Biometry and intraocular power calculation using a swept-source optical coherence tomography: A repeatability and agreement study

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

Enseñar física a través del teatro / Physics teaching through theater

RESUMEN El problema de investigación en este trabajo es articular el arte del teatro, su pasión y su estética, a la formación científica, para pensar, sentir y disfrutar el mundo. El objetivo de este trabajo fue determinar cómo valoran los estudiantes de educación media y docentes en formación, el uso de la obra "Galileo Galilei", para la enseñanza de la Física clásica. Esta investigación es interpretativa, con un diseño cualitativo de casos múltiples. Para la recolección y análisis de información, se usaron las técnicas de grupo focal y de análisis del discurso. Los resultados mostraron un aprendizaje más dinámico y divertido, cambio en las concepciones sobre la naturaleza de las ciencias y mejora en las relaciones sociales.

ABSTRACT The research problem in this work is to articulate the art of the theater with his passion and aesthetic, to a scientific formation, for thinking, feeling and enjoying the world. The objective of this research was to determine how the students of middle education and preservice teacher, value the use of the "Galileo Galilei" play, to teach classical physics. This research is interpretive, and qualitative design, with multiple cases. For the collection and analysis of information, the focus group and discourse analysis techniques were used. The results showed a more dynamic and fun learning, change in the conceptions about the nature of the sciences, and improve in social relations.

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.

Astigmatic Correlation between the Automated Refractometry and Dual Scheimpflug Analyzer in Pseudophakic Eyes

PURPOSE: To examine the relationship between the refractive astigmatism by automated refractometry and the corneal astigmatism by a dual Scheimpflug analyzer in pseudophakic eyes. METHODS: Prospectively, 75 patients (100 eyes) were enrolled in the present study. Refractive astigmatism was obtained by automated refraction. Corneal astigmatism was obtained using automated keratometry (ARK-530A®) and dual Scheimpflug scanning analysis (Galilei G4®). All refractive values were converted to the power vector components J0 and J45 for comparison and regression analysis of refractive versus corneal astigmatism. Bland-Altman plots were created to estimate the agreement between measurements. RESULTS: The average astigmatism from each measurement was -1.11 ± 1.44 D (refractive astigmatism from automated refraction), -0.77 ± 1.06 D (corneal astigmatism from automated keratometry), -0.93 ± 1.02 D (simulated K from Galilei G4®), and -1.11 ± 1.48 D (total corneal power from Galilei G4®). Refractive J0 and keratometric J0 were significantly correlated (r = 0.557, p ≤ 0.001), as well as the corresponding J45 values (r = 0.655, p = 0.025). Refractive astigmatism and total corneal power components were also significantly correlated (J0: r = 0.618, p ≤ 0.001; J45: r = 0.608, p = 0.04). In the Bland-Altman plots, keratometric J0 and total corneal power J0 showed the best agreement. CONCLUSIONS: The accuracy of measurements for corneal refraction and astigmatism in pseudophakic eyes is higher using the dual Scheimpflug analyzer, especially for total corneal power. This value of astigmatism can take into account the refractive astigmatism of pseudophakic eyes and can be used in evaluating postoperative corneal astigmatism.

Repeatability of corneal power measurements by Galilei Ⅱ dual Scheimpflug analyzer in post-LASIK eyes / 中华实验眼科杂志

Background The assessment of total corneal power is essential to both the prediction of intraocular lens power before cataract surgery and the diagnosis of corneal ectasia.Objective This study was to access the repeatability of corneal power measurements in post-laser assisted in-situ keratomileusis (LASIK) eyes with GalileiⅡ dual Scheimpflug analyzer.Methods In this cross-sectional study,68 eyes of 36 subjects who received LASIK surgery more than 3 months in Eye Hospital of Wenzhou Medical University were recruited from July to September in 2011.The mean preoperative spherical equivalent diopter was (-4.95±2.08) D in the subjects with the diopter range from-1.75 D to-10.00 D.The parameters of corneal power were measured by Galilei Ⅱ dual Scheimpflug analyzer,including SimK,Ka,Kp,KG and Kray.Three-time consecutive measurements were completed in every examined eye to obtain the data of SimK,Ka,Kp,KG and Kray,respectively.The coefficient of variation (CV),standard deviation (SD),Cronbach α coefficient and intra-class correlation coefficient (ICC) were calculated to evaluate the repeatability.Concordance between the different measurements was assessed using Bland-Altman agreement analysis.This study followed the Helsinki Declaration,all subjects signed informed consent.Results The CVs of three-time measured SimK,Ka,Kp,KG and Kray were 0.24％,0.28％,-0.37％,0.31％ and 0.32％,respectively,and the Cronbach α values were ＞0.9 and the ICCs were ＞0.982.The Bland-Altman analysis between different measurements showed that the maximum 95％ limits of agreement (LoA) were 0.37 D for SimK,0.46 D for Ka,0.09 D for Kp,0.45 D for KG and 0.49 D for Kray,respectively.Conclusions The Galilei Ⅱ dual Scheimpflug analyzer performed high repeatability and concordance on corneal power measurements in post-LASIK eyes.The differences between measuring results are clinically acceptable.

