NIRF for Parathyroid Visualization: a Pilot Study

Thyroid Disease Clinical Trial

Official title:

The Use of Near-Infrared Fluorescence Imaging in Parathyroid Visualization During Thyroid Surgery: a Pilot Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03012438
• Other study ID #: NL57409.068.16
• Status: Completed
• Phase: N/A
• First received: January 3, 2017
• Last updated: March 13, 2018
• Start date: March 23, 2017
• Est. completion date: March 12, 2018

Study information

• Verified date: April 2017
• Source: Maastricht University Medical Center
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

During surgery in which the thyroid is removed (thyroidectomy), the identification of parathyroid glands, that should be saved, can be challenging. Therefore, there is need for accurate intraoperative guidance. Earlier animal studies show that the parathyroid glands can be identified by the use of the Near Infrared Fluorescent dye Indocyanine green (ICG).

Our hypothesis is therefore, that the use of ICG-based fluorescence imaging during thyroid surgery will provide real-time intraoperative visualization of the parathyroid glands.

This prospective observational feasibility study aims to evaluate the feasibility of the use of ICG in identifying the parathyroid glands during thyroid surgery. 30 patients (age >18 years) who are already regularly scheduled for thyroid surgery; i.e. patients undergoing total thyroidectomy are suitable for inclusion. In all patients, undergoing total thyroidectomy infrared fluorescence imaging, using a per-operative intravenous injection of 7.5 mg ICG, will be tested on feasibility and imaging characteristics.

Description:

In this study, the feasibility of the use of NIR fluorescence imaging for the identification of the parathyroid glands during thyroid surgery will be explored.

Per-operatively: The surgery will start as usual. When the surgeon would normally search for the parathyroid glands, 7.5 mg of ICG will be administered intravenously through the infusion in the patients arm. An intravenous administration is chosen because of the minimal invasive nature and results of the described earlier case series in which ICG was also administered via peripheral infusion. Directly after that, the fluorescence system can be switched to fluorescence mode. The surgeon will determine whether the parathyroid glands are visible now. If needed, due to washout, a second dose of 7.5 mg of ICG can be administered. After identification of the parathyroid glands, surgery will continue as in the standard situation, until there is a desire to visualize the parathyroid glands again, then another dose of ICG can be given. Time until first identification of the parathyroid glands and total surgical time will be measured. After complete removal of the thyroid, another 7.5 mg of ICG will be administered intravenously to visualize the vascularization of the parathyroid gland. The intensity will be subjectively scored: 1 parathyroid black after injection of ICG, 2 partially vascularized, or 3 parathyroid is green; well vascularized. The fluorescence system will be used to record the whole procedure. Directly after the procedure the researcher will ask the surgeon whether he or she thinks the technique is feasible.

Postoperatively: As in standard care, after thyroid surgery, the serum calcium levels will be determined. Low calcium levels can indicate misidentification of parathyroid glands. These calcium levels are determined only in patients after total thyroidectomy on day 1, 2 and after two weeks. Also TSH will be determined after two weeks as in standard care. The thyroid specimen will be send to pathology. In the specimen, the pathologist will search for parathyroid glands, as is standard care. Furthermore, video recordings will be analyzed, quantifying the fluorescence signal compared to the background: measuring the Target to Background Ratio. Also, in these video recordings the time until visualization of the parathyroid glands will be reassessed by an independent expert.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: March 12, 2018
• Est. primary completion date: February 1, 2018
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

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

• i.v. heparin injection in the last 24h (LMWH not contraindicated)

• Not willing to participate

Related Conditions & MeSH terms

• Thyroid Disease
• Thyroid Diseases

Intervention

Device:
• NIRF imaging in thyroid surgery
a fluorescence imaging system and 7.5 mg of ICG will be used to visualize the parathyroids glands.

Locations

Country	Name	City	State
Netherlands	Maastricht University Medical Center	Maastricht	Limburg

Sponsors (1)

Lead Sponsor	Collaborator
Maastricht University Medical Center

Country where clinical trial is conducted

Netherlands, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Quantitative measurement of fluorescence signal related to parathyroid function	Quantitative measurement of fluorescence signal using Target to Background Ratio (TBR) is used, combined with parameters of parathyroid function, namely Calcium levels postoperatively day 1 and day 2, and week 2 in patients after total thyroidectomy (as in standard care), and TSH in patients after total thyroidectomy 2 weeks postoperatively (as in standard care).	up to 2 weeks
Primary	Time to identification of parathyroid glans	Can the parathyroid glands be identified earlier with NIRF light? Time until identification in NIRF and white light will be compared.	during surgery
Secondary	Total surgical time		From incision until closure
Secondary	Histology: are parathyroid glands in the specimen? (as in standard care)	immediately after surgery, the thyroid specimen will be send to the pathology department for histological examination as in standard care, with extra attention on wether there are parathyroid glands in the specimen.	assessment within 1 week after surgery
Secondary	Subjective opinion surgeon about the usefulness of the technique		Immediately after surgery
Secondary	Intra-operative complications due to the use of the technique		during surgery