bluuebunny/crossref_metadata_2025 huggingface dataset:
Studying variation in DWI MRI derived ADC for Prostate Cancer (PCa) with respect to Gleason Grade and location of PCa lesions
Authors: Chatterjee Sudhanya , Shanbhag Dattesh , Mongia Aanchal , Patil Uday , Courot Adele , Gogin Nicolas , Mullick Rakesh
Published: August 2024

Diffusion weighted MRI (DWI) derived apparent diffusion coefficient (ADC) is a marker of the extent of restrictive diffusion in tissues. Higher Gleason Grade (GG) prostate cancer (PCa) lesions are known to exhibit higher restrictive diffusion. In this study we investigated whether ADC as a tissue biomarker follows the known histopathological behavior of PCa lesions by studying variations in ADC with respect to GG of PCa lesions and its location. We observe that ADC values of lesion voxels, although belonging to same GG, vary based on its location.
Deep Learning Assisted Diagnosis of Prostate Cancer: Using a Multi-scale Neural Network Based on Points of Interest
Authors: Huang Weiting , Hou GuoRui , Wang Chen , Ai Kai
Published: August 2024

In this study, we propose a method to predict clinically significant state cancer based on MRI points of interest (POI) and classification network with multi-mode and multi-scale. Instead of the traditional method of manual delineation region-of-interest (ROI) to assist prediction, our method utilizes multi-scale input combined with Spatial Transformer Network (STN) to automatically adjust the adjust the scale of interest. This work also explored the possibility of predicting the grade of prostate cancer in a small amount of data using the method of transfer learning. Experiments show that this method has high prediction performance.
T2 mapping with GRAPPATINI for the characterization of adult-onset and juvenile-onset Huntington Disease
Authors: Caligiuri Maria Eugenia , Bonacci Maria Celeste , Kober Tobias , Zacà Domenico , Squitieri Ferdinando , Quattrone Aldo , Sabatini Umberto
Published: August 2024

T2 mapping is a quantitative MRI technique that may provide further insight regarding the changes that differentially underlie Huntington Disease in two of its clinical forms, adult-onset and juvenile-onset. Here we present pilot evidence that the study of T2 properties of the brain might be of great benefit to the research focused on this rare disease.
Blood-brain barrier permeability changes over the lifespan
Authors: Padrela Beatriz , Sneve Markus , Zelhorst Sanne , Tee Mervin , Mahroo Amnah , Kuijer Joost , Walhovd Kristine , Konstandin Simon , Eickel Klaus , Barkhof Frederik , Hilal Saima , Günther Matthias , Mutsaerts Henk , Petr Jan
Published: August 2024

Blood-brain-barrier (BBB) dysfunction is a hallmark of aging-related disorders, including cerebral small vessel disease and Alzheimer’s disease. An emerging biomarker of BBB dysfunction is time of exchange (Tex) of water across the BBB as measured by multi-echo arterial spin labeling MRI. We evaluated Tex across the age spectrum in 40 adults from two cohorts of healthy controls, and demonstrated that Tex is higher in gray than in white matter, higher in females than in males, and that Tex decreases with age. These findings suggest that BBB permeability changes over the lifespan can be investigated using arterial spin labeling approaches.
Intravoxel incoherent motion diffusion weighted imaging to assess brain microstructure and perfusion in patients with end-stage renal disease
Authors: Wu Xiangxiang , Jiang Zijian , Zheng Jiahui , Jiao Zhuqing , Liu Tongqiang , Dou Weiqiang , Shi Haifeng
Published: August 2024

This study aimed to investigate the clinical value of intravoxel incoherent motion (IVIM) diffusion-weighted imaging in evaluating the brain microstructural and perfusion changes in end-stage renal disease (ESRD) patients. 40 ESRD patients and 30 healthy subjects were recruited in this study and underwent IVIM MRI. The microstructure and perfusion of the brain showed significantly differences in the left frontal lobe, bilateral temporal lobe, left hippocampus, right occipital lobe, represented by IVIM derived parameters of slow apparent diffusion coefficient (ADCslow) and fast apparent diffusion coefficient (ADCfast). Therefore, we concluded that the brain microstructure and perfusion were impaired in ESRD patients.
Investigating the Use of Statins in a Juvenile Photothrombotic Rat Stroke Model
Authors: Sare Daniel , Li Daniel , Kartono Bryan , Waspe Adam , Kassner Andrea
Published: August 2024

Pediatric stroke remains a significant cause of lifelong neurological impairment and morbity. Treatment options and our understanding of stroke evolution in the developing brain, especially beyond the peri- and neonatal period, is still limited. By using a photothrombotic juvenile rat stroke model and quantitative MRI, we were able to assess stroke and blood-brain barrier damage following the use of atorvastatin from the hyper acute to chronic stages following acute ischemic stroke. Findings support a reduction in lesion volume within the statin group with no significant changes to BBB damage.
Prognostic value of myocardial strain after chemotherapy in children with leukemia: a cardiac magnetic resonance study
Authors: Xu Rong , Huang Wei , Liu Lini , zhang Xiaoyong , Guo Yingkun
Published: August 2024

The stage of chemotherapy in children with ALL is a long process, and the myocardial damage caused by chemotherapy is still unknown. The different chemotherapy stages may have different degrees of myocardial damage. In this study, cardiac magnetic resonance was used to evaluate myocardial strain in ALL patients at different stages of treatment, and it was found that myocardial strain reduction was more pronounced in the early stages of treatment, and that global strain was a risk factor for adverse clinical outcomes.
Comprehensive 4D flow MRI analysis of aortic flow hemodynamics in pediatric/young adult patients with bicuspid aortic valve
Authors: Fujiwara Takashi , Malone LaDonna , Jarvis Kelly , Chatfield Kathryn , Browne Lorna , Barker Alex
Published: August 2024

