Comparison of IOL Master 700 versus Lenstar LS900 for preoperative biometric measurement and intraocular lens calculation in cataract patients with high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To compare the differences, correlations and consistency of IOL Master 700 or Lenstar LS900 in preoperative ocular biometry and the accuracy of intraocular lens(IOL)degree calculation of cataract patients with high myopia.METHODS: Retrospective study. A total of 136 cases(136 eyes)of high myopia and cataract patients who underwent phacoemulsification at the ophthalmology department of Army Medical Center of PLA from March 2021 to March 2023 were collected, with a mean age of 57.38±8.08 years. Patients were divided into 3 groups based on axial length(AL): 41 eyes in group A(26 mm≤ AL ≤28 mm), 43 eyes in group B(28 mm< AL ≤30 mm)and 52 eyes in group C(AL >30 mm). AL, mean keratometry(Km), anterior chamber depth(ACD), lens thickness(LT)and white-to-white(WTW)were preoperatively measured by two instruments, respectively. Barrett Universal II formula was used to calculate the IOL degrees of all patients, the appropriate reserved diopter was decided individually, and the prediction error(PE)and absolute error(AE)of the two instruments were compared.RESULTS:The AL and ACD of patients in the three groups measured by Lenstar LS900 were higher than the AL measurd by IOL Master 700(all P<0.05), with a difference of AL measured by the two devices: group C>group B>group A. However, there was no statistical significance in LT, Km, and WTW measured by the two instruments(all P>0.05). All biometric parameters measured by the two devices were positively correlated(all r>0.9, P<0.05), and consistent(95% LoA of all groups were narrow). There was no statistically significant difference in AE calculated by the two devices(P>0.05), but the IOL Master 700 calculated a smaller PE than Lenstar LS900(P<0.05), with lower percentage of hyperopic shift in IOL Master 700.CONCLUSION:In cataract patients with high myopia, AL measured by Lenstar LS900 is longer than that by IOL Master 700, and the differences of AL increase along with the growth of AL. Both devices have a good prediction for IOL calculation, but IOL Master 700 has less refractive error, lower percentage of hyperopic shift, and greater clinical advantages IOL Master 700.

Comparison of optical biometry and conventional acoustic biometry in the axial length measurement in silicone oil-filled eyes

Purpose: To compare the axial length (AL) obtained by A-scan biometry (PAC SCAN 300AP; Sonomed Escalon, USA) and LENSTAR-LS 900 (Haag-Streit, Koeniz, Switzerland) in silicone oil (SiO)-filled eyes. Methods: AL measurements were taken in 50 SiO-filled eyes using A-scan and LENSTAR-LS 900 before SiO removal and 1 month following SiO removal. In the subset of patients requiring intraocular lens (IOL) insertion, the predicted refraction and the refraction obtained were compared. IOL power in these patients was calculated using SRK-T formula and the AL obtained by LENSTAR. Results: In SiO-filled eyes, a significant difference was noted between the AL values obtained using the two methods (P = 0.0002). No significant difference was noted after SiO removal (P = 0.634). In the subset of patients needing IOL insertion, no significant difference (P = 0.07) was seen between target refractive error and postoperative refractive error (mean deviation from the target being 0.176 diopter). AL of an SiO-filled eye is more accurately measured using optical low coherence reflectometry (OLCR)-based biometry (LENSTAR) than with conventional acoustic biometry (A-scan). Conclusion: We conclude that LENSTAR gives more accurate biometry in an SiO-filled eye. The AL obtained after SiO removal was comparable and showed no significant difference

Parámetros biométricos oculares en candidatos a cirugía de catarata / Ocular biometric parameters in cataract surgery candidates

