Effect of CT Attenuation–Stratified Stone Volume on Treatment Outcomes of Shock Wave Lithotripsy for Ureteral Stones

Effect of CT Attenuation–Stratified Stone Volume on Treatment Outcomes of Shock Wave Lithotripsy for Ureteral Stones | 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 Research Article Effect of CT Attenuation–Stratified Stone Volume on Treatment Outcomes of Shock Wave Lithotripsy for Ureteral Stones Kota Iida, Yuriko Hayashi, Kosuke Mieda, Yoshitaka Itami, Yukinari Hosokawa This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9142951/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Objectives: Recent advances in three-dimensional (3D) imaging enable precise evaluation of stone characteristics. We investigated predictors of shock wave lithotripsy (SWL) outcomes using CT attenuation–stratified stone volume. Methods: We retrospectively analyzed 313 patients who underwent SWL for ureteral stones between August 2020 and January 2025. Stone-related parameters were measured using 3D imaging software (SYNAPSE VINCENT®), stratifying each stone into seven CT attenuation categories (<1000 HU; 1000–1500 HU in 100-HU increments; ≥1500 HU). A derivation cohort of 259 patients treated with Piezolith® (August 2020–July 2023) determined optimal cutoff values, which were validated in 54 patients treated with Compact Sigma® (August 2023–January 2025). The primary endpoint was conversion to ureteroscopy (URS). Results : Overall, 274 patients (87.5%) achieved SWL success, while 39 (12.5%) required URS. In the validation cohort, predictors of conversion included maximum stone length ≥8.7 mm (OR 7.8, P = 0.02), maximum CT value ≥1487 HU (OR 5.3, P = 0.07), mean CT value ≥535 HU (OR 13.2, P = 0.008), total stone volume ≥152 mm³ (OR 13.2, P = 0.008), and volumes of stone components with CT attenuation ≥1000-1500 HU. Among these, the volume of components ≥1200 HU (21.5 mm³) demonstrated the highest predictive performance (OR 17.7, P = 0.002). Conclusions: CT attenuation–stratified stone volume, particularly components ≥1200 HU, is a strong predictor of SWL failure requiring conversion to URS. Incorporating attenuation-based volumetric analysis into pre-treatment evaluation may improve patient selection and optimize treatment strategy for ureteral stones. Shock wave lithotripsy CT attenuation–stratified volume Ureteral stone Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 23 Mar, 2026 Editor assigned by journal 17 Mar, 2026 Submission checks completed at journal 17 Mar, 2026 First submitted to journal 16 Mar, 2026 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-9142951","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":610534638,"identity":"873898e3-a2cc-4df9-97ee-eb4ab33fb691","order_by":0,"name":"Kota Iida","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABA0lEQVRIiWNgGAWjYBACCRCRYCAhx8aQwPiAgeEAVJwHnxZmBoYHFTbGQC3MBkRrYXxwJi0RaBebBEILHiDZ3n/wQ2Lb4QQ+9uRn1Tw1d+T4GZgfPmCQuYNTizTPYWYJoJY8Np5nZrd5jj0zlmxgMzZg4HmGU4ucRDIDSEsxm0QCUAvb4cQNB3iALuQ5jE8L8w+glsQ2ifRvxTz/iNAiLZEMNB/o/TaJHDNm3jYitEj2HDazSAAFMs+bYsm5fYeNJZuBfknA4xeJ442Pb/4ARqV8e/rGD2++HZbjZ29++OBjD+4QQwFM4AgExi1DYs8B4rQw/oAzfxCpZRSMglEwCkYCAABh1VTxwzuDzAAAAABJRU5ErkJggg==","orcid":"","institution":"Tane General Hospital","correspondingAuthor":true,"prefix":"","firstName":"Kota","middleName":"","lastName":"Iida","suffix":""},{"id":610534640,"identity":"92b604ef-79de-4549-b8e6-67b25b2603d2","order_by":1,"name":"Yuriko Hayashi","email":"","orcid":"","institution":"Tane General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yuriko","middleName":"","lastName":"Hayashi","suffix":""},{"id":610534642,"identity":"cf179061-3e4c-44f6-9da0-dc3c417c2727","order_by":2,"name":"Kosuke Mieda","email":"","orcid":"","institution":"Tane General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Kosuke","middleName":"","lastName":"Mieda","suffix":""},{"id":610534646,"identity":"e987e632-2a61-4f20-8482-35829c4b5471","order_by":3,"name":"Yoshitaka Itami","email":"","orcid":"","institution":"Tane General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yoshitaka","middleName":"","lastName":"Itami","suffix":""},{"id":610534648,"identity":"d6461c88-bb00-4316-b5d5-dbee5068a257","order_by":4,"name":"Yukinari Hosokawa","email":"","orcid":"","institution":"Tane General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yukinari","middleName":"","lastName":"Hosokawa","suffix":""}],"badges":[],"createdAt":"2026-03-17 02:23:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9142951/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9142951/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105567210,"identity":"d72c65f2-8049-439e-89f5-fb27c94eca45","added_by":"auto","created_at":"2026-03-27 12:58:42","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":500189,"visible":true,"origin":"","legend":"","description":"","filename":"manuscripts.