MRI Volumes Research Articles

Biomarkers of disease progression in progressive supranuclear palsy for use in clinical trials

Abstract Progressive supranuclear palsy is a rare neurodegenerative disease with no current disease-modifying treatments approved. Longitudinal research and clinical trials for progressive supranuclear palsy are ongoing and require reliable measures which are sensitive to disease progression. Despite susceptibility to subjective limitations clinical and cognitive assessments are the most used instruments in therapeutic trials in progressive supranuclear palsy. The objective of this review is to identify measures which have been studied longitudinally as measures of progression and which are suitable for use as clinical trial endpoints. We reviewed the measures currently used as trial endpoints, identifying the clinical, cognitive, fluid and imaging measures which have previously been studied longitudinally, and discussing current diagnostic and emerging measures which are yet to be studied longitudinally but which may be sensitive to disease progression. We found that many fluid and imaging measures require further research to validate their use as longitudinal measures of change, including emerging measures which have not yet been studied specifically in progressive supranuclear palsy. We also summarise the sample size estimates required to detect changes in a 2-arm, 52-week therapeutic trial and found that specific MRI volumes require the smallest sample sizes to detect change.

Associations of Central Arterial Stiffness With Brain White Matter Integrity and Gray Matter Volume in MRI Across the Adult Lifespan.

Central arterial stiffening is associated with brain white matter (WM) damage and gray matter (GM) volume loss in older adults, but little is known about this association from an adult lifespan perspective. To investigate the associations of central arterial stiffness with WM microstructural organization, WM lesion load, cortical thickness, and GM volume in healthy adults across the lifespan. This is a cross-sectional study. A total of 173 healthy adults (22-81 years) were included in this study. 3-T, T1-weighted magnetization prepared rapid gradient echo (MPRAGE), single-shot echo-planar imaging diffusion-weighted, and T2-weighted fluid-attenuated inversion recovery (FLAIR) sequences. The participants underwent measurements of central arterial stiffness using carotid-femoral pulse wave velocity (cfPWV), diffusion tensor imaging (DTI) to measure whole-brain WM microstructural organization with free water (FW) and FW-corrected fractional anisotropy (FACOR), FLAIR to measure whole-brain WM hyperintensities (WMH), and MPRAGE to measure whole-brain cortical thickness and GM volume. The associations of age and cfPWV with MRI measures were assessed. Linear regression models to examine the associations of brain WM and GM measures with age, cfPWV, and age × cfPWV interaction after adjusting for sex, education, and intracranial volume (ICV) (voxel-wise and cluster threshold P < 0.05). To understand the direction of the interaction result, the sample was stratified into lower and higher cfPWV groups using a median split of cfPWV. Age × cfPWV interactions were observed in WM FW, WMH volume, cortical thickness, and GM volume (P < 0.01) such that the positive regression slopes between age, FW, and WMH volume were higher, while the negative regression slopes between age, cortical thickness, and GM volume were lower in those who had higher cfPWV relative to those who had lower cfPWV. Central arterial stiffening may accelerate the age-related deteriorations in GM and WM structure across the adult lifespan. Central arterial stiffening is associated with brain white matter (WM) damage and gray matter (GM) volume loss in older adults. We extended this investigation into an adult lifespan perspective by examining the associations of central arterial stiffening with brain structure in adults across age. A total of 172 healthy adults (22-81 years) underwent central arterial stiffening measure using applanation tonometry and brain measurement using MRI. We observed that higher central arterial stiffening may accelerate the age-related deterioration in brain WM and GM structure. These results suggest the importance of maintaining vascular health to slow age-related brain structural changes from an adult lifespan perspective. 4 TECHNICAL EFFICACY: Stage 5.

Primary staging with 2[18F]-FDG-PET/CT and -PET/MRI and radiotherapy response evaluation with MRI in uterine cervical cancer: an interim analysis of a prospective clinical trial

