{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T20:35:35Z","timestamp":1781901335799,"version":"3.54.5"},"reference-count":12,"publisher":"Scientific Scholar","content-domain":{"domain":["surgicalneurologyint.com"],"crossmark-restriction":true},"short-container-title":[],"abstract":"\nBackground: <\/jats:title>\nSpinal arachnoid webs (SAW) occur when abnormally thickened bands of arachnoid membranes commonly located dorsal to the thoracic spine cause blockage of normal cerebrospinal fluid (CSF) flow, resulting in focal cord compression and myelopathy. The pathognomonic MR finding for SAW is the \u201cpositive scalpel sign\u201d comprised of an enlarged dorsal CSF space with a normal ventral subarachnoid space. The main differential diagnostic consideration for SAW is idiopathic spinal cord herniation (ISCH); however, for ISCH, MR studies classically demonstrate ventral displacement of the spinal cord through an anterior dural defect. Here, we describe a 60-year-old female with an atypical SAW at the T3-T4 level (i.e., the preoperative MR failed to demonstrate the \u201cpositive scalpel sign\u201d). Nevertheless, at surgery, intraoperative ultrasonography confirmed that SAW was present and was decompressed\/marsupialized\/removed.<\/jats:p>\n<\/jats:sec>\n\nCase Description: <\/jats:title>\nA 60-year-old female presented with sensory impairment to both lower extremities. The thoracic MR images showed an enlarged dorsal CSF space at the T3-T4 level but without the \u201cscalpel sign\u201d suggesting \u201cinterruption\u201d of CSF flow by thickened bands of focal dorsal arachnoidal tissues. Although the initial preoperative diagnosis was ISCH, intraoperative ultrasound (IOUS) confirmed the presence of a thickened arachnoid band, confirming the diagnosis of a SAW that was appropriately decompressed\/resected.<\/jats:p>\n<\/jats:sec>\n\nConclusion: <\/jats:title>\nCorrectly, establishing the preoperative diagnosis of a SAW based on MR imaging may sometimes be difficult as the typical \u201cscalpel sign\u201d may not be present in all patients. Notably, in cases like this one, IOUS may critically confirm the diagnosis of SAW thus leading to appropriate SAW decompression\/removal.<\/jats:p>\n<\/jats:sec>","DOI":"10.25259\/sni_179_2022","type":"journal-article","created":{"date-parts":[[2022,3,25]],"date-time":"2022-03-25T11:19:41Z","timestamp":1648207181000},"page":"108","update-policy":"https:\/\/doi.org\/10.25259\/crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Atypical radiographic case of arachnoid web without scalpel sign"],"prefix":"10.25259","volume":"13","author":[{"given":"Yoshitaka","family":"Nagashima","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yusuke","family":"Nishimura","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroshi","family":"Ito","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takahiro","family":"Oyama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomoya","family":"Nishii","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomomi","family":"Gonda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroyuki","family":"Kato","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryuta","family":"Saito","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10894","published-online":{"date-parts":[[2022,3,25]]},"reference":[{"key":"10.25259\/SNI_179_2022\/ref-1","doi-asserted-by":"crossref","first-page":"446","DOI":"10.21037\/jss.2018.05.08","article-title":"Spinal arachnoid web-a review article","volume":"4","author":"Ben Ali","year":"2018","journal-title":"J Spine Surg"},{"key":"10.25259\/SNI_179_2022\/ref-2","doi-asserted-by":"crossref","first-page":"707","DOI":"10.1007\/s00701-003-0071-9","article-title":"Syringomyelia and the arachnoid web","volume":"145","author":"Brodbelt","year":"2003","journal-title":"Acta Neurochirurg (Wien)"},{"key":"10.25259\/SNI_179_2022\/ref-3","doi-asserted-by":"crossref","first-page":"227","DOI":"10.3171\/2013.10.SPINE13395","article-title":"Dorsal