Git Radiology and Imaging
Transcript of Git Radiology and Imaging
Page 1 of 4
MEDICINE
GIT RADIOLOGY AND IMAGINGLecturer: Dr. Renato M. Carlos| Date: 09-25-09 Transcriber(s): Kat S.
OUTLINEI. IntroductionII. Imaging Modalities
A. Plain Abdominal RadiographB. Contrast examinations
1. Barium swallow / esophagogram2. UGIS3. SBS4. Barium enema
C. UltrasoundD. CT ScanE. MRIF. ERCP
T tube CholangiogramIOC
III. Interventional radiologyA. Angiogram and embolizationB. Abscess drainageC. CT guide biopsy
INTRODUCTION
DENSITIES
AIR FAT WATER
SOFT TISSUE
S
BONE
2 Basic: 1. Black – radiolucent (air and fat)2. White – radioopaque (include bones, metals and
contrast medium)Intermediate density – gray color – water and soft tissues or organ structures.
Intestines- contain air.
IMAGING MODALITIESA. PLAIN ABDOMINAL RADIOGRAPH- Used to show calculi, calcifications, stones,
tumors- Take note of the pattern of calcifications. If its
toothlike – think of teratoma or cyst; vascular calcification – hemangiomas that appears as ring-like
Indications:1. Abdominal pain2. Abdominal distention – obstruction, ileus, atresia3. Vomiting4. Diarrhea5. Trauma – intraabdominal bleeding and ruptured
viscous → pneumoperitoneumThings to look at
1. Intestinal Gas Pattern2. Osseous Structures3. Abnormal Calcifications4. Abnormal Soft Tissue Densities5. Renal Shadow6. Psoas Shadow
a. b.
Pneumoperitoneum – in ruptured viscous. Air escapes into the peritoneal cavity, Double wall sign – translucent inner wall (mucosa) and outer wall (serosa). Boarder of the liver and diaphragm is also seen, as air insinuates in between. Rigler’s sign – upright position,air goes up, inner and outer wall of the stomach is seen.
B. CONTRAST EXAMINATIONS1. Barrium swallow / esophagogramBarium sulfate- contrast medium used, an inert substance, radioopaqueIndications: - esophageal motility disorders - atresia and tracheoesophageal fistula - duplication - esophageal diverticula - foreign bodies - esophageal perforation - hiatal hernia - esophagitis - rings, webs and strictures - esophageal varices - esophageal tumors
2. Upper GI series- px on NPO, ingest barrium and effervescent tablet
Indications◦ Hematemesis ◦ Melena ◦ Hernia◦ subacute or chronic nausea and vomiting◦ palpable mass in the upper abdomen
(Symptoms related to peptic ulcer disease or lesions involving the stomach and duodenum)
Page 2 of 4
Enlarging mass in the lower neck.
Diverticulosis - outpouching
a. Duodenal atresia – double bubble sign, shows an enlarged stomach and proximal duodenal distention, absence of distal gas (colonic gas)b. Jejunal atresia – triple bubble sign.
Calcifications and psoas shadow - psoas muscles bounded by fat thus appears translucent and is enlarged in the presence of tumors and abscesses. Kidneys lie along the lumbar area and is also bounded by fat -
Air fluid levels – step ladder sign- Distended jejunum appears as stack of coins, mucosal folds are more adherent to each other-ileum when distended mucosal folds are effaced-Obstruction is more distal somewhere in the ileum
Achalasia – severe narrowing in the gastroesophageal junction, proximal is dilated and distal is constricted -in advance cases esophagus may appear sigmoid- terminal part shows a beak-like narrowing representing an
Peptic Ulcer -seen outpouching or mound which corresponds to the edematous base around the ulceration, it has to be big for it to be seen in UGIS.– not anymore used for its diagnosis
3. Small Bowel Series (SBS)Indications
a. Inflammatory, neoplastic or infectious diseases which result in mucosal changes or obstruction of the small bowels.
4. Barium enema- Used to study the colon
- Px on NPO, laxative given to cleanse to bowel, catheter inserted into the anus, barium is injected and pushed with air.
