This document discusses the radiologist's role in evaluating ambiguous genitalia. It begins with an overview of reproductive system development and sexual differentiation. It then classifies disorders of sex development (DSDs) and discusses various types of male pseudohermaphroditism. It outlines the multidisciplinary workup and emphasizes the role of ultrasound, MRI, and fluoroscopy in evaluation. It notes imaging findings for different internal reproductive structures and DSDs. It concludes by discussing risks of neoplasms associated with different DSDs.
8. Classification
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).
22. Work-up
coordinated medical team that includes a
pediatric endocrinologist, geneticist,
urologist, and radiologist
to ensure timely diagnosis and proper
management.
23.
24. Role of imaging
US is the primary modality for evaluation of
the internal reproductive organs,
whereas genitography and voiding
cystourethrography are used for evaluation
of urethral and vaginal tracts and fistulas.
MR imaging may serve as a problem-
solving modality for clarifying the internal
anatomy and searching for internal
gonads.
30. Fluoroscopy-Genitography
It is important to examine
all perineal orifices and insert the catheter for
a short distance into each orifice to preserve its
morphologic appearance.
A good maneuver is to
fill the balloon of an 8-F Foley catheter outside
the body and insert just the distal tip, performing
a retrograde injection.
34. Role of MRI
Ectopic gonads, testes, and noncystic
immature ovaries have intermediate
signal intensity on T1-weighted MR
images and high signal intensity with an
intermediate-signal-intensity outer rim on
T2-weighted images
37. Streak gonads are difficult to detect and can
be seen as low-signal-intensity stripes on
T2-weighted images .
High-signal-intensity foci in streak gonads
could represent neoplastic change .
39. Risk of Neoplasm
Because 20%–30% of children with XY PGD
and 15%–20% with MGD develop a gonadal
neoplasm within the 1st or 2nd decade of life,
streak gonads should be removed .
The presence of a well-defined part of the Y chromosome
(GBY [gonadoblastoma locus on the
Y chromosome]) is implicated in the development
of malignant neoplasms in dysgenetic
gonads .
Gonadoblastoma is the most common
tumor, usually arising from dysgenetic
intraabdominal gonads
40. Attention
The presence of an echogenic focus at
US associated with the pelvic organs or
found in ectopic gonadal tissue within the
inguinal canals or labioscrotal folds should
be regarded with suspicion, since
gonadoblastomas often calcify.
42. Wilm’s Tumour
There is increased risk of developing
Wilms tumor, particularly when XY gonadal
dysgenesis is associated with
glomerulopathy in
Drash syndrome
43. Breast Cancer
Risk factors for male breast cancer include
conditions with increased estrogen
exposure, such as advanced age,
cryptorchidism, testicular injury,
Klinefelter’s syndrome, and liver
dysfunction.