DiagnosticTestsGastrointestinalTract.pptx

Radiological & Endoscopic investigations of gastrointestinal tract

1. DIAGNOSTIC TESTS FOR GASTROINTESTINAL DISORDERS

2. CONTENTS Physical Evaluation Lab Tests Endoscopic procedures Imaging Tests (Radiological Investigations)

3. Endoscopic procedures Endoscopy is a procedure that allows a doctor to view the inside of a person's body. Doctors use it to diagnose diseases in the following parts of the body : Esophagus, Stomach, Colon, Ears, Nose, Throat, Heart, Urinary tract, Joints, Abdomen. During an endoscopy, the doctor inserts a tool called an endoscope into a person’s body. Most endoscopes are thin tubes with a powerful light and tiny camera at the end. The endoscope's length and flexibility depend on the part of the body the doctor needs to see. For example, a straight endoscope helps a doctor look at joints, whereas a flexible one helps a doctor view the inside of the colon.

4. Types of Endoscopic procedures: Colonoscopy Used to view the whole length of the large intestine (colon). It can help to find abnormal growths, inflamed tissue, ulcers, and bleeding. A colonoscope is put into the rectum and moved up into the colon. A colonoscope is a long, flexible tube with a light on it that allows the healthcare provider to see the lining of the colon and remove tissue for further study (biopsy), if needed. A virtual colonoscopy is available that uses CT imaging to look at the colon. Fig: Colonoscopy

5. 2 . Esophagogastroduodenoscopy (EGD or upper endoscopy) An EGD allows the physician to look inside the esophagus, stomach, and duodenum with an endoscope. This scope is guided into the mouth and throat and then into the esophagus, stomach, and duodenum. He or she can also insert instruments through the scope to remove a sample of tissue for biopsy or for surgical removal of a tissue mass. When an ultrasound probe is attached to a scope, an internal ultrasound can be done – process known as Endoscopic ultrasound (EUS). Fig: Esophagogastroduodenoscopy

6. 3 . Endoscopic retrograde cholangiopancreatography (ERCP) Allows to diagnose and treat problems in the liver, gallbladder, bile ducts, and pancreas. It combines X- ray and the use of an endoscope. The scope is guided through your mouth and throat and then through the esophagus, stomach, and duodenum. The physician can look at the inside of these organs and diagnose problems, if any. A tube is then passed through the scope and a dye substance is injected that allows the internal organs to appear on an X-ray. Fig: Endoscopic retrograde cholangiopancreatography

7. 4. Sigmoidoscopy A sigmoidoscopy is a diagnostic procedure that allows the physician to examine the inside of a portion of the large intestine, and is helpful in identifying the causes of diarrhea, abdominal pain, constipation, abnormal growths, and bleeding. A short, flexible, lighted tube, called a sigmoidoscope, is inserted into the intestine through the rectum. The scope blows air into the intestine to inflate it and make viewing the inside easier. A sigmoidoscopy is one type of test used to screen for colon and rectal cancers. Fig: Sigmoidoscopy

8. Imaging Tests Barium Study During this test, the patient eats a meal containing barium (a metallic, chalky liquid used to coat the inside of organs so that they will show up on an X- ray). This allows the radiologist to watch the stomach as it clear the meal. The amount of time it takes for the barium meal to be digested and leave the stomach gives the physician an idea of how well the stomach is working and helps to find emptying problems that may not show up on the liquid barium X- ray. Barium meal examination is usually performed to help diseases of GIT like constrictions, hernias, obstructions or masses in the esophagus or stomach, and inflammatory or other diseases of the intestines. A barium swallow test may be done to diagnose problems in the pharynx and esophagus, cancer of the head and neck, pharynx, or esophagus, hiatal hernia, etc. Fig: Barium beefsteak meal

9. Types of Barium Study Barium Swallow Barium Meal Barium Followthrough Barium Enema

10. Barium Swallow

11. Barium Meal

12. Barium Followthrough

13. Barium Enema

14. Barium Enema

15. 2. Colorectal transit study This test shows how well food moves through the colon. The patient swallows capsules containing small markers which are visible on X- ray. The patient follows a high-fiber diet during the course of the test. The movement of the markers through the colon is monitored with abdominal X- rays taken several times 3 to 7 days after the capsule is swallowed. This test is most often used in patients who are suffering from chronic constipation. Fig: Colorectal transit study

16. 3. Computed Tomography scan (CT scan) It is an imaging test that uses X- rays and a computer to make detailed images of the body. A CT scan shows details of the bones, muscles, fat, and organs. A computerized tomography (CT) scan combines a series of X- ray images taken from different angles around your body and uses computer processing to create cross- sectional images (slices) of the bones, blood vessels and soft tissues inside your body. CT scan images provide more- detailed information than plain X- rays do. A CT scan has many uses, but it's particularly well- suited to quickly examine people who may have internal injuries from car accidents or other types of trauma . It can be used to visualize nearly all parts of the body and is used to diagnose disease or injury as well as to plan medical, surgical or radiation treatment. Fig: CT scan

