Chest Radiology - Respiratory Illness in Children

Chest Radiology

·        Initially:

o   Name, date, and view

o   Orientation: L & R

o   Check exposure: lung fields and intervertebral discs

o   Centering: check rib length on each side for rotation (clavicles unreliable)

o   Lung field size:

§  5 – 7 anterior ribs to the midline of the Right diaphragm

§  7 – 9 posterior ribs to the spine

§  If too many, then hyperinflated: asthma, CF

§  If too few, then inspiratory film: hard to interpret 

·        Middle right lobe is against RH border – consolidation there will obscure border. No other consolidation will

·        Staph pneumonia ® pneumatocele (air filled cysts).  Generally resolve 

·        Pneumo-mediastinum ® „angel wing‟ appearance as air lifts up thymus

·        Chylothorax: lymph surrounding lung in the newborn ® ?thoracic duct dysfunction

·        Trachea: in an infant is floppy, so in an expiratory film can have a kink

·        Lateral CXR:

o   Vertebrae should get blacker as go down

o   Retrosternal clear space: in infant whiter due to thymus

·        Thymus on AP CXR:

o  Lots of variation – can look like large heart

o  Thymic notch: lower right or left edge as it abuts the heart

o  Thymic wave sign: contour down the side of the thymus

o  Thymic sail sign: sail-like shape sticking into the lung fields

·        Respiratory Distress Syndrome:

o  = Alveolar collapse (not bronchi)

o  Xray: diffuse opacity, air bronchograms and small lung volume

o  Severity assessed by blurring of heart borders and diaphragm

o  Group B Strep infections in full term babies can look a bit like it

·        Transient Tachypnoea of the Newborn:

o  Xray: Retained lung fluid, lung volumes normal to large, and pleural effusions 

o  Mild ® recover

·        Meconium Aspiration: 

o  Xray: Diffuse, coarse lung field opacity (fluffy), hyperinflated (airway pathology not air space pathology ® plugging and ball/valve effect) 

o  Can get pneumothorax, pleural effusions due to the work of breathing 

o  Mainly in term babies – they have the grunt to suck it down. Also, pre-term babies less likely to pass meconium when stressed