Development of a novel fluorescent gauze using indocyanine green

Development of a novel fluorescent gauze using indocyanine green | 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 Article Development of a novel fluorescent gauze using indocyanine green Takeshi Urade, Shinobu Tsuchida, Kentaro Oji, Yoshiaki Fujiwara, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4519399/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 25 Mar, 2025 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract Gauzes are used in various ways, including wiping blood, compressing organs, and as markers during surgery. However, losing gauze during surgery can lead to pieces being left inside the body, causing time-consuming searches and unnecessary radiation exposure. To address this, we developed a fluorescent gauze using indocyanine green (ICG), which fluoresces under near-infrared (NIR) light. This study aimed to evaluate the fluorescence intensity (FI) of the gauze and confirm its fluorescence in a porcine abdominal cavity. We dissolved 25 mg of ICG in 10 ml of glycerol, ethanol, distilled water, and 5% bovine serum albumin, then diluted each solution 5- to 10 6 -fold with distilled water. The gauze was dyed using these solutions. A rigid laparoscope observed the fluorescent gauze in a dark room under NIR light, and FI was measured. The gauze treated with a 100-fold dilution of each ICG dyestuff showed the strongest fluorescence. This gauze was then placed in a pig's abdominal cavity and observed under NIR light, demonstrating that the fluorescence could penetrate two or three layers of the mesentery. Our fluorescent gauze, confirmed both ex vivo and in vivo, should be manufactured for clinical use and further validated for its utility. fluorescent gauze gauze indocyanine green near-infrared fluorescence near-infrared imaging Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Gauze is an essential medical material with various applications, and surgical gauze is indispensable to surgeons. It is used not only to wipe blood from surgical fields but also to compress organs and as a marker for surgical manipulation. Surgical gauze is occasionally lost during surgery. Gauze remnants can cause health problems and are occasionally found as retained surgical sponges (Gossypiboma) [ 1 ]. Gawande et al. reported that the incidence of retained sponges and instruments varied from 1/8,801 to 1/18,760 during inpatient operations in non-specialty acute care hospitals [ 2 ]. Retained surgical gauze is a rare and preventable problem that persists despite the use of gauze with radiopaque markers and standardized protocols for gauze counting. The search for lost gauze is time-consuming, especially in laparoscopic surgery, and it involves unnecessary radiation exposure to patients and medical staff. Indocyanine green (ICG) fluorescence-guided surgery is widely performed, and during this procedure camera devices equipped with near-infrared (NIR) light are available in many countries. We considered that a fluorescent gauze dyed with ICG that fluoresces under NIR light would be useful for identifying lost gauze in the body during surgery. During this study, we produced a fluorescent gauze dyed with ICG and evaluated the fluorescence intensity (FI) of the gauze ex vivo and in vivo. Materials and Methods This study was conducted at the Medical Device Innovation Platform, following the Foundation for Kobe International Medical Alliance Animal Experimentation Regulations, and it was approved by the Institutional Animal Care and Use Committee (permission number: K-23-036). All procedures in the animal study were performed in accordance with the institutional ethical standards in compliance with the ARRIVE guidelines ( https://arriveguidelines.org ) and all relevant guidelines and regulations. A pig for this study was provided by the IVTEC Corporation Animal Experimentation Regulations (permission number IVTeC No.23–067). This experimental study was designed in compliance with the 3Rs principles (Replacement, Refinement, and Reduction) and developed in congruence with the best animal welfare conditions. Accordingly, it was initiated ex vivo and performed in a pig model to replicate human characteristics, thereby facilitating its reproducibility and potential transfer. In this study, a 38 kg female pig was used and housed in a group and acclimatized for 1 week in an enriched environment with circadian cycles of light darkness, constant humidity, and temperature conditions. The subject fasted for 24 hours before surgery, had ad libitum access to water, and was sedated (xylazine 2 mg/kg + ketamine 10 mg/kg IM) before the procedure to decrease stress. Anesthesia induction was achieved through isoflurane inhalation before intubation and maintained with rocuronium 0.6 mg/kg along with inhaled sevoflurane 2–5%. Finally, the animals were euthanized using a lethal intravenous dose of potassium chloride before being discarded. Preparation of ICG diluted solutions Indocyanine green was used as the fluorescent agent. Glycerol, ethanol, distilled water, and 5% bovine serum albumin were used as solvents. ICG (25 mg) was dissolved in 10 ml of solvent solution. Each ICG solution was diluted 10- to 10 4 -fold with distilled water to prepare the ICG-diluted solutions. Preparation of fluorescent gauze Each ICG solution was diluted with distilled water from 5- to 10 6 -fold to prepare each dyestuff. Each sterilized gauze (Stellaze 5 × 5 cm; Hakujuji, Japan) was soaked in the dyestuff for a few minutes and dried in a dark room. The gauze was stored under light-shielding conditions. Near-Infrared imaging A laparoscopic camera system (VISERA