Flanged Scleral Fixation: Thermoplastic Properties of Suture Materials and Implications for Flange Geometry

Flanged Scleral Fixation: Thermoplastic Properties of Suture Materials and Implications for Flange Geometry | 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 Flanged Scleral Fixation: Thermoplastic Properties of Suture Materials and Implications for Flange Geometry Melih Parlak, Jens Ulrich Werner, Muhammet Cinar, Armin Wolf This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9260704/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 10 You are reading this latest preprint version Abstract Background: Flanged scleral fixation techniques are increasingly used in the management of intraocular lens dislocation and aphakia. However, complications such as conjunctival erosion and scleral migration remain a concern. Flange geometry may play a critical role in anchoring stability. This study investigates the thermoplastic properties of various suture materials to identify optimal conditions for flange formation. Methods: A disposable electrocautery device with a power supply and tip temperature of 392°C was used for standardised application. Seven suture materials were used: polypropylene (6/0), polyamide 6 (6/0), polyamide 6.6 (6/0), vinylidene fluoride-co-hexafluoropropylene (PVDF) (6/0), polyester (5/0), and polytetrafluoroethylene (PTFE) (5/0 and 6/0). All sutures were heated 0.5, 1, 2, 3, 4, and 5 mm from the distal end and examined in 4 repeat measurements. The prepared flanges were photographed and measured using a digital microscope. The flange dimensions and geometry were assessed. Ratios of flange length to flange width and flange diameter were calculated. Results: All suture materials except polyamide 6.6 (6/0) and PTFE (5/0) formed a flange shape due to the increase in temperature as demonstrated by repeated measurements with a high degree of reproducibility. While polypropylene and PVDF took on a mushroom/rhomboid shape, the flange shape of polyamide 6 and polyester was spherical. The flange geometry of PTFE was funnel-shaped with sharp edges. With increasing duration of heat exposure, the flange length of polypropylene and PVDF increased more significantly than the flange width. Conclusion: Polypropylene and PVDF demonstrate favorable thermoplastic properties for flanged scleral fixation, enabling reproducible flange formation with short heating times. A heating length of approximately 1 mm appears optimal for controlled flange geometry. Further biomechanical and in vivo studies are required to validate clinical performance. flange intraocular lens scleral fixation suture Figures Figure 1 Figure 2 Figure 3 Background In a multitude of surgical contexts, the human sclera serves as a stabilising anchor point for traumatically altered irises or dislocated intraocular lenses. Conventionally, fine suture materials were utilised for this purpose; however, these materials have been observed to pose significant risks, including suture breakage and conjunctival erosion [ 1 ]. Alternatively, flanged scleral fixation can be considered, aiming to be more resistant and durable due to its higher suture strength. While flanged scleral fixation is gaining increasing attention for various surgical indications, complications such as scleral migration, conjunctival erosion, and even endophthalmitis have also been described [ 2 , 3 ]. This downside has not yet been sufficiently investigated. The flange size and geometry are crucial for secure anchoring. This study examines the thermoplastic properties of suture materials to determine the ideal suture material and the optimal heated suture length for flanged scleral fixation. Methods For standardised use, a disposable electrocautery (Bovie Medical, Florida/USA) was operated with a power supply unit that provided the same voltage as the battery originally supplied (I = 3.23 A). A total of seven types of suture material were utilised in the study: polypropylene (6/0; Prolene, Ethicon), vinylidene fluoride-co-hexafluoropropylene (PVDF) (6/0; Pronova, Ethicon), polyamide (6/0; Supramid, Serag-Wiessner), polyamide 6.6 (6/0; Ethilon, Ethicon), multifilament polyester (5/0, Ethibond Excel, Ethicon), and polytetrafluoroethylene (PTFE) (5/0 and 6/0; Seramon, Serag-Wiessner). All sutures were grasped 0.5, 1, 2, 3, 4, and 5 mm from the distal end using microforceps. The free-standing suture segment was then melted up to the forceps by applying heat from a defined distance (1mm). The duration of the heating process was measured. The experiment was repeated four times for each suture material and heating length. The prepared sutures were photographed and measured using a digital microscope (Keyence VHX-7000, Keyence Corp, Osaka/Japan). The flange length, flange width, and flange geometry were examined. Statistics: All data were analysed descriptively, dependent on their scale level, using Microsoft Excel and R for statistical computing (version 4.3.2). For all continuous variables the arithmetic mean, standard deviation (SD), and range were calculated. Graphical representation was based on line charts. Results The cautery tip was found to have a temperature of 392°C. At distances of 1 mm, 1.5 mm, and 2 mm, the temperatures were recorded as 84°C, 44°C, and 28°C, respectively. Consequently, a distance of ca.1 mm was maintained during the heating process. All but two suture materials formed a flange shape due to the increase in temperature. In the case of polyamide 6.6 (Ethilon), crutch-shaped and irregular melting was observed. Despite a melting time of over 10 seconds, no flange formed with 5/0 polytetrafluoroethylene (PTFE; Seramon). Consequently, these sutures were excluded from the microscopic measurements, as no flange, defined as a widening of the suture material, was observed. The shape of the flange varied significantly depending on the type of suture and the heating length (Figures 1 and 2). By contrast, the dimensions of the flange and the application time of the cautery were highly reproducible (Table 1). Figure 1: Flange shape of the tested sutures with a heating length of 1 mm (PVDF: vinylidene fluoride-co-hexafluoropropylene; PTFE: polytetrafluoroethylene) Figure 2: Change in flange geometry with increasing heating length for polypropylene and vinylidene