María del Mar Álvarez-Torres¹, Elies Fuster-Garcia^1,2, Carmen Balaña³, Josep Puig⁴, Gaspar Reynes⁵, Kyrre Eeg Emblem², Enrique Mollà-Olmos⁶, Jose Pineda^7,8, and Juan M García-Gómez^1
1Biomedical Data Science Laboratory. ITACA, Universitat Politècnica de València, Valencia, Spain, ²Oslo University Hospital, Oslo, Norway, ³Institut Catala Oncologia Badalona, Barcelona, Spain, ⁴Institut de Diagnostic per la Image (IDI), Hospital Dr Josep Trueta, Girona, Spain, ⁵Instituto de Investigación Sanitaria La Fe, Valencia, Spain, ⁶Hospital de la Ribera, Alzira, Valencia, Spain, ⁷Hospital Clinic de Barcelona, Barcelona, Spain, ⁸void.space Lab, Facultat de Medicina, Universitat de Vic, Vic, Spain

IDH-wildtype glioblastoma and IDH-mutant astrocytoma are classified as different gliomas according to WHO 2021. IDH mutations are key at clinical level, since they are associated with patient prognosis and seem to be critical for treatment selection. Despite these evidences, current protocols do not include the full sequencing for all tumors. In this sense, non-invasive and automatically calculated MRI-based biomarkers can be helpful for the clinical practice. 

Our results show that perfusion markers obtained in an automated, repeatable, and non-invasive manner may be candidates for being surrogate predictive markers of IDH mutation status in astrocytomas grade 4.

Samuel Bobholz¹, Allison Lowman², Michael Brehler², Savannah Duenweg¹, John Sherman¹, Fitzgerald Kyereme², Elizabeth Cochran³, Dylan Coss³, Jennifer Connelly⁴, Wade Mueller⁵, Mohit Agarwal², Anjishnu Banerjee⁶, and Peter LaViolette^2,7
1Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States, ²Radiology, Medical College of Wisconsin, Milwaukee, WI, United States, ³Pathology, Medical College of Wisconsin, Milwaukee, WI, United States, ⁴Neurology, Medical College of Wisconsin, Milwaukee, WI, United States, ⁵Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, United States, ⁶Biostatistics, Medical College of Wisconsin, Milwaukee, WI, United States, ⁷Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI, United States

This study compared autopsy tissue samples to clinical MRI from glioblastoma (GBM) patients to assess the effects of tumor outside of T1-contrast enhancement and FLAIR hyperintensity on clinical characteristics and outcomes. Non-enhancing tumors were more frequent amongst patients who had a history of bevacizumab treatment and no history of Tumor Treating Fields treatment. Additionally, non-enhancing tumors were associated with shorter overall survival times. These results suggest that non-enhancing tumors have clinically significant correlates and may result in worse survival outcomes for GBM patients. 

Umberto Villani^1,2, Erica Silvestri^1,2, Manuela Moretto^1,2, Maria Colpo^1,2, Alessandro Salvalaggio^1,3, Maurizio Corbetta^1,3,4, Diego Cecchin^1,5, and Alessandra Bertoldo^1,2
1Padova Neuroscience Center, University of Padova, Padova, Italy, ²Department of Information Engineering, University of Padova, Padova, Italy, ³Department of Neuroscience, University of Padova, Padova, Italy, ⁴Venetian Institute of Molecular Medicine, Padova, Italy, ⁵Department of Medicine, Unit of Nuclear Medicine, University of Padova, Padova, Italy

Gliomas are amongst the most common primary brain tumours in adults and are often associated with poor prognosis. Understanding the extent of white matter (WM) which is affected outside the tumoral lesion may be of paramount importance to explain cognitive deficits and the clinical progression of the disease. Thus, we apply both direct (i.e., tractography based) and indirect (i.e., atlas based) approaches to quantifying WM structural disconnections in a cohort of 50 glioma patients. We eventually compare the disconnections maps provided by the two methodologies in terms of spatial similarity and discuss their critical use in this field.

Victoria Y Yu¹, Kathryn R Tringale², Robert Young³, Ricardo Otazo¹, and Ouri Cohen^1
1Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, United States, ²Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, United States, ³Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, United States

Chemical Exchange Saturation Transfer (CEST) imaging is a promising method for cancer imaging and was recently combined with MR fingerprinting (CEST-MRF) for fast quantitative relaxation and exchange mapping. The CEST-MRF parametric maps reflect different biophysical processes, and their combination provides a comprehensive picture of complex pathologies, like brain tumors. The goal of this work is to demonstrate the potential utility of CEST-MRF in imaging brain metastases (BM). The in vivo reproducibility of the method is quantified in a healthy subject and the clinical utility is shown in subjects with metastatic brain tumors.

Yajing Zhang¹, Xiangyu Xiong¹, and Yaou Liu^2
1MR Clinical Science, Philips Healthcare, Suzhou, China, ²Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China

To reduce the exposure of Gadolinium-based Contrast Agents (GBCAs) in brainstem glioma detection and provide high-resolution contrast information, we propose a novel multi-task generative network for contrast-enhanced T1-weight MR synthesis on brainstem glioma images. The proposed network can simultaneously synthesize the high-resolution contrast-enhanced image and the segmentation mask of brainstem glioma lesions.

