BACKGROUND AND PURPOSE: Although neuroimaging plays an important role in the diagnosis of idiopathic normal pressure hydrocephalus, its predictive value for response to shunt surgery has not been established. The purpose of the current study was to identify neuroimaging markers that predict the shunt response of idiopathic normal pressure hydrocephalus. MATERIALS AND METHODS: Sixty patients with idiopathic normal pressure hydrocephalus underwent presurgical brain MR imaging and clinical evaluation before and 1 year after shunt surgery. The assessed MR imaging features included the Evans index, high-convexity tightness, Sylvian fissure dilation, callosal angle, focal enlargement of the cortical sulci, bumps in the lateral ventricular roof, and deep white matter and periventricular hyperintensities. The idiopathic normal pressure hydrocephalus grading scale total score was used as a primary clinical outcome measure. We used measures for individual symptoms (ie, the idiopathic normal pressure hydrocephalus grading scale subdomain scores, such as gait, cognitive, and urinary scores), the Timed Up and Go test, and the Mini-Mental State Examination as secondary clinical outcome measures. The relationships between presurgical neuroimaging features and postoperative clinical changes were investigated by using simple linear regression analysis. To identify the set of presurgical MR imaging features that best predict surgical outcomes, we performed multiple linear regression analysis by using a bidirectional stepwise method. RESULTS: Simple linear regression analyses demonstrated that presurgical high-convexity tightness, callosal angle, and Sylvian fissure dilation were significantly associated with the 1-year changes in the clinical symptoms. A multiple linear regression analysis demonstrated that presurgical high-convexity tightness alone predicted the improvement of the clinical symptoms 1 year after surgery. CONCLUSIONS: High-convexity tightness is a neuroimaging feature predictive of shunt response in idiopathic normal pressure hydrocephalus.

Although confabulations and delusions are observed in Alzheimer’s disease, the relationship between the 2 has not been fully investigated. This study involved 50 patients with Alzheimer’s disease and 10 healthy participants. After the patients were divided into delusional and nondelusional groups, confabulations and cognitive function were assessed. No confabulations appeared in the healthy participants, and only patients with Alzheimer’s disease showed confabulations. The delusional group produced more confabulations on episodic subjects than on semantic subjects. There was a correlation between cognitive impairment and confabulations in semantic memory. These findings suggest that different mechanisms are involved in confabulations between semantic and episodic memories.