Doppler Resistance Index Calculator

Formula

The formula to calculate the Doppler Resistance Index (RI) is:

\[ \text{RI} = \frac{\text{PSV} - \text{EDV}}{\text{PSV}} \]

Where:

RI – The Resistance Index.
PSV – The Peak Systolic Velocity (cm/s).
EDV – The End Diastolic Velocity (cm/s).

Definition

Doppler Resistance Index (RI): A measure used in medical ultrasound imaging to quantify the resistance to blood flow in various organs and vessels.
Peak Systolic Velocity (PSV): The maximum blood flow velocity during systole.
End Diastolic Velocity (EDV): The blood flow velocity at the end of diastole.

Example

Let's say the Peak Systolic Velocity (PSV) is 120 cm/s and the End Diastolic Velocity (EDV) is 40 cm/s. Using the formula:

\[ \text{RI} = \frac{120 - 40}{120} = \frac{80}{120} \approx 0.67 \]

So, the Doppler Resistance Index is approximately 0.67.

Extended information about "Doppler-Resistance-Index-Calculator"

Resistive Index in Doppler

Definition: The resistive index (RI) is a measure used in Doppler ultrasound to assess the resistance to blood flow in vessels.

Formula: \( RI = \frac{PSV - EDV}{PSV} \)

\( RI \): Resistive Index
\( PSV \): Peak Systolic Velocity
\( EDV \): End-Diastolic Velocity

Example: \( RI = \frac{120 - 40}{120} \)

PSV: 120 cm/s
EDV: 40 cm/s

Indice de Résistance Doppler

Definition: L'indice de résistance (IR) est une mesure utilisée en échographie Doppler pour évaluer la résistance au flux sanguin dans les vaisseaux.

Formula: \( IR = \frac{VSM - VDF}{VSM} \)

\( IR \): Indice de Résistance
\( VSM \): Vitesse Systolique Maximale
\( VDF \): Vitesse Diastolique Finale

Example: \( IR = \frac{150 - 50}{150} \)

VSM: 150 cm/s
VDF: 50 cm/s

Doppler Velocity Index Calculator

Definition: The Doppler Velocity Index (DVI) is used to assess the function of aortic prosthetic valves and screen for valve obstruction.

Formula: \( DVI = \frac{LVOT_{velocity}}{AV_{velocity}} \)

\( DVI \): Doppler Velocity Index
\( LVOT_{velocity} \): Left Ventricular Outflow Tract Velocity
\( AV_{velocity} \): Aortic Valve Velocity

Example: \( DVI = \frac{1.2}{4.0} \)

LVOT_{velocity}: 1.2 m/s
AV_{velocity}: 4.0 m/s

Formula Indice de Resistencia Doppler

Definition: El índice de resistencia (IR) es una medida utilizada en ecografía Doppler para evaluar la resistencia al flujo sanguíneo en los vasos.

Formula: \( IR = \frac{VSM - VDF}{VSM} \)

\( IR \): Índice de Resistencia
\( VSM \): Velocidad Sistólica Máxima
\( VDF \): Velocidad Diastólica Final

Example: \( IR = \frac{130 - 60}{130} \)

VSM: 130 cm/s
VDF: 60 cm/s

CP Ratio Doppler Calculator

Definition: The Cerebroplacental Ratio (CPR) is an obstetric ultrasound tool used to predict adverse pregnancy outcomes.

Formula: \( CPR = \frac{MCA_{PI}}{UA_{PI}} \)

\( CPR \): Cerebroplacental Ratio
\( MCA_{PI} \): Middle Cerebral Artery Pulsatility Index
\( UA_{PI} \): Umbilical Artery Pulsatility Index

Example: \( CPR = \frac{1.5}{0.8} \)

MCA_{PI}: 1.5
UA_{PI}: 0.8

Resistive Index Renal Artery Doppler

Definition: The renal arterial resistive index (RI) is a sonographic index of intrarenal arteries used to assess renal function.

Formula: \( RI = \frac{PSV - EDV}{PSV} \)

\( RI \): Resistive Index
\( PSV \): Peak Systolic Velocity
\( EDV \): End-Diastolic Velocity

Example: \( RI = \frac{100 - 30}{100} \)

PSV: 100 cm/s
EDV: 30 cm/s

Relativistic Doppler Effect Calculator

Definition: The relativistic Doppler effect describes the change in frequency or wavelength of light due to the relative motion of the source and observer at relativistic speeds.

Formula: \( f' = f \sqrt{\frac{1 + \frac{v}{c}}{1 - \frac{v}{c}}} \)

\( f' \): Observed Frequency
\( f \): Emitted Frequency
\( v \): Relative Velocity
\( c \): Speed of Light

Example: \( f' = 500 \sqrt{\frac{1 + \frac{0.1}{1}}{1 - \frac{0.1}{1}}} \)

f: 500 Hz
v: 0.1c

Doppler Velocity Index vs Dimensionless Index

Definition: The Doppler Velocity Index (DVI) and Dimensionless Index (DI) are used to assess aortic stenosis severity.

Formula: \( DI = \frac{LVOT_{VTI}}{AV_{VTI}} \)

\( DI \): Dimensionless Index
\( LVOT_{VTI} \): Left Ventricular Outflow Tract Velocity-Time Integral
\( AV_{VTI} \): Aortic Valve Velocity-Time Integral

Example: \( DI = \frac{20}{80} \)

LVOT_{VTI}: 20 cm
AV_{VTI}: 80 cm