**2. Historical landmarks and recent developments in liver biopsy**

The first written documented report of a successful liver biopsy was made by Paul Ehr‐ lich in the book "On diabetes" published in 1884. He published an account of the proce‐ dure performed in 1880 in Berlin, along with graphical illustrations of the instruments and the liver samples collected. This came detailed account was based on previous theo‐ retical advantages of this technique discussed by the French physician AGM Vernois in 1844, who in turn based his assumption on successful procedures performed for punctur‐

ing purulent echinococcus, as early as 1825 (Récamier) and 1833 (Stanley). Cytology was reported as a diagnosis method for liver disease by L. Lucatello (in Rome) in 1895, while F. Schupfer performed liver and spleen biopsies with a thicker needle twelve years later, in 1907. This new approach provided cylindrical-shaped tissue samples which could be histologically prepared and analyzed [1].

**3. Modern liver biopsy techniques and sampling adequacy**

All modern percutaneous liver biopsy techniques have rapidity as a common denominator. Either cutting or suction needles can be used for transthoracic or subcostal biopsy, either af‐ ter palpation or imaging assessment of the puncturing zone, or, preferably, under continu‐ ous image guidance. The transthoracic approach is the preferred method used, under realtime US or (more rarely) CT guidance and after a thorough imaging investigation of the liver and puncture route. All percutaneous methods imply two phases, one extra-hepatic corresponding to the needle puncturing the skin and reaching the needle, and a hepatic stage in which the needle passes the liver capsule, collects the parenchyma material, and is swiftly extracted. It is considered a relatively safe procedure, complication rates varying be‐

Risks and Benefits of Liver Biopsy in Focal Liver Disease

http://dx.doi.org/10.5772/52620

87

Trucut needles and their modified versions driven by spring-loaded biopsy guns are in‐ creasingly used and are the instruments of choice in many centers worldwide, especially in Europe [7]. Needle diameters vary between 1.20 mm to 1.60 mm, smaller calibers being used

Suction needles are less expensive and their operation allows for rapid intra-hepatic han‐ dling, thus being easier to use and possibly imply less bleeding-related complications. The most widespread types are the Menghini, Jamshidi and Klatskin needles, which remained virtually unchanged since their introduction in the second half of the last century. The maxi‐ mum required time for a complete syringe suction of the cytological material and the con‐ secutive needle retraction is 0.5 seconds. The intrahepatic phase is reduced to as low as 0.1

Image guidance has become mandatory in centers where the gastroenterologist can perform his or her own US exam. Real-time surveillance of the procedure greatly decreases the risk of complications (such as bleeding) and minimizes post-procedural complaints such as pain or hypotension. Hepatologists in the United States usually prefer to have a radiologist per‐

The transjugular route is preferred when the risk for complications is high and therefore a percutaneous approach is not considered safe enough for the patient. Patients with clinical ascites, known hemostatic defect, cirrhotic liver with clinical signs of organ deficiency (smaller size and increased palpatory stiffness) or morbid obesity are usually prime candi‐ dates for this approach. Another situation when the transvenous approach is preferred is

The resources needed for this procedure are higher than percutaneous approaches; howev‐ er, complication rates are lower (2.5% up to 6.5%) according to some authors [9], with mor‐ tality rates of approximately 0.09% in high-risk patient groups [10]. The expertise of the

when additional pressure measurements in the hepatic vein are required [8].

**3.1. Percutaneous biopsy**

tween studies, from 0.75% up to 13.6% [6].

when a high risk of complications is suspected.

seconds when the needle is operated by an expert practitioner [8].

forming the procedure under CT or US guidance [8].

**3.2. Transjugular (transvenous) biopsy**

Other scarce accounts of successful procedures followed in the next couple of decades (Oli‐ vet, 1926; Huard 1935; Silverman, 1938; Baron, 1939; Kofler, 1940; Dible, 1943), using differ‐ ent aspiration techniques performed with different modified biopsy needles [1].

A new stage in modern liver biopsy techniques was reached when, in 1957 and repeated in the following year, Menghini performed and reported on the first "one-second needle biop‐ sy" performed with a special small caliber needle with no trocar and a sharp bevel. This was the first time needle liver biopsy was introduced worldwide as a praised diagnostic techni‐ que capable of providing enough histological material for an accurate interpretation of the pathological changes present in the parenchyma [1].

Following this radical advancement, liver biopsy became more spread and the technique evolved once modern imagistic methods allowed for better and safer puncturing of the liver parenchyma. Thus, the technique entered the image-guided age of investigation per‐ formed under computed tomography (CT) or ultrasound (US) real-time screening. Re‐ ports from Denmark, China, the United Kingdom, France or the United States of America populated the 1960–1980 literature, once the technique became widespread and fully acknowledged by the academic community. Its utility in diagnosing liver diseases and later on in staging hepatitis or malignancies was undisputed for entire decades of the 20th century [1].

Recent advancements, based on the advent of new imagistic high-accuracy techniques based on both US and CT/RM approaches, highly diminished the role played by this invasive in‐ vestigation. The term "virtual biopsy" became more and more present in recent literature, once both doctors and patients alike became more confident and were introduced to these high-yield methods, such as Transient or Acoustic Radiation Force Elastography. Moreover, advanced serum markers (such as, for example, the Fibrotest-Actitest battery of tests) allow for an accurate non-invasive staging in hepatitis. The introduction of arterial uptake con‐ trast-enhanced US and CT/RM techniques substantially decreased the role of biopsy in diag‐ nosing liver biopsy [2–4].

However, histology remains one of the most accurate methods for evaluating liver paren‐ chymal changes, and is always used in malignancies when the diagnosis is uncertain or when other non-invasive methods fail to provide an accurate staging for hepatitis. Along with these non-invasive techniques came a revolution in in-situ biopsy methods. Such is probe-based confocal laser endoscopy (pCLE), which uses miniaturized probes connected to a laser source through fiber optics, small enough to fit inside a biopsy needle, thus provid‐ ing rapid live assessment of liver architecture [5].
