Wester K. Two Infant Boys Misdiagnosed as "Shaken
Baby" and Their Twin Sisters: A Cautionary Tale. Pediatr Neurol. 2019
Aug;97:3-11.
BEH [benign external hydrocephalus] may, however, be associated with cognitive problems 319
or have considerably more severe consequences, including a predisposition for
subdural hematomas (SDHs). This predisposition for SDH does not appear to be
well-understood by many of the physicians who deal with child abuse. Moreover,
the scientific evidence supporting a causal connection between nonaccidental
trauma and SDH in infants is at best scant.
This article describes two pairs of dizygotic twins with
nearly identical histories. Both twin pairs were born preterm just three weeks
apart; each pair consisted of a boy and a girl, and most importantly, the boys,
but not the girls, developed symptoms of increased intracranial pressure (ICP).
All the children were diagnosed with wide subdural-blood-containing fluid
collections, mainly over the frontal lobes, and medical expert witnesses told
the court that all four children had been subjected to violent shaking. As a consequence
one parent was sentenced to 1.5 years in jail and all four children were taken
from their biological parents and raised in foster homes for more than three
years until appeal courts decided in favor of the parents.
These children are by no means unique, but they may serve to
illustrate some important points concerning BEH and “shaken baby syndrome"
or abusive head trauma, including some striking epidemiologic similarities. In
addition to documenting these four children, this contribution reviews the
literature on the shaken baby syndrome or abusive head trauma with an emphasis
on the possibility that some infants with BEH might be mistaken for shaken baby
syndrome....
Boy1
Computed tomography (CT) the next day showed fluid
collections in widely enlarged subdural spaces, especially in the frontal
region, with higher density than cerebrospinal fluid (CSF), but only a few,
minor acute blood clots. The initial radiological description listed external
hydrocephalus as a diagnosis; this was later abandoned, and the CT was finally
described as showing a “large subdural hematoma,” SDH.
Child abuse was suspected. A total skeleton x-ray evaluation
revealed no fractures; he had no bruises or subcutaneous hematomas.
Ophthalmoscopy showed bilateral, extensive retinal hemorrhages (RH)...
Based on the radiological description of “a large subdural
hematoma” and bilateral retinal hemorrhages (RH), the case was reported to the
child protection team and the police, followed by a charge of child abuse
against his father. The medical experts in the lower court (forensic medicine,
ophthalmology, and pediatrics) testified in favor of child abuse, disregarding
the perioperative finding of only clear fluid without visible blood. The father
was sentenced to 1.5 years in jail but appealed the verdict. Both twins were
taken from the parents and raised in foster homes for the next three years.
The boy had sustained severe brain injury; the follow-up MRI
was described as follows: “ The restricted diffusion as seen here is a finding
that in nearly all cases can be taken as a sign of severe lack of oxygen and an
early permanent brain damage ” (the author's translation from Norwegian). The
boy is permanently vegetative...
The appeal court
In the appeal court, the author was appointed expert witness
in addition to those from the primary court, who still favored the abuse
explanation. The father was found not guilty, as the court accepted BEH and
associated complications as a more likely cause of the condition than physical
abuse...
Boy 2
He had no bruises or other external indications of injury.
On the third day, MRI and CT scans were performed. The CT scan showed “ a
subdural haematoma/fluid collection with a definitely higher density than CSF,
but lower density than cerebral cortex (hypodense/isodense) with hyperdense
stripes in the frontal subdural space, probably representing fresh blood in the
subdural space ” (the author's translation). The MRI scan was interpreted as
showing the same, with the age of the hematomas estimated as two to three days
to a few weeks. Twelve plain skeleton X-rays revealed no fractures.
Fundoscopy disclosed multiple RH in several layers of retina
in one eye but only two minor peripheral bleedings in the other, the conclusion
being “ findings compatible with retinal haemorrhages as seen in the
shaken-baby syndrome, although it is atypical that the extent of bleedings is
so different in the two eyes ” (the author's translation).
Child protection authorities and police were notified, and
both infants were routinely placed in a foster home, where they remained for
the next three years.
The appeal court
The police found it difficult to prove physical abuse and
rested the case. The child protection authorities, however, insisted on keeping
the children separated from their parents. A lower court had decided in favor
of the parents, but the child protection authorities appealed that decision and
delayed the transfer of the children back to their parents for another 16
months. The appeal trial was almost identical to the one described above, with
almost the same set of expert witnesses, including the present author. The
court decided in favor of the biological parents, and after more than three
years, the children were reunited with their parents.
This report describes two pairs of three-month-old premature
dizygotic twins who were separated from their biological parents for three
years under the assumption that they had been subjected to vigorous shaking.
This assumption was based solely on neuroimaging findings of extracerebral or
subdural fluid collections described as containing chronic hematomas and small
amounts of fresh blood. In addition, the boys, but not the girls, had dramatic
symptom debuts and were found to have RH described as compatible with
nonaccidental head injury caused by shaking. None of the twins had any sign of
impact to the head or any extracranial finding indicating violence. Duhaime et
al. stated in 1987 that impact is required to cause the findings of the triad.
In the author's opinion, all four infants exhibited
extracerebral fluid collections compatible with external hydrocephalus, as
defined by several authors. Most likely, their BEH condition had been
complicated by spontaneous bleeding or oozing of blood products into the
subdural space; BEH is known to predispose for spontaneous subdural bleedings
in infants, and this predisposition can be a pitfall in the diagnosis of
abusive head trauma.
