Are there any factors that can cause a fibroscan to underestimate fibrosis/cirrhosis, or is a low score generally reliable?

Fat / obesity: Fibroscan uses an ultrasonic shear wave to check the liver for "elasticity". Since it is an ultrasound-based technique, anything that interferes with sound waves reduces reliability. Excess fat & water from obesity or ascites can do this. Also,"mid-range" values do not correlate with biopsy results but early (or no) fibrosis & advanced fibrosis r reliably detected with Fibroscan. Hope this helps.

Fibroscan is new: "Fibroscan" is a technique and uses a machine which is relatively new It's backers claim that the machine measures the "elasticity" of the organ this picking up fibrous changes earlier than CT/MRI scanning. This data is too new to have much confidence in it and if you are worried Liver function tests/Imaging with standard tools is suggested Hope this helps Dr Z