Introduction: Lymphoscintigraphy is the gold standard for imaging in the diagnosis of peripheral lymphedema. However, there are no clear guidelines to standardize usage across centers, and as such, large variability exists. The aim of this perspectives paper is to draw upon the knowledge and extensive experience of lymphoscintigraphy here in Genoa, Italy, from our center of excellence in the assessment and treatment of lymphatic disorders for over 30 years to provide general guidelines for nuclear medicine specialists.
Method: The authors describe the technical characteristics of lymphoscintigraphy in patients with limb swelling. Radioactive tracers, dosage, administration sites, and the rationale for a two-compartment protocol with the inclusion of subfascial lymphatic vessels are all given in detail.
Results: Examples of lymphoscintigraphic investigations with various subgroups of patients are discussed. The concept of a transport index (TI) for semi-quantitative analysis of normal/pathological lymphatic flow is introduced. Different concepts of injection techniques are outlined.
Discussion: It is past time that lymphoscintigraphy in the diagnosis of lymphatic disorders becomes standardized. This represents our first attempt to outline a clear protocol and delineate the relevant points for lymphoscintigraphy in this patient population.
Keywords: Epifascial and subfascial lymphatic vessels; Limb swelling; Lymphoscintigraphy; Semi-quantitative transport index.
Conflict of interest statement
Giuseppe. Villa, Corrado C Campisi, Melissa Ryan, Francesco Boccardo, Pietro di Summa, Marco Frascio, Gianmario Sambuceti, and Corradino Campisi declare that they have no conflict of interest. There is no source of funding.All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.The institutional board of our Institution reviewed the study and approved it as a retrospective study, waiving the need for formal consent. Although no formal consent was required, patients gave their written consent to use their anonymous data.
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