Week 8 - CXR and Interstitial Lung Disease Flashcards
1
Q
What should/shouldn’t be included on a chest x-ray?
A
- Inclusion: (need to see: )
— 1st rib
— Lateral margin of ribs
— Costophrenic angle - Rotation assessment:
— Look at spinous processes and clavicle
• Should be in the centre - Lung volume:
— Normal = 5th – 7th anterior ribs at mid clavicular line
• An adequate inspiratory film (i.e. breath!)
— Problems with incomplete inspiration:
• Big heart
• Increased lung markings
• May be indicative of lung disease but may be that the radiographer has not got the patient to take a big enough breath
— Exaggerated expansion
• Obstructive airways disease
• But some patients can take too big a breath (e.g. men who workout at the gym a lot) - Penetration:
— Degree to which the x-rays have passed through the body
— Adequate penetration:
• Vertebrae just visible through heart
• Complete left hemidiaphragm is visible
— Can digitally manipulate the x-ray if penetration is not good enough
• Can make the image a lot clearer - Artefact:
— External/iatrogenic material which obstructs view
• Clothes
• Hair
• Surgical/vascular lines
• Pacemaker
2
Q
How should you review a chest x-ray?
A
- Patient demographics
- Projection
- Adequacy
- – Check rotation
- – Inspiration
- – Penetration
- Airway
- – Trachea
- – Bronchi (check hila)
- Breathing
- – Lungs
- – Pleural spaces
- – Lung interfaces – things that border the lung
- Circulation
- – Look at aortic arch
- – Look at heart
- – Pulmonary vessel (check hila)
- – Right heart border
- – Left heart border
- Diaphragm and bones
- – Free gas
- – Nodules
- – Fracture/dislocation
- – mass
- Review areas that are commonly missed:
- – Apices
- – Thoracic inlet
- – Paratracheal stripe
- – AP window
- – Hila
- – Behind heart
- – Below diaphragm
- – Bones
- – Edge of films
3
Q
What is the silhouette sign?
A
- Adjacent structures of differing density form a crisp silhouette
- – Heart next to lung = white next to black
- Loss of this contour can locate pathology
- – Loss of silhouette sign
4
Q
What is mediastinal shift?
A
- An adequately centred image, but mediastinum is not central
- Look at trachea and cardiac shadow
- Can be pushed or pulled:
- – Push = increase volume or pressure
- – Pull = decrease volume or pressure
5
Q
What is a pneumothorax?
A
- Air trapped in the pleural space
- Venous return dropped due to high thoracic pressure
- Spontaneous, or as a result of underlying lung disease
— Most commonly due to trauma
• Laceration of the visceral pleura by a fractured rib - Large if: lung edge measures more than 2cm from the inner chest wall at the level of the hilum
6
Q
What are some signs of a pneumothorax on a x-ray?
A
- Visible pleural edge
- Lung markings not visible beyond this edge
- Tension pneumothorax: tracheal or mediastinal shift away from the pneumothorax and depressed hemidiaphragm
- – Shift is due to push from the air in the pleural cavity
- – Affected lung is completely compressed
7
Q
What are some x-ray signs of a pleural effusion?
A
- Uniform white area
- Loss of costophrenic angle
- Hemidiaphragm obscured
- Meniscus at upper border
8
Q
What is a lobar lung collapse?
A
Volume loss within lung lobe Causes: - Luminal --- Aspirated foreign material --- Mucous plugging --- Iatrogenic - Mural --- Bronchogenic carcinoma - Extrinsic --- Compression by adjacent mass
9
Q
What are some x-ray signs of a lobar lung collapse?
A
- Elevation of the ipsilateral hemidiaphragm
- Crowding of the ipsilateral ribs
- Shift of the mediastinum towards the side of atelactasis
- Crowding of pulmonary vessels
10
Q
What are some x-ray signs of a consolidation?
A
- Dense opacification
- Volume preserved +/- increased
- Air bronchogram
11
Q
What is a space occupying lesion?
A
- Nodule (3cm)
- Single vs multiple
- Causes:
— Malignant (primary or metastases)
— Benign mass lesion
— Inflammatory (e.g. may be TB)
— Congenital
— Mimics
• Bone lesion
• Cutaneous lesion
• Nipple shadow
12
Q
What is a consolidation?
A
Filling of small airways/alveoli with:
- Pus
- Blood
- Fluid
- Cells (tumour)
13
Q
How do you calculate the cardiac index?
