Reconstruction of the Corticospinal Tract in Patients with Motor-Eloquent High-Grade Gliomas Using Multilevel Fiber Tractography Combined with Functional Motor Cortex Mapping

BACKGROUND AND PURPOSE: Tractography of the corticospinal tract is paramount to presurgical planning and guidance of intraoperative resection in patients with motor-eloquent gliomas. It is well-known that DTI-based tractography as the most frequently used technique has relevant shortcomings, particularly for resolving complex fiber architecture. The purpose of this study was to evaluate multilevel fiber tractography combined with functional motor cortex mapping in comparison with conventional deterministic tractography algorithms. MATERIALS AND METHODS: Thirty-one patients (mean age, 61.5 [SD, 12.2] years) with motor-eloquent high-grade gliomas underwent MR imaging with DWI (TR/TE ¼ 5000/78 ms, voxel size ¼ 2 × 2 × 2 mm3, 1 volume at b ¼ 0 s/mm2, 32 volumes at b ¼ 1000 s/mm2). DTI, constrained spherical deconvolution, and multilevel fiber tractography–based reconstruction of the corticospinal tract within the tumor-affected hemispheres were performed. The functional motor cortex was enclosed by navigated transcranial magnetic stimulation motor mapping before tumor resection and used for seeding. A range of angular deviation and fractional anisotropy thresholds (for DTI) was tested. RESULTS: For all investigated thresholds, multilevel fiber tractography achieved the highest mean coverage of the motor maps (eg, angular threshold = 60°; multilevel/constrained spherical deconvolution/DTI, 25% anisotropy threshold ¼ 71.8%, 22.6%, and 11.7%) and the most extensive corticospinal tract reconstructions (eg, angular threshold ¼ 60°; multilevel/constrained spherical deconvolution/DTI, 25% anisotropy threshold ¼ 26,485 mm3, 6308 mm3, and 4270 mm3). CONCLUSIONS: Multilevel fiber tractography may improve the coverage of the motor cortex by corticospinal tract fibers compared with conventional deterministic algorithms. Thus, it could provide a more detailed and complete visualization of corticospinal tract architecture, particularly by visualizing fiber trajectories with acute angles that might be of high relevance in patients with gliomas and distorted anatomy.</p