Indicationsa. hematochezia b. rectal bleedingc. change in stool caliberd. constipation e. weight lossf. severe anemia
(Symptoms related to Colon Cancer or Inflammatory Bowel Disease)
C. ULTRASOUNDIndications
◦ Evaluation of solid organs such as the liver, pancreas, spleen, kidneys and fluid-filled structures such as the gallbladder and urinary bladder
◦ Ability to characterize lesions as solid, cystic or complex
◦ Of value in evaluating nonpalpable, intraabdominal and retroperitoneal masses
◦ Small amount of fluid collections in the peritoneal space are also easily assessed.
- Any enlargement of the structures suspect tumor, about >2.5 cm
- Gall bladder- pear shaped, wall measures 8mm, if there’s thickening – cholecystitis
- Fluids such as Bile appears dark, while calcifications or stones appears white (hyperechoic)
Page 3 of 4
Widening of C loop on SBS-doudenal loop in relation with the pancreas - Enlarging pancreatic mass
Double contrast exam – barium is radio opaque and effervescent is translucent. Take note of the mucosal patterns of the small intestine, more adherent unlike the haustra of the
String sign-hypertrophic pyloric stenosis- narrowing of the lumen of the pylorus (but is now directly dx by the use of UTS)
This shows the distribution of the small bowel. Take note of the differences of the valvulated patterns, more prominent in the jejunum than in ileum-transit time of the
Lymphoma-segmentation and distortion of the mucosal folds, characteristic finding of malabsorption syndrome
Diverticulosis – multiple diverticles or outpouchings taking up the medium. Causes severe bleeding, can become infected-diverticulitis- when ruptured produces intramural abscess or localized peritonitis.Also diagnosed with CT scan
Haustral patterns is 2-3cm apartAppendix is 2-3 haustras apart beyond the ileocecal valve that is like a lip.Tumors cause narrowing of the lumen
Colon cancer-apple core deformity-tumors are usually circumferential, produce narrowing of the lumen- Adenocarcinoma
Colitis-thumbprinting
-inflammation, infection or ischemia
Gall bladder: bile is dark, inside is multiple small echogenic foci. Due to calcifiactions/stones, sound waves can’t penetrate through it and produces distal acoustic shadowing – Cholelithiasis
h
D. CT SCANIndications
a. A powerful imaging technique for evaluating the abdominal walls, intraperitoneal and retroperitoneal spaces, all organ systems, fascial planes and potential spaces
b. May be used to evaluate the entire abdomen for masses and their extension into adjacent structures.
c. Can also differentiate between solid and cystic masses, exudates from transudates, and can demonstrate calcifications within masses
- Given contrast medium to enhanced structures- vessels appear white, fat appear dark.
Advantage over MRI: -Used in general abdominal cases-Can detect calcifications, MRI does not- it takes about 10 sec to scan the entire abdomen, while MRI takes about 30-45min
-In Sigmoid Ca – advantage of CT over barium enema is that your able to identify if there’s serosal involvement or any involvement outside the colon which is important in staging.
Multi-detectional CT scan – able to attain different planes or sections-virtual colonography - able to show the mucosal linings, can able to detect polypoid lesion and tumor
E. MRIAdvantages over CT: can evaluate pancreas, adrenals and chemical structures. No use of X-ray
F. ERCP(Endoscopic Retrograde Cholangiopancreatography)
Cholangiography – used to study biliary treeIndications/Method of Examination
◦ can be used to evaluate the biliary tree to detect common bile duct stones, inflammatory or neoplastic duct anomalies
◦ During ERCP, sphincterotomy, biopsy, stone extraction, and mucosal brushings can be done
◦ IOC may be used to visualize nonpalpable stones during surgery
◦ T-tube cholangiogram is used to detect retained stones after surgery
Normal T-tube Normal ERCP CBD stone
MRCP advantages over ERCP(a) is noninvasive (b) is cheaper (c) uses no radiation(d) requires no anesthesia(e) is less operator dependent(f) allows better visualization of ducts proximal to an obstruction(g) when combined with conventional T1- and T2-weighted sequences, allows detection of extraductal disease.
