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With the advancements in ocular biometric technology, there have been significant improvements in accurately and efficiently measuring ocular parameters. The aim of this study is to compare the reliability of biometric parameters obtained using a new frequency-domain optical coherence tomography (SD-OCT) biometer with the measurements obtained from swept-source OCT (SS-OCT) and optical low coherence reflectometry (OLCR) biometers. This study employed an observational cross-sectional design. Measurements of axial length (AL), flat and steep corneal keratometry (K1 and K2), and central corneal thickness (CCT) obtained using the The Colombo IOL were compared with those obtained with the IOLMaster 700 and SW-9000 devices. The agreement were evaluated using intraclass correlation coefficient (ICC) and Bland-Altman analyses. The differences of the measurements of the three increments were assessed by one-way ANONA. 73 right eyes of 73 healthy pediatric subjects were analyzed. The AL difference measured by Colombo IOL compared with IOLmaster700 and SW-9000 were 0.00 ± 0.02 mm and - 0.07 ± 0.05 mm, respectively (P > 0.05, ANOVA). There was no statistically significant difference in CCT, K1, and K2 among the three instruments (all P > 0.05, ANOVA). The ICC values for AL, K1, K2, and CCT were 0.999, 0.996, 0.995, and 0.998, respectively. The Bland-Altman analysis showed an agreement of AL, K1, K2, and CCT with Colombo IOL and IOLMaster 700 spanned over 0.08 mm, 0.71D, 0.69D, and 12.17 μm, respectively. The agreement of AL, K1, K2, and CCT with Colombo IOL and SW-9000 spanned approximate 0.21 mm, 0.75D, 1.06D, and 14.37 μm, respectively. The new SD-OCT biometer and the SS-OCT biometer showed strong agreement in measuring AL and CCT in healthy pediatric subjects. This supports the reliability of the new SD-OCT biometer as an alternative for assessing these parameters. However, K1 and K2 could not be used interchangeably in clinical practice. Further research is needed to explore their applicability in different clinical settings and patient populations."light" />., (© 2024. The Author(s).)

Background: To analyze the difference and agreement between measurements obtained by a new fully automatic optical biometer, the SW-9000 μm Plus, based on optical low-coherence reflectometry (OLCR) and a commonly used optical biometer (Pentacam AXL) based on Scheimpflug imaging with partial coherence interferometry (PCI)., Methods: The central corneal thickness (CCT), anterior chamber depth (ACD, from epithelium to anterior lens surface), lens thickness (LT), mean keratometry (K m ), corneal astigmatism, corneal diameter (CD), pupil diameter (PD), and axial length (AL) of 74 eyes (from 74 healthy subjects) were measured using the SW-9000 μm Plus and the Pentacam AXL to determine the agreement. Double angle plots were used for astigmatism vector analysis. Bland-Altman and 95% limits of agreement (LoA) were calculated., Results: Statistically significant differences were detected for all parameters but J 0 vector. The Bland-Altman analysis of AL, CCT, ACD, K m , CD, J 0 and J 45 indicated a high level of agreement between the two devices. Among AL, CCT, ACD, K m , J 0 , J 45 , CD, and PD, the 95% LoA ranged from  -0.07 to 0.05 mm, -9.67 to 7.34 mm, -0.11 to 0.04 mm, -0.25 to 0.50 D, -0.22 to 0.20 D, -0.15 to 0.20 D, -0.23 to 0.35 mm and 1.55 to 3.77 mm, respectively., Conclusions: The measurements of AL, CCT, ACD, K m , corneal astigmatism, and CD showed a narrow LoA and may be used interchangeably in healthy subjects between the new OLCR optical biometer and the Scheimpflug/PCI biometer; however, a poor agreement was noted for PD values., (© 2024. The Author(s).)

Purpose: To evaluate the agreement of ocular biometry measured using a swept-source optical coherence (Casia 2) and a dual Scheimpflug (Galilei G6) tomography in keratoconus., Methods: This retrospective study included 102 eyes from 102 keratoconus patient examined using both devices. Parameters compared included flat (Kf) and steep (Ks) keratometry, astigmatism of anterior, posterior, and total keratometry, central (CCT) and thinnest (TCT) corneal thickness. To assess the agreement, intraclass coefficient (ICC) and Bland-Altman analysis with 95% limits of agreement (LoA) were used., Results: Anterior and total Ks and Kf showed moderate or good agreement with 95% limits of agreement (LoA) range over 9.75 D. Posterior Ks and Kf were lower in the Galilei G6 (all p < 0.001). Astigmatism showed moderate, poor, and moderate agreement for anterior, posterior, and total keratometry, respectively. CCT and TCT showed excellent agreement; however, the 95% LoA range was over 60 μm., Conclusion: The agreement between the two devices was not excellent for most parameters used to diagnose keratoconus and assess disease progression, and the differences were clinically significant. Therefore, the measurements from these two devices are not interchangeable for patients with keratoconus., (© 2024. The Author(s).)

The repeatability of two biometers (Lenstar-LS900 and Eyestar-900) to measure ocular parameters and intraocular lens (IOL) power calculation, and their agreement were evaluated. 134 eyes of 134 participants were measured thrice with each biometer. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT) and keratometry (K) were evaluated. The IOL power was calculated using different formulas. The repeatability limit (RLimit), the mean differences (MD) and the limits of agreement (LoA) were calculated. The RLimits for all parameters were higher with Lenstar compared to Eyestar. RLimits were lower than 0.50 D except for Barrett Universal II (0.54 D) and Haigis (0.51 D) formulas with the Lenstar. Mean differences were lower than 0.01 mm for AL, ACD and LT, and lower than 0.03 D for K. MD ranged from 0 to 0.02 D for all formulas except for Barrett and Hill. When dividing the sample into subgroups (short, normal and long eyes), the MDs were similar for the IOL power and were lower than 0.03 D, except for the Barrett and Hill formulas. Both biometers provide repeatable biometry and IOL power calculations. The LoA interval for the IOL power calculation was between 0.75 and 1.50D, which was similar among the subgroups., (© 2024. The Author(s).)

Purpose: To compare the biometric measurements obtained from the Pentacam AXL Wave, IOLMaster 700, and ANTERION and calculate the recommended intraocular lens power using the Barrett Formulae., Methods: This was a retrospective cross-sectional study of patients who underwent biometry using the Pentacam AXL Wave, IOLMaster 700, and ANTERION. Flat keratometry (K1), steep keratometry (K2), anterior chamber depth (ACD), and axial length (AL) from each device were measured and compared. These parameters were used to calculate the recommended IOL powers using the Barrett formula., Results: The study included 252 eyes of 153 patients. The IOLMaster had the highest acquisition rate among the two biometers. The Pentacam obtained the shortest mean AL, the IOLMaster measured the highest mean keratometry values, and the ANTERION measured the highest mean ACD. In terms of pairwise comparisons, keratometry and axial length were not significantly different between the Pentacam-IOLMaster and ANTERION-IOLMaster groups, while the rest of the pairwise comparisons were statistically significant. In nontoric and toric eyes, 35-45% of patients recommended the same sphere of IOL power. In another 30-40%, the Pentacam and ANTERION recommended an IOL power one step greater than that of the IOLMaster-derived data. 50% of the study population recommended the same toric-cylinder IOL power., Conclusions: The Pentacam AXL Wave, IOLMaster 700, and ANTERION can reliably provide data for IOL power calculations; however, these data are not interchangeable. In nontoric and toric eyes, 35-45% of cases recommended the same sphere IOL power, and in another 30-40%, the Pentacam and ANTERION recommended one-step higher IOL power than the IOLMaster-derived data. In targeting emmetropia, selecting the first plus IOL power is advisable when using the Pentacam and ANTERION to approximate the IOL power calculations recommended by the IOLMaster 700., (© 2024. The Author(s).)

Decoupling dynamic touch signals in the optical tactile sensors is highly desired for behavioral tactile applications yet challenging because typical optical sensors mostly measure only static normal force and use imprecise multi-image averaging for dynamic force sensing. Here, we report a highly sensitive upconversion nanocrystals-based behavioral biometric optical tactile sensor that instantaneously and quantitatively decomposes dynamic touch signals into individual components of vertical normal and lateral shear force from a single image in real-time. By mimicking the sensory architecture of human skin, the unique luminescence signal obtained is axisymmetric for static normal forces and non-axisymmetric for dynamic shear forces. Our sensor demonstrates high spatio-temporal screening of small objects and recognizes fingerprints for authentication with high spatial-temporal resolution. Using a dynamic force discrimination machine learning framework, we realized a Braille-to-Speech translation system and a next-generation dynamic biometric recognition system for handwriting., (© 2024. The Author(s).)

