Pediatric chest
How can bacterial and viral pneumonia's be differentiated on imaging?
-Lobar consolidations more commonly bacterial or caused by mycoplasma -Diffuse, fluffy infiltrate extending into the lung periphery is suggestive of bacterial infection -Central peribronchial opacities with atelectasis are more suggestive of viral, Mycoplasma or Chlamydia infection 13
How do bacterial PNA's present on CT and X-ray?
-Opacities associated with pleural effusion with lobar enlargement and bulging fissure implying large amount of exudate or evolving abscess -Visible cavitation -On CT most bacterial pneumonias demonstrate patchy, segmental or lobar airspace opacities High resolution CT - centri-lobular nodules, ground glass opacities and centrilobular branching structures (similar CT findings may be seen with mycoplasma)
What is a sequestration of the lung?
Aberrant lung tissue with systemic bl. supply usually arising from aorta.
What are causes of recurring pneumonia in same location?
Anatomical based problems: Intrinsic bronchial obstr: for. body, stenosis or tumor. Extrins. compression: mass, vessel or LAD Focal bronchiectasis Anomalous bronchus; tracheal bronchus Pulmonary sequestration, CCAM (cystic adenomatoid malformation have it at site of malformation.)
What should be thought of with LVF failure in first week of life?
Aortic atresia (hypoplastic left heart) Severe (or "critical") CoA or AS Interrupted aortic arch Cardiomyopathy Cardiac ischemia (anomalous coronary artery, birth depression)
What are afterload lesions leading to left heart failure and pulmonary edema?
Aortic stenosis (AS) Aortic coarctation (CoA) Hypoplastic left heart (also known as aortic atresia) Interrupted aortic arch Systemic hypertension
What are causes of recurrent pneumonia in variable locations?
Aspiration: GE reflux, NM disease, poor swallowing, TE fist., esoph. atresia, motility dis, achalasia. Asthma, bronch pulm dyspl. Abn mucociliary fxn: CF, ciliary motility dysf. Downs, bronch diverticulosis. Congential immune def.: eg. dysglobiulinemias, digeorge etc. Acquired immune def: AIDS, BMT Anatomic or fxl asplenia: SSD (strep pneumo, mycoplasma)
When is US used in assessment of PNA?
Assess large or peripheral opacities caused by infection. Acoustic window through thymus and cartilage of anterior ribs and sternum makes US more attractive in children.
What is key imaging finding of CDH?
Bowel in the thorax and displaced mediastinal structures.
What is the progression and presentation of bronchial atresia? What does imaging look like?
Bronchi distal to atretic segment fill with mucus that can't be cleared. Ultim. form a tubular mucocele. Distal airways ventilated w/ collateral paths and demonstrate air trapping causing local hyperinflation. Imaging shows hyperlucent lung with air trapping. Mucous plug may be visible just distal to the obstructed bronchial segment.
What are some possible causes of non-cardiogenic pulmonary edema?
Capillary leak and/or idiopathic: -Acute respiratory distress syndrome -(ARDS)Sepsis -Neurogenic causes -Smoke inhalation -Trauma -Drowning -Drug overdose -Upper airway obstruction -High altitude -Lung transplant Impaired lymphatic or lymph node drainage: -Pulmonary lymphangiectasia Renal Failure and Fluid Overload
What is chronic lung disease of prematurity caused by?
Chronic entity that affects the development of all lung tissues. It is a result of immaturity as well as oxygen toxicity and barotrauma in infants who received prolonged ventilatory support. The pathogenesis is bronchiolar and parenchymal injury due to an underlying condition as well as toxic effects of the treatment. SDD/RDS is the most common underlying disease, Risk of CLD increases when SDD is complicated with PIE.
When is CT considered for evaluation of PNA?
Complicated or recurrent PNA in same location Large opacities, xray can't differentiate pulmonary, mediastinal and pleural involvement. PNA which progresses or fails medical and/or surgical therapy.
