Enhancing Precision in Vascular Embolization: Evaluating the Effectiveness of the Intentional Early Detachment Technique with Detachable Coils in Complex Cases

Enhancing Precision in Vascular Embolization: Evaluating the Effectiveness of the Intentional Early Detachment Technique with Detachable Coils in Complex Cases | 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 Enhancing Precision in Vascular Embolization: Evaluating the Effectiveness of the Intentional Early Detachment Technique with Detachable Coils in Complex Cases Shojiro Oka, Shigeshi Kohno, Shigeki Arizono, Yasuyuki Onishi, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3987357/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 25 Apr, 2024 Read the published version in CVIR Endovascular → Version 1 posted 4 You are reading this latest preprint version Abstract Background This study aimed to assess the effectiveness and versatility of an intentional early detachment technique with detachable coils to address challenging vascular embolization scenarios. This novel approach aims to provide interventional radiologists with an alternative method for achieving precise coil placement when standard methods of detachable coil placement are rendered ineffective owing to vascular anatomy or limited available equipment. Materials and Methods This was a retrospective study comprising 11 patients (9 males and 2 females; median age, 77 years) who underwent embolization procedures using the intentional early detachment technique via 1.6-Fr or 1.3-Fr microcatheters between October 2021 and December 2023. In this technique, detachable coils were intentionally detached within the microcatheter and placed using saline flushing. Technical success, complications, and clinical success were evaluated. Results The technique was applied in three distinct scenarios: tortuous vascular anatomy (4 cases), inadequate system backup (3 cases), and 1.3-Fr microcatheter use (4 cases). The technical and clinical success rates were 100%. No complications were observed, and there were no cases of coil migration or malpositioning. Conclusion The intentional early detachment technique is valuable for interventional radiologists and offers a solution for challenging vascular embolization scenarios. Although its application is limited to specific circumstances, it can significantly enhance coil placement in complex cases, thereby contributing to improved patient care. Detachable coils Vascular embolization Tortuous pathways Coil detachment Saline flushing Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Since their development in 1991, detachable coils have been recognized for their effectiveness and safety in the field of vascular embolization, especially in neurointervention [ 1 – 4 ]. Attached to a delivery wire, these coils can be deployed with control and precision. They have become an important part of the interventional toolkit in cases where precision is essential and downstream nontarget embolization would be catastrophic [ 5 ]. However, some situations present unique challenges. In particular, the successful deployment of detachable coils can become challenging when dealing with tortuous vessels or when the backup support of the microcatheter is insufficient. Recent advancements in catheter systems have facilitated the catheterization of tortuous or narrow branches through the use of exceptionally thin microcatheters [ 6 , 7 ]. However, the narrow inner lumen of these thin catheters limits the types of coils that can be deployed. Especially with 1.3-Fr microcatheters, the use of coils is almost incompatible. To address these challenges, we herein describe an intentional early detachment technique with detachable coils. This novel technique offers a solution for vascular embolization of tortuous or narrow branches that are only accessible with thin microcatheters. By intentionally detaching the detachable coils within the microcatheters and flushing them with saline, interventional radiologists can achieve precise coil placement. We explore the application of the intentional early detachment technique in 11 patients, each presenting unique challenges. Our investigation aims to shed light on the effectiveness and versatility of this technique, providing interventional radiologists with a viable alternative for complex scenarios and ultimately enhancing patient care. Materials and methods Patients All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Our local Institutional Review Board approved the study (approval number: Zn240208) and waived the need for written informed consent. Between October 2021 and December 2023, 11 embolizations were performed on 11 patients (9 males and 2 females, with a median age of 77 [range, 52–87] years) using the intentional early detachment technique with detachable coils through a 1.6-Fr or 1.3-Fr microcatheter. Procedure In all cases, this technique was used when it was not possible to embolize the vessel by standard methods of detachable coil placement, and the operator considered embolization with a liquid embolic material inappropriate. We advanced the coil through the microcatheter until the delivery wire could enter without resistance or the microcatheter’s kickback, then intentionally detached the coil within the microcatheter, followed by flushing the coil with saline (Fig. 1 ). Of note, some electrically detachable coils such as the iED coil (KANEKA Medics, Osaka, Japan) and the Target coil (Stryker, Fremont, CA, USA) may not be detachable within the catheter. When using this type of coils, advancing only the coil portion into the microcatheter and ensuring that the detachment point was slightly within the catheter hub allowed for successful detachment (Fig. 2 ). Evaluation The primary outcome parameter was technical success, defined as when the coils were delivered and placed successfully at the target vessel without migration. Complications and clinical success rates were also evaluated. Clinical success was defined as complete cessation of blood flow at the target vessel by post-embolization angiogram. Complications were evaluated using the Cardiovascular and Interventional Radiological Society of Europe classification system [ 8 ]. All images were interpreted by two radiologists with more than eight years of experience in diagnostic and interventional radiology. Any disagreements or discrepancies were resolved by consensus. Results Details of the patient's diseases and the vessels that underwent embolization are summarized in Table 1 . Table 1 The 11 patients who underwent coil embolization using the intentional early detachment technique with detachable coils. Patient No /Age /Sex Embolized artery Etiology Coil: diameter in mm/ length in cm No of coils Microcatheters Reasons for intentional early detachment Technical/Clinical success Complication 1/75/M PIPDA Hemorrhage within a pancreatic tumor Target XL soft: 6/20 1 Carnelian MARVEL S, Swift Ninja Significant tortuosity in vascular anatomy YES/YES NO 2/75/F DPA True aneurysm due to MALS Target nano: 1/2, 1/3(×3) 