Overview
Ultrasound – the magic of transforming the inside beauty of the human body into an outside picture. Piezoelectric crystals and recently other modalities are drawing a painting from human organs, vessels, muscles and much more. An amazing diagnostic tool – fast, relatively easy to learn and, by bringing to perfection, essential for treating patients in different medical fields
In german-speaking European countries communities such as OEGUM in Austria, DGUM in Germany and SGUM in Switzerland provide ultrasound training as well as medical research. They are also responsible for developing and enhancing ultrasound guidelines to continue the improvement of medicine. Internationally spoken, there are much more organisations and communities that provide ultrasound training and literature for ultrasound-interested medical working staff. Examples are the AIUM - the American Institute of Ultrasound in Medicine or the BMUS - the British Medical Ultrasound Society.
Usage
Abdominal ultrasound is one of the most widespread uses of ultrasound in the medical field. Most commonly used in internal medicine, other specialties such as GPs, pediatricians or as part of eFAST trauma surgeons and anaesthetists benefit from the knowledge of abdominal ultrasound to evaluate patients. For abdominal pathologies, ultrasound should be the preferred diagnostic tool as it is fast, the machines are easily available and with the lack of radiation it is not harmful to the patients. One of the greatest advantages of all ultrasound techniques is the fact that pathologies are detected in a noninvasive way. Therefore it is a huge benefit for the patient as well as for the operateur.
Indication
Symptoms:
- Pain in the upper abdomen
- Pain in the lower abdomen
- Diffuse stomach pain
- Diarrhoea, obstipation
- Unknown fever
- Palpable lymph nodes
- Insufficiency of the kidneys
- Hepatosplenomegalia
- Ascites
- Jaundice
- Palpable resistances
Professions
- Gastroenterology: Hepatitis, cirrhosis of the liver, metastases, lesions of the portal vein, pancreatitis, pancreatic cysts, lesions of the spleen (cysts, trauma,...), infections and/or stones of the gallbladder and the cystic duct or common bile duct, tumours of the stomach and bowl, appendicitis, colitis, etc..
- Surgery: Appendicitis, tumours in the bowl, liver, stomach, pancreas, chronical infection of the gallbladder or stones, etc. Pre/post evaluation of transplantation.
- Oncology: Numerous tumours and carcinomas in the abdomen.
- Internal Medicine: Pathogenic changes of the aorta (hypertension, atherosclerosis) and arteries, vena cava and peripheral veins.
- Nephrology: Diseases and lesions in the kidneys and urinary bladder (infections, insufficiencies, tumours, metastases).
- Urology: Stones, tumours or infections of the bladder, free fluid in the pouch of Douglas, etc..
- Endocrinology: Diabetic lesions in the pancreas, pancreatic tumours, etc..
- Trauma surgery: Free fluid in the abdomen (FAST).
- Thoracic surgery: Pleura lesions (tumours, effusion).
- Pediatrics: All lesions in the child’s abdominal organs.
- Anesthesiology: Patient’s fluid volume changes, FAST, etc. Ultrasound guided invasive procedures.
- Radiology: Diagnostic tool for all mentioned above.
Abdominal ultrasound – step by step
The kick off tricks
Always use the right probe and a good position to start your examination. Your transducer of choice is the curved array probe, because your organs you want to screen lie deep within the abdomen. Get your machine ready with an optimal depth and gain setting. Place the focus in the region of interest. Overall, with the optimal settings you will be able to minimize artefacts and hypo – or hyperechoic structures. Remember to get your patient in a good position (supine, left lateral, right lateral) with one of your hands on the patient and the other one on the ultrasound machine.
For the sonography of the vessels within the abdomen, e.g. IVC or the aorta, the usage of various Doppler studies is indicated. With these easy tools one can differentiate between vascular and nonvascular structures within the abdomen. For differential diagnosis in e.g. gallbladder cancer or vascular complications in acute pancreatitis, Doppler in abdominal ultrasound diagnostics provides an excellent diagnostic tool.
A guided way
The following steps are a suggestion to screen the abdominal parts one by one. You can always change the sequence but it is advisable to stick with your choice in order not to miss any view or organ.
