Protective Effect of Indocyanine Green Fluorescence Imaging Technology on Parathyroid Glands During Total Thyroidectomy

Accurate identification and evaluation of the parathyroid glands (PGs) intraoperatively is critical to reduce the incidence of postoperative hypoparathyroidism after total thyroidectomy. Near-infrared fluorescence imaging (NIFI), including the autofluorescence (AF) and indocyanine green fluorescence (ICGF) imaging, is a promising technique to protect PGs. This study aimed to assess whether the combined use of AF and ICGF could reduce the incidence of postoperative hypoparathyroidism and improve the identification and evaluation of PGs during total thyroidectomy.

Study Overview

• Status: Recruiting
• Conditions: Indocyanine Green; Total Thyroidectomy; Parathyroid Function Low Adverse Event; Parathyroid Glands--Diseases
• Intervention / Treatment: Device: Indocyanine Green; Device: No indocyanine green

Detailed Description

Postoperative hypoparathyroidism or hypocalcemia is the most frequent complication after total thyroidectomy (TT) . The median incidence of transient and permanent postoperative hypoparathyroidism is 27% (19%-38%) and 1% (0-3%), respectively. Transient hypoparathyroidism can increase the length of hospital stay and the costs of hospitalization for patients. Permanent hypoparathyroidism leads to lifelong medication use, which may severely impair the quality of life of patients. Therefore, identifying the parathyroid glands (PGs) and preserving those with adequate blood perfusion intraoperatively has always been a crucial procedure during thyroidectomy.

Conventional means of identification and assessment of PGs are mainly based on surgeon-dependent identification of their anatomical location and appearance (color, shape, etc.) by the naked eye. However, this visual inspection is often influenced by the experience of the surgeon, intraoperative hemorrhage, ectopic PGs and so on, which makes it difficult to fully protect the PGs.

Currently, there has been an emergence of near-infrared fluorescence imaging (NIFI) that can be applied during thyroid or parathyroid surgery for the evaluation and identification of PGs. This technique mainly exploits the autofluorescence (AF) of PGs and indocyanine green fluorescence (ICGF ) imaging.PGs could exhibit stronger AF than the surrounding tissue under near-infrared light, which can be exploited to accurately identify PGs in real time. Subsequent studies have demonstrated that AF can not only detect PGs intraoperatively in real time and improve the intraoperative identification of PGs but also reduce the incidence of postoperative hypoparathyroidism. However, AF cannot assess the status of PG blood perfusion and consequently is not useful when determining whether PGs need to be autotransplanted.

Indocyanine green (ICG) fluorescence imaging may be a great solution to this problem. ICG is a safe fluorescent dye with fast metabolism and few adverse effects that can quickly combine with plasma proteins after intravenous injection and is widely used in angiography in multiple surgical disciplines. In recent years, several studies have shown that ICGF may be superior in evaluating blood perfusion and predicting the function of PGs in situ, subsequently guiding their autotransplantation. However, ICGF may not be very suitable for the identification of PGs before dissection, as the thyroid gland would also emit intense fluorescence after the injection of ICG, which may lead to difficulties in distinguishing them. Thus, AF and ICGF have their own advantages and disadvantages in the identification and evaluation of PGs, respectively. These two methods can be considered complementary.

In the present study, the investigators used AF in combination with ICGF imaging by one fluorescence imaging system during different steps of the surgical procedure. At the beginning of the operation, AF was used to identify the PGs before any dissection. Then, after the thyroid gland was removed, AF was used again to locate the PGs in situ. Finally, ICGF was applied to evaluate the blood perfusion of the PGs in situ and guide their autotransplantation. The aim of this randomized controlled trial was to assess whether this strategy could reduce the incidence of postoperative hypoparathyroidism and benefit the identification and evaluation of PGs during total thyroidectomy.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Xuan Qiu, MD; Phone Number: 8618354280081; Email: qiuxuan100@163.com
• Study Contact Backup: Name: Ni Wang, MD,PD; Phone Number: 8618705353551; Email: wangni1989@163.com

Study Locations

• China
  • Shandong
    • Yantai, Shandong, China, 264000
      • Recruiting
      • Shandong Linglong Yingcheng Hospital
      • Contact: Xuan Qiu, MD; Phone Number: 8618354280081; Email: qiuxuan100@163.com
      • Contact: Ni Wang, MD; Phone Number: 8618705353551; Email: wangni1989@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Male or female patients, aged 18 years and above
• Scheduled for elective total or hemi thyroidectomy
• Normal liver and renal function
• No known hypersensitivity for iodine or ICG
• Able to understand the nature of the study procedures
• Willing to participate and give written informed consent

Exclusion Criteria:

• Age < 18 years
• Liver or renal insufficiency
• Known ICG, iodine, penicillin or sulfa hypersensitivity
• Pregnancy or breastfeeding
• Not able to understand the nature of the study procedure
• Not willing to participate

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Indocyanine green group; Identification of parathyroid glands (PGs) Near-infrared (NIR) fluorescence visualization of PGs, for only experimental group	Device: Indocyanine Green; ICG is a fluorescent dye which binds tightly to plasma proteins and becomes confined to the vascular system.; Other Names: Near Infrared Fluorescence Imaging
Active Comparator: Traditional surgery group; Conventional means of identification and assessment of PGs are mainly based on surgeon-dependent identification of their anatomical location and appearance (color, shape, etc.) by the naked eye.	Device: No indocyanine green; Conventional means of identification and assessment of PGs are mainly based on surgeon-dependent identification of their anatomical location and appearance (color, shape, etc.) by the naked eye.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Identification of parathyroid glands (PGs) by NIR/ICG camera detected high-contrast	İntravenous injection of ICG dye, to identify PGs under NIR (High-contrast fluorescence seen or not)	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Central lymph node dissetion (CLND)	Number of positive lymph nodes (micrometastases)	1 year

Collaborators and Investigators

• Sponsor: Shandong Linglong Yingcheng Hospital
• Investigators: Principal Investigator: Xuan Qiu, MD, Shandong Linglong Yingcheng Hospital

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2024
• Primary Completion (Estimated): June 1, 2025
• Study Completion (Estimated): June 30, 2025

Study Registration Dates

• First Submitted: February 25, 2024
• First Submitted That Met QC Criteria: February 25, 2024
• First Posted (Actual): March 1, 2024

Study Record Updates

• Last Update Posted (Estimated): March 5, 2024
• Last Update Submitted That Met QC Criteria: March 2, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Endocrine System Diseases; Parathyroid Diseases
• Other Study ID Numbers: sdllycyyqx001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No