A
- Widest part of the heart and ribcage are measured laterally
- Ratio
- – Normal
14
Q
What is interstitial space?
A
A potential space between alveolar cells and the capillary basement membrane
- Only apparent in disease states
- It may contain fibrous tissue, cells or fluid
15
Q
What is the pathophysiology of interstitial lung disease?
A
- Only apparent in disease states
- It may contain fibrous tissue, cells or fluid
16
Q
What are some causes of interstitial lung disease?
A
- Occupational:
- – Asbestosis
- – Silicosis
- – Coal workers - pneumoconiosis
- Treatment related:
- – Radiation
- – Methotrexate
- – Nitrofurantoin
- – Amiodarone
- – Chemotherapy
- Connective tissue disease:
- – Rheumatoid arthritis
- – Systemic lupus erythematosis
- – Polymyositis
- – Schleroderma
- – Sjogren’s
- Immunological:
- – Sarcoidosis
- – Hypersensitivity pneumotitis / Extrinsic allergic alveolitis
- Idiopathic:
- – Fibrosing alveolitis (IPF = idiopathic pulmonary factor)
17
Q
What is asbestosis?
A
- Inhalation of asbestos fibres
- Disease often develops long after exposure
- Asbestos inhalation is associated with:
- – Benign pleural plaques
- – Asbsestosis (pulmonary fibrosis)
- – Mesothelioma
- Asbestos fibres that penetrate to the alveoli produce alveolitis
- History of asbestos exposure
- Patient breathless on exertion and a dry cough
- Inspiratory crackles at the lung bases, which rise as the disease advances
- No treatment
- Lung function tests show small lungs, reduced compliance and impaired gas transfer
18
Q
What is sarcoidosis?
A
- Incidence is highest in 30-40 year olds
- Often asymptomatic
- – May have cough, breathlessness
- Non-caseating granuloma
- Differential diagnosis = lymphoma, TB
- Disease of unknown cause
- Fluid is collected by lavage of the airways
- Alveoli contain lots of cells
- – Including macrophages and lymphocytes
19
Q
What is hypersensitivity pneumotitis / extrinsic allergic alveolitis?
A
- Inhalation of organic material triggers an allergic reaction in alveoli and bronchioles
- May be:
— Sudden onset and rapidly progressing (acute)
— Develop gradually and persist (chronic) - E.g. farmer’s lung = acute form
— Antigen = thermophilic actinomycetes found in mouldy hay
— Influenza like illness 4-9 hours later
— Fine mid and late inspiratory crackles
— May be a wheeze
— The chest x-ray shows a diffuse micro-nodular infiltrate
• Denser towards the hila - E.g. bird fancier’s lung = chronic form
— Long term antigen exposure = pigeons, budgerigars
— Insidious malaise
— Dry cough and breathlessness
— Inspiratory crackles
— Chest x-ray may be almost normal, progressing to fibrosis in late disease - No finger clubbing
20
Q
What is fibrosing alveolitis?
A
- Most common type of interstitial disease in 60-80 year olds
- Progressive inflammatory condition
- Cause is unknown
- Evidence of increased numbers of activated alveolar macrophages
— Attract neutrophils and eosinophils which produce local lung damage
• Generate reactive oxidant species and proteases
— Results in tissue destruction and fibrosis - Median survival = 3 years
- Patients present with:
— Progressive shortness of breath on exercise
— Non-productive cough
— Bilateral insiparatory fine crackles
— Finger clubbing - Progresses at different rates in different patients
- Chest x-ray shows small lungs with micro-nodular shadowing predominating in the lower lobes, with ragged heart borders
- Can be restrained by treatment with high dose oral steroids
— Less effective once fibrosis has developed
21
Q
What are the signs and symptoms of interstitial lung disease?
A
Symptoms: - Shortness of breath --- Insidious onset --- Gradual worsens - Reduced exercise tolerance - Dry cough --- Can cause stomach pain Signs: - Tachypnoea - Tachycardia - Reduced chest movement - Coarse crackles - Cyanosis may be present - Signs of right heart failure may be present
22
Q
What can interstitial lung disease affect, other than the interstitium?