Introducción: Las estructuras ópticas pueden variar en su configuración y medida dependiendo de la edad, el sexo y la raza, por lo que su medición previa a la cirugía es un pilar fundamental para el cálculo correcto del lente intraocular. Caracterizar los rangos normales de estos parámetros en nuestra población suministra información importante que puede mejorar los resultados visuales tras la cirugía de catarata y alertar en aquellos casos que distan de la media de los rangos conocidos. Objetivo: Describir los parámetros biométricos oculares en pacientes candidatos a cirugía de catarata y analizar sus variaciones según la edad y el sexo. Método: Estudio observacional descriptivo, de corte transversal. Análisis retrospectivo de biometrías oculares realizadas con reflectometría óptica de baja coherencia en pacientes candidatos a cirugía de catarata. Resultados: Se evaluaron 820 ojos de 820 pacientes candidatos a cirugía de catarata, con una edad media de 68.1 ± 11.1 años, el 53.7% de sexo femenino. Los parámetros oculares promedios encontrados fueron: longitud axial (AL) 23.39 ± 1.11 mm, profundidad de cámara anterior (ACD) 3.37 ± 0.49 mm, astigmatismo corneal (AST) 1.09 ± 0.85 D, espesor corneal central (CCT) 529.43 ± 35.02 µm, poder queratométrico (K) 43.81 ± 1.64 D, queratometría plana 43.28 ± 1.69 D, queratometría curva 44.37 ± 1.74 D y distancia blanco a blanco 11.82 ± 0.52 mm. El promedio de AL y ACD fue mayor en los hombres que en las mujeres (p < 0.0001), y con el aumento de la edad el AST y el K mostraron una tendencia al incremento. Se encontró un 23.78% de astigmatismo con la regla, un 54.88% de astigmatismo contra la regla y un 21.34% de astigmatismo oblicuo. Conclusiones: El perfil de los datos biométricos evidenció diferencias significativas entre sexos y grupos de edad. Se encontró una buena correlación entre la AL, la ACD y la potencia corneal, y los promedios encontrados se corresponden bien con los de otras poblaciones de similar origen étnico.

Introduction: Optical structures can vary in their configuration and measurement depending on age, sex and race, so their measurement, prior to surgery, is a fundamental pillar for the correct calculation of the intraocular lens. Characterizing the normal ranges of these parameters in our population provides important information that can improve the visual results of cataract surgery and alert in those cases that are far from the mean of the known ranges. Objective: To describe the ocular biometric parameters in cataract surgery candidates. Method: Descriptive, cross-sectional study. Retrospective analysis of biometric parameters measured by optical low-coherence reflectometry in cataract surgery candidates. Results: The study evaluated 820 eyes of 820 cataract patients, the mean age was 68.1 ± 11.1 years, 53.7% female. Mean ocular parameters found were: axial length (AL) 23.39 ± 1.11 mm, anterior chamber depth (ACD) 3.37 ± 0.49 mm, corneal astigmatism (AST) 1.09 ± 0.85 D, central corneal thickness (CCT) 529.43 ± 35.02 µm, keratometry (K) 43.81 ± 1.64 D, flat keratometry (K1) 43.28 ± 1.69 D, steep keratometry (K2) 44.37 ± 1.74 D and white-to-white distance (WTW) 11.82 ± 0.52 mm. Mean AL and ACD were significantly longer in men (p < 0.0001) and with increasing age, AST and K showed an upward trend. 23.78% of astigmatism with the rule, 54.88% of astigmatism against the rule and 21.34% of oblique astigmatism were found. Conclusions: The profile of the biometric data showed significant differences between sex and age groups, a good correlation was found between axial length, chamber depth and keratometry. The averages found correspond well to those of other populations of similar ethnic origin

Comparison of ocular biometry by two kinds of optical biometers in Chinese adolescents / 眼科新进展

Objective To evaluate the repeatability and agreement of two optical biometers (Lenstar LS900 (R) and SW-9000) for ocular biometry in Chinese adolescents.Methods A prospective study was conducted which included 65 ametropic patients,with an average age of (11.45 ± 2.67) years (age ranging from 8 to 18 years).The ocular biometry for right eyeball was performed with Lenstar LS900 (R) and SW-9000 respectively,followed by evaluation of the repeatability of the two biometers using one-way analysis of variance,and the agreement of the two instruments using the Bland-Altman plot.Results The repeatability of parameters measured by Lenstar LS900 (R),including axial length (AL),K value in the flattest meridian (K1),K value in the steepest meridian (K2),central corneal thickness (CCT),anterior depth (AD),lens thickness (LT),pupil diameter (PD),was well,and all intraclass correlation coefficient (ICC) ＞ 0.9;the repeatability of white to white (WTW) was inferior to other parameters,but it was still ＞0.88.The repeatability of AL,K1,K2,CCT measured by SW-9000 was good,with their ICC ＞ 0.9,but the repeatability of other parameters was poor.The parameters with good repeatability including AL,K1,K2,CCT measured by SW-9000 and Lenstar LS900 (R) were compared respectively,and the results showed that AL and CCT examined by SW-9000 were slightly longer than those measured by Lenstar LS900 (R),and the difference was statistically significant (all P ＜ 0.05).However,there was no significant difference about K1,K2 (all P＞0.05).Moreover,the AL,K1,K2 and CCT measured by the two instruments had close linear correlation (all r ＞0.97,all P ＜0.01).The BlandAltman plot showed that 95％ LoA (limits of agreement) of AL was (-0.057 to 0.133) mm,K1 was (-0.456 to 0.369) D,K2 was (-0.388 to 0.549) D and CCT was (-3.483 to 8.016) μm.Conclusion Biometric parameters including AL,K1,K2,CCT measured by Lenstar LS900 (R) and SW-9000 have good repeatability in the adolescents aged 8-18 years and they are highly correlated;meanwhile,the agreement of AL,K1,K2,CCT measured by SW-9000 with Lenstar LS900 (R) is acceptable in clinical practices.