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9142951/v1_covered_292adbd1-aff1-464e-8406-9d4c457bbd7a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect of CT Attenuation–Stratified Stone Volume on Treatment Outcomes of Shock Wave Lithotripsy for Ureteral Stones","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"urolithiasis","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ures","sideBox":"Learn more about [Urolithiasis](http://link.springer.com/journal/240)","snPcode":"240","submissionUrl":"https://submission.nature.com/new-submission/240/3","title":"Urolithiasis","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Shock wave lithotripsy, CT attenuation–stratified volume, Ureteral stone","lastPublishedDoi":"10.21203/rs.3.rs-9142951/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9142951/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjectives: \u003c/strong\u003eRecent advances in three-dimensional (3D) imaging enable precise evaluation of stone characteristics. We investigated predictors of shock wave lithotripsy (SWL) outcomes using CT attenuation–stratified stone volume.\u003cbr\u003e\n \u003cstrong\u003eMethods: \u003c/strong\u003eWe retrospectively analyzed 313 patients who underwent SWL for ureteral stones between August 2020 and January 2025. Stone-related parameters were measured using 3D imaging software (SYNAPSE VINCENT®), stratifying each stone into seven CT attenuation categories (\u0026lt;1000 HU; 1000–1500 HU in 100-HU increments; ≥1500 HU). A derivation cohort of 259 patients treated with Piezolith® (August 2020–July 2023) determined optimal cutoff values, which were validated in 54 patients treated with Compact Sigma® (August 2023–January 2025). The primary endpoint was conversion to ureteroscopy (URS).\u003cbr\u003e\n \u003cstrong\u003eResults\u003c/strong\u003e: Overall, 274 patients (87.5%) achieved SWL success, while 39 (12.5%) required URS. In the validation cohort, predictors of conversion included maximum stone length ≥8.7 mm (OR 7.8, P = 0.02), maximum CT value ≥1487 HU (OR 5.3, P = 0.07), mean CT value ≥535 HU (OR 13.2, P = 0.008), total stone volume ≥152 mm³ (OR 13.2, P = 0.008), and volumes of stone components with CT attenuation ≥1000-1500 HU. Among these, the volume of components ≥1200 HU (21.5 mm³) demonstrated the highest predictive performance (OR 17.7, P = 0.002).\u003cbr\u003e\n \u003cstrong\u003eConclusions:\u003c/strong\u003e CT attenuation–stratified stone volume, particularly components ≥1200 HU, is a strong predictor of SWL failure requiring conversion to URS. Incorporating attenuation-based volumetric analysis into pre-treatment evaluation may improve patient selection and optimize treatment strategy for ureteral stones.\u003c/p\u003e","manuscriptTitle":"Effect of CT Attenuation–Stratified Stone Volume on Treatment Outcomes of Shock Wave Lithotripsy for Ureteral Stones","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-26 15:46:35","doi":"10.21203/rs.3.rs-9142951/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-23T09:05:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-17T09:05:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-17T09:05:43+00:00","index":"","fulltext":""},{"type":"submitted","content":"Urolithiasis","date":"2026-03-17T02:07:21+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"urolithiasis","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ures","sideBox":"Learn more about [Urolithiasis](http://link.springer.com/journal/240)","snPcode":"240","submissionUrl":"https://submission.nature.com/new-submission/240/3","title":"Urolithiasis","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"e90b8851-f52b-4548-9889-3a88079f1dfd","owner":[],"postedDate":"March 26th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-26T15:46:35+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-26 15:46:35","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9142951","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9142951","identity":"rs-9142951","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}