fluoride-co-hexafluoropropylene (PVDF) (from left to right: 0.5, 1, 2, 3, 4, 5 mm) (Top row: polypropylene; bottom row: PVDF) Table 1: Distribution of flange dimensions in different heating lengths Name Material Thickness Suture diameter (mm) Preparation length (mm) Flange length mm (SD) Flange width mm (SD) Flange Width/Length Prolene Polypropylene 6/0 0,1 0,5 0,16 (0,01) 0,25 (0,01) 1,55 1 0,20 (0,01) 0,35 (0,03) 1,51 2 0,23 (0,01) 0,44 (0,01) 1,91 3 0,28 (0,01) 0,51 (0,01) 1,84 4 0,31 (0,01) 0,53 (0,01) 1,72 5 0,35 (0,02) 0,53 (0,01) 1,51 Ethibond Excel Polyester 5/0 0,22 0,5 § § 1 0,24 (0,01) 0,75 (0,09) 3,08 2 0,37 (0,05) 0,47 (0,08) 1,27 3 0,46 (0,01) 0,52 (0,03) 1,11 4 0,51 (0,01) 0,61 (0,03) 1,2 5 0,58 (0,04) 0,63 (0,03) 1,09 Pronova Vinylidene fluoride-co-hexafluoropropylene (PVDF) 6/0 0,11 0,5 0,14 (0,02) 0,26 (0,03) 1,93 1 0,18 (0,01) 0,31 (0,01) 1,69 2 0,34 (0,02) 0,32 (0,01) 0,94 3 0,45 (0,03) 0,33 (0,01) 0,74 4 0,59 (0,01) 0,35 (0,01) 0,6 5 0,69 (0,03) 0,37 (0,01) 0,54 Supramid Polyamid 5/0 0,14 0,5 0,28 (0,04) 0,29 (0,03) 1,02 1 0,31 (0,01) 0,31 (0,01) 1,01 2 0,40 (0,01) 0,40 (0,01) 0,99 3 0,47 (0,01) 0,46 (0,01) 0,98 4 0,52 (0,02) 0,51 (0,02) 0,98 5 0,55 (0,01) 0,55 (0,01) 1 Seramon Polytetrafluoroethylen (PTFE) 6/0 0,14 0,5 § § 1 0,22 (0,01) 0,38 (0.02) 1,77 2 0,33 (0,02) 0,39 (0,01) 1,2 3 0,45 (0,02) 0,40 (0,01) 0,88 4 0,49 (0,04) 0,40 (0,03) 0,82 5 0,55 (0,03) 0,43 (0,01) 0,78 (§: There was no flange formation after heat exposure.) Polypropylene showed a mushroom-shaped flange at heating distance of 0.5 to 2 mm, while it changed to a rhomboid shape as the heating distance increased. The heating time was relatively short, ranging between 1 and 4 seconds. The highest ratio between flange width and flange length was achieved with 2 mm of prepared suture material (Fig. 3). Figure 3: Graphical representation of the heating time and geometric indices of the flanges at various preparation lengths. (A: Flange width-to-length ratio; B: Ratio of flange width to suture diameter; C: heating time) The heating time for PVDF was similarly favourable to that for polypropylene. However, the two filaments differed in terms of flange shape. The flange length increased more significantly than the flange width for PVDF. The largest width-to-length ratio was achieved with a heating distance of 0.5 mm. Figure 2 shows the different flange shapes of polypropylene and PVDF depending on the distance from the heated material. The flange shape for polyamide (Supramid) was spherical in all lengths of heated material and had a very smooth surface. From a heating length of 3 mm, thermal damage was observed in the form of discolouration of the flange tip and a rougher surface. As the only multifilament suture, the heating process for polyester differed from that of monofilament sutures. When gripped with forceps, the suture split at the tip, so that short-distance heating did not produce a flange. From a heating length of 1 mm, a spherical flange with a smooth, round surface formed. The flange became larger with increasing heating length, but not wider, so that the maximum flange width was achieved with 1 mm heating. Polytetrafluoroethylene (PTFE) was the most heat-resistant suture material. After prolonged heating, 6/0 PTFE formed a funnel-shaped flange. The width differed only slightly. All flanges were sharp-edged at the end of the suture. In contrast, even after prolonged heating, only a limited distance of 1–2 mm could be melted with 5/0 PTFE, and no flange formed. Discussion The use of flanged suture material for scleral fixation is becoming increasingly important in the treatment of dislocated lenses, aphakia, and traumatic iris changes. To avoid complications such as conjunctival erosion, scleral migration, and endophthalmitis, it is crucial to achieve stable intrascleral anchoring and a practical, reproducible application method. The present study clearly demonstrates the differences in the thermoplastic properties of various suture materials. Among the materials tested, polypropylene and PVDF in particular exhibited favourable thermal and geometric properties. Both materials formed reproducibly stable flanges with a short melting time and homogeneous shape. Polypropylene produced a mushroom-shaped flange with a broad base, which, in theory, should ensure high tissue resistance to retraction into the vitreous cavity. The most commonly used suture material in the literature is polypropylene. To the best of our knowledge, no biomechanical studies have been conducted on the pull-out force of flanged polypropylene scleral sutures to date. On the other hand, PVDF exhibited a more elongated, rhomboid flange shape. The width-to-length ratio for heating lengths of 0.5 and 1 mm was similar to that of polypropylene. From a heating length of 2 mm onwards, the flange length increased significantly more than the width. This potentially allows deeper embedding in the sclera but may entail a slightly higher risk of migration. Ma et al. conducted a biomechanical study investigating the pull-out resistance of intraocular lenses (IOLs) with flanged scleral fixation [ 4 ]. The PVDF IOL haptic with a heating distance of 1 mm showed the highest pull-out resistance compared to PMMA haptics. At the same time, PVDF also exhibited the greatest flange width at the same heating length, ultimately confirming the importance of flange geometry. Polyamide exhibited a very smooth, spherical flange shape, which, thanks to its uniform surface, is expected to be well tolerated by tissue. However, prolonged heating led to thermal damage, including discolouration, which could mean an increased risk of structural weakening or biological incompatibility. Polyester was the only multifilament material examined. It exhibited significant variability during the melting process; a spherical flange only formed at a heating length of 2 mm or more. In classic suturing techniques, the advantage of polyester lies in its stable knot hold, high knot security, and flexible and pliable handling [ 5 ]. However, these properties may make it difficult to insert the suture intraocularly into a cannula. Due to this and the splicing behaviour at the forceps contact point, polyester appears to be of limited suitability for flange formation. As expected, polytetrafluoroethylene (PTFE) proved to be highly heat-resistant, requiring more than three times the heating time of the other filaments to reach a length of 1 mm. While 6/0 PTFE formed a funnel-shaped flange after prolonged heating, 5/0 PTFE showed virtually no flange formation. The pronounced thermal resistance of this material thus limits its practical applicability for flanged scleral fixation. In addition, the sharp-edged flange shape could promote tissue erosion. So far, the data on flanged scleral fixation has been based primarily on surgical results. Kronschlaeger et al published a study on the melting behaviour of polypropylene that yielded results similar to those presented in this paper [ 6 ]. However, other suture materials were not examined. This study is the first to provide a systematic experimental analysis of the physical properties of materials with regard to flange formation. Which suture material is ideal for flanged scleral fixation? What is the correct heating length? These questions can only be answered approximately based on this data, since biomechanical tensile tests were not part of this study. Polypropylene and PVDF appear to be the most suitable suture materials. Both require a short heating time and produce the optimal flange shape when the heating length is 1–2 mm. To ensure the flange can be securely positioned intrasclerally, we recommend using a suture with a heating length of 1 mm. A greater flange width, achievable with a heating length of 2–3 mm, may be advantageous for the internal anchoring of other intraocular structures, such as the iris, capsular tension ring, and intraocular lenses. Limitations of the study include the fact that only thermoplastic properties were examined in vitro. Mechanical stress tests, ageing effects, and biological reactions of the tissue could not be taken into account. Furthermore, it cannot be ruled out that the flange shape is influenced by real surgical conditions such as contact angle, cooling by tissue, or material tension. In conclusion, it can be stated that polypropylene and PVDF provide the best conditions for safe and reproducible flange formation. Both materials enable controlled shaping with a short heating time and exhibit stable geometric properties. High reproducibility and short melting times are particularly important to us, as creating a flange is considerably more difficult under clinical conditions than under laboratory conditions. Additionally, heat exposure must not cause collateral damage to the ocular surface; therefore, the importance of creating the flange in the simplest way possible from a technical standpoint should not be underestimated. Further investigations, particularly biomechanical and histological analyses, are required in order to transfer the findings obtained in vitro to the clinical context and further reduce the risk of long-term complications such as conjunctival erosion or endophthalmitis. Declarations Statement of Ethics The study was conducted in accordance with the Declaration of Helsinki. Due to the experimental study design, no statement from the ethics committee was required. There was no patient contact. Clinical data were not collected. Conflict of Interest Statement All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript. Melih Parlak and Jens Ulrich Werner received speaker fees from Bayer and Novartis. Prof. Dr. Armin Wolf received research grants and study fees from Allergan, Boehringer Ingelheim, Bayer, Alimera, Novartis, Oertli, and Roche, and consulting honoraria and travel fees from Alimera, Allergan, Bayer, Boehringer Ingelheim, Novartis, Oertli, Roche, and Zeiss. For the remaining authors, none conflict of interests or fundings were declared. Funding Sources This study was not supported by any sponsor or funder. Author Contributions All authors made substantial contributions to the conception, acquisition, analysis, and interpretation of the work. Melih Parlak and Jens Ulrich Werner drafted the paper. All authors participated in the experimental design and implementation. Armin Wolf interpreted the data. All authors revised it critically for important intellectual content and approved the final version for publication and agreed to take responsibility for all aspects of the work, including ensuring that questions about the accuracy or integrity of any part of the work are appropriately investigated and resolved. Data Availability Statement All data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author. Acknowledgements Not applicable References Lee J, Lee J, Lee CS, Kim M, Byeon SH, Kim SS, Kang HG (2024) Factors predicting redislocation or suture break in eyes after scleral-fixated intraocular lens. J Cataract Refract Surg 50:1037-1044. https://doi.org/10.1097/j.jcrs.0000000000001497 Pakravan P, Patel V, Chau V, Rohowetz L, Lai J, Fan KC, Al-Khersan H, Melo IM, Muni RH, Tsao SW, Kaplan R, Jung JJ, Hoyek S, Patel NA, Kuriyan AE, Laura DM, Mantopoulos D, Syed ZA, Yannuzzi NA (2023) Haptic Erosion Following Sutureless Scleral-fixated Intraocular Lens Placement. Ophthalmol Retina 7:333-337. https://doi.org/10.1016/j.oret.2022.10.015 Werner L (2021) Flange erosion/exposure and the risk for endophthalmitis. J Cataract Refract Surg 47:1109-1110. https://doi.org/10.1097/j.jcrs.0000000000000738 Ma KK, Yuan A, Sharifi S, Pineda R. (2021) A Biomechanical Study of Flanged Intrascleral Haptic Fixation of Three-Piece Intraocular Lenses. Am J Ophthalmol 227:45-52. https://doi.org/10.1016/j.ajo.2021.02.021. Elgohary DH, Saad MA, Salem MM, Sherazy EH, Khalifa TF (2025) Assessment the properties of various surgical sutures. Sci Rep 15:33330. https://doi.org/10.1038/s41598-025-20311-3 Kronschläger M, Blouin S, Ruiss M, Findl O (2022) Attaining optimal flange size with 5-0 and 6-0 polypropylene sutures for scleral fixation. J Cataract Refract Surg 48:1342-1345. https://doi.org/10.1097/j.jcrs.0000000000001024 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 05 May, 2026 Reviews received at journal 07 Apr, 2026 Reviewers agreed at journal 07 Apr, 2026 Reviews received at journal 05 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 01 Apr, 2026 Reviewers invited by journal 31 Mar, 2026 Editor assigned by journal 31 Mar, 2026 Submission checks completed at journal 31 Mar, 2026 First submitted to journal 29 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. 