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 and Postoperative Refraction in Cataract Patients between Galilei-G6(R) and IOL Master(R)

PURPOSE: To compare the axial lengths, anterior chamber depths, and keratometric measurements and to predict postoperative refractions of Dual Scheimpflug analyzer Galilei G6(R) and intra ocular lens (IOL) Master(R). METHODS: A total of 50 eyes in 50 patients who received cataract surgery were included in the present study. The axial length, anterior chamber depth, and keratometry were measured using 2 types of partial coherence interferometries (Galilei G6(R) and IOL Master(R)). The SRK/T formula was used to calculate IOL power and the predictive error which subtracts predictive refraction from postoperative refraction was compared between the ocular biometry devices. RESULTS: Axial lengths were 23.36 +/- 0.80 mm and 23.36 +/- 0.90 mm measured by Galilei G6(R) and IOL Master(R), respectively. Axial length measured by Galilei G6(R) was not statistically significant compared with IOL Master(R) (p = 0.321). The anterior chamber depth and keratometry were 3.22 +/- 0.35 mm and 44.29 +/- 1.40 D measured by Galilei G6(R) and 3.11 +/- 0.46 mm and 44.39 +/- 1.41 D measured by IOL Master(R), respectively. The differences of anterior chamber depth and keratometry between the 2 devices were statistically significant (p < 0.001 and p = 0.028, respectively). The mean absolute prediction errors were 0.45 +/- 0.37 D and 0.49 +/- 0.39 D in Galilei G6(R) and IOL Master(R), respectively and was not statistically significantly different (p = 0.423). CONCLUSIONS: The ocular biometric measurements and prediction of postoperative refraction using Galilei G6(R) were as accurate as with IOL Master(R).

Comparison of Corneal Higher-Order Aberrations Measured with Two Instruments Using Scheimpflug Camera System

PURPOSE: To compare the corneal higher-order aberrations (HOAs) of normal young subjects using Galilei(TM) G4 (Zeimer, Port, Switzerland) and Pentacam(R) (Oculus Inc., Wetzlar, Germany). METHODS: Corneal HOAs were measured using Galilei(TM) G4 and Pentacam(R) in 41 healthy individuals (41 eyes). Intraclass correlation coefficients (ICCs) were obtained to evaluate the repeatability of the 2 devices. Differences in HOAs between the 2 instruments were analyzed with a paired t-test and correlations evaluated. RESULTS: All ICCs measured using Galilei(TM) G4 and Pentacam(R) showed more than moderate repeatability (>0.81) except trefoil, tetrafoil, 4th and 5th HOAs. When comparing the measurements obtained with Galilei(TM) G4 and Pentacam(R), total HOAs, spherical aberration (SA), secondary astigmatism and 5th total HOAs were statistically significantly different between the 2 device (all p < or = 0.001). In addition, Galilei(TM) G4 and Pentacam(R) showed discrepancy among all corneal HOAs items. Although the total corneal HOAs and the SA were significantly correlated, other HOA measurements generally exhibited a low correlation. CONCLUSIONS: Corneal HOAs obtained by the 2 instruments cannot be used interchangeably due to their differences and discrepancy although corneal HOAs measured using Galilei(TM) G4 and Pentacam(R) showed relatively high repeatability.

