Affiliations: Department of Pediatric Neurology & Research
Center, Shahid Beheshti Medical University, Tehran, Iran
Note: [] Correspondence: Parvaneh Karimzadeh, MD, Department of Pediatric
Neurology, Shahid Beheshti Medical University, Tehran, Iran. Tel.: +98 21
22909559; Fax: +98 21 22909559; E-mail: pkarimzadeh@yahoo.com
Abstract: Benign idiopathic external hydrocephalus (BIEH) is an age dependent,
self-limited disorder with uncertain etiology. In this study, we aimed at
confirming the benign nature of this disease, focusing on avoidance of
unnecessary surgical intervention, relation to benign familial macrocephaly and
prevention of head trauma. In Mofid children's hospital, between September 2005
and September 2007, 20 infants, aged less than 1 year of age, were diagnosed
with BIEH, on the basis of macrocephaly and brain computerized tomography (CT)
scan findings, which all infants underwent at the beginning of the study; the
results revealed a large subarachnoid space. These infants were studied,
keeping in mind familial megalencephaly, birth history, head growth,
developmental prognosis and development of subdural hematoma. All children were
followed prospectively for 12 months. For all infants, CT scans were repeated
after 6 and 12 months. There were 14 (70%) boys and six (30%) girls; of
these 20 infants, 18 (90%) infants showed variable degrees of mild gross
motor developmental delay, while two (10%) had normal development. In all
infants, the head circumference was greater than the 90th percentile; 17 of
the fathers also had macrocephaly. After 12 months of follow up, all the
infants were observed to be developing normally. One infant was found to have
frontal subdural hematoma in association with prominent extracerebral
cerebrospinal fluid spaces with no history of major trauma or risk factors for
child abuse. CT scans, repeated after 12 months, showed resolution of the
process in 14 (70%) cases, improvement in five (25%) and no change in one
(5%). Considering that at the initiation of our study, 90% of infants had
variable degrees of mild gross motor developmental delay, and in follow up, all
the infants were developing normally, it can be concluded that BIEH is a
benign, self-limited condition that resolves without treatment and is closely
related to benign familial macrocephaly. Finally suggest idiopathic external
hydrocephalus could rarely predispose to the development of subdural hematoma
with minimal or no trauma.
