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AIM: To observe the changes in the Chang-Warning chord(CW chord)before and after cataract surgery using the IOL Master 700 and predict the CW chord using an artificial intelligence prediction model and preoperative measurement data.METHODS: The analysis was conducted on the preoperative and postoperative IOL Master 700 measurements of 304 cataract patients. This included astigmatism vector value, average keratometry, axial length, anterior chamber depth, lens thickness, corneal central thickness, white-to-white, the position of the Purkinje reflex I image relative to the corneal center and pupil center, and the CW chord. A prediction model based on the SVR algorithm and the BP neural network algorithm was established to predict the postoperative CW chord using the preoperative CW chord and ocular biological parameters.RESULTS: The X component of the CW chord showed a slight shift in the temporal direction in both the left and right eyes after cataract surgery, while the Y component changed little. The SVR model, using the preoperative CW chord and other preoperative biometric parameters as input data, was able to predict the X and Y components of the CW chord more accurately than the BP neural network.CONCLUSION: The CW chord can be directly measured with a coaxial fixation light using various biometers, corneal topographers, or tomographers. The use of the SVR algorithm can accurately predict the postoperative CW chord before cataract surgery.
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AIM: To compare the difference and consistency of corneal refractive power and astigmatism measured by CASIA2 and IOL Master 700 in patients with age-related cataract.METHODS: Retrospective study. A total of 153 patients(232 eyes)with age-related cataract admitted to Daping hospital from November to December 2021 were selected. The flat keratometry(Kf), steep keratometry(Ks), mean keratometry(Km), degree and axis of astigmatism(vector representation J0 and J45)of the anterior, posterior surfaces together with the total cornea from cataract patients were measured by CASIA2 and IOL Master 700, respectively. The difference, correlation and consistency of the two instruments were analyzed.RESULTS:There was no significant difference in J45 values of posterior corneal surface measured by CASIA2 and IOL Master 700(-0.006±0.038D vs. -0.005±0.044D, P>0.05), but there were significant differences in other parameters(all P<0.05). All parameters measured by the two instruments were significantly positive correlated(all r/rs>0.7, P<0.001); Bland-Altman analysis showed that the refractive power and astigmatism of the anterior cornea surface measured by the two facilities were in good consistency, while the refractive power of the posterior surface and the whole cornea showed poor consistency.CONCLUSION: CASIA2 and IOL Master 700 showed little differences and good consistency in the refractive power and astigmatism of the anterior, posterior and total corneal surface in cataract patients, which seems interchangeable. However, the refractive power of the posterior surface and the whole cornea has significant differences and poor consistency, which should not be interchange casually.
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Purpose: To evaluate the repeatability of biometry and intraocular lens (IOL) power using Galilei G6 and to determine the agreement of its measurements with those of IOL Master 700 and IOL Master 500. Methods: Hundred mature cataract eyes were examined twice with Galilei G6 and the results were compared with those of other two devices. Axial length (AL), minimum (K1), maximum (K2), and mean keratometry, anterior chamber depth (ACD), white-to-white (WTW) diameter, lens thickness (LT), and the calculated IOL power were the studied parameters. The correlation coefficient, within-subject standard deviation (Sw), Bland–Altman method, and 95% limits of agreement (LoA) were used for statistical analysis. Results: The intraclass correlation coefficient (ICC) was above 0.9 for all indices, and the LoA ranged from a minimum of 0.08 mm for AL to a maximum of 0.50 D for K1. Sw also ranged between a minimum of 0.02 for AL, ACD, and WTW and a maximum of 0.13 for K1. In the Galilei G6–IOL Master 700 pair, the narrowest and widest LoA were calculated for AL (0.07 mm) and K2 (0.49 D), respectively. In the Galilei G6–IOL Master 500 pair, the narrowest and widest widths of LoA were calculated for AL (0.17 mm) and K2 (0.92 D), respectively. In the first pair, the LoA of IOL power (0.57 D) were the best for Haigis formula and in the second pair, the best agreement (LoA: 0.35 D) was observed for Holladay-1. Conclusion: Galilei G6 provided repeatable biometric measurements. The agreement between biometry and IOL power calculation was better in the Galilei G6–IOL Master 700 pair compared to the Galilei G6–IOL Master 500
