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Citation Information : Journal of Ultrasonography. Volume 15, Issue 62, Pages 318-325, DOI: https://doi.org/10.15557/JoU.2015.0028
License : (CC BY-NC-ND 3.0)
Received Date : 30-August-2014 / Accepted: 14-April-2015 / Published Online: 13-September-2016
Unaltered fat is a permanent component of the abdominal cavity, even in slim individuals. Visceral adiposity is one of the important factors contributing to diabetes, cardiovascular diseases and certain neoplasms. Moreover, the adipose tissue is an important endocrine and immune organ of complex function both when normal and pathological. Its role in plastic surgery, reconstruction and transplantology is a separate issue. The adipose tissue has recently drawn the attention of research institutes owing to being a rich source of stem cells. This review, however, does not include these issues. The identifi cation of fat is relatively easy using computed tomography and magnetic resonance imaging. It can be more diffi cult in an ultrasound examination for several reasons. The aim of this paper is to present various problems associated with US imaging of unaltered intra-abdominal fat located beyond organs. Based on the literature and experience, it has been demonstrated that the adipose tissue in the abdominal cavity has variable echogenicity, which primarily depends on the amount of extracellular fl uid and the number of connective tissue septa, i.e. elements that potentiate the number of areas that refl ect and scatter ultrasonic waves. The normal adipose tissue presents itself on a broad gray scale: from a hyperechoic area, through numerous structures of lower refl ection intensity, to nearly anechoic regions mimicking the presence of pathological fl uid collections. The features that facilitate proper identifi cation of this tissue are: sharp margins, homogeneous structure, high compressibility under transducer pressure, no signs of infi ltration of the surrounding
structures and no signs of vascularization when examined with the color and power Doppler. The accumulation of fat tissue in the abdominal cavity can be generalized,
regional or focal. The identifi cation of the adipose tissue in the abdominal cavity using ultrasonography is not always easy. When in doubt, the diagnostic process should be extended to include computed tomography or magnetic resonance imaging, or sometimes biopsy (preferably the core-needle one).
1. Schmidt G: Differential diagnosis in ultrasound imaging. A teaching atlas. Georg Thieme Verlag, Stuttgart 2006.
2. Rumack CM, Wilson SR, Charboneau JW, Levine D: Diagnostic ultrasound. Vol. 1, Elsevier Mosby, Philadelphia 2011.
3. Walas MK, Skoczylas K, Gierbliński I: Standards of the Polish Ultrasound Society – update. The liver, gallbladder and bile ducts examinations. J Ultrason 2012; 12: 428–445.
4. Ćwik G, Gierbliński IW: Errors and mistakes in the ultrasound diagnosis of the pancreas. J Ultrason 2013; 13: 178–191.
5. Jakubowski W, Dobruch-Sobczak K, Migda B: Errors and mistakes in breast ultrasound diagnostics. J Ultrason 2012; 12: 286–298.
6. Dobruch-Sobczak K: The differentiation of the character of solid lesions in the breast in the compression sonoelastrography. Part I: The diagnostic value of the ultrasound B-mode imaging in the differentiation diagnostics of solid, focal lesions in the breast in relation to the pathomorphological vertifi cation. J Ultrason 2012; 12: 402–419.
7. Sudoł-Szopińska I, Konty E, Zaniewicz-Kaniewska K, Prohorec-Sobieszek M, Saied F, Maśliński W: Role of infl ammatory factors and adipose tissue in pathogenesis of rheumatoid arthritis and osteoarthritis. Part I: Rheumatoid adipose tissue. J Ultrason 2013; 13: 192–201.
8. Błogowski WM: Analiza wybranych aspektów środowiska ludzkiej tkanki tłuszczowej. Praca habilitacyjna. Szczecin 2013.
9. Smith CS, Teruya-Feldstein J, Caravelli JF, Yeung HW: False-positive fi ndings on 18F-FDG PET/CT: differentiation of hibernoma and malignant fatty tumor on the basis of fl uctuating standardized uptake values. AJR Am J Roentgenol 2008; 190: 1091–1096.
10. Hu HH, Perkins TG, Chia JM, Gilsanz V: Characterization of human brown adipose tissue by chemical-shift water-fat MRI. AJR Am J Roentgenol 2013; 200: 177–183.
11. Sawicki W: Histologia. Wydawnictwo Medyczne PZW, Warszawa 2008.
12. Craig WD, Fanburg-Smith C, Henry LR, Guerrero R, Barton JH: Fatcontaining lesions of the retroperitoneum: radiologic-pathologic correlation. Radiographics 2009; 29: 261–290.
13. Kunin M: Bridging septa of the perinephric space: anatomic, pathologic and diagnostic considerations. Radiology 1986; 158: 361–365.
14. Sheth S, Fishman EK, Buck JL, Hamper UM, Sanders RC: The variable sonographic appearances of ovarian teratomas: correlation with CT. AJR Am J Roentgenol 1988; 151: 331–334.
15. Spencer GM, Rubens DJ, Roach DJ: Hypoechoic fat: a sonographic pitfall. AJR Am J Roentgenol 1995; 164: 1277–1280.
16. Coulier B: 64-row MDCT review of anatomic features an variations of the normal greater omentum. Surg Radiol Anat 2009; 31: 489–500.
17. Smereczyński A, Starzyńska T, Kołaczyk K, Bojko S, Gałdyńska M, Bernatowicz E et al.: Intra-abdominal adhesions in ultrasound. Part I: The visceroperitoneal borderline, anatomy and the method of examination. J Ultrason 2012; 12: 472–478.
18. Vijayaraghavan SB: Fat pad vs. anterior subphrenic abscess: a new realtime sign. J Clin Ultrasound 1989; 17: 653–655.
19. Fremault A, Heylen C, Delugeau V, Landen S: Mesenteric liposarcoma or lipodystrophy: an elusive diagnosis. JBR-BTR 2001; 84: 102–104.
20. Premkumar A, Chow C, Bhandarkar P, Wright V, Koshy N, Taylor S et al.: Lipoatrophic-lipodystrophic syndromes: the spectrum of fi ndings on MR imaging. AJR Am J Roentgenol 2002; 178: 311–318.
21. Smereczyński A, Szopiński T, Gołąbek T, Ostasz O, Bojko S: Sonography of tumors and tumor-like lesions that mimic carcinoma of the urinary bladder. J Ultrason 2014; 14: 36–48.
22. Kani KK, Moshiri M, Bhargava P, Kolokythas O: Extrahepatic, nonneoplastic, fat-containing lesions of the abdominopelvic cavity: spectrum of lesions, signifi cance, and typical appearance on multidetector computed tomography. Curr Prob Diagn Radiol 2012; 41: 56–72.