MRI is preferred over CT because it provides more information and does not involve ionizing radiation (X-rays). Features on CT 1) and MRI 2):
There remains a lack of consensus about the role of individual imaging modalities in characterizing specific features of the condition and predicting the success of CSF shunting. Variability of clinical presentation and imperfect responsiveness to shunting are obstacles to the application of novel imaging techniques. Few studies have sought to interpret imaging findings in the context of theories of NPH pathogenesis 3).
Although attempts at predictive methodology, such as highvelocity aqueductal flow rate measurement on MRI, have achieved widespread acceptance in clinical practice, there is no Class I evidence (only 1 Class II study and 2 Class III studies) available to support this 4).