Cerebrospinal fluid dynamics study in communicating hydrocephalus

Vengalathur Ganesan Ramesh; Vidhya Narasimhan; Chandramouli Balasubramanian

doi:10.4103/1793-5482.145110

Cerebrospinal fluid dynamics study in communicating hydrocephalus

Asian J Neurosurg. 2017 Apr-Jun;12(2):153-158. doi: 10.4103/1793-5482.145110.

Authors

Vengalathur Ganesan Ramesh¹, Vidhya Narasimhan², Chandramouli Balasubramanian¹

Affiliations

¹ Department of Neurosurgery, Chettinad Superspeciality Hospital, Chettinad Health City, Kelambakkam, Tamil Nadu, India.
² Institute of Neurology, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India.

Abstract

Context: Communicating hydrocephalus often poses a challenge in diagnosis and management decisions.

Aims: The objective of this study is to measure the opening pressure (P_o), pressure volume index (PVI), and cerebrospinal fluid outflow resistance (R_out), in patients with communicating hydrocephalus using bolus lumbar injection method and to evaluate its diagnostic and prognostic value.

Materials and methods: The study was conducted in 50 patients with communicating hydrocephalus, including normal pressure hydrocephalus (NPH) (19), post-meningitic hydrocephalus (23) and post-traumatic hydrocephalus (8). An improvised bolus lumbar injection method [the Madras Institute of Neurology (MIN) method] was used.

Results: In the NPH Group, the CSF dynamics studies correlated well with the clinico-radiological classification. The prediction of shunt responsiveness by CSF dynamics studies correlated with good outcome in 87.5%. In the post-meningitic hydrocephalus group, the value of CSF dynamics studies in predicting patients needing shunt was 89.5%. The CSF dynamics studies detected patients who needed shunt earlier than clinical or radiological indications. In the post-traumatic hydrocephalus group, 62.5% of patients improved with the treatment based on CSF dynamics studies.

Conclusions: The improvised bolus lumbar injection method (MIN method) is a very simple test with fairly reliable and reproducible results. Study of CSF dynamics is a valuable tool in communicating hydrocephalus for confirmation of diagnosis and predicting shunt responsiveness. This is the first time that the value of CSF dynamics has been studied in patients with post-meningitic hydrocephalus. It was also useful for early selection of cases for shunting and for identifying patients with atrophic ventriculomegaly, thereby avoiding unnecessary shunt.

Keywords: Bolus lumbar injection test; cerebrospinal fluid dynamics study; cerebrospinal fluid outflow resistance; communicating hydrocephalus; normal pressure hydrocephalus; post-meningitic hydrocephalus.