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AIM:To evaluate the accuracy of A-ultrasound combined with corneal topography measurement in clinical application by analyzing the ocular-related biometric parameters and refractive error and comparing with those of IOL Master 700 in cataract patients. METHODS: A prospective study. Clinical data were collected from 113 patients(122 eyes)who underwent phacoemulsification in the First Affiliated Hospital of Soochow University from July 2020 to July 2021. The axial length(AL), anterior chamber depth(ACD), lens thickness(LT)and corneal curvature(Km)were measured respectively by IOL Master 700 and A-ultrasound combined with corneal topography measurement and the 3mo after the surgery of the refractive error was analyzed.RESULTS: There were differences in AL(24.09±1.65, 23.81±1.62mm), ACD(3.11±0.42, 2.97±0.43mm)and Km(44.12±1.59, 44.06±1.54D)measured by IOL Master 700 and A-ultrasound combined with corneal topography(P<0.05), while there was no difference in LT(4.34±0.46, 4.30±0.59mm)(P>0.05). The postoperative mean absolute refractive error(MAE)of intraocular lens(IOL)diopter calculation formulas with different measurement methods was significantly different(P<0.001). The Barrett Universal II formula MAE of the IOL Master 700 measuring instrument was different from the Holladay I, Haigis and SRK/T formulas(P<0.01), at the same time, compared with the A-ultrasound combined with corneal topography calculation formula SRK/T and Barrett Universal II formula, they were also different(P<0.01). However, there was no difference among the Holladay Ⅰ, Haigis, SRK/T formula MAE which come from the IOL Master 700 measuring instrument and the A-ultrasound combined with corneal topography calculation formula SRK/T formula(P>0.05). In addition, the Barrett Universal II formula of the IOL Master 700 measuring instrument has the smallest median absolute refractive error(MedAE)(0.260D), and the A-ultrasound combined with corneal topography calculation formula Barrett Universal II formula MedAE is the largest(0.765D).CONCLUSION: The values of AL, ACD and Km measured by A-ultrasound combined with corneal topography were smaller than those of IOL Master 700. When the SRK/T formula was used to calculate the IOL diopter, the results of the two group were similar. However, when using the Barrett Universal Ⅱ formula, the refractive error of the A-ultrasound combined with corneal topography group was large, resulting in hyperopia drift.
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@#AIM: To investigate the difference and consistency among iTrace, IOL Master 700 and Pentacam HR in measuring corneal astigmatism before cataract surgery.<p>METHODS: Across-sectional study. From May 2020 to May 2021, a total of 149 cataract patients(181 eyes)were collected in our hospital. Presurgery, steep keratometry(Ks), flat keratometry(Kf), mean keratometry(Km), astigmatism magnitude(Cyl), and steep astigmatic axis values measured by the three instruments of the iTrace, IOL Master 700 and the Pentacam HR. The difference and consistency of the measurement indexes of the three instruments were analyzed.<p>RESULTS: Statistical differences existed in Ks, Kf, Km among the three instruments(<i>F</i>=4.912, 3.514, 4.873, all <i>P</i><0.05)and there was no difference in Cyl and Axis(<i>F</i>=0.523, 0.128, all <i>P</i>>0.05). Bland-Altman analysis showed the outcomes revealed that the Ks and Kf measured by iTrace and the other two instruments have poor consistency, and the consistency of Cyl and Axis was good. But the difference of Axis is not clinically acceptable. There were no statistically differences between the iTrace and the other two devices among the low astigmatism(50 eyes), moderate astigmatism(34 eyes)and high astigmatism(18 eyes)groups(all <i>P</i>>0.05). <p>CONCLUSION: In the preoperative measurement of cataract patients except for the good consistency of astigmatism, the iTrace, IOL Master 700 and Pentacam HR showed different Ks and Kf, and the Axis difference exceeded the clinically acceptable range, especially in the highly astigmatism group. The measurement of corneal astigmatism before cataract surgery should be evaluated by multiple measurement methods and make comprehensive planning for the surgical plan.
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Objetivo: Comparar las mediciones biométricas realizadas con el IOL Master 700 y el Pentacam AXL en pacientes miopes con cirugía fotoablativa previa. Métodos: Se realizó un estudio transversal en 103 ojos de 103 pacientes miopes con cirugía fotoablativa previa, atendidos en el período de enero 2019 a enero 2020, en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer". Las variables estudiadas fueron: edad, sexo, equivalente esférico y características biométricas posoperatorias (longitud axial, profundidad de la cámara anterior y queratometrías), así como su relación, aportadas automáticamente por el IOL master 700 y el pentacam AXL para evitar los factores dependientes del operador, tres meses después de la cirugía. El análisis estadístico se realizó con la prueba t para datos pareados, utilizando una significación del 95 por ciento. Resultados: La edad promedio fue de 25,72 ± 4,26 años. Se analizaron 53 ojos derechos y 50 izquierdos, todos tratados con láser de superficie. El equivalente esférico medio fue de -0,06 ± 0,34 dioptrías y el tiempo entre la cirugía y los exámenes fue de 6,32 ± 3,56 meses. No hubo diferencia estadísticamente significativa (p > 0,05) entre la longitud axial y la profundidad de la cámara anterior; mientras que sí la hubo (p < 0,01) con las queratometrías obtenidas con el IOL Master 700, en comparación con los del pentacam AXL. Conclusión: En pacientes miopes con cirugía fotoablativa previa, el IOL Master 700 y el pentacam AXL proveen mediciones biométricas similares, como la longitud axial y la profundidad de la cámara anterior, no así con la queratometría, la cual es diferente(AU)
