Clinical Imaging of the Thorax Part 2: Thorax Imaging (AS lecture) Flashcards
what are 4 advantages to CT scans
- less expensive than MRI
- quicker than MRI so good for emergency situations
- can identify internal bleeding, cancer development, tumours and fractures
- whole body does not need be inside the scanner so patients wont feel claustraphobic
what are 3 advantages of MRI
- produces more detailed image than CT scans
- don’t use radiation, so safer to use
- can identify pathologies in soft tissues, joints, organs brain and heart better than CT scans
what are 3 disadvantages of CT scans
- uses small doses of radiation, so can increase risk of cancer in later life
- not recommended for pregnant women as radiation is teratogenic
- contrast dye is used during the scan sometimes which may cause an allergic reaction in some patients
what are 5 disadvantages of MRI scans
- loud so people might find it stressful
- metal must be removed before the scan (jewellery, clothing etc)
- medical or metal implant can interfere with MRI scan
- can be claustrophobic for some patients
- contrast dye is used sometimes which can potentially cause an allergic reaction
Ultrasound scans
what are some uses for Ultrasound scans
- investigations of the Pelvis/ abdominal organs
- identify vascular pathologies
- fetal aging
- musculoskeletal scans
- breast scans for tumours
how does a VQ scan work
- radioactive material is breathed in via nebuliser and then pictures are taken to look at airflow in the lungs via a gamma camera
- a different radiactive material is injected into an arm vein and then more pictures are taken to see the blood flow in the lungs
what is the aim of a VQ scan
- aim is to look for evidence of any pulmonary embolism in the lungs that could be fatal
PER scan
how does PET scan work
injected tracer collects into body areas of higher levels of metabolic/biochemical activities to pinpoint the disease location
what do SPECT scans do
- produc es images that show how well blood is flowing in the heart and brain, which areas of the brain are active and which bones are affected by cancer
what is an endoscopy
- medical precedure that uses an endoscope to examine the interior of a hollow organ or body cavity by introducing endoscopes directly into the organs
what is 1 X-ray findings in an upright patient with pleural effusion vs the 4 found in a supine patient with pleural effusion
Upright:
- “meniscus” is seen obscuring costophrenic angle, heart borders and hemidiaphragm due to fluid build up
Supine:
- loss of costophrenic angle
- increased density of affected hemithorax
- pseudo-elevation of diaphragm
- loss of lower lobe vessels
all due to fluid build up
meniscus here is a concave line obsurring costophrenic angle, heart borders and the hemidiaphragm
what are 3 CT findings of a patient with pleural effusion
- sickle-shaped opacity in thorax
- lateral upward sloping of a meniscus-shaped contour
- diaphragmatic contour is partially/completely obliterated
give 4 potential x ray findings in emphysema
- hyperinflated lungs
- low flattened hemidiaphragm
- hyperlucency of the lungs
- increaseed retrosternal airspace
- increased AP chest diameter
- vertical heart
- widely spaced ribs
- sternal bowing
- blunting of the costophrenic angles
give 2 potential CT findings in emphysema
- appearance of dark or low attenuation areas
- overinflation/damage of air sacs
give 3 findings you would see on a chest x-ray/radiograph in a pneumothorax
- visible visceral pleural edge seen as a very thin sharp white line
- no lung markings
- peripheral space is radiolucent compared to adjacent lung
