Overview: Radiography + Med. Imaging Flashcards
Radiology Principles (3)
- Based on ability of x-rays to penetrate tissues and organ
- Rate of penetration depends on organ/tissue density - Greater density = opaque image - Lesser density = transparant image
- All radiation studies involve some exposure to harmful radiation, choose scans wisely
Radiography presentations of body structures (5)
- Healthy bones = white
- Bone fx = radiolucent line
- Osteoporotic bone = gray/porus
- Healthy lung/bowel = black
- Other structures (musc/bld/organ/misc tissues) = black
Radiography views (3)
- AP = x-rays pass front → back
- PA = x-rays pass back → front
- Oblique = x-rays pass @ angle
Types of radiography studies (3)
- Plain films
- Fuoroscopy
- CT scan
Define Fluoroscopy
- Fluoroscope used to visually examine target
- Utilizes the following tools:
- X-ray source
- Fluorsecent screen
- More radiation exposure than plain film
- Allows for real time images
Define CT Scan
- Integrated view of multi-angled x-rays
- Each x-ray represents a “slice,” selection of tissue @ specific level
- Variation of density allows for variable penetration
- Permits exam. of tissue that would otherwise obscure due to surroundings
- Presents with various shades of black/gray on images
Plain x-ray indications (5)
Suspision of the following:
- Trauma/injury
- Infection
- Tumor
- Arthritis
- Bone spurs
Spinal x-ray indications (5)
Suspicion of the following
- Trauma
- Degenerative changes
- Tumor mets
- Spondylollithesis
- Scoliosis
Define Spondylolithesis
Slipage of 1 vertebral disc over another, causing vertebral column dysfunction
Chest x-ray Indications (5 structures, 8 general conditions)
Evaluate…
- Heart
- Lungs
- Bony thorax
- Mediastinum
- Great vessels
For these conditions
- Tumors
- Infections
- Pleural fluid
- Pulmonary edema
- COPD
- Pneumothorax
- Rib fx
- Thoracic vert. fx
General Kidney, Ureter, Bladder x-ray (KUB) Indications (3)
- Intestinal obstruction
- Soft tissue masses
- Ruptured viscus
Note: **Often the most cost effective measure for ruling in GI/GU pathology
Abdominal CT Indications (3 general, 1 c 8 common examples)
- CT-guided needle biopsy
- Diagnosing/staging neoplasms
- Monitor and diagnose abdo disease
- Abcess
- Inflammation
- Perforated bowel
- Intestional obstruction
- Calculi
- Tumors (adrenal, liver, pancras)
- Pseudocysts
- Trauma (esp. splenic hematoma)
Brain CT Indications (7)
Diagnosis of the following
- Brain tumor
- Cerebral infarction
- Ventricular displacement/enlargement
- Cortical atrophy
- Bleeding/AV malformation
- Hematoma
- MS
Chest CT Indications (6)
Aid in the diagnosis of the following pathologies, esp when CXR dues not suffice
- Tumor
- Nodule
- Abcess
- Pleural effusion
- Enlarged lymph nodes (often in the presence of lung and mediastinum dysfunction)
- Pulmonary embolism (via spiral CT)
Spiral CT (definition, 2 major uses)
Definition: CT scan technique involving continuous movement of pt through the CT scanner. Allows faster scanning c incrased definition of internal structures
Uses: Visualization of the following
- Blood vessels
- Internal tissues