Diagnóstico del queratocono subclínico por topografía de elevación / Diagnosis of the subclinical keratoconus through elevation topography

OBJETIVO: definir parámetros más eficaces de la topografía de elevación para la detección del queratocono subclínico. MÉTODOs: se estudiaron con topografía Galilei las córneas de 15 pacientes con diagnóstico clínico de queratocono (grupo 1: n = 23 ojos), de 12 pacientes con queratocono subclínico diagnosticados por topografía de elevación (grupo 2: n = 18) y un grupo control de 13 pacientes miopes distribuidos por sexo, edad y equivalente esférico refractivo (grupo 3: n = 25). Se analizaron los siguientes parámetros: localización del ápex, elevación de las caras anterior y posterior de la córnea, paquimetría mínima y profundidad de cámara anterior. RESULTADOS: la ubicación más frecuente del ápex fue en el sector inferotemporal (52,1 %). El promedio de máxima elevación de la cara anterior fue 40,83 ± 17,75 mm en el grupo 1 y de 16,89 ± 8,22 mm en el grupo 2, donde ambos fueron significativamente diferentes al grupo control (p < 0,02). El promedio de la máxima elevación de la cara posterior fue 73,35 ± 17,73 mm en el grupo 1 y 41,22 ± 9,94 mm en el grupo 2. Ambos resultados fueron significativamente diferentes al grupo control (p < 0,00). El mínimo espesor y la profundidad de cámara anterior también mostraron diferencias estadísticamente significativas entre los grupos estudiados. CONCLUSIONES: los parámetros de elevación de cara anterior, posterior, paquimetría y profundidad de cámara anterior, medidos en la topografía de elevación con Galilei, difieren significativamente entre individuos normales y con queratocono clínico y subclínico.

OBJECTIVE: to define the most effective parameters of corneal elevation topography for subclinical keratoconus screening. METHODS: Galilei topography system-based study included corneas from 15 patients with clinical diagnosis of keratoconus (group 1, n = 23 eyes), from 12 patients with subclinical keratoconus (group 2, n = 18 eyes) and a control group of 13 myopic subjects paired in gender, age and refractive spherical equivalent (group 3, n = 25). The following parameters were analyzed: location of the apex, anterior and posterior corneal elevation, minimal pachyimetry and anterior chamber depth. RESULTS: the most frequent location of the apex was at the inferotemporal sector (52 %). Mean anterior maximum elevation was 40,83 ± 17,75 mm in group 1 and 16,89 ± 8,22 mm in group 2; these results were significantly different from the control group (p < 0,02). Mean posterior maximum elevation was 73,35 ± 17,73 mm in group 1 and 41,22 ± 9,94 mm in group 2, both showing a statistically significant difference from that of the control group (p < 0,00). Minimal corneal thickness and anterior chamber depth also showed statistically significant differences among the three groups. CONCLUSIONS: statistically significant differences were found in anterior and posterior elevation, minimal corneal thickness and anterior chamber depth parameters, as measured by the Galilei system, between the normal myopic subjects, and those with clinical and subclinical keratoconus.

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.

Corneal Thickness Measured by Dual Scheimpflug, Anterior Segment Optical Coherence Tomography, and Ultrasound Pachymetry

PURPOSE: To compare central corneal thickness (CCT) as measured by dual rotating Scheimpflug camera (Galilei), anterior segment optical coherence tomography (AS-OCT), and ultrasound pachymetry (USP). METHODS: The measurements of CCT using a dual rotating Scheimpflug camera, AS-OCT, and USP in 40 eyes of 20 healthy subjects were compared. RESULTS: The average measurements of CCT by dual rotating Scheimpflug camera, AS-OCT, and USP were 538.10 +/- 31.36 microm, 536.20 +/- 31.21 microm, and 541.93 +/- 34.93 microm, respectively. The CCT measurement by USP was statistically significantly thicker than by the dual rotating Scheimpflug camera and AS-OCT (p = 0.017, p = 0.001, respectively). There was no significant difference between the dual rotating Scheimpflug camera and AS-OCT (p = 0.054). A significant linear correlation was observed between the dual rotating Scheimpflug camera, the AS-OCT, and the USP (r > 0.900, p < 0.001). CONCLUSIONS: The results of the 3 methods have significant correlation with each other, but the measurement by USP was significantly thicker than the dual rotating Scheimpflug camera and AS-OCT. Therefore, CCT should be interpreted in the context of the instrument used.

