Basic Research

Intraoperative Parathyroid Localization with Near-Infrared Fluorescence Imaging Using Indocyanine Green during Total Parathyroidectomy for Secondary Hyperparathyroidism

Ellyce Baldwin Basic Research, ICG Fluorescence, Thyroid/Parathyroid

Intraoperative Parathyroid Localization with Near-Infrared Fluorescence Imaging Using Indocyanine Green during Total Parathyroidectomy for Secondary Hyperparathyroidism

 

The detection of all glands during total parathyroidectomy (TPTX) in secondary hyperparathyroidism (SHPT) patients is often difficult due to their variability in number and location. The objective of this study was to evaluate the feasibility of near-infrared fluorescence (NIRF) imaging using indocyanine green (ICG) for intraoperative parathyroid gland (PTG) localization in SHPT patients. Twenty-nine patients with SHPT were divided into two groups with or without intraoperative NIRF imaging. ICG was administered in patients undergoing intraoperative imaging, and the fluorescence of PTGs was assessed. Clinical and histopathologic variables were analyzed to determine factors associated with ICG uptake. Comparisons between NIRF and preoperative imaging, as well as differences between groups with or without NIRF imaging, were carried out to evaluate the efficacy of this technique. Most PTGs could be clearly identified, including one ectopic gland. The sensitivity of NIRF imaging is 91.1% in contrast to 81.82% for ultrasonography (US), 62.34% for 99mTc-MIBI and 85.71% for computed tomography (CT). In addition, intraoperative NIRF imaging can reduce the operation time and improve the complete resection rate compared with the group not using it. Intraoperative NIRF imaging using ICG during TPTX is technically feasible and reliable for assisting surgeons in detecting and confirming PTGs.

 

Bibliographic information

Cui, Le, et al. “Intraoperative Parathyroid Localization with Near-Infrared Fluorescence Imaging Using Indocyanine Green during Total Parathyroidectomy for Secondary Hyperparathyroidism.” Scientific Reports, vol. 7, no. 1, 2017, doi:10.1038/s41598-017-08347-6.

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Parathyroid gland angiography with indocyanine green fluorescence to predict parathyroid function after thyroid surgery

Ellyce Baldwin Basic Research, ICG Fluorescence, ICG Perfusion, Thyroid/Parathyroid

Parathyroid gland angiography with indocyanine green fluorescence to predict parathyroid function after thyroid surgery

 

Postoperative hypocalcaemia following total thyroidectomy is common, and may have a significant effect on quality of life. Transient hypocalcaemia is frequent and has been described in 15–30 per cent of patients, depending on the technical difficulty of the procedure and expertise of the surgeon. Permanent hypocalcaemia, defined as hypocalcaemia present for more than 6 months after thyroidectomy, has been reported in 1–3 per cent of patients1. Some authors have described rates of up to 10 per cent1, 2, which suggests a possible underestimation of the true prevalence of permanent hypocalcaemia after thyroid surgery.

The main cause of hypocalcaemia after total thyroidectomy is hypoparathyroidism due to intraoperative damage to the parathyroid glands by trauma, inadvertent parathyroid gland removal or devascularization. The extent of damage to the parathyroid glands is difficult to predict during surgery. It has been generally accepted that half of one normal parathyroid gland can produce sufficient parathyroid hormone (PTH)2, 3. To avoid postoperative hypocalcaemia, parathyroid autotransplantation can be performed, although the results have been controversial4, 5.

Accurate prediction of post‐thyroidectomy hypocalcaemia has the potential to influence management strategies and could possibly reduce the incidence of hypoparathyroidism if the precise mechanisms of this condition were to be elucidated. Among the newer techniques2, 6, 7, intraoperative parathyroid gland angiography during thyroidectomy might be used to evaluate parathyroid gland perfusion and function.

Initially used in the detection of macular degeneration8, the technique of angiography using indocyanine green (ICG) has been used to identify sentinel lymph nodes9, to determine the extent of oncological resections10 and to study hepatic function11. Recent studies have also demonstrated its usefulness in evaluating the vascular blood flow of intestinal anastomoses12.

The aim of this pilot study was to evaluate the use of ICG angiography in predicting parathyroid gland function and the absence of postoperative hypoparathyroidism in patients in whom good vascularization of at least one parathyroid gland could be demonstrated by the technique.

Bibliographic information

Fortuny, J. Vidal, et al. “Parathyroid gland angiography with indocyanine green fluorescence to predict parathyroid function after thyroid surgery.” British Journal of Surgery, vol. 103, no. 5, Nov. 2016, pp. 537–543., doi:10.1002/bjs.10101.

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A reappraisal of vascular anatomy of the parathyroid gland based on fluorescence techniques

Ellyce Baldwin Basic Research, Hamamatsu PDE, ICG Fluorescence, ICG Perfusion, Thyroid/Parathyroid

A reappraisal of vascular anatomy of the parathyroid gland based on fluorescence techniques

 

Identification of the parathyroid glands (PGs) during thyroid surgery may prevent their inadvertent surgical removal and prevent postoperative hypoparathyroidism. However, identification of the PGs does not guarantee their function, and their vascular supply needs to be preserved as well. The recent introduction of intraoperative indocyanine green (ICG) fluorescent angiography of the PGs during thyroid surgery allows for the appraisal of the vascular anatomy and evaluation of PG function. The use of this tool could lead to a significant reduction in the rate of postoperative hypoparathyroidism, as it allows surgeons to adapt their surgical technique for the preservation of the PGs. ICG fluorescent angiography is currently the only available real-time tool to assess the vascular blood supply of each individual PG intraoperatively and can thus assist surgeons in their decision-making. Herein, we review the relevant literature.

