pediatric radiology

Question 1

modalities

Answer 1

• sonography
• x-ray
• CT
• scintigraphy
• MRI

Question 2

x-ray

Answer 2

• radiation
• sensitivity to radiation: red marrow, gonads
• dosis cumulation
• no routine investigation
• indications, special technique

B- beam
A- artefacts
S- shielding
I- immobilisation & indications
C- collimation
S- structures

Question 3

contrast material in x-ray

Answer 3

• with modern CM, seldom side effects
• newborn: CM of low osmolality (dehydration)
• air as negative CM
• dynamic investigation: only with fluoroscopy

Question 4

ultrasound

Answer 4

• non-invasive, no side effects, no contraindications
• fast, repeatable
• sections in every direction
• real time: motion
• vessels
• cheap
• limitations: bones, air, depends on operator
• different sonoanatomy in adults, children, newborns

Question 5

head sonography

Answer 5

• through the fontanella until 8-10 months of life
• 5 MHZ convex transducer
• coronal & sagittal sections
• width of ventricles, possible hemorrhage
• in the brain: hemorrhage, cysts, calcifications
• congenital anomalies
• indications:
• prematurity
• hypoxic injury
• neurological symptoms, convulsions
• sepsis
• suspected congenital anomaly

Question 6

causes of hydrocephalus

Answer 6

• hemorrhage

- infection

Question 7

intraventricular hemorrhage (IVH) in newborn

Answer 7

• grade 1: subependymal h.
• grade 2: hemorrhage in the ventricles, without ydrocephalus
• grade 3: IVH + hydrocephalus
• grade 4: parenchymal hemorrhage

Question 8

spinal sonography

Answer 8

• 7-10 MHz linear transducer
• through the cartilage of the posterior arch
• anomalies, intraspinal masses
• tethered cord: spinal dysraphy, conus too deep, fixation to an intraspinal lipoma, paresis, incotinence

Question 9

hip sonography

Answer 9

• screening for hip dysplasia
• 6 weeks - 6 months
• cartilaginous femoral head
• Graf’s method:
• standardized
• measurement of angles
• state of development
• therapy

Question 10

scintigraphy (nuclear medicine)

Answer 10

• ionising radiation (mostly gamma-ray) -> low dose
• function
• no morphology
• kidneys
• bones
• special:
• MIBG: neuroblastoma
• GERD
• VUR (vesicoureteral reflux)

Question 11

CT

Answer 11

• need sedation in children
• rdiation: 300-400 x chest x-ray
• IV contrast material
• indications:
• CNS: hemorrhage, trauma
• chest: lungs, airways, chest wall
• abdomen
• bones: tumor, trauma

Question 12

MRI

Answer 12

• no radiation
• no side effects
• precise anatomy in each direction
• +/- CM
• time consuming
• narcosis, sedation
• claustrophobia
• expensive
• metallic implantation material can be contraindicated
• indications:
• CNS
• heart & vessels
• MSK, bone marrow
• abdomen
• mediastinum
• MR urography
• MR angiography
• MRCP

Question 13

fetal MRI

Answer 13

• if sonography fails
• planned postnatal interventions, or need for abortion
• congenital anomalies
• early rupture of membranes
• lack of growth
• twins
• known genetic disorder
• routine fetal MRI: 20-30 min
• moving artefacts
• claustrophobia
• no MRI in the 1st trimester

Question 14

normal thymic shadow

Answer 14

• can appear as a mediastinal mass in children
• sonography: homogenous structure in the anterior mediastinum
• visible on CXR until 3y of age
• variation in form and size

Question 15

respiratory distress (IRDS)

Answer 15

• premies
• surfactant deficiency
• alveolar atelectasis
• grade I - IV
• 6-12 hours after birth

Question 16

foreign body aspiration

Answer 16

• most FBs are radiolucent
• expiration: overdistension of the affected area
• fluoroscopy: mediastinal shift to the normal side in expiration
• urgent bronchoscopy

Question 17

VCUG

Answer 17

• voiding cystoureterography
• fluoroscopy
• diluted CM via catheter into the badder
• prophylaxis for reflux is needed
• CE VCUG:
• US-CM
• microbubbles: 1-10 micrometer
• reflux in the filling phase or under micturition

Question 18

MR - urography

Answer 18

1. PROs:
   - no radiation
   - no CM -> T2W: fluids, nice anatomy
   - with CM -> T1W: dynamic - kidney function
2. CONs:
   - time consuming
   - expensive
   - sedation

Question 19

newborn with ileus

Answer 19

• air as CM
• too little: proximal obstruction
• too much: distal obstruction
• double bubble: duodenal atresia

Question 20

Hirschsprung’s disease

Answer 20

• no ganglia in the colon (aganglionosis)
• constipation since birth
• abnormal distension
• barium enema, biopsy
• surgery

Question 21

epiphyseal fractures

Answer 21

• under 16y: 6-18% of all extremity fractures
• complications: growth anomalies in 25-33%
• Salter-Harris classification of growth plate injuries ( I-V)

Question 22

Rickets

Answer 22

• vitamin D deficiency
• failure in bone mineralization
• hyperplastic non-calcified cartilage

Question 23

osteomyelitis

Answer 23

• hematogenous infection
• Staph. aureus (70-90%)
• first in the bone marrow of the metaphysis
• < 18 mo -> anastomosis between meta- and epi- physis
• later: growth plate is a barrier
• small children septic arthritis -> growth disturbances, deformities

Question 24

child abuse, battered child

Answer 24

• typical pattern of injuries
• metaphyseal fractures
• ribs, sternum, scapulae
• multiple fractures of different ages
• periosteal reaction, epiphyseolysis, complex skull fractures
• discrepancy between history and injury
• CNS an visceral injuries
• shaken baby (abusive head trauma)