IOCOral Cholecystogram – showing multiple gall stones
IV. INTERVENTIONAL RADIOLOGY
A. Visceral Angiogram and embolizationIndications
- evaluation and treatment of vascular diseases- presurgical evaluation of lesions- Embolization: Endovascular treatment of specific diseases, e.g. bleeding control, tumor chemoembolization, pre-operative devascularization…
Technique:- Patient positioning, sterilization, draping- Introduction of Needle, Guidewire, Catheter, into Femoral Artery
Normal hepatic Hepatoma on angiogram Angiogram
B. Percutaneous Abscess/Fluid DrainageIndications
- Diagnostic sampling for Laboratory Analysis- Therapeutic management, removal of fluid for palliative or therapeutic purposes
C. CT-Guided BiopsyIndications
- Tissue diagnosis of disease- Aspiration for microbiologic/cytologic studies
Advantages vs. Surgical Biopsy1. management planning is immediate, therapy
may be initiated without waiting for the incision to heal
2. minimal trauma, to normal as well as neoplastic tissue, decreasing the risk of tumor dissemination
Page 4 of 4
Acute cholecystitis with lithiasisthickened gall bladder wall with pericholecystic fluid
- Acoustic shadowing
impacted stone at the gall bladder neck
HEPATORENAL SPLENORENAL
FAST (Focused Abdominal Sonography for Trauma)
Objective:Detection of free fluid (leaky fluid / minimal fluid) secondary to injury of the abdominal organs
3. risks of surgery and general anesthesia are avoided -done under local anesthesia
4. failure to obtain a diagnostic specimen does not preclude a surgical biopsy
PTBD(Percutaneous transhepatic biliary drainage)
- used when surgical intervention and ERCP to place a stent to bypass bile obstruction fails.
- under UTS and colonoscopy guidance, needle is inserted into the biliary system and tube is placed from the hepatic duct to the duodenum
- it does not cure the site of obstruction but it only drains the bile that is retained from obstruction
REFERENCE1. Lecture ppt and recording2. Wala masyado sa Harrisons
SHOUTOUTS! ^_^Thanks to Gail for the recording and kay Grace S. thank you na rin sa effort to send it, to Angel for the Harrison’s and jollibee breakfast.. To Alvin for the powerpoint.. And we must not forget to thank God for keeping us alive…continue to pray for our safety in all the calamities that may come..Goodluck to all of us.. esp sa exams, sana maging “physically, mentally, and emotionally ready tayo” (-Carlo Sancha) Hope you enjoyed our early sembreak.. hehe!
KEY POINTS1– Plain Abdominal Radiograph – shows calcifications. Stones and tumor2. Patterns of calcification: Toothlike – teratoma or cyst; Ring-like - hemangiomas3. Psoas shadow and renal shadow – bounded by fat thus appears translucent4. in small bowel obstruction/ atresia – absence of colonic or distal gas Duodenal atresia – double bubble sign; Jejunal atresia – triple bubble sign; Step ladder sign – air fluid levels5. Pneumoperitoneum: Double wall sign, Rigler’s sign6. Achalasia – shows beak-like in barium swalow7. Upper GI series: Double contrast exam Pancreatic mass – widening of C loop (duodenal loop) Hypertrophic pyloric stenosis – String sign8. Lymphoma-segmentation and distortion of the mucosal folds, characteristic finding of malabsorption syndrome9. Diverticulosis – multiple diverticles or outpouchings10. Colon cancer (adenoCa) -apple core deformity11. Colitis -thumbprinting12. Cholelithiasis - multiple small echogenic foci, calcifiactions/stones, distal acoustic shadowing; if with gall bladder wall thickening - cholecystitis13. FAST – detects free fluid14. T-tube cholangiogram is used to detect retained stones after surgery15. MRCP advantages over ERCP- allows detection of extraductal disease.
Page 5 of 4