Resistance in the artery can be measured through resistance index (RI) [peak systolic velocity (PSV)--end diastolic velocity (EDV)/(PSV)], systolic/diastolic (S/D) ratio (PSV/EDV), and the pulsatility index
(PI) [(PSV--EDV)/mean blood velocity (mV)].
Intraobserver and inter-observer reliability of the pulsatility index
calculated from pulsed Doppler flow velocity waveforms in three fetal vessels.
The values of the pulsatility index
and resistance index were not significantly different between the two groups.
On 2-D-PCD, the Resistance Index (RI=(PSVEDV)/PSV=(peak systolic velocity-end diastolic velocity)/peak systolic velocity), the Pulsatility Index
(PI=(peak systolic velocity-end diastolic velocity)/mean velocity=(PSV-EDV)/TAV), the systolic/diastolic ratio S/D (systolicvelocity/ diastolic velocity) were calculated on three consecutive wave forms which were used to evaluate uterine artery resistance.
Beside the resistance index (RI) and pulsatility index
have also been evaluated, beside IMT, in order to determine a more accurate relationship between cardiovascular dysfunction and pre-eclampsia.
Table 2: Resistive and pulsatility index
of renal artery and aorta of dogs.
Mean pulsatility index
(PI) [greater than or equal to] 1.
5 Peripheral or Disorders miscellaneous * Long axis to short axis (L/S); ** Resistive index (RI); *** Pulsatility index
(PI); ([dagger]) In matted lymph nodes, the border is not sharp.
The mean values and statistical evaluation of first and second trimester uterine artery pulsatility index
(PI) and resistance index (RI) measurements are given in Table 2.
5%, could be achieved by offering the cfDNA test to about 36%, 21%, and 11% of cases identified by first-line screening using the combined test alone, using the combined test with the addition of serum placental growth factor and alpha-fetoprotein, and using the combined test with the addition of placental growth factor, alpha-fetoprotein, and ductus venosus pulsatility index
for veins, respectively," they said.
1) The pulsatility index
(PI) obtained by TTFM is a good indicator of the flow pattern and the quality of the anastomosis, as well as predicting outcomes.
Moreover, physicians will have the option to provide biophysical measurements for their patients - mean arterial pressure (MAP) and uterine artery Doppler pulsatility index
(UtAD-PI) - each increasing the sensitivity of the screen when included in the testing protocol.