Purpose: To compare intraocular lens (IOL) power prediction accuracy of the Eyestar 900 (EyeS900) and the IOLMaster 700 (IOLM700) based on estimated and measured posterior corneal power., Design: Retrospective, interinstrument reliability study., Methods: Setting: Institutional., Participants: Two hundred twenty-five eyes of 225 cataract surgery patients., Measurements: Patients underwent measurements by both devices preoperatively., Main Outcome Measures: Spherical Equivalent Prediction Error (SEQ-PE), spread of the SEQ-PE (precision) and the absolute SEQ-PE (accuracy) of each device using Barrett Universal II (BUII) formula with either estimated posterior keratometry (E-PK) or measured posterior keratometry (M-PK)., Results: Trimmed mean SEQ-PEs of EyeS900 E-PK, EyeS900 M-PK, IOLM700 E-PK, and IOLM700 M-PK were 0.03, 0.08, 0.02, and 0.09 D, respectively with no significant differences between EyeS900 E-PK and IOLM700 E-PK (P = 0.31) as well as between EyeS900 M-PK and IOLM700 M-PK (P = 0.31). Statistically significant SEQ-PE differences were found when E-PK and M-PK were compared, regardless of the device used, showing hyperopic SEQ-PE in M-PK calculations. Excellent correlation and agreement in SEQ-PE were found between the devices for both E-PK (P < 0.001, r = 0.848, mean bias: +0.01 D, 95% LOA of -0.32 to +0.34 D) and M-PK (P < 0.001, r = 0.776, mean bias: -0.01 D, 95% LOA of -0.42 to +0.39 D). No significant differences were found comparing absolute SEQ-PE and precision of the devices., Conclusion: The Eyestar 900 and the IOLMaster 700 show comparable IOL power prediction accuracy by the BUII formula using either estimated or measured posterior keratometry. An adjusted lens factor may be required for BUII when utilizing measured posterior keratometry in both devices., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Clinical Relevance: Measuring axial length is key in the field of myopia development and control. Hence, the precision and agreement of commercially available biometers is of vital interest to understand their variability and interchangeability in the paediatric population., Background: Different biometers are available to measure axial length and monitor myopia progression in clinical practice. The purpose of this study was to assess the precision (repeatability and reproducibility) and agreement of the MYAH and AL-Scan biometers in a paediatric population., Methods: Three consecutive measurements were performed using MYAH and AL-Scan biometers in each subject by the same operator to test for repeatability. To test for reproducibility, two measurements were performed for each subject by two different observers with a 5-min interval between measurements. To test the agreement, each subject was measured once with each instrument., Results: A total of 187 subjects, with a mean age of 8.5 ± 0.3 years and mean spherical equivalent refractive error of +0.22 ± 0.77 D participated in the study. For the repeatability study, the within-subject standard deviation was 0.01 mm, and the repeatability limit was 0.04 mm for both instruments, with no statistically significant differences among repeated measures ( p  = 0.162 for MYAH and p  = 0.774 for AL-Scan). For the reproducibility study, the within-subject standard deviation was 0.01 mm and the repeatability limit was 0.04 mm. There were statistically significant differences for the repeated measures for the AL-Scan ( p  = 0.002) but not for the MYAH ( p  = 0.643). Regarding the agreement between both instruments, the 95% limit of agreement ranged from -0.04 to 0.05 mm, and the differences were statistically significant ( p  = 0.021)., Conclusions: The repeatability, reproducibility, and agreement of the MYAH and AL-Scan biometers seem optimal for following children with myopia.

Purpose: To investigate the repeatability and agreement of corneal astigmatism measurements in eyes with irregular corneal astigmatism component (ICAC) using four devices: IOLMaster 700 biometer, Lenstar 900 biometer, iTrace, and Pentacam., Design: Prospective cross-sectional reliability analysis., Methods: Sixty-four eyes (52 patients) with ICAC were examined three times using the four devices. The eye with ICAC in this study is defined as the cornea has a certain degree of irregular astigmatism (asymmetric and/or skewed bowtie pattern of corneal topography according to corneal topography classification), accompanied with total corneal higher-order aberrations in the 4 mm zone of 0.3 µm or greater. Corneal astigmatism was evaluated using three categories: anterior corneal astigmatism (ACA), posterior corneal astigmatism, and total corneal astigmatism (TCA). The repeatability was determined using the ∆Ast (arithmetic mean of vector differences among three repeated corneal astigmatism measurements). Bland-Altman plots and astigmatism vector analyses were employed to assess agreement., Results: The IOLMaster 700 (∆Ast = 0.27 ± 0.20 D) showcased higher repeatability in ACA measurements compared to iTrace (∆Ast = 0.37 ± 0.38 D, P = .040) and Pentacam (∆Ast = 0.50 ± 0.22 D, P < .001), and paralleled the performance of Lenstar 900 (∆Ast = 0.31 ± 0.26 D, P = .338). The Pentacam (∆Ast = 0.09 ± 0.07 D, P < .001) demonstrated superior repeatability in posterior corneal astigmatism, whereas the IOLMaster 700 (∆Ast = 0.33 ± 0.23 D, P < .001) excelled in TCA. The IOLMaster 700 exhibited good agreement with either Lenstar 900 or iTrace, characterized by narrow 95% limits of agreement and clinically acceptable vector differences. Conversely, vector differences between Pentacam and the other three devices in ACA and TCA measurements were clinically significant, exceeding 0.50 D (all P < .05)., Conclusions: In terms of repeatability of corneal astigmatism measurements in eyes with ICAC, the IOLMaster 700 and Lenstar 900 outperformed iTrace and Pentacam. While the IOLMaster 700 can be used interchangeably with either Lenstar 900 or iTrace, the Pentacam is not interchangeable with the other three devices., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: This study assessed the agreement of ocular parameters of patients with myopia measured using Colombo intraocular lens (IOL) 2 and IOLMaster 700., Methods: Eighty patients (male, 22; average age, 29.14 ± 7.36 years) with myopia (159 eyes) were included in this study in May 2023. The participants' axial length (AXL), central corneal thickness (CCT), lens thickness (LT), white-to-white distance (WTW), front flat (K1), steep (K2), mean (Km) corneal keratometry, astigmatism (Astig), J0 vector, and J45 vector were measured using the IOLMaster 700 and Colombo IOL 2. The measurements from both devices were compared using the generalized estimating equation, correlation analysis, and Bland-Altman plots., Results: With the Colombo IOL 2, lower values for K2 and J0 (odds ratio [OR] = 0.587, p = 0.033; OR = 0.779, p < 0.0001, respectively), and larger values for WTW, Astig, and J45 (OR = 1.277, OR = 1.482, OR = 1.1, all p < 0.0001) were obtained. All ocular measurements by both instruments showed positive correlations, with AXL demonstrating the strongest correlation (r = 0.9996, p < 0.0001). The intraclass correlation coefficients for AXL and CCT measured by both instruments was 0.999 and 0.988 (both p < 0.0001), and Bland-Altman plot showed 95% limits of agreement (LoA) of -0.078 to 0.11 mm and - 9.989 to 13.486 μm, respectively. The maximum absolute 95% LoA for LT, WTW, K1, K2, and J0 were relatively high, achieving 0.829 mm, 0.717 mm, 0.983 D, 0.948 D, and 0.632 D, respectively., Conclusions: In young patients with myopia, CCT and AXL measurements obtained with the Colombo IOL 2 and IOLMaster 700 were comparable. However, WTW, LT, corneal refractive power, and astigmatism values could not be used interchangeably in clinical practice., (© 2024. The Author(s).)

Purpose: To assess the feasibility of using multifunction instruments to measure axial length for monitoring myopia progression in children and adults., Methods: Axial length was measured in 60 children (aged 6-18 years) and 60 adults (aged 19-50 years) with multifunction instruments (Myah and Myopia Master) and stand-alone biometers (Lenstar LS900 and IOLMaster 700). Repeatability (measurements by the same examiner) and reproducibility (measurements by different examiners) were computed as the within-subject standard deviation (Sw) and 95% limits of agreement (LoA). Inter-instrument agreement was computed as intraclass correlation coefficients. The threshold for detecting myopic progression was taken as 0.1 mm. Measures were repeated only in children following the administration of 1% tropicamide to determine the impact of cycloplegia on axial length., Results: Overall, the IOLMaster 700 had the best repeatability in children (0.014 mm) and adults (0.009 mm). Repeatability Sw values for all devices ranged from 0.005 to 0.021 mm (children) and 0.003 to 0.016 mm (adults). In children, reproducibility fell within 0.1 mm 95% of the time for the Myah, Myopia Master and IOLMaster 700. Agreement among all devices was classified as excellent (ICC 0.999; 95% CI 0.998-0.999), but the 95% LoA among the Myah, Myopia Master and Lenstar LS900 was ≥0.1 mm. Cycloplegia had no statistically significant effect on axial length (all p > 0.13)., Conclusions: The Myah and Myopia Master multifunction instruments demonstrated good repeatability and reproducibility, and their accuracy was comparable to stand-alone biometers. Axial length measurements using different instruments can be considered interchangeable but should be compared with some caution. Accurate axial length measurements can be obtained without cycloplegia. The multifunction instruments Myah and Myopia Master are as well suited for monitoring myopia progression in children as the stand-alone biometers IOLMaster 700 and Lenstar LS900., (© 2024 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Purpose: The anterior segment in individuals with high myopia has different features compared to those without myopia. IOLMaster 700 and Oculus Pentacam AXL are two accurate optical biometers. Both devices measure the cornea differently and thus yield different results when measuring intraocular lens (IOL) power. The purpose of this study is to assess the agreement of the IOL power calculation between IOLMaster 700 and Oculus Pentacam AXL in patients with high myopia., Methods: A prospective, analytical cross-sectional study was conducted to assess the agreement between the IOL power calculation with IOLMaster 700 and Oculus Pentacam AXL. In this study, 44 eyes were examined using Oculus Pentacam AXL and IOLMaster 700, and IOL power was calculated using the Barret Universal II formula and the AMO Sensar AR40E. The Bland-Altman plot was used to evaluate the agreement between the two devices., Results: Based on the IOLMaster 700 examination, 44 eyes with high myopia had axial lengths ranging from 26.05 to 34.02 mm. The mean IOL power was 8.26 ± 4.755 and 8.58 ± 4.776 based on IOLMaster 700 and Oculus Pentacam AXL, respectively. The Bland-Altman plot revealed good agreement between the two devices, with a mean difference of -0.3182 in the IOL power calculation and a 95% LoA of 0.88099-0.24462 with a 95% confidence interval., Conclusion: Both devices showed good agreement in the IOL power calculation in patients with high myopia., (Copyright © 2024 Copyright: © 2024 Indian Journal of Ophthalmology.)