Gopal Varma¹, Alan T Yeo^2,3, Cody Callahan^1,4, David C Alsop¹, Aaron K Grant¹, and Alain Charest^2,5
1Division of MR Research, Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States, ²Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States, ³Sackler School of Graduate Studies, Tufts University School of Medicine, Boston, MA, United States, ⁴Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States, ⁵Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States

Inhomogeneous MT (ihMT) MRI was applied in a genetic mouse model of glioblastoma to assess its potential to provide useful complementary information regarding the true extent of tumor infiltration. Data were acquired to produce maps of MT and ihMT ratios, which were analyzed based on regions of interest relative to brain tissue contralateral to the tumor and progression with time. The tumor was characterized by significantly lower MT and ihMT. Reduction in peripheral white matter ihMT was taken to indicate demyelinating processes associated with glioblastoma. Thus, ihMT might be used to inform on disease progression in tumor adjacent brain tissue.

Huijun Vicky Liao¹, Raymond Y Huang², Stella K Kang³, and Alexander Lin^1
1Center for Clinical Spectroscopy, Brigham and Women's Hospital, Boston, MA, United States, ²Radiology, Brigham and Women's Hospital, Boston, MA, United States, ³Radiology, NYU Langone Medical Center, New York, NY, United States

Our decision-analytic model examined the cost-effectiveness of MR Spectroscopy (MRS), MR perfusion (MRP), and the combination of MRS, MRP and DWI for differentiating brain radiation necrosis from tumor progression in high-risk low-grade glioma. Our results suggested that performing combined imaging method had good diagnostic accuracy for a 3-year time horizon but not a cost-effective in the long run. In contrast, MRS and especially MRP alone were more cost-effective over all time horizons. MRS is the most cost-effective method in lifetime when its negative predictive value≥88% at the Willingness-to-Pay threshold of $100,000.

Karl Kiser¹, Jin Zhang¹, and Gene Kim^1
1Radiology, Weill Cornell Medical College, New York, NY, United States

The T1 recovery curves of cells may be sensitized to water exchange when suspended in solution with gadolinium-based contrast agent. The non-monoexponential recovery curves are fitted to a two-site exchange model to estimate the water exchange rate. This estimation process requires the inclusion of relevant parameters such as volume mol fraction and intracellular relaxation time, cannot be accurately estimated from a single curve. Here, we propose a multiple curve fitting approach, which infuses the model with additional information. By modelling multiple recovery curves of samples in a titration of GBCAs, we demonstrate an accurate and robust method for measuring invitro water exchange, volume mol fractions and intracellular relaxation rate.
The T1 recovery curves of cells may be sensitized to water exchange across the cell membrane when suspended in solution with gadolinium-based contrast agent. The two-compartment model fitting requires the inclusion of relevant parameters such as volume mol fraction and intracellular relaxation time but cannot be accurately estimated from a single curve. Here, we propose a multiple curve fitting approach, which infuses the model with additional information. By modelling multiple recovery curves of samples in a titration of GBCAs, we demonstrate an accurate and robust method for measuring invitro water exchange, cell volume and intracellular relaxation rate.

Xia Wang¹, Chaoqun Bu#¹, Gang Tian#¹, Zeliu Du¹, Yu Jiang¹, Na Zhao¹, Chanjuan Yu¹, Yuedong Han*¹, Jianguang He¹, Xiuzheng Yue², and Zhiwei Shen^2
1Xi'an Gaoxin Hospital, Xi'an, China, ²Philips Healthcare, Beijing, China

The application of amide proton transfer (APT) weighted imaging in molecular imaging of craniocerebral tumors has been relatively mature, but rarely reports on renal tumors. This study conducted a preliminary comparative analysis of clear cell renal cell carcinoma (ccRCC) and healthy adult renal APT imaging. The APTw values 6.40(6.26~7.75)% of tumor foci in the ccRCC group was significantly higher than that of healthy adult renal (2.05±0.24) %The preliminary results indicate that APT technology has potential clinical application value in the diagnosis of ccRCC.

Yuelang Zhang¹, Xiang Li¹, Chenxia Li¹, Ting Cui¹, Jinhan Wang¹, Shuo Xing², Xianjun Li¹, and Jian Yang^1
1the First Affiliated Hospital of Xi’an Jiaotong University, xi'an, China, ²Xi’an Jiaotong University, xi'an, China

Diffusion and IVIM virtual MR elastography (dMRE) provides quantitative estimates of tissue stiffness without using mechanical vibrations. It rarely applied to identify focal liver lesions (FLL). This retrospective study included 21 subjects (11 malignant lesions and 10 benign lesions). DWI were obtained to calculating dMRE. The kPa values of malignant FLLs (7.93 ± 2.37) was significantly higher than that of benign FLLs (-0.28±5.37) (P < 0.01). ROC showed an AUC of 0.93 for dMRE in differentiating maglinant FLLs and benign FLLs. The sensitivity and specificity were 91% and 90%, respectively. Malignant lesions could be distinguished from benign FLLs by dMRE.