Dynamic Liver Tests in Liver Disease

"Transient elastography will be measured using a Fibroscan® machine which is manufactured by echosens®. It has a CE mark of 0459.~It is a non-invasive method to accurately measure stiffness of a patient's liver without the need for a liver biopsy. This is measured by an externally placed ultrasound probe which creates an elastic shear wave at 50Hz, and measures the velocity of the echo through the liver tissue. The liver stiffness is measured in kilopascals (kPa). It has been shown to be 99% effective in detecting cirrhosis in hepatitis C and has been shown to correlate with hepatoma production in both hepatitis C and hepatitis B. Values range from - normal \< 9.6 kPa, significant fibrosis 9.6-11.4kPa, cirrhosis \>11.5kPa. It cannot be used in patients with ascites."

The machine to monitor the elimination of Indocyanine green is manufactured by PULSION medical systems (Munich, Germany) and consists of the PulsioFlex monitor and LiMON module. The LiMON module is a finger probe which measure near-infrared wavelengths between 805nm and 905nm. The absorption maximum for Indocyanine green is 800nm and emission at 830nm. This is then used to produce two calculations. The first is plasma disappearance rate of indocyanine green (PDRICG). This is based on working out the constant and backward extrapolation and expressed as a percentage per minute. The other is the retention ratio after 15 minutes (ICG15).