The purpose of the investigation is to study if the use of Fluobeam®-LX to identify parathyroid glands through autofluorescence during thyroid surgery, may reduce the risk of postoperative hypoparathyroidism, defined as low PTH in patients undergoing total thyroidectomy

Temporary and permanent hypoparathyroidism is probably the most important complication of total thyroidectomy. The rate of permanent hypoparathyroidism in quality registries are in the range of is 5-7 percent of patients undergoing surgery.

Patients operated on benign disease with total thyroidectomy, and who suffer from permanent hypoparathyroidism (defined as medication with active Vitamin D analogue therapy for more than 6 months, are at increased risk of renal insufficiency. They also have, for unclear reasons, an increased risk of suffering from malignancy, compared to patients without this complication. Patients with known ischemic heart disease before surgery also have an increased risk of suffering a new episode of cardiovascular disease. Finally, patients with permanent hypoparathyroidism have an increased risk of mortality compared to patients without this complication.

If, by using a technique for autofluorescence (Fluobeam® -LX), one can more accurately identify and avoid damage to the parathyroid glands during the surgical procedure, this would be of great importance for patients undergoing total thyroidectomy for thyroid disease.

Patients undergoing total thyroidectomy are randomized to the use of Fluobeam® -LX to detect the parathyroid glands through autofluorescence during thyroid surgery, or clinical evaluation only (control). Outcome is evaluated by parathyroid hormon (PTH) levels the first postoperative day and the need for medication with calcium and Vitamin D up to 6 months postoperatively.

Inclusion Criteria:

Patients with thyroid disease planned for total thyroidectomy regardless of diagnosis

Exclusion Criteria:

• Previous thyroid surgery
• Previous parathyroid surgery
• Concurrent parathyroid surgery
• Renal insufficiency
• Pregnancy
• Breast feeding
• Allergy (contrast agent, iodine)
• Inability to understand study information
• Patient unable to participate in planned follow-up program

All individual participant data (IPD) that underlie results in a publication. Individuals are de-identified

Starting 12 months after publication and for five years

Researchers within the medical community The principal investigator or the Central Contact Backup will review requests.

The participant is not informed of the assigned group, whereas the the care giver (surgeon) is informed due to the use (or not) of the Fluobeam®-LX.

Randomization is performed 1: 1 in blocks of 10 via the Eurocrine quality register platform.