ELITE II; Olympus, Tokyo, Japan) was used for NIR imaging. The diluted ICG solutions and fluorescent gauze were observed under white and NIR light (magenta and monochrome modes). Ex vivo setting The laparoscope was placed 20 cm from the ICG-diluted solutions on the tube holder and 25 cm from the fluorescent gauze on the table. Undyed gauze was used as a negative control and an ICG reference card (Diagnostic Green GmbH, Germany) was used as a positive control. The objects were observed in a dark room. In vivo setting The strongest fluorescent gauze dyed with each dyestuff was placed in the abdominal cavity of the pig through a laparoscopic trocar. The gauze was covered with mesenteries to check tissue penetration of the fluorescence. Measurement of the fluorescence intensity Using monochrome mode images, the FIs of the ICG-diluted solutions and fluorescent gauze were measured using the Java-based image processing program, ImageJ. In this study, FI was defined as the value indicating brightness per unit pixel. An 8-bit image was expressed in 256 steps from 0 to 255. Six regions of interest (ROI) were set on the fluorescent objects, and the mean FI was measured. Statistical analysis The mean FI data of each subject were compared using the Tukey–Kramer method. Statistical significance was set at p < 0.05. All calculations were performed using JMP software version Pro 17 (SAS Institute, Cary, NC, USA). Results Fluorescence intensity of the ICG diluted solution in ex vivo (Figs. 1 and 2 ) The mean FI values of the ICG-diluted solutions in the glycerol group were 25.4, 51.5, 59.2, 69.1, and 54.3 for the 10-, 10 2 -, 10 3 -, 10 4 -fold diluted, and undiluted solutions, respectively. Similarly, the values were 46.8, 76.0, 80.7, 88.6, and 75.6 in the ethanol group; 3.1, 3.3, 8.3, 13.6, and 7.7 in the water group; and 3.3, 14.2, 28.6, 34.5, and 22.6 in the albumin group. Each 1000-fold diluted ICG solution had the highest FI value. Among the 1000-fold ICG-diluted solutions, the FI was significantly stronger in the ethanol, glycerol, albumin, and water groups. Fluorescence intensity of the fluorescent gauze in ex vivo (Figs. 3 and 4 ) The mean FI values were 15.6, 27.0, 49.3, 24.0, 7.6, 5.6, and 5.2 in the gauze dyed with 5-, 10-, 10 2 -, 10 3 -, 10 4 -, 10 5 -, and 10 6 -fold dyestuffs of glycerol, respectively. Similarly, the values were 7.4, 14.3, 51.4, 50.3, 9.4, 6.6, and 4.8 in the ethanol group, 6.3, 14.1, 41.0, 22.9, 6.2, 5.1, and 3.8 in the water group, 4.8, 13.9, 30.3, 17.6, 4.9, 4.8, and 4.2 in the albumin group. Each fluorescent gauze dyed with 100-fold dyestuff exhibited the strongest FI. Among the fluorescent gauzes dyed with the 100-fold dyestuff, the FIs of those in the ethanol and glycerol groups were significantly stronger than those in the water group, and the FI of those in the water group was significantly stronger than those in the albumin group. The fluorescent gauze in vivo After the fluorescent gauze dyed with 100-fold diluted dyestuff was inserted into the porcine abdominal cavity, each gauze exhibited strong fluorescence under NIR imaging (Supplementary Video). The fluorescence of the gauze dyed with the 100-fold diluted dyestuff in glycerol penetrated up to three layers of the mesentery, whereas that of ethanol, water, and albumin penetrated up to two layers of the mesentery (Supplementary video). Photographs of the gauze dyed with the 100-fold diluted dyestuff of pure ICG solution are shown in Fig. 5 . Discussion We developed a gauze with strong fluorescence emission under NIR imaging, ex vivo and in vivo. This is the first experimental report showing that gauze dyed with ICG dyestuff emits fluorescence and that the FI varies with the concentration of ICG dyestuff, with the gauze fluorescence penetrating several layers of the mesentery. In this study, ICG dissolved in four solvents was used to confirm its fluorescence as a dyestuff before preparing the fluorescence gauze. While a pure ICG diluted solution exhibits an unstable and weak FI due to ICG aggregation, dimethyl sulfoxide, methanol, and ethanol are known to enhance ICG fluorescence, as well as blood plasma [ 3 ]. In this study, the addition of glycerol to ICG enhanced the ICG FI. The fluorescence intensity of ICG does not always correspond to its concentration because of the quenching effect [ 4 ]. This study also demonstrated that cellulose alone, a component of the gauze, enhanced ICG fluorescence. Therefore, it is important to note that no additional enhancers were required to produce the fluorescent gauze. In addition, a high concentration of the ICG-diluted solution did not result in a high FI in the gauze. ICG fluorescence-guided surgery is widely used during various surgeries [ 4 ]. Recently, NIR fluorescent solid materials have been developed [ 5 ], and several fluorescent medical devices have been used in image-guided surgery [ 6 , 7 ]. The developed NIR-coating material can be used in various medical applications [ 8 ]. In a previous study, a fluorescent gauze coated with a Cy-C18 TPB-based coating material soaked in blood was identified using an NIR laparoscopic system. However, no fluorescent gauze is commercially available. To the best of our knowledge, there has been only one case report on the use of a fluorescent gauze with ICG. Kumata et al. reported that ICG-containing gauze was useful in identifying the dissection layer under NIR imaging during laparoscopic intersphincteric resection [ 9 ]. The authors used fluorescent gauze soaked in a liquid prepared by dissolving 25 mg of ICG in 10 ml of water containing sodium arginine. Although this gauze can be easily prepared in a clinical setting, the