BACKGROUND:Several techniques have been designed to increase the size of the future liver rem-nant (FLR) prior to liver resection. This experimental study in pigs builds on our previous rat study, in which we demonstrated that portal vein ligation (PVL) combined with radiofrequency ablation (RFA)-termed Associated Radiofrequency Ablation and Portal Vein Ligation for Staged Hepatec-tomy (ARAPS)-induces accelerated future liver remnant (FLR) growth comparable to the ALPPS procedure. METHODS:Eighteen female pigs were randomly assigned to PVL, ARAPS, or as controls. On post operative day (POD) 0, blood samples were collected, and 18F-FDGal PET and ceCT scans were conducted. Intervention pigs underwent either PVL or ARAPS. On POD 7, intervention pigs were re-evaluated with blood samples and 18F-FDGal PET/ceCT scans. Liver biopsies were obtained from the devascularized liver on POD 0 and POD 7, and from the FLR on POD 7 for histological analysis and growth rate kinetics. Control pigs were assessed only on POD 0. RESULT:The median FLR volume increase was comparable between the two groups at POD 7 (p=0.52). Further a shift in the distribution of liver function between the FLR and the deportalized liver was observed at POD 7 without significant difference in 18F-FDGal accumulation (percentage of injected dose in the liver) between groups (p = 0.15). The biochemical liver response did not differ between groups at any time. Additionally, no differences in hepatocyte morphology were found at POD 0. At POD 7, increased hepatocyte hypertrophy (p<0.004) and proliferation (p<0.001) were found in the ARAPS group compared to PVL. The regenerative capacity was most prominent in the FLR compared to the deportalized liver. CONCLUSION:ARAPS may enhance the proliferative response of the FLR compared to PVL alone, while still maintaining liver function comparable to PVL.

Purpose To assess the feasibility of hyperpolarized [1-13C]pyruvate MRI (HP-MRI) as an adjunct to standard CT/MRI-based Liver Imaging Reporting and Data System (LI-RADS) categorization for noninvasive metabolic characterization of hepatocellular carcinoma (HCC). Materials and Methods This prospective, exploratory, single-center study included participants with liver lesions and control participants who underwent HP-MRI between June 2023 and June 2025. Lesions identified on CT and/or MRI scans were categorized according to LI-RADS. HP-MRI metabolic readout included ratios from dynamic 13C imaging, such as the lactate-to-pyruvate (L/P) ratio, alanine-to-pyruvate (A/P) ratio, alanine-to-lactate (A/L) ratio, and corresponding tumor-to-background ratios (TBRs). Established HCCs were compared with indeterminate lesions that subsequently progressed to HCC using unpaired t tests and Hedges g. Results Fourteen participants were included (median age, 64 years; IQR, 53-70 years]; 14 [100%] male): 10 participants with lesions on CT/MRI scans and four control participants. A/P and A/L ratios were lower in indeterminate lesions that progressed (n = 4) than established HCCs (n = 5), both in absolute measures and indexed to TBRs (P < .05), whereas there was no evidence of differences in the L/P ratio. In contrast, L/P TBR was higher in indeterminate lesions that progressed than in established HCCs (P = .03). Alanine-indexed TBRs showed large effect sizes, with Hedges g ranging from 2.01 (95% CI: 0.33, 3.70) to 3.02 (95% CI: 0.97, 5.08). One LI-RADS category 3 (LR-3) lesion under surveillance showed no early progression, and progression could not be confirmed for an LR-4 lesion. Conclusion Adjunctive HP-MRI provided complementary lesion-level metabolic information beyond standard CT and/or MRI, and a reduced A/L ratio emerged as a candidate marker of malignant progression. Keywords: Liver, Oncology, Cirrhosis, Hepatocellular Carcinoma Supplemental material is available for this article. Clinical Trials Information System hosted by the European Medicines Agency (EU-CTIS 2024-512490-27-00) © RSNA, 2026.

