Sunday, September 5, 2010

Liver - Sonogram

Normal Liver

Transverse scan (TS) 


Rt lower lobe of liver show homogeneous hepatic parenchymal echo pattern as isoechoic or slightly echogenic than renal parenchymal.

Rounded echogenic areas represent fibrofatty tissue surrounding ducts and vessels too small to be imaged.






Longitudinal scan (LS)

Homogeneous liver echo pattern as isoechoic or slightly less echogenic than pancreas.

Liver - Anatomy

Normal Liver 


  • Lies in upper quadrant of abdomen
  • Suspended from right hemidiaphragm
  • Have 3 lobes: (right, left, caudate lobe)
  • Right intersegmental fissure divided  RT lobe into anterior and posterior segment 
  • Left intersegmental fissure divided LF lobe into medial and lateral segment
  • Caudate lobe locate posterior of liver





Liver occupies the Rt hypochondrium, the greater part of epigastric region, & extends in varying degrees into Lf hypochondrium as far as mammary line.

Lateral segment of Lf lobe & the length of Rt lobe determine contour and shape of liver. 

Liver can described as irregular, hemispheric, or wedge shape.






Caudate lobe
  • Situated at posterior of liver
  • Posterior border: IVC
  • Anterior border: Ligamentum venosum
  •  

Abdomen and superficial structures

 By Diane M. Kawamura pg 120

Saturday, September 4, 2010

Liver - Technique

Normal Liver


Technique

  • Patient: Fasting 6 hours (so the bowel gas limited & GB is not contracted.)
  • Position: Supine, right anterior view (bec liver is tucked beneath the lower right ribs, a transducer with a small scanning face allowing an intercostal approach, is valuable.)
  • Breathing: Suspended inspiration (so able to see dome)
  • Transducer: Sagittal, transverse, coronal, subcostal oblique



To make the liver more accessible, patients need:

  • Raise the right arm above the head (to draw the rib cage upward)
  • Supine position
  • Deep breath and hold (to expand the abdomen)
Transducer/ Scanning approach:


                              
































Scanning down the left border of liver (TS)


Liver TS scan: Center of liver














*Place the transducer in the epigastrium region to the left of midline, for imaging LF hepatic border*

Liver TS scan: Right lobe


* Hold transducer in a slightly oblique position, parallel to the costal margin *


Step for Liver intercostal scan:

  1. Scan through the liver in fan-shaped pattern
  2. Slide the transducer along the intercostal space & scan through
  3. Move transducer to next intercostal space & scan through

Liver intercostal scan