**3. Transjugular Liver Biopsy (TJLB)**

TJLB was initially introduced in dogs as an experimental application by Dotter [29]. Rosch [7, 8] then reported its clinical application for transjugular cholangiography in 1973 and 1975. TJLB eliminates the need to traverse the peritoneal cavity and puncture the liver cap‐ sule. Furthermore, this technique is a safer biopsy option for patients with massive ascites, coagulopathy (prothrombin time greater than 3 seconds over the control value), thrombocy‐ topenia (less then 60,000/cm3 ), or those undergoing ancillary procedures such as measure‐ ment of pressures or opacification of the hepatic vein and inferior vena cava. It can also be applied for patients in whom PLB has failed, or those with morbid obesity, a small cirrhotic liver, suspected vascular tumor or peliosis hepatitis, or medical conditions associated with bleeding disorders such as hemophilia for whom PLB is contraindicated [11, 30, 31], as any bleeding is returned to the venous system rather than leaking into the abdomen.

However, there are several particular complications associated with TJLB, including hemor‐ rhage, subcapsular or neck hematoma and ventricular arrhythmia. The rate of such compli‐ cations ranges from 0% to 20% [11]. Hardman et al. [4] reported a large subcapsular hematoma caused by TJLB requiring embolization and prolonged admission. Lebrec et al. [9] also reported a fatal case of intraperitoneal hemorrhage due to perforation of the liver capsule caused by excessive of the needle. Therefore, such forward rotation must be avoided or carefully limited. Furthermore, there have been several direct instances of perforation of the liver capsule that resulted in aspiration of ascitic fluid, bile from the gallbladder, or renal tissue in patients with a small cirrhotic liver. In such patients, TJLB should be avoided or employed only with caution by advancing the needle into the liver parenchyma by only 1 cm instead of the usual 2 cm, or contrast medium should be injected after the biopsy to eval‐ uate the integrity of liver capsule. The major drawback of TJLB is the size of the biopsy specimens obtained; they are generally smaller (p <0.001) and more fragmented (p <0.01) than those obtained by PLB [12]. Pathologically, in terms of the number of portal tracts (p <0.0001) and the utility of specimens for histological evaluation (p <0.05), the quality of TJLB samples appears to be significantly lower compared than those of PLB and LLB specimens [14]. With regard to technical success rate, that of TJLB (82%: 84/102) is significantly lower (P=0.005) than PLB (100%: 100/100) or LLB (99%: 111/112) [14]. However, Bull et al. [10] re‐ ported a success rate of 97% (188/197) in 1983, and a recent meta-analysis including more than 7500 cases revealed a technical success rate of 96.8% [13]. These reports suggest that there is no significant difference between TJLB and others techniques in terms of success rate. The most common reason for failure was inability to catheterize the right hepatic vein. In actual practice, TJLB requires a longer procedure time (40 min) than PLB. A few deaths after TJLB have been reported, with a mortality rate of 0-0.5% [10, 32, 33]; mortality was due to hemorrhage from the liver or ventricular arrhythmia.

Therefore, TJLB should be attempted only by a skilled interventional radiologist or physi‐ cian experienced in catheterization and cannulation of the internal jugular vein due to its more time-consuming nature, use of intravenous contrast, and the need for a dedicated fluo‐ roscopy suite. In fact, TJLB can be valuable in cases for which PLB is hazardous, or when pressure measurement or venography is also required [34]. Despite the smaller biopsy sam‐ ples obtained, the impact of TJLB on clinical decision-making appears to be comparable to that of PLB and LLB. In particular, it may help to determine the need for liver transplanta‐ tion in patients with acute liver failure.