Assessment of liver function is essential before partial hepatectomy to predict the risk of post hepatectomy liver failure, a severe and life-threatening complication. Traditional methods have focused on expected future liver remnant (FLR) volume estimation. However, liver volume does not always correlate with function. We suggest that metabolism might be a better surrogate for function than volume. Therefore, we aimed to investigate the metabolic changes in a porcine model of partial portal vein ligation (PVL) using hyperpolarized magnetic resonance imaging (HP-MRI). Specifically, we sought to quantify and compare the pyruvate metabolism in the FLR and the deportalized liver (DL). Six pigs underwent PVL. HP-MRI with [1-13C] pyruvate was performed at baseline, post-surgery, and 1 week after surgery. Metabolic conversion was quantified with kinetic modelling of the rate constants of pyruvate to lactate (kPL) and pyruvate to alanine (kPA). Mean kPL was increased in FLR compared to DL at post-surgery and 1 week after surgery (P = 0.002), while kPA was unaltered (P = 0.761). These findings indicate a metabolic shift towards glycolysis in the FLR. This non-invasive metabolic imaging technique could serve as a powerful tool for evaluation of regional liver function prior to partial hepatectomy and consequently improve patient outcomes.

PURPOSE:To investigate the in vitro precision and linearity of 3D whole-liver covering dual flip angle (DFA) T1 mapping and compare different circular ROI sampling strategies in vivo. METHODS:All scans were performed at 3 T using a commercially available three-dimensional steady-state spoiled gradient echo with DFA. The in vitro study was performed on the EUROSPIN Test Object 5 with inversion recovery turbo spin echo (IRTSE) performed for reference T1 values. The in vivo study was performed in 30 patients before and after gadoxetic acid. In vitro DFA T1 map was compared to IRTSE T1 map voxel-by-voxel. In vivo DFA T1 maps were manually segmented for mean-segment T1. Two readers estimated segmental T1 using 4 ROI sampling strategies. Inter-reader agreement was assessed, and ROI sampling strategies were compared to manual segmentation. Linear regression, Bland-Altman plots and comparison of correlations were performed. RESULTS:In vitro DFA T1 measurements showed strong linearity with R2 = 0.9912 (P < 0.0001) compared to IRTSE with 16.33 % overestimation. In vivo ROI-based estimated segmental T1 demonstrated improved inter-reader agreement with R2 increasing from 0.9135 to 0.9601 (P < 0.003) and narrower limits-of-agreement as the ROI area increased. Agreement with manual segmentation-based mean-segment T1 improved with increasing ROI area (R2 0.9718 to 0.9778 and 0.9359 to 0.9722, for reader 1 and 2 respectively) as well as narrower limits-of-agreement. CONCLUSION:DFA T1 measurements had a strong linearity with a minor overestimation. The use of larger ROI areas leads to better agreement with manual segmentation and improved inter-reader agreement.

Comparison of the time to relapse detection using CEA and standard-of-care CT imaging for fourteen relapse patients.

List of Supplementary Tables

Detection of ctDNA in pre-operative plasma samples according to stage.

Comparison of serial ctDNA analysis performed using SSV and SPM ddPCR assays.