Bicuspid aortic valve is associated with progressive aortic dilatation, which is seen both in pediatric and adult populations. Although several studies have found a connection between aortic hemodynamics, vessel wall architectural abnormalities, and progressive dilation, the role of hemodynamics in pediatric aortopathy remains unclear. We used 4D flow MRI data in pediatric bicuspid aortic valve patients to identify potential hemodynamic biomarkers associated with aortic diameter. Despite no clear association with aortic diameter, different flow features between BAV patients with/without coarctation were found.
Spectrally-encoded multi-spectral imaging (SEMSI) at 0.55T provides improved imaging adjacent to metallic implants
Authors: Li Bochao , Keskin Kübra , Yoon Daehyun , Lee Nam , Hargreaves Brian , Nayak Krishna
Published: August 2024

Spectrally-encoded multi-spectral imaging (SEMSI) enables imaging adjacent to metal implants without blurring due to off-resonance, and has been demonstrated at 3T. Here, we demonstrate application of this technique at 0.55T with appropriate adjustments to the spectral resolution and RF pulse bandwidth. A total hip arthroplasty phantom was imaged with SEMSI, turbo spin echo (TSE), and Slice Encoding for Metal Artifact Correction (SEMAC). Experiments demonstrate the feasibility of SEMSI at 0.55T, and examine ΔTE to support multi-echo acquisitions in a single TR.
A nomogram based on DKI, molecular and clinical risk factors for survival prediction and treatment decision-making in astrocytomas
Authors: Tan Yan , Liu Zeliang , Wang Xiaochun , Zhang Hui
Published: August 2024

To establish a nomogram by integrating DKI, molecular and clinical risk factors for personalized OS estimation in astrocytomas, and explore the nomogram-based treatment benefits. Astrocytomas are the most common brain tumors with poor prognoses. The detection of risk factors may aid in individualizing therapeutic plans and improve survival. It is concluded the nomogram based on DKI, molecular and clinical risk factors could achieve the individualized OS estimation of astrocytomas with excellent performance. For high-risk patients, surgery plus chemo and/or radiotherapy were recommended; while for low-risk patients, additional chemo and/or radiotherapy did not increase survival benefits.
mpMRI Radiomic Features Predict the Likelihood for Progression to Treatment of Prostate Cancer Patients on Active Surveillance
Authors: Wallaengen Veronica , Zacharaki Evangelia , Alhusseini Mohammad , Soodana-Prakash Nachiketh , Algohary Ahmad , Breto Adrian , Xu Isaac , Gaston Sandra , Acosta Rosa Castillo , Kryvenko Oleksandr , Nahar Bruno , Parekh Dipen , Pollack Alan , Punnen Sanoj , Stoyanova Radka
Published: August 2024

Active surveillance (AS) for prostate cancer has emerged as a safe and attractive alternative to immediate treatment. Here we present an integrated method for baseline mpMRI analysis enabling early detection of patients harboring lesions with a high potential for progression. The approach consists of three steps: (i) Training a deep learning network for automatic segmentation of prostate and lesions, suspicious for cancer; (ii) Application of the network to identify lesions on mpMRI images for patients, enrolled in an AS trial; and (iii) Development of a progression risk stratification model by incorporating radiomic and clinical variables.
Nosological images of brain tumor MV-MRS 3T data based on classifiers trained with SV-MRS 1.5T data, a proof-of-concept
Authors: Ungan Gulnur , Pons-Escoda Albert , Ulinic Daniel , Arus Carles , Vellido Alfredo , Julia-Sape Margarida
Published: August 2024

We used SV-MRS 1.5T data of patients with brain tumors to create colored-classification images of MV-MRS 3T grids of an independent cohort of patients. In 10 out of 15 MV cases the solid tumor region corresponded to the correct class. In the remaining 5 cases, the reasons for (partial) misclassification included heterogeneity and bad spectral quality.
Mapping the Accuracy of Diffusion Weighted Imaging Near Total Hip Implants
Authors: Neri John , Koff Matthew , Koch Kevin , Tan Ek
Published: August 2024

Multi-acquisition with variable resonance image combination (MAVRIC) with DWI can reduce artifacts associated with metal implants to characterize synovial reactions near total hip replacements. The purpose of this study was to evaluate the quantitative accuracy of DWI-MAVRIC near actual hip arthroplasty components and demonstrate the feasibility of spatially mapping ADC biases. DWI-EPI and DWI-MAVRIC images were acquired using a diffusion phantom in the presence of femoral heads of different material composition. It was found that cobalt-chromium femoral heads cause more ADC error than oxinium femoral heads. Spatial mapping of ADC accuracy near total hip implants was found to be feasible.
Snapshot CEST at 3T using 3D True FISP
Authors: Wu Yupeng , Wang Zhichao , Pang Qifan , Li Gaiying , Chen Mengying , Yan Xu , Fu Caixia , Song Yang , Li Jianqi
Published: August 2024

For clinical implementation, chemical exchange saturation transfer (CEST) imaging must be fast with high signal‐to‐noise ratio (SNR), 3D coverage, and produce robust contrast. In general, CEST imaging with fast low angle shot GRE sequence (FLASH) can achieve fast acquisition, but may yield low SNR efficiency. This study evaluated APT and NOE maps for single saturation 3D CEST imaging with True FISP and FLASH sequences, respectively. We found that True FISP could achieve better SNR of Z-spectrum and obtain more reliable CEST effects contrast. 3D True FISP sequence is expected to become a more promising 3D CEST-GRE sequence for clinical application.
Effects of Nucleus Pulposus Tissue Hydration on T1ρ and T2 Relaxation Times and Mechanical Properties
Authors: Co Megan , Raterman Brian , Kolipaka Arunark , Walter Benjamin
Published: August 2024

