18 Introduction to Chest Radiology 1 (2) Flashcards
1
Q
Normal chest radiograph
- Components
- Search pattern
- Concept
A
- Components
- Standard views
- Radiographic densities
- Film exposure
- Chest CT
- Search pattern
- Heart
- Mediastinum
- Lungs
- Chest wall
- Concept
- Place area of interest next to cassette
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/228/795/a_image_thumb.png?1659437432)
2
Q
Standard radiographic views
A
- Postero-anterior (PA)
- Antero-posterior (AP)
- Left lateral CXR
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/229/036/a_image_thumb.png?1659437433)
3
Q
Postero-anterior (PA) CXR
A
- X-ray traverses posterior to anterior
- Heart next to cassette
- Patient is upright
- 6 feet from X-ray tube
- Decrease image magnification
- Increase sharpness
- Full inspiration
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/229/146/a_image_thumb.png?1659437434)
4
Q
Antero-posterior (AP) CXR
A
- X-ray traverses anterior to posterior
- Patient upright, supine
- Spine next to cassette
- 3 feet from x-ray tube
- Increase image magnification
- Decrease sharpness
- PA is preferred
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/229/321/a_image_thumb.png?1659437434)
5
Q
Left Lateral CXR
A
- X-ray traverses R –> L
- Left side next to film
- Heart & aorta on left
- Decrease magnification
- Evaluate behind heart
- Summation of lungs
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/229/478/a_image_thumb.png?1659437435)
6
Q
5 radoigraphic densities
- 5 radiographic densities
- Anatomic structures differ in density
A
- 5 radiographic densities
- Air - lungs, trachea
- Fat
- Soft tissue - fat, blood, muscle
- Bone - calcium
- Metal - hardware, contrast
- Anatomic structures differ in density
- Low density material (air) represented as black
- Dense material (bone, metal) represented as white
- Body tissues are varying degrees of grey
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/229/587/a_image_thumb.png?1659437435)
7
Q
Image exposure
- Unexposed X-ray film
- Anatomic structures differ in density
- Dense tissue
A
- Unexposed X-ray film starts off as white
- When radiated, the silver ion (black) in x-ray film emulsion precipitates
- The more radiation that X-ray film receives, the blacker it becomes
- Anatomic structures differ in density
- Attenuation of X-rays depends on density and thickness of tissues
- X-ray image is a map of X-ray attenuation
- Dense tissue (bone) blocks more radiation from reaching the film
- Air – black
- Soft tissue – grey
- Bone – white
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/229/686/a_image_thumb.png?1659437436)
8
Q
Computed axial tomography (CT)
A
- Cross-sectional imaging
- Computer processing and reconstruction
- Superior tissue contrast, anatomic localization
- Bread-slicer, view from feet
- Helical multi-detector technique
- High radiation dose
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/230/728/a_image_thumb.png?1659437437)
9
Q
Computed axial tomography (CT)
- Helical multi-slice CT acquisition
- Multi-detecter helical CT
- High resolution chest CT (HRCT)
A
- Helical multi-slice CT acquisition
- Interpolated data from 4 detector rows
- 4, 16, 64, 128, –> 320 MDCT
- UPMC: 64 MDCT is the work horse
- Multi-detecter helical CT
- Scout image
- Breathe in
- Hold it (~20s)
- Breathe
- High resolution chest CT (HRCT)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/231/579/a_image_thumb.png?1659437437)
10
Q
MDCT: axial data set
A
- Stack of images
- Axial plane
- 300 - 500 images
- 0.63 mm thin
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/232/036/a_image_thumb.png?1659437438)
11
Q
CT contrast bolus timing
A
- Start IV contrast before the CT
- Scan continuously at one level
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/232/264/a_image_thumb.png?1659437439)
12
Q
Shortness of breath
A
- Pulmonary emboli
- Venous blood clots travel to lung
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/232/573/a_image_thumb.png?1659437440)
13
Q
Radiation dose
A
- PA & lateral CXR
- 20 mrem = 0.2 mSv
- ~10 days natural background radiation
- Chest CT
- Equivalent to 400 CXR
- 3-5 rad = 5 mSv
- ~ 2 years background radiation
- 1 mSv = 5+ cancers per 100,000 individuals
14
Q
Search pattern
A
- Heart
- Mediastinum
- Lungs
- Pleura
- Hila
- Trachea & bronchi
- Pulmonary arteries
- Pulmonary veins
- Chest wall
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/233/195/a_image_thumb.png?1659437441)
15
Q
The heart
- Location
- 2 parallel pumps
- Heart size
- Heart borders
- Right
- Left
A
- Left of midline
- 2 parallel pumps
- Right
- Low pressure
- Deoxy blood to lung
- Left
- High pressure
- O2 blood to body
- Right
- Heart size: < half diameter of thorax
- Post-partum cardiomyopathy: heart is too big
- Heart borders
- Right
- SVC & RA
- Left
- Aortic arch
- Main pulmonary artery
- Left ventricle
- (Left atrial appendage)
- Right
![](https://s3.amazonaws.com/brainscape-prod/system/cm/117/233/261/a_image_thumb.png?1659437441)