What may congenital lobar emphysema be associated with?
Congenital lobar overinflation may be associated an aberrant left pulmonary artery and also with congenital heart defects: TOF, VSD and PDA
How and when does pulmonary interstitial edema present in an infant with RDS/SDD?
Develops in the second to third day of life Air dissects through the perivascular interstitum and lymphatics. Radiographically, it presents as small well-defined round and elongated lucencies. These are distinguished from air bronchogram by the absence of tapering and by greater lucency. Air may become confluent forming air cysts. PIE can be unilateral or bilateral. It increases the likelihood of pneumothorax and pneumomediastinum.
What is used in treatment of severe cases of meconium aspiration syndrome? What is the radiographic appearance of this treatment?
ECMO - The typical radiographic appearance of the is diffuse pulmonary opacification with variable volume loss. Air bronchograms and patchy basilar atelectasis are also common findings. Initial radiographs are useful in confirming the position of bypass cannulae and respiratory tubes. Radiographic improvement lags behind but correlates with clinical improvement.
What are the types of sequestration?
Extralobar: external to pleura, w/ primarily systemic venous drainage. May be below diaphragm near adrenal gland, may mimic adrenal mass. Intralobar: Inside pleura, usually w/ pulmonary venous drainage.
What is pathogen assoc with PNA in newborn?
Group B strep Gram neg. bacilli (ecoli, Klebsiella pneum) Chlamydia (infants 2-3 months)
What may differentiate PNA in cases that present similar in appearance to RDS? What type of pathogen is most likely to cause PNA that presents like RDS on radiograph?
Group B streptococcus can mimic RDS. In such cases, the presence of pleural effusion helps differentiate pneumonia from RDS, since pleural effusion is seen in more than 50 percent of the patients with pneumonia.
What is a CPAM?
Hamartomatous proiliferation of terminal bronchioles that communicate w/ the bronchial tree. Formerly: congenital cystic adenomatoid malformation (CCAM)
What may cause sudden consolidation on x-ray in a previously successfully treated infant with surfactant?
Hemorrhagic edema may follow the treatment with surfactant and produces sudden consolidation. The hemorrhage may result from increased left to right shunt though the ductus arteriosus due to decrease in pulmonary resistance with subsequent hemorrhagic edema.
What combination of findings is seen in untreated RDS/Surfactant deficiency disorder on chest x-ray?
In untreated patients, the combination of atelectasis and exudates produce bilateral symmetric granular (ground glass) opacities with air bronchograms. Low lung volumes are seen unless the patient is on ventilator. In severe cases, diffuse consolidation (white out) which may reflect edema and hemorrhage are noted. After one week, the opacities start to resolve from the periphery to the center and from the upper to lower portions of the lung.
In general, what is the pattern of presentation of bronchopulmonary foregut malformations?
Inverse spectrum of normal to abnormal vasculature inverse in severity of normal to abnormal lung parenchyma.
what side is congenital diaphragmatic hernia normally seen?
Left (Bockdalek) Right side associated with greater risk of comorbidities and has poorer prognosis.
Where do most defects occur in the diaphragm with CDH and what is usually the primary complication associated with CDH?
Left posterior diaphragm Pulmonary hypoplasia
What are preload lesions leading to LVF and pulmonary edema?
Left to right shunt lesions: -Atrial septal defect (ASD) -Ventricular septal defect (VSD)Atrioventricular canal (AV Canal or endocardial cushion defect (ECD) -Patent ductus arteriosus (PDA) -Aorticopulmonary window (AP window) Total anomalous pulmonary venous return with intracardiac shunt Mitral or aortic valve regurgitation Non-cardiac high flow states: -Peripheral arteriovenous (AV) fistula such as vein of Galen "aneurysm" -High flow vascular tumor such as hemangioendothelioma or hemangioma -Anemia such as sickle cell disease -Thyrotoxicosis
What is congenital lobar emphysema and how does it present??