BackgroundIn uterine cervical cancer (UCC), tumour staging is performed according to the 2018 International Federation of Gynecology and Obstetrics (FIGO) system, where imaging is incorporated, or the more generic Tumour Node Metastasis (TNM) classification. With the technical development in diagnostic imaging, continuous prospective evaluation of the different imaging methods contributing to stage determination is warranted. The aims of this interim study were to (1) evaluate the performance of radiological FIGO (rFIGO) and T staging (rT) with 2-fluorine-18-fluoro-deoxy-glucose (2[18F]-FDG)-positron emission tomography with computed tomography (PET/CT) and with magnetic resonance imaging (PET/MRI), compared to clinical FIGO (cFIGO) and T (cT) staging based on clinical examination and conventional imaging, in treatment-naïve UCC, and to (2) identify possible MRI biomarkers for early treatment response after radiotherapy.MethodsTen consecutive patients with newly diagnosed UCC from the prospective PRODIGYN (Prognostic and Diagnostic Added Value of Medical Imaging in Staging and Treatment Planning of Gynecological Cancer) study (ethical approval number 2022-04207-01; NCT05855941) were included. Study participants underwent 2[18F]FDG-PET/CT and -PET/MRI, and an additional MRI one week after radiotherapy. Agreement between rFIGO and cFIGO was analysed using Cohen’s kappa. Differences in rFIGO between 2[18F]FDG-PET/CT and -PET/MRI were evaluated with Wilcoxon signed ranks test, and added value of rFIGO for metastasis assessment was demonstrated with descriptive statistics.ResultsIn 2/10 patients, a higher stage was obtained with rFIGO compared to cFIGO, where presence of metastases led to upstaging. In 3/10, rFIGO was lower than cFIGO, and in 5/10 rFIGO and cFIGO were similar. Degree of agreement between rFIGO and cFIGO was poor, (κ = 0.091, p < 0.005) with 2[18F]FDG-PET/CT and (κ = − 0.010, p > 0.05) with FDG/PET/MRI). There was no significant difference between 2[18F]FDG-PET/CT and -PET/MRI for rFIGO (p = 0.18), or rT stage assessment (p = 0.32). MRI-derived tumour volume and apparent diffusion coefficient (ADC) were most affected on MRI one week after radiotherapy.ConclusionsOur results indicate that there is an added value of rFIGO staging with 2[18F]FDG-PET/CT and -PET/MRI compared to clinical examination and conventional radiology, for metastasis assessment in treatment-naïve UCC. In early treatment response evaluation with MRI, ADC and tumour volume may be predictive parameters of interest in future prognostic analyses.Trial registrationClinical Trials, NCT05855941. Registered 02 May 2023, https://clinicaltrials.gov/study/NCT05855941?term=NCT05855941&rank=1.

Hypothalamic atrophy in primary lateral sclerosis, assessed by convolutional neural network-based automatic segmentation

Primary lateral sclerosis (PLS) is a motor neuron disease (MND) which mainly affects upper motor neurons. Within the MND spectrum, PLS is much more slowly progressive than amyotrophic laterals sclerosis (ALS). `Classical` ALS is characterized by catabolism and abnormal energy metabolism preceding onset of motor symptoms, and previous studies indicated that the disease progression of ALS involves hypothalamic atrophy. Very limited weight loss is observed in patients with PLS, which raises the question of whether there are also less hypothalamic alterations. The purpose of this study was to quantitatively investigate the hypothalamic volume in a group of PLS patients and to compare it with ALS and controls. Recently, we have introduced automatic hypothalamic quantification method based on the use of convolutional neural network (CNN) to reduce human variability and enhance analysis robustness. This CNN of U-Net architecture was applied for automatic segmentation of the hypothalamus and intracranial volume (ICV) to allow adjustments of the hypothalamic volume between subjects with different head sizes respectively. Automatic segmentation and volumetric analysis were performed in high resolution T1 weighted MRI volumes (acquired on a 1.5 T MRI scanner) of 46 PLS patients in comparison to 107 healthy controls and 411 `classical` ALS patients, respectively. Significant hypothalamic volume reduction was observed in PLS (818 ± 73 mm3) when compared to controls (852 ± 77 mm3); significant hypothalamic volume reduction was also confirmed in ALS (823 ± 84 mm3), in support of previous studies. No significant differences were found in normalized hypothalamic volumes between ALS patients and PLS patients at the group level. This unbiased CNN-based hypothalamus volume quantification study demonstrated similarly reduced hypothalamus volume in PLS and ALS patients, despite the clinical phenotypic differences.