Reproducibility of VERION Digital Guidance System and its comparability with iTrace, Lenstar LS900 and manual keratometer in measuring keratometry and astigmatism / 眼科新进展

Objective To analyze the reproducibility of keratometry and astigmatism measured by the VERION Digital Guidance System and the comparability of VERION with iTrace,Lenstar LS900 and manual keratometer.Methods The keratometry of 62 cataract patients were measured using four different devices.The steep keratometry (Ks),flat keratometry (Kf),astigmatic magnitude,astigmatic axis,cylinder at 0-degree meridian (vector component,J0) and cylinder at 45-degree meridian (vector component,J45) from each machine were recorded and analyzed.The three repeated measurements and the results of VERION system with other three devices were compared to analyze the reproducibility and comparability of VERION system.Results Reproducibility:Intraclass correlation coefficients and Cronbach's alpha values were higher than 0.9 for Ks,Kf,astigmatic magnitude,astigmatic axis,J0 and J45 measured by the VERION system (all P ＜ 0.001).Comparability:The results of Ks and magnitude of astigmatism of VERION were larger than the iTrace (all P ＜ 0.05) in the paired-samples t test.There was no statistical difference for the rest of parameters (all P ＞ 0.05).The Bland-Altman graphs revealed the 95％ limits of agreement (LOA) of J0,J45 and the astigmatic axis between VERION and iTrace were (-0.31-0.35) D,(-0.25-0.31) D and-13.5 °-12.3 °,respectively;There was no statistical differences for all parameters except for J45 in the paired-samples t test between the VERION and Lenstar LS900 (all P ＞ 0.05).The Bland-Altman graphs revealed the 95％ LOA of J0,J45 and the astigmatic axis were (-0.25-0.31)D,(-0.27-0.36) D and-13.5°-11.0°,respectively;There were statistical differences for the results of Kf and magnitude of astigmatism between the VERION and manual keratometer (all P ＜ 0.05).The Bland-Altman graphs revealed the 95％ LOA of J0,J45 and the astigmatic axis between VERION and manual keratometer were (-0.38-0.35) D,(-0.41-0.42) D,-12.6°-16.4°,respectively.Conclusion The VERION system is a reliable system for the measurement of keratometry and astigmatism.The keratometry and astigmatic magnitude of the VERION system have a good agreement with the iTrace,Lenstar LS900 and manual keratometer.However,the astigmatic axis measurements are significantly different among the four devices.

A Comparison of Axial Length, Keratometry, and Measured White-to-white Using Different Devices

PURPOSE: To compare the accuracy and clinical usefulness of various devices by measuring axial length, keratometry, and white-to-white. METHODS: In 64 eyes of 56 cataract patients, axial length was measured using Galilei™, Lenstar®, and A-scans, and keratometry was measured using Galilei™, Lenstar®, and ARK. In 86 eyes of 74 cataract patients, white-to-white was measured using Galilei™ and Lenstar®. RESULTS: The average axial length measurements using Galilei™, Lenstar®, and A-scans were significantly correlated (p < 0.001), but without a statistically significant difference (p = 0.611). The 95% agreement range was the smallest at 0.22 mm for the Lenstar® and A-scans. The average mean K using Galilei™, Lenstar®, and ARK were significantly correlated (p < 0.001), but without a statistically significant difference (p = 0.657). The 95% agreement range was relatively small at 1.83 D for Lenstar® and ARK. The average white-to-white using Galilei™ and Lenstar® were significantly correlated (p < 0.001), with a statistically significant difference (p = 0.011). The 95% agreement range was 2.20 mm. CONCLUSIONS: Axial length, keratometry, and white-to-white measured by different devices were highly correlated and were not statistically different; however, agreement was low between measurements. It is therefore important to consider these findings when using them equally.