17. 4. Defecography Defecography is an X- ray of the anorectal area that evaluates completeness of stool elimination, identifies anorectal abnormalities, and evaluates rectal muscle contractions and relaxation. During the exam, the patient's rectum is filled with a soft paste that is the same consistency as stool. The patient then sits on a toilet positioned inside an X- ray machine, and squeezes and relaxes the anus to expel the solution. The radiologist studies the X- rays to determine if anorectal problems happened while the patient was emptying the paste from the rectum. The technique traditionally involves fluoroscopy and barium, but an analogous MRI technique has also been developed MRI defecography). This test is used to evaluate disorders of the lower bowel that are not diagnosed by tests such as colonoscopy or sigmoidoscopy. Fig: Defecography

18. 5 . Magnetic resonance imaging (MRI) MRI is a diagnostic test that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body. The patient lies on a bed that moves into the cylindrical MRI machine where it takes a series of pictures of the inside of the body using a magnetic field and radio waves and the computer enhances the pictures produced. The test is painless, and does not involve exposure to radiation. Because the MRI machine is like a tunnel, some people are claustrophobic or unable to hold still during the test to whom a sedative may be given to help them relax. Metal objects cannot be present in the MRI room, so people with pacemakers or metal clips or rods inside the body cannot have this test done. It can be used to diagnose tumors of the abdomen or pelvis. diseases of the liver, such as cirrhosis, and abnormalities of the bile ducts and pancreas. inflammatory bowel disease such as Crohn's disease and ulcerative colitis, etc. Fig: MRI of abdomen Fig: MRI machine

19. 6 . Magnetic resonance cholangiopancreatography (MRCP) The technique uses MRI to visualize the biliary and pancreatic ducts non-invasively. The machine uses radio waves and magnets to scan internal tissues and organs. This procedure can be used to determine whether gallstones are lodged in any of the ducts surrounding the gallbladder. Indications for the use of MRCP include – unsuccessful or contraindicated ERCP, patient preference for non- invasive imaging, patients considered to be at low risk of having pancreatic or biliary disease and those with a suspected neoplastic cause for pancreatic or biliary obstruction Fig: Magnetic resonance cholangiopancreatography

20. 7 . Radioisotope gastric- emptying scan During this test, the patient eats food containing a radioisotope, which is a slightly radioactive substance that will show up on a scan. The dosage of radiation from the radioisotope is very small and not harmful, but allows the radiologist to see the food in the stomach and how quickly it leaves the stomach, while the patient lies under a machine. A Gastric Emptying Study is a test to determine the time is takes a meal to move through a person's stomach (Gastric emptying time). The technique is used to diagnose gastroparesis, a condition in which the stomach's muscles don't work properly. Typically Tc- 99m sulphur colloid or Tc- 99m DTPA is the radioisotope used. Fig: Radioisotope gastric- emptying scan

21. 8 . Ultrasound Ultrasound is a diagnostic imaging technique that uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. They are used to view internal organs as they function, and to assess blood flow through various vessels. Gel is applied to the area of the body being studied, such as the abdomen, and a wand called a transducer is placed on the skin. The transducer sends sound waves into the body that bounce off organs and return to the ultrasound machine, producing an image on the monitor. Intestinal ultrasound is a safe and inexpensive method that allows visualization of the gastrointestinal tract and detection of abnormalities. - This examination involves the use of two different ultrasound transducers: a low-frequency convex probe and high-frequency linear probe. Fig: Ultrasound

22. 9 . Plain Abdominal Radiograph Though discussed at last ;actually ,it is the first radiological Investigation that is done. Though it is a simple investigation but can help diagnose a lot of GIT pathologies on its own. But Two important diagnostic importance is in two broad surgical emergencies Small & Large bowel Obstruction Hollow Viscus perforation

23. Bowel Obstruction Bowel Obstruction present with Multiple air fluid levels We earlier discussed about normal air fluid levels. There are certain specific signs that can diagnose peculiar conditions causing Bowel Obstruction.

24. Double bubble sign in Duodenal Atresia

25. Triple bubble Sign in Jejunal Atresia

26. Omega or Coffee Bean sign in Sigmoid Vulvulus

27. Hollow Viscus Perforation There Free gas below the diaphragm in Abdominal Xray in erect position. A few conditions that present with Free gas below the diaphragm are: Peptic Perforation Enteric Perforation (Typhoid) Caecal ,Large bowel Perforation Gun Shot/Stab injuries to Bowel.