Cine MR imaging of valvular heart disease: Display and imaging parameters affect the size of the signal void caused by valvular regurgitation

The effects of display and imaging parameters on the measured size of the signal void representing valvular regurgitation on cine MR imaging were examined. Sixteen patients with valvular regurgitation were studied. Six cine acquisition modes were evaluated in five patients. Echo times (TEs) (8, 12, and 17 msec) and flip angles (30° and 50°) were varied. The variable display parameters were [Z x (blood pool signal intensity - lung signal intensity)] at window width (Z = 0.75, 1.00, 1.25) and (Y x window width + lung signal intensity) at window level (Y = 0.00, 0.25, 0.25, 0.50). The area of the signal void was significantly (p < .01) affected by the window level (2.7 ± 0.8 cm² at Y = 0.00, 4.4 ± 1.1 cm² at Y = 0.25, and 5.6 ± 1.4 cm² at Y = 0.50) and window width (3.6 ± 0.9 cm² at Z = 0.75 and 4.9 ± 1.1 cm² at Z = 1.25). With standardized display parameters, TE influenced the area (3.3 ± 1.1 cm² at 8 msec and 7.8 ± 1.5 cm² at 12 msec; p < .01). Variations in the value of TE and display settings cause differences in the measured area of the regurgitant signal void. Quantification of valvular regurgitation by cine MR imaging requires strict standardization of display and imaging parameters.