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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">neurosurgery</journal-id><journal-title-group><journal-title xml:lang="ru">Нейрохирургия</journal-title><trans-title-group xml:lang="en"><trans-title>Russian journal of neurosurgery</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1683-3295</issn><issn pub-type="epub">2587-7569</issn><publisher><publisher-name>Издательский дом "МедИНК"</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17650/1683-3295-2021-23-1-62-73</article-id><article-id custom-type="elpub" pub-id-type="custom">neurosurgery-1012</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>ОРИГИНАЛЬНАЯ РАБОТА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL REPORT</subject></subj-group></article-categories><title-group><article-title>Количественная оценка степени вовлеченности пирамидного тракта при внутримозговых опухолях</article-title><trans-title-group xml:lang="en"><trans-title>The quantitative evaluation of cortico-spinal tract involvement in malignant intracerebral tumors</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5326-9685</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ермолаев</surname><given-names>А. Ю.</given-names></name><name name-style="western" xml:lang="en"><surname>Ermolaev</surname><given-names>A. Yu.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Антон Юрьевич Ермолаев</p><p>Россия, 603155 Нижний Новгород, ул. Минина, 34</p><p>Россия, 603126 Нижний Новгород, ул. Деловая, 11 / 1</p></bio><bio xml:lang="en"><p>11 / 1 Delovaya St., Nizhny Novgorod 603126, Russia</p><p>34 Minina St., Nizhny Novgorod 603155, Russia</p></bio><email xlink:type="simple">anton_ermolaeff@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-9484-6992</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кравец</surname><given-names>Л. Я.</given-names></name><name name-style="western" xml:lang="en"><surname>Kravets</surname><given-names>L. Ya.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Россия, 603155 Нижний Новгород, ул. Минина, 34</p><p>Россия, 603126 Нижний Новгород, ул. Деловая, 11 / 1</p></bio><bio xml:lang="en"><p>11 / 1 Delovaya St., Nizhny Novgorod 603126, Russia</p><p>34 Minina St., Nizhny Novgorod 603155, Russia</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2069-1710</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Клюев</surname><given-names>Е. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Klyuev</surname><given-names>E. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Россия, 603155 Нижний Новгород, ул. Минина, 34</p><p>Россия, 603126 Нижний Новгород, ул. Деловая, 11 / 1</p></bio><bio xml:lang="en"><p>11 / 1 Delovaya St., Nizhny Novgorod 603126, Russia</p><p>34 Minina St., Nizhny Novgorod 603155, Russia</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5723-7389</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Яшин</surname><given-names>К. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Yashin</surname><given-names>K. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Россия, 603155 Нижний Новгород, ул. Минина, 34</p><p>Россия, 603126 Нижний Новгород, ул. Деловая, 11 / 1</p></bio><bio xml:lang="en"><p>11 / 1 Delovaya St., Nizhny Novgorod 603126, Russia</p><p>34 Minina St., Nizhny Novgorod 603155, Russia</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-9429-5350</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Лобанова</surname><given-names>Е. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Lobanova</surname><given-names>E. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Россия, 603155 Нижний Новгород, ул. Минина, 34</p><p>Россия, 603126 Нижний Новгород, ул. Деловая, 11 / 1</p></bio><bio xml:lang="en"><p>11 / 1 Delovaya St., Nizhny Novgorod 603126, Russia</p><p>34 Minina St., Nizhny Novgorod 603155, Russia</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7519-0959</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Медяник</surname><given-names>И. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Medyanik</surname><given-names>I. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Россия, 603155 Нижний Новгород, ул. Минина, 34</p><p>Россия, 603126 Нижний Новгород, ул. Деловая, 11 / 1</p></bio><bio xml:lang="en"><p>11 / 1 Delovaya St., Nizhny Novgorod 603126, Russia</p><p>34 Minina St., Nizhny Novgorod 603155, Russia</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБОУ ВО «Приволжский исследовательский медицинский университет» Минздрава России; ГБУЗ НО «Нижегородский областной клинический онкологический диспансер» Минздрава России</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Privolzhsky Research Medical University; Nizhny Novgorod Regional Clinical Oncology Dispensary</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>04</day><month>05</month><year>2021</year></pub-date><volume>23</volume><issue>1</issue><elocation-id>62‑73</elocation-id><permissions><copyright-statement>Copyright &amp;#x00A9; Ермолаев А.Ю., Кравец Л.Я., Клюев Е.А., Яшин К.С., Лобанова Е.В., Медяник И.А., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Ермолаев А.Ю., Кравец Л.