SKELETAL MUSCLE MITOCHONDRIAL FUNCTION AND LONGITUDINAL CHANGES IN BRAIN STRUCTURE

Abstract Mitochondrial dysfunction, a hallmark of aging, has been associated with future cognitive impairment or dementia, as well as PET and blood biomarkers of Alzheimer’s disease and neurodegeneration. Whether mitochondrial dysfunction is associated with accelerated loss in brain volumes and microstructural integrity is unknown. We tested the longitudinal association between in vivo muscle mitochondrial oxidative capacity assessed via MR spectroscopy (post-exercise recovery rate of phosphocreatine, kPCr) and changes in brain MRI volumes and DTI microstructure over up to 12 years of follow-up in the Baltimore Longitudinal Study of Aging (2008-2020). In linear mixed effects models, adjusted for demographics, PCr deletion, and physical activity, higher kPCr was associated with less ventricular enlargement, less worsening in MRI-derived brain aging and Alzheimer’s disease scores, and less regional atrophy, especially the primary sensorimotor cortex, temporal white and gray matter, thalamus, occipital areas, cingulate cortex, and cerebellum (n=649). Higher kPCr was also associated with less microstructural integrity loss in white matter tracts connecting identified gray matter areas (n=598). Specific white matter tracts, including splenium of the corpus callosum and superior longitudinal fasciculus showed consistent longitudinal associations in radial diffusivity, but not axial diffusivity, which may indicate demyelination. Higher in vivo mitochondrial function is associated with less worsening in MRI-derived brain aging and Alzheimer’s disease scores, less brain atrophy in specific gray matter regions and less microstructural integrity loss in connecting white matter tracts. Future studies are warranted to investigate the role of CNS mitochondrial function in brain aging and neurodegeneration.

TransGAN: A Transformer‐CNN Mixed Model for Volumetric CT to MRI Modality Translation and Visualization

ABSTRACTMany clinical procedures necessitate the integration of multi‐modality imaging data to facilitate more informed decision‐making. In practice, the cost of scanning and the potential health risks involved often make the scanning of multi‐modality images impractical. It is therefore important to explore the area of modality translation. In recent years, numerous studies have been conducted with the objective of developing methods for translating images between different modalities. Nevertheless, due to the substantial memory requirements and the difficulty in obtaining perfectly paired data, 3D volume modality translation remains a challenging topic. This research proposes a 3D generative adversarial network for the 3D CT‐MRI modality translation task. In order to leverage both low‐level features (pixel‐wise information) and high‐level features (overall image structure), our method introduces both convolutional and transformer structures. Furthermore, our method demonstrates robustness in the presence of imperfectly paired matched CT and MRI volumes from two medical datasets employed in the research. To validate the network performance, qualitative and quantitative comparisons and ablation studies were conducted. The results of the experiments demonstrate that the proposed framework can achieve good results in comparison to four other methods, with improvements of between 10% and 20% in four objective and one subjective evaluation metrics.

Renal Clearable Chiral Manganese Oxide Supraparticles for In Vivo Detection of Metalloproteinase-9 in Early Cancer Diagnosis.

In this study, polypeptide TGGGPLGVARGKGGC-induced chiral manganese dioxide supraparticles (MnO2 SPs) are prepared for sensitive quantification of matrix metalloproteinase-9 (MMP-9) in vitro and in vivo. The results show that L-type manganese dioxide supraparticles (L-MnO2 SPs) exhibited twice the affinity for the cancer cell membrane receptor CD47 (cluster of differentiation, integrin-associated protein) than D-type manganese dioxide supraparticles (D-MnO2 SPs) to accumulate at the tumor site after surface modification of the internalizing arginine-glycine-aspartic acid (iRGD) ligand, specifically reacting with the MMP-9, disassembling into ultrasmall nanoparticles (NPs), and efficiently underwent renal clearance. Furthermore, L-MnO2 facilitates the quantification of MMP-9 in mouse tumor xenografts, as demonstrated by circular dichroism (CD) and magnetic resonance imaging (MRI) within 2 h. A strong linear relationship is observed between MMP-9 concentration and both CD and MRI intensity, ranging from 0.01 to 10ngmL-1. The corresponding limits of detection (LOD) are 0.0054ng mL-1 for CD and 0.0062ng mL-1 for MRI, respectively. hese SPs provide a new approach for exploring chiral advanced biosensors for early diagnosis of cancer.