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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-9260704","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":617729307,"identity":"69035ce5-c0de-438f-9f4e-4c50a5c2e9cf","order_by":0,"name":"Melih Parlak","email":"data:image/png;base64,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","orcid":"","institution":"Ulm University Medical School","correspondingAuthor":true,"prefix":"","firstName":"Melih","middleName":"","lastName":"Parlak","suffix":""},{"id":617729309,"identity":"94f827f0-046c-4d9e-81bf-03c6373e4563","order_by":1,"name":"Jens Ulrich Werner","email":"","orcid":"","institution":"Ulm University Medical School","correspondingAuthor":false,"prefix":"","firstName":"Jens","middleName":"Ulrich","lastName":"Werner","suffix":""},{"id":617729311,"identity":"e42cea7b-8e50-4f26-a731-9800e7f29d24","order_by":2,"name":"Muhammet Cinar","email":"","orcid":"","institution":"Ulm University Medical School","correspondingAuthor":false,"prefix":"","firstName":"Muhammet","middleName":"","lastName":"Cinar","suffix":""},{"id":617729312,"identity":"0e3568c5-3e9b-43e9-8a29-bde33f12e3dc","order_by":3,"name":"Armin Wolf","email":"","orcid":"","institution":"Ulm University Medical School","correspondingAuthor":false,"prefix":"","firstName":"Armin","middleName":"","lastName":"Wolf","suffix":""}],"badges":[],"createdAt":"2026-03-29 19:25:49","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9260704/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9260704/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106198512,"identity":"ff0a61d0-dc25-464a-a60c-3ded4fb181ab","added_by":"auto","created_at":"2026-04-06 01:41:09","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":998587,"visible":true,"origin":"","legend":"\u003cp\u003eFlange shape of the tested sutures with a heating length of 1 mm\u003c/p\u003e\n\u003cp\u003e(PVDF: vinylidene fluoride-co-hexafluoropropylene; PTFE: polytetrafluoroethylene)\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9260704/v1/a8e2495ab00c558cc4a321b5.png"},{"id":106402462,"identity":"b94a7eb8-5189-4178-b184-a9df3aaf0e79","added_by":"auto","created_at":"2026-04-08 09:12:05","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":646739,"visible":true,"origin":"","legend":"\u003cp\u003eChange in flange geometry with increasing heating length for polypropylene and vinylidene fluoride-co-hexafluoropropylene (PVDF)\u003c/p\u003e\n\u003cp\u003e(from left to right: 0.5, 1, 2, 3, 4, 5 mm)\u003c/p\u003e\n\u003cp\u003e(Top row: polypropylene; bottom row: PVDF)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-9260704/v1/7f222699384aa09f087d998a.png"},{"id":106198514,"identity":"71176ea9-d637-4aee-a67c-90d7800bdd04","added_by":"auto","created_at":"2026-04-06 01:41:09","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":116361,"visible":true,"origin":"","legend":"\u003cp\u003eGraphical representation of the heating time and geometric indices of the flanges at various preparation lengths. (A: Flange width-to-length ratio; B: Ratio of flange width to suture diameter; C: heating time)\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-9260704/v1/bea4a22d0f11a1c90f05ce6e.png"},{"id":106959379,"identity":"a6258467-934b-4e43-b081-a88d3c147b89","added_by":"auto","created_at":"2026-04-15 09:07:32","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2090963,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9260704/v1/971b828a-327f-4080-98f8-689f5ce8418b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Flanged Scleral Fixation: Thermoplastic Properties of Suture Materials and Implications for Flange Geometry","fulltext":[{"header":"Background","content":"\u003cp\u003eIn a multitude of surgical contexts, the human sclera serves as a stabilising anchor point for traumatically altered irises or dislocated intraocular lenses. Conventionally, fine suture materials were utilised for this purpose; however, these materials have been observed to pose significant risks, including suture breakage and conjunctival erosion [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAlternatively, flanged scleral fixation can be considered, aiming to be more resistant and durable due to its higher suture strength. While flanged scleral fixation is gaining increasing attention for various surgical indications, complications such as scleral migration, conjunctival erosion, and even endophthalmitis have also been described [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. This downside has not yet been sufficiently investigated.\u003c/p\u003e \u003cp\u003eThe flange size and geometry are crucial for secure anchoring. This study examines the thermoplastic properties of suture materials to determine the ideal suture material and the optimal heated suture length for flanged scleral fixation.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eFor standardised use, a disposable electrocautery (Bovie Medical, Florida/USA) was operated with a power supply unit that provided the same voltage as the battery originally supplied (I\u0026thinsp;=\u0026thinsp;3.23 A).\u003c/p\u003e \u003cp\u003eA total of seven types of suture material were utilised in the study: polypropylene (6/0; Prolene, Ethicon), vinylidene fluoride-co-hexafluoropropylene (PVDF) (6/0; Pronova, Ethicon), polyamide (6/0; Supramid, Serag-Wiessner), polyamide 6.6 (6/0; Ethilon, Ethicon), multifilament polyester (5/0, Ethibond Excel, Ethicon), and polytetrafluoroethylene (PTFE) (5/0 and 6/0; Seramon, Serag-Wiessner).\u003c/p\u003e \u003cp\u003eAll sutures were grasped 0.5, 1, 2, 3, 4, and 5 mm from the distal end using microforceps. The free-standing suture segment was then melted up to the forceps by applying heat from a defined distance (1mm). The duration of the heating process was measured. The experiment was repeated four times for each suture material and heating length. The prepared sutures were photographed and measured using a digital microscope (Keyence VHX-7000, Keyence Corp, Osaka/Japan). The flange length, flange width, and flange geometry were examined.