Infrared Illumination and Subcutaneous Venous Network: Can it be of Help for the Study of CEAP C1 Limbs?

OBJECTIVE: The subcutaneous venous network (SVN) is difficult to see with the naked eye. Near infrared illumination (NIr-I) claims to improve this. The aims of this observational study were to investigate whether there are differences between the different methods; to quantify the length and diameter of SVNs; and to confirm if they differ between C0A and C1 CEAP limbs. METHODS: In total, 4 796 images, half of them from the visible spectrum (VS) and the other half from the nearninfrared spectrum (NIrS), belonging to 109 females (C0A: n = 50; C1 CEAP: n = 59) were used to establish the morphological characteristics of the SVN by visual analysis. With Photoshop CS4, SVN diameters and lengths were obtained by digital analysis of 3 052 images, once the images of whole extremities were excluded. RESULTS: On NIr-I, the diameters, trajectories, and colouration of SVNs of C1 limbs appeared more irregular than SVNs of C0A limbs. Compared with the VS images, NIr-I allowed visualisation of a greater length of the SVN in both groups (p < .010). This capacity varied from 2.6 ± 0.9 times (C1) to 16.2 ± 11.9 (C0A). While the SVN length seen in the VS images from C1 limbs was greater than observed in C0A limbs (p < .001), differences between NIr-I images only existed in the lateral part of the lower leg (p = .016). With NIr-I, the median diameter of the C1 CEAP SVN veins was 5.8 mm (interquartile range [IQR] 4.3-7.5 mm), while the median diameter in C0A SVN limbs was 2.6 mm (IQR 2.0-3.6 mm) (p < .001). CONCLUSION: The NIr-I reveals the characteristics of the SVN better than the naked eye. Further studies are required to determine the significance of the changes in the SVN in C0A and C1 limbs, and the factors causing them.

Segmentation of elastic fibres in images of vessel wall sections stained with Weigert's resorcin-fuchsin.

BACKGROUND AND OBJECTIVE: The elastic fibres are an essential component of the extracellular matrix in blood vessel walls that allows a long-range of deformability and passive recoil without energy input. The quantitative determination of elastic fibres will provide information on the state of the vascular wall and to determine the role and behaviour of this key structural element in different physiological and pathological vascular processes. METHODS: We present a segmentation method to identify and quantify elastic fibres based on a local threshold technique and some morphological characteristics measured on the segmented objects that facilitate the discrimination between elastic fibres and other image components. The morphological characteristics analysed are the thickness and the length of an object. RESULTS: The segmentation method was evaluated using an image database of vein sections stained with Weigert's resorcin-fuchsin. The performance results are based on a ground truth generated manually resulting in values of sensitivity greater than 80% with the exception in two samples, and specificity values above 90% for all samples. Medical specialists carried out a visual evaluation where the observations indicate a general agreement on the segmentation results' visual quality, and the consistency between the methodology proposed and the subjective observation of the doctors for the evaluation of pathological changes in vessel wall. CONCLUSIONS: The proposed methodology provides more objective measurements than the qualitative methods traditionally used in the histological analysis, with a significant potential for this method to be used as a diagnostic aid for many other vascular pathological conditions and in similar tissues such as skin and mucous membranes.

Quantification and Statistical Analysis Methods for Vessel Wall Components from Stained Images with Masson's Trichrome.

PURPOSE: To develop a digital image processing method to quantify structural components (smooth muscle fibers and extracellular matrix) in the vessel wall stained with Masson's trichrome, and a statistical method suitable for small sample sizes to analyze the results previously obtained. METHODS: The quantification method comprises two stages. The pre-processing stage improves tissue image appearance and the vessel wall area is delimited. In the feature extraction stage, the vessel wall components are segmented by grouping pixels with a similar color. The area of each component is calculated by normalizing the number of pixels of each group by the vessel wall area. Statistical analyses are implemented by permutation tests, based on resampling without replacement from the set of the observed data to obtain a sampling distribution of an estimator. The implementation can be parallelized on a multicore machine to reduce execution time. RESULTS: The methods have been tested on 48 vessel wall samples of the internal saphenous vein stained with Masson's trichrome. The results show that the segmented areas are consistent with the perception of a team of doctors and demonstrate good correlation between the expert judgments and the measured parameters for evaluating vessel wall changes. CONCLUSION: The proposed methodology offers a powerful tool to quantify some components of the vessel wall. It is more objective, sensitive and accurate than the biochemical and qualitative methods traditionally used. The permutation tests are suitable statistical techniques to analyze the numerical measurements obtained when the underlying assumptions of the other statistical techniques are not met.

Efectos del entrenamiento de natación sobre la asimetría corporal en adolescentes / Effects of swimming training on body asymmetry in adolescents

El objetivo fue realizar una evaluación antropométrica de ambos hemisferios corporales en nadadores adolescentes. La muestra estuvo formada por 83 nadadores (52 hombres y 31 mujeres) con una edad media de 15,21±1,90 años. Sus valores antropométricos fueron analizados en función de las siguientes variables: edad, género, años de entrenamiento, estilo de nado (simultáneo o alternativo), lado dominante, lado no dominante, lado de respiración, peso y estatura, con el fin de determinar la existencia o no de diferencias en la composición de cada lado del cuerpo del nadador. Para evaluar la composición corporal se utilizaron: pliegues (tricipital, subescapular, bicipital, cresta iliaca, supraespinal, abdominal, anterior del muslo y pierna), longitudes (brazo, antebrazo, mano, muslo, pie y pierna), perímetros (brazo relajado, brazo flexionado, antebrazo, muñeca, muslo, pierna y tobillo) y diámetros (muñeca, mano, pie, bimaleolar, húmero y fémur). También fueron determinados otros valores como: la masa grasa, muscular, residual, ósea y sus porcentajes, así como el sumatorio de pliegues y el cálculo del somatotipo. Los datos obtenidos mostraron que no existen diferencias estadísticamente significativas entre las medidas tomadas a cada lado corporal de los nadadores, incluso cuando éstas fueron analizadas desde las variables, años de entrenamiento y estilo de nado. La práctica continua e intensa de la natación durante las etapas de crecimiento, no provoca asimetrías corporales entre ambos lados de los nadadores, incluso con técnica de nado alternativo, corroborando que la natación es un deporte de trabajo muscular completo y de composición corporal equilibrada.

The purpose of this study was to conduct an anthropometric assessment of both sides of the body in adolescent swimmers. The sample comprised 83 swimmers (52 males and 31 females) with an average age of 15.21±1.90 years. Their anthropometric values were studied in relation to the variables of age, sex, years of training, swimming stroke (simultaneous or alternating), dominant side, non-dominant side, breathing side, weight and height to determine whether any differences existed in the composition of each side of the swimmers bodies. Body composition was assessed using skinfolds (tricipital, subscapular, bicipital, iliac crest, supraspinal, abdominal, anterior thigh and anterior lower leg), lengths (upper arm, forearm, hand, thigh, lower leg and foot), perimeters (relaxed arm, flexed arm, forearm, wrist, thigh, lower leg and ankle) and diameters (wrist, hand, foot, malleolus, humerus and femur). Other values determined were fat mass, muscle mass, residual mass and bone mass (including percentages), sum of skinfolds and calculation of somatotype. The data obtained showed no statistically significant differences between the measures taken on each side of the swimmers bodies, even when they were analysed using the variables of years of training and swimming stroke. Continuous, intensive swimming during the growth stages does not cause body asymmetry in swimmers, even when the swimming stroke is alternating, thus supporting the thesis that swimming is a sport that works all muscles and provides a balanced body composition.