| 摘要 |
<p>A system for deriving signals representing a selected cross sectional area and volume of a region of interest in tissue. In the preferred embodiment, area and volume of a fluid filled cavity contained in tissue on a real time basis are determined by launching pulses of ultrasonic pressure waves along a plurality of scan lines, detecting the locations along each line that are in fluid, deriving a signal representing the incremental area within fluid that is between adjacent scan lines, deriving a signal representing the cross sectional area of a cavity within a region of interest by summing the incremental areas and deriving a signal representing the volume of the cavity within a region of interest by revolving each incremental area about an axis of the cavity so as to form an incremental volume of revolution and summing the volumes of revolution. The volume of the entire cavity is also attained by deriving the cross sectional area as just described, raising it to the 3/2 power and multiplying it by a coefficient including a function of the ratio of the long axis cross sectional area and short axis cross sectional area. Determination of the locations in fluid in the above calculations are preferably those at which a majority of an odd number of consecutive scan lines at like ranges are in fluid. <IMAGE></p> |
