrische macht Intraokularlinsen (IOLs) Implantate. Das CP-FD-OCT Methode Funktionsprinzip basiert auf einfachen zweidimensionalen Scan gemeinsamen-Pfad Fourier Dom&auml;ne Optische Koh&auml;renztomografie. Durch die vorderen und hinteren IOL-Oberfl&auml;chen zu rekonstruieren, sind die Radien der beiden Fl&auml;chen und somit die IOL dioptrische macht bestimmt. Das CP-FD-OCT-Design bietet eine hohen Genauigkeit der IOL Oberfl&auml;chenrekonstruktion. Die axiale Position Erkennungsgenauigkeit ist bei 1,22 &mu;m in ausgeglichenen Salzl&ouml;sung zur Simulation der in-situ-Bedingungen kalibriert. Die seitlichen Sampling-Rate wird durch die Schrittgr&ouml;&szlig;e der linear scanning-Systeme gesteuert. IOL-Proben mit beschriftet dioptrische macht im Low-Power (5D), Pr&auml;zisionsleistung (20D und 22D) und High-Power (36 D) Bereiche unter in-situ-Bedingungen getestet. Wir erhielten eine mittlere Leistung von 4.95/20.11/22.09/36.25 D mit hoher Wiederholgenauigkeit durch eine Standardabweichung von 0.10/0.18/0.2/0.58 D und einen relativen Fehler von 2/0.9/0.9/1.6%, basierend auf f&uuml;nf Messungen f&uuml;r jedes IOL bzw. gesch&auml;tzt. Die neue CP-FD-OCT-Methode bietet eine unabh&auml;ngige Quelle f&uuml;r IOL macht Messdaten sowie Informationen zur Bewertung andere optischen Eigenschaftendes von IOLs wie Brechungsindex, zentrale St&auml;rke und Verirrungen.

Kontaktlose gemeinsamen-Pfad Fourier Dom&auml;ne optische Koh&auml;renz-Tomographie Methode f&uuml;r in-vitro-Intraokularlinsen Leistungsmessungen.

An alternative method for quantification of glistenings in intraocular lenses (IOLs) using an integrating sphere with an adjustable back aperture to remove ballistic photons is presented. Glistenings in soft IOLs have been known for more than a decade; however, their severity and visual impact are still under investigation. A number of studies have been made to quantitatively describe glistenings in IOLs. Quantization and precise grading of IOLs will provide needed information to evaluate the severity and visual impact of glistenings in patients. We investigated the use of a simple modification of an integrating-sphere method to eliminate ballistic photons to quantitatively measure scattered light from glistenings in IOLs. The method described in this paper provides a simple and effective way to quantitatively characterize glistenings in vitro. It may be especially useful to quantify scattering associated with low-grade glistenings where the density of the scattering centers is low. Finally, the modified integrating-sphere method may also be generally applicable to quantitatively characterize scattering from other optical media.

Quantification of glistenings in intraocular lenses using a ballistic-photon removing integrating-sphere method.

Eine alternative Methode zur Quantifizierung der Glistenings in eine einstellbare hintere Blende entfernen ballistische Photonen eine Ulbricht-Kugel mit Intraokularlinsen (IOLs) wird vorgestellt. Glistenings in weiche IOLs sind seit mehr als einem Jahrzehnt bekannt; Allerdings sind ihre schwere und visuelle Wirkung noch untersucht. Eine Reihe von Studien wurden vorgenommen, um Glistenings in IOLs quantitativ zu beschreiben. Quantisierung und pr&auml;zise Abstufung der IOLs liefern ben&ouml;tigten Informationen um den Schweregrad und die visuelle Wirkung von Glistenings bei Patienten zu evaluieren. Wir untersuchten die Verwendung einer einfachen &Auml;nderung einer Integration-Kugel-Methode zur Beseitigung von ballistischer Photonen um Streulicht von Glistenings in IOLs quantitativ zu messen. In diesem Artikel beschriebene Methode bietet eine einfache und effektive M&ouml;glichkeit, Glistenings in-vitro-quantitativ zu charakterisieren. M&ouml;glicherweise besonders n&uuml;tzlich zu quantifizieren Streuung qualitativ minderwertig Glistenings zugeordnet wo ist die Dichte der Streuung Zentren gering. Schlie&szlig;lich kann die modifizierte integrieren-Kugel-Methode auch allgemein anwendbar, Streuung von anderen optischen Medien quantitativ zu charakterisieren.

Quantifizierung der Glistenings in Intraokulare Linsen mit einer ballistischen-Photon entfernen integrieren-Kugel-Methode.

Optical power properties of lenses and materials in general can be influenced by thermal changes of the material and surrounding medium. In the case of an intraocular lens (IOL) implant, the spherical power (SP), cylinder power, (CP), astigmatism, and spherical aberration are the critical fundamental properties that can significantly impact its efficacy. Directly evaluating how changes in temperature can affect these optical properties may show the importance of considering temperature when evaluating IOL optical characteristics. In this paper, we present a quantitative study on evaluating the impact of environmental temperature changes on IOL fundamental optical properties by testing IOL samples with different materials (e.g., hydrophobic and hydrophilic) and designs (e.g., monofocal and toric) to better encompass types of IOLs in conventional use today. The results from this study demonstrate that significant changes are observed as temperatures are changed from room temperature (20°C) to slightly above body temperature (40°C). Findings indicate that evaluating optical properties at arbitrary temperatures could significantly affect the characterization of IOLs that are already near the tolerance thresholds.

Impact of environmental temperature on optical power properties of intraocular lenses.

