The evaluation of the microcirculatory bed functional state and the identification of angiospastic disorders with related complications, when the pathological changes are reversible, have an important role in medical practice. The aim of this study was to evaluate the possibility of using optical noninvasive methods and the cold pressor test to solve this problem. A total of 33 patients with rheumatological diseases and 32 healthy volunteers were included in the study. Laser Doppler flowmetry, tissue reflectance oximetry and pulse oximetry were used as optical noninvasive methods. The parameters were recorded before, immediately after and 20 min after the cold pressor test. Based on the measured parameters, the complex parameters of the microcirculatory bed were calculated. A detailed statistical analysis of the parameter changes for each individual in the two groups displayed diverse microcirculatory bed parameter responses upon cold exposure, with differing recovery of parameters after CPT. New diagnostic criteria were proposed for the identification of angiospastic disorders. According to the proposed criteria, 27 people of the volunteers group were confirmed to not display any disorders. In the patient group, however, 18 people were observed to have a relatively normal functional state of the microcirculatory bed, while 15 people were observed to have a possible tendency to angiospasm. To highlight the differences between a relatively normal state and presence of angiospastic disorders, statistical analysis of experimental data was carried out, which revealed significant differences. Further analysis of data with angiospastic disorders identified a relationship between their diagnoses and the results of laboratory studies. Thus, the evaluation of combined noninvasive optical diagnostic method use, the cold pressor test and proposed diagnostic criteria showed a positive result. This approach can be used to detect the presence of possible angiospastic disorders and related complications, as well as microcirculatory bed disorders against the background of other diseases.

为了提高血氧饱和度光谱测量的精度和可靠性, 增强血氧饱和度测量数据的有效性, 提出了基于试验方差分析的血氧测量波长选取的方法。 通过分析不同波长组合对应的血氧饱和度系数分布情况, 合理地利用统计理论, 从中选取较好的波长组合。 实验中以不同血氧饱和度临床数据为基础, 建立了不同波长组合(660和940 nm, 660和805 nm, 805和940 nm)计算出的血氧饱和度系数的单因素试验方差分析模型, 参照分析模型中的F指标和p参数, 比较分析不同波长组合的显著性, 进而从光谱数据中选取出相对较好的波长组合, 为进一步建模分析提供了可靠的中间数据。 结果表明, 选取660和805 nm的波长组合引入的总误差相对较小, 能更显著的代表血氧饱和度的变化, 相比其他的波长组合进行分析能够提高血氧测量精度。 本研究将试验方差分析方法用于血氧测量中波长组合的优选, 效果显著, 为血氧饱和度的测量和其他相关光谱的特征波长选取以及定量分析提供了新思路。 试验方差分析方法有助于从光谱中提取代表被测量的有效信息。

Measurement of both oxygen saturation and blood flow in the retinal vessels has proved to give important information about the eye health and the onset of eye pathologies such as diabetic retinopathy. In this study, we present the implementation, on a commercially available fundus camera, of a retinal imager and a retina blood flow velocimeter. The retinal imager uses division of aperture to acquire nine wavelength-dependent sub-images of the retina. Careful consideration is taken to improve image transfer by measuring the optical properties of the fundus camera and modeling the optical train in Zemax. This part of the setup is calibrated with optical phantoms of known optical properties that are also used to build a lookup table (LUT) linking phantom optical properties to measured reflectance. The retina blood flow velocimeter relies on tracking clusters of erythrocytes and uses a fast acquisition camera attached to a zoom lens, with a green illumination LED-engine. Calibration is provided using a calibrated quartz capillary tube and human blood at a known flow rate. Optical properties of liquid phantoms are retrieved from measured reflectance using the LUT, and blood flow measurements in the retina are presented.

We have examined ten human subjects with a previously developed instrument for near-infrared diffuse spectral imaging of the female breast. The instrument is based on a tandem, planar scan of two collinear optical fibers (one for illumination and one for collection) to image a gently compressed breast in a transmission geometry. The optical data collection features a spatial sampling of 25 points/cm² over the whole breast, and a spectral sampling of 2 points/nm in the 650– 900nm wavelength range. Of the ten human subjects examined, eight are healthy subjects and two are cancer patients with unilateral invasive ductal carcinoma and ductal carcinoma in situ, respectively. For each subject, we generate second-derivative images that identify a network of highly absorbing structures in the breast that we assign to blood vessels. A previously developed paired-wavelength spectral method assigns oxygenation values to the absorbing structures displayed in the second-derivative images. The resulting oxygenation images feature average values over the whole breast that are significantly lower in cancerous breasts (69±14%, n = 2) than in healthy breasts (85±7%, n = 18) (p < 0.01). Furthermore, in the two patients with breast cancer, the average oxygenation values in the cancerous regions are also significantly lower than in the remainder of the breast (invasive ductal carcinoma: 49±11% vs 61±16%, p < 0.01; ductal carcinoma in situ: 58±8% vs 77±11%, p < 0.001).