Adenomyomatosis Imaging
No Results
No Results
processing….
Adenomyomatosis is a benign condition characterized by hyperplastic changes of unknown etiology involving the gallbladder wall and causing overgrowth of the mucosa, thickening of the muscular wall, and formation of intramural diverticula or sinus tracts termed Rokitansky-Aschoff sinuses. Adenomyomatosis is a common tumorlike lesion of the gallbladder with no malignant potential and may involve the gallbladder in a focal, segmental, or diffuse form. The focal type is the most common and usually involves the gallbladder fundus. Differentiating between adenomyomatosis and cholesterolosis is difficult at times. Hyperplastic cholecystosis is the term used to describe cholesterolosis and adenomyomatosis.
The etiology of cholesterolosis is also unknown. Cholesterolosis is a local phenomenon unrelated to atherosclerosis. Triglycerides and cholesterol esters are deposited in the lamina propria of the gallbladder wall. Grossly, the lipid deposits are visible, lending the gallbladder wall a strawberry-like appearance—hence, the term strawberry gallbladder. The deposits vary in size and can be as large as 1 cm.
Ultrasonography (US) is the preferred radiologic examination. Oral cholecystogram can be used to diagnose adenomyomatosis; however, use of ultrasonography (US) and magnetic resonance imaging (MRI) is preferred. MRI, computed tomography (CT) scanning, and positron emission tomography (PET) can be used as problem-solving modalities, especially to differentiate hyperplastic cholecystosis from gallbladder carcinoma. [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
Occasionally, US cannot differentiate between the segmental type of adenomyomatosis and gallbladder carcinoma.
The imaging characteristics of adenomyomatosis are demonstrated in the images below. [13, 1, 14]
If Rokitansky-Aschoff sinuses are patent, oral cholecystogram demonstrates the characteristic appearance of sinuses filled with contrast. (See the image below.)
In patients with cholesterolosis, an oral cholecystogram demonstrates the larger polypoid cholesterol deposits as fixed lucencies in the opacified lumen. The deposits are distinguished from gallbladder stones by a failure to move with compression and positional change. Ultrasonography shows the lesions as nonshadowing, nonmobile intraluminal echoes.
CT scans of adenomyomatosis reveal a thickened gallbladder wall with the rosary sign. The rosary sign is formed by the enhanced proliferative mucosal epithelium, with the intramural diverticula surrounded by the unenhanced hypertrophied muscle coat of the gallbladder. [1, 9, 15, 16]
Findings on CT scan usually are confirmed further by other imaging modalities. CT is useful in excluding gallbladder carcinoma.
Ching et al studied the accuracy of CT in differentiating adenomyomatosis from gallbladder cancer in a retrospective study of 36 patients with pathologically proven adenomyomatosis or gallbladder cancer who had undergone preoperative abdominal CT. The authors determined from study findings that CT is limited in the detection and differentiation of adenomyomatosis and gallbladder cancer, but the diagnosis of adenomyomatosis can be made with reasonable accuracy when thickening of the gallbladder wall is seen to contain small cystic-appearing spaces. [1]
MRI can be used in cases that are difficult to diagnose, being well able to differentiate adenomyomatosis from cholesterolosis. [5, 9, 17, 18] Gallbladder wall thickening with multiple intramural cystic components from Rokitansky-Aschoff sinuses can be visualized readily using MRI and is considered diagnostic of adenomyomatosis.
On T2-weighted MRI imaging, the pearl necklace sign refers to multiple high-intensity cavities seen in the gallbladder wall. This pathognomonic sign carries 92–98% specificity for adenomyomatosis. [5] However, it is only present in 70% of patients, and it becomes difficult to visualize when Rokitansky-Aschoff sinuses are smaller than 3 mm or in sinuses filled with proteinaceous fluid or small stones. Magnetic resonance cholangiopancreatography (MRCP) is able to identify smaller Rokitansky-Aschoff sinuses, and the combined use of MRI and MRCP has been proposed to differentiate adenomyomatosis from gallbladder cancer in the absence of the pearl necklace sign. [19]
Diffuse-type adenomyomatosis typically shows early mucosal enhancement and subsequent serosal enhancement. Localized adenomyomatosis exhibits homogeneous enhancement, showing smooth continuity with the surrounding gallbladder epithelium.
Differentiation of echogenic intramural foci from abnormal enhancement requires a multiphasic MRI protocol with intravenous contrast material. Diffusion-weighted imaging has been found to be useful in differentiating gallbladder adenomyomatosis from gallbladder carcinoma and significantly improves the diagnostic accuracy. [20]
Intramural cystic formation (anechoic diverticula) with echogenic foci and/or reverberation artifacts together with full or partial thickening of the gallbladder wall are considered to be the diagnostic findings on US examination. Reverberation artifact from cholesterol crystals is V-shaped and shorter in length than artifact from air. Sometimes, the calcium present within the sinuses may give rise to twinkle artifact.
On US, diffuse or segmental gallbladder wall thickening is evident. Intramural diverticula may be seen. Diverticula containing bile are anechoic, and those containing sludge or stone are hyperechoic, with or without shadowing or reverberation artifacts.
