27 research outputs found
Application of the method of decomposition of lidar signal-to-noise ratio to the assessment of laser instruments for gaseous pollution detection
A general methodology for rating both performance
and potential of lidar systems used for detection of atmospheric
trace constituents including pollutants and gas leaks
is developed. By individually examining and decomposing the
contribution of both lidar system parameters and atmospheric
operating conditions on signal-to-noise-ratio, a generalized figure
of merit, V, for lidar quality is introduced and evolved.
Computer simulations based on V and atmospheric parameters
are carried out to determine achievable lidar performance.
A simple design procedure is outlined for determination of lidar
instrumentation parameters to ensure the best monitoring
efficiency for a given set of initial parameters/requirements,
including operation range, minimum detectable gas concentration,
and so on.Postprint (published version
Expediency of performing organ-saving operations in multifocal / multicentric breast cancer
The incidence of multifocal (MF) and multicentric (MC) carcinomas varies widely among clinical studies, depending on definitions and methods for pathological sampling. Magnetic resonance imaging is increasingly used because it can help identify additional and conventionally occult tumors with high sensitivity. However, false positive lesions might incorrectly influence treatment decisions. therefore, preoperative biopsies must be performed to avoid unnecessary surgery. Most studies have shown higher lymph node involvement rates in MF/MC tumors than in unifocal tumors. However, the rate of local recurrences is usually low after breast conservative treatment (BCt) of MC/MF tumors. It has been suggested that BCt is a reasonable option for MC/MF tumors in women aged 50-69 years, with small tumors and absence of extensive ductal carcinoma in situ. A metaanalysis showed an apparent decreased overall survival in MC/MF tumors but data are controversial. Surgery should achieve both acceptable cosmetic results and negative margins, which requires thorough preoperative radiological workup and localization of lesions. Boost radiotherapy techniques must be evaluated since double boosts might result in increased toxicity, namely fibrosis. In conclusion, BCt is feasible in selected patients with MC/MF but the choice of surgery must be discussed in a multidisciplinary team comprising at least radiologists, surgeons and radiotherapists.Частота встречаемости мультифокальных (МФ) и мультицентричных (МЦ) карцином широко варьируется среди клинических исследований в зависимости от определений и методов морфологического исследования. Применение магнитно-резонансной томографии широко распространено в связи с возможностью точного распознания дополнительных скрытых опухолей. Однако, ложноположительные поражения могут привести к некорректному выбору лечения. Таким образом, необходимо проведение дооперационных биопсий во избежание неоправданного хирургического вмешательства. Большинство исследований продемонстрировали более высокие показатели поражения лимфатических узлов при МФ/МЦ опухолях по сравнению с унифокальными. однако, частота местного рецидива обычно ниже после проведения органосохраняющего лечения при МФ/МЦ опухолях. Предполагается, что органосохраняющее лечение является целесообразным при МФ/МЦ опухолях в случае с пациентами в возрасте 50-69 лет с небольшими опухолями и отсутствием обширной протоковой карциномы in situ. Согласно метаанализу, наблюдаются низкие показатели общей выживаемости при МФ/МЦ опухолях, однако данный факт остается под вопросом. Хирургическое вмешательство должно обеспечивать как должный косметический результат, так и гистологически чистые края резекции, что требует тщательного рентгенологического исследования и локализации поражений. Необходимо тщательно изучить особенности бустерного облучения, поскольку двойная доза облучения может привести к повышенной токсичности, в частности к развитию фиброза. В заключение, органосохраняющее лечение целесообразно в случае с определенной группой пациентов с МФ/МЦ опухолями, однако решение относительно выбора хирургического вмешательства должно приниматься в рамках междисциплинарного взаимодействия рентгенолога, хирургов и специалистов по лучевой терапии
