Diagnostic ultrasound ( PDFDrive )

204 PART II Abdominal and Pelvic Sonography
A
B
C
D
E
F
G
H
I
FIG. 6.45 Adenomyomatosis: Spectrum of Appearances. (A)-(C) Focal adenomyomatosis, the most common manifestation. (A) Small
focal area of thickening of the anterior fundal wall (arrow) with a bright echogenic focus with a distal comet-tail artifact. (B) Multiple bright foci
(arrow) with distal artifacts. (C) Highly echogenic focal thickening of the gallbladder wall (arrow). Increased echogenicity is unusual for a malignant
tumor that is more likely to appear hypoechoic. (D)-(F) Fundal adenomyomas. (D) Adenomyoma appears hypoechoic and masslike. (E) Caplike
area with multiple tiny, highly echogenic foci that suggest multiple crystals in the Rokitansky-Aschoff sinuses. (F) Multiple cystic spaces within the
adenomyoma. (G)-(I) Segmental adenomyomatosis. (G) and (H) Masslike areas obliterating the gallbladder lumen. Multiple cystic spaces suggest
the correct diagnosis. (I) Multiple echogenic foci suggest crystals in the Rokitansky-Aschoff sinuses.
polyps of the gallbladder constitute 5% to 10% of gallbladder
polyps and are multiple in one-half of the cases. 98 Inlammatory
polyps tend to occur in the background of gallstone disease and
chronic cholecystitis. 110 he sonographic appearance of these
lesions has not been systematically studied.
Malignancies
Primary gallbladder adenocarcinomas may appear as a polypoid
mass. Melanoma is reported to be the cause of 50% to 60%
of metastases to the gallbladder. hese appear as hyperechoic,
broad-based polypoid lesions, potentially multiple and usually
more than 10 mm in diameter. 111 But in our experience, the
most common metastases to the gallbladder are from signet ring
cell adenocarcinomas, particularly from gastric primaries.
However, these are not polypoid but rather difusely iniltrative
in nature, causing contraction of the gallbladder with a hyperemic
wall. In a series of 20 pathologically proven gallbladder
metastases, bowel adenocarcinomas accounted for 60% of