Weakly supervised brain tumour segmentation with label propagation and level set loss

AbstractEarly diagnosis of brain tumors significantly enhances treatment success. However, accurate detection and segmentation of tumors, essential for diagnosis, rely heavily on costly manual annotation by experts. To mitigate these costs, weakly supervised methods have gained traction. This paper introduces a novel weakly supervised brain tumor segmentation approach utilizing point and scribble supervision. Experts annotate only the slice with the largest tumor area by marking a single point near the tumor center or drawing a scribble within the tumor region. The method operates in two phases. First, labels are propagated to unlabelled pixels, generating a pseudo‐ground‐truth with three labels: tumor, non‐tumor, and marginal pixels (unlabelled pixels surrounding the initial segmentation). Second, a segmentation model is trained using the pseudo‐ground‐truth and a loss function combining level‐set and binary cross‐entropy losses. Marginal pixels contribute to level‐set loss computation, refining the segmentation process. The approach is validated on 3D magnetic resonance imaging (MRI) volumes from BraTS2020, BraTS2021, and BraTS2023 benchmark datasets. Experimental results show Dice scores comparable to fully supervised methods for whole tumor segmentation, demonstrating the effectiveness of the proposed weakly supervised strategy. This method reduces annotation effort while maintaining competitive segmentation performance, making it valuable for clinical applications.

Impact of Discordance Between Magnetic Resonance Imaging and Ultrasound Volume Measurements on Prostate Fusion Biopsy Outcomes.

To determine whether the difference between MRI-based and ultrasound (US)-based volume measurements are associated with MRI/US-targeted fusion-guided biopsy outcomes. This retrospective, single-center study involved 4177 consecutive patients biopsied between 2010 and 2023 using both MRI/US-targeted fusion and systematic biopsy. Biopsies were indicated because of elevated PSA levels or abnormal multiparametric MRI results. US volume measurements were calculated using the triplane ellipsoid formula, and MRI volumes were obtained by semiautomatic planimetric segmentation. Performance of fusion biopsy compared with systematic biopsy was analyzed with respect to the discordance between MRI and US volume measurements. In 2736 patients (66%), biopsy detected prostate cancer. In cases where both techniques yielded prostate cancers (1695/2736 [62%]), a statistically higher proportion of patients had higher Gleason scores on MRI/US-targeted fusion biopsy compared with systematic biopsy (343 patients [20.2%] vs 137 patients [8.1%], P < .001). MRI volume measurements were significantly smaller compared with US volume measurements (median [IQR] 54 mL [39-77], 56 mL [40-80], respectively, P < .001). Beyond 5 mL volume discordance, MRI/US-targeted fusion biopsy gradually showed less added diagnostic benefit compared with systematic biopsy. In the ≤ 5 mL cohort, MRI/US-targeted fusion biopsy detected more aggressive tumors in 4 times as many patients than systematic biopsy (136 vs 32 patients, P < .001). Although MRI/US-targeted fusion biopsy detected more prostate cancers than systematic biopsy, the performance of MRI/US-targeted fusion biopsy declined with more discordance between volumes measured in MRI vs US. Awareness of volume discordance in MRI and US-based volume measurements should alert the operator about the possibility of reduced performance of MRI/US-targeted fusion biopsy.

Safety and therapeutic potential of allogeneic adipose-derived stem cell spray transplantation in ischemic cardiomyopathy: a phase I clinical trial

BackgroundIschemic cardiomyopathy, characterized by coronary artery atherosclerosis, impairs the myocardial tissue. Coronary artery bypass grafting (CABG) is commonly used to revascularize affected areas and improve patient survival rates; however, it can fail to enhance cardiac function. Impaired capillary blood flow may obstruct functional recovery, prompting interest in treatments, such as angiogenic factor administration. Adipose-derived stem cells (ADSCs), which are known for immune evasion, have shown the potential to construct capillary networks and improve myocardial function. This clinical trial aimed to evaluate the safety and efficacy of ADSC spray therapy combined with CABG.MethodsThis single-center, randomized, double-blind study involved patients with ischemic cardiomyopathy who were scheduled for CABG and who had a left ventricular ejection fraction ≤ 40%. The participants were randomized to receive CABG as well as ADSC spray therapy or placebo. The primary endpoints were safety, changes in late gadolinium-enhanced (LGE) magnetic resonance imaging (MRI) volumes, and feasibility. The secondary endpoints included left ventricular function, exercise tolerance, and heart failure symptoms.ResultsSeven patients were enrolled; of them, six were randomized to receive ADSC therapy (n = 3) or placebo (n = 3). The procedure was successfully completed with minimal adverse events. One patient in the ADSC group developed pleural effusion that was resolved with drainage. The LGE-MRI volumes decreased in the ADSC group but remained unchanged in the placebo group. Improvements in left ventricular function and exercise tolerance were noted in the ADSC group, with heart failure symptoms improving to New York Heart Association class I. In contrast, the placebo group showed no significant changes, with one patient experiencing worsening symptoms.ConclusionsADSC spray therapy combined with CABG demonstrated safety and efficacy at enhancing cardiac function. ADSC likely contributes to capillary network reconstruction, thereby augmenting the benefits of CABG. Future phase II and III trials are warranted to confirm its therapeutic efficacy and long-term outcomes. This novel approach represents a significant advancement in the treatment of ischemic cardiomyopathy and offers a viable strategy for improving myocardial function and patient prognosis.Trial registration This study was registered with the Japan Registry of Clinical Trials (jRCT2053190103) and ClinicalTrials.gov (NCT04695522)Graphical

Hypertonic water reabsorption with a parallel-current system via the glandular and saccular renal tubules of Ruditapes philippinarum.