Comparison and Repeatability of Anterior Segment Parameters Obtained by Galilei and Slit-lamp Optical Coherence Tomography

PURPOSE: To evaluate the repeatability and comparability of anterior chamber depth (ACD) and central corneal thickness (CCT) measurements obtained by Galilei dual Scheimpflug analyzer (Ziemer, Port, Switzerland) and slit-lamp optical coherence tomography (SL-OCT; Heidelberg Engineering, Dossenheim, Germany). METHODS: ACD and CCT were measured by Galilei and SL-OCT in 68 eyes of 68 healthy young subjects. Each measurement was performed 3 times by a single examiner, and the repeatability of 3 consecutive measurements was analyzed. ACD and CCT measurements were compared between the 2 devices. RESULTS: Both Galilei and SL-OCT showed high repeatability (ICCs > or = 0.994) for ACD and CCT measurements. The mean ACD and CCT measured by Galilei were greater than SL-OCT measurements by 0.11 +/- 0.09 mm and 14.01 +/- 7.38 microm, respectively. The 95% limit of agreement values for ACD and CCT measurements were 0.36 mm, 27.66 microm, respectively, and were highly correlated (correlation coefficients > or = 0.89, p < 0.001). CONCLUSIONS: Although the repeatability of each device was high, ACD and CCT obtained by Galilei and SL-OCT were significantly different. These differences should be considered when interpreting ACD and CCT measurements obtained by the 2 devices.

Measurement of White-to-White Diameter and Anterior Chamber Depth by Dual Scheimpflug Camera

PURPOSE: To estimate the horizontal and vertical white-to-white diameters (WTW) and anterior chamber depths (ACD) with a dual Scheimpflug camera (GALILEI(TM), Ziemer, Switzerland) and to compare the estimates measured by a measuring caliper and ultrasound biomicroscopy (UBM PlusTM, Paradigm Inc., Utah, USA) in normal subjects. METHODS: Forty-four eyes of 23 subjects were evaluated. Corneal diameter as measured by GALILEI was directly compared with the white-to-white diameter (WTW) measured by a caliper and the correlation with ciliary sulcus diameter (STS) by UBM was evaluated. The anterior chamber depth (ACD) as measured by GALILEI(TM) was compared with the estimates measured by UBM. RESULTS: The horizontal and vertical diameters of WTW by GALILEI were not significantly different from the measurements taken by calipers (p>0.05, p>0.05, respectively), and there were no correlations between the measurements (r=-0.074, p>0.05 at 180degrees r=0.297, p>0.05 at 90degrees, respectively). The estimates by GALILEI did not correlate with those measured with UBM (r=-0.006, p>0.05 at 180degrees r=-0.222, p>0.05 at 90degrees, respectively). However, the mean ACD by GALILEI was deeper than thatby UBM (p<0.01), and the measurements correlated strongly with each other (r=0.760; p<0.01). CONCLUSIONS: The mean WTW measured by GALILEI was not significantly different from the measurements taken by calipers and the measurements did not correlate with each other. There was also no correlation with the measurementsby GALILEI and UBM. ACD by GALILEI was measured to be deeper those that by UBM.

Central Corneal Thickness Measured by Four Different Methods in Normal and Post-Femtosecond Laser-Assisted LASIK Eyes

PURPOSE: To compare corneal pachymetry assessment using four measurement methods in normal and post-femtosecond laserassisted LASIK eyes. METHODS: Central corneal thickness was measured sequentially using Orbscan II, Pentacam, Galilei and ultrasonic pachymetry in 30 normal, non-surgical eyes (Group I), 30 eyes one to six months after femtosecond laser-assisted LASIK (Group II), and 30 eyes six months or longer after femtosecond laser-assisted LASIK (Group III). RESULTS: In Group I, corneal thickness measurements were similar for all four methods (P=0.202, one way ANOVA). In Groups II and III, corneal thickness measurements were significantly different (P=0.000, respectively, one way ANOVA). Compared to the Pentacam, Galilei and ultrasonic pachymetry, Orbscan significantly underestimated the corneal thicknesses in Groups II and III (P<0.005, respectively, one way ANOVA). CONCLUSIONS: Central corneal thicknesses of normal eyes were similar for all four measurements, therefore corneal thickness measurements before refractive surgery using all four measurements is suitable. However measurements obtained with the Orbscan II were thinner than those obtained with the Pentacam, Galilei or ultrasonic pachymetry in post femtosecond laserassisted LASIK eyes. Further studies are needed to determine which instrument is more accurate in measuring central corneal thickness before and after refractive surgery.

