Prader balls

I've been trying to put together a case report on the use of testosterone replacement therapy (TRT).

Many references note the well known side effect of TRT-testicular atrophy.

Sources note that treatment should be stopped if/when testicles decrease to a size of 5 ml's or less.

I wasn't sure how to measure or even estimate this. I was more accustomed to thinking in terms of testicular size in regards to cm's.

Thankfully, a Swiss pediatric endocrinologist, Andrea Prader, came up with an orchidometer, or Prader's balls, in 1966 to help clinicians.

It's a string of wooden or plastic balls that vary from 1 ml to 25 ml's used to help estimate testicular size.

It's also been called the "Endocrine Rosary."