detention rockfill dams are an easy and common tool for flood control. due to their coarse pores, the flow in void spaces is turbulent and non-darcy. different relationships introduced by researchers are used to define the hydraulics of the flow within the rockfill materials. the present research is aimed at gaining a better understanding of the differ-ence among these relationships and the sou...

We report a patient with profound hypovolemia who developed dynamic left ventricular outflow tract obstruction and severe mitral regurgitation. Both the outflow tract obstruction and mitral regurgitation resolved with volume replacement. Unlike previous reports of dynamic left ventricular outflow obstruction and mitral regurgitation, the degree of mitral regurgitation was severe. Possible mecha...

A 96-year-old woman developed hemiparesis 2 weeks after orthopedic surgery. Magnetic resonance imaging revealed multiple cerebral infarctions in the bilateral hemisphere. Transthoracic echocardiography revealed a mobile structure attached to the anterior mitral leaflet that protruded toward the left ventricular outflow tract. The structure was identified as an accessory mitral valve. Doppler ec...

A 46 year old man was found to have left ventricular outflow obstruction caused by a blood-filled cyst attached to the anterior papillary muscle of the mitral valve. It was successfully excised.

Accessory mitral valve tissue, a rare cause of left ventricular outflow tract obstruction, can be difficult to diagnose preoperatively and confusing even at surgery. The reported case illustrates how preoperative evaluation can be made using two-dimensional echocardiography combined with Doppler flow analysis. The intraoperative technique for removing the accessory tissue without causing damage...

A hydraulic fluid impedance plot is produced by plotting instantaneous differential pressure against phasic blood flow across a vascular segment. This simple plot quantitatively and compactly describes the changes in flow resistance (impedance) throughout the entire cardiac cycle. Impedance plots were obtained before and after corrective surgery in patients with a variety of left ventricular ou...

PURPOSE To study the effect on outflow facility and outflow resistance of a nitinol microstent implanted into Schlemm's canal. METHODS Using a constant pressure perfusion method, outflow facility and outflow resistance were measured in 26 pairs of dissected anterior segments from donated human eyes. Measurements were made at perfusion pressures of 10, 20, 30 and 40 mm Hg. The Hydrus Microsten...

PURPOSE To determine the day and night differences in intraocular pressure (IOP), aqueous flow, outflow facility, uveoscleral outflow, and central corneal thickness (CCT) in juvenile and adult rabbits. METHODS Studies were performed on twelve 3-month-old and ten 12-month-old male New Zealand White rabbits. Daytime measurements were made between 9 AM (3 hours after lights on) and 3 PM, and nig...