Introduction: For subarachnomegaly in infants with enlarged external and internal CSF spaces clear treatment decisions, such as observation or ventriculo-peritoneal (VP) shunting, are still lacking. The aim of this study is to measure intracranial pressure (ICP) in these patients to elucidate treatment necessity.
Materials and methods: Seven children presenting with macrocephaly, moderately enlarged ventricles, and subarachnoid spaces on magnetic resonance imaging (MRI) without neurological deficits or other CSF-associated pathological conditions were enrolled. Continuous ICP recording was conducted using an external ventricular drain. Data recordings during overnight measurements were analyzed offline to calculate baseline, mean ICP values, and a histogram distribution.
Results: Mean age at enrollment was 9.4 months (2-22 months). ICP monitoring was conducted for 2.7 ± 1.1 nights (range 2-5 nights) and revealed baseline values above 10 mmHg in three patients, who went on to receive a VP shunt. One patient with average values over 10 mmHg also underwent VP shunting. Three patients displayed both baseline and average ICP values of less than 10 mmHg. Observational management was chosen for this subgroup. Comparing shunted versus the non-shunted group in a histogram analysis the percentages of recorded ICP values above 8, 10, and 15 mmHg were significantly different (p < 0.05).
Conclusion: Subarachnomegaly in infants remains a dilemma to the treating neurosurgeon. Risks and benefits of observational management options need to be weighed against those of VP shunting. Continuous ICP monitoring may help to identify patients who may potentially benefit from the surgical treatment option.