1. RADIOLOY OF GIT (BLOCK)
OBJECTIVES
By the end of this lecture students will be able to
Know the radiological anatomy, of the esophagus,
stomach, appendix, colon, liver, biliary system, pancreas, spleen, inguinal region, and peritoneum.
Discuss the modalities available to image the GIT.
Discuss the limitation and appropriate indications of plane radiography in GIT
Know the clinical indication of contrast studies in GIT and biliary system.
Know radiological features of some common pathologies.

2. IMAGING MODALITIES
Plane x-rays. Fluoroscopy for the gut mainly Ultrasound Computerized Tomography (CT) Magnetic Resonance Imaging (MRI) Radioisotopes studies Angiography Most common use in GIT : planx-rays, Fluoroscopy Ultrasound : for detdect stone

3. Principles of Radiography
The underlying physical principles of conventional radiography involve
Emitting a stream of photons from x-ray source, strike body tissue.
Photons with varying amount of energy exit the patient body and fall on image receptor/film, thus produce an image

4. Radiological Anatomy
Plane Radiography. Normal: The routine projection is supine film; however erect film is taken in certain cases in particular, patients with suspicious of intestinal obstruction to check for air-fluid levels. AP: anterioposterior position most common In some cases we use lateral potion for esophagus

5. Supine

6. IMAGING MODALITIES
Image key = shades
White bone and calcification
Black air
Grey soft tissue

7. Esophagus
Esophagus is 25cm long. It has three parts Cervical Thoracic Abdominal Stomach is j shape. Cardia Fundus Body Pyloric canal and sphincter

8. Foreign body in esophagus

9. X-ray abdomen supine Normal gas pattern
Small intestine intestine
Stomach

10. SMALL VS LARGE BOWEL. SMALL INTESTINE LARGE INTESTINE
Comparatively short 1.5m
Four parts. Cecum, colon, rectum and anal canal.
Wider . 5cm diameter
Large bowel is peripheral.
Haustra are present.
No villi.
Circular fold absent.
Long 5-7m
Three parts. Duodenum, jejunum and ilium
Normal small bowel diameter is 3cm.
Small bowel is central in distribution.
Volvulae conniventes which are mucosal folds run almost the whole width.
Villi are present.
Haustra absent.

11. X-ray abdomen Erect position show fluid levels .
Supine film

12. Normal Large intestine

13. Fluoroscopy: It gives a real time images of internal structures
Fluoroscopy: It gives a real time images of internal structures. It consist of an x-ray source, fluorescent screen and between the two the patient is put

14. Contrast Studies. Barium swallow
AP view and LA view of the barium-coated pharynx and hypopharynx obtained during phonation demonstrates normal anatomy but also aspiration of barium into the larynx and trachea. Ulso for esophagus
Barium swallow
Indication:
Dysphagia
Pain
Obstruction
Foreign body

15. Normal anatomic narrowing of esophagus

16. Normal esophageal rings and dilatations
A ring at the junction of tubular and vestibular esophagus
B ring. At the squamous and columnar epithelial junction
Hiatus hernia demarcated by red arrow

17. Corkscrew esophagus
Tertiary contractions
Normal peristalsis

18. Barium meal Indications: Pain, obstruction Hematemesis Perforation
Anoraxia,weight loss

19. Barium meal follow through
Indications: Pain, obstruction, weight loss
Barium meal: for stomach and duodenum ( jejunum and terminal ileum )
The name for the substanc ethat use in EVERY barium test is berium sulfate

20. Barium enema for large intestine
Indications:
Melena, Pain, weight loss and obstruction
Normal
Abnormal (Narrowed due to diseaase)

21. Contrast study of biliary tree
Plane x-ray showing calcified gallbladder.
Porcelain gallbladder

22. Ultrasound

23. Ultrasound: we use sound waves to produce image.
Water appear dark, soft tissue appear grey and stone appear white

24. Liver
RT Kidney
Liver
Hepatic vein

25. US is good imaging technique for gallbladder stone
GB septation
Gall stones

26. Lower abdominal aorta at bifurcation
Pancreas

27. Liver cysts

28. Computerized Tomography (CT)
Consist of
x-ray source
Detectors
Computer.
It cut the body in to thin slices(Cross section)
Show anatomy in more detail

29. CT abdomen with out contrast

30. CT with contrast

32. CT images of pelvis

33. CT scan shows liver masses
Metastasis
Hemangioma
Hepatocellular carcinoma

34. Why CT is better than ultrasound and x-rays for abdomen.
CT is better because it shows cross sectional images and demonstrate soft tissues, bony structures and blood vessels at the same time, so provide better anatomical detail. Sound waves can not pass through bones and poorly pass through air.

35. Comparison of CT,Ultrasond and plane x-rays for gallbladder stone.
Both CT and ultrasound are excellent in detecting stones, but why we prefer ultrasound?
Because
No radiation
Inexpensive
Easily available