If intramural diverticula are not identified, differentiating adenomyomatosis from other causes of gallbladder wall thickening, such as inflammation or carcinoma, is difficult. [9, 10, 11]
(See the images below.)
Segmental and focal adenomyomatosis may be difficult to differentiate from gallbladder carcinoma if characteristic features are not present.
Contrast-enhanced ultrasound (CEUS) has been used for the diagnosis of adenomyomatosis and is considered a valuable complement to conventional US. CEUS may be useful for differentiating malignant tumors from sludge and can also differentiate cystic structures from parenchymal structures. Visualization of Rokitansky-Aschoff sinuses is increased compared to gray scale US. Two “hyper-echoic lines” around the lesion with the small nonenhancement spaces in the arterial phase of CEUS are the characteristic findings of adenomyomatosis. [21]
In a study of 105 gallbladder lesions, CEUS sensitivity was higher than that of conventional ultrasound(94.1% vs 82.4%), as well as specificity (95.5% vs 89.8%), positive predictive value (80.0% vs 60.9%), negative predictive value (98.8% vs 96.3%) and accuracy (95.2% vs 88.6%). [22]
Small polypoid lesions of strawberry gallbladder can be differentiated successfully from gallbladder carcinoma using PET scanning with 18-fluorodeoxyglucose (FDG). PET reveals a focus of FDG uptake at the site of gallbladder carcinoma. No focal uptake is noted in cholesterol polyps. [23] However, few reports, consisting mostly of case reports, have examined the utility of PET scan alone or in combination with 18F-labeled deoxyglucose (FDG-PET) for adenomyomatosis imaging, and no evidence exists to support the routine use of FDG-PET scan. [19]
Ching BH, Yeh BM, Westphalen AC, Joe BN, Qayyum A, Coakley FV. CT differentiation of adenomyomatosis and gallbladder cancer. AJR Am J Roentgenol. 2007 Jul. 189(1):62-6. [Medline].
Ash-Miles J, Roach H, Virjee J, Callaway M. More than just stones: a pictorial review of common and less common gallbladder pathologies. Curr Probl Diagn Radiol. 2008 Sep-Oct. 37(5):189-202. [Medline].
Stunell H, Buckley O, Geoghegan T, O’Brien J, Ward E, Torreggiani W. Imaging of adenomyomatosis of the gall bladder. J Med Imaging Radiat Oncol. 2008 Apr. 52(2):109-17. [Medline].
Poonam Y, Ashu S, Rohini G. Clinics in diagnostic imaging (121). Gallbladder adenomyomatosis. Singapore Med J. 2008 Mar. 49(3):262-4; quiz 265. [Medline].
Catalano OA, Sahani DV, Kalva SP, Cushing MS, Hahn PF, Brown JJ, et al. MR imaging of the gallbladder: a pictorial essay. Radiographics. 2008 Jan-Feb. 28(1):135-55; quiz 324. [Medline].
Joo I, Lee JY, Kim JH, Kim SJ, Kim MA, Han JK, et al. Differentiation of adenomyomatosis of the gallbladder from early-stage, wall-thickening-type gallbladder cancer using high-resolution ultrasound. Eur Radiol. 2013 Mar. 23(3):730-8. [Medline].
Ogawa T, Horaguchi J, Fujita N, Noda Y, Kobayashi G, Ito K, et al. High b-value diffusion-weighted magnetic resonance imaging for gallbladder lesions: differentiation between benignity and malignancy. J Gastroenterol. 2012 Dec. 47(12):1352-60. [Medline].
Tsuji S, Sofuni A, Moriyasu F, Itokawa F, Ishii K, Kurihara T, et al. Contrast-enhanced ultrasonography in the diagnosis of gallbladder disease. Hepatogastroenterology. 2012 Mar-Apr. 59(114):336-40. [Medline].
Bang SH, Lee JY, Woo H, Joo I, Lee ES, Han JK, et al. Differentiating between adenomyomatosis and gallbladder cancer: revisiting a comparative study of high-resolution ultrasound, multidetector CT, and MR imaging. Korean J Radiol. 2014 Mar-Apr. 15 (2):226-34. [Medline].
Joo I, Lee JY, Kim JH, Kim SJ, Kim MA, Han JK, et al. Differentiation of adenomyomatosis of the gallbladder from early-stage, wall-thickening-type gallbladder cancer using high-resolution ultrasound. Eur Radiol. 2013 Mar. 23 (3):730-8. [Medline].
Imazu H, Mori N, Kanazawa K, Chiba M, Toyoizumi H, Torisu Y, et al. Contrast-enhanced harmonic endoscopic ultrasonography in the differential diagnosis of gallbladder wall thickening. Dig Dis Sci. 2014 Aug. 59 (8):1909-16. [Medline].
Tang S, Huang L, Wang Y, Wang Y. Contrast-enhanced ultrasonography diagnosis of fundal localized type of gallbladder adenomyomatosis. BMC Gastroenterol. 2015 Aug 5. 15:99. [Medline].
