Choices of venous access, catheter size, and flow rate included the direct supervision of a physician (anesthesiologist and/or neuroradiologist) to provide the safe administration of contrast and aiming to obtain a compact bolus. Automated contrast agent and saline administration was performed using a power injector (Medrad® Spectris Solaris® EP MedRad, Indianola, Pennsylvania) in all examinations. Various peripheral intravenous catheters (18-, 20-, 22-, or 24-ga), locations (hand, arm, or foot), and flow-rates (1–5 mL/s) were used, depending on the age of the patient and the availability/site of venous access. A standard contrast medium dose of 0.1 mmol/kg of body weight was injected followed by a 10–20 mL saline flush. A total of 60 image volumes were acquired, and the first 10 acquisitions were obtained to establish a precontrast baseline before starting the contrast agent injection. To our knowledge, this is the first study to evaluate the feasibility, safety, and quality of DSC-PWI in pediatric patients.ĭSC perfusion MR images were obtained during the first pass of a gadobutrol bolus with 1.5T or 3T MR imaging scanners (Signa Excite and EchoSpeed GE Healthcare, Milwaukee, Wisconsin and Achieva, Philips Healthcare, Best, the Netherlands, respectively) using a gradient-echo EPI sequence (TR = 1500–2250, TE = 35–45 ms, flip angle = 35°–90°, NEX = 1, matrix size = 128 × 128, section thickness = 4–5 mm, gap = 0.4–0.5 mm). We compared the results obtained in children with the DSC quality standards reported in the literature for adults, considered the state of the art. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico, Roma, Foundation Istituto di Ricovero e Cura a Carattere Scientifico, Ca' Granda Ospedale Maggiore Policlinico, Milan) therefore aimed to determine the feasibility and safety of DSC MR perfusion imaging in children and to assess DSC perfusion quality using a “custom child” administration of a standard dose of gadolinium-based contrast agent (GBCA) (0.1 mmol/kg of gadobutrol, Gadovist Bayer Schering Pharma, Berlin, Germany), defined as the use of a power injector at lower flow rates (1–5 mL/s) and by various venous accesses (18–24 ga) and locations (arm, foot, hand), with or without sedation. This prospective, bicenter study (Fondazione Policlinico Universitario A. It is well-known that DSC imaging relies on the rapid acquisition of as many images as possible during the passage of the contrast media through the brain to measure the degree of T2/T2* signal changes with time and that it needs magnetic susceptibility contrast agents to be injected as a narrow bolus by a power injector because high intravascular concentrations of gadolinium are required for T2-weighted magnetic susceptibility effects to dominate image contrast. These limitations discourage the use of DSC-PWI in children, and most pediatric neuroradiologists still prefer manual injection of contrast medium. 2 However, performing DSC MR perfusion in pediatric patients can be challenging due to several technical issues: the need to use a power injector and difficulties in obtaining proper venous access (18–20 ga), reaching a high-flow injection rate (5 mL/s), and guaranteeing patient immobility. 1 The noninvasive character of DSC perfusion, susceptibility for microvascular hemodynamic alterations, short acquisition times, lack of ionizing radiation, and the current widespread availability of MR imaging scanners make DSC-PWI ideally suited for children. DSC-derived cerebral blood volume maps can provide quantitative estimation of relative CBV that can be used to grade gliomas, differentiate brain tumor types, and distinguish tumors from non-neoplastic lesions. Currently, DSC perfusion is routinely used in clinical practice to diagnose, manage, and investigate brain tumors in adult patients. ABBREVIATIONS: FWHM full width at half maximum GBCA gadolinium-based contrast agent PSD percentage of signal dropĭynamic susceptibility-weighted contrast-enhanced perfusion MR imaging provides hemodynamic information complementary to traditional structural MR imaging.
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