Objective: Compare the biometric measurements taken with IOL Master 700 and Pentacam AXL in myopic patients with previous photoablative surgery. Methods: A cross-sectional study was conducted of 103 eyes of 103 myopic patients undergoing photoablative surgery at Ramón Pando Ferrer Cuban Institute of Ophthalmology from January 2019 to January 2020. The variables analyzed were age, sex, spherical equivalent and preoperative biometric characteristics (axial length, anterior chamber depth and keratometries) and the relationship to one another, automatically supplied by IOL Master 700 and Pentacam AXL to avoid operator-dependent factors. The analysis was performed three months after surgery. Statistical analysis was based on the paired Student's t-test with a significance level of 95 percent. Results: Mean age was 25.72 ± 4.26 years. Fifty-three right eyes and 50 left eyes were studied, all of them treated with surface laser. Mean spherical equivalent was -0.06 ± 0.34 diopters; the time elapsed between surgery and the tests was 6.32 ± 3.56 months. No statistically significant differences (p > 0.05) were found between axial length and anterior chamber depth, but statistically significant differences (p < 0.01) were observed between the keratometries obtained with IOL Master 700 and Pentacam AXL. Conclusion: IOL Master 700 and Pentacam AXL provide similar biometric measurements for axial length and anterior chamber depth in myopic patients with previous photoablative surgery, but keratometric measurements are different(AU)
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Humans , Adult , Data Interpretation, Statistical , Corneal Pachymetry/methods , Lasers , Myopia/etiology , Cross-Sectional StudiesABSTRACT
Objetivo: Comparar las mediciones biométricas realizadas con el IOL Master 500 y el Pentacam AXL. Métodos: Se realizó un estudio transversal en 99 ojos de 99 pacientes miopes con criterio de cirugía fotoablativa, atendidos en el período de enero del año 2019 a enero de 2020, en el Servicio de Cirugía Refractiva del Instituto Cubano de Oftalmología "Ramón Pando Ferrer". Las variables estudiadas fueron edad, sexo, equivalente esférico y características biométricas preoperatorias (longitud axial, profundidad de la cámara anterior y queratometrías), así como su relación, aportadas automáticamente por el IOL Master 500 y el Pentacam AXL para evitar los factores dependientes del operador. El análisis estadístico se realizó con la Prueba t para datos pareados, utilizando una significación del 95 por ciento. Una diferencia con un valor de p < 0,05 fue considerado estadísticamente significativo. Resultados: El 60,61 por ciento de los pacientes eran de sexo femenino y el 39,39 por ciento del masculino, con una edad promedio de 25,67 ± 4,30 años. Se analizaron 51 ojos derechos y 48 izquierdos. El equivalente esférico medio fue de -3,30 ± 1,53 dioptrías. No hubo diferencia estadísticamente significativa entre los valores biométricos (longitud axial, profundidad de la cámara anterior y queratometrías) obtenidos con el IOL Master 500, en comparación con los del Pentacam-AXL (p > 0,05). Conclusión: Las mediciones biométricas (longitud axial, profundidad de la cámara anterior y queratometrías) obtenidas con el IOL Master 500 y el Pentacam-AXL son similares(AU)
Objective: Compare biometric measurements taken with IOL Master 500 and Pentacam AXL. Methods: A cross-sectional study was conducted of 99 eyes of 99 myopic patients with indication of photoablative surgery attending the Refractive Surgery Service at Ramón Pando Ferrer Cuban Institute of Ophthalmology from January 2019 to January 2020. The variables analyzed were age, sex, spherical equivalent and preoperative biometric characteristics (axial length, anterior chamber depth and keratometries) and the relationship to one another, automatically supplied by IOL Master 500 and Pentacam AXL to avoid operator-dependent factors. Statistical analysis was based on the paired T-test with a significance level of 95%. A difference with a p-value < 0.05 was considered to be statistically significant. Results: Of the patients studied, 60.61 percent were female and 39.39 percent were male; mean age was 25.67± 4.30 years. A total 51 right eyes and 48 left eyes were analyzed. Mean spherical equivalent was -3.30 ± 1.53 diopters. No statistically significant difference was found between the biometric values (axial length, anterior chamber depth and keratometries) obtained with IOL Master 500 versus Pentacam AXL (p > 0.05). Conclusion: Similar biometric measurements (axial length, anterior chamber depth and keratometries) are obtained with IOL Master 500 and Pentacam AXL(AU)
Subject(s)
Humans , Male , Female , Adult , Biometry/methods , Refractive Surgical Procedures/methods , Anterior Chamber/diagnostic imaging , Cross-Sectional StudiesABSTRACT
@#AIM: To compare the differences of corneal curvature and astigmatism measured by Pentacam, IOL Master and iTrace of cataract patients.<p>METHODS:In this prospective clinical trial,68 cataract patients(82 eyes)received treatment at the ophthalmology department of our hospital. In the treatment process, used the IOL Master, Pentacam and iTrace to measure the patient's corneal curvature(K1, K2, Km)and astigmatism(J0, J45). The difference, correlation and consistence among three instruments were analysed. <p>RESULTS: Differences analysis showed that in the measurement of K1, K2, Km, there was no difference among Pentacam, IOL Master and iTrace(<i>P</i>>0.05). Pearson correlation analysis showed that K1, K2, Km were highly correlated among three instruments(|<i>r</i>|>0.5, <i>P</i><0.01). J0, J45 were moderately correlated between IOL Master and Pentacam, so as IOL Master and iTrace(0.3<|<i>r</i>|<0.5, <i>P</i><0.01). J0, J45 were weakly correlated between Pentacam and iTrace(0.1<|<i>r</i>|<0.3, <i>P</i><0.05). The Bland-Altman showed that the corneal curvature and astigmatism vectors examined by these three devices had non-comparable results.<p>CONCLUSION: K1, K2, Km, J0, J45 were correlated among the three devices, but the three devices all cannot directly interchanged, targeted selection is required for the measuring the corneal curvature and astigmatism by these three different instruments in the actual clinical process.