4 Carnelian MARVEL S, Swift Ninja Inadequate system backup YES/YES NO 3/79/F PIPDA Post-EST hemorrhage SMART Coil: 1/2 1 Carnelian MARVEL S 1.3, Masters HF Deployment of coils through a 1.3-Fr catheter YES/YES NO 4/83/M Iliolumbar artery Lt-IIAA Embolization to prevent T2EL Avenir: 3/10, 2/8, 2/6 3 Carnelian MARVEL S, Swift Ninja Inadequate system backup YES/YES NO 5/86/M VR Diverticular hemorrhage Avenir: 1.5/3(×2),2/4, 2/3(×2) iED coil: 1/3 6 Carnelian MARVEL S, Masters HF Inadequate system backup YES/YES NO 6/86/M 4th LA T2EL Avenir: 4/20 1 Carnelian MARVEL S, Swift Ninja Significant tortuosity in vascular anatomy YES/YES NO 7/76/M 2nd LA T2EL Avenir: 4/20, 3/10, 4/13(×2), 5/17(×2) Target tetra: 3.5/8(×2) 8 Carnelian MARVEL S 1.3, Masters HF Deployment of coils through a 1.3-Fr catheter YES/YES NO 8/87/M 4th LA T2EL AZUR soft3D: 3/8 Avenir: 4/20 2 Carnelian MARVEL S, Swift Ninja Significant tortuosity in vascular anatomy YES/YES NO 9/52/M AIPDA Hemorrhage due to SAM Avenir PICO: 1/2(×2) 2 Carnelian MARVEL S 1.3, Swift Ninja Deployment of coils through a 1.3-Fr catheter YES/YES NO 10/74/M Cystic artery Idiopathic gallbladder bleeding Target nano: 1/2(×2) 2 Guidepost, DeFrictor Nano, Carnelian MARVEL S Deployment of coils through a 1.3-Fr catheter YES/YES NO 11/69/M 3rd ICA Preemptive embolization to prevent T2EL Target XL: 5/10(×2), 4/15(×5) Azur soft3D: 4/10 8 Carnelian MARVEL S, Swift Ninja Significant tortuosity in vascular anatomy YES/YES NO AIPDA: anterior inferior pancreaticoduodenal artery, PIPDA: posterior inferior pancreaticoduodenal artery, DPA: dorsal pancreatic artery, LA: lumber artery, MALS: median arcuate ligament syndrome, EST: endoscopic sphincterotomy, ICA: intercostal artery, IIAA: internal iliac artery aneurysm, VR: vasa recta, T2EL: type 2 endoleak, SAM: segmental arterial mediolysis, Target XL soft/Nano/Tetra (Stryker, Fremont, CA, USA), SMART COIL (Penumbra, Alameda, CA, USA), AVENIR/AVENIR PICO (Wallaby Medical, Shanghai, China), AZUR soft 3D (Terumo, Tokyo, Japan), iED coil (KANEKA Medix, Osaka, Japan) Carnelian MARVEL S/S 1.3 (Tokai Medical Products, Aichi, Japan), Swift NINJA (SB KAWASUMI, Tokyo, Japan), Masters HF (Asahi Intecc, Aichi, Japan), DeFrictor Nano (Medico's Hirata, Osaka, Japan), Guidepost (Tokai Medical Products) The intentional early detachment technique was primarily employed in three distinct clinical scenarios in our study (Fig. 3 ). The first scenario involved cases in which the vascular anatomy exhibited significant tortuosity, making it challenging to push the delivery wire of a detachable coil through microcatheters (n = 4/11). Figure 4 demonstrates a representative case. The second scenario involved situations in which inadequate system backup resulted in microcatheter kickbacks during coil placement. In turn, microcatheter kickback poses challenges in tightly placing detachable coils, and there was also a potential risk of catheter dislodgment into the mother vessel (n = 3/11). Figure 5 demonstrates a representative case. The third scenario included cases in which coils were deployed through a 1.3-Fr microcatheter (n = 4/11). Figure 6 demonstrates a representative case. Technical and clinical success rates were both 100% in all scenarios. In all cases, the triaxial system, advancing a small microcatheter from a large microcatheter, was introduced initially as the target arteries appeared to be small and/or tortuous on preprocedural computed tomography images. No coil sticking in the microcatheter, malposition in the target vessel, or migration into non-target vessels occurred. No major complications occurred. Discussion When faced with tortuous and meandering vascular pathways, the stiffness of the delivery wires can sometimes impede the complete deployment of detachable coils within the vessel [ 9 ]. In such a scenario, attempts to use coils from different manufacturers, even those with distinct characteristics, can still pose challenges. Although improving the backup support system is plausible [ 10 ], this method has its limitations when navigating thick-diameter catheters through highly tortuous pathways [ 11 ]. The effectiveness of triaxial systems for navigating through bent pathways has also been reported [ 12 , 13 ]; however, we used triaxial systems in all our cases and could not place the coils through standard methods. Although embolization with pushable coils using a saline flushing technique has been reported to be effective [ 14 , 15 ], it may not be suitable in cases where there is a lack of appropriately sized coils that are feasible for large vessel diameters. In Japan, 0.014-inch pushable coils (C-STOPPER coil; Piolax, Kanagawa, Japan) with a diameter of 2.8 mm are available for use with 1.6-Fr microcatheters. However, in vessels with diameters greater than 2.8 mm, the risk of migration is high, limiting the use of pushable coils. In such situations, intentionally detaching a larger-diameter detachable coil within the microcatheter and subsequently flushing it with saline allows for secure placement without the risk of migration (Fig. 4 c, d). In cases where the backup support is inadequate, even if the entire length of the coil can be delivered from the catheter, the kickback effect of the microcatheter during placement can prevent tight embolization or lead to catheter deviation into the mother vessel. Under such circumstances, the intentional early detachment technique with the detachable coils can reliably achieve a tight placement. In one of our patients (Fig. 5 ), we initially attempted to place an iED coil measuring 1 mm in diameter and 3 cm in length in the vasa recta of the first sigmoid artery. However, due to difficulties in catheter control and kickback, only loose placement was achieved (Fig. 6 c). Subsequently, we retrieved the coil and intentionally detached it, followed by flushing with saline, resulting in tight embolization (Fig. 6 d). In scenarios involving highly tortuous vessel pathways that require the use of ultra-thin microcatheters with a distal tip size of 1.5-Fr or less, these microcatheters are designed for use with liquid embolic materials and are essentially incompatible with coils. Previous reports have mentioned that detachable coils can be used with a 1.5-Fr Marathon microcatheter (Medtronic, Minneapolis, MN, USA) [ 9 , 16 , 17 ]. The inner lumen at the tip is as small as 0.013 inches, limiting the types of coils that can be used. The inner lumen of microcatheters with a distal tip size of 1.3-Fr, such as the DeFrictor Nano (Medico's Hirata, Osaka, Japan) and Marvel S 1.3 (Tokai Medical Products, Aichi, Japan), is even narrower (0.011 inches). In our experience, standards methods are unsuitable for deploying coils through such narrow lumen microcatheters. This limitation is due to the diameter of the coil’s delivery wire being larger than that of the inner lumen of these microcatheters. However, we noticed that, with the so-called 10-coil (0.0095–0.011 inches in primary diameter), only the coil portion of the detachable coil can be inserted into the catheter, as