
Ultrasound-Guided Visceral Biopsies: Renal and Hepatic Nirvikar Dahiya, MD, William D. Middleton, MD, Christine O. Menias, MD* KEYWORDS Ultrasound Biopsy Renal Hepatic Perivascular Pseudoaneurysm KEY POINTS The basic approach to planning an ultrasound-guided biopsy is similar to performing any other interventional procedure. Visceral organ biopsies are being routinely done these days with excellent diagnostic results. Ultrasound is a safe and reliable imaging modality to provide guidance for the vast majority of biopsies. With good technique, these procedures have a very low complication rate. The authors have provided several related videos at http://www.ultrasound.theclinics.com/. LIVER BIOPSY imaging tests point to a specific focal or diffuse liver disease. Serial liver biopsies may help to Ultrasound-guided percutaneous biopsy of vis- monitor effects of specific therapy or to identify ceral organs in the abdomen has been in effect recurrence of disease.4 for many years. Paul Ehrlich is credited with per- forming the first percutaneous liver biopsy in 1883 in Germany.1 Schu¨ pfer2 in 1907 published Preparation for a Liver Biopsy the first liver biopsy series. Huard and Baron The preparation of a liver biopsy constitutes the popularized liver biopsy for general purposes in major portion of the work needed to execute the1930s. Some of the more contemporary arti- a successful biopsy. The actual act of directing cles reporting ultrasound-guided procedures the needle to the target region and collecting the were written in 1972 by Goldberg and Pollack.3 specimen only constitutes a small component of The basic approach to planning an ultrasound- the procedure itself. A thorough history taking is guided biopsy is similar to performing any other in- imperative before the initiation of the biopsy. terventional procedure. However, there are certain With this, the exact clinical question can be under- complexities specific to biopsy of the liver and stood and the correct biopsy technique (fine- kidney that are addressed in this article. needle aspiration [FNA] vs core needle biopsy) determined; accordingly, the proper needle type Indications for a Liver Biopsy and gauge can be selected. For instance, in The indications for doing a liver biopsy are outlined patients with diffuse liver disease and a coexisting in Box 1. A liver biopsy gives invaluable infor- mass, it may be necessary to biopsy the mass mation regarding the staging, prognosis, and (for diagnosis), the liver parenchyma (as part of management even if clinical, laboratory, or preoperative surgical workup), or both depending Section of Abdomen Imaging, Mallinckrodt Institute of Radiology, Washington University, 510 South Kingshighway, St Louis, MO 63110, USA * Corresponding author. E-mail address: [email protected] Ultrasound Clin 7 (2012) 363–375 doi:10.1016/j.cult.2012.03.004 1556-858X/12/$ – see front matter Ó 2012 Elsevier Inc. All rights reserved. ultrasound.theclinics.com 364 Dahiya et al Box 1 or fresh frozen plasma can be considered dependent Indications for liver biopsy on the clinical evaluation. The decision to proceed can then be based on the location of the mass or Diffuse hepatocellular disease the general condition of the patient. Alcoholic liver disease Once the bleeding profile has been evaluated, it is important to review all the medications the patient is Nonalcoholic hepatic steatosis taking. Some patients may be on long-term antico- Autoimmune hepatitis agulation or antiplatelet therapy, including aspirin, Grading and staging of chronic hepatitis C or warfarin, clopidogrel bisulfate (PLAVIX; Bristol- chronic hepatitis B Myers Squibb [New York, NY, USA]/Sanofi Phar- Heavy metal storage disorders such as hemo- maceuticals [Bridgewater, NJ, USA]), and heparin. chromatosis and Wilson disease The referring physician must then determine if the risk of discontinuing the medicines is worse than Cholestatic liver diseases such as primary biliary cirrhosis and primary sclerosing cholangitis the increased risk of bleeding related to the biopsy. If the medications are to be discontinued, we Abnormal liver function tests follow the guidelines listed in Table 1 to determine Evaluation of efficacy or adverse effects of the period of time they are withheld. Regarding drugs such as methotrexate subcutaneous heparin, the liver biopsy can be per- Fever of unknown origin formed if the PTT is within normal limits. Readers Hepatosplenomegaly of unknown origin are advised to consult with their respective hema- tologic and clinical departments to ascertain Liver transplant rejection guidelines for coagulation parameters and man- Focal liver disease agement of time for holding anticoagulants before Primary hepatocellular carcinoma, doing a biopsy. Many times such decisions are made on a case-by-case basis. Cholangiocarcinoma An informed consent is obtained before pro- Metastatic disease ceeding with the biopsy. An allergy history to latex Indeterminate mass gloves and lidocaine is established at this time. All