Temporary page for CDC Ultrasound: Protocol for Abdomen including AAA and Doppler (Revised March 2007 by Hamid T)
I.     Abbreviations for Annotation
  • ML: structures located close to the midline of abdomen  
  • RT: structures located in the right upper abdomen
  • LT: structures located in the left upper abdomen
  • BL: urinary bladder
  • RLQ: structures located in the right lower abdomen
  • LLQ: structures located in the left lower abdomen

II.    Accompanying Family Member
  • Family member of the patient may stay in the ultrasound room per patient’s request.

III.   Patient Preparation
  • Patient should be fast for 6-8 hours prior to the examination. Water or juice may be allowed.

IV.   Equipment
  • Antares: CH6-2 MHz curvilinear transducer. Set the multi frequency at 6 MHz to start with.
  • Use the optimized presets (marked with a “*”) from the preset menu on the monitor.
  • Turn harmonic imaging on ONLY for fluid-filled structures, such as gall bladder, bile ducts and cystic lesions. However, if you
    have to use harmonic imaging for solid structures, make sure that you provide similar non-harmonic images of the same
    structure as well.

V.    Recommended Views
A.    Midline Vessels: Abdominal Aorta
  • Image aorta in longitudinal plane from diaphragm to bifurcation to rule out aneurysm, plaque disease, and retroperitoneal
    adenopathy.
  • If an abdominal aortic aneurysm (AAA) is present, document origin of the renal arteries, if possible.
  • If requested to rule out AAA specifically, add additional images of the aorta in transverse plane at the bifurcation with and
    without color Doppler.
  • If an AAA is present, image the AAA with color Doppler to demonstrate if the AAA is partially thrombosed or not.
  • The maximal AP diameter of the AAA (outer wall-to-outer wall) should be measured on the longitudinal plane. In addition, the
    length of the AAA in longitudinal plane and the width of the AAA on the transverse plane should be measured.
  • If an AAA is present, include images of the common iliac arteries in longitudinal and transverse planes with color Doppler. If
    AAA involves the iliac arteries, measure the maximal AP diameter of the iliac artery on the longitudinal plane.

B.   Midline Vessels: Inferior Vena Cava (IVC)
  • Image IVC in longitudinal plane at the level of diaphragm.
  • If the patency of IVC is being questioned, the entire length of IVC should be interrogated with and without color Doppler.
  • Dilated IVC with lack of respiratory movements should be reported.
  • Vena cava filters, interruption devices or catheters may need to be localized with respect to the hepatic and/or renal veins.

Image Optimization Tips
  • Evaluation of the aorta and IVC may be performed using the transcoronal approach if the midline windows are obscured.
  • Also you may turn the "Clarify" feature on to image the midline vessels in technically difficult exams.

C.  Midline Vessels: Celiac Axis
  • Interrogate the region of the celiac axis for adenopathy.
  • Transverse image of the celiac trunk to include its branches (splenic and proper hepatic arteries) when indicated.

D.   Midline Vessels: Superior Mesenteric Vein (SMV)
  • Longitudinal image of the SMA to include portal confluence and neck of the pancreas.

E.   Pancreas
  • Image in transverse plane; include the common bile duct (CBD) and the gastroduodenal artery (GDA) lateral to the head of
    the pancreas.
  • Assess the pancreatic duct for dilatation; evaluate peripancreatic region for lymphadenopathy or vascular abnormalities.
  • An adequate number of images should be obtained in order to thoroughly demonstrate the head, body, and tail of the
    normal pancreas and/or any abnormalities.

Image Optimization Tips
  • After consulting with radiologist, views of the pancreas can be enhanced by having the patient drink a large glass of
    degassed water through a straw or by administration of an oral contrast media that absorbs gas.
  • Fluid or oral contrast media can only be administered if the patient is not scheduled for other studies that require they be
    NPO.

F.   Liver
  • Carefully sweep through the liver in the longitudinal plane from left to right and in the transverse plane from cephalad to
    caudad. Observe texture changes.
  • Evaluate for focal or diffuse abnormalities of the liver and for dilated intrahepatic bile ducts. Determinate the location of focal
    abnormalities in the right lobe of liver (RLL) or in the left lobe of liver (LLL).
  • In a normal liver the image documentation should include:
  • longitudinal image of the LLL to include the caudate lobe, ligamentum venosum and the IVC
  • transverse image of the LLL to include the caudate lobe, ligamentum venosum and the left branches of portal vein
  • transverse image of the RLL at the level of 3 hepatic veins,
  • transverse image of RLL at the level of  portal veins
  • transverse image of RLL to include right hepatic vein and right dome of diaphragm. This can be achieved from sub-
    costal windows.
  • transverse image of RLL to include anterior and posterior branches of right portal vein
  • longitudinal image of RLL to include the right pleural space and the right kidney.
  • longitudinal image of RLL to include main portal vein and porta hepatis
  • In an abnormal liver, additional images including Doppler will be required in relation to the location and the characteristic
    feature of the abnormality.
  • If the patient is positive for HBV, HCV, or HIV, there should be at least one image of the liver surface using a high frequency
    linear transducer (L7-3 or L9-4 MHz) whether there is ascites or not.
  • In describing liver echogenicity, instead of using ambiguous terms such as “heterogeneous liver”, describe the liver if it is
    cirrhotic, nodular, or compatible with chronic active hepatitis.


