Abusive Head Trauma

KEY FACTS

TERMINOLOGY

• Intentionally inflicted injury; abusive head trauma, inflicted

head injury, nonaccidental head injury

IMAGING

• Plays key role in early diagnosis

○ Disparate brain injuries relative to proffered history

• Skeletal survey, NECT as initial primary imaging tools

○ Detection/characterization of intracranial hemorrhage

○ Detection/characterization of fractures

• MR

○ Delayed (24-72 hours) for detection of parenchymal

injuries, demonstration of unexplained, different-aged

subdural hemorrhages (SDHs)

– Use T1WI, T2WI, T2*/SWI (best sequence varies with

SDH age)

– DWI key for identification of parenchymal insult

– Use T1W1 C+ to detect subdural membranes of

chronic SDH

– Sagittal/coronal best for small peritentorial SDHs

PATHOLOGY

• Direct impact injury

○ Skull fractures

○ Underlying brain injury

• Violent "to and fro" shaking

○ Diffusely distributed subdural hematomas

○ Cortical contusions, axonal injury, parenchymal

lacerations

• Ischemic injury

○ Global hypoxic brain injury

○ Territorial infarcts

○ Excitotoxic edema

CLINICAL ISSUES

• Most common cause of traumatic death in infants

• Signs of trauma (e.g., Battle sign, raccoon eyes) may be

present but often are not

(Left) Coronal graphic of

abusive head trauma (AHT)

shows an acute subdural

hemorrhage (SDH) over the

right hemisphere ﬈ and a

smaller left SDH ﬉ with

hematocrit effect producing

layering of blood products ﬊.

Other injuries (traumatic SAH,

cortical contusions) are

illustrated and are common in

AHT. (Right) Funduscopic

examination in an infant with

suspected AHT shows multiple

retinal hemorrhages ﬈.

Retinal hemorrhages are

present in up to 95% of AHT

cases.

(Left) Axial NECT in suspected

AHT shows varied attenuation

SDHs with right low

attenuation st, bilateral high

attenuation ſt SDHs. The

diffuse edema involves almost

the entire left hemisphere ﬇.

(Right) Axial T1WI MR in an

infant with AHT shows

subacute right SDH ſt

extending into the

interhemispheric fissure and a

more chronic-appearing left

subdural collection (chronic

SDH vs. hygroma) ﬇.

Trauma, and Stroke

Brain: Pathology-Based Diagnoses: Malformations,

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