the primary coil diameter of 10-coil is smaller than that of the lumen of 1.3-Fr microcatheters. Therefore, using a 1.3-Fr microcatheter, we advanced the 10-coil through the microcatheter to a point where the delivery wire could enter without resistance, detached the coil, and subsequently flushed it with saline. This method enabled us to achieve embolization with 10-coils, even through a 1.3-Fr microcatheter. Some electrically detachable coils may not be detachable within the catheter as the detachment point must be energized for detachment and requires surrounding electrolytes, including blood or saline solution. Consequently, detachment within the catheter may not always be feasible using coils such as the iED coil and the Target coil. While the Target coils can sometimes be detached within a 1.6-Fr catheter after multiple detachment attempts, they often cannot be detached within a 1.3-Fr catheter. This is due to the narrow lumen leading to an insufficient amount of electrolytes around the detachment point. This study had some limitations. It was a retrospective study conducted at a single facility and included a limited number of patients. Should 0.010-inch pushable coils or 0.014-inch pushable coils with larger diameters become commercially available, they might serve as alternatives to the intentional early detachment technique with detachable coils. In the described technique, detachable coils are employed similarly to how pushable coils would be, meaning that the coil's position cannot be adjusted through repeated retrieval and repositioning during the deployment procedure. Additionally, detachable coils are more expensive than pushable coils. Nonetheless, this study underscores the potential utility of alternative techniques in situations where conventional approaches are limited by vascular anatomy or equipment availability. Conclusion This study demonstrates the effectiveness of the intentional early detachment technique for detachable coils in complex vascular embolization scenarios. This method has been successfully applied to complex cases, enabling coil placement in challenging vascular embolization scenarios. While its applicability is specific to certain scenarios, this technique offers a valuable option for interventionalists when faced with anatomical or equipment constraints. Abbreviations Abbreviations used in this manuscript are limited to figure legends and are not utilized within the main text. Declarations Ethics approval and consent to participate All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The Institutional Review Board (IRB) of Kobe City Medical Center General Hospital approved the study (approval number: Zn240208), and the need for informed consent was waived. Consent for publication For this type of study, formal consent was not required. Availability of data and materials Data sharing is not applicable to this article, as no datasets were generated or analyzed in the current study. Competing interests The authors declare that they have no competing interests. Funding No funding was received for conducting this study. Authors contribution: All authors contributed to the conception and design of this study. SO, SK, and SA performed material preparation, data collection, and analysis. SO wrote the first draft of the manuscript, and all authors commented on the previous versions of the paper. All authors have read and approved the final version of the manuscript. Acknowledgements We would like to thank Editage (www.editage.jp) for English language editing. References Guglielmi G, Viñuela F, Dion J, Duckwiler G (1991) Electrothrombosis of saccular aneurysms via endovascular approach. Part 2: Preliminary clinical experience. J Neurosurg 75:8–14. doi.org/10.3171/jns.1991.75.1.0008 Hui FK, Fiorella D, Masaryk TJ, Rasmussen PA, Dion JE (2014) A history of detachable coils: 1987–2012. J Neurointerventional Surg 6:134–138. 10.1136/neurintsurg-2013-010670 Campos JK, Lien BV, Wang AS, Lin L-M (2020) Advances in endovascular aneurysm management: coiling and adjunctive devices. 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Cardiovasc Intervent Radiol 29(6):986–990. 10.1007/s00270-005-0364-x Stidd DA, Lopes DK, Chen M (2014) Aneurysm coil embolization using a 1.5-fr distal outer diameter microcatheter. Neurointervention 9(1):39–44. 10.5469/neuroint.2014.9.1.39 Wang X, Yu J (2024) Coiling of an iatrogenic aneurysm of the distal posterior inferior cerebellar artery via a Marathon microcatheter. Interdiscip Neurosurg 36:101950. 10.1016/j.inat.2023.101950 Cite Share Download PDF Status: Published Journal Publication published 25 Apr, 2024 Read the published version in CVIR Endovascular → Version 1 posted Reviewers agreed at journal 07 Mar, 2024 Reviewers invited by journal 07 Mar, 2024 Editor assigned by journal 06 Mar, 2024 First submitted to journal 04 Mar, 2024 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-3987357","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":276926112,"identity":"df54985c-df46-44ae-afc8-c470f348ebd1","order_by":0,"name":"Shojiro Oka","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA40lEQVRIiWNgGAWjYDACCQYGgwQGhno2ZuYDIK4M0VoS+NjZEkBcHqK0gECCHD+PAYhBWIv87OYDBQ/32OSxMfN8fnWjxoKHgf3w0Q34tBjcOZZgkPAsrZiNmXebdc4xoMN40tJu4NUikWNgkHDgMGMbUItxDhtQiwSPGV4t8jPgWnieGef8I0ILww2IlkSgFubHuW1EaDG4kQb0y4E0YzZmNjPm3D4JHjZCfpGfkXzM8McBGzn5/sOPP+d8q5PjZz98DL/DGBjYDGAMcByxEVAOAswPYIwPRKgeBaNgFIyCEQgAeohCau5uuBAAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0003-2416-7393","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":true,"prefix":"","firstName":"Shojiro","middleName":"","lastName":"Oka","suffix":""},{"id":276926113,"identity":"c5f81408-6e68-48cd-a6a3-cf137de6720d","order_by":1,"name":"Shigeshi Kohno","email":"","orcid":"","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":false,"prefix":"","firstName":"Shigeshi","middleName":"","lastName":"Kohno","suffix":""},{"id":276926114,"identity":"abacbe65-76c7-45ec-89d4-86c90521203b","order_by":2,"name":"Shigeki Arizono","email":"","orcid":"","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":false,"prefix":"","firstName":"Shigeki","middleName":"","lastName":"Arizono","suffix":""},{"id":276926115,"identity":"566b7934-1b98-4f98-83cc-a6a316dda6fd","order_by":3,"name":"Yasuyuki Onishi","email":"","orcid":"","institution":"Kyoto University Graduate School of Medicine Faculty of Medicine: Kyoto Daigaku Daigakuin Igaku Kenkyuka Igakubu","correspondingAuthor":false,"prefix":"","firstName":"Yasuyuki","middleName":"","lastName":"Onishi","suffix":""},{"id":276926116,"identity":"74182a01-dc07-465b-b4e1-44b6aa4d328d","order_by":4,"name":"Masaya Fumimoto","email":"","orcid":"","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":false,"prefix":"","firstName":"Masaya","middleName":"","lastName":"Fumimoto","suffix":""},{"id":276926117,"identity":"b6a0ba39-a762-4039-89e5-53b0c8fa1cb1","order_by":5,"name":"Atsushi Yoshida","email":"","orcid":"","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":false,"prefix":"","firstName":"Atsushi","middleName":"","lastName":"Yoshida","suffix":""},{"id":276926118,"identity":"03549000-0b9f-48d8-966b-26bbd90ae4f8","order_by":6,"name":"Reiichi