 Hello everyone, myself, Dr. Prathik from Department of Radiative Diagnosis, Mysore Medical College and Research Institute. I will be presenting a paper on the role of triple-phase MDCT in the characterization of focal liver lesions with cytopathological correlation. Introduction, focal liver lesion can be defined as an indigestion in the liver other than the normal parenchyma with or without causing structural and functional abnormality of the hepatography system. Prevalence of various liver lesions has markedly increased and presents a relatively common clinical dilemma, particularly with the increasing use of various imaging moderates in the diagnosis of abdominal symptoms. It is very important to correctly differentiate between benign or malignant lesions as there are many do not touch benign lesions like hematoma, simple cysts, appendages, etc. Most of the primary and metastatic liver lesions deceive their blood supply from the hepatic artery, thus reversing the normal proportion of hepatic blood supply, which is mainly by the portal vein to the hepatic artery. Direct characterization of liver masses by cross-sectional imaging is particularly dependent on an understanding of the unique phasic vascular profession of the liver and the characteristic behavior of different lesions during multifasic contrast imaging i.e. RTL portal equilibrium and delayed phases. Ames and objectives of the study were to evaluate the usefulness of triphasic MDCT in the detection and characterization of focal liver lesions and provide information for further management and to assess the sensitivity and specificity of the triphasic computed tomography in accurate and reliable determination of the nature of liver lesions in correlation with FNSE or histopathology. Coming to materials and methods, the study was a descriptive study and was conducted for a period of one year. The source of data were patients referred to our department with focal liver lesions who underwent triphasic MDCT. The sample size was 81. The calculation was based on an estimated prevalence of focal liver lesions amenable to triple phase studies as per the hospital prevalence at 5% level of significance and absolute precision of 5% using confidence interval approach for proportion. Patients of all age groups and of either gender who presented with clinical suspicion of liver disease, patients with suspected focal liver lesions by other imaging modalities were included in the study. Patients with past history of hypersensitivity reaction to iodinated contrast agents, all pregnant females and patients with t-range renal function test and coagulation profile were accelerated from the study. All the CT examinations were acquired by Siemens somatom definition as 128 slide helical CT scanner in arterial, portal venous and equilibrium and delayed phases. All patients with mass regions of liver except typical hemangiomas were subjected to FNSE or biopsy for pathological analysis. Results In our study, majority of the patients were in the age range of 41 to 60 years which concentrated 45.7% of the patient. The mean age group of the patient was 5th decade. There was a male pre-pregnancy scene where in 56.8% patients were males and 43.2% patients were females. 42 patients were diagnosed to have malignant focal liver lesions and 33 patients had benign focal liver lesions. Overall, most common malignant focal lesion was metastasis accounting for 40% of the cases. However, most common primary malignant lesion was HCC accounting for 13.3% of the cases. Amongst females, metastasis was the most common lesion seen in 12 patients, followed by hemangioma seen in 9 patients, hepatosolular carcinoma and cholangiocarcinoma. Then two cases each of hepatic adenoma and focal nodular hyperplasia and one case of dysplastic nodule. Amongst males, metastasis seen in 18 patients and HCC seen in 13 patients were the most common lesions followed by hemangioma and cholangiocarcinoma seen in 5 patients and two cases of regenerative nodules and one case of cisterin of carcinoma was C. 17 patients had the history of smoking, 24 patients had a history of alcoholism, four patients had zero possibility for hepatitis B and one patient had zero possibility for hepatitis C. Most of the patients had no previous known risk factors. One plane scan, 9 lesions showed calcification and 8 lesions showed fat components. 15 lesions showed IHPRD and 12 cases showed capsular retraction on plane scans, most of which were cholangiocarcinomas. Out of the 27 hypovascular lesions, 2 cases were benign and 25 cases were malignant and out of the 54 hypervascular lesions, 18 cases were benign and 36 cases were malignant. On plane study, most of the benign lesions that is 15 cases were and malignant 45 cases were hypodense compared to normal surrounding hepatic parenchyma. On arterial phase, 90 percent of the benign lesions showed enhancement and among the benign lesions, 60 percent of the lesions showed peripheral puddles of enhancement on arterial phase, 15 percent cases showed heterogeneous enhancement, 15 percent cases appeared hypodense and 10 percent remained isodense on arterial phase. Among malignant lesions, 41 percent of the lesions appeared hypodense, 32.8 percent showed heterogeneous enhancement, 11.5 percent showed peripheral lint of enhancement and 9.8 percent cases appeared hypodense and 4.9 percent cases remained isodense to live. On portal venous phase, most of the benign lesions showed progressive centripetal feeling which was seen only in benign lesions and 30 percent of the lesions showed heterogeneous enhancement and the remaining 25 percent lesions remained hypodense. Majority of the malignant lesions on the other hand showed heterogeneous or peripheral lint of enhancement. This heterogeneity was due to the presence of a non-enhancing area within which a shade of necrosis. On equilibrium phase imaging, majority of the benign lesions showed progressive centripetal enhancement. Among the malignant lesions, most of the cases which showed heterogeneous enhancement on arterial and portal venous phases became hypodense or isodense compared to the surrounding paracama owing to the rapid washout of the contrast. 