Purpose: To prospectively compare artefacts and image quality in testicular stage I cancer patients using different combinations of breathing schemes and Multi-band (MB) in whole-body DWIBS at 1.5 T.Diffusion-Weighted whole-body Imaging with Background body signal Suppression (DWIBS) using inversion recovery (IR) fat saturation is a cornerstone in oncologic whole-body MRI, but implementation is restrained by long acquisition times. The new Multi-Band (MB) technique reduces scan time which can be reinvested in respiratory compensation. Methods: Thirty testicular cancer stage I patients were included. Three variations of whole-body DWIBS were tested: Standard free Breathing (FB)-DWIBS, FB-MB-DWIBS and Respiratory triggered (RT)-MB-DWIBS. Artefacts and image quality of b = 800 s/mm2 images were evaluated using a Likert scale. No pathology was revealed. SNR was calculated in a healthy volunteer. Results: RT-MB-DWIBS was rated significantly better than FB-DWIBS in the thorax (p < 0.001) and abdomen (p < 0.001), but not in the pelvis (p = 0.569). FB-MB-DWIBS was ranked significantly lower than both FB-DWIBS (p < 0.001) and RT-MB-DWIBS (p < 0.001) at all locations. However, FB-MB-DWIBS was scanned in half the time without being less than “satisfactory”. Few artefacts were encountered. SNR was similar for low-intensity tissues, but the SNR in high-intensity and respiratory-prone tissue (spleen) was slightly lower for FB-DWIBS than the other sequences. Conclusion: Images produced by the sequences were similar. MB enables the use of respiratory trigger or can be used to produce very fast free-breathing DWI with acceptable image quality.

Purpose: To compare image quality and ADC values of simultaneous multislice diffusion-weighted imaging (mb-DWI) with that of conventional DWI (c-DWI) using short tau inversion recovery fat saturation (STIR) in women with bone-metastasizing breast cancer. Method: c-DWI and mb-DWI were acquired at 1.5 T in 23 breast cancer patients from skull base to mid thighs. mb-DWI was compared to c-DWI in terms of subjective image quality, artefacts and bone metastasis lesion conspicuity assessed on a 5-point Likert scale. ADC values of different organs as well as bone metastasis ADC values were compared between c-DWI and mb-DWI. Results: mb-DWI reduced scan time by 48 % compared with c-DWI (1 min 58 s vs. 3 min 45 s per station). mb-DWI provided similar subjective image quality (3.8 vs. 3.7, p = 0.70), number of artefacts (50 vs. 56), severity of these (4.6 vs. 4.7, p = 0.11), and lesion conspicuity (4.2 vs. 4.4, p = 0.31) compared to c-DWI. mb-DWI showed lower mean ADC values in liver (0.5 x 10(-3) mm(2)/s vs. 0.7 x 10(-3) mm(2)/s, p = 0.002) and erector spine muscle (1.3 x 10(-3) mm(2)/s vs. 1.5 x 10(-3) mm(2)/s, p < 0.001). Bone metastasis ADC values from mb-DWI were 6.4 % lower than c-DWI (95 % confidence interval: 5.4%-7.4%, p < 0.001). Conclusions: mb-DWI provides similar subjective image quality to c-DWI with the same level of artefacts. Although bone metastasis ADC values were lower, mb-DWI can substantially reduce scan times of whole-body DWI in women with bone-metastasizing breast cancer.

Purpose: To assess diagnostic performance of fat fractions (FF) from high-resolution 3D radial Dixon MRI for differentiating metastatic and non-metastatic axillary lymph nodes in breast cancer patients. Method: High-resolution 3D radial Dixon MRI was prospectively performed on 1.5 T in 70 biopsy-verified breast cancer patients. 35 patients were available for analysis with histopathologic and imaging data. FF images were calculated as fat / in-phase. Two radiologists measured lymph node FF and assessed morphological features in one ipsilateral and one contralateral lymph node in consensus. Diagnostic performance of lymph node FF and morphological criteria were compared using histopathology as reference. Results: 22 patients had metastatic axillary lymph nodes. Mean lymph node FF were 0.20 +/- 0.073, 0.31 +/- 0.079, and 0.34 +/- 0.15 (metastatic, non-metastatic ipsi- and non-metastatic contralateral lymph nodes, respectively). Metastatic lymph node FF were significantly lower than non-metastatic ipsi- (p < 0.001) and contralateral lymph nodes (p < 0.001). Area under the receiver operating characteristics curve for lymph node FF was 0.80 compared to 0.76 for morphological criteria (p = 0.29). Lymph node FF yielded sensitivity 0.91, specificity 0.69, positive predictive value (PPV) 0.83, and negative predictive value (NPV) 0.82, while morphological criteria yielded sensitivity 0.91, specificity 0.62, PPV 0.80, and NPV 0.80 (p = 0.71). Combining lymph node FF and morphological criteria increased diagnostic performance with sensitivity 1.00, specificity 0.67, PPV 0.86, NPV 1.00, and AUC 0.83. Conclusions: Lymph node FF from high-resolution 3D Dixon images are a promising quantitative indicator of metastases in axillary lymph nodes.

