Jonathan M. Rubin

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PURPOSE The authors present a preliminary report to demonstrate a new color Doppler (CD) ultrasonography (US) technique called power Doppler (PD), which displays the total integrated Doppler power in color, and to compare PD with CD imaging, which generally displays an estimate of the mean Doppler frequency shift. MATERIALS AND METHODS Two standard(More)
Timing of cellular and subcellular events contributes to spiking-induced modification of synapses in a variety of ways. Initially, the timing of presynaptic and postsynaptic action potentials must be translated into signals that can initiate intracellular processes. Recent experimental and computational findings suggest that the spatiotemporal details of(More)
The resistive index (RI), calculated from the duplex Doppler waveform, was compared with clinical and laboratory findings and the results of renal biopsy in 41 patients with nonobstructive (medical) renal disease. Kidneys with active disease in the tubulointerstitial compartment had a mean RI of 0.75 +/- 0.07. This was statistically significantly different(More)
It has recently been suggested that the resistive index (RI) in native kidneys of healthy children is age dependent; however, this relationship has not been completely defined or explained. In 110 kidneys in 71 healthy children aged newborn to 11 years, RIs were determined from peripheral sites (presumed to be arcuate, cortical, or distal interlobar(More)
Ultrasonography (US) of the native kidneys is commonly requested for acute renal failure (ARF), although in most cases the examination results are negative. To detect changes in the Doppler waveform associated with ARF and determine whether Doppler US can provide significant diagnostic information not available with standard US, 91 patients with ARF were(More)
Distinction of the obstructed from the nonobstructed dilated renal collecting system is a difficult problem often requiring interventional procedures and pressure measurements. The authors prospectively performed duplex Doppler ultrasound (US) evaluations in 21 kidneys (obstructed, n = 14; nonobstructed, n = 7) immediately before percutaneous nephrostomy.(More)
PURPOSE To compare power Doppler sonography with color Doppler sonography in the depiction of normal intrarenal vasculature. MATERIALS AND METHODS Twenty kidneys in 10 healthy, nonobese subjects were studied with color Doppler and power Doppler sonography at 3.5 MHz and a pulse repetition frequency of 800 Hz. The color gain was increased until "noise"(More)
The Society of Radiologists in Ultrasound convened a panel of specialists from radiology, hepatology, pathology, and basic science and physics to arrive at a consensus regarding the use of elastography in the assessment of liver fibrosis in chronic liver disease. The panel met in Denver, Colo, on October 21-22, 2014, and drafted this consensus statement.(More)
OBJECTIVE To examine the efficacy and tolerability of guanfacine extended release (GXR) administered in the morning or evening in children with attention-deficit/hyperactivity disorder (ADHD). METHOD In this multicenter, double-blind, placebo-controlled, dose-optimization study, children 6 to 12 years of age with ADHD were randomized to receive GXR (1-4(More)
Because animal studies have shown that renal obstruction increases renal vascular resistance, we theorized that obstruction would change the Doppler waveform. We studied the value of the resistive index (RI) calculated from the duplex Doppler waveform to distinguish between obstructive and nonobstructive pyelocaliectasis in 229 kidneys in 133 patients. The(More)