Multimodal optical diagnostics of the microhaemodynamics in upper and lower limbs

The introduction of optical non-invasive diagnostic methods into clinical practice can substantially advance in the detection of early microcirculatory disorders in patients with different diseases. This paper is devoted to the development and application of the optical non-invasive diagnostic approach for the detection and evaluation of the severity of microcirculatory and metabolic disorders in rheumatic diseases and diabetes mellitus. The proposed methods include the joint use of laser Doppler flowmetry, absorption spectroscopy and fluorescence spectroscopy in combination with functional tests. This technique showed the high diagnostic importance for the detection of disturbances in peripheral microhaemodynamics. These methods have been successfully tested as additional diagnostic techniques in the field of rheumatology and endocrinology. The sensitivity and specificity of the proposed diagnostic procedures have been evaluated.<br/

Novel measure for the calibration of laser Doppler flowmetry devices

The metrological basis for optical non-invasive diagnostic devices is an unresolved issue. A major challenge for laser Doppler flowmetry (LDF) is the need to compare the outputs from individual devices and various manufacturers to identify variations useful in clinical diagnostics. The most common methods for instrument calibration are simulants or phantoms composed of colloids of light-scattering particles which simulate the motion of red blood cells based on Brownian motion. However, such systems have limited accuracy or stability and cannot calibrate for the known rhythmic components of perfusion (0.0095-1.6 Hz). To solve this problem, we propose the design of a novel technique based on the simulation of moving particles using an electromechanical transducer, in which a precision piezoelectric actuator is used (e.g., P-602.8SL with maximum movement less than 1 mm). In this system, Doppler shift is generated in the layered structure of different solid materials with different optical light diffusing properties. This comprises a fixed, light transparent upper plane-parallel plate and an oscillating fluoroplastic (PTFE) disk. Preliminary studies on this experimental setup using the LDF-channel of a "LAKK-M" system demonstrated the detection of the linear portion (0-10 Hz with a maximum signal corresponding to Doppler shift of about 20 kHz) of the LDF-signal from the oscillating frequency of the moving layer. The results suggest the possibility of applying this technique for the calibration of LDF devices

Noninvasive control of rhodamine-loaded capsules distribution in vivo

Using fluorescence spectroscopy system with fibre-optical probe, we investigated the dynamics of propagation and circulation in the microcirculatory system of experimental nanocapsules fluorescent-labelled (rhodamine TRITC) nanocapsules. The studies were carried out in clinically healthy Wistar rats. The model animals were divided into control group and group received injections of the nanocapsules. The fluorescent measurements conducted transcutaneously on the thigh surface. The administration of the preparation with the rhodamine concentration of 5 mg/kg of animal weight resulted in twofold increase of fluorescence intensity by reference to the baseline level. As a result of the study, it was concluded that fluorescence spectroscopy can be used for transdermal measurements of the rhodamine-loaded capsules in vivo

The study of synchronization of rhythms of microvascular blood flow and oxygen saturation during adaptive changes

Multi-functional laser non-invasive diagnostic systems, such as "LAKK-M", allow the study of a number of microcirculatory parameters, including blood microcirculatory index (Im) (by laser Doppler flowmetry, LDF) and oxygen saturation (StO2) of skin tissue (by tissue reflectance oximetry, TRO). Such systems may provide significant information relevant to physiology and clinical medicine. The aim of this research was to use such a system to study the synchronization of microvascular blood flow and oxygen saturation rhythms under normal and adaptive change conditions. Studies were conducted with 8 healthy volunteers - 3 females and 5 males of 21-49 years. Each volunteer was subjected to basic 3 minute tests. The volunteers were observed for between 1-4 months each, totalling 422 basic tests. Measurements were performed on the palmar surface of the right middle finger and the forearm medial surface. Wavelet analysis was used to study rhythmic oscillations in LDF- and TRO-data. Tissue oxygen consumption (from arterial and venal blood oxygen saturation and nutritive flux volume) was calculated for all volunteers during "adaptive changes" as (617±123 AU) and (102±38 AU) with and without arteriovenous anastomoses (AVAs) respectively. This demonstrates increased consumption compared to normal (495±170 AU) and (69±40 AU) with and without AVAs respectively. Data analysis demonstrated the emergence of resonance and synchronization of rhythms of microvascular blood flow and oxygen saturation as an adaptive change in myogenic oscillation (vasomotion) resulting from exercise and potentially from psychoemotional stress. Synchronization of myogenic rhythms during adaptive changes suggest increased oxygen consumption resulting from increased microvascular blood flow velocity