Uterine bleedings and quality of woman's life

12 березня 2019 р. у Києві відбулося засідання Експертної ради з питань впливу маткових кровотеч на якість життя жінки, до роботи якої були залучені провідні вітчизняні та європейські фахівці. Згідно з думкою міжнародних експертів (клінічні рекомендації Національного інституту здоров'я і якості медичної допомоги Великобританії та Міжнародної федерації гінекології та акушерства від 2018 р.), вибір тактики ведення пацієнтки визначається не результатом вимірювання крововтрати, а самопочуттям жінки (дистрес, зниження працездатності, сексуальної активності та якості життя). Менструальні симптоми зазвичай є легкими і незначними або взагалі відсутні за умови, якщо менструальне запалення відповідає наступним трьом критеріям: «завершується» (відновлюється нормальна цитоархітектура тканини, перш за все ендометрія); обмежене в часі; адекватне і достатнє за інтенсивністю для завершення відновлення гістологічних та функціональних характеристик залучених тканин. Однак якщо локальне і системне запалення, асоційоване з менструацією, є надмірним за інтенсивністю і тривалістю, воно викликає різні патологічні симптоми. Тяжкі менструальні симптоми клінічно корелюють з місцевим та системним запаленням, яке не завершується (менструація є надмірною за тривалістю та інтенсивністю). Тому пригнічення менструального запалення є важливим для зменшення частоти проявів та інтенсивності менструальних симптомів і покращення якості життя жінок репродуктивного віку. Для оптимізації фізичного та психічного здоров`я жінкам необхідні належні стабільні рівнів естрогенів та прогестерону. При виборі комбінованих оральних контрацептивів для здорових жінок доцільно віддавати перевагу препаратам із коротким безгормональним інтервалом (24+4, 26+2) у порівнянні з традиційним режимом (21+7). Скорочення цього інтервалу забезпечує більш стабільний рівень естрадіолу, знижує ризик випадкової овуляції в разі пропуску таблеток, підвищує резерв контрацептивної надійності в порівнянні з традиційним режимом, а також дозволяє зменшити частоту появи симптомів, асоційованих з відміною гормонів.On March 12, 2019, an Advisory Board on impact of uterine bleedings on the quality of life of a woman was held in Kyiv, with participation of leading Ukrainian and European experts.According to opinion of international experts (guidelines of the UK National Institute for Health and Care Excellence and the International Federation of Gynecology and Obstetrics from 2018), the choice of patient management tactics is notdetermined by measuring blood loss, but by the patient’s well-being (distress, decrease of work ability, sexual activity and quality of life).Menstrual inflammation is phisiological and menstrual symptoms are usually mild/minor or absent when three criteria are fulfilled: resolving (normal cytoarchitecture of the tissue is reconstructed, endometrium first); limited in time; adequateand sufficient by intensity to finalize the reconstruction to the histological and functional characteristics of the different tissues involved. At the same time, if local and systemic inflammation associated with menstruation is On March 12, 2019, an Advisory Board on impact of uterine bleedings on the quality of life of a woman was held in Kyiv, with participation of leading Ukrainian and European experts.According to opinion of international experts (guidelines of the UK National Institute for Health and Care Excellence and the International Federation of Gynecology and Obstetrics from 2018), the choice of patient management tactics is notdetermined by measuring blood loss, but by the patient’s well-being (distress, decrease of work ability, sexual activity and quality of life).Menstrual inflammation is phisiological and menstrual symptoms are usually mild/minor or absent when three criteria are fulfilled: resolving (normal cytoarchitecture of the tissue is reconstructed, endometrium first); limited in time; adequateand sufficient by intensity to finalize the reconstruction to the histological and functional characteristics of the different tissues involved. At the same time, if local and systemic inflammation associated with menstruation is excessive byintensity and duration, it can cause different pathological symptoms. Severe menstrual symptoms are clinically correlated with local and systemic inflammation, which is not resolving (menstruation is excessive in duration and intensity).Therefore, reducing menstrual inflammation is important to reduce the frequency and intensity of menstrual symptoms and improve the quality of life of women of reproductive age.Women need appropriate stable levels of estrogen and progesterone to optimize their physical and mental health. During combined oral contraceptives selection for healthy women it is reasonable to give preference to contraceptives with shorthormonal free interval (24+4, 26+2) compared to the traditional regimen (21+7), since the reduction of this interval provides a more stable level of estradiol, reduces the risk of casual ovulation in case of missed pill, increases contraceptiveefficacy in comparison with the traditional regimen and reduce the incidence of hormone-withdrawal associated symptoms

Cross-scanner and cross-protocol multi-shell diffusion MRI data harmonization: algorithms and result

Cross-scanner and cross-protocol variability of diffusion magnetic resonance imaging (dMRI) data are known to be major obstacles in multi-site clinical studies since they limit the ability to aggregate dMRI data and derived measures. Computational algorithms that harmonize the data and minimize such variability are critical to reliably combine datasets acquired from different scanners and/or protocols, thus improving the statistical power and sensitivity of multi-site studies. Different computational approaches have been proposed to harmonize diffusion MRI data or remove scanner-specific differences. To date, these methods have mostly been developed for or evaluated on single b-value diffusion MRI data. In this work, we present the evaluation results of 19 algorithms that are developed to harmonize the cross-scanner and cross-protocol variability of multi-shell diffusion MRI using a benchmark database. The proposed algorithms rely on various signal representation approaches and computational tools, such as rotational invariant spherical harmonics, deep neural networks and hybrid biophysical and statistical approaches. The benchmark database consists of data acquired from the same subjects on two scanners with different maximum gradient strength (80 and 300 ​mT/m) and with two protocols. We evaluated the performance of these algorithms for mapping multi-shell diffusion MRI data across scanners and across protocols using several state-of-the-art imaging measures. The results show that data harmonization algorithms can reduce the cross-scanner and cross-protocol variabilities to a similar level as scan-rescan variability using the same scanner and protocol. In particular, the LinearRISH algorithm based on adaptive linear mapping of rotational invariant spherical harmonics features yields the lowest variability for our data in predicting the fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK) and the rotationally invariant spherical harmonic (RISH) features. But other algorithms, such as DIAMOND, SHResNet, DIQT, CMResNet show further improvement in harmonizing the return-to-origin probability (RTOP). The performance of different approaches provides useful guidelines on data harmonization in future multi-site studies

