SOPHOMORE PEDIATRIC CHEST

Remember in each case:

1. Proper technique - ability to see important landmarks.
2. Orientation of the film , i.e. left or right marked.
3. Good inspiratory effort without motion.
4. Recognize film artifacts.
5. Systematic approach in looking at films.
6. Pertinent clinical history.

Interpretation of films.

1. Normal Chest

   1. Trachea in midline or slight buckle to right at thoracic inlet.

   2. Thymus - large water dense mass in the superior mediastinum. Usually wavy contour. Bilobed but not always symmetrical.

   3. Heart - water dense seen usually with apex to left. Occupies about 50% of chest width at widest point. Aortic knob may be seen through thymus on left.

   4. Pulmonary vessels - hila seen best on lateral. Vessels extend to mid lung, tapering gradually.

   5. Lungs - uniformly aerated. Appear black on most films.

   6. Bony structures - ribs usually 10-12 well seen. Upper thoracic vertebral bodies, scapulae, and clavicles seen well.

   7. Diaphragms - right and left equal. Usually seen at level of 9-10 ribs.

2. Distressed Infants

   1. Congenital lobar emphysema

      1. Condition of progressive over-distention of a lobe producing atelectasis of adjacent lobes and a mediastinal shift.

      2. X-ray - may be quite lucent mimicking pneumothorax. Also may be water dense or fluid filled early.

      3. Usually a surgical emergency.

      4. Differential diagnoses includes adenomatoid malformation, bronchogenic cyst, hygroma.

   2. Chylothorax

      1. Cause of large pleural effusion in newborn, thought to be associated with birth trauma.

      2. X-ray - effusion is unilateral but may be right or left large

      3. Differential includes erthyroblastosis, congestive heart failure, renal disease.

      4. Treat with thoracentesis.

   3. Meconium aspiration

      1. Usually occurs with fetal distress. Infants are meconium stained at birth.

      2. Usually a chemical pneumonia due to swallowing amniotic fluid mixed with meconium.

      3. X-ray - patchy aeration of both lungs. Over-distention.

      4. Complication leads to air-block syndrome with pneumothorax or pulmonary hemorrhage.

      5. Differential - transient tachypnea, neonatal infection, lymphangiectasia.

      6. Usually responds to supportive therapy.

   4. Respiratory distress - hyaline membrane disease

      1. Condition that affects premature infants related to a

         deficiency of surface active agent surfactant.

      2. Infants are symptomatic immediately or soon after birth.

      3. X-ray - diffuse reticulogranular or ground glass appearance to lungs due to microatelectasis. Air bronchogram seen at lung bases. Pulmonary interstitial emphysema may develop with therapy.

      4. Complications - pneumothorax, bronchopulmonary dysplasia, persistent patent ductus with CHF.

   5. Neonatal pneumonia

      1. Occurs because of interuterine infection (i.e. cytomegalic inclusion virus) or shortly after birth.

      2. Virus can be principle cause although other organism such as strep, staph or E Coli. Common viral pneumonias include H. flu and herpes.

      3. X-ray - patchy infiltrate in perihilar area. May lead to diffuse involvement of entire lungs. Occasionally pleural effusion may occur.

      4. Complications - generalized sepsis or lung abscess may occur.

      5. Therapy - appropriate antibiotic along with oxygen and fluid support as needed.

   6. Tuberculosis

      1. May occur in newborns because of interuterine infection or may be acquired in infancy.

      2. Infants may not appear to have clinical disease despite postive cultures.

      3. X-ray - frequently shows adenopathy with peripheral patchy infiltrate. Infiltrate may be more extensive than clinically apparent. Foci of infection may calcify.

      4. Complication - dissemination either by bronchial route or hematogenous route to involve other organ systems (renal,cardiac, etc.). Miliary pattern.

   7. Esophageal atresia with or without tracheal fistula

      1. Common developmental disorder involving separation of the primitive foregut into trachea and esophagus.

      2. May present with gagging or aspiration during feeding. Failure to allow passage of nasal gastric tube.

      3. X-ray - dilated upper esophagus on PA and lateral films. Abdomen may be gasless if no fistula. Try not to use contrast

      4. Complication - pneumonia, failure to thrive. Frequently seen with other congenital anomalies involving spine, heart,kidneys, GI tract.

   8. Diaphragmatic hernia

      1. Usually due to embryonic defect in posterolateral portion of diaphragm. Left hemidiaphragm involved more than right.

      2. Infants usually asymptomatic at birth but develop progressive respiratory symptoms especially after feeding.

      3. X-ray - multiple lucencies in one side of chest with displacement of heart and mediastinum to opposite side. Abdomen is frequently scaphoid due to lack of bowel.

      4. Complications - respiratory embarrassment due to mass effect. Lungs may be hypoplastic developmentally.

      5. Surgery to repair defect.

   9. Masses

      1. Masses in chest due to tumor are usually benign, however neuroblastoma does occur frequently as a posterior mass. Teratomas or cystic hygromas present in anterior mediastinum.

      2. While displacement of the trachea and esophagus is not uncommon, these masses produce mild symptoms initially.

      3. X-ray- smooth or sharply defined mass displacing the trachea and extending into lungs. May contain calcium if teratoma. Hygromas may also be seen extending into neck in majority of cases.

      4. Complications - related to mass effect.

      5. Differential - pleural effusion, fluid filled lung cysts.

      6. Therapy- surgery.