The aim of this study is to develop a standardized and user-independent imaging workflow model for autofluorescence and quantified fluorescence angiography with Indocyanine Green (ICG) of the parathyroid glands of children. For this purpose, all pediatric patients will undergo thyroid surgery with the use of autofluorescence and quantified ICG-fluorescence.

This study could be the first step in reducing the rate of postoperative hypocalcemia in children, by using fluorescence angiography during pediatric thyroid surgery.

Background:

Children with thyroid cancer have excellent survival rates. However, postoperative hypocalcemia, due to inadvertent excision of the parathyroid glands or damage to their vasculature during thyroid surgery, is a severe complication which occurs in 24% - 67% of the children with thyroid cancer and causes lifelong reduced quality of life and increased morbidity rates. In adults, intraoperative identification of the parathyroid glands with autofluorescence and assessment of their perfusion using quantified ICG-fluorescence angiography has shown to reduce postoperative hypocalcemia. However, in children no studies regarding quantified fluorescence of the parathyroid glands have been conducted. There is a clear need for surgical techniques to identify and preserve the parathyroid glands during thyroid surgery in children.

Therefore, the aim of this study is to develop a standardized imaging workflow model for autofluorescence and quantified ICG-angiography of the parathyroid glands in children. This workflow model can be the first step in reducing the rate of postoperative hypocalcemia in children.

Study design:

This will be a prospective, observational, multicenter, feasibility study. The aim is to generate the patterns of intraoperative autofluorescence and quantified ICG-fluorescence angiography of the parathyroid glands in children, resulting in a user-independent, standardized imaging workflow model for autofluorescence and quantified ICG-angiography of the parathyroid glands of children.

Inclusion Criteria:

1. Patients <18 years
2. Patients undergoing total thyroidectomy (for any indication)
3. Patients undergoing lobectomy for the suspicion of a malignancy, with a subsequent completion thyroidectomy
4. Written informed consent (from parents/caregivers, patients or both, see chapter 6.0)

Exclusion Criteria:

1. Patients with preoperative hypo - or hypercalcemia, treated for hypo- or hypercalcemia, (chronic) renal disease, kidney transplantation or any disorder that requires calcium supplementation (other than standard preoperative calcium supplementation for a total thyroidectomy).
2. Patients with known allergy to ICG or iodinated contrast
3. Pregnancy or breastfeeding
4. Patients with severe liver dysfunction
5. Preterm neonates
6. Newborn infants with an indication for exchange transfusion for severe neonatal hyperbilirubinemia

Patients under 18 years old that will undergo total thyroidectomy for any indication or lobectomy for the suspicion of a malignancy will be checked for the inclusion and excusion criteria. If eligible, patients will be asked for written informed consent.

Request for data sharing will be considered by the project leaders upon written request. Deidentified participant data will be made available after receipt of a written proposal and a signed data sharing agreement. Furthermore, an amendment will be handed in to the MEC for ethical approval before starting this additional research.

The study protocol will be published in a international, peer-reviewed journal with open acces, during the study period.