A
- Alveoli lumen
- Bronchioles
- Acini
- Bronchiolar lumen
- Possibly chest wall
23
Q
Describe the typical chest x-ray picture of patients presenting with interstitial lung diseases
A
- Fibrosing alveolitis:
- – Small lungs
- – Micro-nodular shadowing
- – Ragged heart borders
- Extrinsic allergic alveolitis – acute
- – Micro-nodular infiltrate
- – Denser towards the hila
- Extrinsic allergic alveolitis – chronic
- – Almost normal
- – Progresses to fibrosis in late disease
- Sarcoidosis
- – Miliary and nodular shadowing
- – Diffuse fibrosis
- Asbestosis
- – Plaques
- – Fibrosis
- – Mesothelioma
24
Q
What occupation and exposure is associated with asthma?
A
O = lab worker E = rat urine
25
Q
What occupation and exposure is associated with diffuse fibrosis?
A
O = boiler/pipe laggers, railway/construction E = asbestos
26
Q
What occupation and exposure is associated with nodular fibrosis?
A
O = coal miner, miner, demolition E = coal dust, silica, asbestos
27
Q
What occupation and exposure is associated with alveolitis?
A
O = farmer, pigeon fancier E = fungal spores from hay, avian antigens
28
Q
Describe pleuritic chest pain
A
- Severe
- Sharp
- ‘knife-like’ pain
- Worse with inspiration
29
Q
How does pleural fluid production occur?
A
- By capillary filtration at the parietal pleura
- Increased:
- – Lung interstitial fluid
- – Hydrostatic pressure
- – Permeability
- Decreased:
- – Oncotic pressure
30
Q
How does pleural fluid absorption occur?
A
- Via lymphatic drainage
- Decreased:
- – Lymphatic blockage
- Elevated:
- – Systemic venous pressure
31
Q
What is a pleural effusion and what are the different types?
A
Any collection of extra fluid in the pleural space
- Haemothorax = blood
- Chylothorax = chyle (lymph with fats in it)
- Empyema = pus
- Simple effusion = serous fluid
32
Q
What can cause transudate?
A
- Increased hydrostatic pressure
- – Cardiac failure
- Decreased capillary oncotic pressure
- – Hypoalbimunaemia
- – Nephritic syndrome
- Increased capillary permeability
- – Sepsis
33
Q
What can cause exudate?
A
- Neoplasms
- – Cancer involving pleural surface
- – Secondary’s from breast, lung, ovarian, GI, lymphoma
- – Primary tumour of pleura
- Infection
- – Pneumonia, TB
- Immune disease
- – Connective tissue diseases
- Abdominal disease
- – Pancreatitis, ascites, subphrenic abscess
34
Q
Describe pleurisy
A
- Produces a sharp pain worse with large breathing movements
- – E.g. coughing, sneezing, laughing
- People take small breaths and often hold the affected side of the chest
- Involvement of the diaphragmatic pleura causes pain in the shoulder on the same side
- Characteristic physical sign = Pleura rub
- – A creaking noise heard through a stethoscope in concert with respiratory movements
35
Q
What are some causes of pleurisy?
A
- Infection (most common cause)
- – TB
- – Pneumonia
- Autoimmune
- – Rheumatoid arthritis
- – Systemic lupus erythematosis
- Lung cancer
- Pneumothorax
- Pulmonary embolism
36
Q
What is pleural fibrosis?
A
- May develop as a result of unabsorbed pleural effusion
- A small degree of pleural thickness may produce no effects
- Wide spread fibrosis restricts the expansion of the lung
- – There is a measurable reduction in lung volumes and compliance
37
Q
Describe pleural tumours
A
- Secondary deposits of tumour are not uncommon in the pleura
- The commonest primary tumour = malignant mesothelioma
— Practically all victims have been exposed to asbestos 20-40 years before
— Early symptoms = those of pleural effusion
• The chest pain is duller and more diffuse than that of pleurisy
• As the disease progresses, pain and breathlessness become increasingly severe and there is increasing weight loss
— Physical signs = those of a large pleural effusion
— Prognosis is poor
38
Q
What are some congenital abnormalities of the chest wall?
A
Deformity of the ribs, sternum and thoracic spine
- Sternal abnormalities rarely produce functional impairment
- – Cosmetic impact is considerable
- Scoliosis and kyphosis may produce significant functional impairment of the thoracic cage
- – Sometimes congenital
39
Q
What are some acquired abnormalities of the chest wall?
A
- Trauma, kyphosis, scoliosis and ankylosing spondylitis
- Trauma:
- – Broken ribs produce pain and possible underlying lung contusion
- – There may be a pneumothorax
- Some old patients may have had surgery for TB
- – Designed to collapse underlying lung