Comparision of Corneal Refractive Power Measured with Opitcal Low-coherence Reflectometry, Autokeratometer, and Topography in Children

PURPOSE: To compare the keratometry obtained from optical low-coherence reflectometry (Lenstar LS900®), autokeratometer (KR-8100®), and topography (Medmont E300®) in children. METHODS: A retrospective study was performed in 316 eyes of 160 subjects. Subjects were divided into 3 groups according to age. Group 1 was younger than 10 years, group 2 was older than 10 years and younger than 18 years, and group 3 was older than 18 years. Subjects were tested using the Lenstar LS900®, KR-8100®, and Medmont E300®. Comparisons were made for steep K, flat K, mean K, and astigmatism among three groups. Agreement among the 3 devices was examined using the Bland-Altman method. RESULTS: The keratometry measured by Medmont E300® was highest, followed by that of Lenstar LS900® and KR-8100® in all 3 groups. Almost all keratometry was significantly different among the 3 devices except for the flat K measured by LS900® and KR-8100® in all 3 groups and flat K measured by KR-8100® and Medmont E300® in Group 3 (p < 0.05). With regard to mean K, the agreement between Lenstar LS900® and KR-8100® was better than that between the other two pairs in both Groups 1 and 2, while agreement between Lenstar LS900® and Medmont E300® was better in Group 3. The agreement between KR-8100® and Medmont E300® was worse than that between the other two pairs in Groups 1 and 3, while the agreement between Lenstar LS900® and Medmont E300® was worse in Group 2. CONCLUSIONS: There were significant differences in keratometry among the 3 devices in all 3 groups. In children, Medmont E300® showed relatively less agreement compared with the other two devices. In adults, however, the agreement between 2 devices showed variable results. Consideration of the keratometry measurement from Lenstar LS900®, KR-8100®, and Medmont E300® might be helpful to estimate accurate corneal keratometry in children.

Comparison of Anterior Chamber Depth and Central Corneal Thickness Measured Using Different Devices

PURPOSE: To compare the accuracy and clinical usefulness of different devices by measuring anterior chamber depth (ACD) with three devices and central corneal thickness (CCT) with four devices. METHODS: In 180 eyes of 90 healthy subjects, ACD was measured using A-scan, Lenstar LS900®, Pentacam®, and CCT was measured using ultrasound pachymetry (USP), Lenstar LS900®, Pentacam®, and anterior segment optical coherence tomography (OCT). RESULTS: The average ACT measurements using Lenstar LS900®, A-scan, and Pentacam® were 3.27 ± 0.35 mm, 3.26 ± 0.36 mm, and 3.25 ± 0.36 mm, respectively. The measurements were significantly correlated (p < 0.001) but without statistically significant difference (p = 0.017). The Bland-Altman plots showed a low degree of agreement. The average CCT measurements using Pentacam®, USP, Lenstar LS900®, and OCT were 553.31 ± 25.23 µm, 547.26 ± 23.83 µm, 541.38 ± 24.49 µm, and 531.40 ± 22.33 µm, respectively. The measurements were significantly correlated (p < 0.001) and statistically significantly different (p < 0.05). The Bland-Altman plots showed a low degree of agreement. CONCLUSIONS: ACD and CCT measured using different devices were highly correlated, but the ACD measurements were not statistically different; however, the CCT measurements were statistically different, and agreement was low between both measurements.

Comparison of Central Corneal Thickness and Anterior Chamber Depth Measured Using Three Different Devices

PURPOSE: To compare measurements of central corneal thickness (CCT) and anterior chamber depth (ACD) obtained using Galilei(TM), Pentacam(R) (Oculus, Wetzlar, Germany) and Lenstar(R) (Haag-Streit, Koeniz, Switzerland) and analyze the measurement agreements. METHODS: CCT and ACD were measured using Galilei(TM), Pentacam(R) and Lenstar(R) in 47 eyes of 25 healthy subjects. The measurements were compared among the 3 devices. RESULTS: The average CCT measurements using Galilei(TM), Pentacam(R) and Lenstar(R) were 552.6 +/- 29.41 microm, 543.9 +/- 30.50 microm and 537.5 +/- 30.26 microm, respectively. The measurements significantly correlated with each other (r > 0.9, p 0.9, p < 0.001), but were statistically significantly different (p = 0.034). The CCT 95% limits of agreement (LoA) between Galilei(TM) and Pentacam(R), Pentacam(R) and Lenstar(R) and Lenstar(R) and Galilei(TM) were 31.95 microm, 44.76 microm and 46.57 microm, respectively and 95% ACD LoA were 0.46 mm, 0.32 mm and 0.28 mm, respectively. CONCLUSIONS: CCT and ACD measured using the 3 devices were highly correlated with each other but the measurements were statistically different. Therefore, the measurements were not interchangeable and these differences should be considered in clinical use.