SHORT- AND MIDDLE-TERM RESULTS OF KNEE JOINT REPLACEMENT WITH ZIMMER NexGen CR AND LPS IMPLANTS

The article presents the experience gained by orthopedic unit of Saratov Regional Clinical Hospital at knee joint replacement with modern implants. We analyzed use of Zimmer NexGen CR and LPC implants for initial total knee joint replacement in 285 patients. The monitoring continued for 5 years. Good and excellent results were observed in 92% of cases. Pyogenic complications were observed in 2.3% of cases. The article describes the methods of surgical intervention and post-surgical rehabilitation. We consider our experience with Zimmer NexGen LPS and CR knee-joint implants as positive and prospective for further use

Optimization of preoperative planning and intraoperative navigation at the shoulder replacement

There were 105 patients with shoulder replacement under our supervision (terms of supervision were up to 10 years). There were 43 men and 62 women. Age of patients was from 29 to 80 years. Two ways of optimization of shoulder replacement are offered: "Method of preoperative determination of the sizes of a head of shoulder joint endoprosthesis" (Patent of the Russian Federation N 2469670 d.d. 12.20.2012) and "Method for intraoperative navigation of a shoulder stem of joint" (Patent of the Russian Federation N 2467725 d.d. 11.27.2012). We reached the improvement of quality of the operation due to the fact of an installation of the implants which are as much as possible close to the anatomy of a normal shoulder joint by size and position

Primary endo-prothesis of shoulder joint at heavy traumatic damages of proximal segment of a shoulder bone and their consequences

Under our supervision there were 123 patients with terms of supervision till 7 years, with fractures,fracture-dislocations of an area of a shoulder joint and chronic damages of this area. There were 57 men and 66 women. All the patients were from 38 to 83 years old, the average age was 55,8 years. 44 patients had various kinds of an osteosynthesis and 79 - endoprosthesis of a shoulder joint. It was proved, that in patients of the senior age group, the expressed bony rarefication, a heavy accompanying pathology of a shoulderjoint (arthrosis of 2-3 grades, defeat of a joint at a number system diseases, etc.) and also at the treatment of consequences of traumas are unconditional, the preference should be given to endoprosthesis of a humeral joint, as to more effective method of treatment

Wearable laser Doppler sensors for evaluating the nutritive and shunt blood flow

This study is devoted to the trials of wearable diagnostic system that implements the laser Doppler flowmetry technique to analyse the blood microcirculation. We do preliminary test with involvement of limited group of healthy volunteers of different age and in patients with type 2 diabetes. During the series of measurements, the microcirculation parameters was measured for 10 minutes in the palmar surfaces of the big toes and in the inner sides of the upper thirds of the shins. A statistically significant differences was found in bypass index, nutritive and shunt blood ow in shins between older group of volunteers and patients' group as well as in shunt blood flow in fingers between younger and older groups of volunteers

Wearable sensor system for multipoint measurements of blood perfusion: pilot studies in patients with diabetes mellitus

The growing interest in the development of new wearable electronic devices for mobile healthcare provides great opportunities for the development of methods for assessing blood perfusion in this direction. Laser Doppler flowmetry (LDF) is one of the promising methods. A fine analysis of capillary blood ow structure and rhythm in the time and frequency domains, coupled with a new possibility of round-the-clock monitoring can provide valuable diagnostic information about the state of microvascular blood ow. In this study, wearable implementation of laser Doppler flowmetry was utilised for microcirculatory function assessment in patients with diabetes and healthy controls of two distinct age groups. Four wearable laser Doppler flowmetry monitors were used for the analysis of blood microcirculation. Thirty-seven healthy volunteers and 18 patients with type 2 diabetes mellitus participated in the study. The results of the studies have shown that the average perfusion differs between healthy volunteers of distinct age groups and between healthy volunteers of the younger age group and patients with diabetes mellitus. It was noted that the average level of perfusion measured on the wrist in the two groups of healthy volunteers has no statistically significant differences found in similar measurements on the fingertips. The wearable implementation of LDF can become a truly new diagnostic interface to monitor cardiovascular parameters, which could be of interest for diagnostics of conditions associated with microvascular disorders

