Imaging of Ambiguous Genitalia: Classification and Diagnostic Approach1 CME FEATURE
See accompanying test at http:// www.rsna.org /education /rg_cme.html
Govind B. Chavhan, MD, DNB • Dimitri A. Parra, MD • Kamaldine Oudjhane, MD • Stephen F. Miller, MD • Paul S. Babyn, MD • Joao L. Pippi Salle, MD Disorders of sex development (DSDs) are congenital conditions in which the development of chromosomal, gonadal, or anatomic sex is atypical. DSDs can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries); male pseudohermaphroditism (46,XY with two testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis, either mixed (a testis and a streak gonad) or pure (bilateral streak gonads). Imaging plays an important role in demonstrating the anatomy and associated anomalies. Ultrasonography is the primary modality for demonstrating internal organs; genitography is used to assess the urethra, vagina, and any fistulas or complex tracts; and magnetic resonance imaging is used as an adjunct modality to assess for internal gonads and genitalia. Early and appropriate gender assignment is necessary for healthy physical and psychologic development of children with ambiguous genitalia. Gender assignment can be facilitated with a team approach that involves a pediatric endocrinologist, geneticist, urologist, psychiatrist, social worker, neonatologist, nurse, and radiologist, allowing timely diagnosis and proper management. ©
LEARNING OBJECTIVES FOR TEST 3
After reading this article and taking the test, the reader will be able to: ■ List
broad categories of disorders of sex development that cause ambiguous genitalia. the clinical and imaging features of various conditions that cause ambiguous genitalia. a diagnostic approach for the evaluation of children with ambiguous genitalia and appropriate gender assignment.
RSNA, 2008 • radiographics.rsnajnls.org
TEACHING POINTS See last page
Abbreviations: CAH = congenital adrenal hyperplasia, CAI = complete androgen insensitivity, DSD = disorder of sex development, MGD = mixed gonadal dysgenesis, MIS = müllerian inhibiting substance, PGD = pure gonadal dysgenesis RadioGraphics 2008; 28:1891–1904 • Published online 10.1148/rg.287085034 • Content Codes: 1 From the Departments of Diagnostic Imaging (G.B.C., D.A.P., K.O., S.F.M., P.S.B.) and Pediatric Urology (J.L.P.S.), Hospital for Sick Children and University of Toronto, 555 University Ave, Toronto, ON, Canada M5G 1X8. Recipient of a Certificate of Merit award for an education exhibit at the 2007 RSNA Annual Meeting. Received February 21, 2008; revision requested April 4 and received May 28; accepted June 3. All authors have no financial relationships to disclose. Address correspondence to G.B.C. (e-mail: firstname.lastname@example.org).
RG ■ Volume 28 • Number 7
Figure 1. Chart illustrates normal reproductive system development. MIS = müllerian inhibiting substance, TDF = testis determining factor.
The birth of a baby with ambiguous genitalia can cause great apprehension for the family as well as for healthcare providers. Timely and appropriate gender assignment is necessary for healthy physical and psychologic development of the child with ambiguous genitalia. Work-up of these patients is best accomplished with a coordinated medical team that includes a pediatric endocrinologist, geneticist, urologist, and radiologist to ensure timely diagnosis and proper management. Imaging plays an important role in accurately demonstrating the anatomy and possible effects on other organs...