Comparison of Ocular Biometry Using Low-Coherence Reflectometry with Other Devices for Intraocular Lens Power Calculation

PURPOSE: To compare axial length (AL) and keratometry (K) using optical low-coherence reflectometry (OLCR, Lenstar LS900(R), Haag-Streit, Bern, Switzerland) with current ocular biometry devices and evaluate the accuracy of intraocular lens (IOL) power calculation. METHODS: In this prospective, comparative observational study of eyes with cataracts, AL and K were measured using an OLCR device (Lenstar LS900(R), Haag-Streit), partial coherence interferometry (PCI, IOL Master(R), Carl Zeiss, Jena, Germany), A-scan (Eyecubed) and automated keratometry (KR-7100, Topcon, Tokyo, Japan). IOL power calculation was performed using the Sanders-Retzlaff-Kraff (SRK/T) formula. The IOL prediction error (PE) was calculated by subtracting the predicted IOL power from the postoperative (PO) IOL power (PO 4 weeks, PO 12 weeks). RESULTS: A total of 50 eyes of 39 patients with cataracts (mean age 67.12 +/- 8.51 years) were evaluated in this study. AL and K were not significantly different between the OLCR device and other devices (analysis of variance [ANOVA], p = 0.946, 0.062, respectively). The mean PE in IOL power calculation was -0.22 +/- 0.50D with the OLCR device, 0.08 +/- 0.45D with the PCI device and -0.01 +/- 0.48D with A-scan and automated keratometry (ANOVA, p = 0.006). The highest percentage of eyes with PE smaller than +/- 0.5D was IOL Master(R) followed by Eyecubed and then Lenstar LS900(R). The mean absolute PE was not statistically significant among the 3 devices (ANOVA, p = 0.684). CONCLUSIONS: Ocular biometry measurements were comparable between the OLCR device and the PCI ultrasound device. However, the IOL power prediction showed significant differences among the 3 devices. Therefore, the differences in application of these devices should be considered.

Comparison of corneal astigmatisms measured by Lenstar LS900 and auto-refractor / 天津医药

Objective To compare the differences of corneal keratometry and corneal astigmatism measured by Len?star LS900 and KR-1 auto-refractor of age-related cataract. Methods Seventy-six patients with cataract (76 eyes) were in?cluded in this study. Flat keratometry (K1), steep keratometry (K2), mean keratometry (Km) and astigmatism were measured before operation by Lenstar LS900 and KR-1 auto-refractor. The parameters of astigmatism were transformed into J0 and J45 by Fourier vector transform, and which was compared. Results Values of K1, K2, Km, J0 and J45 were (43.960±1.440) D, (44.901±1.319)D, (44.430±1.336)D, 0.043±0.402 and 0.017±0.425 measured by Lenstar LS900, respectively, and which measured by KR-1 auto-refractor were (44.007 ± 1.400)D, (44.859 ± 1.338)D, (44.433 ± 1.330)D,-0.058 ± 0.322 and 0.031 ± 0.419, respectively. There was no statistical difference between these values measured by two instruments ( P>0.05). The Bland-Altman plots showed that two devices had coincident results for corneal parameters. Conclusion Lenstar LS900 and KR-1 auto-refractor can be applied in the measurement of corneal astigmatism of age-related cataract before surgery.

Comparison of anterior segment parameters with Lenstar 900 and Sirius system / 国际眼科杂志(Guoji Yanke Zazhi)

AlM: To compare the anterior segment measurements derived from optical low coherence reflectometer ( Lenstar LS900 ) and combined Scheimpflug - Placido disk topographer ( Sirius) . METHODS: ln this study, we enrolled healthy myopic subjects 54 ( 87 eyes ) . The central corneal thickness (CCT), anterior chamber depth (ACD), flat keratometry ( FK) readings , steep keratometry ( SK ) readings and white to white ( WTW ) were measured by LS900 and Sirius. Evaluation and analysis were performed using paired t tests, the Pearson correlation, and Bland-Altman analyses. RESULTS: The CCT and ACD measurements were significantly lower whereas FK, SK and WTW measurements were higher with LS900 (P CONCLUSlON: Anterior segment parameters evaluated with LS900 and Sirius systemare correlated well and achieve good agreement. However, there are significantly statistical differences which may be caused by the different measurement modes, so they may not be interchangeable use under certain clinical circumstances.