Purpose: To evaluate the repeatability of automatic measurements of a new anterior segment optical coherence tomographer (ANTERION; Heidelberg Engineering) and their agreement with an anterior segment optical coherence tomography device combined with Placido disc corneal topography (MS-39; CSO) in patients affected by keratoconus., Methods: Fifty-four consecutive patients were included. Three measurements were performed with the ANTERION and one with the MS-39. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (CoV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. The paired t -test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices., Results: Repeatability of ANTERION measurements was high, with an ICC greater than 0.98 for all parameters. Many parameters revealed a CoV of less than 1% and a CoV within 5% was obtained for astigmatism measurements. The ANTERION measured a significantly higher corneal power and the MS-39 more negative posterior keratometric values. These differences were mirrored by a moderate agreement for mean simulated keratometry and poor agreement for total corneal power and posterior keratometry., Conclusions: The ANTERION revealed high repeatability of automatic measurements and good agreement with the MS-39 for many parameters in patients affected by keratoconus, but for most parameters the two instruments cannot be considered interchangeable. [ J Refract Surg . 2024;40(7):e445-e452.] .

Purpose: Calculating the intraocular lens (IOL) in patients after corneal refractive surgery presents a challenge. Because an overestimation of corneal power in cases undergone this surgery leading to a subsequent under-correction of IOL power. However, recent advancements in technology have eliable measurement of total corneal power. The aim of this research was to assess the agreement in simulated keratometry (SimK) and total keratometry (TK) values between IOLMaster 700 and Pentacam AXL., Methods: The study involved 99 patients (99 eyes) undergone small incision lenticule extraction (SMILE) surgery. Each patient underwent scans using IOL Master 700 and Pentacam AXL. The following parameters were recorded: SimK1, SimK2, Total K1 (TK1), and Total K2 (TK2) for IOLMaster 700; and SimK1, SimK2, True Net Power (TNP) K1, TNPK2, Total Corneal Refractive Power (TCRP) K1, and TCRP K2 for Pentacam AXL. Agreement between the two devices was evaluated using Bland-Altman plot, while paired t-test was utilized to compare any differences in the same parameter by both instruments., Results: The results revealed a strong correlation between the two devices.Noticeable comparability was identified for all SimK variables. However, there were noticeable differences in TK measurements as well as TK1-TNPK1, TK2-TNP K2, TK1-TCRP K1, and TK2-TCRP K2 parameters when comparing the two devices. The IOLMaster 700 consistently measured steeper values than the Pentacam AXL, with significant and clinically relevant differences of 1.34, 1.37, 0.87, and 0.95 diopters, respectively., Conclusion: While there was a noticeable correlation between the IOLMaster 700 and Pentacam AXL in SimK measurements, a marked difference was noted in TK values. The two devices cannot be used interchangeably when quantifying TK values., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Objective: To evaluate the accuracy of two portable ultrasound machines (PUM) in assessing fetal biometry and estimated gestational age (EGA)., Methods: This was a secondary analysis of data from the Fetal Age Machine Learning Initiative, an observational study of pregnant women in the USA and Zambia. Each participant underwent ultrasound assessment by an experienced sonographer using both a high-specification ultrasound machine (HSUM) and a PUM (Butterfly iQ or Clarius C3) to measure fetal biometry and calculate EGA at each visit. By comparing paired PUM and HSUM scans, we estimated agreement between individual biometry measurements and aggregate gestational age estimates by reporting mean difference, intraclass correlation coefficient (ICC) and Bland-Altman plots, adjusting for trend., Results: Between April and December 2021, 818 participants contributed 1386 paired PUM-HSUM ultrasound investigations, of which 991 PUM scans were obtained using the Butterfly iQ device and 395 using the Clarius C3 device. Gestational age at scan ranged from 7 to 38 weeks. Compared with HSUM, the Butterfly iQ PUM had a mean difference of -0.20 (95% CI, -0.60 to 0.20) days in the first trimester and -0.68 (95% CI, -0.93 to -0.44) days in the second/third trimesters. Compared with HSUM, the Clarius C3 PUM had a mean difference of -0.47 (95% CI, -1.11 to 0.18) days in the first trimester and -1.67 (95% CI, -2.10 to -1.25) days in the second/third trimesters. ICCs were 0.989 or greater throughout. Increasing gestational age was associated with increasing error and absolute error in EGA and fetal biometry. Both PUM devices demonstrated a modest trend toward underestimation of EGA with advancing gestational age in second/third-trimester scans, compared with HSUM., Conclusion: The Butterfly iQ and Clarius C3 PUM devices were highly accurate in performing fetal biometry in a diverse population from the USA and Zambia. © 2023 International Society of Ultrasound in Obstetrics and Gynecology., (© 2023 International Society of Ultrasound in Obstetrics and Gynecology.)

Purpose: To compare two swept-source OCT optical biometers, the Anterion® (Heidelberg Engineering GmbH, Heidelberg, Germany) and the IOLMaster 700® (Carl Zeiss Meditec AG, Jena, Germany), in the analysis of biometric data, intraocular lens (IOL) calculation and postoperative spherical equivalent predictability., Methods: This was a real-life, single-center, retrospective study including 152 eyes of 81 consecutive patients referred for cataract surgery. All patients were examined with the IOLMaster 700® and the Anterion®. Biometric data (axial length [AL], anterior chamber depth [ACD], mean keratometry [Km], K1 [flat keratometry], K2 [steep keratometry] and axis, TK1 [flat total keratometry], TK2 [steep total keratometry], central pachymetry, lens thickness [LT], white-to-white distance [WTW]), IOL calculation with the SRK/T formula, and postoperative refractive outcome at 1 month were compared., Results: All biometric measurements were significantly different between the two biometers. Correlations were excellent for AL, pachymetry, ACD, LT and keratometry measurements, and for the IOL calculation (r>0.96, intraclass correlation coefficient=1). The IOL power for emmetropia was similar between both biometers when the SRK/T formula was used (20.84±3.24D versus 20.86±3.29D, P=0.61). The mean postoperative spherical equivalent prediction error calculated using the SRK/T formula was 0.03±0.5D for the IOLMaster 700® versus 0.01±0.47D for the Anterion® (P=0.12)., Conclusions: This study showed excellent correlation and agreement for the biometric measurements and the IOL power calculation with the SRK/T formula between both biometers., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

