{
    "abstract": "Methods for the non-invasive quantification of changes in bladder wall thickness as potential predictors of radiation cystitis in pre-clinical research would be desirable. The use of ultrasound for this aim seems promising, but is still relatively unexplored. A method using ultrasound for bladder wall thickness quantification in rats was developed and applied to measure early radiation-induced bladder wall thickness changes.\nTwo groups (n\u2009=\u20099 each) of female Fischer rats were treated with a single radiation dose of 25-30 and 35-40\u00a0Gy respectively, using an image-guided micro-irradiator; six untreated rats were monitored as a control group. Empty, half-filled and fully-filled bladder volumes were determined for four non-irradiated rats by measuring axes from ultrasound 3D-images and applying the ellipsoid formula. Mean bladder wall thickness was estimated for both ventral and dorsal bladder sides through the measurement of the bladder wall area along a segment of 4\u00a0mm in the central sagittal scan, in order to minimize operator-dependence on the measurement position. Ultrasound acquisitions of all fully-filled rat bladders were also acquired immediately before, and 4 and 28\u00a0days after irradiation. Mean bladder wall thickness normalized to the baseline value and corrected for filling were then used to evaluate acute bladder wall thickening and to quantify the dose-effect.\nThe relationship between mean bladder wall thickness and volume in unirradiated rats showed that for a bladder volume\u2009>\u20091.5\u00a0mL the bladder wall thickness is almost constant and equal to 0.30\u00a0mm with variations within\u2009\u00b1\u200915%. The average ratios between post and pre irradiation showed a dose-effect relationship. Bladder wall thickening was observed for the 25-30\u00a0Gy and 35-40\u00a0Gy groups in 2/9 (22%) and 5/9 (56%) cases at day 4 and in 4/9 (44%) and 8/9 (89%) cases at day 28, respectively. The two groups showed significantly different bladder wall thickness both relative to the control group (p\u2009<\u20090.0001) and between them (p\u2009=\u20090.022). The bladder wall thickness increment was on average 1.32\u2009\u00b1\u20090.41, and was 1.30\u2009\u00b1\u20090.21 after 25-30\u00a0Gy and 1.47\u2009\u00b1\u20090.29 and 1.90\u2009\u00b1\u20090.83 after 35-40\u00a0Gy at days 4 and 28 respectively.\nThe feasibility of using ultrasound on a preclinical rat model to detect bladder wall thickness changes after bladder irradiation was demonstrated, and a clear dose-effect relationship was quantified. Although preliminary, these results are promising in addressing the potential role of this non-invasive approach in quantifying radiation cystitis.",
    "authors": [
        {
            "affiliation": "Experimental Imaging Centre, IRCCS San Raffaele Scientific Institute, Via Olgettina, 60, 20132, Milan, Italy. spinelli.antonello@hsr.it.",
            "firstname": "Antonello E",
            "initials": "AE",
            "lastname": "Spinelli"
        },
        {
            "affiliation": "Medical Physics, IRCCS San Raffaele Scientific Institute, Milan, Italy.\nFondazione Centro San Raffaele, Milan, Italy.",
            "firstname": "Andrea",
            "initials": "A",
            "lastname": "Bresolin"
        },
        {
            "affiliation": "Urological Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy.",
            "firstname": "Stefania",
            "initials": "S",
            "lastname": "Zuppone"
        },
        {
            "affiliation": "Experimental Imaging Centre, IRCCS San Raffaele Scientific Institute, Via Olgettina, 60, 20132, Milan, Italy.",
            "firstname": "Laura",
            "initials": "L",
            "lastname": "Perani"
        },
        {
            "affiliation": "Urological Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy.",
            "firstname": "Giuseppe",
            "initials": "G",
            "lastname": "Fallara"
        },
        {
            "affiliation": "Radiation Oncology, IRCCS San Raffaele Scientific Institute, Milan, Italy.\nUniversity Vita-Salute San Raffaele, Milan, Italy.",
            "firstname": "Nadia",
            "initials": "N",
            "lastname": "Di Muzio"
        },
        {
            "affiliation": "Urological Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy.\nUniversity Vita-Salute San Raffaele, Milan, Italy.",
            "firstname": "Riccardo",
            "initials": "R",
            "lastname": "Vago"
        },
        {
            "affiliation": "Medical Physics, IRCCS San Raffaele Scientific Institute, Milan, Italy.",
            "firstname": "Claudio",
            "initials": "C",
            "lastname": "Fiorino"
        },
        {
            "affiliation": "Radiation Oncology, IRCCS San Raffaele Scientific Institute, Milan, Italy.",
            "firstname": "Cesare",
            "initials": "C",
            "lastname": "Cozzarini"
        }
    ],
    "conclusions": null,
    "copyrights": null,
    "doi": "10.1186/s13014-020-01684-3\n10.1016/j.urology.2015.11.001\n10.2307/3579834\n10.1080/09553000310001632921\n10.1053/apmr.2002.33985\n10.1142/S2339547816400082\n10.1118/1.3523624\n10.1118/1.3668060\n10.1016/0167-8140(89)90085-6\n10.1016/j.adro.2016.07.004\n10.1007/BF00300073\n10.1080/09553000500147600\n10.1016/j.juro.2008.01.118\n10.1016/j.tcmj.2011.03.005\n10.1038/nmeth.2089\n10.1016/j.radonc.2013.10.003\n10.1016/S0929-6441(10)60015-X\n10.1016/j.icrp.2012.06.009\n10.1002/nau.21223\n10.1016/j.juro.2011.02.047\n10.1007/s00261-009-9540-9\n10.3892/etm.2014.1594",
    "journal": "Radiation oncology (London, England)",
    "keywords": [
        "Animal model",
        "Bladder wall thickness",
        "Radiation cystitis",
        "Radiotherapy",
        "Ultrasound imaging"
    ],
    "methods": null,
    "publication_date": "2020-10-19",
    "pubmed_id": "33069240\n26571081\n10190499\n14761851\n16516041\n12161841\n21361183\n22225275\n2798940\n25839382\n28217761\n8171759\n3521706\n16076754\n8911391\n18423703\n16986025\n22930834\n24183860\n22925378\n22038779\n21511281\n19458995\n24940439",
    "results": "The relationship between mean bladder wall thickness and volume in unirradiated rats showed that for a bladder volume\u2009>\u20091.5\u00a0mL the bladder wall thickness is almost constant and equal to 0.30\u00a0mm with variations within\u2009\u00b1\u200915%. The average ratios between post and pre irradiation showed a dose-effect relationship. Bladder wall thickening was observed for the 25-30\u00a0Gy and 35-40\u00a0Gy groups in 2/9 (22%) and 5/9 (56%) cases at day 4 and in 4/9 (44%) and 8/9 (89%) cases at day 28, respectively. The two groups showed significantly different bladder wall thickness both relative to the control group (p\u2009<\u20090.0001) and between them (p\u2009=\u20090.022). The bladder wall thickness increment was on average 1.32\u2009\u00b1\u20090.41, and was 1.30\u2009\u00b1\u20090.21 after 25-30\u00a0Gy and 1.47\u2009\u00b1\u20090.29 and 1.90\u2009\u00b1\u20090.83 after 35-40\u00a0Gy at days 4 and 28 respectively.",
    "title": "A non-invasive ultrasound imaging method to measure acute radiation-induced bladder wall thickening in rats.",
    "xml": "<Element 'PubmedArticle' at 0x788505ec97b0>"
}