Background Fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) can detect extrahepatic disease before local treatment of colorectal liver metastases. Purpose To investigate if whole-body magnetic resonance imaging (MRI) added to gadoxetic acid liver MRI could replace FDG-PET/CT for detection of extrahepatic disease in patients with colorectal liver metastases eligible for hepatic local treatment. Material and Methods This health-research-ethics-committee-approved prospective consecutive diagnostic accuracy study with written informed consent analyzed 79 cases included between 29 June 2015 and 7 February 2017. Whole-body MRI covering the thorax, abdomen, and pelvis and FDG-PET/CT including contrast-enhanced CT was performed 0–3 days before local treatment of liver metastases. Whole-body MR images were read independently by two readers. FDG-PET/CT images were read independently by two pairs of readers. Histopathology and follow-up imaging were used as reference standard. Sensitivities and specificities were calculated and compared including noninferiority analysis. Results Seventy-five malignant lesions and 419 benign lesions were confirmed. Sensitivities of both PET/CT reader pairs 1 and 2 (56.7 and 67.9%) and MRI reader 2 (63.0%) were significantly higher than that of MRI reader 1 (42.7) (P<0.04). Specificities of both PET/CT reader pairs 1 and 2 (92.5 and 92.4%) and MRI reader 1 (91.1%) were significantly higher than that of MRI reader 2 (86.3%) ( P < 0.02). Sensitivity of MRI reader 2 was non-inferior compared to PET/CT reader pair 1. Specificities of both MRI readers were non-inferior to both PET/CT reader pairs. Conclusion For detection of extrahepatic disease in patients with colorectal liver metastases, whole-body MRI was non-inferior to FDG-PET/CT for some reader combinations. However, reader-independent non-inferiority could not be demonstrated.

To compare the diagnostic performance of contrast-enhanced computed tomography (CE-CT), magnetic resonance imaging (MRI) and combined fluorodeoxyglucose/positron emission tomography/computed tomography (FDG-PET/CT) for detection of colorectal liver metastases (CRLM) in patients eligible for local treatment.

Purpose: To compare three magnetic resonance imaging (MRI) protocols containing diffusion-weighted imaging with background suppression (DWIBS) and one traditional protocol for detecting extrahepatic colorectal cancer metastases. Materials and Methods: Thirty patients with extrahepatic colorectal cancer metastases were scanned in three stations from the skull base to the upper thighs using a 1.5T MRI system with six different MRI sequences; transverse and coronal T-2-weighted (T2W) turbo spin-echo (TSE), coronal short tau inversion recovery (STIR), 3D T1W TSE, DWIBS, and a contrast-enhanced T1W 3D gradient echo (GRE) sequence. The six sequences were used to build four hypothetical MRI interpretive sets which were read by two readers in consensus, blinded to prior imaging. Lesions were categorized into 13 anatomic regions. Fluorodeoxyglucose / positron emission tomography / computed tomography (FDG-PET/CT) read with full access to prior imaging and clinical records was used as the reference standard. Sensitivity, specificity, and false discovery rate (FDR) were calculated as appropriate and receiver operating characteristic (ROC) curves were constructed. Results: In all, 177 malignant lesions were detected by FDG-PET/CT and distributed in 92 out of 390 scanned anatomic regions. The sensitivity was statistically higher in two out of three sets incorporating DWIBS on a per-lesion basis (66.7%, 63.3%, and 66.7% vs. 57.6%) (P=0.01, P=0.11, and P=0.01, respectively) and in all sets incorporating DWIBS on a per-region basis (75.0%, 75.0%, and 77.2 vs. 66.3%) (P=0.04, P=0.04, and P=0.01, respectively). There was no difference in specificity, FDR, or AUC(ROC). There was no difference between sets containing DWIBS irrespective of the use of a contrast-enhanced sequence. Conclusion: MRI sets containing DWIBS had superior sensitivity. This sensitivity was retained when omitting a contrast-enhanced sequence.