authors did not consider the concentrations of ICG and arginine required for viscosity enhancement. Moreover, the use of gauze must be approved by an ethics committee because it is off-label for ICG. Thus, fluorescent gauze must be manufactured under the Pharmaceutical Affairs Law. Based on our results, a pure ICG-diluted solution seems to be an optimal dyestuff because glycerol and ethanol are chemical compounds and albumin is a biologically derived product. More importantly, ICG is safe for injection. Fluorescent gauze is useful in various operations, especially in minimally invasive procedures. First, it is expected to reduce the incidence of gauze loss during surgery. When a lost gauze is recognized after gauze counting, fluorescence can be used to locate any material that is behind organs and tissues using NIR imaging before transferring the C-arm fluoroscope for radiation. In addition, fluorescent gauze can be used for ICG fluorescence-guided surgery. Therefore, it may serve as an effective marker for surgical manipulation. For example, surgeons often include gauze in the gap between the mesentery and retroperitoneum as a marker of peritoneal dissection during colorectal surgery. This study has several limitations. First, our gauze is a prototype of a fluorescent gauze. Although the strongest fluorescence was observed in the gauze dyed with a 100-fold dilution of each ICG solution, the optimal concentration of the dye solution remains unknown. Additionally, uneven dyeing may occur on the fluorescent gauze, although a manufacturing system can be used to produce a uniformly dyed gauze. The ICG stain adhered to the tissue because the gauze was only dyed with the ICG solution and dried. Thus, dyeing, refining, bleaching, drying, and sterilization methods should also be considered since FI may be attenuated during each process. Another key factor is the strength of the NIR light of the device, which is strongly related to the FI. Our study evaluated a limited number of fluorescent gauzes using a single laparoscopic NIR imaging device. Therefore, further studies are required. Secondly, the binding of ICG to cellulose may emit fluorescence under NIR light. This process needs to be elucidated by molecular structural analysis. Finally, fluorescent gauze for clinical use should be manufactured according to medical gauze standards, and its safety and usefulness should be validated in various operations. Conclusions We developed a fluorescent gauze using ICG, and strong fluorescence emission was confirmed using laparoscopic NIR imaging, ex vivo and in vivo. This gauze should be manufactured for clinical use and its usefulness should be validated. Abbreviations ICG: Indocyanine green FI: fluorescence intensity NIR: near-infrared Declarations Funding: The authors have no source of funding to declare. Disclosures Takeshi Urade, Shinobu Tsuchida, Kentaro Oji, Yoshiaki Fujiwara, Yasushi Fukuoka, Takahiro Yasuda, and Takumi Fukumoto have no conflicts of interest or financial ties to disclose. Author contributions Study conception and design: Urade, Tsuchida Acquisition of data: Urade, Tsuchida, Oji, Fujiwara, Fukuoka, Yasuda Analysis and interpretation of data: Urade, Tsuchida, Oji Drafting of manuscript: Urade, Tsuchida Critical revision: Fukumoto Data availability All the data obtained and/or analyzed during the current study are available from the corresponding authors on reasonable request. Additional information The authors declare the following competing financial interest(s): S. T. and T.U. have submitted a patent application (PCT International Application) protecting the methodology described in this article. References Bani-Hani KE, Gharaibeh KA, Yaghan RJ (2005) Retained surgical sponges (gossypiboma). Asian J Surg 28:109-115. Gawande AA, Studdert DM, Orav EJ, Brennan TA, Zinner MJ (2003) Risk factors for retained instruments and sponges after surgery. New Eng J Med 348:229-235. Benson RC, Kues HA (1978) Fluorescence properties of indocyanine green as related to angiography. Phys Med Biol 23:159-163. Kusano M, Kokudo N, Toi M, Kaibori M (2016) ICG fluorescence imaging and navigation surgery. Springer, Japan Anayama T, Sato T, Hirohashi K, Miyazaki R, Yamamoto M, Okada H, Orihashi K, et al. (2020) Near-infrared fluorescent solid material for visualizing indwelling devices implanted for medical use. Surg Endosc 34:4206-4213. Namikawa T, Iwabu J, Hashiba M, Munekage M, Uemura S, Yamada T, Kitagawa H, et al. (2020) Novel endoscopic marking clip equipped with resin-conjugated fluorescent indocyanine green during laparoscopic surgery for gastrointestinal cancer. Langenbecks Arch Surg 405:503-508. Ryu S, Ishida K, Okamoto A, Nakashima K, Hara K, Ito R, Nakabayashi Y (2020) Laparoscopic fluorescence navigation for left-sided colon and rectal cancer: Blood flow evaluation, vessel and ureteral navigation, clip marking and trans-anal tube insertion. Surg Oncol 35:434-440. Ashoka AH, Kong SH, Seeliger B, Andreiuk B, Soares RV, Barberio M, Diana M, Klymchenko AS (2020) Near-infrared fluorescent coatings of medical devices for image-guided surgery. Biomat 261:120306. Kumata H, Onishi K, Takayama T, Asami K, Obara N, Sugawara H, Haga I (2022) Efficacy of intraoperative fluorescence imaging using indocyanine green-containing gauze in identifying the appropriate dissection layer in laparoscopic intersphincteric resection: A case report. Clin Case Reports 10:e6356. Additional Declarations No competing interests reported. Supplementary Files Supplementaryvideo.mp4 Cite Share Download PDF Status: Published Journal Publication published 25 Mar, 2025 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 