Department of Morphology, University of Las Palmas de Gran Canaria, Edificio Ciencias de la Salud, Las Palmas de Gran Canaria, Spain; CliniVar, Clínica de Varices, Las Palmas de Gran Canaria, Spain.
IUMA Information and Communication Systems, University of Las Palmas de Gran Canaria, Edificio Electrónica y Telecomunicación, Las Palmas de Gran Canaria, Spain.
Eur J Vasc Endovasc Surg. 2020 Apr;59(4):625-634. doi: 10.1016/j.ejvs.2019.11.034. Epub 2020 Jan 31.
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 C and C CEAP limbs.
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 (C: n = 50; C 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.
On NIr-I, the diameters, trajectories, and colouration of SVNs of C limbs appeared more irregular than SVNs of C 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 (C) to 16.2 ± 11.9 (C). While the SVN length seen in the VS images from C limbs was greater than observed in C 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 C CEAP SVN veins was 5.8 mm (interquartile range [IQR] 4.3-7.5 mm), while the median diameter in C SVN limbs was 2.6 mm (IQR 2.0-3.6 mm) (p < .001).
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 C and C limbs, and the factors causing them.
皮下静脉网络 (SVN) 用肉眼难以看到。近红外光 (NIr-I) 据称可以改善这一点。本观察性研究的目的是调查不同方法之间是否存在差异；量化 SVN 的长度和直径；并确认它们在 C 和 C CEAP 肢体之间是否不同。
共使用了 4796 张图像，其中一半来自可见光谱 (VS)，另一半来自近红外光谱 (NIrS)，属于 109 名女性（C：n=50；C CEAP：n=59），通过视觉分析建立 SVN 的形态特征。使用 Photoshop CS4，通过排除整个肢体的图像后，对 3052 张图像进行数字分析，获得 SVN 直径和长度。
在 NIr-I 上，C 肢体的 SVN 直径、轨迹和颜色比 C 肢体的 SVN 显得更不规则。与 VS 图像相比，NIr-I 允许在两组中可视化更长的 SVN（p<.010）。这种能力从 C 肢体的 2.6±0.9 倍（C）到 16.2±11.9（C）不等。虽然 C 肢体 VS 图像中看到的 SVN 长度大于 C 肢体（p<.001），但 NIr-I 图像之间的差异仅存在于小腿外侧（p=.016）。使用 NIr-I，C CEAP SVN 静脉的中位数直径为 5.8mm（四分位距 [IQR] 4.3-7.5mm），而 C SVN 肢体的中位数直径为 2.6mm（IQR 2.0-3.6mm）（p<.001）。
NIr-I 比肉眼更能揭示 SVN 的特征。需要进一步研究以确定 C 和 C 肢体中 SVN 变化的意义以及引起这些变化的因素。
