GI Anatomical Imaging Flashcards
Search Strategy for Abdomen
- what structures are you looking for in this area ( think organs, regions, ligaments)
Solid Organs: liver, spleen, pancreas, adrenal glands, kidneys
gallbladder/ bilary system
stomach, duodenum, rest of small bowel, colon
Fat planes abdominal wall, bone
lymph node chains: hepatogastric ligament, periportal region, mesentery
CT characteristics (8)
- pros
- cons
- uses Radiation
- Fast ( less than 5 min)
- Good overall look at SOLID organs, FAT PLANES
- Best spatial resolution
- Excellent for calcification
- Good for overall look of pelvic organs
- Iodine-based (IV) contrast
- limited detail
MRI characteristics
- Pros
- Cons
- No radiation
- not so fast ( > 20 mins)
- best tissue resolution
- not good for calcification
- excellent for pelvic organs (uterus, ovaries, prostate, seminal vesicles)
- Gadolinium -based IV contrast
Biliary Tree imaging
- diagnose problems of bile and pancreatic ducts
ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY (ERCP)
- modality of choice
- Xray is performed after visualization
Abdominal Aortic Vasculature (6)
- what imaging is best to view
- cons
- R & L gastric artery
- Proper hepatic artery
- Gastroduodenal artery
- Common hepatic artery
- Splenic artery
- Celiac trunk
- use Digital Subtraction arteriography
cons: invasive procedure
Ascites
- definition
- causes
- symptoms
- treatment
- accumulation of fluid in abdomen
most common cause: - liver cirrhosis
- salt and water retention
- heart failure
- cancer
Symptoms:
pain, discomfort, bloating
Tx: diuretics, therapeutic paracentesis
Mid-sagittal View
- Normal View
- useful in assessing SMA and nutcracker syndromes
Superior Mesenteric Artery Syndrome
- definition
- causes
- symptoms
- treatment
- digestive condition when 3rd part of duodenum is compressed between aorta and SMA
- short ligament of Treitz
Causes:
-partial or complete blockage of duodenum
Symptoms:
abdominal pain, fullness, nausea, vomiting, weight loss
TX: Sx may be needed if other treatment strategies do not work
Nutcracker Syndrome
- definition
- effects
compression of LEFT RENAL VEIN between SMA and aorta
- can lead to renal venous hypertension and disruption of thin veins in collecting system leading to hematuria
- SX may help to relieve compression
Hiatal Hernia
- describe
- symptoms
- bulge of stomach through esophageal hiatus into thorax
- due to age related changes to stomach and/or diaphragm
Symptoms:
- reflux
- sense of shortness of breath
Zenker’s Diverticulum
- describe/ location
- symptoms
- what imaging do you use?
- false diverticular formation in the esophageal wall adjacent to inferior pharyngeal constrictor and cricopharyngeus muscles
- due to uncoordinated swallowing and failure of cricpharyngeus m.
- in Killian’s triangle
- notorious for trapping food and causing severe halitosis
Symptoms
- dysphagia
- feelings of food being stuck in throat
- aspiration
- regurgitation hours after eating
- rarely a fluctuant mass is found in PE
Imaging
- use Fluoroscopic barium esophagography
- DO NOT use endoscopy
Ulcerative Colitis
- “lead” pipe appearance of long standing ulcerative colitis due to spasm of longitudinal muscles and/or irreversible fibrosis
- loss of haustral markings throughout the entire colon
Cholithiasis
- describe
- location/ tests
- gallbladder imaging
- formed by high concentrations of cholesterol or bilirubin in bile and/or inefficient emptying of gallbladder
- gallbladder is not typically well-visualized on plain films (X ray) of the abdomen without use of a contrast media
Symptoms:
- gallstones
- RUQ pain=> radiate to shoulder
- Positive Murphy’s sign
- Procedure of choice for suspected cholithiasis is ultrasonography
Beak Sign of Arterial Dissection
- luminal dissection of vessel
- can be seen as wedge of hematoma at distal end of false lumen ( false lumen propagation is occuring)
- manifest as acute angle between dissection flap and outer wall
- may be filled with contrast-enhanced blood (high attenuation) or thrombus ( low attenuation)
Shatzki Ring
- narrowing of esophagus caused by a RING of mucosal tissue (which lines the esophagus) or muscular tissue
- can cause difficulty in passing liquids and food
Hirschsprung’s Disease
- absence of ganglionic plexus due to absence of migration of neural crest
- increase wall thickness due to hypertrophy in intestine proximal to aganglionic segment
- lack of peristalsis (colon fails to relax)
- abnormal colonic dilation or distension (megacolon)
- surgical removal of constricted distal segment
Types of imaging modalities ( 7)1
- Xray
- barium swallow - Manometry
- Ultrasound
- ERCP
- Arteriography
- CT
- IV vs Oral Contrast
- IV contrast cleared by kidneys - MRI
X-rays
- characteristics
- pros/cons
- most common diagnostic imaging techniques
- relatively low cost
- low level of radiation (good for pregnant pts)
- usually first study preformed
Special Cases for X-rays (5)
- Fluoroscopic barium esophagography (aka Barium swallow)
- Barium enema
- ERCP
- Digital Subtraction angiography
- “KUB” XR: Kidney, Ureter, Bladder
- kidney stones
- certain types of gallstones
- blockages
Killian’s Triangle
- location
superior to cricopharyngeus m.
inferior to thyropharyngeus m.
Paraesophageal hiatal hernia
GEJ is unaffected
fundus of stomach is displaced
Sliding Hiatal hernia
GEJ is elevated
cardia of stomach is displaced
X ray: Barium enema
XR study used to diagnose conditions affecting the large colon
can help identify polyps or inflammatory bowel disease ( exm. ulcerative colitis)
Achalasia
- describe
- symptoms
- imaging
failure of LES to relax
symptoms: difficulty swallowing liquids and slids
can be infection (Chagas disease) or autoimmune
MANOMETRY
ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY (ERCP)
- describe
- risk factors
for biliary tree
a flexible tube is passed to 2nd portion of duodenum and contrast is injected into ampulla of Vater
- both a diagnostic and treatment modality
- for gallstone obstructions
- can perform stenting to improve drainage
- has 5-10% risk of causing iatrogenic pancreatitis
Digital subtraction angiography
helps identify compromised arterial flow
a catheter is inserted and dye is injected to provide contrast visualization of arterial supply to particular region
help identify compromised arterial flow
Ultrasonography
- great for which disease
uses high frequency sound waves to produce images of internal structures
good for diagnosising CHOLELITHIASIS