The aim of the study was to assess the external and internal compatibility of the Biometrics E-LINK EP9 evaluation system device in the area of hand grip and pinch strength in the Polish population. The testing of hand grip and pinch strength was carried out among 122 healthy students. Two examiners performed hand grip and pinch strength measurements with a Biometrics E-LINK EP9 evaluation system device. Measurements were made for the right and left hands. The same people were tested again two weeks later, under the same conditions. The scores of one rater on the first and second tests were compared for reproducibility, and the scores of the two raters were compared to assess the reliability of the instrument. The measurements were found to be highly consistent both between the investigators and between the tests in the hand grip dynamometer test. The findings show high values of the Pearson's correlation coefficient equal or close to 1, as well as the interclass correlation coefficient (ICC) >0.9. Analysis of pinch strength measurements performed using the pinchmeter also found high values of the Pearson's correlation coefficient close to 1, as well as the interclass correlation coefficient >0.9; this reflects high agreement between the measurements performed by two investigators as well as assessments performed by one investigator at time intervals. These findings were confirmed by analyses performed using Bland-Altman plots. The measurements made with the Biometrics E-link EP9 evaluation system show high internal and external consistency in hand grip and pinch strength assessment. Biometrics E-link EP9 can be recommended for daily clinical practice., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Leszczak et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Aims: To assess the repeatability and reproducibility of the ocular measurements obtained with the Suoer SW-9000 μm Plus, a new fully automatic biometer based on optical low coherence reflectometry (OLCR) biometer, and to compare them to those obtained by a swept-source optical coherence tomography (SS-OCT)-based biometer., Methods: This prospective study consisted of 115 eyes of 115 healthy subjects. The measurements were taken by the two optical biometers in random order. The measured parameters were axial length (AL), central corneal thickness (CCT), aqueous depth (AQD), anterior chamber depth (ACD), mean keratometry (Km), lens thickness (LT) and corneal diameter (CD). To evaluate the intraobserver repeatability and interobserver reproducibility, the within-subject SD, test-retest variability, coefficient of variation (CoV) and intraclass correlation coefficient (ICC) were adopted. The Bland-Altman plot was drawn to assess the agreement., Results: The repeatability and reproducibility of all parameters for the new device were excellent (ICC>0.960 and CoV<0.71%). The Bland-Altman plots showed high agreement between the OLCR-based and SS-OCT-based devices for AL, CCT, AQD, ACD, Km and LT, with narrow 95% limit of agreements (LoAs) (-0.08 mm to 0.06 mm, -15.91 µm to -1.01 µm, -0.09 mm to 0.09 mm, -0.09 mm to 0.08 mm, -0.47 D to 0.35 D, -0.05 mm to 0.16 mm, respectively) and moderate agreement for CD (95% LoA: -0.67 mm to -0.01 mm)., Conclusions: The new Suoer SW-9000 μm Plus biometer showed excellent repeatability and reproducibility. All the parameters obtained by this biometer were similar to those measured by SS-OCT-based biometer., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: To evaluate the repeatability of a new swept source optical coherence tomography (SS-OCT)-based biometer to measure anterior segment parameters and to assess the agreement with 3 other imaging devices based on different measurement principles., Setting: Unit of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden., Design: Prospective, comparative case series., Methods: 3 consecutive measurements were obtained in unoperated eyes with the Eyestar900 (SS-OCT), Lenstar 900, MS-39, and Sirius. The following anterior segment parameters were evaluated: central corneal thickness (CCT), corneal diameter (CD), aqueous depth (AQD), and corneal power metrics. The repeatability limit (Rlim), coefficient of variation (CoV), and a repeated measures Bland-Altman analysis were performed., Results: 74 eyes of 74 participants were measured. The Rlims for CCT, CD, and AQD were lower than 10 μm, 0.3 mm, and 0.10 mm for all devices, respectively. The corresponding CoVs for these parameters never exceeded 1.2%. The Rlim for the corneal power metrics never exceeded 0.60 diopter (D) for any of the instruments. Lenstar showed the best agreement with the MS-39 to measure CCT, CD, and AQD (limit of agreement interval, LoA: 15.54 μm, 0.55 mm, and 0.16 mm, respectively). The mean difference for keratometry parameters was lower than 0.3 D for all device comparisons, and the LoA interval ranged between 0.52 D and 1.21 D., Conclusions: The repeatability for measuring anterior segment parameters was good, and the agreement among all the instruments was good for CD and AQD measurements. However, for CCT and keratometer parameters, the instruments cannot be used interchangeably due to large LoA interval., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of ASCRS and ESCRS.)

To efficiently allocate medical resources at disaster sites, medical workers perform triage to prioritize medical treatments based on the severity of the wounded or sick. In such instances, evaluators often assess the severity status of the wounded or sick quickly, but their measurements are qualitative and rely on experience. Therefore, we developed a wearable device called Medic Hand in this study to extend the functionality of a medical worker's hand so as to measure multiple biometric indicators simultaneously without increasing the number of medical devices to be carried. Medic Hand was developed to quantitatively and efficiently evaluate "perfusion" during triage. Speed is essential during triage at disaster sites, where time and effort are often spared to attach medical devices to patients, so the use of Medic Hand as a biometric measurement device is more efficient for collecting biometric information. For Medic Hand to be handy during disasters, it is essential to understand and improve upon factors that facilitate its public acceptance. To this end, this paper reports on the usability evaluation of Medic Hand through a questionnaire survey of nonmedical workers., (© 2024. The Author(s).)

Purpose: To provide an up-to-date review of the agreement in automated white-to-white (WTW) measurement between the latest topographic and biometric devices., Methods: In this systematic review, PubMed, Web of Science, and Scopus databases were searched for articles published between 2017 and 2023, focusing on WTW agreement studies on adult, virgin eyes, with or without cataract and no other ocular comorbidities. Studies evaluating WTW measurements performed with autokeratometers, manual calipers, or manual image analysis were excluded. When available, the following metrics for the agreement of WTW measurements between pairs of devices were included: mean difference ± standard deviation, 95% limits of agreement (LoA), LoA width, 95% confidence interval (95 CI%), and intraclass correlation coefficient (ICC)., Results: Forty-one studies, covering comparisons for 19 devices, were included. Altogether, 81 paired comparisons were performed for 4,595 eyes of 4,002 individuals. The mean difference in WTW measurements between devices ranged from 0.01 mm up to 0.96 mm, with varying CI. The 95% LoA width ranged from 0.31 to 2.45 mm (median: 0.65 mm). The majority of pairwise comparisons reported LoA wider than 0.5 mm, a clinically significant value for phakic intraocular lens sizing., Conclusions: Nearly all analyzed studies demonstrated the lack of interchangeability of the WTW parameter. The corneal diameter, assessed by means of grayscale en-face image analysis, tended to demonstrate the lowest agreement among devices compared to other measured biometric parameters. [ J Refract Surg . 2024;40(3):e182-e194.] .

Context: Simulation-based education (SBE) has demonstrated its acceptability and effectiveness in improving ultrasound training. Because of the high cost of its implementation (investment in equipment and supervision), a pragmatic assessment of the transfer of skills learned in SBE to clinical practice and the identification of its optimal scheduling conditions have been requested to optimize its input., Objectives: To quantify the long-term impact of simulation-based education (SBE) on the adequate performance of ultrasound fetal biometry measurements (I). The secondary objective was to identify the temporal patterns that enhanced SBE input in learning (II)., Methods: Trainees were arbitrarily assigned to a 6-month course in obstetric ultrasound with or without an SBE workshop. In the SBE group, the workshop was implemented 'before' or at an 'early' or a 'late-stage' of the course. Those who did not receive SBE were the control group. The ultrasound skills of all trainees were prospectively collected, evaluated by calculating the delta between OSAUS (Objective Structured Assessment of Ultrasound Skills) scores before and after the course (I). Concomitantly, the accuracy of trainees' measurements was assessed throughout the course by verifying their correlation with the corresponding measurements by their supervisors. The percentage of trainees able to perform five consecutive sets of correct measurements in the control group and in each SBE subgroup were compared (II)., Results: The study included 61 trainees (39 SBE and 22 controls). Comparisons between groups showed no significant difference in the quantitative assessment of skill enhancement (difference in the pre- and post-internship OSAUS score: 1.09 ± 0.87 in the SBE group and 0.72 ± 0.98 in the control group) (I). Conversely, the predefined acceptable skill level was reached by a significantly higher proportion of trainees in the 'early' SBE subgroup (74%, compared with 30% in the control group, P<0.01)(II)., Conclusions: The quantitative assessment does not support the existence of long-term benefits from SBE training, although the qualitative assessment confirmed SBE helped to raise the minimal level within a group when embedded in an 'early' stage of a practical course., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Importance: Currently, there are no presymptomatic screening methods to identify individuals infected with a respiratory virus to prevent disease spread and to predict their trajectory for resource allocation., Objective: To evaluate the feasibility of using noninvasive, wrist-worn wearable biometric monitoring sensors to detect presymptomatic viral infection after exposure and predict infection severity in patients exposed to H1N1 influenza or human rhinovirus., Design, Setting, and Participants: The cohort H1N1 viral challenge study was conducted during 2018; data were collected from September 11, 2017, to May 4, 2018. The cohort rhinovirus challenge study was conducted during 2015; data were collected from September 14 to 21, 2015. A total of 39 adult participants were recruited for the H1N1 challenge study, and 24 adult participants were recruited for the rhinovirus challenge study. Exclusion criteria for both challenges included chronic respiratory illness and high levels of serum antibodies. Participants in the H1N1 challenge study were isolated in a clinic for a minimum of 8 days after inoculation. The rhinovirus challenge took place on a college campus, and participants were not isolated., Exposures: Participants in the H1N1 challenge study were inoculated via intranasal drops of diluted influenza A/California/03/09 (H1N1) virus with a mean count of 106 using the median tissue culture infectious dose (TCID50) assay. Participants in the rhinovirus challenge study were inoculated via intranasal drops of diluted human rhinovirus strain type 16 with a count of 100 using the TCID50 assay., Main Outcomes and Measures: The primary outcome measures included cross-validated performance metrics of random forest models to screen for presymptomatic infection and predict infection severity, including accuracy, precision, sensitivity, specificity, F1 score, and area under the receiver operating characteristic curve (AUC)., Results: A total of 31 participants with H1N1 (24 men [77.4%]; mean [SD] age, 34.7 [12.3] years) and 18 participants with rhinovirus (11 men [61.1%]; mean [SD] age, 21.7 [3.1] years) were included in the analysis after data preprocessing. Separate H1N1 and rhinovirus detection models, using only data on wearble devices as input, were able to distinguish between infection and noninfection with accuracies of up to 92% for H1N1 (90% precision, 90% sensitivity, 93% specificity, and 90% F1 score, 0.85 [95% CI, 0.70-1.00] AUC) and 88% for rhinovirus (100% precision, 78% sensitivity, 100% specificity, 88% F1 score, and 0.96 [95% CI, 0.85-1.00] AUC). The infection severity prediction model was able to distinguish between mild and moderate infection 24 hours prior to symptom onset with an accuracy of 90% for H1N1 (88% precision, 88% sensitivity, 92% specificity, 88% F1 score, and 0.88 [95% CI, 0.72-1.00] AUC) and 89% for rhinovirus (100% precision, 75% sensitivity, 100% specificity, 86% F1 score, and 0.95 [95% CI, 0.79-1.00] AUC)., Conclusions and Relevance: This cohort study suggests that the use of a noninvasive, wrist-worn wearable device to predict an individual's response to viral exposure prior to symptoms is feasible. Harnessing this technology would support early interventions to limit presymptomatic spread of viral respiratory infections, which is timely in the era of COVID-19.

