Comparison and Evaluation of Ocular Biometry Using a New Noncontact Optical Low-Coherence Reflectometer

Rohrer, Kaspar; Frueh, Béatrice E.; Wälti, R.; Clemetson, I.; Tappeiner, Christoph; Goldblum, David

doi:10.1016/j.ophtha.2009.04.019

“…Our results reinforce earlier studies [10][11][12][13][14] reporting the strong agreement found between LENSTAR and IOLMaster in AL, average K, and IOL power. An exception is a recent study, 27 which reported less satisfactory average K agreement between IOLMaster and LENSTAR; the mean difference being 0.67 D, with 95% LoA given by (0.07, 1.20).…”

Section: Discussionsupporting

confidence: 92%

“…9 Assessing method agreement can also be useful for evaluating the relative importance of instrument variation as a source of error for IOL power. Several studies [10][11][12][13][14] that look at LENSTAR-IOLMaster agreement in AL, anterior chamber depth (ACD), IOL power, K1, and K2 measurements of phakic eyes have been done. All suggest that measurements obtained from LENSTAR and IOLMaster strongly agree.…”

Section: Introductionmentioning

confidence: 99%

Agreement analysis of LENSTAR with other techniques of biometry

Jasvinder

¹

,

Khang

²

,

Sarinder

³

et al. 2011

Eye

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Purpose To assess the agreement of the optical low-coherence reflectometry (OLCR) device LENSTAR LS900 with partial coherence interferometry (PCI) device IOLMaster and applanation and immersion ultrasound biometry. Methods We conducted the study at the Ophthalmology Clinic, University of Malaya Medical Center, Malaysia. Phakic eyes of 76 consecutive cataract patients were measured using four different methods: IOLMaster, LENSTAR and A-scan applanation and immersion ultrasound biometry. We assessed the method agreement in the LENSTARIOLMaster, LENSTAR-applanation, and LENSTAR-immersion comparisons for axial length (AL) and intraocular lens (IOL) power using Bland-Altman plots. For average K, we compared LENSTAR with IOLMaster and the TOPCON KR-8100 autorefractor-keratometer. SRK/T formula was used to compute IOL power, with emmetropia as the target refractive outcome. Results For all the variables studied, LENSTAR agreement with IOLMaster is strongest, followed by those with immersion and applanation. For the LENSTARIOLMaster comparison, the estimated proportion of differences falling within 0.33 mm from zero AL and within 1D from zero IOL power is 100%. The estimated proportion of differences falling within 0.5 D from zero average K is almost 100% in the LENSTAR-IOLMaster comparison but 88% in the LENSTAR-TOPCON comparison. The proportion of differences falling within 0.10 mm (AL) and within 1D (IOL power) in the LENSTAR-IOLMaster comparison has practically significant discrepancy with that of LENSTAR-applanation and LENSTARimmersion comparisons.Conclusions In phakic eyes of cataract patients, measurements of AL, average K, and IOL power calculated using the SRK/T formula from LENSTAR are biometrically equivalent to those from IOLMaster, but not with those from applanation and immersion ultrasound biometry.

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“…With regard to average keratometric data, it seems that the Lenstar is biometrically equivalent to the IOLMaster, 8 and the correlation between the cylinder axis measurements of the IOLMaster and the Lenstar is high. 9 However, Rohrer et al 9 observed that the differences between the axis value of the flattest meridian in the Lenstar and the IOLMaster in a large percentage of patients is unacceptably high. Besides these controversial Novel Image-Guided System/Nemeth et al results, these two devices are now the biometric standard in keratometry and, of course, in planning the diopter of the IOLs for cataract surgery.…”

Section: O R I G I N a L A R T I C L Ementioning

confidence: 99%

“…5 The Lenstar keratometry has repeatable values, 6,7 but according to Zhao et al, 7 the Lenstar and the IOLMaster cannot be used interchangeably in relation to keratometric data. With regard to average keratometric data, it seems that the Lenstar is biometrically equivalent to the IOLMaster, 8 and the correlation between the cylinder axis measurements of the IOLMaster and the Lenstar is high.9 However, Rohrer et al 9 observed that the differences between the axis value of the flattest meridian in the Lenstar and the IOLMaster in a large percentage of patients is unacceptably high. Besides these controversial…”

mentioning

confidence: 99%

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Repeatability Data and Agreement of Keratometry With the VERION System Compared to the IOLMaster

