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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">bioph</journal-id><journal-title-group><journal-title xml:lang="ru">Biomedical Photonics</journal-title><trans-title-group xml:lang="en"><trans-title>Biomedical Photonics</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2413-9432</issn><publisher><publisher-name>Non-profit partnership for development of domestic photodynamic therapy and photodiagnosis</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.24931/2413-9432-2023-12-3-4-10</article-id><article-id custom-type="elpub" pub-id-type="custom">bioph-602</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group></article-categories><title-group><article-title>Классификация внутричерепных опухолей на основе оптико-спектрального анализа</article-title><trans-title-group xml:lang="en"><trans-title>Classification of intracranial tumors based on optical-spectral analysis</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Романишкин</surname><given-names>И. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Romanishkin</surname><given-names>I. D.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><email xlink:type="simple">igor.romanishkin@nsc.gpi.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Савельева</surname><given-names>Т. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Savelieva</surname><given-names>T. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Оспанов</surname><given-names>А.</given-names></name><name name-style="western" xml:lang="en"><surname>Ospanov</surname><given-names>A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Линьков</surname><given-names>К. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Linkov</surname><given-names>K. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шугай</surname><given-names>С. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Shugai</surname><given-names>S. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-4"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Горяйнов</surname><given-names>С. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Goryajnov</surname><given-names>S. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-4"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Павлова</surname><given-names>Г. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Pavlova</surname><given-names>G. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-5"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Пронин</surname><given-names>И. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Pronin</surname><given-names>I. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-4"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Лощенов</surname><given-names>В. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Loschenov</surname><given-names>V. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Москва</p></bio><bio xml:lang="en"><p>Moscow</p></bio><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Институт общей физики им. А.М. Прохорова Российской академии наук<country>Россия</country></aff><aff xml:lang="en">Prokhorov General Physics Institute of the Russian Academy of Sciences<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Институт общей физики им. А.М. Прохорова Российской академии наук; Национальный исследовательский ядерный университет «МИФИ»<country>Россия</country></aff><aff xml:lang="en">Prokhorov General Physics Institute of the Russian Academy of Sciences; National Research Nuclear University MEPhI<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru">Национальный исследовательский ядерный университет «МИФИ»<country>Россия</country></aff><aff xml:lang="en">National Research Nuclear University MEPhI<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru">НМИЦ нейрохирургии имени академика Н.Н. Бурденко<country>Россия</country></aff><aff xml:lang="en">N.N. Burdenko National Medical Research Center of Neurosurgery<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-5"><aff xml:lang="ru">НМИЦ нейрохирургии имени академика Н.Н. Бурденко; Институт высшей нервной деятельности и нейрофизиологии Российской академии наук<country>Россия</country></aff><aff xml:lang="en">N.N. Burdenko National Medical Research Center of Neurosurgery; Institute of Higher Nervous Activity and Neurophysiology of the Russian Academy of Sciences<country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>23</day><month>10</month><year>2023</year></pub-date><volume>12</volume><issue>3</issue><fpage>4</fpage><lpage>10</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Романишкин И.Д., Савельева Т.А., Оспанов А., Линьков К.Г., Шугай С.В., Горяйнов С.А., Павлова Г.В., Пронин И.Н., Лощенов В.Б., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Романишкин И.Д., Савельева Т.А., Оспанов А., Линьков К.Г., Шугай С.В., Горяйнов С.А., Павлова Г.В., Пронин И.Н., Лощенов В.Б.</copyright-holder><copyright-holder xml:lang="en">Romanishkin I.D., Savelieva T.A., Ospanov A., Linkov K.G., Shugai S.V., Goryajnov S.A., Pavlova G.V., Pronin I.N., Loschenov V.B.