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@#AIM: To compare the consistency of IOL Master 700 with IOL Master 500 and A-mode ultrasound for biological measurements, and evaluate the measurements of IOL Master 700 in preoperative examinations of cataract patients. <p>METHODS:In this prospective study, a total of 52 patients(100 eyes)diagnosed as age-related cataract were selected at the Nanjing Medical University Eye Hospital. All the patients were examined in turn by IOL Master 700, IOL Master 500 and A-mode ultrasound. Measurements by these three instruments were compared for axial length(AL), corneal curvature(Km), central anterior chamber depth(ACD), white-to-white(W-W)and pupil diameter(P). The results were analyzed by one-way ANOVA, Pearson correlation and Bland-Altman. <p>RESULTS: The detection rates of AL and ACD with IOL Master 700, IOL Master 500 and A-mode ultrasound were 98%, 87%, 99% and 100%, 99%, 99%; respectively. The detection of Km with IOL Master 700 and IOL Master 500 were 100%, 99%. The detection of W-W and P were both 99%. Among them, 24 eyes had high myopia, posterior scleral grape swelling and axial length ≥26mm. The detection of AL with IOL Master 700, IOL Master 500 and A-mode ultrasound were 96%, 79%, 96%. There was a significant difference in AL and ACD between three instruments(<i>F</i>=11.58, <i>P</i>=0.03; <i>F</i>=12.46, <i>P</i>=0.02). There were no significant differences in Km, W-W and P parameters among three instruments(all <i>P</i>>0.05). The average difference between three instruments for AL measurement: IOL Master 700 and IOL Master 500 was 0.05±0.12mm, IOL Master 700 and A-mode ultrasound was 0.16±0.14mm; The average difference between three instruments for AL measurement in axial length≥26mm: IOL Master 700 and IOL Master 500 was 0.17±0.16mm, IOL Master 700 and A-mode ultrasound was 0.55±0.22mm. The Pearson's correlation analysis showed that there was a high correlation between the measured results of each equipment. The consistency of AL results using Bland-Altman analysis showed there was good consistency in the range of 95% consistency.<p>CONCLUSION: There was high consistency in ocular biological measurements between three instruments in cataract eyes. However, the detection rate of IOL Master 700 in AL was higher than that of IOL Master 500, and the accuracy of the IOL Master 700 measurement was higher in the AL measurement in high myopia with posterior staphyloma. Compared with traditional examination equipment, IOL Master 700 has better penetration and accuracy to provide more accurate measurement parameters.
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@#AIM: To evaluate the effect of pupil dilation on ocular biometry and IOL power in cataract patients with high myopia, and the difference between cataract patients with high myopia and cataract patients with normal axial length(AL).<p>METHODS:Measurements of AL, corneal curvature(K including K1 and K2), anterior chamber depth(ACD)were performed using IOLmaster in 22 cataract patients with high myopia(34 eyes)(group A)and 23 cataract patients with normal AL(39 eyes)(group B)before and after pupil dilation. SRK-T and Haigis were used to caculate pre- and post-cycloplegic IOL power.<p>RESULTS:ACD after dilation(3.84±0.58mm)significantly increased comparing with ACD before dilation(3.61±0.35mm)in group A(<i>P</i><0.01). ACD after dilation(3.30±0.70mm)also significantly increased comparing with ACD before dilation(3.13±0.63mm)in group B(<i>P</i><0.01). But the difference of pre- and post-cycloplegic ACD between the two groups was not statistically significant(<i>P</i>>0.05). Pre- and post-cycloplegic AL and K(including K1 and K2)were not significantly different in two groups(<i>P</i>>0.05). The differences between pre- and post-cycloplegic IOL power were not statistically significant using the SRK-T and Haigis formula(<i>P</i>>0.05), but the IOL power changed by over 1D after pupil dilation using the SRK-T and Haigis formula respectively in 15% and 27% of eyes in group A,in 3% and 5% in group B.<p>CONCLUSION:ACD increases after pupil dilation in cataract patients with high myopia, which is not different from cataract patients with normal AL. Pupil dilation does not affect AL, K and the IOL power(using SRK-T and Haigis)in cataract patients with high myopia. But the IOL power may change greater than in cataract patients with normal AL, so we suggest IOL power should be measured and calculated without mydriasis.