We investigated the renal function of the brackish water clam, Ruditapes philippinarum, employing magnetic resonance imaging (MRI). The R. philippinarum kidney consists of two renal tubules, a glandular (GT) and a saccular (ST) tubule. After exposure to seawater containing manganese ion (Mn2+) at 20°C, the intensity of the T1-weighted MRI and longitudinal relaxation rates (1/T1=R1) of the kidney were increased. In the ST, haemolymph containing Mn2+ entered directly from the auricle, and the Mn2+ concentration ([Mn2+]) increased in the initial part of the ST. Thereafter, [Mn2+] was almost constant until the posterior end of the kidney. The GT received haemolymph from the pedal sinus via the visceral sinus. The GT runs parallel inside the ST, and [Mn2+] increased progressively until it merged with the ST. In a range of seawater with [Mn2+] from 1 to 30 µmoll-1, the [Mn2+] increased 12-fold in the posterior part of the ST, compared with the ambient [Mn2+]. Based on these results, the epithelium of the initial part of the ST reabsorbs water from luminal fluid, building up a higher osmotic pressure. Using this osmotic gradient, hypertonic water is reabsorbed via the epithelium of the GT to the ST, and then transferred to the haemolymph via the epithelium of the ST. Excess water is excreted as urine. This model was supported by the increases in [Mn2+] in the ST when the clams were exposed to seawater containing Mn2+ at salinity from 26.0 to 36.0‰, showing that the parallel-current system works in hypotonic seawater.

Abstract 4136863: Diffuse Functional and Structural Abnormalities in Fibrosis: Potential Structural Basis for Sustaining Atrial Fibrillation

Background: Structural remodeling is associated with atrial fibrillation (AF), but detailed structural and functional characteristics is not well defined. Goal: Using a novel transgenic goat model with cardiac-specific overexpression of TGF-β1 leading to increased cardiac fibrosis, we evaluated detailed structural and functional differences between fibrotic and healthy regions of the atria. Methods: Ex-vivo MRI and histology were used to evaluate fibrosis, fiber disarray, and structural anisotropy. Ex-vivo MRI intensity values were scaled to standard deviations around the mean. The functional analysis examined conduction speeds and direction heterogeneity. Conduction anisotropy was measured along the fiber direction obtained with diffusion tensor imaging. Results: The transgenic goats (n=12) had, on average, 21% of the left atria labeled as fibrotic determined from ex-vivo MRI. The histology samples taken from the labeled fibrotic regions had an increase in fibrosis percentage compared to labeled healthy regions (7.78±3.76% vs 2.80±1.86%, p&lt;0.01). The structural anisotropy was lower in fibrotic regions (0.196±0.002 vs 0.244±0.002, p&lt;0.01). Fiber disarray was greater in the fibrotic regions (20.3±0.2° vs 19.2±0.1°, p&lt;0.01). The fibrotic regions had slower conduction speeds (0.78±0.02 m/s vs 1.12±0.02 m/s, p&lt;0.01) and more aligned conduction directions (30.5±0.2° vs 31.6±0.1°, p&lt;0.01), potentially developing unidirectional conduction block. Conduction anisotropy, measured on the fiber directions, was found to be lower in the fibrotic regions (1.86±0.05 vs 2.10±0.02, p=0.04). As scaled MRI intensity increased, the conduction speed, heterogeneity, and anisotropy all decreased. Conclusions: Functional and structural differences exist between fibrotic and healthy regions of the atria. Though statistically significant, the changes are not discrete. The correlation showed gradual functional abnormalities with MRI intensities. Fibrotic regions tended to have increased fiber disarray, slower conduction, and more unidirectional propagation with lower conduction and structural anisotropy. Diffuse functional and structural abnormalities may allow fibrotic regions to serve as a substrate to sustain AF.