Chemical pleurodesis using bleomycin in treatment of patients with transsudative pleural effusion in hepatic failure
OBJECTIVE. The authors analyzed the efficacy of bleomycin application as sclerosing agent in patients with transudative pleural effusion in consequence of hepatic failure. MATERIAL AND METHODS. The research included 7 patients with right side hepatic transudative pleural effusion who didn’t respond to conservative medical treatment. Drainage of the right pleural cavity with following injection of bleomycin were performed for all the patients. RESULTS. This procedure was effective in 6 out of 7 patients (86 %). There was a single case of recurrence and lethal outcome (14 %) due to hepatic coma. There weren’t noted any severe side effects during 6 months after induction of bleomycin. CONCLUSIONS. Pleurodesis using bleomycin appeared to be effective and safe method of treatment for patients with hepatic transudative pleural effusions
INTRAOPERATIVE DETECTION OF SENTINEL LYMPH NODES USING INFRARED IMAGING SYSTEM IN LOCAL NON-SMALL CELL CARCINOMA OF LUNG
The article presents the results of the first domestic experience of intraoperative fluorescence mapping of sentinel lymph nodes in lung cancer. The research included 10 patients, who underwent surgery over the period of time from September 2013 to May 2014. After performing thoracotomy, the solution of indocyanine green (ICG) was injected using subpleural position above the tumor in 3-4 points. Fluorescence (ICG) image guided surgery was carried out by using infrared radiation (wave length 808 nm) on lung surface, root of lung, mediastinum in real time. Fluorescence lymph nodes were mapped. In case that metastatic lesions weren’t revealed in sentinel lymph nodes, they weren’t noted in other nodes. Method specificity consisted of 100%. Biopsy and histological study of sentinel lymph nodes mapped during fluorescence (ICG) image guided surgery could be useful for prevention of lymphodissection in patients with non-small cell carcinoma of lung
Theory of the spinodal decomposition of a solid solution in the approximation of a screened Coulomb interaction between ions
TRANSTHORACAL PUNCTURE BIOPSY UNDER ULTRASONIC INDUCTION IN TUMORS OF THE ANTERIOR MEDIASTINUM
Differential diagnostics of tumors of anterior mediastinum is one of the most difficult problems of thoracic surgery and oncology. The authors conducted a retrospective analysis of the results of transthoracal puncture biopsy under ultrasonic induction in 44 patients with the tumors of the anterior mediastinum. Transthoracal biopsy was carried out using the device for biopsy (Multiple Biopsy Device-MBD-23) and ultrasonic scanner (Voluson 730 Expert), the patients being under intravenous (38 patients) and under local (6 patients) anesthetization. The diagnosis was made as a result of morphological research in all 100% of patients, the biopsy being performed the second time in one patient. The general information value of puncture biopsy under ultrasonic induction was 98%. A complication (localized pneumothorax, cupping off by itself) took place only in one of the follow-up study (2%). The analysis of presented material let the authors make a conclusion that transthoracal puncture biopsy under ultrasonic induction is a safe and highly informative method of diagnostics of tumors of the anterior mediastinum in selected patients
Infrared fluorescence guided pleural biopsy during thoracoscopy
OBJECTIVE. The authors developed methods and assessment of efficacy of infrared fluorescence imaging of pleural carcinomatosis using indocyanine green (ICG). MATERIAL AND METHODS. The prospective study included 14 patients with malignant pleural carcinomatosis. All patients underwent standard thoracoscopy with pleural biopsy, then pleural cavity was examined under fluorescence control using ICG solution. Comparison of accuracy of biopsy materials obtained in white light and fluorescence was made. RESULTS. Signs of malignancy had 21 biopsy specimens out of 28, which were obtained in white light (in 12 patients out of 14). Research of biopsy specimens using fluorescence allowed doctors to make the precise diagnosis in all 14 patients, with 33 out of 34 biopsy materials being informative. CONCLUSIONS. Intraoperative application of infrared ICG fluorescence developed accuracy of biopsy and histological verification of the diagnosis