What indicators are taken into account in dopplerometry?
When decoding dopplerometry, prescribed for pregnant women, many women are interested in the indicators of the norm. Without waiting for the doctor's conclusion, future mothers try to figure out the result of the research themselves. Do not do this, because when analyzing the answer, many factors must be taken into account.
To assess the blood flow during dopplerometry in pregnant women take into account the following indicators:
- Resistive index (IR) - is the difference between systolic (during cardiac contraction) and diastolic (relaxation) rates of blood flow;
- pulse index (PI) - the ratio of the difference between systolic and diastolic velocity to the cardiac value of the speed of the diagnosed vessel;
- systolic-diastolic ratio (SDO) - the ratio of blood flow velocity through the vessels to the phase of systole and diastole.
How is the evaluation of the results of dopplerometry?
Each of the above dopplerometry indicators for pregnant women is assessed separately. In this case, the diagnosis of the arteries is performed alternately and the blood flow in the uterine, umbilical, carotid and cerebral arteries, as well as in the aorta, is taken into account.
The norm of dopplerometry indicators for pregnant women is constantly changing, and depends on the period of pregnancy.
Thus, the SDO in the uterine arteries, starting from the 20th week until the moment of birth, is 2.0.
LAD, and with it PI, IR in the arteries of the umbilical cord decrease slowly and gradually throughout the 2 nd half of pregnancy.
The SDO for weeks changes as follows:
- 20-23 week - 0,61-0,80;
- 24-29 week - 0.57-0.77;
- 30-33 week - 0.519-0.74;
- 34-37 week - 0,49-0,7;
- The 38-41 week is 0.40-0.68.
The resistive index, in turn, also changes during the gestation:
- 20-23 week - 3.8-3.95;
- 24-29 week - 3,3-3,5;
- 30-33 week - 2,5-2,8;
- 34-37 week - 2.4-2.6;
- 38-41 week - 2,18-2,22.
However, every future mother should understand that the given indicators are taken into account in conjunction with the features of the course of pregnancy. Therefore, in no case should it be necessary to decipher the values obtained as a result of doplerometry independently .