Нейровизуализационные особенности строения головного мозга у детей с детским церебральным параличом, полученные методом магнитно-резонансной трактографии

Aim. To perform quantitative evaluation of the degree of white matter tract abnormalities in children with spastic cerebral palsy by magnetic resonance tractography to determine severity of the disease, as well as to carry out a dynamic assessment of treatment effectiveness.Materials and methods. The study included 46 children (32 males, 14 females; average age 5.4 ± 1.1 years). The participants were divided into two groups. The experimental group consisted of 23 children with spastic cerebral palsy. The control group included 23 children without any neurological disorder. Examination of the brain was performed on the Siemens Essenza 1,5 Т system (Siemens, Germany) and included magnetic resonance tractography to reconstruct the major white matter tracts. The number of fibers, average fractional anisotropy value, apparent diffusion coefficient, and coefficient of myelination of major white matter tracts in the brain were calculated and analyzed.Results. We found a significant difference in the above-stated parameters between the groups. The experimental group showed a decrease in the absolute number of fibers at the central and posterior segments of the corpus callosum, corticospinal tracts, and left inferior longitudinal fasciculus. Besides, we detected a decrease in fractional anisotropy at 2–5 segments of the corpus callosum and right lateral corticospinal tract, an increase in the apparent diffusion coefficient at 2, 4, and 5 segments of the corpus callosum and left lateral corticospinal tract, and a decrease in the myelination coefficient in all the examined tracts, except for superior longitudinal fasciculus. We revealed a positive correlation between the intensity of the motor disturbance and the coefficient of myelination at the anterior corpus callosum and inferior longitudinal fasciculus.Conclusion. Magnetic resonance tractography is an informative technique for unbiased evaluation of white matter tract anatomy, as well the level and degree of motor tract damage. The most useful characteristics of white matter tract anatomy are the absolute number of fibers in the tract, fractional anisotropy, and coefficient of myelination. Some of them correlated with the intensity of motor disturbance, so they can be regarded as potential predictors of rehabilitation potential. Цель. Количественная оценка степени нарушений развития проводящих путей головного мозга у детей со спастическими формами детского церебрального паралича (ДЦП) методами магнитно-резонансной (МР) трактографии для определения тяжести заболевания, а также оценка динамики эффективности лечения.Материалы и методы. Обследованы 46 детей 4–7 лет (средний возраст (5,4 ± 1,1) лет), из них 14 девочек (33%) и 32 мальчика (66%). Пациенты разделены на две группы. Исследуемую группу составили 23 пациента со спастическими формами ДЦП. В контрольную группу вошли 23 ребенка без неврологического дефицита. Исследование головного мозга проводилось на МР-томографе Siemens Essenza 1,5 Т (Siemens, Германия) и включало метод МР-трактографии. Были рассчитаны и обработаны: количество волокон, средний показатель фракционной анизотропии, коэффициент диффузии, коэффициент миелинизации основных проводящих путей головного мозга.Результаты. Выявлена достоверная разница указанных выше показателей между пациентами исследуемой и контрольной групп. У детей с ДЦП отмечалось снижение абсолютного количества волокон в области центральных и заднего сегментов мозолистого тела, кортикоспинальных трактов и левого нижнего продольного пучка. Также определялось снижение показателя фракционной анизотропии волокон в области 2–5-го сегментов мозолистого тела, правого кортикоспинального тракта; повышение коэффициента диффузии в области 2, 4, 5-го сегментов и левого кортикоспинального тракта; снижение коэффициента миелинизации во всех исследуемых трактах, за исключением верхних продольных пучков. Выявлена положительная корреляция между  выраженностью моторного дефицита и коэффициентом миелинизации в области переднего сегмента мозолистого тела и нижних продольных пучков.Заключение. МР-трактография является информативным методом объективной оценки организации проводящих путей головного мозга, уровня и степени поражения моторных трактов. Наиболее информативными характеристиками организации проводящих путей являются абсолютное количество волокон в тракте, показатель фракционной анизотропии, а также расчетный показатель – коэффициент миелинизации. Некоторые из выявленных изменений коррелировали с выраженностью моторного дефицита, что позволяет рассматривать их как потенциальные предикторы реабилитационного прогноза