Cross-scanner and cross-protocol multi-shell diffusion MRI data harmonization: algorithms and results

Cross-scanner and cross-protocol variability of diffusion magnetic resonance imaging (dMRI) data are known to be major obstacles in multi-site clinical studies since they limit the ability to aggregate dMRI data and derived measures. Computational algorithms that harmonize the data and minimize such variability are critical to reliably combine datasets acquired from different scanners and/or protocols, thus improving the statistical power and sensitivity of multi-site studies. Different computational approaches have been proposed to harmonize diffusion MRI data or remove scanner-specific differences. To date, these methods have mostly been developed for or evaluated on single b-value diffusion MRI data. In this work, we present the evaluation results of 19 algorithms that are developed to harmonize the cross-scanner and cross-protocol variability of multi-shell diffusion MRI using a benchmark database. The proposed algorithms rely on various signal representation approaches and computational tools, such as rotational invariant spherical harmonics, deep neural networks and hybrid biophysical and statistical approaches. The benchmark database consists of data acquired from the same subjects on two scanners with different maximum gradient strength (80 and 300 mT/m) and with two protocols. We evaluated the performance of these algorithms for mapping multi-shell diffusion MRI data across scanners and across protocols using several state-of-the-art imaging measures. The results show that data harmonization algorithms can reduce the cross-scanner and cross-protocol variabilities to a similar level as scan-rescan variability using the same scanner and protocol. In particular, the LinearRISH algorithm based on adaptive linear mapping of rotational invariant spherical harmonics features yields the lowest variability for our data in predicting the fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK) and the rotationally invariant spherical harmonic (RISH) features. But other algorithms, such as DIAMOND, SHResNet, DIQT, CMResNet show further improvement in harmonizing the return-to-origin probability (RTOP). The performance of different approaches provides useful guidelines on data harmonization in future multi-site studies

Insights from the IronTract challenge: Optimal methods for mapping brain pathways from multi-shell diffusion MRI

Limitations in the accuracy of brain pathways reconstructed by diffusion MRI (dMRI) tractography have received considerable attention. While the technical advances spearheaded by the Human Connectome Project (HCP) led to significant improvements in dMRI data quality, it remains unclear how these data should be analyzed to maximize tractography accuracy. Over a period of two years, we have engaged the dMRI community in the IronTract Challenge, which aims to answer this question by leveraging a unique dataset. Macaque brains that have received both tracer injections and ex vivo dMRI at high spatial and angular resolution allow a comprehensive, quantitative assessment of tractography accuracy on state-of-the-art dMRI acquisition schemes. We find that, when analysis methods are carefully optimized, the HCP scheme can achieve similar accuracy as a more timeconsuming, Cartesian-grid scheme. Importantly, we show that simple pre-and post-processing strategies can improve the accuracy and robustness of many tractography methods. Finally, we find that fiber configurations that go beyond crossing (e.g., fanning, branching) are the most challenging for tractography. The IronTract Challenge remains open and we hope that it can serve as a valuable validation tool for both users and developers of dMRI analysis methods