Kt. Nixon et al., DELAYED INTRACRANIAL HEMORRHAGE IN CHILDREN AFTER SUBOCCIPITAL CRANIECTOMY, American journal of roentgenology, 163(4), 1994, pp. 897-900
OBJECTIVE. The purpose of this study was to report the clinical and im
aging findings of seven children who developed extraaxial, intracrania
l hemorrhage 3-12 years after suboccipital craniectomy for neoplasia.
We attempt to explain the hemorrhages based on a previously reported h
ypothesis of neomembrane formation associated with dural substitutes u
sed to repair large dural defects. MATERIALS AND METHODS. Clinical cha
rts (seven patients), surgical and pathologic findings (four patients)
, and imaging studies (CT scans and MR images in four; CT scans, MR im
ages, and angiograms in one; and CT scans only in two patients) were r
eviewed retrospectively. Hemorrhage occurred 3-12 years after suboccip
ital craniectomy for tumor (ependymoma in two, medulloblastoma in thre
e, astrocytoma in one, and ganglioglioma in one). Silastic dural subst
itute was used to repair the surgical wound in six cases and human dur
al graft in one case. Hematomas were spontaneous in four and occurred
after minor head trauma in three. Four patients had multiple hemorrhag
ic episodes. RESULTS. CT scans and MR images showed acute extraaxial h
emorrhages at the craniectomy site without contiguous residual or recu
rrent neoplasia in all patients. No intraaxial or intratumoral hemorrh
age was detected. Findings on cerebral angiograms in one patient were
normal. Four patients underwent surgical exploration of the hematoma a
nd craniectomy site; no macroscopic source of bleeding was detected. T
he hematomas were not associated with recurrent tumor pathologically.
CONCLUSION. Delayed, benign extraaxial hematomas may occur in children
who have undergone craniectomy for tumors of the posterior fossa and
have had dural substitute used to repair large defects. Fragile vessel
s associated with neomembranes have been proposed as the source of hem
orrhage.