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStatistics:\u003c/h2\u003e \u003cp\u003eAll data were analysed descriptively, dependent on their scale level, using Microsoft Excel and R for statistical computing (version 4.3.2). For all continuous variables the arithmetic mean, standard deviation (SD), and range were calculated. Graphical representation was based on line charts.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe cautery tip was found to have a temperature of 392\u0026deg;C. At distances of 1 mm, 1.5 mm, and 2 mm, the temperatures were recorded as 84\u0026deg;C, 44\u0026deg;C, and 28\u0026deg;C, respectively. Consequently, a distance of ca.1 mm was maintained during the heating process. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll but two suture materials formed a flange shape due to the increase in temperature. In the case of polyamide 6.6 (Ethilon), crutch-shaped and irregular melting was observed. Despite a melting time of over 10 seconds, no flange formed with 5/0 polytetrafluoroethylene (PTFE; Seramon). Consequently, these sutures were excluded from the microscopic measurements, as no flange, defined as a widening of the suture material, was observed.\u003c/p\u003e\n\u003cp\u003eThe shape of the flange varied significantly depending on the type of suture and the heating length (Figures 1 and 2). By contrast, the dimensions of the flange and the application time of the cautery were highly reproducible (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 1:\u003c/strong\u003e Flange shape of the tested sutures with a heating length of 1 mm\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e(PVDF: vinylidene fluoride-co-hexafluoropropylene; PTFE: polytetrafluoroethylene)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 2:\u0026nbsp;\u003c/strong\u003e Change in flange geometry with increasing heating length for polypropylene and vinylidene fluoride-co-hexafluoropropylene (PVDF)\u003c/p\u003e\n\u003cp\u003e(from left to right: 0.5, 1, 2, 3, 4, 5 mm)\u003c/p\u003e\n\u003cp\u003e(Top row: polypropylene; bottom row: PVDF)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1:\u0026nbsp;\u003c/strong\u003eDistribution of flange dimensions in different heating lengths\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"633\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003eName\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eMaterial\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eThickness\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eSuture diameter (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003ePreparation length (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eFlange length\u0026nbsp;\u003c/p\u003e\n \u003cp\u003emm (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003eFlange width\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;mm (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eFlange Width/Length\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003eProlene\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003ePolypropylene\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e6/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e0,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,16 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,25 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,20 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,35 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,23 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,44 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,91\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,28 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,51 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,84\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,31 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,53 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,35 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,53 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003eEthibond Excel\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003ePolyester\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e5/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0,22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e0,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026sect;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026sect;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,24 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,75 (0,09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e3,08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,37 (0,05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,47 (0,08)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,27\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,46 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,52 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,51 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,61 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,58 (0,04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,63 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003ePronova\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eVinylidene fluoride-co-hexafluoropropylene (PVDF)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e6/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0,11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e0,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,14 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,26 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,93\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,18 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,31 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,34 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,32 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,45 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,33 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,59 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,35 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,69 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,37 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,54\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003eSupramid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003ePolyamid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e5/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0,14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e0,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,28 (0,04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,29 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,02\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,31 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,31 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,40 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,40 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,99\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,47 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,46 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,98\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,52 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,51 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,98\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,55 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,55 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 56px;\"\u003e\n \u003cp\u003eSeramon\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003ePolytetrafluoroethylen (PTFE)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e6/0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" rowspan=\"6\" valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0,14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e0,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026sect;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026sect;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,22 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,38 (0.02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,77\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,33 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,39 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e1,2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,45 (0,02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,40 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,49 (0,04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,40 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,55 (0,03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 85px;\"\u003e\n \u003cp\u003e0,43 (0,01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0,78\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e(\u0026sect;: There was no flange formation after heat exposure.)\u003c/p\u003e\n\u003cp\u003ePolypropylene showed a mushroom-shaped flange at heating distance of 0.5 to 2 mm, while it changed to a rhomboid shape as the heating distance increased. The heating time was relatively short, ranging between 1 and 4 seconds. The highest ratio between flange width and flange length was achieved with 2 mm of prepared suture material (Fig. 3).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure 3:\u003c/strong\u003e Graphical representation of the heating time and geometric indices of the flanges at various preparation lengths. (A: Flange width-to-length ratio; B: Ratio of flange width to suture diameter; C: heating time)\u003c/p\u003e\n\u003cp\u003eThe heating time for PVDF was similarly favourable to that for polypropylene. However, the two filaments differed in terms of flange shape. The flange length increased more significantly than the flange width for PVDF. The largest width-to-length ratio was achieved with a heating distance of 0.5 mm. Figure 2 shows the different flange shapes of polypropylene and PVDF depending on the distance from the heated material.\u003c/p\u003e\n\u003cp\u003eThe flange shape for polyamide (Supramid) was spherical in all lengths of heated material and had a very smooth surface. From a heating length of 3 mm, thermal damage was observed in the form of discolouration of the flange tip and a rougher surface.\u003c/p\u003e\n\u003cp\u003eAs the only multifilament suture, the heating process for polyester differed from that of monofilament sutures. When gripped with forceps, the suture split at the tip, so that short-distance heating did not produce a flange. From a heating length of 1 mm, a spherical flange with a smooth, round surface formed. The flange became larger with increasing heating length, but not wider, so that the maximum flange width was achieved with 1 mm heating.\u003c/p\u003e\n\u003cp\u003ePolytetrafluoroethylene (PTFE) was the most heat-resistant suture material. After prolonged heating, 6/0 PTFE formed a funnel-shaped flange. The width differed only slightly. All flanges were sharp-edged at the end of the suture. In contrast, even after prolonged heating, only a limited distance of 1\u0026ndash;2 mm could be melted with 5/0 PTFE, and no flange formed.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe use of flanged suture material for scleral fixation is becoming increasingly important in the treatment of dislocated lenses, aphakia, and traumatic iris changes. To avoid complications such as conjunctival erosion, scleral migration, and endophthalmitis, it is crucial to achieve stable intrascleral anchoring and a practical, reproducible application method. The present study clearly demonstrates the differences in the thermoplastic properties of various suture materials.\u003c/p\u003e \u003cp\u003eAmong the materials tested, polypropylene and PVDF in particular exhibited favourable thermal and geometric properties. Both materials formed reproducibly stable flanges with a short melting time and homogeneous shape. Polypropylene produced a mushroom-shaped flange with a broad base, which, in theory, should ensure high tissue resistance to retraction into the vitreous cavity. The most commonly used suture material in the literature is polypropylene. To the best of our knowledge, no biomechanical studies have been conducted on the pull-out force of flanged polypropylene scleral sutures to date.\u003c/p\u003e \u003cp\u003eOn the other hand, PVDF exhibited a more elongated, rhomboid flange shape. The width-to-length ratio for heating lengths of 0.5 and 1 mm was similar to that of polypropylene. From a heating length of 2 mm onwards, the flange length increased significantly more than the width. This potentially allows deeper embedding in the sclera but may entail a slightly higher risk of migration. Ma et al. conducted a biomechanical study investigating the pull-out resistance of intraocular lenses (IOLs) with flanged scleral fixation [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. The PVDF IOL haptic with a heating distance of 1 mm showed the highest pull-out resistance compared to PMMA haptics. At the same time, PVDF also exhibited the greatest flange width at the same heating length, ultimately confirming the importance of flange geometry.