AN EVALUATION OF VARIATIONS OF THE RIGHT HEPATIC ARTERY USING MULTI DETECTOR COMPUTED TOMOGRAPHY (MDCT) Pallavi * 1 , Ravichandra V 2 . *1 Assistant Professor, Department of Anatomy, Father Muller Medical College, Mangalore, Karnataka, India. 2  Associate Professor, Department of Pharmacology, K.S Hegde Medical Academy, Deralakatte, Mangalore, Karnataka, India. Address   for   correspondence:   Dr.Pallavi,   Assistant   Professor,   Department   of   Anatomy,   Father   Muller   Medical   College,   Kankanady,   Mangalore   –   575002, Karnataka, India. E-Mail:  dr.m_pallavi@yahoo.co.in ABSTRACT: Background:    The   study   on   the   variations   of   the   hepatic   artery   dates   back   to   1917   when   Lipshutz   B   reported   the   variations   of   celiac   artery   and   its   branches. These   variations   result   from   the   persistence   and/or   abnormal   regression   of   parts   of   primitive   arterial   system.   Owing   to   the   greater   variability   of   the   right intrahepatic   vascular   anatomy,   resections   extensively   involving   the   right   hepatic   lobe   rely   heavily   on   preoperative   assessment   of   origin   and   branching pattern of right hepatic artery (RHA). Aim:    The   present   study   was   intended   to   provide   numerical   parameters   of   the   frequency   of   occurrence   of   the   right   hepatic   artery   variations   in   a   given   study population. Materials   and   Methods:    The   present   study   was   conducted   using   Multi   detector   computed   tomography   (MDCT)   angiography   images   of   200   patients,   in   the department   of   Radiodiagnosis   and   imaging,   Kasturba   medical   college,   Manipal,   India.   MDCT   arterial   phase   images   of   abdominal   aorta   done   for   various clinical indications routinely were evaluated to describe the origin and branching pattern of the RHA. Presence of an accessory RHA was documented. Results:    Variations   in   the   origin   of   the   RHA   were   encountered   in   26   cases   (13%)   out   of   which,   16   were   male   patients   and   10   were   female   patients.   RHA arose   from   the   superior   mesenteric   artery   (SMA)   in   19   cases   (9.5%),   directly   from   the   coeliac   trunk   in   one   case   (0.5%)   and   aorta   in   one   case   (0.5%). Accessory RHA arising from the SMA was seen in 5 cases (2.5%). Conclusion:    A   detailed   knowledge   of   the   hepatic   angioarchitecture   is   considered   a   prerequisite   for   planning   and   conducting   uncomplicated   biliary   tract operations,   liver   transplants,   chemo-embolization   of   a   liver   neoplasm,   as   well   as   other   procedures   performed   in   this   region.   Hepatic   arterial   anatomy   must be defined precisely to ensure optimal donor hepatectomy and graft revascularization. KEY WORDS: right hepatic artery, variations, MDCT, right hepatic lobe resection, accessory hepatic arteries. References 1 . Frachon SC, Scoazec JY. Vascular development and differentiation during   human liver organogenesis. Anat Rec. 2008;291(Suppl 6):614-627. 2 . Seco   M,   Donato   P,   Costa   J,   Bernardes   A,   Caseiro-Alves   F.   Vascular   liver   anatomy   and   main   variants:   what   the   radiologist   must    know.   JBR-BTR. 2010;93(Suppl 4):215-223. 3 . 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