Я., Клюев Е.А., Яшин К.С., Лобанова Е.В., Медяник И.А.</copyright-holder><copyright-holder xml:lang="en">Ermolaev A.Y., Kravets L.Y., Klyuev E.A., Yashin K.S., Lobanova E.V., Medyanik I.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" 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.therjn.com/jour/article/view/1012">https://www.therjn.com/jour/article/view/1012</self-uri><abstract><p>Цель исследования – разработать метод количественной оценки степени вовлеченности пирамидного тракта при злокачественных внутримозговых опухолях.</p><sec><title>Материалы и методы</title><p>Материалы и методы. В ретроспективное исследование включено 62 пациента, которые перенесли хирургическое вмешательство в университетской клинике Приволжского исследовательского медицинского университета в 2017–2019 гг.: 16 – с метастазами, 29 – с контрастируемыми при магнитно-резонансной томографии (МРТ) глиомами III–IV степени злокачественности и 17 – с неконтрастируемыми глиомами II–III степени злокачественности. Протокол ведения пациентов включал предоперационную DTI-трактографию; интраоперационный нейромониторинг моторной функции с фиксацией минимальной силы тока прямой электростимуляции при получении моторного ответа; пред- и послеоперационную оценку двигательной функции в соответствии со шкалой MRC. Индекс вовлеченности тракта (ИВТ) рассчитывали посредством программной обработки данных предоперационных МРТ и МРТ-трактографии как отношение периметра части тракта, «погруженного» в патологический МРТ-сигнал, к площади его поперечного сечения.</p></sec><sec><title>Результаты</title><p>Результаты. Значения ИВТ от 0 до 1,75 были взаимосвязаны со степенью дооперационного пареза: большему значению ИВТ пирамидного тракта соответствовала большая выраженность пареза по MRC (p &lt;0,001, n = 62). Анализ значений ИВТ и результатов интраоперационной электростимуляции показал, что риск контакта с трактом возрастает при увеличении ИВТ (B0 = −1,6; Bi = 6,61; χ2 = 30,53; n = 62, p &lt;0,001). Прогностическое значение ИВТ ниже при повторном хирургическом вмешательстве и лучевой терапии в анамнезе.</p></sec><sec><title>Выводы</title><p>Выводы. Построение двухмерной модели взаимодействия опухоли и тракта с количественным выражением степени его вовлеченности (ИВТ) может быть использовано как дополнительный источник объективной информации при планировании первичного хирургического лечения у пациентов с внутримозговыми опухолями.</p></sec></abstract><trans-abstract xml:lang="en"><p>The aim of the study was development of the method for preoperative quantitative evaluation of pyramidal tract and tumor relationship in malignant intracerebral tumors.</p><sec><title>Materials and methods</title><p>Materials and methods. The retrospective analysis of 62 patients underwent surgery at the Department of Neurosurgery of Privolzhsky Research Medical University in 2017–2019, was performed. The patients were divide in 3 groups: metastatic brain tumor (n = 16); contrast-enhanced gliomas (grade III–IV); contrast-nonenhanced gliomas (grade II–III). The following protocol was implemented for all patients: preoperative DTI-tractography; intraoperative direct subcortical electrical stimulation with fixation of the minimum current intensity at receiving the motor response; pre- and postoperative motor function assessment using MRC-scale. Tract Involvement Index (TII) based on the ratio of the perimeter of the part of the tract involvement in pathological MRI-signal to its cross-section area was calculated using image processing of preoperative MRI and MRI-tractography data.</p></sec><sec><title>Results</title><p>Results. The association between TII values (from 0 to 1.75) and the severity of pre-operative paresis was demonstrated. We have discovered that the greater value of the pyramidal TII was corresponded to the greater severity of the paresis in MRC (p &lt;0.001, n = 62). The analysis of TII values and intraoperative motor direct subcortical mapping results showed an increase in risk of contact with a tract at higher TII value (B0 = −1.6; Bi = 6.61; χ2 = 30.53; n = 62, p &lt;0.001). The TII demonstrates better prognostic value in patients without radiation therapy in anamnesis.</p></sec><sec><title>Conclusions</title><p>Conclusions. The method for preoperative quantitative evaluation of pyramidal tract and tumor relationship using TII calculation can provide additional information for planning surgical treatment in patients with intracerebral tumors without radiation treatment in the history.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>опухоли мозга</kwd><kwd>опухоли пирамидного тракта</kwd><kwd>DTI-трактография</kwd><kwd>интраоперационный нейрофизиологической мониторинг</kwd><kwd>прямая электростимуляция</kwd></kwd-group><kwd-group xml:lang="en"><kwd>brain tumors</kwd><kwd>motor areas tumor surgery</kwd><kwd>diffusion tensor tractography</kwd><kwd>intraoperative neurophysiological monitoring</kwd><kwd>direct electrical stimulation</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Field A.S., Alexander A.L., Wu Y.C. et al. 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