T1ρ and T2 mapping have been developed to quantitively assess intervertebral disc (IVD) degeneration by quantifying proteoglycan and water content, respectively. In addition, magnetic resonance elastography (MRE) has been validated to quantify shear stiffness. This study determines how water content affects MRI relaxation times and MRE-derived mechanical properties. Our results showed that hydration has an influence on T1ρ and T2 relaxation times and MRE-derived shear stiffnesses and that there is a correlation between relaxation times and shear stiffnesses. This highlights MRI as a non-invasive technique to quantify tissue composition and mechanical properties to assess degenerative changes within the IVD.
To trigger or not to trigger – removing cardiac triggering in diffusion MRI of the cervical spinal cord saves time without sacrificing quality
Authors: Schilling Kurt , O'Grady Kristin , Combes Anna , Sweeney Grace , Prock Logan , Adad Julien Cohen , Landman Bennett , Smith Seth
Published: August 2024

Cardiac triggering is commonly used in diffusion MRI protocols of the cervical spinal cord to reduce cardiac-related motion. However, this dramatically increases scan time and can limit high angular resolution multi-shell experiments. We test whether advances in preprocessing motion correction and fitting procedures may overcome cardiac-related motion artifacts. We find that removing cardiac triggering regains significant scan time with no increase in prevalence of artifacts, while providing similar quantitative indices with comparable reproducibility. In summary, removing cardiac triggering for cervical spinal cord diffusion saves time without sacrificing image quality.
R2* Estimation by Multispectral Fat-Water Models for GRE and UTE Acquisitions Using Virtual Liver Iron Overload Model and Monte Carlo Simulations
Authors: Neupane Prasiddhi , Shrestha Utsav , Tipirneni-Sajja Aaryani
Published: August 2024

Multispectral fat-water-R2* models are used for the confounder-free assessment of hepatic iron overload. In this study, Monte Carlo-based virtual liver iron overload models were created, MRI signals were synthesized for GRE and UTE acquisitions, and the R2* values estimated using the monoexponential and the multispectral fat-water models were analyzed. Our results demonstrate that both multispectral models exhibit high accuracy and precision for UTE acquisition at both 1.5T and 3T.
Prediction of Histopathological Subtypes of Dermatofibrosarcoma protuberans Based on MRI Radiomics Machine Learning Model
Authors: Liu Siyu , Wang Yishi , Ai Songtao
Published: August 2024

Dermatofibrosarcoma protuberans (DFSP) is a rare low to intermediate grade soft tissue sarcoma of skin, but the fibrosarcomatous DFSP (FS-DFSP) is a clearly malignant pathological subtype. The identification of malignant pathological subtypes by radiomics plays an important role preoperatively. The non-invasive machine learning method based on T1WI and FS-T2WI imaging is potential prognostic tool by distinguishing different levels of DFSP pathological subtypes before operation in this study to provide a new idea for the diagnosis and treatment of DFSP.
Vascular architecture mapping reveals distinct microvascular profiles in healthy grey and white matter
Authors: Hohmann Anja , Zhang Ke , Mooshage Christoph , Jende Johann , Rotkopf Lukas , Schlemmer Heinz-Peter , Bendszus Martin , Wick Wolfgang , Kurz Felix
Published: August 2024

Vessel architecture mapping (VAM) is a quantitative MR imaging technique based on dynamic changes in gradient-echo (R2*) and spin-echo (R2) relaxation rates during contrast agent administration, that can characterize cerebral blood vessel microstructure and their changes in vivo. We aimed to establish VAM parameter reference ranges in healthy brain tissue by scanning n=135 patients with whole-brain high resolution VAM at 3.0 Tesla MRI. Subsequent analysis revealed distinct microvascular profiles for cortical gray matter, supratentorial white matter and examined subcortical nuclei. These reference values may serve as a starting point for future VAM studies on cerebrovascular pathologies.
Differentiation of tumor-infiltrated edema and pure vasogenic edema in patients with brain tumors by using a fractional order calculus model
Authors: Zhang Qinyuan , Li Jianing , Su Yun , Yan Zhuoheng , Hu Zhixuan , Zeng Weike , Wang Mengzhu , Yan Xu , Mao Jiaji , Shen Jun
Published: August 2024

A fractional order calculus model (FROC) holds promise in differentiating tumor-infiltrated edema from pure vasogenic edema of brain tumors. This study used a q-space Cartesian grid sampling scheme, diffusion spectrum imaging, in patients with high-grade gliomas, meningiomas and brain metastases to generate FROC-based parameters, including D, β and μ. The μ showed the best individual parameter performance in differentiating tumor-infiltrated edema from pure vasogenic edema.
Echo-Volume Imaging with Restricted Field-of-View and (k, t)-Space Undersampling: A Fast fMRI Acquisition Technique
Authors: Luo Qingfei , Sun Kaibao , Dan Guangyu , Karaman Muge , Zhou Xiaohong
Published: August 2024

Echo-volume imaging (EVI) can offer higher acquisition speed than echo-planar imaging (EPI) but is more sensitive to image distortion and blurring. In this study, we develop an EVI-based fast fMRI acquisition technique by employing three-dimension restricted field-of-view imaging (k-t rFOV-EVI) and (k, t)-space undersampling. Our human fMRI experiments covering the visual cortex demonstrate that k-t rFOV-EVI can provide higher image quality and fMRI detection sensitivity than the simultaneous multi-slice EPI at 2.5-mm-isotropic spatial resolution with a temporal resolution of 240 ms.
MRI Radiomics Signature to Predict Lymph Node Metastasis after Neoadjuvant Chemoradiation Therapy in locally advanced Rectal Cancer
Authors: Fang Zhu , Pu Hong , Chen Xiaoli , Yuan Yi , Zhang Feng , Li Hang
Published: August 2024