Comparison on eye biometry of Lenstar 900, A-scan ultrasound and keratometer in patients with cataract / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the differences among Lenstar 900, A-scan ultrasound and keratometer in measurement of axial length ( AL ) , anterior chamber depth ( ACD ) and corneal curvature ( K1 , K2 , Km ) , and evaluate the consistency of the instruments, with the purpose providing references for the clinical application of Lenstar 900. METHODS: In this study we picked up 36 patients ( 50 eyes ) underwent cataract surgery, and lens nucleus hardness were under level IV. Before the operation, AL, ACD and K1 , K2 , Km were measured by Lenstar 900, A-scan ultrasound and keratometer respectively. The differences between the results were compared by the paired t-test. The correlation of the results was analyzed by Pearson correlation analysis, and the consistency was measured by Bland-Ahamn method. RESULTS: The mean AL and ACD values measured by Lenstar 900 and A-scan ultrasound had no significantly statistic differences (P>0. 05). The K1, K2, Km measured by Lenstar 900 and keratometer were not significantly statistical different (P>0. 05). The results measured by these three instruments had close linearity correlation ( r>0.9, P CONCLUSION:The preoperatively biometric result of Lenstar 900, A - scan ultrasound and keratometer in patients with cataract are all reliable, and they can be substituted by each other. However, Lenstar 900 can not only measure AL, ACD and corneal curvature at the same time, but also cornal thickness, lens thickness, white to white, pupil size, optical axis eccentricity, retinal thickness and so on. It has a number of advantages such as non-touching, convenient and efficient, and can be recommended to use widely.

Comparison of Anterior Segment Measurements Using Scanning-Slit Topography and Optical Low-Coherence Reflectometry (OLCR) Biometry

PURPOSE: To compare the results of anterior segment biometry including white-to-white (WTW) between scanning-slit topography (ORBscan IIz(R), Bausch & Lomb), optical low-coherence reflectometry (OLCR) biometry (Lenstar(R), Haag-Streit), and Castroviejo calipers. METHODS: Measurements on 72 eyes of 36 patients that underwent refractive surgery were measured using ORBscan(R), Lenstar(R), and calipers and compared. Ocular biometry parameters used in this study included the WTW, central corneal thickness, anterior chamber depth (ACD), keratometry, and pupil size. RESULTS: The WTW measurements using ORBscan(R) and calipers (11.57 +/- 0.35 mm and 11.58 +/- 0.34 mm, respectively) were statistically similar. However, the measurement using Lenstar(R) (12.05 +/- 0.40 mm) was significantly greater than with the other methods (p < 0.001). Central corneal thickness and keratometry measurements using ORBscan(R) were greater than when using Lenstar(R) (p = 0.01 for both). ACD and pupil size measurement using Lenstar(R) were greater than when using ORBscan(R) (p < 0.001 for both). CONCLUSIONS: Because WTW and ACD measurements using Lenstar(R) were greater than when using ORBscan(R) and calipers, unexpected high-vaulting may be observed due to the selection of a larger-sized posterior chamber phakic intraocular lens. Therefore, the differences in measurements obtained when using these methods should be considered.

Comparison of Anterior Segment Measurements Using Scanning-Slit Topography and Optical Low-Coherence Reflectometry (OLCR) Biometry

PURPOSE: To compare the results of anterior segment biometry including white-to-white (WTW) between scanning-slit topography (ORBscan IIz(R), Bausch & Lomb), optical low-coherence reflectometry (OLCR) biometry (Lenstar(R), Haag-Streit), and Castroviejo calipers. METHODS: Measurements on 72 eyes of 36 patients that underwent refractive surgery were measured using ORBscan(R), Lenstar(R), and calipers and compared. Ocular biometry parameters used in this study included the WTW, central corneal thickness, anterior chamber depth (ACD), keratometry, and pupil size. RESULTS: The WTW measurements using ORBscan(R) and calipers (11.57 +/- 0.35 mm and 11.58 +/- 0.34 mm, respectively) were statistically similar. However, the measurement using Lenstar(R) (12.05 +/- 0.40 mm) was significantly greater than with the other methods (p < 0.001). Central corneal thickness and keratometry measurements using ORBscan(R) were greater than when using Lenstar(R) (p = 0.01 for both). ACD and pupil size measurement using Lenstar(R) were greater than when using ORBscan(R) (p < 0.001 for both). CONCLUSIONS: Because WTW and ACD measurements using Lenstar(R) were greater than when using ORBscan(R) and calipers, unexpected high-vaulting may be observed due to the selection of a larger-sized posterior chamber phakic intraocular lens. Therefore, the differences in measurements obtained when using these methods should be considered.

