Diagnostic ultrasound ( PDFDrive )

478 PART II Abdominal and Pelvic Sonography
IIR
IC
IEA
Long-axis right internal
inguinal ring and inguinal canal
Internal
inguinal
ring
Inferior
epigastric artery
FIG. 13.12 Indirect Inguinal Hernia. Long-axis view shows that neck of the hernia lies in the internal inguinal ring (IIR), which lies superior
and lateral to the proximal inferior epigastric artery (IEA). Hernia sac then courses horizontally in an inferomedial direction within the inguinal canal
(IC). Indirect inguinal hernias always pass supericial to the IEA.
A
A
B
B
FIG. 13.13 Indirect Inguinal Hernias: Two Types. (A) Sliding type. The neck (arrows) is as wide as or wider than the fundus (arrowheads),
with loss of the angle between the internal inguinal ring and inguinal canal. Sliding hernias usually contain intraperitoneal contents and are reducible.
(B) Nonsliding type. The neck (arrows) is narrow in comparison to the fundus (arrowheads), and the nearly 90-degree angle between the internal
inguinal ring and inguinal canal is preserved. Nonsliding hernias usually contain only properitoneal fat and are nonreducible. They have often been
misclassiied as “lipomas” of the inguinal canal or spermatic cord. Circle, inferior epigastric artery.
cord lipomas can occur, but are rare. Nonsliding indirect inguinal
hernias are more diicult to diagnose sonographically than sliding
types because (1) they tend to be smaller; (2) they contain only
fat, which is almost isoechoic with surrounding tissues; and (3)
their nonreducibility minimizes motion of contents during
dynamic maneuvers. In the short axis, the sliding type of direct
inguinal hernia can be diagnosed at either the level of the internal
inguinal ring or the level of the inguinal canal. However, the
nonsliding type can be diagnosed only at the level of the inguinal
canal, where it is widest.
In some cases, it can be diicult to demonstrate the relationship
of the hernia neck to the inferior epigastric vessels. In such cases,
it is helpful to assess the relationship of the hernia sac to the
spermatic cord. In males, indirect inguinal hernias tend to lie