Assessment of Cerebrovascular Reactivity with the TCD Through the Submandibular Window

Assessment of Cerebrovascular Reactivity with the TCD Through the Submandibular Window | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Method Article Assessment of Cerebrovascular Reactivity with the TCD Through the Submandibular Window BURAK OZALTUN, Mine Hayriye Sorgun, Canan Togay Isıkay This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7520097/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Purpose Cerebrovascular reactivity (CVR) is commonly assessed via transcranial Doppler ultrasonography (TCD) through the temporal bone window. However, inadequate temporal acoustic windows in some individuals necessitate alternative approaches. This study aimed to evaluate the feasibility of using the submandibular window, to measure breath holding index (BHI) and hyperventilation index (HVI) from the distal internal carotid artery (ICA) and compare these with middle cerebral artery (MCA) measurements obtained via the traditional temporal window. Methods Fifty healthy volunteers (25 females, 25 males; age range: 25–64 years) underwent CVR evaluation using TCD. BHI and HVI were calculated both from the MCA via the temporal window and from the distal ICA via the submandibular window. Each test was repeated twice and averaged. Statistical analyses included descriptive methods and Spearman correlation to assess relationships between variables. Results The mean BHI was significantly higher in the MCA (0.70 ± 0.38) than the ICA (0.55 ± 0.36) (p = 0.017), while HVI values were comparable between arteries (MCA: 0.56 ± 0.15; ICA: 0.51 ± 0.15; p = 0.248). A weak-to-moderate, yet significant, positive correlation was found between MCA and ICA values for both BHI (rs = 0.366, p = 0.009) and HVI (rs = 0.314, p = 0.026). No significant correlation was found between BHI and HVI within either artery. Conclusion While a weak-to-moderate association exists between MCA and ICA measurements, BHI derived from the distal ICA via the submandibular window appears to be less clinically reliable than BHI obtained from the MCA. Submandibular ICA measurements may serve as supportive or alternative tools, especially in cases where the temporal window is insufficient, but should not replace conventional approaches. Trial Registration : Not applicable (cross-sectional observational study). Cerebrovascular Reactivity Transcranial Doppler Submandibular Window Breath Holding Index Hyperventilation Index Internal Carotid Artery Middle Cerebral Artery Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 28 Oct, 2025 Reviews received at journal 23 Oct, 2025 Reviews received at journal 20 Oct, 2025 Reviewers agreed at journal 16 Oct, 2025 Reviewers agreed at journal 16 Oct, 2025 Reviewers agreed at journal 15 Oct, 2025 Reviewers invited by journal 30 Sep, 2025 Editor invited by journal 29 Sep, 2025 Editor assigned by journal 04 Sep, 2025 Submission checks completed at journal 04 Sep, 2025 First submitted to journal 02 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7520097","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Method Article","associatedPublications":[],"authors":[{"id":527867910,"identity":"fb76f35d-14c0-4855-95e3-fe2c10329ba6","order_by":0,"name":"BURAK 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Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Cerebrovascular Reactivity, Transcranial Doppler, Submandibular Window, Breath Holding Index, Hyperventilation Index, Internal Carotid Artery, Middle Cerebral Artery","lastPublishedDoi":"10.21203/rs.3.rs-7520097/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7520097/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose\u0026nbsp; \u003c/strong\u003eCerebrovascular reactivity (CVR) is commonly assessed via transcranial Doppler ultrasonography (TCD) through the temporal bone window. However, inadequate temporal acoustic windows in some individuals necessitate alternative approaches. This study aimed to evaluate the feasibility of using the submandibular window, to measure breath holding index (BHI) and hyperventilation index (HVI) from the distal internal carotid artery (ICA) and compare these with middle cerebral artery (MCA) measurements obtained via the traditional temporal window.\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u0026nbsp; \u003c/strong\u003eFifty healthy volunteers (25 females, 25 males; age range: 25–64 years) underwent CVR evaluation using TCD. BHI and HVI were calculated both from the MCA via the temporal window and from the distal ICA via the submandibular window. Each test was repeated twice and averaged. Statistical analyses included descriptive methods and Spearman correlation to assess relationships between variables.\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u0026nbsp; \u003c/strong\u003eThe mean BHI was significantly higher in the MCA (0.70 ± 0.38) than the ICA (0.55 ± 0.36) (p = 0.017), while HVI values were comparable between arteries (MCA: 0.56 ± 0.15; ICA: 0.51 ± 0.15; p = 0.248). A weak-to-moderate, yet significant, positive correlation was found between MCA and ICA values for both BHI (rs = 0.366, p = 0.009) and HVI (rs = 0.314, p = 0.026). No significant correlation was found between BHI and HVI within either artery.\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u0026nbsp; \u003c/strong\u003eWhile a weak-to-moderate association exists between MCA and ICA measurements, BHI derived from the distal ICA via the submandibular window appears to be less clinically reliable than BHI obtained from the MCA. Submandibular ICA measurements may serve as supportive or alternative tools, especially in cases where the temporal window is insufficient, but should not replace conventional approaches.\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial Registration\u003c/strong\u003e: Not applicable (cross-sectional observational study).\u0026nbsp;\u003c/p\u003e","manuscriptTitle":"Assessment of Cerebrovascular Reactivity with the TCD Through the Submandibular Window","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-14 03:00:22","doi":"10.21203/rs.3.rs-7520097/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-28T11:34:49+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-23T15:50:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-20T13:50:09+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"261718750544365490758426262762355405619","date":"2025-10-16T22:53:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"214531716143060884411986088206563834354","date":"2025-10-16T09:07:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"174259396396872403127640404449259357222","date":"2025-10-15T15:25:45+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-09-30T21:00:54+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-09-29T14:55:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-09-05T02:35:48+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-09-05T02:34:31+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Medicine","date":"2025-09-02T17:20:17+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Medicine](https://link.springer.com/journal/44337)","snPcode":"44337","submissionUrl":"https://submission.springernature.com/new-submission/44337/3","title":"Discover Medicine","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"403d70d9-53dc-4ee2-8da6-45ca904e9bdf","owner":[],"postedDate":"October 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-17T07:40:09+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-14 03:00:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7520097","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7520097","identity":"rs-7520097","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}