The Pearl Necklace Sign: An Imaging Sign of Adenomyomatosis of the Gallbladder at MR Cholangiopancreatography

Abstract

The pearl necklace sign, which indicates the presence of Rokitansky-Aschoff sinuses within the thickened gallbladder wall, was specifically detected at MRCP for adenomyomatosis of the gallbladder.

MRI of gallbladder cancer

“…The "pearl necklace" on heavily T2 images, which indicates the presence of Rokitansky-Aschoff sinuses within the thickened gallbladder wall, was reported to carry high accuracy for gallbladder adenomyomatosis (19). However, the true specificity of this sign has not been tested against GBCA.…”

Multidetector computed tomography diagnosis of adenomyomatosis of the gallbladder

“…The identification of the Rokitansky-Aschoff sinuses is the key factor in establishing a diagnosis of gallbladder adenomyomatosis. At present, magnetic resonance (MR) imaging is accepted as the most accurate modality in the delineation of Rokitansky-Aschoff sinuses (3)(4)(5). The ability of spiral computed tomography (CT) to depict these sinuses is limited due to insufficient spatial and contrast resolution (2,3 …”

“…The 'pearl necklace' or 'string of beads' sign is the hallmark of adenomyomatosis at MR imaging. It refers to small, rounded, high signal intensity foci within the thickened wall of the gallbladder on T2-weighted sequences, that correspond to bile filled Rokitansky-Aschoff sinuses (4,5). This sign is highly specific (92%) in diagnosing of gallbladder adenomyomatosis versus gallbladder cancer.…”

“…But the sign may be absent in cases of small sinuses (<3 mm) or sinuses filled with inspissated proteinaceous bile or small calculi. In such cases, its sensitivity is only 62% (5). Diffuse adenomyomatosis shows early mucosal enhancement on dynamic MR imaging, and the serosal aspect of the gallbladder can exhibit high signal intensity on T2-weighted images relative to their mucosal aspect (4,5).…”

Combined segmental and focal adenomyomatosis involving the body of the gallbladder

“…[1][2][3][4][5][6][7] Morphologically, adenomyomatosis is classified into three types: fundal (localized, focal), segmental, and diffuse. [1][2][3][4] Focal adenomyomatosis is the most common type, typically locating in the fundus of the gallbladder.…”