Lesson 4 Pancreas part 1 AM.pptx

Lesson 4 Pancreas Sonography: Introduction to Normal Structure and Function 5th edition by Reva Curry, Marilyn Prince Chapter 14 Outline of Today’s Class Pancreas Basic anatomy and function Clinical Indications...

Lesson 4 Pancreas Sonography: Introduction to Normal Structure and Function 5th edition by Reva Curry, Marilyn Prince Chapter 14 Outline of Today’s Class Pancreas Basic anatomy and function Clinical Indications Sonographic Landmarks Normal Sonographic Parameters How we scan the Pancreas?  Anatomy, Function, Vascularity, Sonographic Parameters, Appearance and Landmarks Pancreas PANCREAS: It was there all along and I didn’t notice Anatomy of Pancreas Lies in the midline (What Region?) Composed of exocrine and endocrine tissue Most of the tissue is exocrine 2 Functions Exocrine Digestion Secretes pancreatic juice Break up fat, carbohydrates and protein into smaller molecules Endocrine Hormones such as Glucagon and insulin Maintain sugar and salt balance Exocrine Acini cells 90% performs exocrine functions Small grape like structures with endocrine tissue in between Pancreatic juices composed of: Amylase, lipase, trypsin, chymotrypsin, carboxypepidase, nucleases, sodium bicarbonate  Functions of the Pancreas Exocrine 90% Components of Pancreatic Acts on Juice Enzyme Amylase Carbohydrates Lipase Fats Trypsin, chymotrypsin, Proteins carboxypeptidase Nucleases Nucleic acids Sodium bicarbonate Hydrochloric acid 8 Digestion Duct of Wirsung (Main panc duct) and Duct of Santorini (smaller accessory duct) Pancreatic juice collects in ducts of Wirsung then moves into the duodenum through the ampulla of Vater The sphincter of Oddi relaxes to allow the passage of the juices. Endocrine Function Islets of Langerhans Consist of alpha, beta and delta cells Secrete hormones directly into blood stream  Functions of the Pancreas Endocrine 10% Type of Cell Hormone Action Beta Insulin Glucose→Glycogen Alpha Glucagon Glycogen→Glucose Delta Somatostatin Alpha/beta inhibitor Gamma Pancreatic Related to blood sugar polypeptide regulation Epsilon Ghrelin Related to blood sugar regulation 13 Vascularity Arterial: Pancreaticoduodenal Artery (branches of the Gastroduodenal artery (GDA) Supply head and part of the duodenum Branches of Splenic Artery Supply Body and tail Courses on the superior edge, tortuous Before it enters the spleen Hagen-Ansert, S. ( 2018) Textbook of Diagnostic Sonography (8th ed.). Elsevier Health Sciences (US). https://pageburstls.elsevier.com/books/9780323353755 Vascularity Venous Tributaries of: SMV Splenic V  http://www.youtube.com/watch?v=1l2GTGEw ZOY&feature=related Location and parts Pancreas lies in the Retroperitoneum in the Epigastric region Three key Regions: Head  Uncinate process considered part of head Body Tail 4th Region known as the Neck Atlas of Human Anatomy Frank Netter PP. 360 – 363 Look at images and try to see which part is more superior/ inferior, posterior/ anterior and rt/lt Specific Locations of parts Head More inferior (caudal) to the body and tail  Neck and Body  more superficial than head and tail  Tail  More superior and posterior direction towards spleen Sonographic Parameters of Pancreas Varies widely in echogenicity, texture, shape and size Echogenicity- usually Isoechoic or hyperechoic to liver increases in echogenicity with age **Uncinate process can appear hypoechoic to the rest of the pancreas** Echotexture Homogenous (can have a mottled appearance) mottled - marked with spots of different colors : having blotches of two or more colors Is this pancreas Isoechoic or Hyperechoic to the liver? Mottled (like heterogeneous)  Size Varies, comparable btw sexes, decrease in size with age Head usually largest in dimension Neck smallest Body and tail slightly smaller than head  Shape Varies in shape Contour Usually smooth, occasionally see lobulated If increased in echogenicity with age can blend in with retroperitoneal fat makes it hard to tell true size or contour Size of the Adult Pancreas Total length of pancreas 12-18 cm Head 2-3 cm (AP diameter) Neck 1.5-2.5 cm (AP diameter) Body 2-3 cm (AP diameter) Tail 1-2 cm (AP diameter) 31 How do I find the Pancreas??? Useful landmarks to help you identify the parts of the Pancreas Landmarks for Head of Pancreas Gastroduodenal Artery (GDA) Anterior lateral aspect of pancreas head Second part of duodenum lies lateral to GDA Common Bile Duct (CBD) Posterior lateral aspect of head Inferior vena Cava posterior Less Helpful 3rd part of Duodenum inferior aspect Trans Pancreas Head in Curry Landmarks for the Neck and Uncinate process Anterior to the SMV and portosplenic confluence Landmarks for Body For the Pancreas Body “Superior mesenteric artery” easiest to find Splenic Vein Aorta Body is medial anterior to “Portosplenic confluence” Landmarks for the Tail Splenic vein lies posterior to the tail (Splenic artery is tortuous and travels adjacent to the splenic vein (seen in cross section)) Pancreas Ducts seen with ultrasound Sometimes we visualize these Main Pancreatic Duct or Duct of Wirsung dumps secretions into the duodenum via major papilla (ampula of Vater) Usually merges with common bile duct before entering the duodenum at the major papilla or ampula of Vater Ducts May seen on Ultrasound Main pancreatic duct or duct of Wirsung Accessory duct or duct of Santorini Size of Main pancreatic duct = 3mm or less Seen as linear structure in the pancreas body (remember seen echogenic walls if beam is 90 degrees) Anechoic (fluid filled) Hagen-Ansert, S. ( 2018) Textbook of Diagnostic Sonography (8th ed.). Elsevier Health Sciences (US). https://pageburstls.elsevier.com/books/9780323353755 Duct of Wirsung (main panc duct) Notice where CBD comes from then joins with Duct of Wirsung Scanning the Pancreas Typical Scan of Pancreas Pancreas routinely imaged in Abdominal ultrasound Fasting Patient 6 to 8hrs, use 3.5 to 5 MHz transducer Image in 2 planes Windows used Supine (most common) Right anterior oblique and left lateral decubitus Left coronal Image the long axis of the Pancreas in the Transverse Scanning the Pancreas Transverse images Demonstrate the head, body and tail (can see whole pancreas in transverse view) interrogation and image make sure to sweep superiorly to inferiorly Speared images and interrogations for head, body and tail Sagittal images Demonstrate head, body and tail (seen separately in this plane) Interrogate from the body to the head and out > back to the body and to the left out of the tail > back to the body