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Improved detection of hypervascular liver lesions with CAIPIRINHA-Dixon-TWIST-volume-interpolated breath-hold examination.
Kazmierczak, PM, Theisen, D, Thierfelder, KM, Sommer, WH, Reiser, MF, Notohamiprodjo, M, Nikolaou, K
Investigative radiology. 2015;(3):153-60
Abstract
OBJECTIVES The aim of this study was to assess the diagnostic performance of a dynamic, multiphasic contrast-enhanced volume-interpolated sequence with advanced parallel imaging techniques, Dixon fat saturation, and view sharing with 5 hepatic arterial subphases for the detection of focal liver lesions. MATERIALS AND METHODS Twenty-four consecutive patients (13 females, 11 males; mean [SD] age, 58 [15] years) with focal liver lesions were included in this prospective study. The examination was performed at a 3-T magnetic resonance imaging system (MAGNETOM Skyra; Siemens Healthcare, Erlangen, Germany). Five dynamic arterial subphases with a temporal resolution of 2.6 seconds, starting 17 seconds after injection of the hepatobiliary contrast agent gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Eovist; Bayer HealthCare, Leverkusen, Germany), were acquired using an accelerated parallel imaging volume-interpolated sequence with view sharing (multiarterial controlled aliasing in parallel imaging results in higher acceleration-Dixon-time-resolved angiography with interleaved stochastic trajectories-volumetric interpolated breath-hold examination [MA-CDT-VIBE]). The fourth of the 5 arterial acquisition phases (ie, at 24.8 seconds after the start of contrast agent injection) was considered the equivalent of a standard hepatic arterial phase (equivalent standard arterial phase [ESAP]). The diagnostic value of all 5 dynamic arterial phases for the detection of focal liver lesions, as compared with the single ESAP, was judged in 2 independent consensus readings. The 2 consensus reading groups were blinded to each others' results. The complete, comprehensive multisequence magnetic resonance imaging examination, including T1-weighted, T2-weighted, and multiphasic contrast-enhanced sequences, served as the standard of reference for lesion detection. RESULTS Forty-six percent of the patients (11/24) had hypervascular lesions. In 79 % of all patients (19/24), the best arterial parenchymal contrast of one of the MA-CDT-VIBE acquisition phases was considered better than that of the ESAP. In one third of all cases (8/24 for the first and 6/24 for the second consensus reading), MA-CDT-VIBE showed an improved lesion detection rate compared with ESAP, especially in hypervascular lesions (4/11, representing 36% of all patients with hypervascular lesions). There was a high degree of interrater agreement between the 2 consensus reading groups (the Cohen κ, 0.71-1.00; P < 0.001). CONCLUSIONS Compared with a standard hepatic arterial phase, MA-CDT-VIBE with 5 hepatic arterial subphases demonstrated greater diagnostic accuracy for the detection of hypervascular focal liver lesions and provided a robust and optimized hepatic arterial acquisition phase.
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Pilot study of DCE-MRI to predict progression-free survival with sorafenib therapy in renal cell carcinoma.
Flaherty, KT, Rosen, MA, Heitjan, DF, Gallagher, ML, Schwartz, B, Schnall, MD, O'Dwyer, PJ
Cancer biology & therapy. 2008;(4):496-501
Abstract
BACKGROUND The investigation of angiogenesis inhibitors is of particular interest in renal cell carcinoma (RCC), in which dysregulated blood vessel formation has been correlated with shortened survival. Sorafenib is a novel RAF and VEGF receptor tyrosine kinase inhibitor. We conducted this study to (a) determine if sorafenib is anti-angiogenic, and (b) to relate anti-angiogenic effect to outcome. RESULTS Four patients achieved partial response by WHO criteria (ORR 24%). Median time to progression (TTP) was 12.9 months. K(trans) decreased significantly during treatment with sorafenib (60.3% decline, 95% CI 46.1-74.6%). The percent decline in K(trans) and change in tumor size by CT scan were significantly associated with progression-free survival (p = 0.01 and 0.05, respectively). In addition, K(trans) at baseline was also significantly associated with progress-free survival (p = 0.02). PATIENTS AND METHODS Seventeen patients with metastatic RCC underwent dynamic-contrast enhanced magnetic resonance imaging (DCE-MRI). DCE-MRI was used to calculate the gadolinium exchange constant between blood and tumor interstitial tissue, K(trans). CONCLUSIONS In patients with RCC, inhibition of tumor vascular permeability by sorafenib was associated with improved outcome. Moreover, baseline tumor vascular permeability, expected to be a poor prognosis factor, was a predictive marker of favorable response to therapy.