Objective: To compare the biometric parameters provided by A-scan ultrasonography and the Lenstar optical biometer in guinea pig eyes, including anterior segment depth (ASD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL), and differences of them between treated form deprivation (FD) eyes and untreated fellow eyes after 4 weeks of FD., Methods: Three-week-old guinea pigs (N = 41) were subjected to biometric measurements before monocular FD (baseline) and after a 4-week FD. Statistical analyses including within-subject standard deviation (SD within ), coefficient of variation (CV), and intraclass correlation coefficient (ICC), used to evaluate repeatability for both the A-scan ultrasonography and the Lenstar individually, and correlation and Bland-Altman analyses were used to assess agreement between the two methods. The absolute values of ASD, LT, VCD and AL as measured by the two devices were compared, and the differences of them between treated (T) and untreated fellow (F) eyes (ΔASD, ΔLT, ΔVCD and ΔAL) (Δ = T-F) were compared between the two devices after 4 weeks of FD., Results: Measurements by the Lenstar (ICC: 0.923-0.994) were more repeatable than A-scan ultrasonography (ICC: 0.825-0.870). There was a high correlation for AL (r = 0.851, P < 0.001), a moderate correlation for VCD (r = 0.571, P < 0.001) and LT (r = 0.423, P < 0.001), and a low correlation for ASD (r = 0.230, P < 0.01) between the two devices. The values for ASD, VCD and AL measured by A-scan ultrasonography were larger than those measured by the Lenstar (all, P < 0.001), while LT provided by A-scan ultrasonography was much smaller than that of the Lenstar (P < 0.001). Bland-Altman plots showed poor agreement of absolute values of the four parameters between the two devices. Moreover, there was a high correlation between both methods for ΔAL (r = 0.704, P < 0.001), a moderate correlation for ΔVCD (r = 0.534, P < 0.001) and ΔASD (r = 0.574, P < 0.001), and no correlation for ΔLT (r = 0.303, P = 0.054). The ΔASD, ΔLT, and ΔAL measurements obtained by A-scan ultrasonography were greater than those obtained by the Lenstar (all, P < 0.001), while ΔVCD was mildly smaller using A-scan ultrasonography (P < 0.05). Bland-Altman plots illustrated there is good agreement of ΔAL, ΔVCD, ΔASD, and ΔLT between the two devices., Conclusions: The Lenstar exhibited better repeatability and provided smaller measurements for AL, VCD and ASD than A-scan ultrasonography. Furthermore, a high correlation and a good agreement for the ΔAL was observed between the two devices after a period of FD. In summary, the two devices cannot replace each other directly to obtain absolute values of ASD, LT, VCD and AL, but the Lenstar still can serve as an option in measuring ΔAL between eyes in guinea pig myopia model., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the feasibility and repeatability of Lenstar LS 900 biometry measurements in a paediatric population., Methods: Children were examined as part of the LIFE Child Study (Leipzig Research Centre for Civilization Diseases), a population-based study in Leipzig, Germany. Altogether, 1917 children, aged from 3.5 to 17.5 years, were assessed with the Haag Streit Lenstar LS 900. Three consecutive measurements of the right eye were analysed for axial length, central corneal thickness, anterior chamber depth, aqueous depth, lens thickness and flat and steep corneal radii. The number of successful measurements and repeatability were evaluated for each parameter and three age bands (3.5 to 6.5 years, 6.5 to 10.5 years and 10.5 to 17.5 years)., Results: Best measurement feasibility was found for axial length and central corneal thickness (91% to 100%), followed by flat and steep corneal radii (86% to 100%), anterior chamber and aqueous depth (76% to 92%) and lens thickness (50% to 81%), with higher numbers for older children. Repeatability values (in mm) were: axial length 0.025 to 0.035; central corneal thickness 0.003 to 0.027; aqueous depth 0.024 to 0.058; anterior chamber 0.024 to 0.054; lens thickness 0.034 to 0.067. An overall trend showed better repeatability for older children, especially for central corneal thickness, aqueous depth and lens thickness., Conclusions: For ocular biometry in the paediatric population, axial length, central corneal thickness, flat and steep corneal radii can be measured very reliably even in children from 4 years old onward using the Lenstar LS 900. Lens thickness can be quantified in a limited number of younger children. Repeatability was high for all variables investigated. Repeatability improved with age, reaching adult values in the adolescent age band. Established repeatability limits can be applied in future studies as a quality parameter., (© 2021 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Purpose : To evaluate the agreement of different biometric parameters obtained using intraoperative spectral-domain optical coherence tomography (SD-OCT) and two swept-source optical coherence tomography (SS-OCT) based biometers. Methods : 102 eyes were assessed using the intraoperative SD-OCT integrated into the Catalys femtosecond-laser, and the IOLMaster 700 and Anterion SS-OCT-based-biometers. Central corneal thickness (CCT), anterior chamber depth (ACD), white-to-white (WTW), and lens thickness (LT) were measured. Results : There were statistically significant differences for CCT, ACD, WTW and LT between devices (p < 0.001). The mean difference for ACD ranged from -0.067 to -0.250 mm, with the largest mean difference being between the IOLMaster 700 and Catalys. CCT mean differences ranged from 7 to 32 µm, with the largest mean difference being between the Anterion and Catalys. For WTW, the comparison between the IOLMaster 700 vs Catalys showed the largest mean difference (0.38 mm). However, the mean differences for LT from all three devices were quite similar, ranging from -0.02 to -0.08 mm. Conclusions : SS-OCT biometers showed good agreement for ACD, CCT, WTW and LT. The SD-OCT showed ACD, CCT and WTW values that do not seem to be interchangeable with the SS-OCT biometers; however, this device did show excellent agreement in the case of LT.

The aim of this study was at examining the validity and reliability of a marketed bioimpedance (BIA) scale for body composition assessment, in children engaged in an educational football project (FIFA 11 for Health). One-hundred and twenty-seven children (70 boys and 57 girls; age 10.7±0.5 years, body mass 41.2±9.0 kg, Body mass index 18.5±3.3 kg·m-2 and stature 149±7 cm) were evaluated for total body mass, lean body mass, muscle mass, using BIA (InBody 270, Biospace, California, USA) and dual-energy X-ray absorptiometry (DEXA, Lunar Prodigy, GE Medical Systems, Madison, Wisconsin, USA), at baseline conditions. Data analyses were carried out separately for girls and boys. Nearly perfect associations (r = 0.97-0.99) and excellent absolute (TEM = 0.04-1.9%) and relative (ICC = 0.98-1.00) inter-device reliability were found between DEXA and BIA variables. Fat and lean body mass bias (p < .0001) were practically relevant both for the boys (2.56 and 11.22 kg, respectively) and the girls (2.33 and 10.49 kg, respectively). Muscle mass and body fat were underestimated and overestimated, respectively, for the boys and girls. InBody 270 is a valid BIA system for estimating body composition with an excellent inter-device relative and absolute reliability. However, the remarkable measurements bias of BIA fat and muscle mass values discourage its use for clinical prescription. The BIA body composition biases were sex dependent., Competing Interests: No competing interest.