Clinical and Imaging features associated with malignant focal non-mass enhancement on breast MRI

Introduction: Focal non-mass enhancement (NME) is a common breast MRI finding with limited data to guide management. This study aimed to assess clinical and imaging features of malignant BI-RADS 4 focal NME. MethodsThis IRB-approved, retrospective study included breast MRI exams between August 1, 2013 and September 1, 2022 yielding BI-RADS 4 focal NME lesions that underwent core biopsy or excision with available pathology result or demonstrated decrease or resolution during follow-up MRI or at least two years of MRI stability. ResultsA total of 296 BI-RADS 4 focal NME lesions in 246 patients were included in the study. The overall malignancy rate of BI-RADS 4 focal NME was 36/296 (12.2%). Focal NME in a patient presenting for evaluation of extent of disease or other diagnostic concern was 5.5 and 3.4 times more likely, respectively, to be malignant compared to focal NME seen on a high-risk screening exam. There was also a significant association between malignancy and focal NME that was brighter than background parenchymal enhancement (BPE) on maximum intensity projection (MIP) images. There was no significant association between malignancy and lesion size, internal enhancement pattern, amount of BPE, amount of fibroglandular tissue, or signal intensity on T2-weighted images. ConclusionOur study yielded a malignancy rate of 12.2% for BI-RADS 4 focal NME lesions. Indication for MRI and signal intensity compared to BPE on MIP images were features associated with malignancy that may provide guidance on the management for focal NME. Micro abstractFocal non-mass enhancement (NME) is a common breast MRI finding with limited data to guide management. In this rertospective study of 296 BI-RADS 4 focal NME lesions in 246 patients, 36/296 (12.2%) were malignant. Lesions were more likely to be malignant if they were brighter than background parenchymal enhancement or if the exam was a diagnostic, rather than screening, exam.

Progressive postoperative atrophy of ipsilateral thalamus, putamen, and globus pallidus in patients with temporal lobe epilepsy: A volumetric analysis.

Cortical atrophy close to medial temporal structures has been described consistently in patients with temporal lobe epilepsy (TLE). Successful TLE surgery may have a neuroprotective effect preventing further atrophy of temporal and extratemporal cortex. However, the effects of epilepsy surgery on subcortical structures demand additional enlightenment. This work aimed to determine how epilepsy surgery affects volumes of subcortical structures in medically refractory temporal lobe epilepsy patients. We compared MRI volumes of subcortical structures in 62 patients with TLE (36 left, 26 right) before and after anterior temporal lobectomy with 38 TLE patients (20 left, 18 right) who were considered to be good surgical candidates and had at least two brain MRIs. There were no volume differences in subcortical structures on preoperative and initial MRIs of non-operated TLE patients. At baseline, the ipsilateral thalamus and putamen in TLE patients were marginally smaller than contralateral structures. Operated patients showed a significant postoperative volume reduction in ipsilateral thalamus, putamen, and globus pallidus. In contrast, there were no significant volumetric reductions in non-operated patients longitudinally. There were no volumetric changes associated with different surgical outcomes or different postoperative cognitive outcomes. Our study demonstrated postoperative volume loss of thalamus, putamen and globus pallidus ipsilaterally to the side of resection. Our findings suggest surgery-related changes, likely Wallerian degeneration within subcortical networks not related to seizure or cognitive outcome. We studied 100 patients with epilepsy, comparing those who had surgery to those who did not. After surgery, the thalamus, putamen and globus pallidus on the same side as the surgery shrank significantly, but not in non-surgery patients. This suggests surgery-related changes in deeper brain structures, unrelated to seizure freedom or cognitive outcomes. This research sheds additional light on the response of the subcortical structure to epilepsy surgery, highlighting potential areas for further study.

P13.01.A 11C-METHIONIN PET FOR RADIOTHERAPY TREATMENT PLANNING IN PATIENTS WITH RAPID EARLY PROGRESSION AFTER GLIOBLASTOMA SURGERY: PROSPECTIVE PHASE II TRIAL