Ishikura","email":"","orcid":"","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":false,"prefix":"","firstName":"Reiichi","middleName":"","lastName":"Ishikura","suffix":""},{"id":276926119,"identity":"6a2a473e-db9e-400b-883e-4e40c73c8617","order_by":7,"name":"Kumiko Ando","email":"","orcid":"","institution":"Kobe City Medical Center General Hospital: Kobe Shiritsu Iryo Center Chuo Shimin Byoin","correspondingAuthor":false,"prefix":"","firstName":"Kumiko","middleName":"","lastName":"Ando","suffix":""}],"badges":[],"createdAt":"2024-02-25 08:24:00","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3987357/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3987357/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s42155-024-00453-7","type":"published","date":"2024-04-25T22:01:02+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":52455273,"identity":"c249fe11-094a-40b4-9976-f04638efd610","added_by":"auto","created_at":"2024-03-11 19:55:20","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":210029,"visible":true,"origin":"","legend":"\u003cp\u003eHow to do the intentional early detachment technique. \u003cstrong\u003ea:\u003c/strong\u003e advancing the detachable coil through the microcatheter until the delivery wire enters without resistance or the microcatheter’s kickback; \u003cstrong\u003eb:\u003c/strong\u003e intentionally detaching the coil within the microcatheter; \u003cstrong\u003ec:\u003c/strong\u003ecompleting the procedure with saline flushing to secure coil placement\u003c/p\u003e","description":"","filename":"figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/fb57c3cf9bcde2c51e649671.png"},{"id":52455270,"identity":"c244e4da-9bbb-4d71-993e-27b1a5b15179","added_by":"auto","created_at":"2024-03-11 19:55:19","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":216307,"visible":true,"origin":"","legend":"\u003cp\u003eUsing coils that cannot be detached within the catheter. \u003cstrong\u003ea:\u003c/strong\u003e advancing only the coil portion of the detachable coil into the microcatheter, ensuring the detachment point (indicated by the red arrow) is just inside the catheter hub; \u003cstrong\u003eb:\u003c/strong\u003e detachment is achieved at the designated point; \u003cstrong\u003ec:\u003c/strong\u003e completing the procedure with saline flushing to secure coil placement\u003c/p\u003e","description":"","filename":"figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/71bab3ee61a07ea49ca8e905.png"},{"id":52456019,"identity":"15ec3c5e-c854-41ab-920a-bbfdd53f4f06","added_by":"auto","created_at":"2024-03-11 20:03:20","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":533239,"visible":true,"origin":"","legend":"\u003cp\u003eClinical Scenarios for Application of the Intentional Early Detachment Technique. \u003cstrong\u003ea: \u003c/strong\u003ecases in which the vascular anatomy exhibits significant tortuosity, challenging the process of pushing a detachable coil's delivery wire through microcatheters; \u003cstrong\u003eb: \u003c/strong\u003ecases in which inadequate system backup results in microcatheter kickbacks during coil placement. Microcatheter kickback challenges the tight placement of detachable coils and poses a potential risk of catheter dislodgment into the mother vessel; \u003cstrong\u003ec:\u003c/strong\u003e cases in which coils are deployed through a 1.3-Fr microcatheter\u003c/p\u003e","description":"","filename":"figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/36204878ea231c66b3e838f2.png"},{"id":52455271,"identity":"85771478-8ecb-4531-b177-f6ff66e26ac2","added_by":"auto","created_at":"2024-03-11 19:55:20","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1098011,"visible":true,"origin":"","legend":"\u003cp\u003eA 69-year-old male presented with an extensive thoracic aortic aneurysm, a right aortic arch, and an isolated left subclavian artery (SCA). Initially, we performed an elephant trunk ascending aorta replacement and reconstructed the cervical branches. Subsequently, we planned for thoracic endovascular aortic repair (TEVAR) to address the aortic arch and descending aortic aneurysm.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ea:\u003c/strong\u003e contrast-enhanced computed tomography revealed a dilated third intercostal artery measuring 4 mm (arrowhead) and a coarse mural thrombus within the aneurysm (star). Embolization of the artery was planned to prevent a type 2 endoleak; \u003cstrong\u003eb:\u003c/strong\u003ea three-dimensional volume-rendering image demonstrated that the highly tortuous third intercostal artery (arrow) anastomosed with the left costocervical trunk, which arises from the left SCA, and that the left vertebral artery (VA) branched off closely to the left costocervical trunk. Considering the risk of peripheral embolization of the VA due to a substantial mural thrombus, we punctured the left brachial artery and accessed this artery from the left SCA; \u003cstrong\u003ec:\u003c/strong\u003e a 1.6-Fr microcatheter (Carnelian Marvel S; Tokai Medical Products, Aichi, Japan) was advanced near the origin of the third intercostal artery, and we attempted to place a 0.014-inch coil (Target XL soft coil; Stryker, Fremont, CA, USA) measuring 5 mm in diameter and 10 cm in length. However, the tortuosity of the pathway was so severe that we were unable to implant the entire coil, and half of it remained within the catheter (dotted line); \u003cstrong\u003ed:\u003c/strong\u003e therefore, the coil was intentionally detached within the catheter and flushed with saline solution for placement; \u003cstrong\u003ee:\u003c/strong\u003e seven additional 0.014-inch coils (six target XL soft coils, one Azur soft 3D coil; Terumo, Tokyo, Japan) were tightly placed using the intentional early detachment technique; \u003cstrong\u003ef:\u003c/strong\u003e final angiogram after TEVAR shows successful aortic repair without any endoleaks\u003c/p\u003e","description":"","filename":"figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/4c09fef89c9e0b6ebe70e2f4.png"},{"id":52455275,"identity":"b2cc5442-332d-4a1f-bb42-56a61671bbb1","added_by":"auto","created_at":"2024-03-11 19:55:20","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1098637,"visible":true,"origin":"","legend":"\u003cp\u003eAn 86-year-old male presented with ascending colonic hemorrhage due to colonic diverticulosis. Transcatheter arterial embolization was performed after hemostatic clipping via colonoscopy was unsuccessful. \u003cstrong\u003ea:\u003c/strong\u003e inferior mesenteric angiography revealed small and significantly tortuous vasa recta of the sigmoid artery (arrow) without contrast extravasation near clipping (arrow); \u003cstrong\u003eb:\u003c/strong\u003e superselective angiography through the vasa recta of the first sigmoid artery (S1) with a 1.6-Fr microcatheter (Carnelian Marvel S; Tokai Medical Products, Aichi, Japan) showed contrast extravasation at the distal end