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@#In recent years, ocular biometers based on swept-source optical coherence tomography(SS-OCT)technology have emerged in ophthalmic practice. Compared with the earlier ocular biometers such as the partially coherent interference(PCI)based ones, the SS-OCT based devices have a higher signal-to-noise ratio, greater swept light wavelength, better tissue penetration, faster scanning speed, and better axial length(AL)detection rate for cataract patients. This review aims to summarize the advances of a widely used SS-OCT based device-IOL Master 700 in cataract.
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@#AIM:To compare the difference, correlation and consistency of corneal biological parameters measured by IOL Master 700 and Pentacam before cataract extraction and intraocular lens implantation in different age groups.<p>METHODS: Cross-sectional study. A total of 87 cataract patients(162 eyes)in Weifang Eye Hospital from February to September 2020 were collected, including 44 males(80 eyes)and 43 females(82 eyes)(age 61.2±9.87 years). The patients were divided into four groups: group A \〖17 cases(32 eyes), 40-50 years old\〗, group B \〖25 cases(47 eyes), 51-60 years old\〗, group C \〖28 cases(53 eyes), 61-70 years old\〗, and group D \〖17 cases(30 eyes), 71-80 years old\〗. The preoperative corneal biological parameters of cataract patients were measured by IOL Master 700 and Pentacam, and the flat axis corneal curvature(K1), steep axis corneal curvature(K2), mean corneal curvature(Km), corneal astigmatism, anterior chamber depth(ACD)and central corneal thickness(CCT)were recorded. The difference and correlation of measurement results between two kinds of biometric instruments in different age groups were analyzed. <p>RESULTS: Except for the corneal astigmatism in group C and K1 and corneal astigmatism in group D, there were significant differences between the two instruments(<i>t</i>=2.746, -2.582, 2.637, all <i>P</i><0.05), but there was no significant difference in other parameters among the four groups. Pearson correlation analysis showed that there was a good correlation between the two instruments in measuring the parameters of the four groups of patients. The results of Bland-Altman analysis showed that there was a good consistency between IOL Master 700 and Pentacam in measuring K1, K2, Km, corneal astigmatism, ACD and CCT in the four groups.<p>CONCLUSION:There was no significant difference between IOL Master 700 and Pentacam in the measurement of corneal biological parameters in cataract patients aged 40-60 years, but there was significant difference in astigmatism between 61-70 years old, astigmatism and K1 value in 71-80 years old patients. Pearson correlation analysis showed that there was a good correlation between the two instruments. Generally speaking, the consistency of the two kinds of examination equipment is good, and the corneal astigmatism and corneal curvature should be selected by comprehensive analysis of the data.
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@#AIM: To compare the differences and agreement in axial length(AL), anterior chamber depth(ACD)flat axial corneal curvature(K1)and steep axial corneal curvature(K2)measured by SW-9000 and IOL Master 500.<p>METHODS: Totally 258 eyes of 129 patients with ametropia were measured with SW-9000 and IOL Master 500. Among them, 159 eyes were low to moderate myopia(-0.75D≤ spherical equivalent <-6D)and 99 eyes were high myopia(spherical equivalent ≥-6D). Comparison between two devices were performed for AL, ACD, K1, and K2. The difference between two instruments were evaluated with a paired samples <i>t</i>-test. The correlation between the measurements was evaluated using Pearson correlation coefficients. The agreement between the devices was evaluated with Bland-Altman plots. <p>RESULTS: There was significant difference between SW-9000 and IOL Master 500 in measuring AL and ACD(all <i>P</i><0.01), but there was no significant difference between K1 and K2 in patients with low to moderate myopia. There was no significant difference in AL, ACD and K1 between SW-9000 and IOL Master 500(all <i>P</i>>0.05), but there was significant difference in K2(<i>P</i><0.05)in patients with high myopia. Pearson correlation analysis showed that AL, ACD, K1 and K2 of patients with low to moderate and high myopia were highly correlated(all <i>P</i><0.01). Bland-Altman consistency analysis showed that the two methods had good consistency in measuring AL in patients with low to moderate and high myopia, but poor consistency in measuring ACD, K1 and K2.<p>CONCLUSION: SW-9000 and IOL Master 500 have good consistency in measuring the AL of people with ametropia. The measurement of ACD and corneal curvature has poor consistency, and should be carefully selected in combination with clinical practice.