Upper abdomen - horizontal view
To detect the longitudinal axis of the pancreas and the lienal vein as well as horizontal axis of the superior mesenteric artery, the Aorta and inferior Vena cava.
Upper abdomen - longitudinal view
For screening the abdominal aorta with the coeliac trunk and the superior mesenteric artery as well as the left lobe of the liver
Upper abdomen - right side
Use your probe to screen organs always in two axis – longitudinal and horizontal. This view screens the right kidney as well as the right lobe of the liver and the psoas muscle. For Trauma Surgeons the hepatorenal recessus might be interesting for detection of free fluid (Morison pouch) as well as any possible effusion in the right costodiaphragmatic recess.
Liver venes
By positioning your probe directly under the right costal edge (subcostal view) you can screen the right and the left liver lobe as well as the flow of the liver venes into the inferior Vena cava which looks like a little star. By tilting your probe you can show the ramifications of the portal vein.
Gallbladder – horizontal and longitudinal view
By moving your probe from the longitudinal view of the right upper abdomen right to the middle of the abdomen you screen the gallbladder in its longitudinal axis. Turn your probe 90 degrees to show the horizontal view. Look for wall thickening or stones.
Hepatoduodenal ligament
As a portion of the lesser omentum it shows the three structures of the choledochus duct, the inferior Vena cava and the portal vein in longitudinal axis. You position your probe in an imagined line from the right shoulder to the nable.
Upper abdomen – left side
In this view you show the spleen and the left kidney in horizontal and longitudinal axis. The splenorenal recessus might show free fluid in the left abdomen. By moving your probe upwards you screen the left costodiaphragmatic recess for effusion.
Minor pelvis – horizontal and longitudinal view
Evaluated structures differ from women to men. In women you want to screen the bladder, the rectouterine pouch (pouch of Douglas) and the vagina to look for stones or free fluid. In men you screen bladder, rectovesical pouch and the prostate. The pouch of Douglas or rectovesical pouch is the deepest part in the abdomen.
Tips & Tricks
- A good portion of gel might often be the secret of good abdominal views.
- Always image an organ in a longitudinal and a transverse view not to miss out pathologies.
- Get the patient to inhale to get better views of the spleen
- Ask the patient to lift the arms up to widen the intercostal space and voilá - kidneys and spleen are seen
- Abdominal ultrasound in fasting patients is often easier to perform
- A full bladder is easier to detect - so toilet after ultrasound procedure
Abdomensonographie - Richtlinien [Internet]. OEGUM - Österreichische Gesellschaft für Ultraschall in der Medizin. [cited 2018 Feb 18]. Available from: http://www.oegum.at/ausbildung/sonorichtlinien/abdomen.html
Schmidt G, Beuscher-Willems B, editors. Checkliste Sonographie: 81 Tabellen. 3., vollst. überarb. Aufl. Stuttgart: Thieme; 2005. 476 p. (Checklisten der aktuellen Medizin).
AIUM Practice Guideline for the Performance of an Ultrasound Examination of the Abdomen and/or Retroperitoneum. J Ultrasound Med. 2012 Aug;31(8):1301–12.
SCoR The Society and College of Radiographers, BMUS The British Medical Ultrasound Society. Guidelines For Professional Ultrasound Practice [Internet]. 2017 [cited 2018 Feb 20]. Available from: https://www.bmus.org/static/uploads/resources/SCoR__BMUS_Guidelines_for_Professional_Ultrasound_Practice_Revised_Jan_2018.pdf
Speets AM. Upper abdominal ultrasound in general practice: indications, diagnostic yield and consequences for patient management. Fam Pract. 2006 Apr 4;23(5):507–11.
Gandolfi L, Torresan F, Solmi L, Puccetti A. The role of ultrasound in biliary and pancreatic diseases. Eur J Ultrasound Off J Eur Fed Soc Ultrasound Med Biol. 2003 Feb;16(3):141–59.
Koito K, Namieno T, Nagakawa T, Hirokawa N, Ichimura T, Syonai T, et al. Pancreas: imaging diagnosis with color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography. Eur J Radiol. 2001 May;38(2):94–104.