Abstract Purpose: We investigated whether detection of ctDNA after resection of colorectal cancer identifies the patients with the highest risk of relapse and, furthermore, whether longitudinal ctDNA analysis allows early detection of relapse and informs about response to intervention. Experimental Design: In this longitudinal cohort study, we used massively parallel sequencing to identify somatic mutations and used these as ctDNA markers to detect minimal residual disease and to monitor changes in tumor burden during a 3-year follow-up period. Results: A total of 45 patients and 371 plasma samples were included. Longitudinal samples from 27 patients revealed ctDNA postoperatively in all relapsing patients (n = 14), but not in any of the nonrelapsing patients. ctDNA detected relapse with an average lead time of 9.4 months compared with CT imaging. Of 21 patients treated for localized disease, six had ctDNA detected within 3 months after surgery. All six later relapsed compared with four of the remaining patients [HR, 37.7; 95% confidence interval (CI), 4.2–335.5; P < 0.001]. The ability of a 3-month ctDNA analysis to predict relapse was confirmed in 23 liver metastasis patients (HR 4.9; 95% CI, 1.5–15.7; P = 0.007). Changes in ctDNA levels induced by relapse intervention (n = 19) showed good agreement with changes in tumor volume (κ = 0.41; Spearman ρ = 0.4). Conclusions: Postoperative ctDNA detection provides evidence of residual disease and identifies patients at very high risk of relapse. Longitudinal surveillance enables early detection of relapse and informs about response to intervention. These observations have implications for the postoperative management of colorectal cancer patients. Clin Cancer Res; 23(18); 5437–45. ©2017 AACR.

BACKGROUND:In current preoperative fasting guidelines, coffee with milk is still regarded by many as solid food. Evidence on the consequences for gastric volume of adding milk to coffee 2 h before anaesthesia is still weak. OBJECTIVES:The aim of this study was to compare the gastric volume by MRI in healthy volunteers after drinking coffee with and without added milk. DESIGN:A randomised crossover trial where all participants were exposed to three coffee and milk mixtures performed as a noninferiority study with a predefined noninferiority limit of 12 ml. SETTING:Department of Day Surgery and Department of Radiology, Aarhus University Hospital, Aarhus, Denmark. The study was conducted between August 2013 and February 2014. PARTICIPANTS:Total 32 healthy volunteers, aged 18 to 71 years. INTERVENTIONS:The participants fasted for 6 h for solid food, and 2 h before the MRI examination of gastric volume, each participant ingested one of three coffee mixtures: 175 ml coffee, including either 0 or 20 or 50% full fat milk. Each participant was studied by MRI three times separated by a minimum time interval of 2 days. The order of coffee mixture ingested was determined by random allocation. MAIN OUTCOME MEASURE:Gastric volume as measured by MRI. RESULTS:The mean gastric volume for black coffee was 27.8 ml, for coffee with 20% milk 17.9 ml and for coffee with 50% milk 20.6 ml. Compared to black coffee, the gastric volume for 20% milk was significantly decreased with a difference of -10.0 ml (95% confidence interval, -18.2, -1.8), and for 50% milk it was insignificantly decreased, -7.2 ml (95% confidence interval, -17.4, +2.9). The upper confidence interval for the difference in gastric volume between the 'no milk added' group and each 'milk added' group did not reach the noninferiority limit of 12 ml. CONCLUSION:The study provides evidence that adding up to 50% full fat milk to coffee leads to no or only a minimal increase of the gastric volume 2 h later. The results support a liberalisation of policy on the addition of milk to hot drinks before planned anaesthesia. TRIAL REGISTRATION:www.Clinicaltrials.gov identifier: NCT02361632.