Comparación de los valores del espesor corneal central según los equipos Lenstar, Galilei y Pentacam / Comparative study of the central corneal thickness measurements taken by Lenstar, Gallilei and Pentacam equipment

Objetivo: Comparar valores del espesor corneal central obtenidos mediante la paquimetría con el sistema de interferometria de coherencia parcial (Lenstar) con los sistemas Scheimpflug (Pentacam; Oculus) y Galilei (Ziemer, Suiza). Métodos: Se realizó un estudio prospectivo, comparativo en 120 ojos de 60 pacientes. Para la comparación se tomaron varias mediciones recomendadas por los fabricantes para probar la eficacia del equipo con el nuevo biómetro Lenstar LS 900 (Haag Streit AG) y con los equipos Pentacam y Galilei. La comparación de los valores se realizó mediante el análisis de regresión lineal y correlación de Pearson. Resultados: El análisis reveló que existe una alta correspondencia en los valores del espesor corneal central entre Lenstar y los topógrafos Galilei y Pentacam. Conclusiones: Existe una alta correspondencia entre los valores del espesor corneal central obtenidos por los equipos Lenstar, Pentacam y Galilei. Por esto el equipo Lenstar es útil en la cirugía de catarata y la cirugía refractiva.

Objective: To compare the central corneal thickness measurements taken by pachimetry with the partial coherence interferometry, Lenstar and with Scheimpflug systems (Pentacam; Oculus) and Galilei (Ziemer, Switzerland). Methods: Comparative and prospective study of 120 eyes from 60 patients. Several recommended measurements were taken with the optical biometers LenstarLS 900 (Haag Streit AG) and with Pentacam y Galilei topographers. The results were evaluated using the linear regresión analysis and Pearson´s correlation. Results: There is high correlation among the central corneal thickness measurements taken by the Lenstar equipment and topographers Pentacam and Galilei. Conclusion: The new biometer LENSTAR provided results that correlated very well with those of the Pentacam and Galilei systems. The Lenstar is a precise device that will be helpful for any cataract or refractive surgery.

Comparison of Ocular Biometry and Postoperative Refraction in Cataract Patients Between Lenstar(R) and IOL Master(R)

PURPOSE: To compare axial length, anterior chamber depth, and keratometric measurements of an optical low-coherence reflectometry device with those of other ocular biometry devices and evaluate the accuracy of predicting postoperative refraction. METHODS: A total of 32 eyes in 32 patients who received cataract surgery were included in the present study. The axial length, anterior chamber depth, and keratometry were measured by optical low-coherence reflectometry (Lenstar LS900(R)), partial coherence interferometry (IOL master(R)), and ultrasound. The SRK/T formula was used to calculate IOL power, and predictive error that subtracts predictive refraction from postoperative refraction was compared among ocular biometry devices. RESULTS: Axial length, anterior chamber depth, and keratometry had a strong correlation and demonstrated no statistically significant differences between Lenstar LS900(R) and other devices. The Bland-Altman plots showed a high degree of agreement between Lenstar LS900(R) and other devices. The mean absolute prediction errors in Lenstar LS900(R) and IOL master(R) were not significantly different. CONCLUSIONS: The ocular biometric measurements and prediction of postoperative refraction using Lenstar LS900(R) were as accurate as IOL master(R) and ultrasound.

Comparison of the biometric measuring outcomes between Lenstar and A-scan ultrasound biometry or keratometer in cataract patient / 中华实验眼科杂志

Background The accuracy of biometric measurement is critical for precise diagnoses and prognosis evaluation of ocular diseases.Objective The present study was to evaluate the differences of Lenstar with A-scan ultrasound biometry or keratometer in ocular bio-measurement.Methods Written informed consent was obtained from each subject before examination.Total 43 eyes of 40 age-related cataract patients were enrolled in this study.Axial length,corneal curvature (K1,K2,Km) and intraocular lens (IOL) power were measured with Lenstar,A-scan ultrasound biometry and keratometer,separately.The differences of measuring outcomes were compared between these two methods according to a paired samples t test,and the agreement analysis of measuring outcomes between Lenstar and A-scan ultrasound biometry or keratometer was performed by Blant-Altman plots.Results Thirty-five eyes finished the clinical bio-measurement.The axial length was (23.341 ± 1.208) mm and (23.268 ±1.157)mm based on Lenstar method and A-scan ultrasound biometry method,respectively,with a insignificant difference between them(t =0.260,P=0.796).No significant differences were found in the K1,K2 and Km values between Lenstar and keratometer methods (t =0.526,P =0.601 ; t =0.927,P =0.357 ; t =0.213,P =0.832).The IOL power was (20.371 ±2.827) D and (20.729 ± 2.672) D,respectively in Lenstar method and keratometer method,without statistically significant difference between them (t =0.543,P =0.589).Bland-Altamn agreement analysis showed that the dots of 11％ (4/35),0％ (0/100),9％(3/35),9％ (3/35),6％ (2/35) were out of 95％ confidence limit,and the absolute values of maximal difference value between Lenstar and A-scan ultrasound biometry or keratometer methods was 0.39 mm,1.31 D,1.30 D,0.77 D and 1.00 D in ocular axial length,K1,K2 and Km values and IOL power,respectively.Conclusions As a new bio-measuring method,Lenstar can offer multiple biometric parameters by single procedure.However,an inconsistent measuring outcome is seen between Lenstar and Ascan ultrasound biometry or keratometer.So whether Lenstar can replace A-scan ultrasound biometry or keratometer still need further large simple clinical trail.

