Effective Utilization of Imaging John V. Roberts, M.D. Premier Radiology Abdominal Imaging
Safety Contrast and Radiation What to order Abdomen/Pelvis Brain/Spine Chest Musculoskeletal Ob/Gyn Head and Neck Vascular Breast Questions Overview
Pros and Cons Plain Film- Quick, low radiation, not very much motion artifact but not as sensitive or specific as CT CT- Quick, sensitive and specific, but radiation, motion artifact, cost MRI- very sensitive and specific for certain disease processes, but motion artifact, takes long time, cost US- not very expensive, no radiation but can get artifact, dependent on sonographer, requires some patient participation Nuclear Medicine- very sensitive and specific for certain disease processes but takes long time, some tests are very expensive (MIBG)
Safety IV Contrast CT contrast allergy- Overall incidence of 0.2-0.7%, Life threatening of 0.01-0.02% Highest risk is prior reaction to CONTRAST- 5 times increased risk Patients with slightly increased risk- other allergies (anaphylactic), asthma, cardiac Premedication- Elective- Prednisone 50mg orally 13 hrs, 7hrs, and 1hr before imaging and Benadryl 50mg 1 hr before Emergency- Solu-Medrol 40mg IV 4 hrs before and Benadryl 50 mg IV 1hour before Extravasation- Incidence of 0.1-0.9% Can cause localize swelling Extreme cases can cause compartment syndrome Treat by elevating extremity as well as hot and cold presses Radiation Immediate effects Delayed effects
Abdomen and Pelvis Plain Film- Good for foreign bodies, calcifications, free air (dependent view), obstruction CT Abd and pelvis- good for almost everything IV contrast- almost always, exception Renal stones With and without- adrenal masses, renal masses, and hematuria Oral contrast- helps especially in thin and pediatric patient If evaluating a renal/adrenal/pancreatic/liver mass then not needed MRI- good for evaluating masses especially liver and adrenal, rectal cancer and perianal fistulas, biliary system (MRCP) With and without except MRCP, adrenal, and rectal cancer Ultrasound- gallbladder, liver, aorta, renal Nuclear Medicine- HIDA, HIDA with Stimulation, GI bleed
Brain CT- good first study, almost always without Trauma, headaches, tumors, confusion With contrast is rarely used, usually if without is positive, need a CT without if you order with MRI- Same indications as CT, more sensitive than CT Order with and without if concerned about neoplasm, infection, and demyelinating disease
Spine Plain film- good starting point, can see compression fractures, facet arthropathy, subluxation and disk space narrowing CT- usually without, good for acute trauma, congenital malformations, or postsurgical hardware MRI- great for degenerative disk disease, cord compression, and aging fractures With and without for infection, tumor, postsurgical or demyelinating process Nuclear medicine- bone scan can be used for fractures of vertebral body and neoplasms
Chest Plain Film: Quick, good first study CT with contrast- contrast helps evaluating trauma, mediastinal and hilar adenopathy, and vascular lesions CT without- can be used to evaluate lung and plural pathology CTA- PE or aorta- two different phases of contrast, coronary arteries MRI and US- Very limited role Nuclear medicine- V/Q scans
Musculoskeletal Plain Film: good first study, trauma, arthritis, dislocation CT- usually without contrast- trauma, fracture in osteoporosis, post op Can order with contrast if suspect soft tissue process (abscess) MRI Joints- usually without or intraarticular contrast Osteomyelitis and occult fractures- without Pediatric osteomyelitis, tumors, myositis, abscess- with and without Nuclear medicine- bone scan good for metastatic disease, fracture, arthritis, osteomyelitis (3 phase) Ultrasound- can be used to evaluate nerves, effusions, and tendons
Ob/ Gyn Ultrasound- Best tool, Fetal, ovarian pathology, and uterine pathology Order transabdominal and transvaginal when possible MRI- usually with and without Endometriosis, adenomyosis, malignancy, fibroids (UFE planning), fistulas CT- order with post op, trauma, PID with abscess, not as useful as MRI or US
Head and Neck CT Face- for trauma without, for infection with Sinus disease- without Neck- almost always with contrast MRI not as good for small lesions due to worse spatial resolution Ultrasound- Thyroid, carotid arteries, palpable masses Nuclear medicine- thyroid, parathyroid
Vascular CTA- vascular disease in any distribution, trauma, dissection, aneurysm, renal artery stenosis, graft eval, and mesenteric ischemia MRI- can be done without contrast, typically done when pt cannot receive CT contrast Ultrasound- carotids, extremities, DVT, aneurysm/pseudoaneurysm
Breast Screening: Mammography in asymptomatic patients Diagnostic Mammography: patients with symptoms (palpable lesion, nipple discharge, skin retraction) or recall from abnormal screening Ultrasound: initial imaging for female patients less than 30 Male patients: Start with mammography Consult radiologist at Breast Care Center: 377-4910
Pediatric Imaging Radiographs, CTs, and Nuclear Medicine use ionizing radiation Start with plain film use others with discretion MRI and ultrasound do not use radiation Most children can tolerate ultrasound MRI difficult due to motion artifact- usually requires sedation Must be still for a long time, narrow tube with loud noises
Fluoroscopy Abd/pelvis- barium swallow, upper GI, small bowel follow through, barium enema, fistula studies, typically done with barium unless worried about fistula or leak then use water soluble contrast (Omnipaque) Chest- Sniff test for diaphragm paralysis Musculoskeletal- Arthrograms, usually followed by MRI Brain/Spine- Lumbar punctures, myelograms followed by CT OB/GYN- HSG, Enema for fistula
Tools for Decision Making Green Card- Provided by Premier Radiology ACR Appropriateness criteria- google ACR Appropriateness Call Radiology NMMC Radiology- 377-4068 NMMC Interventional- 377-5225 Ask Dr. Google
Questions?