To develop and validate clinical-radiomics models for predicting lymph node metastasis following neoadjuvant chemoradiation therapy in locally advanced rectal cancer .83 patients were retrospectively enrolled.pre-,post- and delta radiomics signatures of T2WI and ADC images were constructed by support vector machine model. These models were applied to predict LNM and 5-year disease-free survival. The clinical-deltaADC radiomics combined model presented good performance for predicting post-CRT LNM in the training cohort (AUC=0.895) and validation cohort (AUC=0.900). In ypT0-T2 stage, this model could predict 5-year RFS. Clinical-deltaADC radiomics combined model has good performance to predict LNM after nCRT and helped identify patients with poor prognosis.
Radiomics Applied to Phase Contrast MRI Images Successfully Distinguishes Healthy Subjects and Multiple Sclerosis Patients
Authors: Montin Eros , Muccio Marco , Ge Yulin , Lattanzi Riccardo
Published: August 2024

In this study, we applied imaged-based radiomic techniques to phase contrast (PC) MRI images to distinguish the blood flow through the neck-feeding arteries of healthy controls (HC) from MS patients. By applying a simple machine learning model, k nearest neighbor, we found that first order features of the arteries’ regions of interest (ROI), drawn on phase images, reported the best accuracy (0.80) in labeling MS patients and HCs. PC-MRI is a fast and reliable imaging technique that, in conjunction with radiomics, offers great clinical potential to further quantify the diagnosis of MS, currently relying on qualitative approaches.
Automated Deep Learning Segmentation of Human Knee Cartilage from 3T MRI with Boundary Information
Authors: Hu Zhisen , Lally Peter , Bangerter Neal
Published: August 2024

Knee Osteoarthritis (OA) is serious and prevalent today. Image segmentation of high-resolution MRI scans measuring cartilage volume and thickness is useful to track knee OA progression in the early stages and avoid joint replacement. In this work, we developed a cheap and efficient automated technique based on U-Net for knee cartilage segmentation, paying more attention to boundary information. Our model outperforms many existing models for segmentation of the femoral cartilage and performs as well as other techniques for other cartilage compartments. The boundary loss appears to improve cartilage segmentation for the edge slices with smaller cartilage volume.
Examination of the optimal imaging parameters for intracranial vessel wall bone-like imaging using FRACTURE
Authors: Fukushima Keita , Gomyo Miho , Tsuchiya Kazuhiro , Saito Shun , Yoshioka Tatsuya , Arai Takahiro , Yonaha Takayuki , Negishi Ayaka , Sakaguchi Kosuke , Kumagai Yuma , Obara Makoto , Honda Masatoshi , Namiki Takashi , Nishimura Yoshiyuki , Nakanishi Akihito , Yokoyama Kenichi
Published: August 2024

Fast field echo resembling a CT using restricted echo-spacing (FRACTURE), which has been recently developed, has enabled visualization of calcification as well as cortical and spongy bones. However, it cannot be applied to intracranial vessel wall imaging due to insufficient suppression of cerebrospinal fluid (CSF) signal and intra-arterial flow artifact. In this study, by performing scans of an original phantom and healthy volunteers, we reveal that the application of multi-chunk and magnetization transfer contrast pulse to FRACTURE can suppress CSF signal and intra-arterial flow artifact and that FRACTURE can be efficiently applied to vessel wall bone-like imaging.
Increased pulsatility is associated with higher blood flow in the cerebral microvasculature as assessed with 7T MRI
Authors: Elschot Elles , van den Kerkhof Marieke , van der Thiel Merel , van Oostenbrugge Robert , Kroon Abraham , Backes Walter , Jansen Jacobus
Published: August 2024

We studied blood flow pulsatility and perfusion in the cerebral microvasculature to increase the understanding of the pathophysiological processes in hypertension. By exploiting the possibilities of ultra-high-field strength (7T), utilizing phase contrast MRI and spin-echo dynamic susceptibility MRI, we focused specifically on the microvasculature. We found that a higher blood flow pulsatility in the lenticulostriate arteries is correlated with higher cerebral blood flow. Furthermore, hypertension status seems to have an effect on varying pulsatility, which seems to be counteracted by medication usage.
Cerebrovascular reactivity differences in the anterior and posterior brain circulations in Healthy individuals
Authors: Levine Harrison , Poublanc Julien , Sayin Ece , Duffin James , Sobczyk Olivia , Fisher Joseph , Mikulis David
Published: August 2024

There is no consensus regarding the differences in Cerebrovascular Reactivity (CVR) magnitude differences between anterior and posterior circulations in healthy individuals. Forty-four healthy individuals underwent BOLD fMRI using a standardized blood vascular stress test achieved with sequential gas delivery. These results showed that cerebrovascular magnitude and speed of response tau) were stronger and faster in the posterior circulation compared to anterior circulation tissues. Therefore, the knowledge that there are significant regional differences in CVR is critical for investigating the regional impact of cerebrovascular pathologies.
Indirect detection of deuterated glucose brain metabolism at 3 Tesla: preliminary findings in volunteers and patients with gliomas
Authors: Autry Adam , LaFontaine Marisa , Villanueva-Meyer Javier , Chang Susan , de Feyter Henk , Li Yan
Published: August 2024