Conformal integration of an epidermal device with the skin, as well as sweat and air permeability, are crucial to reduce stress on biological tissues. Nanofiber-based porous mesh structures (breathable devices) are commonly utilized to prevent skin problems. Noble metals are normally deposited on nanomesh substrates to form breathable electrodes. However, these are expensive and require high-vacuum processes involving time-consuming multistep procedures. Organic materials are suitable alternatives that can be simply processed in solution. We report a simple, cost-effective, mechanically biocompatible, and breathable organic epidermal electrode for biometric devices. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is sprayed on a nanofiber-mesh structure, treated using only heat and water to enhance its biocompatibility and conductivity, and used as the electrode. The treatment is accomplished using an autoclave, simultaneously reducing the electrical resistance and sterilizing the electrode for practical use. This research can lead to affordable and biocompatible epidermal electrodes with improved suitability for various biomedical applications.

Purpose: To assess the influence of artificial tears of different viscosity on K-readings prior to cataract surgery., Design: Prospective randomized crossover, before-and-after clinical study., Methods: Setting: Department of Ophthalmology, Medical University of Vienna., Patient Population: A total of 123 eyes of 80 patients prior to cataract surgery were assigned to 2 groups based on normal and dry eyes., Intervention: Two native baseline keratometries were followed by instillation of either high- or low-viscosity eye drops. Keratometry was repeated 30 seconds, 2 minutes, and 5 minutes after instillation., Main Outcome Measures: Influence of eye drops of different viscosity in normal and dry eyes on short time K-readings., Results: Repeatability between native baseline measurements was high (standard deviation = 0.02 mm in normal and in dry eyes). In normal and dry eyes, a statistically significant increase in measurement variability after instillation of both low-viscosity and high-viscosity eye drops was observed (P < .01). Measurement variability was most pronounced between baseline measurement and 30 seconds and diminished over time. Variability of K-readings appeared higher in dry eyes compared with normal eyes. Astigmatism changed more than 0.5 diopters in 13.2% of normal eyes and 34.4% in dry eyes using eye drops of high viscosity., Conclusion: Tear film-stabilizing eye drops prior to keratometry measurements influenced K-readings significantly, especially in dry eyes. A time period of more than 5 minutes should be allowed to pass after instillation of eye drops. The higher the viscosity of the eye drops, the stronger the influence and the longer its persistence., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background/aims: This study assessed the feasibility of a novel contact lens device for intraocular pressure (IOP) and ocular pulse amplitude (OPA) continuous measurements over 24 hours., Methods: This prospective, open-label, single-centre, non-randomised study included glaucoma and healthy subjects. IOP and OPA values acquired by the pressure-measuring contact lens (PMCL) device in one patient's eye at the beginning of the measurement were compared with tonometry values (Goldman applanation tonometry (GAT) and dynamic contour tonometry (DCT)) in the same eye just before PMCL placement. Furthermore, IOP and OPA values measured with PMCL on the study eye during a water drinking test (WDT) were compared with DCT values in the fellow eye. Comparisons were performed using t-tests with 95% Confidence Intervals., Results: Twenty-four-hour IOP and OPA curves were obtained for eight subjects. The mean IOP difference between PMCL and tonometry on the same eye was within ±5 mm Hg in 75% (GAT) and 87.5% (DCT) of subjects. IOP variations due to WDT were detected by PMCL and DCT, showing an average increase of 2.43 and 1.85 mm Hg, respectively. Differences between PMCL and DCT for IOP variations in fellow eyes were within ±5 mm Hg for 97.2% of time points. The difference between OPA in fellow eyes was within ±5 mm Hg for 85.5% of the time points., Conclusions: This first-in-human study is a proof-of-concept for 24-hour continuous measurements of IOP and OPA with the PMCL. This device is non-invasive and has good comparability with standard tonometry., Competing Interests: Competing interests: TV, SS-Z, MS and SC are employees of Sensimed. KM is a consultant for Sensimed., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Recently, biosensors have been used in an increasing number of different fields and disciplines due to their wide applicability, reproducibility, and selectivity. Three large disciplines in which this has become relevant has been the forensic, biometric, and cybersecurity fields. The call for novel noninvasive biosensors for these three applications has been a focus of research in these fields. Recent advances in these three areas has relied on the use of biosensors based on primarily colorimetric assays based on bioaffinity interactions utilizing enzymatic assays. In forensics, the use of different bodily fluids for metabolite analysis provides an alternative to the use of DNA to avoid the backlog that is currently the main issue with DNA analysis by providing worthwhile information about the originator. In biometrics, the use of sweat-based systems for user authentication has been developed as a proof-of-concept design utilizing the levels of different metabolites found in sweat. Lastly, biosensor assays have been developed as a proof-of-concept for combination with cybersecurity, primarily cryptography, for the encryption and protection of data and messages.

Background: The objective of this study was to compare the central corneal curvature and astigmatism measurements obtained with three different systems in healthy eyes and to assess the level of interchangeability between them., Methods: This was a comparative study examining 30 healthy eyes of 30 patients (age 15-53 years). A complete eye examination was performed in all cases including analysis of anterior corneal curvature and astigmatism with three devices: the colour-LED topography system Cassini (i-Optics) (CAS), the Scheimpflug-based system Pentacam (Oculus Optikgeräte) (PTC) and the optical biometer IOL-Master 500 (Carl Zeiss Meditec) (IOLM). Differences between devices in terms of curvature in the flattest (flat K) and steepest meridians (steep K) as well as in the magnitude (AST) and power vector components of astigmatism (J 0 and J 45 ) were evaluated. The interchangeability between devices was evaluated with the Bland-Altman method., Results: Statistically significant differences between devices were found in steep K and flat K (p < 0.001). No statistically significant differences between devices were found in AST (p = 0.057) and J 0 power vector (p = 0.185). However, differences between devices in J 45 did reach statistical significance (p = 0.039). Ranges of agreement for curvature measures ranged from 0.123 (flat K, CAS-PTC) to 0.165 mm (steep K, CAS-PTC). Ranges for the magnitude of astigmatism were 0.868, 1.059 and 0.739 D in CAS-IOLM, PTC-IOLM and CAS-PTC comparisons, respectively. For J 0 and J 45 , ranges of agreement were below 0.522 D., Conclusions: Measurements of central corneal curvature and astigmatism obtained with the three devices evaluated cannot be used interchangeably., (© 2019 Optometry Australia.)

We studied the use of a rotating multi-layer 3D Light Detection And Ranging (LiDAR) sensor (specifically the Velodyne HDL-32E) mounted on a social robot for the estimation of features of people around the robot. While LiDARs are often used for robot self-localization and people tracking, we were interested in the possibility of using them to estimate the people's features (states or attributes), which are important in human-robot interaction. In particular, we tested the estimation of the person's body orientation and their gender. As collecting data in the real world and labeling them is laborious and time consuming, we also looked into other ways for obtaining data for training the estimators: using simulations, or using LiDAR data collected in the lab. We trained convolutional neural network-based estimators and tested their performance on actual LiDAR measurements of people in a public space. The results show that with a rotating 3D LiDAR a usable estimate of the body angle can indeed be achieved (mean absolute error 33.5 ° ), and that using simulated data for training the estimators is effective. For estimating gender, the results are satisfactory (accuracy above 80%) when the person is close enough; however, simulated data do not work well and training needs to be done on actual people measurements.

Purpose: To evaluate the agreement between measurements obtained with a new optical biometer (Argos; Movu Inc) using large coherence length swept-source optical coherence tomography (SS-OCT) and those obtained with an optical biometer with a rotating Scheimpflug camera, combined with partial coherence interferometry (PCI) (Pentacam AXL; Oculus Optikgeräte GmbH) in adults., Methods: The following measurements were examined and evaluated: axial length, central corneal thickness (CCT), anterior chamber depth (ACD), mean keratometry, J 0 and J 45 vectors, and corneal diameter. Measurements with the two biometers were conducted in triplicate per instrument in a random order by the same examiner. Paired t tests were employed to compare the difference between the two devices. The Bland-Altman method was implemented to assess their agreement., Results: A total of 145 patients were enrolled in the study. The differences between the Scheimpflug/PCI-based biometer and the SS-OCT biometer were as follows: -0.02 ± 0.05 mm for axial length, 1.15 ± 5.79 µm for CCT, -0.04 ± 0.04 mm for ACD, -0.28 ± 0.16 diopters (D) for mean keratometry, 0.01 ± 0.11 D for J 0 , -0.02 ± 0.10 D for J 45 , and -1.03 ± 0.62 mm for corneal diameter. Bland-Altman plots showed narrow ranges in axial length, CCT, ACD, mean keratometry, and J 0 and J 45 , which implied excellent agreement between the two biometers. Corneal diameter displayed poor agreement, with a 95% limits of agreement ranging from -2.25 to 0.19 mm., Conclusions: Excellent agreement was established between the measurements provided by the new optical biometer based on SS-OCT and the optical biometer using Scheimpflug imaging and PCI, except for corneal diameter. [J Refract Surg. 2020;36(7):459-465.]., (Copyright 2020, SLACK Incorporated.)