The Intra and Inter-Examiner Repeatability of Corneal Parameters Obtained by GALILEI(TM) in Normal Subjects

PURPOSE: To verify the intra-examiner and inter-examiner repeatability of corneal parameters obtained by GALILEI(TM). METHODS: Corneal parameters were measured by GALILEI in 44 eyes of 28 healthy subjects. One examiner took the measurements twice and intra-examiner repeatability was evaluated. Another examiner measured the corneal parameters once again and inter-examiner repeatability was evaluated. RESULTS: Intra-examiner and inter-examiner repeatability were high for corneal parameters including average SimK, flat SimK, steep SimK, average posterior corneal keratometry, flat posterior corneal keratometry, steep posterior corneal keratometry, central corneal thickness, total corneal volume, and average pupil diameter but low for limbus-to-limbus diameter (nasal-temporal and superior-inferior). CONCLUSIONS: Anterior and posterior corneal parameters of GALILEI showed good intra-examiner and inter-examiner repeatability. However, limbus-to-limbus diameter showed poor intra-examiner and inter-examiner repeatability. GALILEI can be useful in clinical applications with special consideration when measuring the limbus-to-limbus diameter.

William Harvey y los inicios de la ciencia médica moderna / William Harvey and the beginnings of modern medical science

El Renacimiento no hizo más que preparar el terreno para el surgir de la ciencia médica moderna. Ésta nació, de hecho, en la época posrenacentista y comenzó a afianzarse a mediados del siglo XVII por obra de físicos, fisiólogos y biólogos, que eran discípulos directos o indirectos de Galileo. El descubrimiento de la circulación de la sangre por Harvey se considera hoy día como el único adelanto en fisiología de principios del siglo XVII, comparable a los avances contemporáneos de las ciencias físicas. La historia de esta hazaña podría escribirse fácilmente desde el punto de vista del avance progresivo del conocimiento. En sus investigaciones, Harvey se refería a experimentos auténticos, no imaginados. y aducía irrefutables argumentos cuantitativos. Se ha afirmado con justicia que su descubrimiento de la circulación sanguínea fue la primera explicación adecuada de un proceso orgánico y el punto de partida del camino hacia la fisiología experimental. Sin embargo, la segunda monografía del sabio de Folkestone acerca de la generación de los animales, publicada en 1651, mientras que en algunos pasajes da la impresión de corresponder al razonamiento científico moderno, muestra en otros pasajes aseveraciones confusas, vagas y caprichosas, rescoldo de la era precientífica de la que el autor no había salido por completo. Puede aseverarse, por tanto, que la ciencia médica moderna no surgió de manera subitánea y global, sino que se estructuró gradualmente desde mediados del siglo XVII siguiendo la senda trazada por William Harvey a la luz del pensamiento de Galileo.

Modern medical science was born in the post Renaissance age and began to consolidate towards the middle of the XVII century thanks to physicists, physiologists, and biologists, most of whom were direct or indirect pupils, of Galilei. The discovery of blood circulation by Harvey is now considered the only progress in physiology at the beginning of the XVII century, comparable to the current advances seen in physical sciences. The history of this achievement could be written from the view point of the progressive advance in knowledge. In his experiments, Harvey referred to the authentic, not the imaginary experiments, and put forward irrefutable quantitative arguments. We can therefore claim that his discovery of blood circulation was the first proper explanation of an organic process and the starting point leading to experimental physiology. Nevertheless, the second monograph of the english researcher, dealing with the generation of animals, published in 1651, has some passages that correspond to modern scientific reasoning yet in others he includes confused, vague and capricious assertions compatible with the prescientific era that the author was not able to escape completely. In conclusion, it seems justified to assert that modern medical science did not all rise suddenly, but was gradually structured starting from the middle of the XVII century following the path traced by William Harvey in light of Galilei's thought.