of near clipping (circle); \u003cstrong\u003ec:\u003c/strong\u003ean attempt was made to place a 0.010-inch coil (the COMPLEX SilkySoft iED coil; KANEKA Medix, Osaka, Japan) measuring 1 mm in diameter and 3 cm in length, but the catheter kicked back, and it could not be placed tightly. Consequently, the coil was retrieved without detachment; \u003cstrong\u003ed:\u003c/strong\u003e the same coil was placed using the intentional early detachment technique and was, therefore, placed tightly (arrowhead); \u003cstrong\u003ee:\u003c/strong\u003e five additional 0.011-inch coils (Avenir; Wallaby Medical, Shanghai, China) were placed using the same technique, and the final angiogram did not reveal any contrast extravasation\u003c/p\u003e","description":"","filename":"figure5.png","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/f811576f46e0f9a568203d4d.png"},{"id":52455276,"identity":"39a17f69-ceee-448c-91da-4a601f922407","added_by":"auto","created_at":"2024-03-11 19:55:20","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":1499252,"visible":true,"origin":"","legend":"\u003cp\u003eA 69-year-old male presented with hematemesis. \u003cstrong\u003ea:\u003c/strong\u003e contrast-enhanced computed tomography demonstrated pseudoaneurysm in the gallbladder (circle); \u003cstrong\u003eb:\u003c/strong\u003e angiography from the replaced right hepatic artery revealed two cystic arteries (black arrow and arrowhead); \u003cstrong\u003ec:\u003c/strong\u003e the selection of the right-sided cystic artery (black arrow) was difficult, and a 1.3-Fr microcatheter (DeFrictor Nano; Medico's Hirata, Osaka, Japan) was used. Superselective angiography through the cystic artery showed a pseudoaneurysm (circle);\u003cstrong\u003e d,e: \u003c/strong\u003eadvancing just the coil section of the 0.010-inch Target Nano coil (Stryker, Fremont, CA, USA), which measures 1 mm in diameter and 3 cm in length, into the microcatheter and ensuring that the detachment point is slightly within the catheter hub (white arrowhead), allows for successful detachment;\u003cstrong\u003e f:\u003c/strong\u003e two 0.010-inch coils were placed (white arrow) using the intentional early detachment technique. The left-sided cystic artery was easily selected with a 1.6-Fr catheter (Carnelian MARVEL S; Tokai Medical Products, Aichi, Japan) and embolized with three detachable coils using the standard method; \u003cstrong\u003eg:\u003c/strong\u003e angiography after embolization revealed the complete embolization of the pseudoaneurysm\u003c/p\u003e","description":"","filename":"figure6.png","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/62af12a18b67b1b447151803.png"},{"id":55689460,"identity":"b322f46a-482f-4bb1-92b6-15f34b426df3","added_by":"auto","created_at":"2024-05-01 22:01:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3535878,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3987357/v1/35b336b6-da96-4bb8-b2ea-1deea1aa54ea.pdf"}],"financialInterests":"","formattedTitle":"Enhancing Precision in Vascular Embolization: Evaluating the Effectiveness of the Intentional Early Detachment Technique with Detachable Coils in Complex Cases","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSince their development in 1991, detachable coils have been recognized for their effectiveness and safety in the field of vascular embolization, especially in neurointervention [\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Attached to a delivery wire, these coils can be deployed with control and precision. They have become an important part of the interventional toolkit in cases where precision is essential and downstream nontarget embolization would be catastrophic [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, some situations present unique challenges. In particular, the successful deployment of detachable coils can become challenging when dealing with tortuous vessels or when the backup support of the microcatheter is insufficient. Recent advancements in catheter systems have facilitated the catheterization of tortuous or narrow branches through the use of exceptionally thin microcatheters [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, the narrow inner lumen of these thin catheters limits the types of coils that can be deployed. Especially with 1.3-Fr microcatheters, the use of coils is almost incompatible. To address these challenges, we herein describe an intentional early detachment technique with detachable coils. This novel technique offers a solution for vascular embolization of tortuous or narrow branches that are only accessible with thin microcatheters. By intentionally detaching the detachable coils within the microcatheters and flushing them with saline, interventional radiologists can achieve precise coil placement. We explore the application of the intentional early detachment technique in 11 patients, each presenting unique challenges. Our investigation aims to shed light on the effectiveness and versatility of this technique, providing interventional radiologists with a viable alternative for complex scenarios and ultimately enhancing patient care.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003ePatients\u003c/p\u003e \u003cp\u003e All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Our local Institutional Review Board approved the study (approval number: Zn240208) and waived the need for written informed consent. Between October 2021 and December 2023, 11 embolizations were performed on 11 patients (9 males and 2 females, with a median age of 77 [range, 52\u0026ndash;87] years) using the intentional early detachment technique with detachable coils through a 1.6-Fr or 1.3-Fr microcatheter.\u003c/p\u003e \u003cp\u003eProcedure\u003c/p\u003e \u003cp\u003eIn all cases, this technique was used when it was not possible to embolize the vessel by standard methods of detachable coil placement, and the operator considered embolization with a liquid embolic material inappropriate. We advanced the coil through the microcatheter until the delivery wire could enter without resistance or the microcatheter\u0026rsquo;s kickback, then intentionally detached the coil within the microcatheter, followed by flushing the coil with saline (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Of note, some electrically detachable coils such as the iED coil (KANEKA Medics, Osaka, Japan) and the Target coil (Stryker, Fremont, CA, USA) may not be detachable within the catheter. When using this type of coils, advancing only the coil portion into the microcatheter and ensuring that the detachment point was slightly within the catheter hub allowed for successful detachment (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eEvaluation\u003c/p\u003e \u003cp\u003eThe primary outcome parameter was technical success, defined as when the coils were delivered and placed successfully at the target vessel without migration. Complications and clinical success rates were also evaluated. Clinical success was defined as complete cessation of blood flow at the target vessel by post-embolization angiogram. Complications were evaluated using the Cardiovascular and Interventional Radiological Society of Europe classification system [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. All images were interpreted by two radiologists with more than eight years of experience in diagnostic and interventional radiology. Any disagreements or discrepancies were resolved by consensus.