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@#AIM: To compare the measurement results of anterior chamber depth(ACD)by Pentacam, IOL Master and Contact Ultrasonic A-scan, and analyze the difference, correlation, consistency and influencing factors of the three measurement methods.<p>METHODS: In this study of 307 eyes of 250 cataract patients with preoperative, ACD estimation was done by Pentacam, IOL Master and Contact Ultrasonic A-scan. The independent sample <i>t</i>-test, Analysis of Variance(ANOVA), Pearson's correlation test and multiple linear regressions were used to analyze the results.<p>RESULTS: The mean of ACD measured by Pentacam(ACDp), IOL Master(ACDi)and A-scan(ACDa)were 2.42±0.45mm, 2.96±0.43mm, 2.58±0.36mm, the difference was statistically significant(<i>F</i>=136.694, <i>P</i><0.05). The three methods were sequentially compared in pairs, and the differences within the groups were statistically significant(<i>P</i><0.05). Pearson's correlation test was performed on the three methods in pairs, and there was a linear positive correlation within each group. When the ACDp and the central corneal thickness(CCT)were added, the sum(ACDp2)was no statistically significant compared with the ACDi(<i>P</i>=0.93). When the ACDp was less than 1.85mm(ACDi was about 2.40mm), the ACDa increases significantly and the fluctuation increases. Among the many possible influencing factors, axial length, lens thickness and age have the highest relative importance for ACD measurement.ACD was positively correlated with axial length(<i>r</i>Pentacam=0.602, <i>r</i>IOL Master=0.603, <i>r</i>A-scan=0.483), and negatively correlated with the lens thickness(<i>r</i>Pentacam= -0.382, <i>r</i>IOL Master= -0.350, <i>r</i>A-scan= -0.582), negatively correlated with age(<i>r</i>Pentacam= -0.328, <i>r</i>IOL Master= -0.414, <i>r</i>A-scan= -0.265). Three factors were included in the multiple linear regression model, and the age factor of Contact Ultrasonic A-scan was eliminated due to the low influence weight.<p>CONCLUSION: ACDp2 and ACDi may be closer to the true value of the anterior chamber depth. The Contact Ultrasonic A-scan may increase the measurement error when measuring shallow anterior chamber. Axial length, lens thickness and age have the greatest influence on ACD measurement, which are the influencing factors of Pentacam and IOL Master, but age is not the influencing factor of Contact Ultrasonic A-scan.
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Resumo Objetivo: Observar o grau de concordância das variáveis analisadas entre os dispositivos IOL Master 500 e Pentacam AXL e descrever as medias Métodos: Foram analisados 35 prontuários, totalizando 61 olhos. Todos os pacientes se submeteram à avaliação biométrica nos dois dispositivos, no período de agosto de 2018 a agosto de 2019. Os dados coletados foram: idade, sexo, profundidade da câmara anterior, comprimento axial, K1, K2, poder dióptrico da LIO e alvo refracional. Resultados: As médias das variáveis analisadas entre os dispositivos de biométricos óptica em questão tiveram diferença estatisticamente significante (p<0,05). A regressão linear não apontou influência de nenhuma das variáveis da câmara anterior na diferença de valores do poder dióptrico da LIO e do alvo refracional entre os dispositivos. Conclusão: Não houve concordância estatística entre os dispositivos para as variáveis analisadas. Portanto, deve se evitar intercambiar o uso do Pentacam AXL com o IOL Master 500.
Abstract Objective: Observe the agreement between IOL Master 500 and Pentacam AXL and describe the averages. Methods: We analyzed 35 medical records, totaling 61 eyes. All patients underwent biometric evaluation on both devices from August 2018 to August 2019. The data collected were: age, gender, anterior chamber depth, axial length, K1, K2, biometrics and IOL target. Results: The averages of the variables analyzed between the optical biometric devices in question had a statistically significant difference (p <0.05). Linear regression showed no influence of any anterior chamber variables on the difference in biometrics and target values between the devices. Conclusion: There was no statistical agreement between the devices for the analyzed variables. Therefore, the interchange of Pentacam AXL with IOL Master 500 should be avoided.