24 Feb, 2025 Reviews received at journal 22 Feb, 2025 Reviewers agreed at journal 08 Feb, 2025 Reviews received at journal 18 Jan, 2025 Reviewers agreed at journal 09 Jan, 2025 Reviewers invited by journal 02 Nov, 2024 Editor assigned by journal 08 Jun, 2024 Editor invited by journal 08 Jun, 2024 Submission checks completed at journal 06 Jun, 2024 First submitted to journal 03 Jun, 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-4519399","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":312923043,"identity":"4065ce6d-9e1c-4e0c-8dd1-5dc2bbb31411","order_by":0,"name":"Takeshi Urade","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3klEQVRIiWNgGAWjYJACCSDi4Zc/fADEliFSS4KFjOQMtgQQm4dYLRU2Bjd4DEAcwloMbh9+eOPjD6Dht3s+v7pRY8HDwH746Aa8Ws6lGVvOSJDgYZxzdpt1zjGgXp60tBt4tZxhMJPmAWphZsjdZpzDBtQiwWNGQAv7N+k/QC1sDDnPjHP+EaWFx0yaAaiFRyKH+XFuGxFaJM/wFFv2pEnwSPAcM2PO7QNaR8gvfGfYN974YVNnb3+8+fHnnG91cvzsh4/h1YIM2CTAJLHKQYD5AymqR8EoGAWjYOQAAP8MQgunNRsRAAAAAElFTkSuQmCC","orcid":"","institution":"Kobe University","correspondingAuthor":true,"prefix":"","firstName":"Takeshi","middleName":"","lastName":"Urade","suffix":""},{"id":312923044,"identity":"afad44bd-ac27-4390-88e6-f4d5562e5ab7","order_by":1,"name":"Shinobu Tsuchida","email":"","orcid":"","institution":"Mitsubishi Kobe Hospital","correspondingAuthor":false,"prefix":"","firstName":"Shinobu","middleName":"","lastName":"Tsuchida","suffix":""},{"id":312923045,"identity":"534f37c7-6b9d-40ef-bbc4-5579e573510c","order_by":2,"name":"Kentaro Oji","email":"","orcid":"","institution":"Kobe University","correspondingAuthor":false,"prefix":"","firstName":"Kentaro","middleName":"","lastName":"Oji","suffix":""},{"id":312923046,"identity":"b3d92c53-a8ea-4fc7-945c-4857861d3f86","order_by":3,"name":"Yoshiaki Fujiwara","email":"","orcid":"","institution":"Kobe University","correspondingAuthor":false,"prefix":"","firstName":"Yoshiaki","middleName":"","lastName":"Fujiwara","suffix":""},{"id":312923047,"identity":"cf9cc01e-b6c0-49af-a5a9-2d2e9ffcac4f","order_by":4,"name":"Yasushi Fukuoka","email":"","orcid":"","institution":"Kobe University","correspondingAuthor":false,"prefix":"","firstName":"Yasushi","middleName":"","lastName":"Fukuoka","suffix":""},{"id":312923048,"identity":"a56fe6e4-4cd2-42c5-bd79-5ff9f910351e","order_by":5,"name":"Takahiro Yasuda","email":"","orcid":"","institution":"Kobe University","correspondingAuthor":false,"prefix":"","firstName":"Takahiro","middleName":"","lastName":"Yasuda","suffix":""},{"id":312923049,"identity":"cbbe1241-ae09-4442-9653-d845f9e40127","order_by":6,"name":"Takumi Fukumoto","email":"","orcid":"","institution":"Kobe University","correspondingAuthor":false,"prefix":"","firstName":"Takumi","middleName":"","lastName":"Fukumoto","suffix":""}],"badges":[],"createdAt":"2024-06-03 05:31:49","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4519399/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4519399/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-025-94944-9","type":"published","date":"2025-03-25T15:57:24+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":59121633,"identity":"e7e8d515-3adb-4052-8226-b33f84632166","added_by":"auto","created_at":"2024-06-26 14:57:16","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":687493,"visible":true,"origin":"","legend":"\u003cp\u003eA photograph of a series of ICG diluted solutions. Twenty-five mg of ICG was dissolved in 10 ml of each solvent (glycerol, ethanol, distilled water, and 5% bovine serum albumin). Each ICG solution was diluted with distilled water (from left to right: undiluted, x10, x10\u003csup\u003e2\u003c/sup\u003e, x10\u003csup\u003e3\u003c/sup\u003e, and x10\u003csup\u003e4\u003c/sup\u003e diluted) under white light and NIR light. A, Glycerol. B, Ethanol. C, Distilled water, D, 5% bovine serum albumin. * means p-value \u0026lt; 0.05.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/5bea2cf10277bf6accb61d68.png"},{"id":59120802,"identity":"d0fd5294-077f-454e-a6d2-f1f7b170e2a0","added_by":"auto","created_at":"2024-06-26 14:49:16","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":34661,"visible":true,"origin":"","legend":"\u003cp\u003eAverage fluorescence intensity of the ICG diluted solutions. * means p-value \u0026lt; 0.05.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/1cc6a6c2d93373caedaa5a5c.png"},{"id":59120803,"identity":"c359ffc7-ffd7-4253-8572-636f5ec7d8e7","added_by":"auto","created_at":"2024-06-26 14:49:16","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1387858,"visible":true,"origin":"","legend":"\u003cp\u003eA series of fluorescent gauze dyed with each ICG diluted solution. Twenty-five mg of ICG was dissolved with 10 ml of each solvent. Each ICG solution was diluted with distilled water to produce each dyestuff. (from top to bottom: glycerol, ethanol, distilled water, and 5% bovine serum albumin; from left to right: x5, x10, x10\u003csup\u003e2\u003c/sup\u003e, x10\u003csup\u003e3\u003c/sup\u003e, x10\u003csup\u003e4\u003c/sup\u003e, x10\u003csup\u003e5\u003c/sup\u003e, and x10\u003csup\u003e6\u003c/sup\u003e diluted). A, white light. B, NIR light for magenta mode. C, NIR light for monochrome mode.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/ef1dd2268d6ced88caa91eb4.png"},{"id":59120800,"identity":"95a2266e-a90a-4d64-8564-ecd3d1f758c5","added_by":"auto","created_at":"2024-06-26 14:49:16","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":31318,"visible":true,"origin":"","legend":"\u003cp\u003eAverage fluorescence intensity of the fluorescent gauze. * means p-value \u0026lt; 0.05.