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eDetails of the patient's diseases and the vessels that underwent embolization are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe 11 patients who underwent coil embolization using the intentional early detachment technique with detachable coils.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePatient No /Age /Sex\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEmbolized artery\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEtiology\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCoil: diameter in mm/\u003c/p\u003e \u003cp\u003elength in cm\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNo of coils\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMicrocatheters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eReasons for intentional early detachment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eTechnical/Clinical success\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eComplication\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1/75/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePIPDA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHemorrhage within a pancreatic tumor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTarget XL soft: 6/20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSignificant tortuosity in vascular anatomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2/75/F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDPA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTrue aneurysm due to MALS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTarget nano: 1/2, 1/3(\u0026times;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInadequate system backup\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3/79/F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePIPDA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-EST hemorrhage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSMART Coil: 1/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S 1.3,\u003c/p\u003e \u003cp\u003eMasters HF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eDeployment of coils through a 1.3-Fr catheter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4/83/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eIliolumbar artery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLt-IIAA\u003c/p\u003e \u003cp\u003eEmbolization to prevent T2EL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAvenir: 3/10, 2/8, 2/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInadequate system backup\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5/86/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDiverticular hemorrhage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAvenir: 1.5/3(\u0026times;2),2/4, 2/3(\u0026times;2)\u003c/p\u003e \u003cp\u003eiED coil: 1/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eMasters HF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInadequate system backup\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6/86/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4th LA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2EL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAvenir: 4/20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSignificant tortuosity in vascular anatomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7/76/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2nd LA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2EL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAvenir: 4/20, 3/10, 4/13(\u0026times;2), 5/17(\u0026times;2)\u003c/p\u003e \u003cp\u003eTarget tetra: 3.5/8(\u0026times;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S 1.3,\u003c/p\u003e \u003cp\u003eMasters HF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eDeployment of coils through a 1.3-Fr catheter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8/87/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4th LA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eT2EL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAZUR soft3D: 3/8\u003c/p\u003e \u003cp\u003eAvenir: 4/20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSignificant tortuosity in vascular anatomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9/52/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAIPDA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHemorrhage due to SAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAvenir PICO: 1/2(\u0026times;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S 1.3,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eDeployment of coils through a 1.3-Fr catheter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10/74/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCystic artery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIdiopathic gallbladder bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTarget nano: 1/2(\u0026times;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGuidepost,\u003c/p\u003e \u003cp\u003eDeFrictor Nano,\u003c/p\u003e \u003cp\u003eCarnelian MARVEL S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eDeployment of coils through a 1.3-Fr catheter\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11/69/M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3rd ICA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePreemptive embolization to prevent T2EL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTarget XL: 5/10(\u0026times;2), 4/15(\u0026times;5)\u003c/p\u003e \u003cp\u003eAzur soft3D: 4/10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eCarnelian MARVEL S,\u003c/p\u003e \u003cp\u003eSwift Ninja\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSignificant tortuosity in vascular anatomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eYES/YES\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNO\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003eAIPDA: anterior inferior pancreaticoduodenal artery, PIPDA: posterior inferior pancreaticoduodenal artery, DPA: dorsal pancreatic artery, LA: lumber artery, MALS: median arcuate ligament syndrome, EST: endoscopic sphincterotomy, ICA: intercostal artery, IIAA: internal iliac artery aneurysm, VR: vasa recta, T2EL: type 2 endoleak, SAM: segmental arterial mediolysis,\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003eTarget XL soft/Nano/Tetra (Stryker, Fremont, CA, USA), SMART COIL (Penumbra, Alameda, CA, USA), AVENIR/AVENIR PICO (Wallaby Medical, Shanghai, China), AZUR soft 3D (Terumo, Tokyo, Japan), iED coil (KANEKA Medix, Osaka, Japan)\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003eCarnelian MARVEL S/S 1.3 (Tokai Medical Products, Aichi, Japan), Swift NINJA (SB KAWASUMI, Tokyo, Japan), Masters HF (Asahi Intecc, Aichi, Japan), DeFrictor Nano (Medico's Hirata, Osaka, Japan), Guidepost (Tokai Medical Products)\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe intentional early detachment technique was primarily employed in three distinct clinical scenarios in our study (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The first scenario involved cases in which the vascular anatomy exhibited significant tortuosity, making it challenging to push the delivery wire of a detachable coil through microcatheters (n\u0026thinsp;=\u0026thinsp;4/11). Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e demonstrates a representative case. The second scenario involved situations in which inadequate system backup resulted in microcatheter kickbacks during coil placement. In turn, microcatheter kickback poses challenges in tightly placing detachable coils, and there was also a potential risk of catheter dislodgment into the mother vessel (n\u0026thinsp;=\u0026thinsp;3/11). Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e demonstrates a representative case. The third scenario included cases in which coils were deployed through a 1.3-Fr microcatheter (n\u0026thinsp;=\u0026thinsp;4/11). Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e demonstrates a representative case. Technical and clinical success rates were both 100% in all scenarios.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn all cases, the triaxial system, advancing a small microcatheter from a large microcatheter, was introduced initially as the target arteries appeared to be small and/or tortuous on preprocedural computed tomography images. No coil sticking in the microcatheter, malposition in the target vessel, or migration into non-target vessels occurred. No major complications occurred.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWhen faced with tortuous and meandering vascular pathways, the stiffness of the delivery wires can sometimes impede the complete deployment of detachable coils within the vessel [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. In such a scenario, attempts to use coils from different manufacturers, even those with distinct characteristics, can still pose challenges. Although improving the backup support system is plausible [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], this method has its limitations when navigating thick-diameter catheters through highly tortuous pathways [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. The effectiveness of triaxial systems for navigating through bent pathways has also been reported [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]; however, we used triaxial systems in all our cases and could not place the coils through standard methods. Although embolization with pushable coils using a saline flushing technique has been reported to be effective [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], it may not be suitable in cases where there is a lack of appropriately sized coils that are feasible for large vessel diameters. In Japan, 0.014-inch pushable coils (C-STOPPER coil; Piolax, Kanagawa, Japan) with a diameter of 2.8 mm are available for use with 1.6-Fr microcatheters. However, in vessels with diameters greater than 2.8 mm, the risk of migration is high, limiting the use of pushable coils. In such situations, intentionally detaching a larger-diameter detachable coil within the microcatheter and subsequently flushing it with saline allows for secure placement without the risk of migration (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec, d).\u003c/p\u003e \u003cp\u003eIn cases where the backup support is inadequate, even if the entire length of the coil can be delivered from the catheter, the kickback effect of the microcatheter during placement can prevent tight embolization or lead to catheter deviation into the mother vessel. Under such circumstances, the intentional early detachment technique with the detachable coils can reliably achieve a tight placement. In one of our patients (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e), we initially attempted to place an iED coil measuring 1 mm in diameter and 3 cm in length in the vasa recta of the first sigmoid artery. However, due to difficulties in catheter control and kickback, only loose placement was achieved (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ec). Subsequently, we retrieved the coil and intentionally detached it, followed by flushing with saline, resulting in tight embolization (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003ed).\u003c/p\u003e \u003cp\u003eIn scenarios involving highly tortuous vessel pathways that require the use of ultra-thin microcatheters with a distal tip size of 1.5-Fr or less, these microcatheters are designed for use with liquid embolic materials and are essentially incompatible with coils. Previous reports have mentioned that detachable coils can be used with a 1.5-Fr Marathon microcatheter (Medtronic, Minneapolis, MN, USA) [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The inner lumen at the tip is as small as 0.013 inches, limiting the types of coils that can be used. The inner lumen of microcatheters with a distal tip size of 1.3-Fr, such as the DeFrictor Nano (Medico's Hirata, Osaka, Japan) and Marvel S 1.3 (Tokai Medical Products, Aichi, Japan), is even narrower (0.011 inches). In our experience, standards methods are unsuitable for deploying coils through such narrow lumen microcatheters. This limitation is due to the diameter of the coil\u0026rsquo;s delivery wire being larger than that of the inner lumen of these microcatheters. However, we noticed that, with the so-called 10-coil (0.0095\u0026ndash;0.011 inches in primary diameter), only the coil portion of the detachable coil can be inserted into the catheter, as the primary coil diameter of 10-coil is smaller than that of the lumen of 1.3-Fr microcatheters. Therefore, using a 1.3-Fr microcatheter, we advanced the 10-coil through the microcatheter to a point where the delivery wire could enter without resistance, detached the coil, and subsequently flushed it with saline. This method enabled us to achieve embolization with 10-coils, even through a 1.3-Fr microcatheter. Some electrically detachable coils may not be detachable within the catheter as the detachment point must be energized for detachment and requires surrounding electrolytes, including blood or saline solution. Consequently, detachment within the catheter may not always be feasible using coils such as the iED coil and the Target coil. While the Target coils can sometimes be detached within a 1.6-Fr catheter after multiple detachment attempts, they often cannot be detached within a 1.3-Fr catheter. This is due to the narrow lumen leading to an insufficient amount of electrolytes around the detachment point.