Acta Biomedica Scientia

ROLE OF TRIPLE PHASE CT IN EVALUATION OF FOCAL LIVER LESIONS IN NON CIRRHOTICS

Seshu Lakshmi Borra1, Madhuri Atluri2, Jahnavi Barla3, D.Ankamma Rao4 and T.Rajeswara Rao5

k.seshulakshmi@yahoo.co.in

Triple phase CT, Focal liver lesions, Enhancement patterns.

Focal liver lesions are discrete abnormalities arising within liver and are increasingly being discovered with the widespread use of diagnostic imaging modalities. Triple phase CT has become the primary imaging modality for focal liver lesions. It is an effective aid in determining the number, location, and nature of such lesions and monitoring their size over time. This study was done to evaluate the usefulness of triple phase CT in detection and characterization of focal liver lesions. Patients are kept nil orally 4 hrs prior to the CT scan. Axial plain sections were taken from the level of lung bases to the level of ischial tuberosities. After contrast administration, Sections were taken in HAP, PVP and Delayed phases in craniocaudal direction from the superior margin to the inferior border of the liver. Dynamic viewing of all reconstructed images is done. Later the lesions are confirmed by biopsy/surgery/usg/follow-up as and when required. Appearance of each lesion in each phase was described on the basis of attenuation and homogeneity of the lesion in comparison to the liver parenchyma in that phase. Of the total 160 focal liver lesions seen in 50 patients, there were 114 hypo vascular lesions accounting for 71.2% of the total lesions and 46 hyper vascular lesions accounting for 29.8% of the total lesions. In our study we had 11 patterns of enhancement, four of the 11enhancement patterns were always due to benign lesions, another five of 11 enhancement patterns were always due to malignant lesions, and other two of the 11 enhancement patterns were due to both malignant and benign lesions. In our study hypo vascular lesions were best detected during PVP and hyper vascular lesions in HAP. The triple phase CT enhancement patterns were 100% sensitive and specific in diagnosing all cases of Abscess, Cysts and intrahepatic cholangiocarcinoma. The sensitivity of Triple phase CT enhancement patterns in diagnosing HCC is 84.3%, Hemangioma 93.0%, FNH 75% and Metastases 6%. There was 100% specificity in diagnosing all the cases only when the individual lesion had typical enhancement pattern. The PVP images are essential for detection of hypo vascular lesions. HAP images are helpful in detecting hyper vascular lesions. Characterization of focal liver lesions based on the enhancement patterns was satisfactory. Triple phase CT of liver is a standardized CT procedure, enables in detection and characterization of focal liver lesions.