This study aimed to perform indirect detection of deuterated glucose metabolism at 3 Tesla in healthy subjects and patients with brain tumors using time-series data acquired from atlas-based single-voxel spectroscopy and whole-brain 3D magnetic resonance spectroscopic imaging (MRSI). Following 2H-glucose consumption, subjects generally displayed reduced levels of glutamate in the anterior cingulate cortex (ACC) and midline gray matter, while patient T2 lesions did not appear to show the same trend. These preliminary data demonstrate the ability to detect deuterated glucose metabolism at 3 Tesla.
Apparent Diffusion Coefficient in Breast MRI
Authors: Loubrie Stephane , Andreassen Maren , Rodriguez-Soto Ana , Carl Michael , Batasin Summer , Conlin Christopher , Seibert Tyler , Hahn Michael , Kuperman Joshua , Dale Anders , Rakow-Penner Rebecca
Published: August 2024

Diffusion weighted Imaging (DWI) acquisitions are often part of breast cancer MRI protocols. The signal intensity decrease as a function of the b-value in diffusion imaging is non-linear and complex with inconsistent Apparent Diffusion Coefficients. In this abstract, we investigate ADC mapping computation and accuracy. Mapping techniques gave similar performances, with comparable medians and standard deviations.
Differentiating Benign from Malignant Breast Lesions and Molecular Subtypes Using MRI with a Continuous-Time Random-Walk Diffusion Model
Authors: Chang Huan , Wang Dawei , Li Yuting , Xiang Shaoxin , Xue Ke , Kong Peng , Zeng Qingshi
Published: August 2024

Accurately differentiating breast cancer is crucial for clinical treatment. However, it is challenging due to the high heterogeneity of breast cancer. This study used a continuous-time random-walk (CTRW) diffusion model to characterize breast lesions and their molecular subtypes. The malignant lesions had significantly lower ADC, Dm, and α values than benign lesions. Significant differences were also found between luminal A and triple-negative groups in parameter β. And the combination of CTRW parameters yielded better performance in classifying breast cancer than ADC. Therefore, this study highlights that the CTRW parameters are superior to ADC in distinguishing breast lesions and molecular subtypes.
Predicting Molecular Subtypes and Prognostic Factors of Breast Cancer Using Integrated Diffusion MRI
Authors: Karaman Muge , Bu Yangyang , Dan Guangyu , Zhong Zheng , Luo Qingfei , Wang Shiwei , Zhou Changyu , Hu Weihong , Zhou X. , Xu Maosheng
Published: August 2024

Breast cancer exhibits a wide spectrum of molecular subtypes and, which has important implications in treatment strategies. In this study, we used an integrated diffusion-weighted imaging approach for simultaneous assessment of tissue cellularity, vascularity, and heterogeneity – DISMANTLE – to predict molecular subtypes and prognostic factors of breast cancer. We investigated the feasibility of using the histogram features of the cellularity-, vascularity-, and heterogeneity-related parameters of DISMANTLE for differentiation between luminal-A and luminal-B and HER2+ and HER2- breast cancer.
Investigating border zone hemodynamics with time-encoded super-selective pCASL in internal carotid and basilar artery perfusion territories
Authors: Vaclavu Lena , van Osch Matthias
Published: August 2024

The borders between cerebral perfusion territories are regions of the brain that are susceptible to infarction. In this study, time-encoded super-selective pCASL was implemented to study the hemodynamic properties of the border zones between the left internal carotid artery and basilar artery perfusion territories. Perfusion territories were well-defined with little-to-no detectable overlap. The longest arrival times were found at the border zones, compared to 'inland' of the perfusion region. Combining time-encoded with super-selective pCASL enables the simultaneous investigation of border zones and their arrival times.
Microvascular specificity in velocity-selective arterial spin labeling: Effects of the post-labeling delay
Authors: Barnes Ryan , Chen Conan , Wong Eric , Liu Thomas , Bolar Divya
Published: August 2024

Velocity-selective ASL labels arterial blood spins close to the microvasculature if a sufficiently low velocity cutoff (Vcut) is used. Lowering Vcut, however, introduces diffusion and eddy current effects that confound the CBF measurement. A Vcut of 2 cm/s is typical to minimize these effects, but labels blood slightly upstream from the microvasculature; in this scenario, a non-zero post-labeling delay (PLD) allows time for additional microvascular delivery. We evaluate microvascular specificity (using the spatial coefficient of variation of CBF) as a function of PLD. We find that macrovascular specificity increases with PLD up to around 500ms for a typical ASL resolution.
Evaluation of the peripheral nerves of the knee using Double-Echo Steady-State MRI at 7T
Authors: Chen Pinzhen , Zhen Zhiming , Yin Ting , Chen Wei
Published: August 2024

This study investigated the feasibility of DESS sequence to assess the knee peripheral nerve structures in healthy subjects and patients. The results showed that the nerve imaging quality of DESS sequence was superior to PD sequence in healthy adults. Further, only the isotropic 3D-DESS protocol could clearly visualize the distal peroneal nerve branches and their anatomical course. In patient with peripheral nerves damages, combining the PD and DESS imaging could provide more pathological and anatomical information about the knee peripheral nerve. This suggests that DESS sequence can reliably image the knee peripheral nerves and effectively provide precise knowledge about it.
Feasibility of muscle template creation using tensor based registration
Authors: Froeling Martijn
Published: August 2024

In this study, the aim is to show the feasibility of generating a per-muscle architecture template using a combination of muscle shape and muscle tensor registration. Additionally, the use of a generalized muscle template to identify between-subject differences will be explored. The tensor-based registration does allow for better alignment of internal muscle structures which is not possible using registration based on distance maps alone.
T1rho Dispersion in Proteoglycan-depleted Swine Spine Disc
Authors: Christiansen Mitchell , Preul Mark , Marsh Steven , Turner Jay , Uribe Juan , Nadeem Muhammad , Mufson Elliott , Dortch Richard , Gore John , Wang Ping
Published: August 2024