\u003c/p\u003e \u003cp\u003eThis study had some limitations. It was a retrospective study conducted at a single facility and included a limited number of patients. Should 0.010-inch pushable coils or 0.014-inch pushable coils with larger diameters become commercially available, they might serve as alternatives to the intentional early detachment technique with detachable coils. In the described technique, detachable coils are employed similarly to how pushable coils would be, meaning that the coil's position cannot be adjusted through repeated retrieval and repositioning during the deployment procedure. Additionally, detachable coils are more expensive than pushable coils. Nonetheless, this study underscores the potential utility of alternative techniques in situations where conventional approaches are limited by vascular anatomy or equipment availability.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study demonstrates the effectiveness of the intentional early detachment technique for detachable coils in complex vascular embolization scenarios. This method has been successfully applied to complex cases, enabling coil placement in challenging vascular embolization scenarios. While its applicability is specific to certain scenarios, this technique offers a valuable option for interventionalists when faced with anatomical or equipment constraints.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eAbbreviations used in this manuscript are limited to figure legends and are not utilized within the main text.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The Institutional Review Board (IRB) of Kobe City Medical Center General Hospital approved the study (approval number: Zn240208), and the need for informed consent was waived.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor this type of study, formal consent was not required.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData sharing is not applicable to this article, as no datasets were generated or analyzed in the current study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo funding was received for conducting this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors contribution:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors contributed to the conception and design\u0026nbsp;of this study. SO, SK, and SA performed material preparation, data collection, and analysis. SO wrote the first draft of the manuscript, and all authors commented on\u0026nbsp;the previous versions of the paper. All authors have read and approved the final version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to thank Editage (www.editage.jp) for English language editing.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eGuglielmi G, Vi\u0026ntilde;uela F, Dion J, Duckwiler G (1991) Electrothrombosis of saccular aneurysms via endovascular approach. Part 2: Preliminary clinical experience. 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Interdiscip Neurosurg 36:101950. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.inat.2023.101950\u003c/span\u003e\u003cspan address=\"10.1016/j.inat.2023.101950\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"cvir-endovascular","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cire","sideBox":"Learn more about [CVIR Endovascular](https://www.springer.com/journal/42155)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/cire/default.aspx","title":"CVIR Endovascular","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Detachable coils, Vascular embolization, Tortuous pathways, Coil detachment, Saline flushing","lastPublishedDoi":"10.21203/rs.3.rs-3987357/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3987357/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eThis study aimed to assess the effectiveness and versatility of an intentional early detachment technique with detachable coils to address challenging vascular embolization scenarios. This novel approach aims to provide interventional radiologists with an alternative method for achieving precise coil placement when standard methods of detachable coil placement are rendered ineffective owing to vascular anatomy or limited available equipment.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e \u003cp\u003eThis was a retrospective study comprising 11 patients (9 males and 2 females; median age, 77 years) who underwent embolization procedures using the intentional early detachment technique via 1.6-Fr or 1.3-Fr microcatheters between October 2021 and December 2023. In this technique, detachable coils were intentionally detached within the microcatheter and placed using saline flushing. Technical success, complications, and clinical success were evaluated.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe technique was applied in three distinct scenarios: tortuous vascular anatomy (4 cases), inadequate system backup (3 cases), and 1.3-Fr microcatheter use (4 cases). The technical and clinical success rates were 100%. No complications were observed, and there were no cases of coil migration or malpositioning.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThe intentional early detachment technique is valuable for interventional radiologists and offers a solution for challenging vascular embolization scenarios. Although its application is limited to specific circumstances, it can significantly enhance coil placement in complex cases, thereby contributing to improved patient care.\u003c/p\u003e","manuscriptTitle":"Enhancing Precision in Vascular Embolization: Evaluating the Effectiveness of the Intentional Early Detachment Technique with Detachable Coils in Complex Cases","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-11 19:55:15","doi":"10.21203/rs.3.rs-3987357/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2024-03-07T08:41:36+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-03-07T08:08:02+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-03-06T10:20:08+00:00","index":"","fulltext":""},{"type":"submitted","content":"CVIR Endovascular","date":"2024-03-04T10:16:58+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"cvir-endovascular","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cire","sideBox":"Learn more about [CVIR Endovascular](https://www.springer.com/journal/42155)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/cire/default.aspx","title":"CVIR Endovascular","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"d75efd85-5d77-40d9-b065-0220a43d5d7c","owner":[],"postedDate":"March 11th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-05-01T22:01:02+00:00","versionOfRecord":{"articleIdentity":"rs-3987357","link":"https://doi.org/10.1186/s42155-024-00453-7","journal":{"identity":"cvir-endovascular","isVorOnly":false,"title":"CVIR Endovascular"},"publishedOn":"2024-04-25 22:01:02","publishedOnDateReadable":"April 25th, 2024"},"versionCreatedAt":"2024-03-11 19:55:15","video":"","vorDoi":"10.1186/s42155-024-00453-7","vorDoiUrl":"https://doi.org/10.1186/s42155-024-00453-7","workflowStages":[]},"version":"v1","identity":"rs-3987357","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3987357","identity":"rs-3987357","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}