</copyright-holder><license license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.pdt-journal.com/jour/article/view/602">https://www.pdt-journal.com/jour/article/view/602</self-uri><abstract><p>Мотивацией проведения настоящего исследования послужила необходимость развития методов срочной интраоперационной биопсии при проведении операций по поводу удаления внутричерепных опухолей. На основании опыта предыдущей совместной работы ИОФ РАН и НМИЦ нейрохирургии  им. Н.Н. Бурденко по внедрению в клиническую практику методов флуоресцентной спектроскопии был разработан подход, комбинирующий различные оптико-спектральные  методики, такие как спектроскопия  аутофлуоресценции, флуоресценции  5-АЛК индуцированного  протопорфирина  IX, диффузного  отражения  широкополосного излучения,  по которому можно определять концентрацию гемоглобина в тканях и их оптическую  плотность,  спектроскопия  комбинационного  рассеяния, являющаяся методом молекулярной спектроскопии, позволяющим детектировать различные молекулы в тканях за счета колебаний отдельных характерных связей в молекулах. Такое разнообразие оптико-спектральных характеристик  затрудняет их непосредственный анализ хирургом во время операции, как это обычно реализуется в случае флуоресцентных методов – по превышению некоторого порога интенсивности флуоресценции с определенной степенью достоверности можно судить о том, находится ли в зоне исследования нормальная или опухолевая ткань. В случае, если число параметров превышает пару десятков, необходимо использование алгоритмов машинного обучения для построения  системы поддержки принятия  решений хирурга  во время операции. Настоящая работа представляет исследования в этом направлении. Проведенный нами ранее статистический  анализ данных оптико-спектральных характеристик  позволил выделить статистически  значимые спектральные диапазоны для анализа, репрезентирующие  диагностически  важные компоненты тканей. Исследования методов понижения размерности вектора оптико-спектральных признаков  и методов кластеризации исследуемых образцов также позволили приблизиться к реализации метода автоматической классификации. Важно отметить, что задача классификации может быть использована в двух приложениях – для дифференциации различных опухолей и для дифференциации различных частей одной (центр, перифокальная зона, норма) опухоли. В настоящей работе представлены результаты наших исследований в первом направлении. Мы исследовали сочетание нескольких методов и показали возможность дифференциации глиальных и менингеальных опухолей на основании предложенного метода оптико-спектрального анализа.</p></abstract><trans-abstract xml:lang="en"><p>The motivation for the present study was the need to develop methods of urgent intraoperative biopsy during surgery for removal of intracranial tumors. Based on the experience of previous joint work of GPI RAS and N.N. Burdenko National Medical Research Center of Neurosurgery to introduce fluorescence spectroscopy methods into clinical practice, an approach combining  various optical-spectral techniques, such as autofluorescence spectroscopy, fluorescence of 5-ALA induced protoporphyrin IX, diffuse reflection of broadband light, which can be used to determine hemoglobin concentration in tissues and their optical density, Raman spectroscopy, which is a spectroscopic method that allows detection of various molecules in tissues by vibrations of individual characteristic molecular bonds. Such a variety of optical and spectral characteristics makes it difficult for the surgeon to analyze them directly during surgery, as it is usually realized in the case of fluorescence methods – tumor tissue can be distinguished from normal with a certain degree of certainty by fluorescence intensity exceeding  a threshold value. In case the number of parameters exceeds a couple of dozens, it is necessary to use machine learning algorithms  to build a intraoperative decision support system for the surgeon. This paper presents research in this direction. Our earlier statistical analysis of the optical-spectral features allowed identifying  statistically significant spectral ranges for analysis of diagnostically  important tissue components. Studies of dimensionality reduction techniques of the optical-spectral feature vector and methods of clustering of the studied samples also allowed us to approach the implementation  of the automatic classification method. Importantly, the classification task can be used in two applications  – to differentiate between different tumors and to differentiate between different parts of the same (center, perifocal zone, normal) tumor. This paper presents the results of our research in the first direction. We investigated the combination of several methods and showed the possibility of differentiating glial and meningeal tumors based on the proposed optical-spectral analysis method.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>оптическая спектроскопия</kwd><kwd>внутричерепные опухоли</kwd><kwd>машинное обучение</kwd></kwd-group><kwd-group xml:lang="en"><kwd>optical spectroscopy</kwd><kwd>intracranial tumors</kwd><kwd>machine learning</kwd></kwd-group><funding-group xml:lang="en"><funding-statement>This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 075-15-2021-1343 dated October 4, 2021).</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Majós C., Julià-Sapé M., Alonso J. et al. 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