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Receiver operating characteristics (ROC) and multivariable analysis were used to assess the screening performance of each measure in differentiating and predicting NPH from non-NPH groups respectively. Temporal changes in the measures on 1-year follow-up MRI in 11 NPH patients (with or without ventriculoperitoneal shunting) were also assessed.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Inter-rater and intra-rater reliability were excellent for all measurements (intraclass correlation coefficients &gt; 0.9). Pairwise comparison showed that SA was statistically different between NPH and AD\/PD\/HC subjects (<jats:italic>p<\/jats:italic> &lt; 0.0001). SA performed the best in predicting NPH, with an area under the ROC curve of &gt; 0.98, and was the only measure left in the final model of the multivariable analysis. Significant (<jats:italic>p &lt; <\/jats:italic>0.01) change in SA was seen at follow-up MRI of NPH patients who were shunted compared to those who were not.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>The SA is readily measured on axial DTI color FA maps compared to the callosal angle and shows superior performance differentiating NPH from neurodegenerative disorders and sensitivity to ventricular changes in NPH after surgical intervention.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Key Points<\/jats:title>\n                <jats:p><jats:italic>\u2022 The splenial angle is a novel simple angular radiological index proposed for idiopathic normal pressure hydrocephalus, measured in the ubiquitous axial plane on DTI color fractional anisotropy maps.<\/jats:italic><\/jats:p>\n                <jats:p><jats:italic>\u2022 The splenial angle quantitates the compression and stretching of the posterior callosal commissural fibers alongside the distended lateral ventricles in idiopathic normal pressure hydrocephalus (NPH) using tools readily accessible in clinical practice and shows excellent test-retest reliability.<\/jats:italic><\/jats:p>\n                <jats:p><jats:italic>\u2022 Splenial angle outperforms Evans\u2019 index and callosal angle in predicting NPH from healthy, Parkinson\u2019s disease, and Alzheimer\u2019s disease subjects on ROC analysis with an area under the curve of &gt; 0.98 and is sensitive to morphological ventricular changes in NPH patients after ventricular shunting.<\/jats:italic><\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00330-021-07871-4","type":"journal-article","created":{"date-parts":[[2021,5,15]],"date-time":"2021-05-15T12:02:25Z","timestamp":1621080145000},"page":"9086-9097","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["The splenial angle: a novel radiological index for idiopathic normal pressure hydrocephalus"],"prefix":"10.1007","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7603-7334","authenticated-orcid":false,"given":"Ling Ling","family":"Chan","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huihua","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda J. 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These were referenced in the manuscript and below:","order":7,"name":"Ethics","group":{"name":"EthicsHeading","label":"Study subjects or cohorts overlap"}},{"value":"\u2022 retrospective\u2022 case-control study \/ cross-sectional study \/ prognostic study \/ observational\u2022 performed at one institution","order":8,"name":"Ethics","group":{"name":"EthicsHeading","label":"Methodology"}}]}}