T1rho imaging has been used to probe relatively slow macromolecular processes, making it a practical tool to gain information about water spin dynamics and interactions with endogenous macromolecules. We measured the dispersion of T1rho with different spin-lock fields in the intervertebral disc of swine spine specimens before and after the treatment to induce proteoglycan loss, a sign of early disc degeneration. Analysis revealed elevated T1rho values in all proteoglycan-depleted discs at each spin-lock field, and that post-treatment T1rho changes increase at a higher spin-lock field.
Deep Learning Reconstructed T2-weighted Dixon Imaging of the Spine: Impact on Acquisition Time and Diagnostic Performance
Authors: Diallo Thierno , Berkarda Zeynep , Wiedemann Simon , Wilpert Caroline , Strecker Ralph , Koerzdorfer Gregor , Nickel Dominik , Bamberg Fabian , Benndorf Matthias , Weiß Jakob
Published: August 2024

Magnetic resonance imaging of the spine is considered one of the most commonly performed examinations in clinical routine. The raising demand for high quality imaging of the spine creates the need for tailored examination protocols, especially with regard to increasingly limited scanner capacities. Deep Learning based imaging reconstruction has emerged as promising novel technique to accelerate MR imaging while maintaining image quality. This study analyzed a novel deep learning accelerated T2-weighted Dixon sequence of the spine in terms of diagnostic performance. The results suggest that the here presented sequence is feasible with a diagnostic performance comparable to standard imaging.
Lumbar spine disc degeneration assessed by in vivo 3T multifrequency MR elastography
Authors: Reiter Rolf , Kaufmann David , Shahryari Mehrgan , Jahn Janosch , Strehle Rebecca , Bayerl Christian , Hamm Bernd , Braun Jürgen , Sack Ingolf , Asbach Patrick
Published: August 2024

Despite the success in detecting intervertebral disc degeneration with high-resolution T2 sequences, conventional MRI is limited by large inter-reader variability as well as lacking stratification of clinical trials and their assessment of treatment responses. Several studies have shown the technical feasibility of MR elastography for the study of the intervertebral disc, but its clinical relevance remains unclear. This study shows an excellent diagnostic performance of high-resolution multifrequency MR elastography in the evaluation of lumbar spine intervertebral disc degeneration.
White matter tracts of MS patients with progression independent of relapse activity show DTI-alterations compared to clinically stable patients
Authors: Ocampo-Pineda Mario , Cagol Alessandro , Barakovic Muhamed , Lu Po-Jui , Müller Jannis , Schaedelin Sabine , Benkert Pascal , Weigel Matthias , Melie-Garcia Lester , Kuhle Jens , Kappos Ludwig , Granziera Cristina
Published: August 2024

Progression independent of relapse activity (PIRA) has been described in patients with multiple sclerosis (MS) even in the earliest disease stages. Patients with PIRA show increased atrophy rates in multiple brain regions compared to stable patients. Here, we investigated whether patients with PIRA exhibit loss of integrity in WM tracts compared to stable patients. We studied 62 RRMS patients, 27 PIRA and 35 stable patients using a clinical DW-MRI protocol. Our results showed that PIRA patients present smaller FA values in areas of corpus callosum and along corticosprinal tract. These differences suggest neurodegeneration in major WM tracts of PIRA patients.
Diffusion tensor imaging study of white matter differences between autoimmune encephalitis and viral encephalitis
Authors: Li Qingrui , Gong Xiarong , Bi Qiu , Wu Yunzhu , Wu Kunhua
Published: August 2024

In this study, diffusion tensor imaging (DTI) analysis based on Tract-based spatial statistics (TBSS) was used to investigate the microstructural changes of white matter (WM) in viral encephalitis (VE) and autoimmune encephalitis (AE). The study found that WM injury degree in patients with VE and AE was different. The DTI parameters can separate AE, VE and healthy control group. The study results indicate that DTI could serve the function of early diagnosing and distinguishing AE from VE, and provide imaging evidence for the pathophysiological changes of WM in AE and VE patients.
Preserved white matter integrity despite changes in brain structure and metabolism in mouse with lethal irradiation and bone marrow transplant
Authors: Cui Min-Hui , Fleysher Roman , Torres Lidiane , Ambadipudi Kamalakar , Branch Craig
Published: August 2024

Adult cells from transplanted bone marrow can generate new neurons in central nervous system (CNS) in rodent and human. Here we report for the first time in live mouse that white matter integrity in lethally irradiated mouse transplanted with adult mouse bone marrow (BMTX) is preserved, reflected in increased fractional anisotropy (FA) of corpus callosum post BMTX. Stable concentration of N-acetyl-aspartate (NAA) and increased FA after BMTX suggests that donor cells along with irradiation may stimulate new neuronal proliferation. Nevertheless, decreased myo-inositol concentration may reflect its cell volume regulation function as seen in morphometric adjustments in BMTX brains.
Myelin water fraction mapping using relaxation spectra from steady-state gradient echo imaging with partial RF spoiling
Authors: Stöcker Tony , Stirnberg Rüdiger , Wang Difei , Ehses Philipp , Pracht Eberhard
Published: August 2024

A new approach for myelin water fraction (MWF) mapping is presented, based on gradient echo signals with small RF spoiling phase increments. Partially spoiled gradient echo data with 20 different phase increments ($$$|\Delta\phi|\le20^\circ$$$) were efficiently acquired with a custom skipped-CAIPI 3D-EPI sequence. The data is well-suited for a novel joint-fitting approach of $$$T_1$$$- and $$$T_2$$$-spectra, from which high-quality whole-brain MWF maps are derived. MWF-maps show qualitatively good agreement with published data in the white matter (WM). Additionally, the approach seems to provide robust estimates in regions with small MWF, such as the gray matter (GM).
Myelin Water Atlas Template derived from Quantitative Parameter Mapping
Authors: Kanazawa Yuki , Kitano Shun , Harada Masafumi , Taniguchi Yo , Matsumoto Yuki , Hayashi Hiroaki , ito Kosuke , Bito Yoshitaka , Haga Akihiro
Published: August 2024