Abstract BACKGROUND Radiotherapy (RT) is a standard treatment for nearly all glioblastoma patients following initial surgery. Few retrospective studies indicate negative prognostic instances of progression during the planning magnetic resonance (MR) (up to 1 week before initiating RT), termed Rapid Early Progression (REP). The optimal RT management for REP patients remains uncertain. The objective of this prospective phase II trial (NCT05608395) is to assess impact of 11C-Methionine PET used for RT planning in REP glioblastoma patients. It is one of the first prospective clinical interventional trials focused on this specific cohort of patients. MATERIAL AND METHODS We enrolled glioblastoma, IDHwt, or Astrocytoma, IDHmt, WHO grade IV patients, who developed REP characterized by 1) increase in postoperative residuum by ≥ 25%, 2) appearance of new contras enhancing lesion, 3) unequivocal progression of the unresected satelite. Patients received treatment based on the Stupp or Perry protocol. Treatment response was evaluated using RANO criteria. RT target volumes were delineated as follows: Gross tumor volume included tumor cavity, enhancing lesion and 11C-MET PET (1.3 tumor-to-background ratio). The clinical target volume was GTV plus a modified 2cm margin reflecting surrounding organs at risk. Volumetric analyses of different radiotherapy target volume were performed using EclipseTM software including patterns of failure. RESULTS During 12/2020 - 12/2023, total of 31 patients were enrolled (16 treated via abbreviated RT course); median age 60 years, ECOG 0-1 in 28 patients, median follow up 20 months. No effect of 11C-MET PET - based radiotherapy treatment planning of GBM patients with REP was observed on PFS (median 3.4 months comparing to 4.9 in historical control cohort) and OS (12.3 months comparing to 15.7 months). Median MET volume was 7.3cm3 (43% of MRI volume), MET avidity was presented in 7 patients et least 1cm beyond MRI volume. Central recurrence was presented in 87% patients. CONCLUSION The optimal treatment of patients with REP is unknown and needs to be studied in more details including dose escalation studies with reduced target margins potentialy directed also by aminoacid PET examination. Adjustment of target radiotherapy volumes using 11C-MET PET did not lead to improved PFS or OS. Supported by NU20-03-00148.

Fusion Imaging Objectively Demonstrates Improved Pancreas Visualization through Manipulation Techniques: A Prospective Interventional Study.

Objective Abdominal ultrasonography (AUS) is used to screen for abdominal diseases owing to its low cost, safety, and accessibility. However, the detection rate of pancreatic disease using AUS is unsatisfactory. We evaluated the visualization area of the pancreas and the efficacy of manipulation techniques for AUS with fusion imaging. Methods Magnetic resonance imaging (MRI) volume data were obtained from 20 healthy volunteers in supine and right lateral positions. The MRI volume data were transferred to an ultrasound machine equipped with a fusion imaging software program. We evaluated the visualization area of the pancreas before and after postural changes using AUS with fusion imaging and assessed the liquid-filled stomach method using 500 ml of de-aerated water in 10 randomly selected volunteers. Patients This study included 20 healthy volunteers (19 men and 1 woman) with a mean age of 33.0 (21-37.5) years old. Results Fusion imaging revealed that the visualization area of the entire pancreas using AUS was 55%, which significantly improved to 75% with a postural change and 90% when using the liquid-filled stomach method (p=0.043). Gastrointestinal gas is the main obstacle for visualization of the pancreas. Conclusion Fusion imaging objectively demonstrated that manipulation techniques can improve pancreatic visualization.

Isotropic Brain MRI Reconstruction from Orthogonal Scans Using 3D Convolutional Neural Network.

As an alternative to true isotropic 3D imaging, image super-resolution (SR) has been applied to reconstruct an isotropic 3D volume from multiple anisotropic scans. However, traditional SR methods struggle with inadequate performance, prolonged processing times, and the necessity for manual feature extraction. Motivated by the exceptional representational ability and automatic feature extraction of convolutional neural networks (CNNs), in this work, we present an end-to-end isotropic MRI reconstruction strategy based on deep learning. The proposed method is based on 3D convolutional neural networks (3D CNNs), which can effectively capture the 3D structural features of MRI volumes and accurately predict potential structure. In addition, the proposed method takes multiple orthogonal scans as input and thus enables the model to use more complementary information from different dimensions for precise inference. Experimental results show that the proposed algorithm achieves promising performance in terms of both quantitative and qualitative assessments. In addition, it can process a 3D volume with a size of 256 × 256 × 256 in less than 1 min with the support of an NVIDIA GeForce GTX 1080Ti GPU, which suggests that it is not only a quantitatively superior method but also a practical one.