Doppler Examination of the Liver
  • Doppler examination of the portal vein include: Color and PW Doppler of MPV, RPV (or its anterior and posterior branches)
    and LPV.  
  • Doppler examination of hepatic veins includes color and PW Doppler of all 3 branches of hepatic veins as well as IVC
  • Doppler examination of the hepatic artery includes color and PW Doppler of the hepatic artery at the level of porta hepatis.
    Velocity calculation of the hepatic artery is not accurate for determining the stenosis. However, color bruit artifact or a tardus
    parvus waveform may be suggestive of stenosis or compression by external masses.

Portal Hypertension Protocol
  • Color Doppler image of the umbilical vein should be documented whether it is recanalyzed or not.
  • If the umbilical vein is visible with color Doppler, then, a PW Doppler should be performed to demonstrate the characteristics
    of the waveform.
  • Color Doppler image of the GE junction should be documented whether there are obvious varices or not.
  • Interrogation of the portal confluence with color Doppler should be performed to rule out presence of dilated coronary vein.
    If visible, then, a PW Doppler of the dilated coronary vein is required to demonstrate the characteristics of the waveform.
  • Color and PW Doppler of MPV, RPV, LPV, splenic vein at the level of pancreatic tail and splenic hilum, and SMV should be
    performed to assess if:
  • The thrombosis is focal or complete
  • The flow is to and fro, reversed or pulsatile
  • There is cavernous transformation of the portal vein at the porta hepatis
  • There are porto-systemic shunts
  • Color Doppler image of the splenic hilum should be documented whether the spleno-renal shunt is visible or not.
  • RI index of the hepatic artery and the peak systolic acceleration time may some times be helpful to assess the hemodynamic
    changes in relation to the etiology of the portal hypertension.

Image Optimization Tips
  • To perform Color or PW Doppler of the MPV, use a window from the right intercostal space through the RLL.
  • Lower the color velocity scale to 10 cm/sec and increase the color gain in order to see the sluggish flow in the small varices
    at the GE junction or splenic hilum.
  • If there is no flow in the region of umbilical vein with curvilinear transducer, repeat the color Doppler interrogation with a
    linear transducer (L7-3 MHz).

G.   Gall Bladder/Biliary Tract
  • Equipment: Make sure CH6-2 MHz curvilinear transducer set at 6 MHz, with harmonic and compound imaging on.
  • Interrogate the gall bladder (GB) in longitudinal and transverse planes.
  • Evaluate for stones, polyps, wall thickness and other abnormalities, pericholecystic fluid, positive sonographic Murphy’s
    sign, and intrahepatic duct dilatation.
  • In symptomatic patients with gall stone, sonographer must make an attempt to determine whether the stone is mobile or not.
  • Common duct must be measured at the porta hepatis, across the hepatic artery.
  • If intrahepatic ducts are dilated, the entire length of common duct should be interrogated and, if possible, imaged for the
    presence of stone or mass
  • If GB is distended but the common duct is not dilated, the neck of GB should clearly be imaged to rule out stone in the neck
    or cystic duct.
  • The distal common bile duct in the head of pancreas should be imaged.
  • In non-symptomatic patients with contracted GB, the patient should be asked whether she/he had fatty food prior to the
    ultrasound examination.
  • Color Doppler may be helpful to identify cholesterol deposits in the GB wall by demonstrating twinkle artifact.
  • Presence of color Doppler flow in the GB wall is not a reliable sign for acute cholecystitis.

Image Optimization Tip
  • Additional patient positions may be used as necessary, such as upright, right lateral decubitus (RLD) or with the patient on
    his/her hands and knees to demonstrate stones trapped in the gallbladder neck.  
  • Linear transducers may be helpful in the precise assessing of the GB wall thickness.