Purpose: To assess the repeatability of ocular biometric parameters using a high-resolution imaging device., Methods: 74 healthy right eyes were included in this study. Five-repeated measurements were taken with ANTERION high-resolution swept-source optical coherence tomographer (SS-OCT) to measure: corneal thickness (central and at 2, 4 and 6-mm diameters), aqueous depth (AD), lens thickness (LT), anterior chamber volume (ACV), axial length (AL), and pupil (diameter and position). The intrasubject standard deviation (S w ), coefficient of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated. Bland-Altman method was applied to analyze the difference between the first and the last measurement. The average and the difference between both measurements were calculated for all parameters., Results: We have not found statistically significant differences between repeated measurements (p > 0.05). The mean difference for corneal thickness was between -0.08 and 0.28 μm. For AD and LT was 0.004 and -0.004 μm, respectively. ACV mean difference was -0.03 mm 3 and for AL was 0.001 mm. Pupil diameter and position mean differences ranged between -0.008 and 0.009 mm. Overall, most ocular parameters had a S w <1 and a CoR <2 in their respective units, and an ICC >0.92., Conclusions: The ANTERION high-resolution SS-OCT device provides good repeatability for different ocular biometric measurements.

Purpose: To evaluate the repeatability and validity of total corneal power measurements (total keratometry [TK]) obtained with a recently introduced optical biometer (IOLMaster 700, Carl Zeiss Meditec AG) to a Scheimpflug device (Pentacam, Oculus)., Setting: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany., Design: Prospective randomized controlled trial., Methods: The inclusion criteria were a corneal astigmatism of 3.00 diopters (D) or less, no previous ocular surgery, no known corneal irregularities, and no known dry eyes. All eyes were measured 3 times using the optical biometer and the Scheimpflug device. The results were statistically compared using Bland-Altman, within-subject SD, and astigmatism vector analysis., Results: Ninety-three eyes of 93 subjects were included. Overall, the repeatability of all eyes measured was 0.42 for standard K, 0.40 for TK, 0.45 for total corneal refractive power (TCRP), 0.43 for true net power (TNP), and 0.39 for simulated K. Bland-Altman analysis showed no significant difference between the optical biometer's TK compared with standard K and the Scheimpflug device's simulated K, TNP, and TCRP, the P value exceeding .05 in each case. A difference of >0.50 diopters between astigmatism measurements between TK and TCRP was found in 10 cases compared with standard K and TNP with 0 and 2 cases., Conclusions: Repeatability of both devices was high, although measurements of meridian showed a great variability, suggesting that numerous measurements are needed to enhance accuracy. TCRP measurements between recently introduced TK and TCRP cannot be used interchangeably. Future studies are necessary to evaluate which measurement will result in a better outcome when respective measurements are used for toric intraocular lens calculations.

Purpose: To evaluate axial length (AL) measurements and detection rates using a swept-source optical coherence tomography (SS-OCT) biometer (OA-2000) compared with the IOLMaster, LENSTAR, and ultrasound (US) measurements in eyes with vitreous hemorrhage., Setting: Eye Hospital of Wenzhou Medical University, China., Design: Comparative evaluation of a diagnostic test or technology., Methods: Patients were adults with vitreous hemorrhage in one or both eyes. Lens Opacities Classification System III was used to determine they type and severity of cataract and the Forrester system was used to classify the grade of vitreous hemorrhage. The AL measurement was taken with the OA-2000, IOLMaster (v5.4), and LENSTAR (v2.1), and with US (Axis-II). The Bland-Altman test was used to assess the agreement between devices., Results: Forty eyes were scanned with each of the 4 biometers. For Forrester grade III, the detection rate was 100%, 41.7%, and 41.7% with the OA-2000, IOLMaster, and LENSTAR, respectively. For Forrester grades I and II, the detection rate was 46.4%, 3.57%, and 3.57% with the OA-2000, IOLMaster, and LENSTAR, respectively. The detection rate with US was 100% for all grades. The Bland-Altman limits of agreement between the 4 biometers indicated an excellent agreement: OA-2000 vs IOLMaster (95% limits of agreement -0.15 to 0.05 mm), OA-2000 vs LENSTAR (-0.04 to 0.12 mm), and OA-2000 vs US (-0.3 to 0.56 mm)., Conclusions: In vitreous hemorrhage, the detection rate with the SS-OCT OA-2000 biometer was better than that with the IOLMaster and LENSTAR. In cases in which all biometers were able to acquire an AL measurement an excellent agreement was found.

Randomized clinical trials are designed to estimate the average treatment effect (ATE). If heterogeneity of treatment effect exists, then it is possible that there may be subjects who derive a treatment effect different from the ATE. We propose a method to test the hypothesis that there exist subjects who derive benefit (or harm) against the null hypothesis that the treatment has no benefit (or harm) on each of the smallest sub-populations defined by discrete baseline covariates. Our approach is nonparametric, which generates the null distribution of the test statistic by the permutation principle. A key innovation of our method is that stochastic simulation is built into the test statistic to detect signals that may not be linearly related to the multiple covariates. This is important because, in many real clinical problems, the treatment effect is not linearly correlated with relevant baseline characteristics. We applied the method to a real randomized study that compared the Implantable Cardioverter Defibrillator (ICD) with conventional medical therapy in reducing total mortality in a low ejection fraction population. Simulations and power calculations were performed to compare the proposed test with existing methods.

This prospective cross-sectional study aimed to evaluate the agreement of two new biometers for measuring ocular biometric parameters in young healthy eyes. Ocular biometric parameters were measured using IOLMaster 700 and OA-2000. Power vector analyses of Cartesian (J0) and oblique (J45) components of corneal astigmatism were performed. The right eyes of 103 healthy volunteers were analyzed. The 95% limits of agreement ranged from -0.03 to 0.03 mm, -0.08 to 0.07 mm, -0.18 to 0.18 diopters (D), -1.09 to 1.16 D, -1.18 to 1.15 D for axial length (AL), anterior chamber depth (ACD), mean keratometry, J0 and J45 respectively, which were all comparable between the two biometers, while significant differences were detected in lens thickness (LT), central corneal thickness (CCT), white-to-white (WTW) and pupil diameter (PD). Predicted intraocular lens (IOL) powers were comparable between the two biometers by Haigis and Barrett Universal II formulas, while not by SRK/T, Hoffer Q and Holladay 2. Excepting CCT, WTW and PD meaurements, IOLMaster 700 and OA-2000 have excellent agreement on ocular biometric measurements and astigmatism power vectors, which provides more options for ocular biometric measurements and enables constant optimization for IOL power calculation.

Purpose : To evaluate the intrasession repeatability of the biometric measurements obtained with a low-coherence reflectometry optical biometer in pseudophakic eyes implanted with two different types of intraocular lens (IOL). Methods : Prospective, single-center, comparative study including 69 eyes of 69 patients with ages ranging from 51 to 92 years. Previous uncomplicated cataract surgery had been performed in all patients 1 to 2 months before measurements, with implantation of the Acrysof SN60WF IOL in 35 eyes (35 patients, group 1) and the IOL Akreos MI60 in 34 eyes (34 patients, group 2). A complete postoperative ophthalmological examination was performed including three consecutive measurements with the "Aladdin" system from (Topcon, Japan). Intrasession repeatability of axial length (AXL), anterior chamber depth (ACD) and IOL thickness (IOLT) were assessed with the within-subject standard deviation (S w ), intraobserver precision (1.96 × S w ), coefficient of variation (CV) and intraclass correlation coefficient (ICC). Results : The S w for AXL measurements was 0.03 and 0.05 mm in groups 1 and 2, respectively, with ICC of 1.000 and 0.999 (CV: 0.14% and 0.22%) (p ≤ 0.031). Concerning pseudophakic ACD, the S w was 0.03 and 0.09 mm in groups 1 and 2, respectively, with ICC of 0.992 and 0.956 (CV: 0.55% and 1.75%) (p ≤ 0.021). The variability of IOLT measurements was high in both groups, with S w of 0.12 and 0.29 mm for groups 1 and 2 ( p = .008), respectively, and ICC of 0.065 and 0.770 (CV: 20.84% and 62.39%). Conclusions : The optical biometer "Aladdin" (Topcon, Japan) provides consistent measurements of AXL and ACD in pseudophakic eyes. However, there is a limitation in the consistency of IOLT measurements that should be investigated further.

