Since its introduction, the indocyanine green (ICG) has been used in various medical specialties. In injected interstitially, it can allow visualizing in real-time subcutaneous lymphatic flow. ICG lymphangiography may result a useful tool for surgeons dealing with lymphedema. Thanks to its proven safety, low costs, low invasiveness and suitability for lymphatic channel assessment, ICG lymphangiography may be used to assess lymphedema severity and enable surgeons to preoperatively stage and select patients who are most suitable for lymphovenous bypass.
ICG lymphangiography has already been tested in sentinel lymph node biopsy (SLNB) in breast cancer treatment. Despite encouraging preliminary results that showed potential advantages over traditional methods, to date there is no consensus on how ICG could complement or replace other validated methods of SLN mapping.
ICG technology has shown more potential in breast cancer surgery. ICG angiography can locate the poorly perfused areas of mastectomy flaps intra-operatively and so help the surgeon to remove them and avoid necrosis complication. Also, in autologous breast reconstruction, the flap perfusion can be assessed using ICG angiography. This check on tissue reliability allows an intraoperative immediate revision, thereby avoiding the patient potential post-operative take-back to surgery for revision. Despite these potential advantages have already been published, there is still no consensus nor validated protocol for ICG angiography use in breast surgery.
The aim of our study is to investigate if the ICG lymphangiography method can be considered equivalent or superior to standard lymphoscintigraphy in lymphedema surgery and in sentinel node detection with traditional radioisotope. Moreover, we would evaluate the role of ICG angiography in assessing mastectomy skin flaps perfusion and flap perfusion in autologous breast reconstruction surgeries.
Since its introduction in healthcare field, ICG has been used in various medical specialities, as in assessing liver function, cardiac output or free flap perfusion in microsurgery. In 2005 Kitai et al., first introduced ICG for fluorescence visualization of lymphatic channels. Indeed, ICG is a low molecular weight organic molecule that completely bounds to plasma proteins. As it fluoresces in the near- infrared wavelength, it can allow to visualize in real-time subcutaneous lymphatic flow. Given this property, ICG lymphangiography may result a useful tool for surgeons dealing with lymphedema. Chronic lymphedema affects 250 million people worldwide, and it is considered an incurable condition in many countries. Lymphoscintigraphy is considered the gold standard to assess lymphatic flow and provide quantitative evaluation of the lymphatic function. Thanks to ICG¿s proven safety, low costs, low invasiveness and suitability for pre, intra, and post-operative lymphatic channel assessment, ICG lymphangiography may be used to assess lymphedema functional severity and enable surgeons to preoperatively stage and select patients who are most suitable for lymphovenous bypass. It may also be used to identify functioning lymphatic vessels and optimal anatomical locations to perform lymphovenous bypass. Finally, this technique may be used as a tool to objectively assess changes in lymphedema status in patients following lymphedema surgery. In particular, we aim to assess ICG lymphangiography reliability and applicability in early to medium lymphedema stages microsurgical treatment with lymphaticovenular anastomoses.
Following this line of reasoning, ICG lymphangiography has already been introduced in the sentinel lymph node biopsy (SLNB) in breast cancer treatment. Despite encouraging preliminary results that showed potential benefits of ICG over traditional SLN identification methods, to date there is no consensus on the best protocol for ICG clinical use in SLNB and how it can complement or replace other traditional methods of SLN mapping. A prospective study would help to shed light over this innovative, safe and FDA approved surgical technology.
As ICG can be injected intravenously too, ICG angiography found significant applications in breast surgery too, besides SLNB. (ICG) angiography with a photodynamic eye (PDE) may help surgeons to achieve uneventful and successful breast reconstruction. Indeed, adequate viability of the tissues left and/or transposed, is of utmost importance for a successful outcome, while mastectomy skin flap ischaemia represents a common occurrence. ICG angiography has been shown to be beneficial in breast reconstruction. It can locate the poorly perfused areas of mastectomy flaps intra-operatively and so help the surgeon to remove them and avoid necrosis complication. Also, in autologous breast reconstruction, the flap perfusion can be assessed using ICG angiography. This check on tissue reliability allows an intraoperative immediate revision, thereby avoiding the patient potential post-operative take-back to surgery for revision. Despite these potential advantages have already been published, there is still no consensus nor validated protocol for ICG angiography use in breast surgery. A prospective study may evaluate how ICG angiography can predict breast reconstruction outcomes thanks to intraoperative assessment of mastectomy flaps or transposed flaps perfusion.