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Optimizing scan delays of fixed duration contrast injection in contrast-enhanced biphasic multidetector-row CT for the liver and the detection of hypervascular hepatocellular carcinoma.
Kanematsu, M, Goshima, S, Kondo, H, Nishibori, H, Kato, H, Yokoyama, R, Miyoshi, T, Hoshi, H, Onozuka, M, Moriyama, N
Journal of computer assisted tomography. 2005;(2):195-201
Abstract
OBJECTIVE To determine the optimal scan delay required for fixed duration contrast injection in contrast-enhanced biphasic multidetector-row CT for the liver and the detection of hypervascular hepatocellular carcinoma (HCC). METHODS CT images (2.5-mm collimation, 5-mm thickness with no intersectional gap) were obtained after an intravenous bolus injection of 2 mL/kg of nonionic iodine contrast material (300 mg I/mL) for a fixed 30-second injection in 206 patients, who were prospectively randomized into four groups, for which scans were initiated at -5, 15, and 35 seconds; at 0, 20, and 40 seconds; at 5, 25, and 45 seconds; or at 10, 30, and 50 seconds for the first (acquisition time: 4.3 seconds), second (4.3 seconds), and third (9.1 seconds) phases, respectively, after the completion of contrast injection. Mean CT values (HU) of the abdominal aorta, spleen, main portal veins, liver parenchyma, and hepatic veins were measured. Increases in CT values between pre- and post-contrast CTs (DeltaHU) for the organs, and spleen-to-liver and HCC-to-liver contrast differences (deltaHU) were assessed. RESULTS Abdominal aorta reached 273-301 DeltaHU at -5 to 10 seconds with a peak (301 DeltaHU) at 5 seconds. Spleen peaked (115 DeltaHU) at 10 seconds. Liver parenchyma were enhanced weakly (11-34 DeltaHU) at -5 to 10 seconds, exceeded 50 DeltaHU at 20 seconds, peaked (61 DeltaHU) at 30 seconds, and then plateaued (54-58 DeltaHU) at 35-50 seconds. Hepatic veins were enhanced weakly (14-37 DeltaHU) at -5 to 10 seconds, and reached 67 DeltaHU at 15 seconds. Spleen-to-liver (65-69 deltaHU) and HCC-to-liver (31-34 deltaHU) contrast differences were highest at 5-10 seconds. Qualitative results corresponded well with quantitative results. CONCLUSIONS For the detection of hypervascular HCCs, the optimal scan delay after a 30-second contrast injection of the hepatic arterial phase, was found to range from 5 to 10 seconds, and that of the portal venous phase was 35 seconds or somewhat longer.
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Austrian Moderate Altitude Study (AMAS 2000) - fluid shifts, erythropoiesis, and angiogenesis in patients with metabolic syndrome at moderate altitude (congruent with 1700 m).
