pancreas normal
scan plane.
normal pancreas and surrounding anatomy
sagittal scan plane of the pancreatic head.
head of pancreas.
sagittal view.
fatty infiltration of the pancreas
a common finding is sparing of the uncinate process due to it’s different embryologic origins.
fatty infiltration of the pancreas with focal sparing of the uncinate process.
you can see no mass effect or compression of the cbd. a progress u/s to confirm or, if in doubt, a double contrast ct can help confirm this finding.
improved visualisation of the pancreas after a water load
give the patient an oral waterload (2-3 glasses) to displace gas in the stomach. initially, microbubbles from swallowing will swirl in the water and then clear. now re-scan the patient in a slight right decubitus position to allow the water to settle at the pyloris and duodenum. alternatively scan the patient erect.
the water is used as a window to look through when it is in the stomach and duodenum.
this picture shows the stomach and duodenum lying anterior to the pancreas. this is why the water is so successful in helping visualise the pancreas.
by bruceblaus. when using this image in external sources it can be cited as:blausen.com staff (2014). “medical gallery of blausen medical 2014”. wikijournal of medicine 1 (2). doi:10.15347/wjm/2014.010. issn 2002-4436. – own work, cc by 3.0, https://commons.wikimedia.org/w/index.php?curid=28909219
the pancreas fasted and the 2nd image is after 2 glasses of water.
to learn about pancreatic embryology
to learn about pancreatic anatomy and histology.
role of ultrasound
- always tailor your scan to the clinical signs.
- always take a thorough history including previous cancer,diseases,blood results,family history and past surgery.
- perform an initial overall scan without imaging to get an idea what pathology there might be and how it might relate to the patients current complaint.
limitations
- often you will have problems with bowel gas overlying the pancreas.
ways to overcome this include :
- deep inspiration / expiration
- distend the abdomen against the probe. (ask the patient to push their stomach out as if they are pregnant!)
- give the patient an oral waterload (2-3 glasses).the water is used as a window to look through when it is in the stomach and duodenum.
- scan with the patient erect.
- roll the patient into a rt lateral decubitus position and scan coronally using the spleen as a window to view the splenic tail.
patient preparation
- fast for 6 hours. no food or drink.no smoking.
- preferably book the appointment in the morning to reduce bowel gas.
equipment setup
- highest frequency curved linear array probe as possible.
- start with 6mhz and work down to 2 or 3 for larger patients.
- assess the depth of penetration required and adapt.the gallbladder should be able to be scanned using a 7mhz as it is so superficial.paediatric and thin pts should be scanned with a 7mhz also.
common pathology
- adenocarcinoma
- pseudocyst
- pancreatitis
- fatty change
- insulinomas
- pancreatic artery aneurysm/calcification
- cystic fibrosis
- congenital / acquired cysts
scanning technique
- begin transversely, high in the epigastrum.
- you may need to apply enough pressure to help displace bowel gas.
- adjust image depth so the aorta is at the bottom of the screen.
head of pancreas – use both transverse & sagittal planes as the head can be quite long and continue left caudally for several centimeters.
body of pancreas – transverse probe. use the splenic vein to help identify the pancreas superficial to this.
tail of pancreas – start with the probe transverse then angle the heel of the probe cephalad and left as the tail can be sitting up under the spleen. thus the spleen can be used as a window and a left intercostal coronal approach can also be utilised.
ultrasound appearances
- normal appearance is usually homogeneous and almost isoechoic with the liver.
- it is frequently hyperechoic compared to the liver because of fatty infiltration.
size
- varies with age and history.
approximate normal measurements are:
- head 35mm (anterior to posterior)
- neck 10-15mm
- tail 20mm
basic hardcopy imaging
- the normal anatomy.
- any pathology found, in 2 planes.
- include measurements and any vascularity.