Bibliographic information

Sadowski, Samira Mercedes, et al. “A reappraisal of vascular anatomy of the parathyroid gland based on fluorescence techniques.” Gland Surgery, vol. 6, no. S1, 2017, doi:10.21037/gs.2017.07.10.

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Role of Indocyanine Green in Fluorescence Imaging with Near-Infrared Light to Identify Sentinel Lymph Nodes, Lymphatic Vessels and Pathways Prior to Surgery – A Critical Evaluation of Options

Ellyce Baldwin Basic Research, Hamamatsu PDE, ICG Fluorescence, Sentinel Lymph Biopsy

Role of Indocyanine Green in Fluorescence Imaging with Near-Infrared Light to Identify Sentinel Lymph Nodes, Lymphatic Vessels and Pathways Prior to Surgery – A Critical Evaluation of Options

 

Modern surgical strategies aim to reduce trauma by using functional imaging to improve surgical outcomes. This reviews considers and evaluates the importance of the fluorescent dye indocyanine green (ICG) to visualize lymph nodes, lymphatic pathways and vessels and tissue borders in an interdisciplinary setting. The work is based on a selective search of the literature in PubMed, Scopus, and Google Scholar and the authorsʼ own clinical experience. Because of its simple, radiation-free and uncomplicated application, ICG has become an important clinical indicator in recent years. In oncologic surgery ICG is used extensively to identify sentinel lymph nodes with promising results. In some studies, the detection rates with ICG have been better than the rates obtained with established procedures. When ICG is used for visualization and the quantification of tissue perfusion, it can lead to fewer cases of anastomotic insufficiency or transplant necrosis. The use of ICG for the imaging of organ borders, flap plasty borders and postoperative vascularization has also been scientifically evaluated. Combining the easily applied ICG dye with technical options for intraoperative and interventional visualization has the potential to create new functional imaging procedures which, in future, could expand or even replace existing established surgical techniques, particularly the techniques used for sentinel lymph node and anastomosis imaging.

Using ICG in medicine is simple, radiation-free and safe, and ICG has been shown to be an excellent marker after both interstitial and intravascular administration. The detection rates of ICG-dyed sentinel lymph nodes are at least as good as those reported for established techniques and sometimes even superior. Moreover, using ICG to detect sentinel lymph nodes is less expensive and logistically simpler than protocols which use technetium colloid ( 99mTc) the day before surgery, when it is administered by nuclear medicine specialists in accordance with radiation protection regulations 19 ,  20 .

 

Bibliographic information

Hackethal, Andreas, et al. “Role of Indocyanine Green in Fluorescence Imaging with Near-Infrared Light to Identify Sentinel Lymph Nodes, Lymphatic Vessels and Pathways Prior to Surgery – A Critical Evaluation of Options.” Geburtshilfe und Frauenheilkunde, vol. 78, no. 01, 2018, pp. 54–62., doi:10.1055/s-0043-123937.

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Use of Indocyanine Green for Sentinel Lymph Node Biopsy: Case Series and Methods Comparison

Ellyce Baldwin Basic Research, Hamamatsu PDE, ICG Fluorescence, Sentinel Lymph Biopsy

Use of Indocyanine Green for Sentinel Lymph Node Biopsy: Case Series and Methods Comparison

Sentinel lymph node biopsy is indicated for patients with biopsy-proven thickness melanoma greater than 1.0 mm. Use of lymphoscintigraphy along with vital blue dyes is the gold standard for identifying sentinel lymph nodes intraoperatively. Indocyanine green (ICG) has recently been used as a method of identifying sentinel lymph nodes. We herein describe a case series of patients who have successfully undergone ICG-assisted sentinel lymph node biopsy for melanoma. We compare 2 imaging systems that are used for ICG-assisted sentinel lymph node biopsy.

Bibliographic information

Mcgregor, Andrew, et al. “Use of Indocyanine Green for Sentinel Lymph Node Biopsy.” Plastic and Reconstructive Surgery – Global Open, vol. 5, no. 11, 2017, doi:10.1097/gox.0000000000001566.

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The Diagnostic and Intraoperative Use of NIR ICG in Perforator Flap Procedures: An Animal Study (2009)

Eric Sturgis Anastomosis, Basic Research, Free Flap Perfusion, Free Flaps, General and Transplant Surgery, Hamamatsu PDE, ICG Fluorescence, ICG Perfusion, Microsurgery, Plastic Surgery, Reconstructive Surgery

Image-Guided Perforator Flap Design Using Invisible Near-Infrared Light and Validation with X-Ray Angiography 

In this study, 22 pigs were injected with a bolus of indocyanine green (ICG) through a central venous line and observed with a near infrared (NIR) camera to identify dominant perforator flaps from the deep superior epigastric artery (DSEA). After the flap was identified and cut, it was given another ICG injection to confirm perfusion. In 8 of 22 of the pigs NIR ICG was confirmed with x-ray angiography. Researchers made a direct correlation between the results of the NIR ICG and x-ray angiography. This 2009 animal study “validated the clinical relevance of ICG fluorescence to tissue perfusion… the use of NIR wavelengths for fluorescence emission minimizes tissue autofluorescence and photo scatter, resulting in relatively high sensitivity” (Matsui et al 4).

Bibliographic information

Matsui, A., Lee, B. T., & Frangioni, J. V. (2009). Image-guided perforator flap design using invisible near-infrared light and validation with x-ray angiography. Annals of Plastic Surgery63(3), 327-330. Retrieved from www.ncbi.nlm.nih.gov/pmc/articles/PMC2756078

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