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Humans , Male , Middle Aged , Aged , Refraction, Ocular , Biometry , Axial Length, Eye , Multifocal Intraocular Lenses , InterferometryABSTRACT
RESUMEN La cirugía refractiva corneal es una buena opción para corregir el defecto refractivo de los pacientes y lograr una buena visión sin el uso de espejuelos o lentes de contacto; pero cuando no es posible, las lentes fáquicas constituyen una elección viable, especialmente en pacientes jóvenes que mantienen la acomodación. Se presenta el caso de una paciente con antecedentes de implante de lente fáquica desde hacía 13 años, quien acudió al Instituto Cubano de Oftalmología "Ramón Pando Ferrer" por disminución de la visión en ambos ojos. Se destaca la importancia en la obtención de las medidas biométricas, especialmente la longitud axil, si esta se modifica después del implante de la lente fáquica para el correcto cálculo de la lente a implantar y la obtención del buen resultado refractivo. La interferometría óptica es el mejor modo de obtener estas medidas y la longitud axil no parece modificarse con la presencia de una lente fáquica(AU)
ABSTRACT Corneal refractive surgery is a good option to correct the refractive defect and achieve good vision without the use of eyeglasses or contact lenses. When it is not possible, phakic lenses are a viable choice, particularly in young patients who maintain accommodation. A case is presented of a female patient with an antecedent of phakic lens implantation 13 years before who presents at Ramón Pando Ferrer Cuban Institute of Ophthalmology with vision reduction in both eyes. Mention should be made of the importance of obtaining biometric measurements, especially of the axial length, if it changes after phakic lens implantation, for accurate calculation of the lens to be implanted and the achievement of a good refractive result. Optical interferometry is the best way to obtain those measurements, and axial length does not seem to change with the presence of a phakic lens(AU)
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Humans , Female , Middle Aged , Cataract Extraction/methods , Refractive Surgical Procedures , Phakic Intraocular Lenses/adverse effects , Interferometry/methodsABSTRACT
@#AIM: To evaluate the repeatability and reproducibility of ocular biological measurements by a swept-source optical coherence tomography biometer IOL Master 700 in healthy eyes. <p>METHODS: A diagnostic test study of 103 healthy subjects was implemented. The right eyes were selected for measurements. Ocular biological parameters including axial length(AL), anterior chamber depth(ACD), anterior aqueous depth(AQD), keratometry readings(K), central corneal thickness(CCT), lens thickness(LT), white-to-white corneal diameter(WTW)and pupil diameter(PD)were measured using IOL Master 700 by two experienced examiners. One-way ANOVA was used to evaluate the repeatability and reproducibility for the measurements by IOL Master 700. <p>RESULTS: Regarding repeatability, the test-retest repeatability(TRT)for AL, mean K(Km), K1, K2, ACD, AQD, LT, CCT, WTW and PD obtained by the two examiners were 0.018(0.017)mm, 0.215(0.270)D, 0.325(0.334)D, 0.303(0.366)D, 0.049(0.041)mm, 0.048(0.042)mm, 0.058(0.047)mm, 6.168(5.779)μm, 0.395(0.406)mm, and 1.097(1.099)mm, respectively; the relative coefficient of variation(CoV)for all measured parameters but the PD were ≤1.219%; the intraclass correlation coefficient(ICC)for all measured parameters were ≥0.815. Regarding reproducibility, the TRT for AL, Km, K1, K2, ACD, AQD, LT, CCT, WTW, and PD obtained were 0.018 mm, 0.240 D, 0.329 D, 0.337 D, 0.048 mm, 0.048mm, 0.055mm, 6.396μm, 0.420mm, and 1.144mm, respectively; the ICC for all measured parameters was ≥0.900; the CoV for all measured parameters were ≤1.263% CoV, except for the PD(8.750%). In addition, the ICC of AL measurement for both repeatability and reproducibility were 1.000. <p>CONCLUSION: With the exception of pupil diameter, IOL Master 700 demonstrates excellent repeatability and reproducibility in ocular biological measurements for healthy eyes, especially in measurement of axial length.
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@#AIM: To study the reliability of Pentacam, OCT, Tomey OA-2000, IOL Master700, and A ultrasound pachymetry in the measurement of central corneal thickness(CCT)in myopic eyes. <p>METHODS: CCTs of 56 myopic patients(112 eyes)were measured using Pentacam, RTVue OCT, Tomey OA-2000, IOL Master 700, and A ultrasound pachymetry(NIDEK US-500). The difference, correlation, and consistency were statistically analyzed using average values taken from the five devices and the measured values produced by each device. <p>RESULTS: CCTs of 112 eyes were determined using Pentacam(530.17±25.08)μm, OCT(519.79±26.90)μm, Tomey OA-2000(521.75±26.51)μm, IOL Master 700(519.53±28.15)μm, and A ultrasound pachymetry(542.23±26.88)μm. The average value across all five devices was 526.69±26.08μm. The results of root mean square error(RMSE)and theil inequality coefficient(TIC)showed that the degree of deviation from the average of the values measured using Pentacam was the smallest. The other four devices were, from least deviation to most, Tomey OA-2000, OCT, IOL Master 700, and A ultrasound pachymetry. Typical correlation analysis showed that the correlation coefficients between the measured values of Pentacam, OCT, Tomey OA-2000, IOL Master 700, and A ultrasound pachymetry and the average values were <i>ρ</i>=0.957, <i>P</i>=0.950, <i>P</i>=0.953, <i>P</i>=0.930, and <i>ρ</i>=0.949, respectively. The results of correlation coefficient showed that Pentacam and Tomey OA-2000 had the closest correlation with the average value. The other three were, in order of closest to furthest correlation, OCT, A ultrasound pachymetry and IOL master 700. The results also showed that the measurements of Pentacam and Tomey OA-2000 were more reliable, which was consistent with the clinical situation. The results of Bland-Altman analysis showed that the five groups of measurements were closely consistent with the average values, and the CCT measurements of Pentacam and Tomey OA-2000 were the most consistent with the average values.<p>CONCLUSION: Among the five instruments, Pentacam and Tomey OA-2000 produced results that were closest to the average value in CCT measurement, with the best correlation and consistency. Their measurement methods are more objective and safer than A-scan, so they may provide better reference data for clinical practice.
