Radiology Flashcards
Name six imaging modalities
- Plain radiography
- Contrast studies
- Ultrasound
- CT
- MRI
- Nuclear medicine
What are contrast studies?
General term for any agent that improves visualisation of anatomy
What is the contrast agent used in MRI?
Gadolinium
What is plain radiography used to visualise in head and neck?
- Lateral soft tissue
- Facial views (maxillofacial)
- Orthopantomogram (dental assessment)
What changes are made to visualise bone and soft tissue when using pain radiograph?
Soft tissue uses lower dose radiation, and bone requires high radiation does to eliminate soft tissue
If cancers have spread to the bone, what T stage are they usually?
T4 - advanced stage of disease
What contrast agents are used in contrast studies?
Barium and iodine based water soluble contrast media
Barium toxic outside of GI tract, use water soluble one instead if you suspect perforation
What is a sialogram?
Radiographic examination of the salivary glands using contrast agent
What is a sonogram?
X-ray procedure that is done to visualize any abnormal opening (sinus) in the body, following the injection of contrast media (x-ray dye) into the opening.
What is videofluoroscopy?
X-ray that looks at the way your swallowing works with use of barium
What is the significance of a functional vs mechanical videofluoroscopy?
Function looks as if something has stopped working i.e. due to stroke or operation, whereas mechanical is looking at if there is something physically obstructing the pathway i.e. tumour or stricture
What are the investigations used to determine swallowing function of a patient?
- Videofluoroscopy
- Speech therapist
- Blom-singer valve assessment
What is a blow-singer valve?
Tube used after laryngectomy which connects trachea and oesophagus – initially oesophageal speech (belching) then develop a degree of speech
What is an ultrasound used for?
- Solid vs cystic masses
* Vascularity (doppler)
What forms of ultrasound investigation are there?
- Doppler
* Ultrasound guided FNA
What are the features of CT?
- Radiation
- Cross sectional but now MPR and 3D
- Uses contrast (oral, IV)
- Bony detail (MRI more soft tissue)
Can CT be used to diagnose sinusitis?
No, only used for planning for surgery if patient has reoccurring sinusitis but is unresponsive to meds
What is the clinical significance of fascia of the neck spaces?
Useful to contain infection between different spaces, but can spread daily up and down the same space and can travel to the base of the skull and infection can become intercranial
What is the danger space of the neck?
Region of space in the neck behind the pharyngeal space where infection has the potential to spread to the mediastinum
What are paraganglionomas?
Benign tumour of paraganglia cells in the carotid arteries (maintain blood pressure and physiology), usually arises in the carotid bifurcation
What investigation can be used to visualise paraganglionomas?
CT scan - very vascular tumour so takes up the contrast
10% are multiple, so if you see one, you must look for others
What are the features of MRI?
- No radiation
- Tissue characterisation
- Uses different sequences resulting in a particular image appearance (T1, T2, STIR)
- Contrast (gadolinium)
- Contraindications
What are T1 and T1 images in MRI?
The timing of radiofrequency pulse sequences used to make images results in images which highlight fat tissue within the body.
What are different types of nuclear medicine?
- Isotope bone scan
- Thyroid/Parathyroid
- Positron emission tomography (FDG)
Can PET scan identify TYPES of tumours in the body?
No, only identifies SITES as other conditions also have high glucose metabolism rates
Therefore need biopsy to determine
