Chapter 6 Goals Page 187 Students will be able to: Define new suffixes & use them to form terms related to the digestive system. List & explain laboratory tests, clinical procedures, & abbreviations relevant to the digestive system Apply your new knowledge to understanding medical terms in their proper context, such as in medical reports & records & in personal vignettes.

Additional Suffixes & Digestive System Terminology Chapter 6 Pages 187 – 214

Laboratory Tests & Clinical Procedures Page 193 Laboratory Tests & Clinical Procedures Laboratory Tests Amylase & Lipase Tests Tests for the levels of amylase & lipases enzymes in the blood Increase levels are associated with pancreatitis Stool Culture Test for microorganisms present in feces. Feces are placed in a growth medium & examined microscopically

Laboratory Tests & Clinical Procedures: Cont. Page 193 Laboratory Tests & Clinical Procedures: Cont. Liver Function Tests (LFTs) Tests for the presence of enzymes & bilirubin in blood LFTs are performed on blood serum (clear fluid that remains after blood has clotted). Examples of LFTs are tests for ALT (alanine transaminase) & AST (aspartate transaminase). ALT & AST are enzymes present in many tissues. Levels are elevated in the serum of patients with liver disease. High ALT & AST levels indicated damage to liver cells (as in hepatitis)

Laboratory Tests & Clinical Procedures: Cont. Page 193 Laboratory Tests & Clinical Procedures: Cont. Liver Function Tests (LFTs) Alkaline phosphatase (alk phos) is another enzyme that may be elevated in patients with liver, bone, & other diseases. Serum bilirubin levels are elevated in patients with liver disease & jaundice. A direct bilirubin test measures conjugated bilirubin. High levels indicate liver disease or biliary obstruction. An indirect bilirubin test measures unconjugated bilirubin. Increased levels suggest excessive hemolysis, as may occur in a newborn.

Laboratory Tests & Clinical Procedures: Cont. Page 193 Laboratory Tests & Clinical Procedures: Cont. Stool Guaiac Test or Hemoccult Test Test to detect occult (hidden) blood in feces This is an important screening test for colon cancer. Guaiac is a chemical from the wood of trees. When added to a stool sample, it reacts with any blood present in the feces.

Laboratory Tests & Clinical Procedures: Cont. Page 194 Laboratory Tests & Clinical Procedures: Cont. Clinical Procedures X-Ray Tests X-ray imagining is used in many ways to detect pathologic conditions. In dental practice, x-ray images are commonly use to locate cavities (caries). Many of the x-ray tests listed here use a contrast medium (substance that x-rays cannot penetrate) to visualize a specific area of the digestive system. The contrast, because of its increased density relative to body tissue, allows organs & parts to be distinguished from one another on the film or screen.

Laboratory Tests & Clinical Procedures: Cont. Page 194 Laboratory Tests & Clinical Procedures: Cont. Lower Gastrointestinal Series (barium enema) X-ray image of the colon & rectum obtained after injection of barium into the rectum Radiologists inject barium (a contrast medium) by enema into the rectum

Laboratory Tests & Clinical Procedures: Cont. Page 194 Laboratory Tests & Clinical Procedures: Cont. Upper Gastrointestinal Series X-ray image of the esophagus, stomach, & small intestine obtained after administering barium by mouth Often performed immediately after an upper gastrointestinal series, a small bowel follow-through study shows sequential x-ray pictures of the small intestine as barium passes through. A barium swallow is a study of the esophagus.

Laboratory Tests & Clinical Procedures: Cont. Page 194 Laboratory Tests & Clinical Procedures: Cont. Cholangiography X-ray examination of the biliary system performed after injection of contrast into the bile ducts. In percutaneous transheptic cholangiography, the contrast medium is injected using a needle placed through the abdominal wall into the biliary vessels of the liver. In endoscopic retrograde cholangiopancreatography (ERCP) contrast medium is administered through an oral catheter (tube) & then passes through the esophagus, stomach, & duodenum & into bile ducts. This procedure helps diagnose problems involving the bile ducts, gallbladder, & pancreas.

Laboratory Tests & Clinical Procedures: Cont. Page 195 Laboratory Tests & Clinical Procedures: Cont. computed tomography (CT) A series of x-ray images are taken in multiple views (especially cross section) A CT scan uses a circular array of x-ray beams to produce the cross-sectional image based on difference in tissue densities. Use of contrast material allows visualization of organs & blood vessels & highlights differences in blood flow between normal & disease tissues. Tomography produces a series of x-ray pictures showing multiple views of an organ. An earlier name for a CT scan is "CAT scan" (computerized axial tomography scan).