Comparison of Ocular Biometry Measured by Ultrasound and Two Kinds of Partial Coherence Interferometers

PURPOSE: To evaluate the reproducibility and repeatibility of biometry in cataractous eyes, pseudophakic eyes and eyes having undergone refractive surgery. The OcuScan(R)RxP, LENSTAR(R) and IOL Master(R) instruments were compared, as were. The accuracies of the refractive results after cataract surgery. METHODS: The biometries of 45 cataractous eyes, 31 pseudophakic eyes, and 32 eyes having undergone refractive surgery were measured by two practitioners using OcuScan(R)RxP, LENSTAR(R) and IOL Master(R) instruments. The paired t-test was used to compare the reproducibilities in the three groups. RESULTS: There were no differences in axial length among the groups when using any of the instruments. There was no significant difference in the repeatibility regardless of the instrument used, although. In the cataractous eyes, pseudophakic eyes and eyes with refractive surgery, OcuScan(R)RxP showed the highest repeatability. However, we knew that all three instruments were excellent in the repeatability because the difference was less than 1.5%. The Prediction error of the instruments with regard to refractive results could not be determined after cataract surgery. In some patients with severe cataract, measurement was impossible for both the LENSTAR(R) and IOL Master(R) instruments. CONCLUSIONS: In all groups, OcuScan(R)RxP, LENSTAR(R) and IOL Master(R) showed no significant differences with regard to reproducibility or prediction of refractive power after surgery. Among three groups, the repeatability was rather high in the existing ultrasound method than in the partial coherence interferometers. In some patients with severe cataract, measurement was impossible for both the LENSTAR(R) and IOL Master(R) instruments.

Evaluación del equipo de interferometia óptica de coherencia parcial Lenstar en la biometría ocular / Evaluation of Lenstar partial coherente optical interferometry device in the ocular biometry

OBJETIVOS: Comparar y evaluar la biometría ocular con el nuevo equipo de interferometría óptica de coherencia parcial (Lenstar) con el equipo de interferometría óptica de baja coherencia IOL Master y también con los sistemas topográficos Galilei y Pentacam. MÉTODOS: Se realizó un estudio descriptivo, transversal, en 120 ojos de 60 pacientes. Para el cálculo del lente intraocular se tomaron mediciones con un nuevo biómetro Lenstar LS 900 (Haag Streit AG) y con el IOL Master V.5 (Carl Zeiss Meditec AG). Se compararon mediante el análisis de regresión lineal y correlación de Pearson. También se compararon las medidas con las obtenidas por los equipos topógrafos Galilei y Pentacam. RESULTADOS: Existe una alta correspondencia en los valores biómetricos de longitud axial, queratometría y profundidad de la cámara anterior entre los equipos Lenstar e IOL Master. También se encontró una buena correspondencia entre las medidas de profundidad de cámara posterior y queratometría entre Lenstar y los topógrafos Galilei y Pentacam. CONCLUSIONES: El nuevo biómetro Lenstar, provee resultados que se correlacionan muy bien con aquellos obtenidos con los equipos IOL Master, Pentacam y Galilei. El equipo Lenstar es un equipo preciso que brinda información adicional por lo que es útil en la cirugía de catarata y la cirugía refractiva

OBJECTIVES: To compare and to evaluate the ocular biometry taken by a new optical partial coherence interferometry device (Lenstar),the low coherence optical interferometry equipment (ILO Master) and the topographic systems Pentacam y Galilei. METHODS: A descriptive cross-sectional study was conducted in 120 eyes from 60 patients. For the IOL calculation, the necessary measurements were taken with the new optical biometer Lenstar LS 900 (Haig Streit AG) and with the IOL Master V5 (Carl Zeiss Meditec AG). The results were evaluated using the linear regression analysis and Pearson´s correlation. The measures were then compared to those taken by topographic devices Galilei and Pentacam. RESULTS: There existed high correlation in biometric measurements of axial length, keratometry and anterior chamber depth between the Lenstar and the IOL Master. Good correlation was also found for the Keratometry and anterior chamber depth between the Lenstar and the topographs Pentacam and Galilei. CONCLUSION: The new biometer LENSTAR provided results that correlated very well with those of the IOL Master, Pentacam and Galilei systems. Lenstar is a precise device offering additional features that will be helpful for any cataract or refractive surgery