My Ultrasound tutor- Pancreas

Two types of function for the pancreas

Endocrine and exocrine functions

Exocrine gland

Acts as a Digestive role

• Made by acinar cells.

• Produces digestive enzymes

Types of acinar cells

-Amylase

-Lipase

-Sodium bicarbonate

-Trypsin

Endocrine function

Acts as a Hormone role

• Controlled by Islets of Langerhans, which are clusters of hormone-producing cells:

  • Alpha cells → make glucagon (raises blood sugar)

  • Beta cells → make insulin (lowers blood sugar)

  • Delta cells → make somatostatin (regulates other hormones)

Easy way to remember exocrine and endocrine function

EXOcrine= EXIT thru ducts

ENDOcrine= INTO the blood

Main pancreatic duct

AKA duct of Wirsung

-Travels the length of pancreas and terminates when it meets with the CBD at the ampulla of Vater

-Empties via sphincter of Oddi (major)

Accessory duct

AKA duct of Santorini

-Branch of main empties via minor sphincter into duodenum

Vascular supply

Gastroduodenal artery supples head (seen anterolateral aspect of head)

Splenic artery and SMA supply body and tail

Sonographic appearance of the adult pancreas

Adult pancreas normally echogenic liver, isoechoic to the spleen

Sonographic appearance of the pediatric pancreas

Pediatric pancreas normally can be hypoechoic to liver

Sonographic appearance of the main pancreatic duct

Main pancreatic duct less than or equal to 2mm

May be see perpendicular to sound beam at level of body

-Color can be used to confirm its not the the splenic artery

In transverse pancreas head:

GDA: anterolateral aspect

CBD: posterolateral

Anatomical relationships:

-IVC

Posterior to head

Anatomical relationships

-Duodenum

Lateral to head

Anatomical relationships

-Portal confluence (or SMV)

Medial to head/ anterior to uncinate process/ posterior to neck

Anatomical relationships

-Splenic vein

Posterior to body/tail

Anatomical relationships

-Splenic artery

Superior to body/tail

Anatomical relationships

-SMA

Anterior to aorta/ posterior to pancreas body and splenic vein

Anatomical relationships

-left renal vein

Posterior to SMA

Anterior to aorta

Anatomical relationships

-right renal artery

Posterior to IVC

Variants

Divisum

Annular

Divisum

Most common

Shortened main pancreatic duct, forces accessory duct to become primary drainage= increases risk dilated duct and pancreatitis

Annular

pancreas head wraps around duodenum like a ring, may lead to bowel obstruction

What is the most common cause of acute pancreatitis

Choledocholithiasis (gallstones)

Causes of acute pancreatitis

Choledocholithiasis (gallstones)

Alcoholism

Trauma

How is the inflammation caused in acute pancreatitis?

• The pancreas makes digestive enzymes (like amylase and lipase) that help break down food.

• Normally, these enzymes are stored in an inactive form inside the pancreas and are only activated once they reach the small intestine.

• In acute pancreatitis, something (like a gallstone or alcohol) disrupts the normal flow of these enzymes.

• As a result, the enzymes may become activated too early—inside the pancreas instead of the intestine.

• These active enzymes start to "digest" the pancreas itself, damaging its tissue.

• This damage leads to inflammation

Labs associated with acute pancreatitis

-Amylase rises first

-Lipase within 72 hours but more specific for pancreatitis

Most common vasculature complications of acute pancreatitis

-Splenic vein thrombosis

-Splenic artery pseudoaneurysm

Clinical findings of acute pancreatitis

Acute -itis symptoms:

-Fever

-Pain

-Leuko

-Elevated amylase and lipase

-Elevated biliary obstructive labs if caused by stone

Sonographic appearance of acute pancreatitis

Initial= normal

If findings= hypoechoic, enlarged, phlegmon (perioancreatic fluid), pseudocyst (most common in lesser sac), possible ductal dilation

Phlegmon vs pseudocyst

Phlegmon: peripancreatic fluid

-rim of fluid surrounding pancreas, not encapsulated and only with acute

Pseudocyst: encapsulated fluid collection most commonly found in lesser sac

-Can be with acute and chronic

Chronic pancreatitis

Repeated bouts= damaged organ

-Not the active infection

Most commonly found in cases of pancreatitis caused by alcohol abuse

Clinical findings of chronic pancreatitis

Jaundice

Abnormal labs

Weight loss

Sonographic appearance of chronic pancreatitis

heterogeneous

Hyperechoic with calcifications

Possible pseudocyst

Possible ductal dilatation

Pancreatic adenocarcinoma

AKA ductal adenocarcinoma

Most common primary pancreatic cancer

Most common location is the head= related to biliary dilatation

Treatment for pancreatic adenocarcinoma

Whipple procedure: Removes pancreatic head, duodenum, gallbladder, and bile duct

Courvoisier gallbladder

This refers to an enlarged, palpable gallbladder that can be felt during an exam, often due to a mass in the pancreatic head blocking bile flow. This is considered a classic sign of pancreatic cancer.

-Associated with painless jaundice

Clinical findings of pancreatic adenocarcinoma

Weight loss, abnormal Labs= ALP (Alkaline Phosphatase), conjugated bilirubin

Sonographic appearance of pancreatic adenocarcinoma

Hypoechoic mass

Dilated ducts

Possible enlarged gallbladder

Pancreatic cystadenomas and cystadenocarcinoma

These are cystic (fluid-filled) tumors in the pancreas, and they come in two types: Serous and mucinous

Most commonly in body and tail

Serous

(Microcystic)

-Benign

Mucinous

(Macrocystic)

-May be malignant

Clinical findings of pancreatic cystadenomas and cystadenocarcinoma

Weight loss

Pain

Sonographic appearance of pancreatic cystadenomas and cystadenocarcinoma

Cystic or multilocular cystic mass

Islet cell tumor

These are endocrine tumors of the pancreas, meaning they originate from hormone-producing cells (the Islets of Langerhans).

• Most are benign, but since they produce hormones, they can cause symptoms due to hormonal imbalances.

Types of islet cell tumor

Insulinoma

Gastrinoma

Insulinoma

More common out of the two

• Causes hypoglycemia (low blood sugar) because too much insulin is being produced.

Gastrinoma

• Produces excess gastrin, a hormone that increases stomach acid production.

• This can lead to Zollinger-Ellison syndrome, which causes peptic ulcers or stomach ulcers due to too much stomach acid

Pancreatic cysts

Benign

Associated with other conditions:

-von Hippel-Lindau or renal cystic diseases

Pancreatic transplant

• Pancreatic transplants are often done for people with severe Type 1 Diabetes (T1DM), where the endocrine function of the pancreas (insulin production) has failed.

Types of Exocrine Drainage in Pancreatic Transplants

-exocrine enteric drainage

-exocrine bladder drainage

Signs of rejection for a pancreas transplant

Increase RI in artery

Exocrine enteric drainage

Most common

Donor duodenum to recipient jejunum RUQ

Exocrine bladder drainage

The donor pancreas is connected to the urinary bladder instead of the small intestine. This is a less common technique.