\u003c/p\u003e \u003cp\u003ePolyamide exhibited a very smooth, spherical flange shape, which, thanks to its uniform surface, is expected to be well tolerated by tissue. However, prolonged heating led to thermal damage, including discolouration, which could mean an increased risk of structural weakening or biological incompatibility.\u003c/p\u003e \u003cp\u003ePolyester was the only multifilament material examined. It exhibited significant variability during the melting process; a spherical flange only formed at a heating length of 2 mm or more. In classic suturing techniques, the advantage of polyester lies in its stable knot hold, high knot security, and flexible and pliable handling [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, these properties may make it difficult to insert the suture intraocularly into a cannula. Due to this and the splicing behaviour at the forceps contact point, polyester appears to be of limited suitability for flange formation.\u003c/p\u003e \u003cp\u003eAs expected, polytetrafluoroethylene (PTFE) proved to be highly heat-resistant, requiring more than three times the heating time of the other filaments to reach a length of 1 mm. While 6/0 PTFE formed a funnel-shaped flange after prolonged heating, 5/0 PTFE showed virtually no flange formation. The pronounced thermal resistance of this material thus limits its practical applicability for flanged scleral fixation. In addition, the sharp-edged flange shape could promote tissue erosion.\u003c/p\u003e \u003cp\u003eSo far, the data on flanged scleral fixation has been based primarily on surgical results. Kronschlaeger et al published a study on the melting behaviour of polypropylene that yielded results similar to those presented in this paper [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. However, other suture materials were not examined. This study is the first to provide a systematic experimental analysis of the physical properties of materials with regard to flange formation. Which suture material is ideal for flanged scleral fixation? What is the correct heating length? These questions can only be answered approximately based on this data, since biomechanical tensile tests were not part of this study. Polypropylene and PVDF appear to be the most suitable suture materials. Both require a short heating time and produce the optimal flange shape when the heating length is 1\u0026ndash;2 mm. To ensure the flange can be securely positioned intrasclerally, we recommend using a suture with a heating length of 1 mm. A greater flange width, achievable with a heating length of 2\u0026ndash;3 mm, may be advantageous for the internal anchoring of other intraocular structures, such as the iris, capsular tension ring, and intraocular lenses.\u003c/p\u003e \u003cp\u003eLimitations of the study include the fact that only thermoplastic properties were examined in vitro. Mechanical stress tests, ageing effects, and biological reactions of the tissue could not be taken into account. Furthermore, it cannot be ruled out that the flange shape is influenced by real surgical conditions such as contact angle, cooling by tissue, or material tension.\u003c/p\u003e \u003cp\u003eIn conclusion, it can be stated that polypropylene and PVDF provide the best conditions for safe and reproducible flange formation. Both materials enable controlled shaping with a short heating time and exhibit stable geometric properties. High reproducibility and short melting times are particularly important to us, as creating a flange is considerably more difficult under clinical conditions than under laboratory conditions. Additionally, heat exposure must not cause collateral damage to the ocular surface; therefore, the importance of creating the flange in the simplest way possible from a technical standpoint should not be underestimated.\u003c/p\u003e \u003cp\u003eFurther investigations, particularly biomechanical and histological analyses, are required in order to transfer the findings obtained in vitro to the clinical context and further reduce the risk of long-term complications such as conjunctival erosion or endophthalmitis.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eStatement of Ethics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted in accordance with the Declaration of Helsinki. Due to the experimental study design, no statement from the ethics committee was required. There was no patient contact. Clinical data were not collected.\u003c/p\u003e\n\u003cp id=\"_Toc472330565\"\u003e\u0026nbsp;\u003cstrong\u003eConflict of Interest Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript. Melih Parlak and Jens Ulrich Werner received speaker fees from Bayer and Novartis. Prof. Dr. Armin Wolf received research grants and study fees from Allergan, Boehringer Ingelheim, Bayer, Alimera, Novartis, Oertli, and Roche, and consulting honoraria and travel fees from Alimera, Allergan, Bayer, Boehringer Ingelheim, Novartis, Oertli, Roche, and Zeiss. For the remaining authors, none conflict of interests or fundings were declared.\u003c/p\u003e\n\u003cp id=\"_Toc472330566\"\u003e\u003cstrong\u003eFunding Sources\u003c/strong\u003e\u003c/p\u003e\n\u003cp id=\"_Toc472330568\"\u003eThis study was not supported by any sponsor or funder.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors made substantial contributions to the conception, acquisition, analysis, and interpretation of the work. Melih Parlak and Jens Ulrich Werner drafted the paper. All authors participated in the experimental design and implementation. Armin Wolf interpreted the data. All authors revised it critically for important intellectual content and approved the final version for publication and agreed to take responsibility for all aspects of the work, including ensuring that questions about the accuracy or integrity of any part of the work are appropriately investigated and resolved.