What penile/brachial index value defines a normal result?

• A. 0.75 or greater
• B. 0.65-0.74
• C. <0.65
• D. 0.85-1.0

Answer: (A)

The penile-brachial index compares penile systolic pressure to brachial systolic pressure to gauge arterial inflow to the penis. A normal result is a penile-to-brachial ratio of 0.75 or higher, indicating adequate penile arterial perfusion. Ratios in the 0.65–0.74 range are borderline and may reflect mild arterial compromise, while values below 0.65 suggest significant arterial insufficiency that could contribute to erectile dysfunction. Values in the upper-normal range, such as 0.85–1.0, are still normal, but the standard cutoff used to define a normal PBI is 0.75 or greater. Interpretation should consider measurement technique and patient hemodynamics, since these can influence the ratio.