Objective: To compare the keratometric measurements of the Verion image guided system with the partial coherence interferometry (IOLMaster700) and the scheimpflug corneal topography (Pentacam). Methods: In this cross-sectional study, 146 eyes of 88 patients [mean age, (69±10) years; 62 eyes of male patients and 84 eyes of female patients] with cataract were examined before cataract extraction and IOL implantation surgery in the Tenth People's Hospital Affiliated to Tongji University from January 2016 to March 2017. Corneal curvature values acquired by the Verion optical imaging system were compared with the IOLMaster700 and the Pentacam. Keratometric data, magnitude of astigmatism, and steep astigmatic axis measurements from all three instruments were also compared. According to the steep axis of astigmatism, the eyes were divided into groups of with the rule (WTR), against the rule (ATR), and oblique astigmatism. The parameter differences between the Verion and the other devices in the three groups were analyzed. The data were evaluated using repeated measures analysis of variance and Bland-Altman plots. Results: The values of steep keratometry (Ks) of the Verion, IOLMaster700, and Pentacam were (44.60±1.32), (44.73±1.37), (44.43±1.35) D, respectively. The values of flat keratometry (Kf) of the Verion, IOLMaster700, and Pentacam were (43.51±1.41), (43.51±1.52), (43.40±1.45) D, respectively. The values of mean keratometry (Km) of the Verion, IOLMaster700, and Pentacam were (44.60±1.32), (44.12±1.35), (43.92±1.34) D, respectively. The values of astigmatism magnitude were (1.09±0.87), (1.24±1.02), (1.04±0.80) D, respectively. The F values were 1.81, 0.31, 0.93 and 2.22 in relation to Ks, Kf, Km and corneal astigmatism magnitude among the three instruments, respectively (all P >0.05). The 95% confidence intervals of Kf, Ks and astigmatism magnitude between the Verion and the other two devices were -1.10 to 0.80 D, -0.55 to 0.88 D; -1.10 D to 1.10 D, -0.80 to 1.04 D; -1.21 to 0.90 D, -0.92 to 1.02 D. The outcomes were considered acceptable. There were no statistically differences in steep astigmatic axis measurements between the Verion and the other two instruments among the WTR (62 eyes), ATR (45 eyes) and oblique (15 eyes) groups ( F= 0.63, 0.37; P= 0.54, 0.72, respectively). Conclusions: The Verion image guided system is a reliable system for the measurement of keratometry values and astigmatism. The keratometric power, magnitude and steep axis of astigmatism have no significant difference, and there is a good agreement among the Verion, IOL Master 700, and Pentacam. (Chin J Ophthalmol, 2020, 56: 47 - 52) .

Purpose: To analyze the results of intraocular lens (IOL) power calculation using measurements by a swept-source optical coherence tomography (SS-OCT) optical biometer., Setting: IRCCS G.B. Bietti Foundation, Rome, Italy., Design: Evaluation of a diagnostic test instrument., Methods: Preoperative measurements by the OA-2000 (Tomey Inc.) were taken in a consecutive series of patients undergoing cataract surgery with one IOL model (AcrySof SN60WF; Alcon Laboratories, Inc.). Measurements were entered into the following formulas: Barrett Universal II, Emmetropia Verifying Optical (EVO), Haigis, Hoffer Q, Holladay 1, Holladay 2, Holladay 2 with axial length adjustment, Kane, Olsen, Panacea, SRK/T, T2, and VRF. When refraction was measured at 1 month postoperatively, the mean arithmetic prediction error, the median absolute error (MedAE), and the percentage of eyes with a error of ±0.50 D or less were calculated after constant optimization., Results: We enrolled 150 eyes. All formulas yielded excellent outcomes. The MedAE ranged between 0.200 D and 0.259 D, with a statistically significant difference among formulas (P = .0004). The lowest MedAE values were obtained with the Barrett, EVO, Kane, Olsenstandalone, Radial Basis Function (RBF), and T2 formulas. The percentage of eyes with a prediction error of ±0.50 D or less ranged between 80.00% and 90.67%, with a statistically significant difference (P < .0001). The Barrett, EVO, Holladay 2 with axial length adjustment, Kane, RBF, and T2 achieved the highest percentages (≥88%)., Conclusions: Measurements provided by the SS-OCT optical biometer enable accurate IOL power calculation because all formulas yielded a prediction error within 0.50 D in at least 80% of eyes.

Objectives: To assess the agreement of corneal power, corneal astigmatism, axis location, and astigmatic vector component measurements using a Lenstar LS900, a T-cone add-on, and an ARK 1S autorefractor, furthermore, to assess instrument agreement in a subset of astigmatic eyes., Methods: Retrospective analysis of keratometric readings from 3 instruments for 66 eyes undergoing cataract surgery at the Maryland Veterans Affairs Medical Center from November 2014 to 2015. Agreement in corneal power, mean corneal power, axis location, and astigmatic vector components (J0, J45) between devices was evaluated. Comparability was assessed using intraclass correlation, analysis of variance (ANOVA) one-way analysis, Bland-Altman analysis, and power vector analysis. Intraclass correlation was then assessed for a subset of 42 eyes with corneal astigmatism greater than or equal to 1 D., Results: The intraclass correlation between instruments was 0.941 for corneal power, 0.788 for corneal astigmatism, 0.932 for J0, and 0.809 for J45. The ANOVA one-way repeated P values comparing Kf, Ks, Km, corneal astigmatism, axis location, J0, and J45 were all greater than 0.05. Power vector analysis showed nearly all values between instruments to be within ±0.5 D. Finally, the intraclass correlation between instruments in eyes with ≥1 D of corneal astigmatism as measured by the T-cone was 0.946 for corneal power, 0.837 for corneal astigmatism, 0.948 for J0, and 0.950 for J45., Conclusions: The high level of agreement between all devices indicates the instruments may be used interchangeably. Our data suggest that this may also be true for the subset of eyes with greater than or equal to 1 D in astigmatism, highlighting the toric intraocular lens population.

Purpose: To compare the repeatability and agreement between a swept-source biometer and a Scheimpflug biometer in cataract patients., Methods: Three consecutive measurements were obtained using a swept-source biometer (IOLMaster 700) and a Scheimpflug biometer (AL-Scan) in 52 eyes of 52 patients. Keratometry, central corneal thickness (CCT), anterior chamber depth (ACD), axial length, and white-to-white (WTW) distance were recorded. Astigmatism values were transformed into vector components of J0 and J45. Intraoperator repeatability was analyzed using intraclass correlation coefficients (ICCs) and reproducibility coefficients (RCs). Agreement of measurements between the two devices was evaluated using the Bland-Altman method., Results: The IOLMaster 700 showed higher ICCs and lower RCs for the mean keratometry (Km) (P≤0.018), CCT (P≤0.027), and ACD (P≤0.001) measurements, whereas the AL-Scan showed higher ICC and lower RC for the J45 vector component of astigmatism at the 2.4-mm zone (P≤0.034). Both the devices had excellent repeatability (ICC=0.999) in axial length measurement. Systematic differences were found in Km, CCT, ACD, and WTW (P≤0.018) between the devices. The mean difference for Km was -0.196 and -0.144 D measured at the 2.4-mm zone and 3.3-mm zone, respectively. The corresponding mean difference for CCT, ACD, and WTW distance was 14.92 μm, -0.017 mm, and 0.283 mm, respectively. These differences led to a statistically significant but clinically insignificant difference in the prediction of intraocular lens power., Conclusions: This study showed significant differences in anterior segment measurement repeatability and agreement between a swept-source biometer and a Scheimpflug biometer in eyes with cataract.

Objective: To evaluate whether an automated tool can recognize a structure of interest and measure fetal head circumference (HC), abdominal circumference (AC) and femur length (FL) on frozen two-dimensional ultrasound images., Methods: Ultrasound examinations were performed in 100 singleton pregnancies between 20 and 40 weeks of gestation, ensuring an even distribution throughout gestational age. In each pregnancy, three standard biometric variables (HC, AC, FL) were measured each in three different images obtained for this purpose (i.e. nine independent image acquisitions). An algorithm (Philips Research) was used to detect the structure of interest and automatically place calipers for measurement. Caliper placement was assessed in two ways. First, subjective clinical assessment was performed to determine whether the caliper placement was correct, and caliper position was classified as 'acceptable for clinical use', 'minor adjustment required' or 'major adjustment required'. Second, the resulting automatic measurements were compared with manual measurements, taken in real time. Mean difference errors were calculated and expressed as percentages to correct for fetal growth with advancing gestation., Results: After exclusion of one pregnancy due to missing images, a total of 891 images (297 for each biometric variable) from 99 pregnancies were analyzed. The algorithm failed to place calipers for the AC in nine images, whereas there were no failures in caliper placement for measurement of HC and FL. On subjective quality assessment of automatic caliper placement, in 475 (53.3%) images position of the calipers was judged to be clinically acceptable and did not require any adjustment, while in 317 (35.6%) and 90 images (10.1%) minor and major adjustments were required, respectively. The mean error between manual and automatic measurement of HC was -0.21 cm corresponding to a percentage error of -0.81% with 95% limits of agreement (LOA) between -3.73% and 2.12%. For AC and FL measurements, the mean error was, respectively, 0.72 cm (percentage error, 2.40%) with LOA between -9.48% and 14.27%, and 0.21 cm (percentage error, 3.76%) with LOA between -8.38% and 15.91%., Conclusions: The automated tool identified correctly the biometric variable of interest in 99% of frozen images. The resulting measurements had a high degree of accuracy and compared well with previously published manual-to-manual agreement. The measurements exhibited bias, with the automated tool underestimating biometry; this could be overcome by further improvements in the algorithm. Nevertheless, adjustable calipers for manual correction remains a requirement. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.)