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/877eb9501bd4185776677556.png"},{"id":59120801,"identity":"7f77e591-1a84-4ba1-a46d-0835e42787bd","added_by":"auto","created_at":"2024-06-26 14:49:16","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":1711594,"visible":true,"origin":"","legend":"\u003cp\u003eA fluorescent gauze dyed with a 100-fold pure ICG diluted solution in the abdominal cavity. A, white light. B, NIR light for the magenta mode. C, NIR light for the monochrome mode. D, under three mesenteries. E, under two mesenteries. F, under a mesentery.\u003c/p\u003e","description":"","filename":"Figure5.png","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/783b5213871a6e882251cf17.png"},{"id":79604872,"identity":"55d9dfb0-1535-4324-a6e9-e36f9b4b0741","added_by":"auto","created_at":"2025-03-31 16:08:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5924550,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/923ed061-a24d-48cc-a67b-ceda0e8dafbd.pdf"},{"id":59120805,"identity":"c9b7d622-94b0-4fe5-942f-1942809a4e4f","added_by":"auto","created_at":"2024-06-26 14:49:20","extension":"mp4","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":264950083,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementaryvideo.mp4","url":"https://assets-eu.researchsquare.com/files/rs-4519399/v1/6b5ffaa1869f6376d56ad9e1.mp4"}],"financialInterests":"No competing interests reported.","formattedTitle":"Development of a novel fluorescent gauze using indocyanine green","fulltext":[{"header":"Introduction","content":"\u003cp\u003eGauze is an essential medical material with various applications, and surgical gauze is indispensable to surgeons. It is used not only to wipe blood from surgical fields but also to compress organs and as a marker for surgical manipulation. Surgical gauze is occasionally lost during surgery. Gauze remnants can cause health problems and are occasionally found as retained surgical sponges (Gossypiboma) [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Gawande et al. reported that the incidence of retained sponges and instruments varied from 1/8,801 to 1/18,760 during inpatient operations in non-specialty acute care hospitals [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Retained surgical gauze is a rare and preventable problem that persists despite the use of gauze with radiopaque markers and standardized protocols for gauze counting. The search for lost gauze is time-consuming, especially in laparoscopic surgery, and it involves unnecessary radiation exposure to patients and medical staff.\u003c/p\u003e \u003cp\u003eIndocyanine green (ICG) fluorescence-guided surgery is widely performed, and during this procedure camera devices equipped with near-infrared (NIR) light are available in many countries. We considered that a fluorescent gauze dyed with ICG that fluoresces under NIR light would be useful for identifying lost gauze in the body during surgery. During this study, we produced a fluorescent gauze dyed with ICG and evaluated the fluorescence intensity (FI) of the gauze ex vivo and in vivo.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eThis study was conducted at the Medical Device Innovation Platform, following the Foundation for Kobe International Medical Alliance Animal Experimentation Regulations, and it was approved by the Institutional Animal Care and Use Committee (permission number: K-23-036). All procedures in the animal study were performed in accordance with the institutional ethical standards in compliance with the ARRIVE guidelines (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://arriveguidelines.org\u003c/span\u003e\u003cspan address=\"https://arriveguidelines.org\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) and all relevant guidelines and regulations. A pig for this study was provided by the IVTEC Corporation Animal Experimentation Regulations (permission number IVTeC No.23\u0026ndash;067). This experimental study was designed in compliance with the 3Rs principles (Replacement, Refinement, and Reduction) and developed in congruence with the best animal welfare conditions. Accordingly, it was initiated ex vivo and performed in a pig model to replicate human characteristics, thereby facilitating its reproducibility and potential transfer. In this study, a 38 kg female pig was used and housed in a group and acclimatized for 1 week in an enriched environment with circadian cycles of light darkness, constant humidity, and temperature conditions. The subject fasted for 24 hours before surgery, had ad libitum access to water, and was sedated (xylazine 2 mg/kg\u0026thinsp;+\u0026thinsp;ketamine 10 mg/kg IM) before the procedure to decrease stress. Anesthesia induction was achieved through isoflurane inhalation before intubation and maintained with rocuronium 0.6 mg/kg along with inhaled sevoflurane 2\u0026ndash;5%. Finally, the animals were euthanized using a lethal intravenous dose of potassium chloride before being discarded.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePreparation of ICG diluted solutions\u003c/h2\u003e \u003cp\u003eIndocyanine green was used as the fluorescent agent. Glycerol, ethanol, distilled water, and 5% bovine serum albumin were used as solvents. ICG (25 mg) was dissolved in 10 ml of solvent solution. Each ICG solution was diluted 10- to 10\u003csup\u003e4\u003c/sup\u003e-fold with distilled water to prepare the ICG-diluted solutions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003ePreparation of fluorescent gauze\u003c/h2\u003e \u003cp\u003eEach ICG solution was diluted with distilled water from 5- to 10\u003csup\u003e6\u003c/sup\u003e-fold to prepare each dyestuff. Each sterilized gauze (Stellaze 5 \u0026times; 5 cm; Hakujuji, Japan) was soaked in the dyestuff for a few minutes and dried in a dark room. The gauze was stored under light-shielding conditions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eNear-Infrared imaging\u003c/h2\u003e \u003cp\u003eA laparoscopic camera system (VISERA ELITE II; Olympus, Tokyo, Japan) was used for NIR imaging. The diluted ICG solutions and fluorescent gauze were observed under white and NIR light (magenta and monochrome modes).