Diagnostic Radiology: Radiography Flashcards
Mammography
- Low dose X-ray
- High contrast
- High resolution
- Screening
- asymptomatic patient
- early detection of small breast cancers e.g. DCIS - Diagnostic
- symptomatic patient
- USG / clinical exam detected breast mass
2 views:
- Medial lateral oblique view: can see pectoralis muscle
- Craniocaudal view
- Compressed view
- Magnified view: further characterise lesion e.g. microcalcification
Sensitivity decrease in dense breast —> less sensitive in young patients
Intravenous urogram (IVU)
Demonstrate urinary tract for suspected urinary tract pathology
Use IV non-ionic contrast which are excreted in kidney to contrast urinary system
Common indications:
- Haematuria
- Loin pain
Preparation:
- Laxative (decrease faecal matter)
- Fast for 4 hours
- Hydration —> distend urinary collecting system
- Vascular access
- Compression band —> distend pelvocalyceal system for evaluation
Fluoroscopy
- Dynamic movie
- also use X-ray
Use:
- GI
- Biliary system
- Genitourinary system
- Interventional procedures
Contrast medium:
- Barium
- Water-soluble contrast medium
- Air (by effervescent granules)
GI tract fluoroscopy
Barium swallow: Hypopharynx, Esophagus
Barium meal: Stomach, Duodenum
- dyspepsia
- epigastric pain
- weight loss
- suspected stomach cancer
- suspected perforation of peptic ulcer
Barium follow-through: Small bowel
- delayed film for small bowel evaluation
- nasal catheter inserted at duodenal-jejunum junction, give contrast —> double contrast (barium, methylcellulose) —> better distension, patient discomfort
Barium enema: Large bowel
- contrast reach caecum 4-6 hours
- change in bowel habit
- pain
- mass
- blood in stool
- bowel obstruction
- air inflation through rectum —> double contrast
Patient preparation for barium study
- Fasting
- Bowel preparation
- enema
- low residual diet x 3 days
- klean prep - IV Buscopan
- decrease bowel peristalsis
- better distension
Barium complications
- Perforation
- peritoneal adhesions
- granulomata
—> Barium peritonitis - Aspiration
- relatively harmless
- physiotherapy
Biliary tract fluoroscopy
Cholangiogram:
- Percutaneous cholangiogram
- T-tube cholangiogram
Indications:
- Assess biliary status —> obstruction e.g. stone, tumour, extrinsic compression
- Assess post-op status —> any leakage
Contraindications:
- Biliary sepsis
Interventional procedures
- Central line insertion
- Percutaneous transhepatic biliary drainage (PTBD) —> relieve obstruction
- Angiography
- assessment of arterial / venous disease
- localisation of site of haemorrhage +/- embolisation
- intravascular injection of contrast
- preparation: Fasting + IV access + Clotting profile / platelet
Adverse reactions of Intravascular contrast medium (water-soluble)
Mild:
- sneezing
- nausea
Moderate:
- pruritis
- flush
- fever / chills
- increased / decreased BP
Severe:
- difficulty in breathing
- periorbital edema
- cardiac arrhythmia
- pulmonary edema
- death
Risk of radiological examination
- Risk from radiation
- Risk from contrast medium
- Risk due to technique
Radiation
- No known safe radiation dose
- Spontaneous genetic mutations and malignant diseases
- Reduce unnecessary examination
- Use alternative e.g. USG, MRI
- Shielding of organs
- Filtration of x-ray beam
- Control of irradiation + Recording of irradiation time
- Thermoluminescent dosimeter + Lead apron to protect staff
- Quality assurance