Gunga, HC, Fries, D, Humpeler, E, Kirsch, K, Boldt, LE, Koralewski, E, Johannes, B, Klingler, A, Mittermayr, M, Röcker, L, et al
European journal of applied physiology. 2003;(6):497-505
Abstract
It was hypothesized that subjects with metabolic syndrome (hypertension, obesity, hyperlipidemia, diabetes mellitus): (1) develop measurable peripheral edema at moderate altitude and (2) might show differences on erythropoiesis, iron status and vascular endothelial growth factor (VEGF) in comparison to healthy subjects during and after a long-term stay (3-week exposure) at moderate altitude (congruent with 1700 m). Twenty-two male subjects with metabolic syndrome were selected. Baseline investigations (t1) were performed in Innsbruck (500 m). All participants were transferred by bus to 1700 m (Alps) and remained there for 3 weeks with examinations on day 1 (after the first night at altitude, t2), day 4 (t3), day 9 (t4) and day 19 (t5). After returning to Innsbruck, post-altitude examinations were conducted after 7-10 days (t6) and 6-7 weeks (t7), respectively. Body mass was decreased from t1 to t7 (P<0.01). Total body water was decreased at t2 (P<0.01), returned to control level (t3, t4), and was found elevated at t7 (P<0.01). Lean body mass did not change, but body fat decreased during the study (P<0.01). Tissue thickness at the forehead decreased during and after altitude exposure (P<0.01), whereas tissue thickness at the tibia did not alter. Erythropoietin (EPO) was elevated as early as t2 and remained increased until t5. Reticulocyte count was increased at t3 and remained above pre-altitude values. VEGF levels were unchanged. After a 3-week exposure to moderate altitude, patients with metabolic syndrome had reduced their body mass, mainly because of a reduction in body fat. The moderate altitude was found to stimulate erythropoiesis in these patients but this was not sufficient to increase serum VEGF concentration.
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Low glucose degradation products dialysis solution modulates the levels of surrogate markers of peritoneal inflammation, integrity, and angiogenesis: preliminary report.
Kim, YL, Do, J, Park, SH, Cho, K, Park, J, Yoon, K, Cho, DK, Lee, EG, Kim, IS
Nephrology (Carlton, Vic.). 2003;:S28-32
Abstract
The presence of glucose degradation products (GDPs) in peritoneal dialysis (PD) fluids has many adverse effects, namely clinically significant abdominal pain or discomfort during infusion, inhibition of cell proliferation, impairment of inflammatory cell function, cytotoxicity, and the induction of vascular endothelial growth factor (VEGF). In a prospective, randomized, controlled trial comparing a low GDP PD solution (pH 7.0, two compartment bag: low GDP) to conventional PD solution (pH 5.5: high GDP), the overnight dialysate levels of the markers of inflammation/wound healing (hyaluronic acid (HA)), mesothelial cell mass/membrane integrity (cancer antigen 125 (CA125)), and angiogenesis (VEGF) were assessed over a 12-month period. Twenty-six newly commencing continuous ambulatory peritoneal dialysis (CAPD) patients were randomly assigned to either the Low GDP group (n = 16) or the High GDP group (n = 10). Standard peritoneal permeability analysis for membrane transport characteristics and dialysis adequacy with nutritional status (serum albumin, nPCR) were evaluated at 1, 6, and 12 months. In patients treated with high GDP solution, there was significant increase in VEGF with time (time = 1 month, 67.2 +/- 10.8; time = 6 months, 189.8 +/- 90.2; and time = 12 months, 169.3 +/- 83.1 pg/mg of protein; P < 0.05). There was no significant change of VEGF with time in the low GDP group. Significantly higher concentrations of CA125 (65.5 +/- 10.4 vs. 19.7 +/- 2.6 at 1 month, P < 0.0001; 66.6 +/- 9.8 vs. 29.7 +/- 5.0 at 6 months, P < 0.01; 68.7 +/- 10.5 vs. 30.7 +/- 10.0 U/mL at 12 months, P < 0.01) and lower concentrations of HA (114.6 +/- 18.8 vs. 254.3 +/- 69.2 at 1 month, P < 0.05; 417.5 +/- 57.2 vs. 1277.5 +/- 367.9 ng/mg of protein at 12 month, P < 0.05) were observed in the low GDP group compared with the high GDP group. In conclusion, continuous therapy with the low GDP solution modulates the levels of surrogate markers of peritoneal inflammation, integrity and angiogenesis. The results strongly suggest that the use of a low GDP solution would be beneficial to maintain the function and structural integrity of the peritoneal membrane.