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This study aims to explore the relationship between plaque surface morphology and neovascularization using a high temporal and spatial resolution 4D contrast-enhanced MRI/MRA sequence. Twenty one patients with either recent symptoms or a carotid artery stenosis ≥40% were recruited in this study. Plaque surface morphology and luminal stenosis were determined from the arterial phase MRA images. Carotid neovascularization was evaluated by a previously validated pharmacokinetic (PK) modeling approach. K trans (transfer constant) and v p (partial plasma volume) were calculated in both the adventitia and plaque. Image acquisition and analysis was successfully performed in 28 arteries. Mean luminal stenosis was 44% (range 11–82%). Both adventitial and plaque K trans in ulcerated/irregular plaques were significantly higher than smooth plaques (0.079 ± 0.018 vs. 0.064 ± 0.011 min−1, p = 0.02; 0.065 ± 0.013 vs. 0.055 ± 0.010 min−1, p = 0.03, respectively). Positive correlations between adventitial K trans and v p against stenosis were observed (r = 0.44, p = 0.02; r = 0.55, p = 0.01, respectively). This study demonstrates the feasibility of using a single sequence to acquire both high resolution 4D CE-MRA and DCE-MRI to evaluate both plaque surface morphology and function. The results demonstrate significant relationships between lumen surface morphology and neovascularization.

Bevacizumab is a monoclonal antibody against vascular endothelial growth factor (VEGF) widely used in clinical oncology. Bevacizumab is commonly co-adminis- tered with chemotherapy. It is recommended that the first infusion of the antibody last 90 min, the second 60 and all subsequent 30 min. Since there is no clear rationale for the proposed schedule of administration, our study assessed the feasibility of a 30 min initial infusion.Cancer patients eligible for de novo bevacizumab treatment were enrolled. All patients received standard bevacizumab dose of 5, 7.5 or 10 mg/kg according to the indication, diluted in 250 ml normal saline, as a 30-min intravenous infusion.Thirty two patients were enrolled: male 18, female 14, median age 58 years, range 42-78. Oncologic diagnosis: lung cancer 16, colorectal 4, breast 3, ovarian 7, renal 2. All patients tolerated the infusion well. No hypersensitivity reactions were noted. Mean systolic and diastolic blood pressures were 122 and 73 mm/Hg respectively prior to the infusion and 125 and 75 mm/Hg 15 min after the infusion (p=0.3). During the observation period of 1 hour, blood pressure did not change. Transient grade 3 systolic hypertension was noted in 1 patient, with spontaneous regression in 45 min.Rapid administration of bevacizumab in 30 min, rather than the recommended in the package insert 90 min is feasible and safe. Such a practice limits the time of confinement in the treatment area to patients' satisfaction and would result in cost savings by reducing health resource utilization.