4.9 percent cases showed progressive centripetal enhancement. A case of hemangioma showed a well-defined hypodense lesion in the left globe of liver. The lesion showed peripheral pettles of nodular discontinuous enhancement in arterial and portal venous phase with progressive centripetal feeling in delayed phase. Case of focal nodular hyperplasia showed a well-defined isodense lesion with central hypodense area in the left globe of liver which showed homogenous enhancement in arterial and portal venous phases with central non-enhancing areas. The lesion turned isodense to liver paracama in equilibrium phase and there was delayed enhancement of the central hypodense area with a shade of scar. Case of hepatic oedema showed a well-defined hyperdense lesion in the right globe of liver which showed intense enhancement in arterial and portal venous phase and the lesion turned isodense on equilibrium and delayed phase. There was no evidence of central scar. Case of Wilson's disease with regenerative nodules showed multiple lesions in the liver which showed enhancement only in the portal venous phase. The lesion remained isodense to the liver in all the rest all phases and were unidentifiable in other phases. Case of chronic liver disease with dysplastic nodule the liver showed surface nodularity with cross asitis. Isodense lesion noted in the left globe of liver was seen which showed enhancement in arterial and portal venous phases. The lesion did not show wash out in equilibrium and delayed phases and remained isodense to the liver. In the case of HCC the liver showed surface micro nodularity and a fairly well-defined isodense lesion with internal calcification in the right globe of liver was seen which showed heterogeneous enhancement on arterial and portal venous phase with wash out and enhancement of the capsule on delayed phases. In a case of carcinoma stomach with liver melt the liver showed multiple well-defined isodense lesions randomly distributed in both lobes. The lesions show minimal enhancement in arterial phase the peripheral range of enhancement with few central non enhancing areas in portal venous phase and wash out in delayed phase. Enhancing wall thickening was noted involving the lesser curvature of stomach with pericastric lymph nodes. In a case of mass forming intra hepatic colonio carcinoma an ill-defined high-prone lesion noted involving both lobes of liver was seen which showed minimal peripheral enhancement in arterial phase progressive centripetal heterogeneous enhancement with multiple central non-enhancing areas in portal and equilibrium phases with a set of necrosis. The lesion was seen and casing both branch of the portal ven rather than infiltrating them. Mild inter hepatic bilirary radical dilatation with capsular retraction was seen. Progressive persistent central enhancement was noted in the delayed phases. Coming to discussion a total of 81 patients were included in the study 20 lesions were benign and 61 lesions were malignant. Most common benign lesion was hemangioma. The most common malignant lesion was metastasis seen in 30 patients followed by hepatitis cellular carcinoma seen in 18 patients. In a study conducted by Chandrasekhar Prakash Ahirvar et al. there were 40 benign and 60 malignant lesions. This correlated with our study. In our study most of the patients were in the age range of 41 to 60 years followed by more than 60 years and there was a male preponderance of cases. In a similar study conducted by Sapshitomar et al. maximum number of patients were aged between 61 and 80 years followed by those aged between 41 and 60 years and male preponderance was noted. This correlated with our study. In our study hemangioma was the most common benign lesion accounting for 14 cases. On arterial phase imaging 12 cases showed periferous puddles of enhancement on arterial phase with progressive centripetal filling on portal venus and equilibrium phases. These findings were in agreement with those of Bartolota et al. There were two cases of FNH in our study and there was heterogeneous enhancement seen in arterial and portal venus phase which became isodens on equilibrium phase. The scar showed enhancement on equilibrium and delirious phase imaging. Similar findings were described by studies conducted by Blasher, Federer, Ferris JV and Anderson SW study. Two patients with cirrhosis showed regenerative nodules. The nodules remained isodens in all phases except in portal venus phase in which mild enhancement was noted. Three cases of dysplastic nodules were noted. None of the lesions showed washout on equilibrium phase imaging. These findings are in correlation with the study conducted by J. H. Lim et al. Out of 18 hepatocellular carcinoma cases, all the cases had cirrhotic liver. On post-contrast imaging 17% showed typical pattern of heterogeneous enhancement in late arterial phase and similar findings were described in a study done by Andrea Lackey et al. Rapid washout of the contrast in portal venus phase was noted in 12 cases and 17% of the cases showed washout in equilibrium phase. Similar findings were obtained in a study by Ferlan et al. There are 9 cases of colonio carcinoma in our study. 7 cases were associated with inter hepatic biliary radical dilatation. 6 cases were peripherally located and showed capsular retraction. Take him et al. in the study of 34 cases of colonio carcinoma showed that 76% cases were associated with inter hepatic biliary radical dilatation. 88.9% cases showed no enhancement on arterial phase with progressive enhancement in portal venus and equilibrium phases. There was progressive centripetal enhancement on dilate sequence. Similar findings as described by Nisha et al. We had 30 cases of metastasis which was the most common lesion in our study. This finding correlated well with the study done by Gowel et al who had 42.1% metastatic lesions in their study. Colorectal carcinoma and carcinoma of stomach were the most common site of primary neoplasms in our study. Conclusion triple-phase CT proved to be a valuable tool in the diagnosis of focal liver lesion. Studying the pattern of enhancement in arterial, portal venus and equilibrium phases helped in better characterization of the lesion. MDCT owing to its multiplayer or image reconstruction and deformation properties added in the detection of multifocal lesions and early detection of focal lesions in the presence of underlying liver disease. Triple-phase MDCT was very sensitive in diagnosing all the cases where there was typical enhancement pattern for the indivision lesion concerned. Triple-phase MDCT of liver is a standardized CT procedure which enables in detection and characterization of vast majority of focal lesions in the liver in the presence of different pathological conditions and multi-level disease. These are my references. Thank you.