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eLee J, Lee J, Lee CS, Kim M, Byeon SH, Kim SS, Kang HG (2024) Factors predicting redislocation or suture break in eyes after scleral-fixated intraocular lens. J Cataract Refract Surg 50:1037-1044.\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ehttps://doi.org/10.1097/j.jcrs.0000000000001497\u003c/p\u003e\n\u003col start=\"2\"\u003e\n \u003cli\u003ePakravan P, Patel V, Chau V, Rohowetz L, Lai J, Fan KC, Al-Khersan H, Melo IM, Muni RH, Tsao SW, Kaplan R, Jung JJ, Hoyek S, Patel NA, Kuriyan AE, Laura DM, Mantopoulos D, Syed ZA, Yannuzzi NA (2023) Haptic Erosion Following Sutureless Scleral-fixated Intraocular Lens Placement. Ophthalmol Retina 7:333-337.\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ehttps://doi.org/10.1016/j.oret.2022.10.015\u003c/p\u003e\n\u003col start=\"3\"\u003e\n \u003cli\u003eWerner L (2021) Flange erosion/exposure and the risk for endophthalmitis. J Cataract Refract Surg 47:1109-1110.\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ehttps://doi.org/10.1097/j.jcrs.0000000000000738\u003c/p\u003e\n\u003col start=\"4\"\u003e\n \u003cli\u003eMa KK, Yuan A, Sharifi S, Pineda R. (2021) A Biomechanical Study of Flanged Intrascleral Haptic Fixation of Three-Piece Intraocular Lenses. Am J Ophthalmol\u0026nbsp;227:45-52. \u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ehttps://doi.org/10.1016/j.ajo.2021.02.021.\u003c/p\u003e\n\u003col start=\"5\"\u003e\n \u003cli\u003eElgohary DH, Saad MA, Salem MM, Sherazy EH, Khalifa TF (2025) Assessment the properties of various surgical sutures. Sci Rep 15:33330.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ehttps://doi.org/10.1038/s41598-025-20311-3\u003c/p\u003e\n\u003col start=\"6\"\u003e\n \u003cli\u003eKronschl\u0026auml;ger M, Blouin S, Ruiss M, Findl O (2022) Attaining optimal flange size with \u0026nbsp; 5-0 and 6-0 polypropylene sutures for scleral fixation. J Cataract Refract Surg 48:1342-1345.\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ehttps://doi.org/10.1097/j.jcrs.0000000000001024\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"flange, intraocular lens, scleral fixation, suture","lastPublishedDoi":"10.21203/rs.3.rs-9260704/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9260704/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Flanged scleral fixation techniques are increasingly used in the management of intraocular lens dislocation and aphakia. However, complications such as conjunctival erosion and scleral migration remain a concern. Flange geometry may play a critical role in anchoring stability. This study investigates the thermoplastic properties of various suture materials to identify optimal conditions for flange formation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA disposable electrocautery device with a power supply and tip temperature of 392°C was used for standardised application. Seven suture materials were used: polypropylene (6/0), polyamide 6 (6/0), polyamide 6.6 (6/0), vinylidene fluoride-co-hexafluoropropylene (PVDF) (6/0), polyester (5/0), and polytetrafluoroethylene (PTFE) (5/0 and 6/0). All sutures were heated 0.5, 1, 2, 3, 4, and 5 mm from the distal end and examined in 4 repeat measurements. The prepared flanges were photographed and measured using a digital microscope. The flange dimensions and geometry were assessed. Ratios of flange length to flange width and flange diameter were calculated.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eAll suture materials except polyamide 6.6 (6/0) and PTFE (5/0) formed a flange shape due to the increase in temperature as demonstrated by repeated measurements with a high degree of reproducibility. While polypropylene and PVDF took on a mushroom/rhomboid shape, the flange shape of polyamide 6 and polyester was spherical. The flange geometry of PTFE was funnel-shaped with sharp edges. With increasing duration of heat exposure, the flange length of polypropylene and PVDF increased more significantly than the flange width.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003ePolypropylene and PVDF demonstrate favorable thermoplastic properties for flanged scleral fixation, enabling reproducible flange formation with short heating times. A heating length of approximately 1 mm appears optimal for controlled flange geometry. Further biomechanical and in vivo studies are required to validate clinical performance.\u003c/p\u003e","manuscriptTitle":"Flanged Scleral Fixation: Thermoplastic Properties of Suture Materials and Implications for Flange Geometry","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-06 01:41:05","doi":"10.21203/rs.3.rs-9260704/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-05T07:43:31+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-07T13:24:09+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"14592651589554805550800944814252176848","date":"2026-04-07T13:08:36+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-05T07:38:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"23981856231452289479522545538016681284","date":"2026-04-02T18:45:22+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"22328648077121213743442336286754750403","date":"2026-04-01T07:48:05+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-31T19:43:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-31T07:22:17+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-31T07:22:11+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Ophthalmology","date":"2026-03-29T19:07:14+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-ophthalmology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"boph","sideBox":"Learn more about [BMC Ophthalmology](http://bmcophthalmol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/boph","title":"BMC Ophthalmology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e639139a-2651-4e4a-b0d7-73915abd157e","owner":[],"postedDate":"April 6th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-05T07:43:31+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T07:55:01+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-06 01:41:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9260704","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9260704","identity":"rs-9260704","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}