H.    Kidneys/Urinary Tract
  • To avoid missing pathology, sweep slowly and carefully through each kidney prior to recording images.
  • Image both kidneys longitudinally from medial to lateral and transverse from superior pole to inferior pole.
  • Include one image of the right kidney and the liver to compare the echogenicity of the kidney to that of the liver and to
    document the right adrenal region.
  • Include one image of the left kidney and the spleen to compare the echogenicity and to document the left adrenal region.
  • At least one image of the urinary bladder should be included in addition to the kidney images. If hydronephrosis is noted,
    include color Doppler of the urinary bladder to demonstrate urine jets.
  • If there is hydronephrosis, also assess the ureter for hydroureter and its extent
  • If there is hydronephrosis, also assess if there is any debris (echoes) within the ureter or collecting system.
  • Color Doppler may be useful to assess AVF and AVM in kidneys.

Image Optimization Tips
  • Evaluation of the kidneys from more than one approach will enhance visualization of the peri-renal space and provide
    information about lesions that extend from the edge of the kidney.
  • Generally, the kidneys are imaged on deep inspiration.
  • If there is a small non-shadowing stone, turn the compound imaging off, use a higher frequency transducer, turn the
    harmonic imaging on, narrow the sector (the sonographic field of view), and apply more than one focal zone, try color
    Doppler to look for twinkle artifact specially at the UVJ, or if the renal sinus is very echogenic.

Doppler Examination of Renal Artery
  • Doppler examination of the renal arteries is not reliable due to limited accessibility to the renal arteries, variant branches of
    renal artery, Doppler angle correction, patient's size and ability of patient to follow breathing instructions.
  • Aliasing and bruit artifact with color Doppler at the renal hilum may be suggestive of renal artery stenosis.
  • Measurements that can be performed on PW Doppler of renal artery include an angle-corrected peak systolic velocity, a
    resistive index, and/or acceleration times, and evaluation for delayed systolic peak (tardus parvus waveform).
  • An angle-corrected peak systolic velocity may also be measured in the aorta at the level of the renal arteries.
  • Doppler of the main renal vein (MRV) should also be included to evaluate the vein for patency.
  • Slow acceleration time of the PSV (>0.12 sec) may be suggestive of renal artery stenosis.

Doppler Examination of Renal Vein for Thrombosis
  • Perform color and pulsed-wave Doppler of the main renal vein (MRV).
  • If thrombus is present, evaluate the IVC.
  • The PW Doppler of the renal artery should also be included to determine the resistive index. A damped arterial flow pattern
    with no diastolic flow throughout the entire cortex may indicate a complete renal vein thrombosis.


I.     Spleen
  • Scan through the spleen in longitudinal and transverse planes and document the images.
  • Measure the length of spleen.
  • Include one image that demonstrates the left pleural space.
  • Include one image that demonstrates the upper pole of the left kidney and spleen

Image Optimization Tips
  • Imaging of the spleen is often best performed in supine with the patient’s left side slightly (about 10-15 degrees) turned up.
  • The spleen is best imaged on quiet respiration.

J.    Bowel including Appendix
  • Equipment: linear transducer (L7-3 or L9-4 MHz), compound imaging with/without harmonic imaging.
  • The bowel may be evaluated for wall thickening, dilatation, inflammation, masses, and diverticulosis.
  • If abdomen is tender, start with graded compression over the area of maximum tenderness, as determined by interrogation
    of the patient.
  • Identification of the cecum, terminal ileum, iliac vessels, and iliacus muscle are helpful landmarks for identification of the
    appendix.
  • The appendix originates from the tip of the cecum and is usually located inferior and slightly medial to the cecum.
  • Longitudinal and transverse images of the appendix should be obtained and an AP measurement should be documented.
  • Images of the tip of the cecum and the terminal ileum should be included.
  • Demonstrate the entire length of the appendix to rule out segmental appendicitis.
  • Document any peri-appendiceal fluid collections and the presence of appendicolith.
  • Color Doppler may be helpful to demonstrate hyperemia. However, if the appendix is gangrenous, flow will not be present.
  • In female patients, this examination should also include views of the uterus and ovaries to rule out a gynecological cause for
    right lower quadrant (RLQ) pain.
  • In all patients, this examination may also include the right upper quadrant (RUQ) to rule out other sources of the patients
    symptoms.
  • Image the lower quadrants to rule out presence of free fluid.

Doppler Examination of Mesenteric Arteries
  • Doppler examination of mesenteric arteries is limited by the accessibility to the mesenteric arteries, Doppler angle
    correction, patient's size and ability of patient to follow breathing instructions.
  • Evaluation may include the superior mesenteric artery (SMA), inferior mesenteric artery (IMA), celiac axis, and aorta.
  • There are no reliable scientific sonographic criteria for stenosis of the mesenteric arteries, however, visualization of color
    bruit artifact, tardus-parvus waveform and significant amount of plaque may be suggestive of a severe stenosis.
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