CCP 212 - Radiology Flashcards
The 9 steps of CXR interpretation are:
- Patient identifiers/labels
- Previous imaging
- Type of film
- Adequacy (inspiration, penetration, and rotation)
- Tubes/toys
- Soft tissue
- Bone
- Mediastinum
- Lungs
ETT Height should be ‘x’ above carina?
5cm above carina.
This allows for head flexion & extension without “pushing” the tube into the R bronchus.
Deep sulcus sign indicates ___.
Pneumothorax.
T or F:
NG appears bigger than OG tube on CXR.
True.
NG tube has a radiopaque line that creates this illusion.
Silhouette sign is described as ___.
Blurring of the interface between structures on CXR.
What makes up the right heart border on CXR?
The RA.
What makes up the left heart border on CXR?
The LV AND LA. The LA only makes up 1/4 of the left heart border.
The cardiothoracic ratio (CR) is:
Maximum diameter of heart, compared to the maximum diameter of inner rib margin.
Cardiomegally suspected when the cardiothoracic ratio exceeds ___.
> 0.5 in PA.
> 0.6 in AP.
Language used to communicate increased pulmonary opacities:
- Focal airspace disease.
- Diffuse multi-focal airspace disease.
- Fine reticular patterns.
Silhouette sign is useful in determining:
ie. silhouette sign against right heart border
Affected lobes in lung disease.
ie. right middle lobe opacity
Air bronchograms can be described as:
A region of bronchiole that is surrounded by increased opacity, highlighting the air-filled bronchiole.
The 3 radiographic stages of CHF are:
Stage 1 = Cephalization (thickening of upper lung vascular markings relative to lower lung vasculature)
Stage 2 = Interstitial Pulmonary Edema (increased interstitial markings + pulmonary venous HTN)
Stage 3 = Airspace Pulmonary edema (air space filling with diffuse and patchy distribution; “bat wing”)
Non-central distribution patterns of pulmonary edema on CXR can usually be attributed to:
Non-cardiogenic causes of pulmonary edema (ie. negative pressure from choking/laryngospasm, ARDS, etc).
The two main indications for abdominal XR are:
- Perforation
2. Obstruction
Free air under the diaphragm indicates ____.
Perforation.
Air should always be contained within the bowel.
Free air in the abdomen post-surgery (from CO2 injection) may last for up to __ days.
10 days.
Free air should not be increasing over serial abdominal XRs.
Rigler’s sign is:
Visible bowel wall from air on both sides of the bowel wall.
Large bowel vs small bowel identification on XR:
Large bowel = Presence of haustra.
Small bowel = Presence of valvulae conniventes.
Haustra are:
Sac-like pockets that make up the large bowel. Mucous folds DO NOT cross the full width of the large bowel.
Valvulae conniventes are:
Mucousal folds of the small bowel. They cross the full width of the small bowel on abdominal XR.
Retroperitoneal free air can be caused by:
Perforation of an organ within the retroperitoneal space (ie. the ascending colon).
Air in the biliary tree is called:
Pneumobilia.
Pneumatosis intestinalis is:
Air in the bowel wall.
Presence of MULTIPLE air fluid levels usually indicates:
Complete bowel obstruction.
A partial obstruction should allow for passage of gas.
A volvulus is:
Bowel twisting onto itself, causing obstruction.
The “Free ABDO” acronym for abdominal XR interpretation stands for:
Free air Air Bowel wall Density Organs
The “ABCS” of cervical spine XR stand for:
Alignment
Bone
Cartilage
Soft tissue
When assessing alignment on cervical spine XR, identify these four lines:
- Anterior vertebral line.
- Posterior vertebral line.
- Spinolaminar line.
- Posterior spinous line (curved).
Ensure these lines are SMOOTH and CONTINUOUS.
Odontoid view is used for:
Visualization of C1 and C2.
Spinal XR is generally only used by CCPs for:
Looking for abnormalities and displacement from C1 to T1.
The “ABBCSS” of CT head stand for:
Asymmetry Blood Brain CSF Skull Scalp
Subdural hematoma CT features:
Chronic subdural may appear black (clotted).
Acute subdural will appear white.
Subdural hematoma don’t cross midline.
Epidural hematoma CT features:
Appears concave, because of the tight adherence of the dura to the skull.
SAH CT features:
Diffuse blood across subarachnoid space. Appears as blood within the cisterns and sulci.
May blunt the appearance of the cerebral peduncles. May also present with obstructive hydrocephalus.
IPH CT features:
Focal opacity in ‘x’ location of parenchyma.
Loss of grey/white differentiation indicates:
Brain injury, primarily DAI.
MRI functions by:
Realigning protons in the body, then allowing them to return to normal. The return to normal produces a deflection and image.
True or false:
MRI uses radiation.
False. It is magnetic.
FAST Algorithm:
If + & stable –> ?
If + & unstable –> ?
+ & stable –> CT
+ & unstable –> OR
High frequency versus low frequency:
High = Higher quality, but less depth.
Low = Lower quality, deeper depth.
Hypoechoic appearance on ultrasound.
Dark (doesn’t bounce back frequency).
Hyperechoic appearance on U/S.
White (dense).
Describe acoustic shadowing on U/S:
Acoustic shadowing occurs when a dense structure produces a shadow behind it.
Describe acoustic enhancement on U/S:
Sound bounces between the proximal and distal walls of a cyst or fluid-filled space. Produces a brighter image on the distal wall of tissue.
Describe reverberation artifact on U/S:
Production of false lines of hyperechoity from “shaking” of the ultrasound wave. Produces comet tails.
Describe mirror image artifact on U/S:
A mirror image is reflected on the opposite side of a dense structure. This occurs in images that have air on the distal side of a dense structure (ie. bladder).
Linear probe is best for assessing:
Shallow structures.
Phased array or curvilinear probes are best for assessing:
Deeper structures (ie. IVC or organs).
“Optimizing” an U/S image refers to:
Centring the image in the screen, and adjusting the gain.
Explain what “Spine sign” is:
Being able to see the spine through a fluid-filled space. This is an abnormal finding when assessing the lung bases, because air will reflect reverberation, rather than producing spine imaging.
What is “BART”?
“Blue away, red towards”. Mnemonic for doppler imaging.
An ONSD of 5.5mm indicates an ICP of ___.
~15 mmHg
Use a ONSD of 6mm for BCEHS CCP purposes
Measurement of the ONSD occurs where?
3mm behind the optic disk. This ensures the area is undistorted by the optic disk.
Why do we use the ONSD as a surrogate for ICP?
It is the only area outside the cranium that is subject to the same pressure that ICP elicits. The ONS is continuous with the subarachnoid space.
ONS contraindications :
1) Depressed skull fracture.
2) Globe trauma.
3) Hydrocephalus.
IVC measurement occurs where?
~2cm caudal to the junction with the hepatic vein.
True IVC measurement is validated when a patient meet the following criteria:
1) Paralyzed
2) PEEP of 5cmH2O
3) ???????
IVC collapsibility index equation:
([IVC max - IVC min] / IVC mac) x 100
Grading scales of SAH?
Hunt-Heiss, Fischer, WFNS.
