Radiology of the Thorax (Part 2) Flashcards
How are tests ordered for a pulmonary thromboembolism?
Is another diagnosis unlikely?
Is there a major risk factor?
Is the D-Dimer raised?
Major risk factors for pulmonary thromboembolism?
Recent immobility Major surgery Pregnancy/post-partum Previous VTE Major medical illness Lower limb trauma or surgery
When is D-dimer measured?
If only 1 of the major risk factors is present
Describe the D-Dimer test?
Very sensitive so lots of people without a pulmonary embolism are diagnosed
Describe a V/Q scan
If chest x-ray is normal, then do a V/Q ratio
Good way of ruling out a PE
Normally, with areas of normal ventilation there will be lack of perfusion (as blood is directed to regions with good ventilation); but if no blood is being sent to normal ventilation areas, a PE is likely
If chest X-ray is abnormal, or if a massive PE is suspected, what should be done?
Order a pulmonary angiogram
Test for suspected DVT?
Leg ultrasound
Clinical features and pathology of lung cancer?
Asymptomatic - 15-25% of diagnosis, particularly peripheral tumours
Symptoms - cough, wheeze, haemoptysis, recurrent pneumonia, hypercalcaemia, weight loss, hoarseness, finger clubbing, persistent supra-clavicle nodes
Predisposing factors to lung cancer?
Inhalation of carcinogens, like cigarette smoke, asbestos, etc
Bronchioalveolar adenoma
Lipoid pneumonia
Interstitial pulmonary fibrosis
Previous lung cancer (tumours can be synchronous and metachronous)
Types of lung tumours?
Peripheral tumours (arise beyond the hilum) Central tumours (arising at/close to the hilum)
What is a hilum?
In relation to lungs - LUNG ROOTS
Describe peripheral tumours
Rarely visible on chest x-way if
Cardinal signs of central tumours?
Hilar enlargement
Distal collapse/consolidation
International Staging System?
Tumour size
Intrathoracic lymph node staging
Metastases
What are calcified pleural plaques markers of?
Marker of exposure to asbestos; will likely also have pulmonary fibrosis
Describe PET CT
Positron Emission Tomography CT scan
Glucose is given and it goes to regions of high glucose metabolism (tumours)
What can PET CT be used for?
Very good at detecting:
Nodal metastases
Distant metastases (not brain metastases though)
Delineating tumour in an area of collapse
Describe MR staging of tumours
Does not require IV contrast to see vessels and has better soft tissue differentiation (however, spatial resolution is better with CT)
It is costly, time-consuming, and requires gating to reduce motion artefacts
3 planes valuable at apex, aortapulmonary window and subdiaphragmmatic recess
What can ultrasound be used to look for?
Pleural effusion
Subphrenic collection
Movement of diaphragm
US guided drainage
What is SOBOE?
Shortness Of Breath On Exertion