Lesion of abnormal lung development w/out associated vasc anomaly. Bronchial atresia typically diagnosed later in life postulated to represent previously undiagnosed CLE. results in progressive overinflation of one or more lobes of a neonate's lung.
What other abnormalities are assoc. with CDH?
Malrotation (95%) Lung hypoplasia Neural tube defects
How is pulmonary edema most commonly presented on CT?
Most commonly associated with ground glass opacities (defined as increased density of pulmonary parenchyma without obscuration of vascular borders), and thickening of interlobular septa.
What is the radiographic presentation of most neonatal pneumonia cases?
Most pneumonia produce patchy asymmetric opacities and hyperinflation. Most common abnormality was bilateral alveolar opacities in 77% of cases. In one-third of the patients, the alveolar opacities were extensive with numerous air bronchograms. A pattern of radiographic abnormalities similar to transient tachypnea of the newborn was found in 17% of cases, and RDS-like picture was found in 13%.
How do viral lower respiratory infections present on imaging?
Over-inflation: low position of diaphragms, elevation of the sternum and flattening of the diaphragms on the lateral view Central interstitial opacities with peribronchial cuffing, reticular markings Unequal aeration - atelectasis of variable extent and regions of overinflation Air-space opacities are not uncommon Pleural effusion: uncommon, small
How does alveolar pulmonary edema develop and what is the appearance on radiographs?
Pressures of at least 25 mm Hg, but more often over 30 mm Hg. Earliest stages opacities may be small and nodular. With progressive alveolar filling, the chest radiograph pattern is of air-space consolidation, with dense or poorly defined pulmonary opacity. The pattern is more often symmetrical, but can be asymmetric or unilateral, especially if there is underlying pulmonary disease and uneven distribution of pulmonary blood flow.
HOw is arterial of CPAM supplied and how is this contrasted with sequestration?
Pulmonary circulation in CPAM Systemic circulation in sequestration
What are the "air block complications" of RDS/SDD?
Pulmonary interstitial emphysema (PIE), Pneumomediastinum Pneumopericardium Pneumothorax Extrathoracic soft tissue/ intravascular air
When does interstitial pulmonary edema develop (pressures) and how does it present on radiograph?
Pulmonary vein pressures of 18 mm Hg and higher Distributed in the perivascular sheaths, bronchial walls, interlobular septa, and subpleural space. Poor definition of pulmonary vessels, peribronchial thickening, increased reticular interstitial lung markings, subpleural fluid and the appearance of Kerley Kerley B lines represent fluid in the interlobular septa and are thin, dense horizontal lines seen best in the lung bases, extending to the pleural surfaces. Kerley A lines are straight, oblique, thin white lines that represent fluid in the interlobular septa of the upper lobes. Kerley C lines are the reticular pattern seen in the lung bases, thought to represent superimposition of Kerley B lines
What is Scimitar syndrome?
Represents partially anamolous venous return from right lower lobe pulmonary veins into either the right atrium or IVC.
What is the differential diagnosis for diffuse consilidation or diffuse granularity with air bronchograms seen on chest x-ray of a newborn?
Respiratory distress syndrome/SDD: Differential diagnosis includes immature lung, retained fetal lung fluid (TTN), pneumonia, CHF, and pulmonary hemorrhage. The absence of pleural effusion helps differentiate this disease from pneumonia.
What may cause the "air block complications" of RDS/SDD and what is the pathophysiology?
Result of rupture of damaged noncompliant alveoli. The air dissects through the perivascular interstitum and lymphatics, producing interstitial emphysema. Leak of air from the interstium and lymphatics to the mediastinum and subsequently to the pleura can develop, resulting in pneumothorax and pneumomediastinum.
What is Respiratory distress syndrome in the newborn and who is at risk?