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@#AIM: To compare differences and consistency of corneal curvatures in adolescent patients with low and moderate myopia measured by Pentacam, IOL Master and corneal topographic.<p>METHODS: A prospective clinical study. 291 adolescent patients(291 eyes)with low and moderate myopia who underwent orthokeratology in the Affiliated Eye Hospital of Nanjing Medical University from January 2019 to September 2019 were selected. Among them, 141 cases(141 eyes)were low myopia and 150 cases(150 eyes)were moderate myopia. Corneal curvature(K1, k2, Km)and corneal Astigmatism(J0, J45)were examined by Pentacam, IOL Master, and corneal topography. And then the difference, correlation and consistency of the measurement results of three instruments were analyzed.<p>RESULTS: Differences analysis showed that in the measurement of J45, there was no difference between Pentacam and corneal topography(<i>P</i>>0.05)in patients with low and moderate myopia; in the measurement of J0,there was no difference between Pentacam and IOL Master(<i>P</i>>0.05)in patients with low myopia; in the measurement of K2,there was no difference between Pentacam and corneal topography(<i>P</i>>0.05)in patients with low myopia; in the measurement of J0,there was no difference between Pentacam and corneal topography(<i>P</i>>0.05)in patients with moderate myopia. But there were significant differences in other measurements among three instruments(<i>P</i><0.05). Pearson correlation analysis showed that K1, K2, Km, J0, and J45 were highly correlated among three instruments(<i>r</i>=0.545-0.997, all <i>P</i><0.001). Bland-Altman consistency analysis showed that three instruments had good consistency.<p>CONCLUSION: Pentacam, IOL Master and corneal topographic have good consistency and can be used as a mutual reference before orthodontic fitting of low and moderate myopia patients. The measurement difference between Pentacam and corneal topography is the smallest among three instruments, but whether three instruments can be replaced by each other needs to be considered in combination in clinical application.
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@#AIM: To evaluate the repeatability and reproducibility of ocular biological measurements by a swept-source optical coherence tomography biometer IOL Master 700 in healthy eyes. <p>METHODS: A diagnostic test study of 103 healthy subjects was implemented. The right eyes were selected for measurements. Ocular biological parameters including axial length(AL), anterior chamber depth(ACD), anterior aqueous depth(AQD), keratometry readings(K), central corneal thickness(CCT), lens thickness(LT), white-to-white corneal diameter(WTW)and pupil diameter(PD)were measured using IOL Master 700 by two experienced examiners. One-way ANOVA was used to evaluate the repeatability and reproducibility for the measurements by IOL Master 700. <p>RESULTS: Regarding repeatability, the test-retest repeatability(TRT)for AL, mean K(Km), K1, K2, ACD, AQD, LT, CCT, WTW and PD obtained by the two examiners were 0.018(0.017)mm, 0.215(0.270)D, 0.325(0.334)D, 0.303(0.366)D, 0.049(0.041)mm, 0.048(0.042)mm, 0.058(0.047)mm, 6.168(5.779)μm, 0.395(0.406)mm, and 1.097(1.099)mm, respectively; the relative coefficient of variation(CoV)for all measured parameters but the PD were ≤1.219%; the intraclass correlation coefficient(ICC)for all measured parameters were ≥0.815. Regarding reproducibility, the TRT for AL, Km, K1, K2, ACD, AQD, LT, CCT, WTW, and PD obtained were 0.018 mm, 0.240 D, 0.329 D, 0.337 D, 0.048 mm, 0.048mm, 0.055mm, 6.396μm, 0.420mm, and 1.144mm, respectively; the ICC for all measured parameters was ≥0.900; the CoV for all measured parameters were ≤1.263% CoV, except for the PD(8.750%). In addition, the ICC of AL measurement for both repeatability and reproducibility were 1.000. <p>CONCLUSION: With the exception of pupil diameter, IOL Master 700 demonstrates excellent repeatability and reproducibility in ocular biological measurements for healthy eyes, especially in measurement of axial length.