We generated a myelin water atlas template derived from QPM. Imaging data were acquired using a multi-gradient-echo sequence for QPM. All the data in the 48 white matter regions measured in the volume-of-interest were plotted, and quadratic polynomial equations of each region were derived from the relationship between R1·R2* and the two-component model-MWF. As a result, the relationship between R1·R2* and MWF showed a strong significant correlation for all of the white matter regions (R2 ≥ 0.963, P < 0.0001). Our myelin water atlas template derived from QPM can be used as a reference to demonstrate areas of demyelinating disease.
Two clinically feasible myelin water imaging methods (MCR-DIMWI and METRICS) can differentiate patients with a leukodystrophy from controls.
Authors: Stellingwerff Menno , Al-Saady Murtadha , Chan Kwok-Shing , Dvorak Adam , Marques José , Kolind Shannon , van der Knaap Marjo , Pouwels Petra
Published: August 2024

Imaging biomarkers are needed for studying white matter (WM) diseases. Myelin water imaging (MWI) uses multi-compartment relaxometry to estimate myelin content, and is promising for use in leukodystrophies. We applied MCR-DIMWI and METRICS, two novel whole-brain MWI techniques, to a cohort of 9 leukodystrophy patients and 15 controls. Myelin water fractions (MWFs) from both techniques correlated well. In patients, MWF was decreased. For both techniques region-specific MWFs and relaxation metrics could differentiate patients from controls. They are promising for use in the context of leukodystrophies; additional studies are required to further explore potential clinical application.
Iron deficiency anemia is associated with abnormal cerebral metabolic rate, blood brain barrier permeability and cognitive function.
Authors: Suriany Silvie , Gonzalez-Zacarias Clio , Vu Chau , ONeil Sharon , Mathur Gagan , Ward Dawn , Ziman Alyssa , Klapper Ellen , Zhuang Lefan , Wood John
Published: August 2024

Iron deficiency is the predominant cause of anemia in adults, typically occurring in women with heavy menses, endometriosis or fibroids. We study cerebral metabolic rate of oxygen (CMRO2), blood brain barrier (BBB) permeability to water, and neurocognitive function in 34 women with iron deficiency anemia (IDA). We observed striking deficits in verbal and spatial memory, perceptual reasoning, and crystalized intelligence that were strongly correlated with hemoglobin level. CMRO2 was lower than predicted by anemia alone, correlated to BBB permeability to water, and associated with poorer neurocognitive performance, suggesting decreased brain capillary surface area for oxygen and water diffusion.
Assessing inter-tract independence across microstructural metrics
Authors: McNabb Carolyn , Messaritaki Eirini , Koller Kristin , Jones Derek
Published: August 2024

We aimed to identify potential redundancies in microstructural measures between major white matter tracts and asked which microstructural metrics correlate most within a tract. Using a combination of microstructural imaging techniques, including diffusion imaging, relaxometry and quantitative magnetisation transfer imaging, we identified strong correlations between homologous left and right fasciculi in the cingulum bundles, inferior longitudinal fasciculi, uncinate fasciculi and arcuate fasciculi as well as similar patterns of tissue microstructure between heterologous tracts. However, corticospinal tracts showed weak correlations with other tracts and a unique pattern of inter-metric correlations, suggesting that summarising metrics across all tracts would be inappropriate.
Measuring structural connectivity in migraine: the impact of correcting for region volumes
Authors: Matoso Ana , Fouto Ana , Ruiz-Tagle A. , Esteves I. , Caetano Gina , Silva Nuno , Vilela Pedro , Gil-Gouveia Raquel , Figueiredo Patrícia , Nunes Rita
Published: August 2024

When studying structural brain connectivity, there are many normalization strategies that can be employed, however, there is still no consensus on which one is best to use. Hence, in this study, we investigated the impact of normalizing by the region volumes in the context of migraine as this is sometimes done to avoid bias towards higher connectivity in bigger regions. Several metrics showed significant differences between normalization strategies and, more critically, nodal metrics displayed different behaviours when compared between controls and migraineurs.
An open-source, low-cost 8-channel transmit/receive 3T head coil for pTx developments, MR safety testing and standardization
Authors: Aigner Christoph , Vinding Mads , Winter Lukas , Montag Reiner , Schmitter Sebastian , Ittermann Bernd , Seifert Frank
Published: August 2024

This work investigates an open-source, low-cost 8-channel transmit/receive head coil to enable rapid and reproducible pTx development, safety assessment and evaluation at 3T. FDTD simulations were validated with phantom measurements on a 3T with an external pTx system. Relative and absolute 2D/3D B1+-maps were acquired to compute the CP+ mode, and two RF shims were tailored to enforce B1+ efficiency and homogeneity. The open-access design files could serve as a basis for new RF coil designs or pTx projects without needing high expertise in RF coil development or as a cost-effective alternative for multi-centre studies.
SAR and Temperature Safety Assessment on Patient Specific Models Generated with a Registration Method
Authors: Carluccio Giuseppe , Montin Eros , Collins Christopher , Lattanzi Riccardo
Published: August 2024

Patient specific models are required to improve the accuracy of the simulations to perform safety assessment related to interaction of the RF fields with the body tissues. One registration method allows non-rigid transformations: this can be used to reshape a numerical body model to match the images of a patient, and generate a model similar to the shape of the patient. We performed SAR and temperature simulations to evaluate the ability of the registered model to perform a patient-specific safety assessment. The evaluation has been successful: the SAR and temperature patterns were corresponding to the ones of the target anatomy.
SAR Simulations with a Poseable Numerical Body Model for 3T MRI of Straight & Flexed Knee: First Results
Authors: Brantner Douglas , Collins Christopher
Published: August 2024