the steps of the procedure are explained to the patient in detail so that there are no surprises during the procedure itself. on the clinical situation. In patients with multiple liver masses, prior workup may point to specific lesions Procedure of Doing the Liver Biopsy that are worrisome and others that are clearly A critical component of the procedure is choosing benign. If the patient had undergone positron emis- an approach for a liver biopsy. The ideal approach sion tomography/computed tomography (PET-CT) would be to find the shortest course to the target, as part of the workup, it is important to make avoiding lung, diaphragm, and all the vascular a good anatomic correlation between the hyper- structures. However, this is not always possible. metabolic lesion seen on the PET-CT and ultra- For a random liver biopsy, we prefer targeting sound examination. Some of the newer ultrasound the peripheral right hepatic lobe. This region is equipments allow for fusion imaging, whereby an overlaying of the CT, magnetic resonance imaging, or PET can be done with the ultrasound examination Table 1 to accurately identify the target.5 Guidelines for management of anticoagulants Once the clinical question has been understood, before a visceral organ biopsy the prebiopsy workup includes evaluation of the bleeding profile of the patient and a detailed review Suggested Period Suggested Time Frame for of current medications taken by the patient. At our of Discontinuity Restarting Medication institution, we routinely obtain international normal- Coumadin: 5–7 d Resume the day of the ized ratio (INR), platelet count, prothrombin time, procedure and partial thromboplastin time (PTT). Our guide- Plavix: 7 d Resume the next day lines include performing a biopsy when INR is less Ticlid: 10 d Resume the next day than 1.5 and the platelet count is greater than Heparin Drip: 6 h Resume drip 12 h after 70,000/mL. Some institutions take a count of plate- procedure m 6 lets of 50,000/ L as the minimum requirement. Lovenox: 12 h Resume 12 h after If the INR is greater than 1.5 or if the platelets are procedure less than 70,000/mL, a transfusion of platelets and/ Ultrasound-Guided Visceral Biopsies 365 remote from the central hilar vasculature, and cutting-type needles (Vim-Silverman needle and a tamponade effect can be achieved on comple- Tru-cut needle). The cutting-type needles can tion of the biopsy by having the patient to lie in also be spring loaded. Most visceral core biopsies right lateral decubitus position. If a good subcostal are now performed with spring-loaded needles. window is available, it is our first preference. These needles can be further classified as side However, in most cases an intercostal approach notch or end cutting (Figs. 3–6). is performed, in which the needle traverses the They can also be classified as automatic or diaphragm and pleural space. Care should be semiautomatic. The semiautomatic needles allow taken to avoid the aerated lung. For this reason, one to manually advance the side-notch needle we generally position the needle inferior to the into the target. The biopsy is performed if the oper- transducer, so that shadowing from the lung can ator is satisfied with the placement of the notch in be visualized and avoided before the needle is the target. The automatic needle obtains the core advanced into the liver. When using the intercostal without providing the option of manual advance- approach, the needle is directed over the ribs as ment. With this type of needle, it is critical to the vascular bundle courses along the inferior make accurate measurements of the target size edge of the ribs (Fig. 1). to select an appropriate predefined length for A random biopsy of the left hepatic lobe is per- core biopsy. The end-cutting needles used in our formed when the right hepatic lobe is not feasible. department yield full core specimens at lengths In most cases, the lateral section of the left lobe is of 1.3, 2.3, or 3.3 cm, whereas the semiautomatic targeted in a manner such that the left portal vein side-notch needle yields a partial core specimen at and artery can be avoided. Color Doppler is used a length of 1 or 2 cm. This can vary depending on as a mapping tool for all our biopsies. the biopsy device manufacturers. If the biopsy Care is taken to minimize the risk of bleeding by device that is chosen has a loud clicking sound trying to take the maximum length of the core while performing the procedure, it is best to tissue in the first pass. In cases in which the biopsy make patients aware of this so that they do not is of a target lesion within the liver, many have sug- get startled during the procedure when they hear gested choosing a biopsy path that courses the sound. In terms of guidance, the choice is through a part of the normal liver before reaching between using a mechanical guide attached to the target.
Details
-
File Typepdf
-
Upload Time-
-
Content LanguagesEnglish
-
Upload UserAnonymous/Not logged-in
-
File Pages13 Page
-
File Size-