BACKGROUND In current preoperative fasting guidelines, coffee with milk is still regarded by many as solid food. Evidence on the consequences for gastric volume of adding milk to coffee 2 h before anaesthesia is still weak. OBJECTIVES The aim of this study was to compare the gastric volume by MRI in healthy volunteers after drinking coffee with and without added milk. DESIGN A randomised crossover trial where all participants were exposed to three coffee and milk mixtures performed as a noninferiority study with a predefined noninferiority limit of 12 ml. SETTING Department of Day Surgery and Department of Radiology, Aarhus University Hospital, Aarhus, Denmark. The study was conducted between August 2013 and February 2014. PARTICIPANTS Total 32 healthy volunteers, aged 18 to 71 years. INTERVENTIONS The participants fasted for 6 h for solid food, and 2 h before the MRI examination of gastric volume, each participant ingested one of three coffee mixtures: 175 ml coffee, including either 0 or 20 or 50% full fat milk. Each participant was studied by MRI three times separated by a minimum time interval of 2 days. The order of coffee mixture ingested was determined by random allocation. MAIN OUTCOME MEASURE Gastric volume as measured by MRI. RESULTS The mean gastric volume for black coffee was 27.8 ml, for coffee with 20% milk 17.9 ml and for coffee with 50% milk 20.6 ml. Compared to black coffee, the gastric volume for 20% milk was significantly decreased with a difference of −10.0 ml (95% confidence interval, −18.2, −1.8), and for 50% milk it was insignificantly decreased, −7.2 ml (95% confidence interval, −17.4, +2.9). The upper confidence interval for the difference in gastric volume between the ‘no milk added’ group and each ‘milk added’ group did not reach the noninferiority limit of 12 ml. CONCLUSION The study provides evidence that adding up to 50% full fat milk to coffee leads to no or only a minimal increase of the gastric volume 2 h later. The results support a liberalisation of policy on the addition of milk to hot drinks before planned anaesthesia. TRIAL REGISTRATION www.Clinicaltrials.gov identifier: NCT02361632.

The serine/threonine kinase Akt (PKB) is activated in response to growth factors, cytokines and other growth promoting stimuli and is involved in the regulation of a number of cellular processes including metabolism, cell growth, proliferation and survival. To study intracellular metabolic effects of left ventricular hypertrophy (LVH) induced by chronic aortic banding in a recently established swine model, protein arrays can be used to analyze changes in cytosolic protein phosphorylation levels such as cell signal transduction and protein kinase pathways. Miniaturized sandwich immunoassays allow the simultaneous analysis of several parameters in a single experiment. Bead-based protein array systems or suspension microarrays are well-established multiplex sandwich immunoassay formats. Cytosolic proteins were extracted from pig hearts. Using the bead-based Luminex system, multiplexed sandwich immunoassays have been developed to analyze the phosphorylated proteins IR[pYpY1162/1163], IGF-1R[pYpY1135 /1136], IRS-1[pS312], Akt[pS473], PRAS40[pT246], p70S6K[pTpS421/424], and GSK-3 beta[pS9], which were measured simultaneously in extracted myocardial tissue homogenates with the Akt Pathway Phospho 7-Plex Panel using a Luminex 100 IS system. Using this assay, tissue homogenates derived from myocardial tissue samples from 28 individual porcine in vivo model experiments in normal hearts (n=17) and LVH hearts (n=11) were analyzed for phosphorylated protein concentrations. Results obtained allowed grouping of myocardial tissue samples into a LVH and a normal group. Two candidate molecules: PRAS40 (normal vs. LVH two-tailed probability P= 0.0022) and GSK-3 beta (P=0.003), had lower concentrations in LVH pigs than in normal animals, suggesting loss of GSK-3 beta inhibitory activity and contributing to speculation of altered insulin sensitivity associated with LVH.

