Pediatric RadiologyPediatric RadiologyPediatric RadiologyPediatric Radiology

Indications for Pediatric Radiographic Examination

• History• Will the imaging give you any added

clinical data?• Benefits vs. risk

– American College of Radiology (ACR) Appropriateness Criteria available at www.acr.org

• All radiological exams carry risk• gonads• breast• thyroid• lung• Bone

The concept of ALARA (as low as reasonably achievable) should be

applied to all patients…

Radiation Exposure - Children

• Considerably more sensitive to radiation than adults

• Also have a longer life expectancy– a larger window of opportunity for

expressing radiation damage

Compared with a 40-year old, the same radiation dose given to a neonate is several times more likely

to produce a cancer over the patient’s lifetime

Retrieved 01-17-05 from http://www.cancer.gov/cancertopics/causes/radiation-risks-pediatric-CT

Never radiograph routinely!

• Will the results change my management?

• Will the study confirm my clinical suspicions?

• Is this the appropriate study for what I’m trying to confirm?

Technical Issues

• Instructional compliance• Motion

– The child should be stabilized by the parent

• Recumbent radiographs a necessity in young children– acute fractures

uprightupright recumbentrecumbent

• Must know the normal radiographic appearance at each age for accurate interpretation– Atlas of normal developmental anatomy– Consult a DACCBR?

• Chiropractic line analysis– Children are not small adults…

Does the technique recognize this?

Radiographic Interpretation

Normal Pediatric Variants

• Pseudosubluxation• Pseudospread of C1 on C2• ADI space• Absence of cervical lordosis• Normal appearance of ossification

centers and epiphyses

Pseudosubluxation

• Normal variant• Occurs most commonly at C2/C3

– 40% of normal children <7 years of age– 24% of those under 16 years

• Also occurs at C3/C4– 20% of those <7 years; 9% <16 years

http://www.medcyclopaedia.com/library/topics/volume_vii/p/pseudosubluxation.aspx

• A line drawn connecting the anterior cortices of the spinous processes of C1 and C3 should intersect or lie within 1 mm of the anterior cortex of the spinous process of C2

• If C2 is >2mm off of this line = true injury

http://www.uth.tmc.edu/radiology/test/er_primer/spine/images/csp40.html

http://www.medcyclopaedia.com/library/topics/volume_vii/p/pseudosubluxation.aspx

Swischuk's line distinguishes pseudosubluxation from pathological subluxation

Pseudospread of C1 on C2

• Normal variant• Lateral mass displacement relative

to the dens – Up to 6mm is common <4 yoa– Can be seen up to 7 yoa

Lustrin ES, Karakas SP, Ortiz AO et al. Pediatric Cervical Spine: Normal Anatomy, Variants and Trauma. RadioGraphics 2003; 23:539-60.

Pseudospread of C1 on C2

Lustrin ES, Karakas SP, Ortiz AO et al. Pediatric Cervical Spine: Normal Anatomy, Variants and Trauma. RadioGraphics 2003; 23:539-60.

Other Common Variants• ADI space

– Maximum of 4mm (new literature) in children

• Absence of cervical lordosis– Can be seen in children up to 16 yoa

• Oval/wedge shaped vertebrae are normal– Not to be confused with compression fx

• Normal appearance of ossification centers and epiphyses can simulate fractures…

Lustrin ES, Karakas SP, Ortiz AO et al. Pediatric Cervical Spine: Normal Anatomy, Variants and Trauma. RadioGraphics 2003; 23:539-60.

Copyright ©Radiological Society of North America, 2003

Lustrin, E. S. et al. Radiographics 2003;23:539-560

Figure 1b

synchondrosis

Copyright ©Radiological Society of North America, 2003

Lustrin, E. S. et al. Radiographics 2003;23:539-560

Figure 4

• The spaces between the sacral segments are synchondroses composed of fibrocartilage, not discs– Bone starts to be deposited in the

fibrocartilage starting at puberty

*They do not move like vertebrae…

Gray, Henry. Anatomy of the Human Body. Philadelphia: Lea & Febiger, 1918; Bartleby.com, 2000. www.bartleby.com/107/. [January 20, 2006].

http://www.bio.psu.edu/people/faculty/strauss/anatomy/skel/sacrum2.htm

Where is the anomaly?

Os Odontoideum

• Results from injury at the odontoid synchondrosis

• Flexion/extension radiographs• Neurological deficit?• Neurologist/orthopedist consult

Epiphyseal Plate Injuries

Salter-Harris Classification

http://xray.20m.com/photo4.html

Child Abuse

• Physical, sexual, nutritional abuse or neglect

Must report to appropriate agency!

– Remain professional and objective– Be non-judgemental toward parents

Radiography plays an important part in documenting physical abuse

• Technical considerations– reveal soft tissues well– high detail radiographs – sectionals, not “babygram”

Battered child syndrome

• Metaphyseal “corner” fractures• Multiple fractures at various stages of

healing• Ribs, scapula• Head injuries

– Skull fx, subdural hematoma, shearing injuries*MC cause of death + disability in child abuse

• Soft tissue swelling and injuries – i.e. contusions, burns, etc.

Oblique fractureOblique fracture

Periosteal reactionPeriosteal reaction

Metaphyseal corner fxMetaphyseal corner fx

Linear skull fracturesLinear skull fractures

Multiple metacarpal Multiple metacarpal fracturesfractures

Rib fractures– Especially posterior aspect

Hx: 2 yo with vomiting and diarrhea

Initial abdomen and chest films normal

Increased WBC

Elevated ESR

Findings:

-decreased disc height

-abnormal signal in two adjacent VB

-paraspinal mass

Dx: discitis

Swischuk LE. Vomiting, diarrhea and--oh! oh! what is that? Pediatr Emerg Care. 2004 Jan;20(1):54-6

Spinal infectionDiscitis• A common problem in infants• MC lumbar region, lower thoracics

• S/S: back pain (often can’t directly communicate) and difficulty walking or limping

Therefore, when one has exhausted all of the more common causes of limping, one should look to the lower thoracic and lumbar spine regions for the presence of discitis.

Swischuk LE. Vomiting, diarrhea and--oh! oh! what is that? Pediatr Emerg Care. 2004 Jan;20(1):54-6