Németh¹,

Szalai²,

Hassan³

et al. 2015

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he exact measurement of the radius of the curvature of the cornea is crucial for planning the diopter of the intraocular lenses (IOLs) for implantation during cataract surgery. The error in measurements of the keratometric data can lead to unwanted postoperative refractive error. Although keratometric mistakes are not the first or most frequent source of error in today's biometric methods, 1 keratometry has an undisputed and important role in cataract surgery. Moreover, cases of implantation of toric IOLs require more precise keratometric readings and cylinder axis determination than ever before.There are numerous papers showing that the repeatability of keratometric measurements is excellent in the case of the IOLMaster (Carl Zeiss Meditec, Jena, Germany), 2-4 although above 42.0 diopters (D), the cylinder axis has relatively low repeatability data.2 In the case of the Lenstar (Haag-Streit, Koeniz, Switzerland), the interclass coefficient of the variation of the astigmatism axis was 0.915 and the mean arithmetic difference between the two measurement sessions was 3.19°, with an absolute difference of a median of 9°. 5 The Lenstar keratometry has repeatable values, 6,7 but according to Zhao et al., 7 the Lenstar and the IOLMaster cannot be used interchangeably in relation to keratometric data. With regard to average keratometric data, it seems that the Lenstar is biometrically equivalent to the IOLMaster, 8 and the correlation between the cylinder axis measurements of the IOLMaster and the Lenstar is high.9 However, Rohrer et al. 9 observed that the differences between the axis value of the flattest meridian in the Lenstar and the IOLMaster in a large percentage of patients is unacceptably high. Besides these controversialTo analyze the repeatability of keratometric and white-to-white (WTW) distance measurements with the VERION Measurement Module (Alcon Laboratories, Inc., Fort Worth, TX) and to compare the measured data to the results of the IOLMaster (Carl Zeiss Meditec, Jena, Germany). METHODS:Three images were captured with the VERION and the flattest and steepest keratometric data, the astigmatism axis, and the WTW distance were recorded. Subsequently, the axial length, the keratometric data with axis, and the WTW distance were measured with an IOLMaster. The repeatability data of the keratometric value of the VERION System, converted to cross cylinder J 0 and J 45 vector components, were analyzed. The agreement data for keratometry obtained by the VERION System and the differences regarding keratometric data and WTW distance compared to IOLMaster were calculated. RESULTS:The measurements were conducted in 50 eyes of 50 healthy volunteers (median age: 50.32 years, range: 19.34 to 85.3 years). The flattest and the steepest keratometric data, the diopter of astigmatism, the J 0 and J 45 vector components, and WTW distance did not differ significantly between devices (P > .05). Intraclass correlation coefficients (range: 0.863 to 0.994) and Cronbach's alpha values (range: 0.950 to 0.998) were high for all p...

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Instruments in Biotechnology and Medicine

Voss¹,

Feller²,

Beckmann³

2012

Handbook of Biophotonics

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The sections in this article are Photonic Instruments in Medicine Introduction Optical Window of Cells and Tissues Laser Light–Matter Interaction as a Function of Intensity Photochemical Treatment of Tissues Thermal Processes in Light–Matter Interaction Nonlinear Processes in Light–Matter Interaction (Not to Be Confused with Nonlinear Optics) Minimally Invasive Diagnostics – Endoscopy History Types and Components of Endoscopes Advantages and Disadvantages of Endoscopy Application Fields Combination of Standard White Light Endoscopic with Other Diagnostic Methods Some Trends in Endoscopy Noninvasive Diagnostics – Photoplethysmography Introduction Characterization of the PPG Signal Signal Acquisition Clinical Applications Summary Noninvasive Diagnostics – Ophthalmology Introduction Corneal Topography Perimetry Optical Biometry Retinal Imaging and Glaucoma Diagnostics Fluorescein Angiography Wavefront Analysis In Vitro Diagnostics – Microscopy Light Microscope Fluorescence Microscope New Fluorescence Microscope Techniques Confocal Microscopy Raman Microscopy In Vitro Diagnostics – Digital Slides and Virtual Microscopy In Vitro Diagnostics – Optical Methods in Clinical Analysis System Optical Spectroscopy of Blood and Urine Components Optical Spectroscopy of Tissues and Vessels Optical Spectroscopy of Agglutination and Precipitation – Nephelometry, Turbidimetry In Vitro Diagnostics – Blood Gas Pressure Measurements Optical Detection of p O 2 in Blood Optical Detection of p CO 2 in Blood Optical Detection of Further Monitoring Parameters in Intensive Care (Temperature, p H ) In Vitro Diagnostics – Photoacoustic Spectroscopy Therapy Introduction Laser Therapy in Ophthalmology – LASIK (Refraction Correction by Cornea Treatment) Photonic Instruments in Biotechnology Introduction Selected Analytical Methods Introduction Reflectometric Interference Spectroscopy ( RIf S ) Surface Plasmon Resonance ( SPR ) Fluorescence Methods Advanced Microscopic Techniques (Selection) Enzyme‐Linked Immunosorbent Assay ( ELISA ) Optical Biosensors, Biochips, Miniaturized Analytical Systems High‐Throughput Screening ( HTS ) Sample Preparation: Flow Injection Analysis Fermentation as a Central Process of Biotechnology General Aspects Fermentation Control Photobioreactors Optical Trap/Optical Tweezers Basic Scheme of Laser Tweezers and Micromanipulation Applications of Optical Tweezers

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Comparison and Evaluation of Ocular Biometry Using a New Noncontact Optical Low-Coherence Reflectometer

Cited by 135 publications

References 20 publications

Agreement analysis of LENSTAR with other techniques of biometry

Agreement analysis of LENSTAR with other techniques of biometry

Repeatability Data and Agreement of Keratometry With the VERION System Compared to the IOLMaster

Instruments in Biotechnology and Medicine

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