Equipment:
(1) Doppler ultrasound machine with a 10 mHz probe
(2) Small pneumatic cuff (suitable to wrap around the penile shaft base).
(3) Blood pressure cuff for upper arm.
Technique:
(1) The Doppler probe is positioned over a penile artery.
(2) The penile pneumatic cuff is inflated until arterial flow ceases.
(3) The pressure is released until arterial flow can be detected, which is the penile systolic blood pressure.
(4) The brachial artery systolic blood pressure is measured.
penile brachial index =
= (systolic blood pressure in penis) / (systolic blood pressure in brachial artery)
Interpretation:
• Normally the index should be close to 1.
• An index < 0.60 may be associated with vasculogenic impotence.
Limitations:
• The precise artery being measured may be difficult to identify.
• Results of tests performed on a flaccid penis may not apply to the erect phallus.
• The technique is operator dependent and requires some experience to be reliable.
