Back ground: The role of MRI is more rewarding as it is known that MRI details of soft tissue is superior than CT or any other imaging modalities and this quality is utilized in the evaluation of focal liver lesions, apart from the otheradvantages of MRI like, less risk of radiation, safe in renal disease, and being non invasive in the delineation of hepatic segmental anatomy and vascular anatomy and biliary anatomy and the sensitivity in detecting small lesions and the extent of lesions. Equivocal characteristics in an USS/CECT are better delineated by MRI. It also has a wide range of contrast enhancement than other technique and the diagnostic accuracy has increased by contrast enhanced MRI. The  tumor vascularity and its enhancement pattern is improved by Fast Breath Holding Sequences  using Gadolinium which is not possible on CT or USS.

Methods: A prospective study was conducted in the dept. of Radiodiagnosis, MCH, during the period of 2013 to 2016 on patients undergoing MR imaging of liver for characterisation of liver lesions.

Results: MRI has specific enhancement pattern for each focal liver lesions by which the focal lesions are characterized more accurately. The diagnostic accuracy of  the MRI characterization of focal lesions in our study were confirmed histopathologically or by FNA except  vascular lesions.

Conclusion: The value of contrast enhanced MRI in the evaluation of focal hepatic neoplasm is proved in this study. It is safe, lacks ionizing radiation and is highly sensitive and specific. Characterisation of focal liver lesion is very limited in ultrasound, which is the most commonly employed as a screening  modality, mainly for lesion detection in the majority of cases.

Keywords:  MRI, CT, focal liver lesions.