The design and manufacture of intraocular lenses (IOLs) depend upon the identification and quantitative preclinical evaluation of key optical properties and environmental parameters. The confocal laser method (CLM) is a new technique for measuring IOL optical properties, such as dioptric power, optical quality, refractive index, and geometrical parameters. In comparison to competing systems, the CLM utilizes a fiber-optic confocal laser design that significantly improves the resolution, accuracy, and repeatability of optical measurements. Here, we investigate the impact of changing the beam diameter on the CLM platform for the evaluation of IOL dioptric powers. Due to the Gaussian intensity profile of the CLM laser beam, the changes in focal length and dioptric power associated with changes in beam diameter are well within the tolerances specified in the ISO IOL standard. These results demonstrate some of the advanced potentials of the CLM toward more effectively and quantitatively evaluating IOL optical properties.

Assessing the effect of laser beam width on quantitative evaluation of optical properties of intraocular lens implants.

There is growing interest in the use of blood components for pre-hospital resuscitation of patients with major traumatic haemorrhage. It has been speculated that early resuscitation with blood components may have benefits in terms of treating trauma-induced coagulopathy, which in turn may influence survival. The proposed systematic review will evaluate the evidence on the clinical effectiveness of pre-hospital blood components (red blood cells and/or plasma or whole blood), in both civilian and military settings, compared with other resuscitation strategies in patients with major traumatic haemorrhage.

Protocol for a systematic review of the clinical effectiveness of pre-hospital blood components compared to other resuscitative fluids in patients with major traumatic haemorrhage.

Glare, glistenings, optical defects, dysphotopsia, and poor image quality are a few of the known deficiencies of intraocular lenses (IOLs). All of these optical phenomena are related to light scatter. However, the specific direction that light scatters makes a critical difference between debilitating glare and a slightly noticeable decrease in image quality. Consequently, quantifying the magnitude and direction of scattered light is essential to appropriately evaluate the safety and efficacy of IOLs. In this study, we introduce a full-angle scanning light scattering profiler (SLSP) as a novel approach capable of quantitatively evaluating the light scattering from IOLs with a nearly 360° view. The SLSP method can simulate in situ conditions by controlling the parameters of the light source including angle of incidence. This testing strategy will provide a more effective nonclinical approach for the evaluation of IOL light scatter.

A novel full-angle scanning light scattering profiler to quantitatively evaluate forward and backward light scattering from intraocular lenses.

Administration of high ratios of plasma to packed red blood cells is a routine practice for in-hospital trauma resuscitation. Military and civilian emergency teams are increasingly carrying prehospital blood products (PHBP) for trauma resuscitation. This study systematically reviewed the clinical literature to determine the extent to which the available evidence supports this practice.

Prehospital Blood Product Resuscitation for Trauma: A Systematic Review.

To present a proof-of-concept study on the development and implementation of an innovative confocal laser method platform for precise quantitative evaluation of critical optical properties unique to toric intraocular lenses (IOLs).

Confocal laser method for quantitative evaluation of critical optical properties of toric intraocular lenses.

The authors evaluated the potential for ocular damage from optical radiation emitted by Light Emitting Diode (LED) based lamps used for general illumination. Ten LED lamps were randomly selected off the shelf from a local home improvement store. The LEDs were behind diffusers in half of these lamps, while in the other half, the LEDs were clearly visible. In addition, a battery powered LED lantern having a LED source behind a diffuser was measured. The optical radiation emissions from two common incandescent lamps were also measured to compare the relative hazards of LED and incandescent lamps. All lamp samples were evaluated in accordance with procedures specified in the American National Standards Institute/Illuminating Engineering Society of North America (ANSI/IESNA) Standard RP-27.3. For comparison purposes, the lantern and 100 W incandescent lamps were also evaluated according to ANSI RP-27.1. These measurements indicate that no lamp evaluated poses any photobiological hazard, and therefore, all lamps fall in the RP-27.3 category of Exempt Group. However, when evaluated in accordance with RP-27.1, the 100 W incandescent lamp would be classified in Risk Group 1 (low risk), while the LED lantern would be classified in Risk Group 2 (moderate risk).

Article	Year
Noncontact common-path Fourier domain optical coherence tomography method for in vitro intraocular lens power measurement. Journal of biomedical optics\| PubMed ID: 22191922	2011
Quantification of glistenings in intraocular lenses using a ballistic-photon removing integrating-sphere method. Applied optics\| PubMed ID: 22193122	2011
Impact of environmental temperature on optical power properties of intraocular lenses. Applied optics\| PubMed ID: 24514132	2014
Assessing the effect of laser beam width on quantitative evaluation of optical properties of intraocular lens implants. Journal of biomedical optics\| PubMed ID: 24817618	2014
Protocol for a systematic review of the clinical effectiveness of pre-hospital blood components compared to other resuscitative fluids in patients with major traumatic haemorrhage. Systematic reviews\| PubMed ID: 25344301	2014
A novel full-angle scanning light scattering profiler to quantitatively evaluate forward and backward light scattering from intraocular lenses. The Review of scientific instruments\| PubMed ID: 26429472	2015
Prehospital Blood Product Resuscitation for Trauma: A Systematic Review. Shock (Augusta, Ga.)\| PubMed ID: 26825635	2016
Confocal laser method for quantitative evaluation of critical optical properties of toric intraocular lenses. Journal of cataract and refractive surgery\| PubMed ID: 27063527	2016
Evaluation of the Potential Optical Radiation Hazards with Led Lamps Intended for Home Use. Health physics\| PubMed ID: 27906783	2017

Robert H. James

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