spinal arachnoid web diagnosed with the quantitative measurement of cerebrospinal fluid flow on magnetic resonance imaging","volume":"20","author":"Chang","year":"2014","journal-title":"J Neurosurg Spine"},{"key":"10.25259\/SNI_179_2022\/ref-4","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1097\/BSD.0000000000000569","article-title":"Microscope and fiberscope-assisted subarachnoid-subarachnoid (S-S) bypass: A novel surgical technique to reestablish cerebrospinal fluid flow in treating dorsal spinal arachnoid webs, diagnosed by cine-MRI","volume":"31","author":"Fujiwara","year":"2018","journal-title":"Clin Spine Surg"},{"key":"10.25259\/SNI_179_2022\/ref-5","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1007\/s10143-006-0029-5","article-title":"Unraveling the riddle of syringomyelia","volume":"29","author":"Greitz","year":"2006","journal-title":"Neurosurg Rev"},{"key":"10.25259\/SNI_179_2022\/ref-6","doi-asserted-by":"crossref","first-page":"1007","DOI":"10.1007\/s10143-019-01123-2","article-title":"Image guidance in spine tumor surgery","volume":"43","author":"Kelly","year":"2020","journal-title":"Neurosurg Rev"},{"key":"10.25259\/SNI_179_2022\/ref-7","doi-asserted-by":"crossref","first-page":"568","DOI":"10.3171\/2014.6.SPINE13682","article-title":"Thoracic discectomy by posterior pedicle-sparing, transfacet approach with real-time intraoperative ultrasonography: Clinical article","volume":"21","author":"Nishimura","year":"2014","journal-title":"J Neurosurg Spine"},{"key":"10.25259\/SNI_179_2022\/ref-8","doi-asserted-by":"crossref","first-page":"175","DOI":"10.3171\/2019.1.SPINE181371","article-title":"Arachnoid web of the spine: A systematic literature review","volume":"31","author":"Nisson","year":"2019","journal-title":"J Neurosurg Spine"},{"key":"10.25259\/SNI_179_2022\/ref-9","first-page":"287","article-title":"Dorsal arachnoid web with spinal cord compression: Variant of an arachnoid cyst? Report of two cases","volume":"93","author":"Paramore","year":"2000","journal-title":"J Neurosurg"},{"key":"10.25259\/SNI_179_2022\/ref-10","doi-asserted-by":"crossref","first-page":"1104","DOI":"10.3174\/ajnr.A3432","article-title":"Dorsal thoracic arachnoid web and the \u201cscalpel sign\u201d: A distinct clinical-radiologic entity","volume":"34","author":"Reardon","year":"2013","journal-title":"AJNR Am J Neuroradiol"},{"key":"10.25259\/SNI_179_2022\/ref-11","doi-asserted-by":"crossref","first-page":"754","DOI":"10.3171\/2016.11.SPINE16696","article-title":"Differentiation of idiopathic spinal cord herniation from dorsal arachnoid webs on MRI and CT myelography","volume":"26","author":"Schultz","year":"2017","journal-title":"J Neurosurg Spine"},{"key":"10.25259\/SNI_179_2022\/ref-12","doi-asserted-by":"crossref","first-page":"97","DOI":"10.4103\/1793-5482.116386","article-title":"Idiopathic spinal cord herniation: Clinical review and report of three cases","volume":"8","author":"Summers","year":"2013","journal-title":"Asian J Neurosurg"}],"container-title":["Surgical Neurology International"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/surgicalneurologyint.com\/atypical-radiographic-case-of-arachnoid-web-without-scalpel-sign\/","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"http:\/\/surgicalneurologyint.com\/surgicalint-articles\/atypical-radiographic-case-of-arachnoid-web-without-scalpel-sign\/","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,3,25]],"date-time":"2022-03-25T11:19:50Z","timestamp":1648207190000},"score":1,"resource":{"primary":{"URL":"http:\/\/surgicalneurologyint.com\/surgicalint-articles\/atypical-radiographic-case-of-arachnoid-web-without-scalpel-sign\/"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,3,25]]},"references-count":12,"alternative-id":["10.25259\/SNI_179_2022"],"URL":"https:\/\/doi.org\/10.25259\/sni_179_2022","relation":{},"ISSN":["2152-7806"],"issn-type":[{"value":"2152-7806","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,3,25]]},"article-number":"108"}}