Algorithm for the laboratory diagnosis of androgen deficiency in the male. T, testosterone; LH, luteinizing hormone; FSH, follicle-stimulating hormone; TRUS Bx, transrectal ultrasound and prostate biopsy; MRI, magnetic resonance imaging; CT, computed tomography scan. Source: Chapter 45. The Aging Male, Smith & Tanagho's General Urology, 18e Citation: McAninch JW, Lue TF. Smith & Tanagho's General Urology, 18e; 2013 Available at: http://accessmedicine.mhmedical.com/DownloadImage.aspx?image=/data/books/mcan18/mcan18_c045f005.png&sec=41094930&BookID=508&ChapterSecID=41088122&imagename= Accessed: October 26, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved