Dear Editor:

We would like to thank Udayakumaran et al. for their interest in our article. We are in complete agreement with their comments regarding the physics that may contribute to this phenomenon. What was of interest to us in this case was that instead of herniation of the cerebral hemispheres (telencephalon), this child had isolated herniation of the diencephalon. One would have expected the usual pattern of trans-tentorial herniation as described in other cases.

As regards the management priorities listed, we promptly assessed for shunt malfunction on the initial presentation and hence his shunt was revised. Following the herniation, we immediately again assessed for shunt malfunction by aspirating CSF from the reservoir. CSF was easily aspirated at this time and, along with radiological findings, we deemed the shunt to be functioning. Ruling out shunt malfunction should definitely be the initial and most important management pearl in this scenario.

We opted for conservative management of the diencephalic herniation after having extensive discussion with parents and also carefully considering the child’s clinical condition at presentation, his past history and also taking into consideration his quality of life. We certainly agree that simultaneous shunting of both the ventricles and the posterior fossa cyst would be the most preferable treatment for the symptoms of over-drainage in any other patient as recommended.

Finally, flow-regulating valves have been shown to have fewer over-drainage complications than differential valve in infantile hydrocephalus [1]. Unique cases like ours are not only interesting but serve to highlight how we can update our management of such complicated cases in the future.