Although recent developments in flexible coils have allowed for imaging of the knee in a flexed or straight position, simulations for safety assessment are typically performed with both legs straight. Here we show first results of SAR simulations with both legs straight versus knee flexed with fields normalized as if imaging the knee that is changing position. Results indicate a decrease in maximum 10g SAR when the knee being imaged is flexed.
Statistical evaluation of complexity tests for fMRI timeseries data
Authors: Wijesinghe Dilmini , Wang Danny , Jann Kay
Published: August 2024

Complexity measures of rs-fMRI signals based on non-linear timeseries analyses have been proposed for quantifying the predictability of fMRI signals. There are multiple mathematical methods for evaluating complexity in timeseries signals. This study evaluates the optimal parameter settings in seven complexity tests by analyzing mean complexity measures of grey matter (GM) and CSF across multiple complexity tests with different parameter settings and different fMRI acquisition protocols. Furthermore, complexity evaluation was performed on surrogate timeseries data. Overall, Multiscale Sample Entropy, Fuzzy Entropy, and Hurst Exponent consistently showed an increase in mean complexity of GM compared to CSF in original data.
Joint Slice-Selective Pulse Design for Segmented FLEET-EPI using a Differential Bloch Simulator and Conjugate Gradient-Optimal Control
Authors: Shaik Imam Ahmed , Balasubramanian Mukund , Berman Avery J.L. , Polimeni Jonathan R. , Grissom William
Published: August 2024

Multishot EPI-based fMRI can achieve high spatial resolutions to resolve functional activity at the level of layers and columns, but suffers sensitivity to motion and phase changes between shots. Reordering the shots in a multislice stack so that each slice’s shots are acquired sequentially (VFA-FLEET-EPI) reduces this sensitivity but requires specialized RF pulses to maintain consistent signal between shots as longitudinal magnetization evolves. In this work we show that designing these pulses jointly using an autodiff optimal control algorithm yields more consistent signal across shots which reduces ghosting compared to VFA sinc and recursively designed SLR pulses.
Quantitative calculation of breast density with proton density fat fraction enables distinction between latest subjective BI-RADS categories
Authors: Gordon Isobel , Ralli George , Herlihy Amy , Fernandes Carolina , O'Brien Amy , Collins Sally , Brady Michael
Published: August 2024

Breast density is a well-established risk factor for breast cancer but conventional visual assessment using mammography has high operator variability. Proton density fat fraction (PDFF) derived from chemical shift encoded (CSE)-MRI has recently been proposed as a quantitative, non-ionising, operator-independent tool for the calculation of breast density. This study demonstrates that breast density derived from PDFF maps which account for a breast-specific fat spectrum can distinguish between the latest density categorisations used in clinical practise and thereby may have use in cancer risk assessment and as a determinant of clinical pathways.
Realistic Digital Reference Object (DRO) toolkit for quantitative breast Ultra-Fast Dynamic Contrast-Enhanced (UF-DCE) MRI
Authors: Bae Jonghyun , Tan Zhengguo , Huang Zhengnan , Heacock Laura , Moy Linda , Knoll Florian , Kim Sungheon
Published: August 2024

Reconstruction of highly accelerated dynamic images is challenging and requires rigorous validation of reconstruction methods. We proposed a digital reference object (DRO) toolkit that provides realistic morphology and contrast dynamics in breast cancer. We acquired various base images containing real breast cancer lesions and simulated realistic contrast dynamics using the estimated kinetic parameters. Our toolkit provides a large number of reference objects with wide ranges of the dynamic images, kinetic parameters, segmentation masks, and k-space data. These realistic DROs with known ground-truth values can be used for different studies, including validation of reconstruction and training deep neural network.
Efficient 3D cone trajectory design for improved combined angiographic, structural and perfusion imaging using arterial spin labelling
Authors: Shen Qijia , Chiew Mark , Wu Wenchuan , Okell Thomas
Published: August 2024

4D combined angiographic, structural and perfusion radial imaging using arterial spin labelling (CASPRIA) provides a tool to simultaneously acquire information about brain structure and blood flow. However, the radial trajectory used limits the resolution and SNR, especially when the data is highly undersampled. In this work, an optimised 3D cone trajectory is presented with 3D golden means rotation to improve sampling at the k-space periphery whilst maintaining flexibility in spatiotemporal resolution. A locally low rank reconstruction was used to leverage spatiotemporal correlations and improve image quality. In vivo results showed considerable improvements in resolution and SNR over the radial approach.
Whole Brain Distortion-free 3D pseudo-Continuous Arterial Spin Labeling at 7T with Turbo FLASH, Optimized Labeling and Background Suppression
Authors: Zhao Chenyang , Shao Xingfeng , Shou Qinyang , Ma Samantha , Gokyar Sayim , Graf Christina , Stollberger Rudolf , Wang Danny
Published: August 2024

The potential of 7T has not been fulfilled for pseudo-Continuous Arterial Spin Labeling (pCASL) because of challenges in labeling, background suppression (BS), and readouts. This study proposed a new labeling parameter, a superior BS pulse, and an accelerated and segmented 3D Turbo-FLASH (TFL) readouts. Despite the field inhomogeneity at 7T, the new labeling parameter achieves high labeling efficiency without signal interference, and OPTIM as BS pulse robustly achieves high inversion efficiency. 3D TFL pCASL provides whole brain coverage, abundant anatomical information without distortion, high resolution, and sufficient SNR in 11 mins.