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Non-SIH patients (<jats:italic>n<\/jats:italic>\u202f=\u200920) undergoing CT myelography served as controls. The renal pelvis density on postmyelography CT was measured in all patients. Mean difference in renal pelvis density between the groups was calculated.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>In total, 111 SIH patients (mean age 48\u202f\u00b1\u200913\u00a0years; 60% female) were included, 71\u00a0(64%) SLEC(+) and 40 (36%) SLEC(\u2212). The adjusted renal pelvis density in the SLEC(+), SLEC(\u2212), and the non-SIH group was 108\u202fHounsfield unit (HU), 83\u202fHU, and 32\u202fHU, respectively, resulting in a\u00a0significant difference between SLEC(+) vs. control group\u00a01 (75\u202fHU, <jats:italic>p<\/jats:italic>\u202f&lt;\u20090.001), SLEC(\u2212) vs. control group\u00a01 (50\u202fHU, <jats:italic>p<\/jats:italic>\u202f&lt;\u20090.001), and a\u00a0tendency for higher density in SLEC(+) than SLEC(\u2212) (25\u202fHU, <jats:italic>p<\/jats:italic>\u202f=\u20090.16).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>Increased renal pelvis opacification on postmyelography CT was observed in SIH patients, even in the absence of a\u00a0CSF leak or a\u00a0CSF venous fistula, when compared to non-SIH patients. Although the provenance of early renal opacification in SLEC (\u2212) SIH patients remains unclear, our results suggest that it may be a\u00a0surrogate for increased spinal CSF resorption via spinal arachnoid granulations and along spinal nerve sheaths occult to direct imaging.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00062-021-01042-0","type":"journal-article","created":{"date-parts":[[2021,6,25]],"date-time":"2021-06-25T07:02:37Z","timestamp":1624604557000},"page":"529-536","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Renal Pelvis Opacification on Postmyelography Computed Tomography as an Indicator for Cerebrospinal Fluid Loss in Spontaneous Intracranial Hypotension"],"prefix":"10.1007","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5609-0998","authenticated-orcid":false,"given":"Eike I.","family":"Piechowiak","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"B\u00e4r","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Levin","family":"H\u00e4ni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mattia","family":"Branca","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johannes","family":"Kaesmacher","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pasquale","family":"Mordasini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Raabe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian T.","family":"Ulrich","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Gralla","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00fcrgen","family":"Beck","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomas","family":"Dobrocky","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2021,6,25]]},"reference":[{"key":"1042_CR1","doi-asserted-by":"publisher","first-page":"2286","DOI":"10.1001\/jama.295.19.2286","volume":"295","author":"WI Schievink","year":"2006","unstructured":"Schievink\u00a0WI. 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