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eEx vivo setting\u003c/h2\u003e \u003cp\u003eThe laparoscope was placed 20 cm from the ICG-diluted solutions on the tube holder and 25 cm from the fluorescent gauze on the table. Undyed gauze was used as a negative control and an ICG reference card (Diagnostic Green GmbH, Germany) was used as a positive control. The objects were observed in a dark room.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eIn vivo setting\u003c/h3\u003e\n\u003cp\u003eThe strongest fluorescent gauze dyed with each dyestuff was placed in the abdominal cavity of the pig through a laparoscopic trocar. The gauze was covered with mesenteries to check tissue penetration of the fluorescence.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eMeasurement of the fluorescence intensity\u003c/h2\u003e \u003cp\u003eUsing monochrome mode images, the FIs of the ICG-diluted solutions and fluorescent gauze were measured using the Java-based image processing program, ImageJ. In this study, FI was defined as the value indicating brightness per unit pixel. An 8-bit image was expressed in 256 steps from 0 to 255. Six regions of interest (ROI) were set on the fluorescent objects, and the mean FI was measured.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eThe mean FI data of each subject were compared using the Tukey\u0026ndash;Kramer method. Statistical significance was set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. All calculations were performed using JMP software version Pro 17 (SAS Institute, Cary, NC, USA).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eFluorescence intensity of the ICG diluted solution in ex vivo (Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe mean FI values of the ICG-diluted solutions in the glycerol group were 25.4, 51.5, 59.2, 69.1, and 54.3 for the 10-, 10\u003csup\u003e2\u003c/sup\u003e-, 10\u003csup\u003e3\u003c/sup\u003e-, 10\u003csup\u003e4\u003c/sup\u003e-fold diluted, and undiluted solutions, respectively. Similarly, the values were 46.8, 76.0, 80.7, 88.6, and 75.6 in the ethanol group; 3.1, 3.3, 8.3, 13.6, and 7.7 in the water group; and 3.3, 14.2, 28.6, 34.5, and 22.6 in the albumin group. Each 1000-fold diluted ICG solution had the highest FI value. Among the 1000-fold ICG-diluted solutions, the FI was significantly stronger in the ethanol, glycerol, albumin, and water groups.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eFluorescence intensity of the fluorescent gauze in ex vivo (Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e)\u003c/h2\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe mean FI values were 15.6, 27.0, 49.3, 24.0, 7.6, 5.6, and 5.2 in the gauze dyed with 5-, 10-, 10\u003csup\u003e2\u003c/sup\u003e-, 10\u003csup\u003e3\u003c/sup\u003e-, 10\u003csup\u003e4\u003c/sup\u003e-, 10\u003csup\u003e5\u003c/sup\u003e-, and 10\u003csup\u003e6\u003c/sup\u003e-fold dyestuffs of glycerol, respectively. Similarly, the values were 7.4, 14.3, 51.4, 50.3, 9.4, 6.6, and 4.8 in the ethanol group, 6.3, 14.1, 41.0, 22.9, 6.2, 5.1, and 3.8 in the water group, 4.8, 13.9, 30.3, 17.6, 4.9, 4.8, and 4.2 in the albumin group. Each fluorescent gauze dyed with 100-fold dyestuff exhibited the strongest FI. Among the fluorescent gauzes dyed with the 100-fold dyestuff, the FIs of those in the ethanol and glycerol groups were significantly stronger than those in the water group, and the FI of those in the water group was significantly stronger than those in the albumin group.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eThe fluorescent gauze in vivo\u003c/h2\u003e \u003cp\u003eAfter the fluorescent gauze dyed with 100-fold diluted dyestuff was inserted into the porcine abdominal cavity, each gauze exhibited strong fluorescence under NIR imaging (Supplementary Video). The fluorescence of the gauze dyed with the 100-fold diluted dyestuff in glycerol penetrated up to three layers of the mesentery, whereas that of ethanol, water, and albumin penetrated up to two layers of the mesentery (Supplementary video). Photographs of the gauze dyed with the 100-fold diluted dyestuff of pure ICG solution are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe developed a gauze with strong fluorescence emission under NIR imaging, ex vivo and in vivo. This is the first experimental report showing that gauze dyed with ICG dyestuff emits fluorescence and that the FI varies with the concentration of ICG dyestuff, with the gauze fluorescence penetrating several layers of the mesentery.\u003c/p\u003e \u003cp\u003eIn this study, ICG dissolved in four solvents was used to confirm its fluorescence as a dyestuff before preparing the fluorescence gauze. While a pure ICG diluted solution exhibits an unstable and weak FI due to ICG aggregation, dimethyl sulfoxide, methanol, and ethanol are known to enhance ICG fluorescence, as well as blood plasma [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. In this study, the addition of glycerol to ICG enhanced the ICG FI. The fluorescence intensity of ICG does not always correspond to its concentration because of the quenching effect [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. This study also demonstrated that cellulose alone, a component of the gauze, enhanced ICG fluorescence. Therefore, it is important to note that no additional enhancers were required to produce the fluorescent gauze. In addition, a high concentration of the ICG-diluted solution did not result in a high FI in the gauze.