Liver Cleanse and Biopsy
Needle biopsy of the liver, when used appropriately, is a vital diagnostic modality
in the evaluation of hepatobiliary disorders. Percutaneous needle biopsy can be performed
by gastroenterologists or hepatologists with or without the use of ultrasound
guidance. Various techniques of percutaneous liver biopsy have been described and
the choice of technique should be made based upon the clinical circumstances and
the comfort level of the person performing the biopsy. Radiologists, surgeons and
laparoscopists also perform liver biopsies. Regardless of technique, liver biopsy is
generally safe with an overall complication rate ranging from 0.06-0.32% and a
mortality rate of less than 0.01%.
Relevant Anatomy
Thorough understanding of the anatomy of the liver and its surroundings is
essential when performing a liver biopsy. This information may help prevent
complications as well as provide an understanding as to why an untoward event
may occur.
- The liver is the largest solid organ in the body lying largely under the right
lower rib cage. The normal liver span space in the mid-clavicular line is
from the fifth intercostal to the right costal margin. Because of this location,
it is usually not palpable on physical examination. Therefore, careful percussion
is required to accurately determine its location and size. The liver is
covered by Glisson’s capsule and divided into four lobes: right, left, caudate
and quadrate.
- Both superiorly and laterally, the liver is attached to the diaphragm. Anteriorly,
the liver is connected to the anterior abdominal wall and diaphragm by
the falciform ligament. This ligament, which contains the remains of the
umbilical vein, is called the round ligament in its lower end. At its upper
end, the falciform ligament ascends the anterior surface of the liver and
divides the liver into the left and right lobes. The posterior surface of the
right lobe abuts the colon, right kidney and duodenum from the right while
the posterior left lobe abuts the stomach. Reidel’s lobe is a benign
anatomic variant resulting in an enlarged right lobe that propagates
caudally and can be easily confused with pathologic hepatomegaly. The gallbladder
lies against the inferior surface of the right and quadrate lobes.
- Percutaneous liver biopsy is performed by passing a needle through an intercostal
space. The most common space utilized is the interspace between
the 8th and 9th ribs. Intercostal nerves, muscles and vessels run make up the
intercostal space. The anterior intercostal arteries and veins and the intercostal
nerves run along the lower border of each ribs. Percutaneous liver biopsy is thus performed by passing the biopsy needle over the superior
aspect of the rib to avoid puncturing the intercostal vessels and nerves.