Orchidometer 223988 188300693 2008-02-01T02:47:14Z 88.134.39.116 An '''orchidometer''' is a [[medical instrument]] used to measure the [[volume]] of the [[testicle]]s. The orchidometer was introduced in [[1966]] by pediatric [[endocrinologist]] Prof. Dr. Dr. hc. Andrea Prader of the [[University of Zurich]]. It consists of a string of twelve numbered wooden or plastic beads of increasing size from about 1 to 25 [[millilitre]]s. [[Physician|Doctor]]s sometimes informally refer to them as "Prader's balls", "the medical worry beads", or the "endocrine rosary." The beads are compared with the testicles of the patient, and the volume is read off the bead which matches most closely in size. Prepubertal sizes are 1–3 ml, pubertal sizes are considered 4 ml and up and adult sizes are 12–25 ml. The orchidometer can be used to accurately determine size of testes. Discrepancy of testicular size with other parameters of maturation can be an important clue to various diseases. Small testes can indicate either primary or secondary [[hypogonadism]]. Testicular size can help distinguish between different types of [[precocious puberty]]. Since testicular growth is typically the first physical sign of true puberty, one of the most common uses is as confirmation that puberty is beginning in a boy with [[delayed puberty|delay]]. Large testes ([[macroorchidism]]) can be a clue to one of the most common causes of mental retardation, [[fragile X syndrome]]. Professor Stephen Shalet, a leading [[endocrinologist]] who works for the [[Christie Hospital]] in [[Manchester]], is reported to have told ''[[The Observer]]'', "Every endocrinologist should have an orchidometer. It's his [[stethoscope]]." == Further reading == * Prader, A., "Testicular size: Assessment and clinical importance", ''Triangle'', 1966, vol. 7, pp. 240 - 243 * Taranger, J., Engström, I., Lichtensten, H., Svenberg-Redegren, I., "Somatic Pubertal Development", ''Acta Pediatr. Scand.'' Suppl. 1976, vol. 258, pp. 121 - 135 ==External links== * "[http://www.geocities.com/toonpoontycoon/Orchidometer.pdf Orchidometer]" - A printable paper orchidometer in PDF format. [[Category:Andrology]] [[Category:Medical equipment]] [[Category:Dimensional instruments]] [[pl:Orchidometr]]