SDD is the most common cause of respiratory distress in newborn. It mostly affects premature babies under 36 weeks of age (under 2.5 kg in weight). Other risk factors for development of SDD include maternal diabetes, maternal/fetal hemorrhage and multiple gestations. Decreased Lecithin/ Sphingomyeline ratio in amniotic fluids indicates increased risk of SDD development.
What are the types of CPAM and what is most closely associated with prognosis? What are those with CPAM predisposed to? What is usual recommendation for management?
Size of lesion largely determines prognosis.
What is most common bacterial PNA pathogen in normal children? CF/bronchiectasis?
Strep pneumo, H. influenza (declined) CF/bronchiectasis: Pseudomonas, H. flu, aspergillus.
How is Scimitar syndrome different than total anomalous pulmonary venous return?
TAPVR is when all four pulmonary veins return blood to the right atrium, and an obligate right-to-let shunt is necessary for survival.
What are CT findings of chronic lung disease of newborn or bronchopulmonary dysplasia of the newborn?
The CT manifestations of CLD/BPD include: multifocal areas of hyperinflation, well-defined linear opacities, decreased bronchus-to-pulmonary artery diameter ratios, and triangular subpleural opacities.
What are the histopathologic changes in RDS of the newborn?
The histopathologic changes consist of alveolar collapse, interstitial thickening, epithelial injury and bronchiolar distension. Proteinacous exudate (hyaline membranes), which is composed of necrotic cells and fibrin, is usually seen by 12-24 hours.
What causes respiratory distress syndrome in newborn?
The pathophysiologic cause of this disease is hypoventilation secondary to decreased surfactant production by immature type II alveolar cell. Surfactant production starts in week 24 of gestation and increases over the following weeks. Surfactant aids in lowering the alveolar surface tension and preventing atelectasis.
What is the radiographic pattern of transient tachypnea of the newborn?
The pattern of involvement changes from reticulogranular to interstitial. Normalization of the lung occurs from the periphery and the apices to the center the bases. This entity cannot be diffrentiated from aspiration of clear amniotic fluid.
What is treatment of Chronic lung disease of the newborn?
Treatment is supportive with oxygen, lasix and steroids.
How does radiograph present and change with CDH?
Typically fluid or solid looking bowel at birth in chest and shortly after turns to air filled bowel.
What does CLE usually involve and what is the typical pathophysiology of the disease? Tx?
Upper and middle lobes Initially fluid filled then radiolucent as fluid clears. Hyperexpansion can exert mass effect on surr. struc. Involved lobe may herniate across midline. Do not mistake for pneumothorax, chest tube will incr. distress. Bronchial obstruction can be cartilage causing a "ball-valve" effect letting air in and not out. Tx: Lobar lung resection.
What is most common cause overall of PNA in children?
Viral: RSV, influenza, parainfluenza, adeno
What is Wilson-Mikity-syndrome?
WMS is controversial uncommon cause of respiratory distress, where changes of CLD/BPD appear in an infant with no history of mechanical ventilation. The radiographic changes are similar to bronchopulmonary dysplasia. Unlike patients with bronchopulmonary dysplasia survivors of WMS have a good prognosis.
What is the radiological differential diagnosis for chronic lung disease/bronchopulmonary dysplasia in the newborn?
Wilson-Mikity-syndrome (WMS) Congenital pulmonary lymphangiectasia Neonatal tuberculosis Cystic fibrosis Hamman-Rich-syndrome.
What is the most common cause of CLE?
bronchomalacia - airway collapse in expiration leading to hyperinflation. CT can be used to find bronchial obstruction which is found in 50% of cases. Bronchial obstruction can be cartilage causing a "ball-valve" effect letting air in and not out.
When is bronch atresia usually diagnosed and related to?
incidentally in adulthood. CLE
What is bronchial atresia? area most commonly affected?
interruption of a bronchial branch with assoc. distal mucus impaction and hyperinflation. LUL
Waht is key imaging finding of sequestration?
systemic arterial vessel, can be seen by doppler on US prenatally, or by CTA or MRA postnatally.