Shaken baby syndrome and lack of medical evidence
These infants were diagnosed as having been shaken with the
most serious consequences for their families. It therefore seems appropriate to
analyze the quality of medical evidence behind the widely accepted notion that
a triad consisting of SDH(s), RH, and encephalopathy can be used to prove a
criminal act—shaking. As in other countries, in Norway guilt has to be proven
beyond reasonable doubt. The solidity of the triad as proof of a criminal act
must therefore not be doubted.
It is difficult to find scientific evidence above level 3
for a causal relationship between the triad and violent shaking, as also
concluded after an extensive earlier review. 41 A more recent review, based on
thousands of articles, concluded as follows: “ There is limited scientific
evidence that the triad and therefore its components can be associated with
traumatic shaking (low quality evidence). There is insufficient scientific
evidence on which to assess the diagnostic accuracy of the triad in identifying
traumatic shaking (very low quality evidence) ”. No study based on observed
shaking could be identified. Only two studies in the literature were found to
be based on confessed shaking; these confessions came during police custody or
judicial investigations, weeks to months after the diagnosis. Confessions
obtained under such circumstances are known to be encumbered with
uncertainties. These conclusions
underline the importance of considering alternative etiologies for the triad
and its findings.
Subdural hematomas will inevitably raise suspicion of child
abuse; SDH may, however, also appear spontaneously in infants, often
precipitated by one of two congenital conditions, namely, arachnoid cysts or
BEH. Several mechanisms may explain why external hydrocephalus predisposes for
SDH. To me as a neurosurgeon, the most likely is leakage of small amounts of
blood from where the bridging veins enter the dura. It is a common
intraoperative observation that even minor manipulations of normal bridging
veins during a craniotomy may cause such leakage. In external hydrocephalus,
these veins may ooze blood spontaneously just because they are stretched.
Subdural hematomas also occur in newborns, especially in preterm
deliveries and twins; our twins were born four to five weeks preterm. Subdural
hematomas occur more frequently after vaginal delivery than after a planned
Caesarean section and even more frequently after emergency Caesarean sections
and forceps or vacuum-assisted deliveries. These subdural blood collections may
gradually develop into larger hematomas over time. There are factors in old
hematomas that may induce neovascularization in the parietal hematoma membrane,
and these pathologic vessels bleed easily. Other factors disturb normal
coagulation in subdural blood collections.
Male preponderance: Our group has recently found a male
preponderance of 86% in a population-based epidemiologic study of BEH. Others
have documnted a similarly high male preponderance, even as early as in 1944 by
Ingraham and Matson.
Adamsbaum et al. and Vinchon et al. also reported male
preponderance in their abuse cases, 76% and 64%, respectively. Pooled together,
these two studies show a male preponderance of 73%. A male preponderance has
also been demonstrated in most published series on shaken baby syndrome or
abusive head trauma. The large number (157) of infants in the two studies above
renders it unlikely that this male dominance is coincidental. Moreover, in a
national register study comprising 306 infants with SDHs, we have recently
demonstrated that even in this cohort, there was a clear overrepresentation of
males...
To the present author, the twins' MRI and CT scans carry no
resemblance to an acutely acquired traumatic hematoma. In this context, it is
of interest that the Adamsbaum et al. 44 report included a CT scan (see their
Fig 1) of an allegedly shaken infant; the scan appears to show the exact
features of external hydrocephalus, as defined by Maytal et al.: slightly
widened lateral ventricles, a large extracerebral space, and widening of the
frontal interhemispheric fissure. Girard et al. provided a detailed discussion
of external hydrocephalus as a differential diagnosis to abusive head trauma.
The only plausible explanation of the combination of an
increased or rapidly growing HC, increased extracerebral fluid, and enlarged
ventricles is that there is an increased ICP equally distributed within the
intracranial compartments, in both the extracerebral space and the ventricles.
A traumatic acute or chronic SDH would normally compress the brain, including
the ventricles, and if unilateral, would cause asymmetry of the ventricles and
a midline shift. These characteristic features were absent in our twins and
surprisingly, also in other children published as victims of shaking...
Bilateral, extensive
bleeding in several retinal layers has been regarded as a key feature of
abusive head trauma. However, RH may not be pathognomonic for abusive head
traumas; they can also be seen in infants not related to abuse, e.g., in a
large number of healthy newborns, in infants with “macrocephaly,” after
“high-risk” deliveries, following acute life-threatening events, and after
cardiopulmonary resuscitation. RHs have also been documented in premature
infants; contrary to the rapid resolution of the bleeding one usually sees in
most newborns, the bleeding in preterms tend to be long lasting.
As for the rest of the triad, there is no high-quality
evidence that proves a causal relationship between retinal bleedings and
violent shaking. The problem lies again in the lack of objective proofs of
shaking...
My concern in this report is that many infants appear to be
diagnosed as shaken babies without any clear signs of an inflicted trauma
(impact). The scientifically weak documentation of a causal relationship
between the triad and the criminal act of violent shaking without impact cannot
be used as judicial evidence for child abuse, beyond reasonable doubt.
When suspecting the shaken baby syndrome or abusive head
trauma, external hydrocephalus should always be ruled out as a possible
alternative diagnosis, as this condition may have medical findings compatible
with those claimed to prove violent shaking. Unfortunately, many physicians who
deal with child abuse seem unfamiliar with the manifestations of benign
external hydrocephalus in children.
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