1. Schneck CD Embryology histology gross anatomy of the liver In Friedman A Dachman 1994 .Radiology of the liver
2. Michaels NA : Newer Anatomy of the liver and its variant blood supply and collateral circulation. Am J Surg. 112 :337 -347,1996
3. Sexton CC,Zeman RK:Correlation of Computed Tomography,Sonography and gross anatomy of the liver.AJR 141 :711 -718,1983
4. Ksales CJ,Patel S, Hopper KD; Imaging variants of the liver,pancreas and spleen.Crit Rev Diagn Imaging 35:485-543,1994
5. Lee Joseph KT., Sagel S.S. Stanley RJ. et al. Text book of Computed Body Tomography with MRI Correlation. Third Edition: Vol. 1: 1998: 701 - 707.
6. Rumack C.M., Wilson S.R. Charbonneau J.W., Textbook of Diagnostic Ultrasound.. 2^ndSt.Louis: CV Mosby,1998 pp95-96
7. Machell and RY. Calne: Solitary non-parasitic hepatic cyst presenting with jaundice. BJR51 :631-632,1978.
8. Dewburyk; Meire H; Cosgrove D. et al. Clinical Ultrasound A Comprehensive Text. Second Edition. Vol. 1, 2001 : 165- 231.
9. DuvnjakM, Supanc V, Virovic L, et al. Caroli’s disease. Acta Med Croatica2003; 57: 249–252.
10. MathieuD, Vilgrain V, Mahfouz A, et al. Benign liver tumors. Magn Reson Imaging Clin N Am1997; 5: 255–288.
11. ZanggerP, Grossholz M, Mentha G, et al. MRI findings in Caroli’s disease and intrahepatic pigmented calculi. Abdom Imaging1995; 20: 361–364.
12. MercadierM, Chigot JP, Clot JP, et al. Caroli’s disease. World J Surg1984; 8: 22–29.
13. AsselahT, Ernst O, Sergent G, et al. Caroli’s disease: a magnetic resonance cholangiopancreatography diagnosis. Am J Gastroenterol1998; 93: 109–110.
14. GovilS, Justus A, Korah I, et al. Choledochal cysts: evaluation with MR cholangiography. Abdom Imaging1998; 23: 616–619.
15. PavoneP, Laghi A, Catalano C, et al. Caroli’s disease: evaluation with MR cholangiopancreatography. AJR Am J Roentgenol1996; 166: 216–217.
16. Kadoya M,Matsui O, Nakanuma Y, et al; Ciliated hepatic foregut cysts:   1 1   Radiologic features. Radiology 175:475-477,1990
17. Shoenut JP, Semelka RC, Levi C, Greenberg H: Ciliated hepatic foregut cysts:US,CT and contrast enhanced  MR imaging.  Abdom imaging 19:150-152,1994
18. Balci NC, Tunaci A, Semelka RC, et al: Hepatic alveolar ecchinococcosis: MRI findings. Magn Reson Imaging 18:537-541,2000
19. WarshauerDM, Lee JK. Imaging manifestations of abdominal sarcoidosis. AJR Am J Roentgenol2004; 182: 15–28.
20. LehmuskallioE, Hannuksela M, Halme H. The liver in sarcoidosis. Acta Med Scand1977; 202: 289–293.
21. KlatskinG. Hepatic granulomata: problems in interpretation. Ann N Y Acad Sci1976; 278: 427–432.
22. KesslerA, Mitchell DG, Israel HL, et al. Hepatic and splenic sarcoidosis: ultrasound and MR imaging. Abdom Imaging1993; 18: 159–163.
23. WarshauerDM, Molina PL, Hamman SM, et al. Nodular sarcoidosis of the liver and spleen: analysis of 32 cases. Radiology1995; 195: 757–762.
24. BalciNC, Sirvanci M. MR imaging of infective liver lesions. Magn Reson Imaging Clin N Am2002; 10: 121–135.
25. RallsPW. Inflammatory disease of the liver. Clin Liver Dis2002; 6: 203–225.
26. RallsPW. Focal inflammatory disease of the liver. Radiol Clin North Am1998; 36: 377–389.
27. BakerRD. Histoplasmosis in routine autopsies. Am J Clin Pathol1964; 41: 457–470.
28. AllaireGS, Rabin L, Ishak KG, Sesterhenn IA. Bile duct adenoma: a study of 152 cases. Am J Surg Pathol1988; 12:708–715.
29. Semelka RC, Hussain SM, Marcos HB, Woosley JT. Biliaryhamartomas: solitary an multiple lesions shown on current MR techniques including gadolinium enhancement. J. Magn. Reson. Imaging 1999; 10: 196–201 417,1993.
30. Li KC,Glazer GM,Quinr LE, et al: Distinction of hepatic cavernous hemangioma from hepatic metastasis with MR imaging. Radiology 169:409-415,1998
31. Lombardo DM,Baker ME, Spritzer CE,et al:Hepatic hemangiomas vs metastasis: MR differentiation at 1.5 T.Am J Roentgenol155:55-59,1990.
32. Danet IM, Samelka RC,Braga L,et al: Giant hemangioma of the liver: MR imaging characteristics in 24 patients. Magn Reson Imaging 21:95-101,2003.
33. Selbi DM,Stoker JT,Waclawiw MA, et al: Infantile hemangioendothelioma of liver. Hepatology 20(I Pt 1): 39-45,1994.
34. Chen CC, Kong MS, Yang CP, Hung IJ: Hepatic hemangioendothelioma in children: analysis of thirteen cases.Acta Paediatr Taiwan 44:8-13, 2003.
35. Mortele KJ, Vanzieleghem B, Mortele B,et al: Solitary hepatic infantile hemangioendothelioma : dyanamic gadolinium enhanced MR imaging findings. Eur Radiol 12 862-865,2002.
36. Schneider G, Grazioli L, Saini S: Imaging of benign focal liver lesions. In Schneider G, Grazioli L, Saini S(eds): MRI of the Liver. New York: Springer, 2003,pp 144-145.
37. Shortell CK, Schwartz SI. Hepatic adenoma and focalnodular hyperplasia. Surg. Gynecol. Obstet. 1991; 173:426–31.
38. Mortelé KJ, Praet M, Vlierberghe HV, Kunnen M, RosPR. CT and MR imaging findings in focal nodular hyperplasiaof the liver: radiologic- Pathologic correlation. AJR2000; 175: 687–92.
39. Robbins: Pathologic Basis of Disease, V Edition
40. Shortell CK, Schwartz SI. Hepatic adenoma and focalnodular hyperplasia. Surg. Gynecol. Obstet. 1991; 173:426–31.
41. Paulson EK, McClellan JS, Washington K, Spritzer CE,Meyers WC, Baker ME. Hepatic adenoma: MR characteristicsand correlation with pathologic findings. Am. J.Roentgenol. 1994; 163: 113–16.
42. Martin DR, Semelka RC. Imaging of benign and malignantfocal liver lesions. MRI Clin. N. Am. 2001; 9: 785–802.
43. Nonomura A, Mizukami Y Cadoya M: Angimyolipoma of liver: a collective review.J Gastro enterol 29: 95-105,1994.
44. Worawattanakul S, Kelekis NL,Semelka RC, Woosley JT:Hepatic angiomyolipoma with minimal fat content ; MR demonstration. Magn Reson Imaging 14:687-689,1996.
45. HortonKM, Bluemke DA, Hruban RH, et al. CT and MR imaging of benign hepatic and biliary tumors. RadioGraphics1999; 19: 431–451.
46. Wong Y,Chen F, Tai KS, et al: Imaging features of focal intrahepatic extramedullary haematopoeisis. Br J Radiol72:906-910,1999.
47. Warshauer DM, Schiebler ML; Intrah-epatic extramedullary haematopoeisis; MR, CT, and sonographic appearance. J Compur Assist Tomogr 15:683-685,1991.
48. MorteléKJ, Ros PR. Cystic focal liver lesions in the adult: differential CT and MR imaging features. RadioGraphics2001; 21: 895–910.
49. Abraham H. Dachman et al : Nodular Regenerative Hyperplasia of the Liver: AJR V01.l48:717-722, 1987
50. Dehner LP, Ewing SL, Summer HW: Infantile mesenchymal hamartoma of the liver. Histologic and ultrastructural observations. Arch Pathol1:245-267,1983.
51. Stocker JT, Ishak KG : Mesenchymal hamartoma of the liver: report of 30 cases and review of the literature. Paediatr Pathol 1:245-267, 1983.
52. Molina EG, Schiff ER: Benign solid lesions of the liver. In SCHIFF er,Sorell MF, Maddrey WC (eds): Diseases of the Liver (8^th ed).  Philadelphia: Lippincott Williams, 1999, pp 1245-1268.
53. Ros PR, Goodman ZD, Ishak KG, et al: Mesenchymal hamartoma of the liver: radiologic-pathologic correlation. Radiology 158:619-624, 1986.
54. O’Neil J, Ros PR: Knowing hepatic pathology aids MRI of liver tumors. Diagn Imaging 19:58-67, 1989
55. Danet IM, Semelka RC, Leonardou P et al. Spectrum ofMRI appearances of untreated metastases of the liver. Am.J. Roentgenol. 2003; 181: 809–17.
56. Hamm B, Thoeni RF, Gould RG et al. Focal liver lesions:characterization with nonenhanced and dynamic contrast-aterial-enhanced MR imaging. Radiology 1994; 190:417–23.

Preetha S

Associate Professor, Dept of General Surgery, Govt Medical College, Thiruvananthapuram,

Kerala, India 695011

Email: arulakam69@gmailcom