Laboratory Tests & Clinical Procedures: Cont. Page 196 Laboratory Tests & Clinical Procedures: Cont. Ultrasound Examinations abdominal ultrasonography Sound waves beamed into the abdomen produce an image of abdominal viscera Ultrasonography is especially useful for examination of fluid-filled structures such as the gallbladder

Laboratory Tests & Clinical Procedures: Cont. Page 196 Laboratory Tests & Clinical Procedures: Cont. endoscopic ultrasonography (EUS) Use of an endoscope combined with ultrasound to examine the organs of the gastrointestinal tract. An endoscope is inserted through the mouth or rectum, & ultrasound images are obtained. This test is often used in assessing esophageal, pancreatic, & rectal cancer.

Laboratory Tests & Clinical Procedures: Cont. Page 196 Laboratory Tests & Clinical Procedures: Cont. Magnetic Resonance Imaging magnetic resonance imaging (MRI) Magnetic waves produce images of organs & tissues in all three planes of the body This technique does not use x-rays. It detects subtle difference in tissue composition, water content, & blood vessel density & can show sites of trauma, infection, or cancer. CT scanning would not have shown lesions as clearly as MRI

Laboratory Tests & Clinical Procedures: Cont. Page 197 Laboratory Tests & Clinical Procedures: Cont. Nuclear Medicine Test HIDA Scan Radioactive imaging procedure that tracks the production & flow of bile from the liver & gallbladder to the intestine HIDA stands for hepatobiliary iminodiacetic acid. Cholescintigraphy is another name for this test, which determines if the gallbladder is functioning properly.

Laboratory Tests & Clinical Procedures: Cont. Page 197 Laboratory Tests & Clinical Procedures: Cont. Other Procedures gastric bypass or bariatric surgery Reducing the size of the stomach & diverting food to the jejunum (gastrojejunostomy). This is bariatric surgery for severe obesity. The Roux-en-Y gastric bypass procedure reduces the size of the stomach to a volume of 2 tablespoons & bypasses much of the small intestine. The name Roux-en-Y comes from the surgeon who first described it (Cesar Roux) & anastomosis of the duodenum & jejunum, which looks like the letter Y.

Laboratory Tests & Clinical Procedures: Cont. Page 198 Laboratory Tests & Clinical Procedures: Cont. gastrointestinal endoscopy Visual examination of the gastrointestinal tract using an endoscope. A physician places a flexible fiberoptic tube through the mouth or the anus to view parts of the gastrointestinal tract. Examples are esophagogastroduodenoscopy (EGD), colonoscopy, sigmoidoscopy, proctoscopy, & anoscopy. Virtual colonscopy (CT colongraphy) combines CT scanning & computer technology to enable physicians to examine the entire length of the colon by x-ray imaging in just minutes. Patients with abnormal findings require conventional colonoscopy afterward for further assessment or treatment, such as with biopsy or polypectomy.

Laboratory Tests & Clinical Procedures: Cont. Page 199 Laboratory Tests & Clinical Procedures: Cont. Laparoscopy Visual (endoscopic) examination of the abdomen with a laparoscope inserted through small incisions in the abdomen. Laparoscopic cholecystectomy & laparoscopic appendectomy are performed by gastrointestinal & general surgeons.

Laboratory Tests & Clinical Procedures: Cont. Page 199 Laboratory Tests & Clinical Procedures: Cont. Liver Biopsy Removal of liver tissue for microscopic examination A physician inserts a needle through the skin to remove a small piece of tissue for microscopic examination. The average sample is less than 1 inch long. The procedure helps doctors diagnose cirrhosis, chronic hepatitis, & tumors of the liver.

Laboratory Tests & Clinical Procedures: Cont. Page 199 Laboratory Tests & Clinical Procedures: Cont. Nasogastric Intubation Insertion of a tube through the nose into the stomach Physicians use a nasogastric (NG) tube to remove fluid postoperatively & to obtain gastric or intestinal contents for analysis

Laboratory Tests & Clinical Procedures: Cont. Page 199 Laboratory Tests & Clinical Procedures: Cont. Paracentesis (abdominocentesis) Surgical puncture to remove fluid from the abdomen This procedure is necessary to drain fluid (accumulated in ascites) from the peritoneal (abdominal) cavity