\u003c/p\u003e \u003cp\u003eICG fluorescence-guided surgery is widely used during various surgeries [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Recently, NIR fluorescent solid materials have been developed [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], and several fluorescent medical devices have been used in image-guided surgery [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The developed NIR-coating material can be used in various medical applications [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. In a previous study, a fluorescent gauze coated with a Cy-C18 TPB-based coating material soaked in blood was identified using an NIR laparoscopic system. However, no fluorescent gauze is commercially available. To the best of our knowledge, there has been only one case report on the use of a fluorescent gauze with ICG. Kumata et al. reported that ICG-containing gauze was useful in identifying the dissection layer under NIR imaging during laparoscopic intersphincteric resection [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The authors used fluorescent gauze soaked in a liquid prepared by dissolving 25 mg of ICG in 10 ml of water containing sodium arginine. Although this gauze can be easily prepared in a clinical setting, the authors did not consider the concentrations of ICG and arginine required for viscosity enhancement. Moreover, the use of gauze must be approved by an ethics committee because it is off-label for ICG. Thus, fluorescent gauze must be manufactured under the Pharmaceutical Affairs Law. Based on our results, a pure ICG-diluted solution seems to be an optimal dyestuff because glycerol and ethanol are chemical compounds and albumin is a biologically derived product. More importantly, ICG is safe for injection.\u003c/p\u003e \u003cp\u003eFluorescent gauze is useful in various operations, especially in minimally invasive procedures. First, it is expected to reduce the incidence of gauze loss during surgery. When a lost gauze is recognized after gauze counting, fluorescence can be used to locate any material that is behind organs and tissues using NIR imaging before transferring the C-arm fluoroscope for radiation. In addition, fluorescent gauze can be used for ICG fluorescence-guided surgery. Therefore, it may serve as an effective marker for surgical manipulation. For example, surgeons often include gauze in the gap between the mesentery and retroperitoneum as a marker of peritoneal dissection during colorectal surgery.\u003c/p\u003e \u003cp\u003eThis study has several limitations. First, our gauze is a prototype of a fluorescent gauze. Although the strongest fluorescence was observed in the gauze dyed with a 100-fold dilution of each ICG solution, the optimal concentration of the dye solution remains unknown. Additionally, uneven dyeing may occur on the fluorescent gauze, although a manufacturing system can be used to produce a uniformly dyed gauze. The ICG stain adhered to the tissue because the gauze was only dyed with the ICG solution and dried. Thus, dyeing, refining, bleaching, drying, and sterilization methods should also be considered since FI may be attenuated during each process. Another key factor is the strength of the NIR light of the device, which is strongly related to the FI.\u003c/p\u003e \u003cp\u003eOur study evaluated a limited number of fluorescent gauzes using a single laparoscopic NIR imaging device. Therefore, further studies are required. Secondly, the binding of ICG to cellulose may emit fluorescence under NIR light. This process needs to be elucidated by molecular structural analysis. Finally, fluorescent gauze for clinical use should be manufactured according to medical gauze standards, and its safety and usefulness should be validated in various operations.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eWe developed a fluorescent gauze using ICG, and strong fluorescence emission was confirmed using laparoscopic NIR imaging, ex vivo and in vivo. This gauze should be manufactured for clinical use and its usefulness should be validated.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eICG: Indocyanine green\u003c/p\u003e\n\u003cp\u003eFI: fluorescence intensity\u003c/p\u003e\n\u003cp\u003eNIR: near-infrared\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no source of funding to declare.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eDisclosures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTakeshi Urade,\u0026nbsp;Shinobu Tsuchida, Kentaro Oji,\u0026nbsp;Yoshiaki Fujiwara, Yasushi Fukuoka, Takahiro Yasuda, and Takumi Fukumoto have no conflicts of interest or financial ties to disclose.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAuthor contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStudy conception and design: Urade, Tsuchida\u003c/p\u003e\n\u003cp\u003eAcquisition of data: Urade, Tsuchida, Oji, Fujiwara, Fukuoka, Yasuda\u003c/p\u003e\n\u003cp\u003eAnalysis and interpretation of data: Urade, Tsuchida, Oji\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDrafting of manuscript: Urade, Tsuchida\u003c/p\u003e\n\u003cp\u003eCritical revision: Fukumoto\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll the data obtained and/or analyzed during the current study are available from the corresponding authors on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAdditional information\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare the following competing financial interest(s): S. T. and T.U. have submitted a patent application (PCT International Application) protecting the methodology described in this article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBani-Hani KE, Gharaibeh KA, Yaghan RJ (2005) Retained surgical sponges (gossypiboma). Asian J Surg 28:109-115.