Boscak AR, Al-Hawary M, Ramsburgh SR. Best cases from AFIP:Adenomyomatosis of the gallbladder. Radiographics. 2006. 3:941-946.
Owen CC, Bilhartz LE. Gallbladder polyps, cholesterolosis, adenomyomatosis, and acute acalculous cholecystitis. Semin Gastrointest Dis. 2003 Oct. 14(4):178-88. [Medline].
Chao C, Hsiao HC, Wu CS, Wang KC. Computed tomographic finding in adenomyomatosis of the gallbladder. J Formos Med Assoc. 1992 Apr. 91(4):467-9. [Medline].
Kim BS, Oh JY, Nam KJ, Cho JH, Kwon HJ, Yoon SK, et al. Focal thickening at the fundus of the gallbladder: computed tomography differentiation of fundal type adenomyomatosis and localized chronic cholecystitis. Gut Liver. 2014 Mar. 8 (2):219-23. [Medline].
Kim MJ, Oh YT, Park YN, et al. Gallbladder adenomyomatosis: findings on MRI. Abdom Imaging. 1999 Jul-Aug. 24(4):410-3. [Medline].
Yoshimitsu K, Honda H, Jimi M, et al. MR diagnosis of adenomyomatosis of the gallbladder and differentiation from gallbladder carcinoma: importance of showing Rokitansky-Aschoff sinuses. AJR Am J Roentgenol. 1999 Jun. 172(6):1535-40. [Medline].
Hammad AY, Miura JT, Turaga KK, Johnston FM, Hohenwalter MD, Gamblin TC. A literature review of radiological findings to guide the diagnosis of gallbladder adenomyomatosis. HPB (Oxford). 2016 Feb. 18 (2):129-135. [Medline]. [Full Text].
Tomizawa M, Shinozaki F, Fugo K, Sunaoshi T, Sugiyama E, Kano D, et al. Negative signals for adenomyomatosis of the gallbladder upon diffusion-weighted whole body imaging with background body signal suppression/T2-weighted image fusion analysis. Exp Ther Med. 2016 May. 11 (5):1777-1780. [Medline]. [Full Text].
Tang S, Huang L, Wang Y, Wang Y. Contrast-enhanced ultrasonography diagnosis of fundal localized type of gallbladder adenomyomatosis. BMC Gastroenterol. 2015 Aug 5. 15:99. [Medline]. [Full Text].
Zhang HP, Bai M, Gu JY, He YQ, Qiao XH, Du LF. Value of contrast-enhanced ultrasound in the differential diagnosis of gallbladder lesion. World J Gastroenterol. 2018 Feb 14. 24 (6):744-751. [Medline]. [Full Text].
Koh T, Taniguchi H, Kunishima S, Yamagishi H. Possibility of Differential Diagnosis of Small Polypoid Lesions in the Gallbladder Using FDG-PET. Clin Positron Imaging. 2000 Sep. 3(5):213-218. [Medline].
Vikram S Dogra, MD Professor of Diagnostic Radiology, Urology, and Biomedical Engineering, University of Rochester School of Medicine; Director, Division of Ultrasound, Associate Chair of Education and Research, Department of Imaging Sciences, University of Rochester Medical Center
Vikram S Dogra, MD is a member of the following medical societies: American College of Radiology, Association of Program Directors in Radiology, Society of Radiologists in Ultrasound, American Institute of Ultrasound in Medicine, American Roentgen Ray Society, Radiological Society of North America, Society of Abdominal Radiology
Disclosure: Nothing to disclose.
Bernard D Coombs, MB, ChB, PhD Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand
Disclosure: Nothing to disclose.
Arnold C Friedman, MD, FACR Professor, Department of Radiology, University of Florida Health Science Center; Chief, Department of Radiology, Shands-Jacksonville Hospital
Arnold C Friedman, MD, FACR is a member of the following medical societies: American College of Radiology, American Institute of Ultrasound in Medicine, American Roentgen Ray Society, Association of University Radiologists, Radiological Society of North America
Disclosure: Nothing to disclose.
John Karani, MBBS, FRCR Clinical Director of Radiology and Consultant Radiologist, Department of Radiology, King’s College Hospital, UK
John Karani, MBBS, FRCR is a member of the following medical societies: British Institute of Radiology, Radiological Society of North America, Royal College of Radiologists, Cardiovascular and Interventional Radiological Society of Europe, European Society of Radiology, European Society of Gastrointestinal and Abdominal Radiology, British Society of Interventional Radiology
Disclosure: Nothing to disclose.
Eric P Weinberg, MD Associate Professor, Department of Radiology, University of Rochester Medical Center, Strong Memorial Hospital
Eric P Weinberg, MD is a member of the following medical societies: American College of Radiology, American Roentgen Ray Society, Radiological Society of North America
Disclosure: Nothing to disclose.
Adenomyomatosis Imaging
Research & References of Adenomyomatosis Imaging |A&C Accounting And Tax Services
Source
0 Comments