The serine/threonine kinase Akt (PKB) is activated in response to growth factors, cytokines and other growth promoting stimuli and is involved in the regulation of a number of cellular processes including metabolism, cell growth, proliferation and survival. To study intracellular metabolic effects of left ventricular hypertrophy (LVH) induced by chronic aortic banding in a recently established swine model, protein arrays can be used to analyze changes in cytosolic protein phosphorylation levels such as cell signal transduction and protein kinase pathways. Miniaturized sandwich immunoassays allow the simultaneous analysis of several parameters in a single experiment. Bead-based protein array systems or suspension microarrays are well-established multiplex sandwich immunoassay formats. Cytosolic proteins were extracted from pig hearts. Using the bead-based Luminex system, multiplexed sandwich immunoassays have been developed to analyze the phosphorylated proteins IR[pYpY1162/1163], IGF-1R[pYpY1135 /1136], IRS-1[pS312], Akt[pS473], PRAS40[pT246], p70S6K[pTpS421/424], and GSK-3β[pS9], which were measured simultaneously in extracted myocardial tissue homogenates with the Akt Pathway Phospho 7-Plex Panel using a Luminex 100 IS system. Using this assay, tissue homogenates derived from myocardial tissue samples from 28 individual porcine in vivo model experiments in normal hearts (n=17) and LVH hearts (n=11) were analyzed for phosphorylated protein concentrations. Results obtained allowed grouping of myocardial tissue samples into a LVH and a normal group. Two candidate molecules: PRAS40 (normal vs. LVH two-tailed probability P= 0.0022) and GSK-3β (P=0.003), had lower concentrations in LVH pigs than in normal animals, suggesting loss of GSK-3β inhibitory activity and contributing to speculation of altered insulin sensitivity associated with LVH. Keywords: Cardiac hypertrophy, akt/protein kinase B, glycogen synthase (GSK)-3β, proline-rich akt substrate (PRAS40), multiplex analysis, animal model, phosphatidyli-nositol 3-kinase (PI3K) pathway, sandwich immunoassay flow cytometry, sevoflurane anesthesia, IR, IGF-1R, IRS-1, Akt, PRAS40, p70S6K, GSK-3, IR[pYpY1162/1163], IGF-1R[pYpY1135/1136], IRS-1[pS312], Akt[pS473], pT246, GSK-3[pS9], Ambulatory transthoracic ultrasound examinations

Background Echocardiography is the method of choice when one wishes to examine myocardial function. Qualitative assessment of the 2D grey scale images obtained is subjective, and objective methods are required. Speckle Tracking Ultrasound is an emerging technology, offering an objective mean of quantifying left ventricular wall motion. However, before a new ultrasound technology can be adopted in the clinic, accuracy and reproducibility needs to be investigated. Aim It was hypothesized that the collection of ultrasound sample data from an in vitro model could be automated. The aim was to optimize an in vitro model to allow for efficient collection of sample data. Material & Methods A tissue-mimicking phantom was made from water, gelatin powder, psyllium fibers and a preservative. Sonomicrometry crystals were molded into the phantom. The solid phantom was mounted in a stable stand and cyclically compressed. Peak strain was then measured by Speckle Tracking Ultrasound and sonomicrometry. Results We succeeded in automating the acquisition and analysis of sample data. Sample data was collected at a rate of 200 measurement pairs in 30 minutes. We found good agreement between Speckle Tracking Ultrasound and sonomicrometry in the in vitro model. Best agreement was 0.83 ± 0.70%. Worst agreement was -1.13 ± 6.46%. Conclusions It has been shown possible to automate a model that can be used for evaluating the in vitro accuracy and precision of ultrasound modalities measuring deformation. Sonomicrometry and Speckle Tracking Ultrasound had acceptable agreement.