\u003c/li\u003e\n\u003cli\u003eGawande AA, Studdert DM, Orav EJ, Brennan TA, Zinner MJ (2003) Risk factors for retained instruments and sponges after surgery. New Eng J Med 348:229-235.\u003c/li\u003e\n\u003cli\u003eBenson RC, Kues HA (1978) Fluorescence properties of indocyanine green as related to angiography. Phys Med Biol 23:159-163.\u003c/li\u003e\n\u003cli\u003eKusano M, Kokudo N, Toi M, Kaibori M (2016) ICG fluorescence imaging and navigation surgery. Springer, Japan\u003c/li\u003e\n\u003cli\u003eAnayama T, Sato T, Hirohashi K, Miyazaki R, Yamamoto M, Okada H, Orihashi K, et al. (2020) Near-infrared fluorescent solid material for visualizing indwelling devices implanted for medical use. Surg Endosc 34:4206-4213.\u003c/li\u003e\n\u003cli\u003eNamikawa T, Iwabu J, Hashiba M, Munekage M, Uemura S, Yamada T, Kitagawa H, et al. (2020) Novel endoscopic marking clip equipped with resin-conjugated fluorescent indocyanine green during laparoscopic surgery for gastrointestinal cancer. Langenbecks Arch Surg 405:503-508.\u003c/li\u003e\n\u003cli\u003eRyu S, Ishida K, Okamoto A, Nakashima K, Hara K, Ito R, Nakabayashi Y (2020) Laparoscopic fluorescence navigation for left-sided colon and rectal cancer: Blood flow evaluation, vessel and ureteral navigation, clip marking and trans-anal tube insertion. Surg Oncol\u003cem\u003e \u003c/em\u003e35:434-440.\u003c/li\u003e\n\u003cli\u003eAshoka AH, Kong SH, Seeliger B, Andreiuk B, Soares RV, Barberio M, Diana M, Klymchenko AS (2020) Near-infrared fluorescent coatings of medical devices for image-guided surgery. Biomat 261:120306.\u003c/li\u003e\n\u003cli\u003eKumata H, Onishi K, Takayama T, Asami K, Obara N, Sugawara H, Haga I (2022) Efficacy of intraoperative fluorescence imaging using indocyanine green-containing gauze in identifying the appropriate dissection layer in laparoscopic intersphincteric resection: A case report. Clin Case Reports 10:e6356.\u003c/li\u003e\n\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":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"fluorescent gauze, gauze, indocyanine green, near-infrared fluorescence, near-infrared imaging","lastPublishedDoi":"10.21203/rs.3.rs-4519399/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4519399/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eGauzes are used in various ways, including wiping blood, compressing organs, and as markers during surgery. However, losing gauze during surgery can lead to pieces being left inside the body, causing time-consuming searches and unnecessary radiation exposure. To address this, we developed a fluorescent gauze using indocyanine green (ICG), which fluoresces under near-infrared (NIR) light. This study aimed to evaluate the fluorescence intensity (FI) of the gauze and confirm its fluorescence in a porcine abdominal cavity. We dissolved 25 mg of ICG in 10 ml of glycerol, ethanol, distilled water, and 5% bovine serum albumin, then diluted each solution 5- to 10\u003csup\u003e6\u003c/sup\u003e-fold with distilled water. The gauze was dyed using these solutions. A rigid laparoscope observed the fluorescent gauze in a dark room under NIR light, and FI was measured. The gauze treated with a 100-fold dilution of each ICG dyestuff showed the strongest fluorescence. This gauze was then placed in a pig's abdominal cavity and observed under NIR light, demonstrating that the fluorescence could penetrate two or three layers of the mesentery. Our fluorescent gauze, confirmed both ex vivo and in vivo, should be manufactured for clinical use and further validated for its utility.\u003c/p\u003e","manuscriptTitle":"Development of a novel fluorescent gauze using indocyanine green","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-26 14:49:11","doi":"10.21203/rs.3.rs-4519399/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-02-24T05:26:56+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-02-23T04:18:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"156819299428631602835045536146073292697","date":"2025-02-08T08:30:30+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-01-18T09:54:41+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"248844452836620392873165138861044298174","date":"2025-01-09T08:04:11+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-02T21:54:36+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-08T15:02:41+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-06-08T12:41:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-06-06T07:34:24+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2024-06-03T05:30:29+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"115a953e-91aa-4b62-b72c-783781aff6d2","owner":[],"postedDate":"June 26th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-03-31T16:00:53+00:00","versionOfRecord":{"articleIdentity":"rs-4519399","link":"https://doi.org/10.1038/s41598-025-94944-9","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2025-03-25 15:57:24","publishedOnDateReadable":"March 25th, 2025"},"versionCreatedAt":"2024-06-26 14:49:11","video":"","vorDoi":"10.1038/s41598-025-94944-9","vorDoiUrl":"https://doi.org/10.1038/s41598-025-94944-9","workflowStages":[]},"version":"v1","identity":"rs-4519399","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4519399","identity":"rs-4519399","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}