The Influence of Birth Weight, Socio-Economic Status, and Adult Health on Brain Volumes during Ageing

Introduction: Greater late-life brain volumes are associated with resilience against dementia. We examined relationships between birth weight, lifelong socio-economic status, and health with late-life brain volumes. We hypothesised that early life factors directly affect late-life brain volumes. Methods: Adults aged 59–67 y underwent MRI and brain volumes were measured. Birth weight and lifelong health, and socio-economic status were quantified and the principal components of each extracted. Relationships were examined using regression and structural equation analysis. Results: Birth weight (β = 0.095, p = 0.017) and childhood socio-economic status (β = 0.091, p = 0.033, n = 280) were directly associated with brain volume. Childhood socio-economic status was further associated with grey matter volume (β = 0.04, p = 0.047). Adult health was linked to increased brain volume (β = 0.15, p = 0.003). Conclusion: Birth weight and childhood socio-economic status are associated with whole and regional brain volume through direct mechanisms. Optimal fetal development, reduced childhood poverty, and good adult health could reduce brain atrophy and delay dementia onset in late-life.

Detecting Amyloid Positivity Using Morphometric Magnetic ResonanceImaging.

Early detection of amyloid-β (Aβ) positivity is essential for an accurate diagnosis and treatment of Alzheimer's disease (AD), but it is currently costly and/or invasive. We aimed to classify Aβ positivity (Aβ+) using morphometric features from magnetic resonance imaging (MRI), a more accessible and non-invasive technique, in two clinical population scenarios: one containing AD, mild cognitive impairment (MCI) and cognitively normal (CN) subjects, and another only cognitively impaired subjects (AD and MCI). Demographic, cognitive (Mini-Mental State Examination [MMSE] scores), regional morphometry MRI (volumes, areas, and thicknesses), and derived morphometric graph theory (GT) features from all subjects (302 Aβ+, age: 73.3±7.2, 150 male; 246 Aβ-, age: 71.1±7.1, 131 male) were combined in different feature sets. We implemented a machine learning workflow to find the best Aβ+ classification model. In an AD+MCI+CN population scenario, the best-performing model selected 120 features (107 GT features, 12 regional morphometric features and the MMSE total score) and achieved a negative predictive value (NPVadj) of 68.4%, and a balanced accuracy (BAC) of 66.9%. In a AD+MCI scenario, the best model obtained NPVadj of 71.6%, and BAC of 70.7%, using 180 regional morphometric features (98 volumes, 52 areas and 29 thicknesses from temporal, parietal, and frontal brain regions). Although with currently limited clinical applicability, regional MRI morphometric features have clinical usefulness potential for detecting Aβ status, which may be augmented by a combination with cognitive data when cognitively normal subjects make up a substantial part of the population presenting for diagnosis.

Correlation between D-Dimer and Size of Non-Lacunar MCA Infarction and its Relation to Functional Outcome

Abstract Background Stroke is the second highest cause of death globally and a leading cause of disability, with an increasing incidence in developing countries. D-dimer (D-D) is the ultimate product of plasmin-mediated degradation of fibrin-rich thrombi. D-D is a simple readily accessible biomarker employed within the diagnostic algorithms for the exclusion of venous thromboembolism. The correlation between D-D and infarct size in MRI brain in acute stroke patients and predict their functional outcome by using modified Rankin scale (mRS) has not been fully investigated before. Objectives We aimed to investigate correlation between plasma D-Dimer level and the ischemic lesion size of non-lacunar MCA infarction in MRI brain and predict functional outcome of these patients. Patients and Methods This cross sectional study Included 30 acute ischemic stroke (MCA) patients fulfilled the inclusion and exclusion criteria admitted to Stroke Unites of Ain Shams University hospitals in which particle-enhanced, immunoturbidimetric assay to detect plasma D-Dimer concentration measured upon admission. additionally, demographic, clinical, laboratory, and neuroimaging information was Abstracted. Also, using mdified Rankin scale (mRS) to follow up patients as a tool to assess functional outcome. Results In this study there was a statistically significant positive correlation between of D-dimer levels on admission and the initial infarction volume in MRI (DWI) (Test-value)=21.28 and p-value.000). The Increase of D-dimer level was associated with increase of the initial infarction volume in MRI and vice versa. There was direct statistically significant positive correlation between the D-dimer and the mRS scores of the patients (r=.155 and p- value = .005)and the best cut- off limit of D-dimer levels done to patients early after admission (in the 1st 24 hours) in predicting poor outcome was 650 ng/ml which achieves 85.71 % sensitivity and 87.5% specificity. Conclusion The plasma D-D biomarker can be a simple readily available test reliable predictor of infarct lesion size in DW-MRI and functional outcome for patients with ischemic stroke in union with the common practice instrumental tests.