Assessing Parathyroid Glands Vascularisation by ICG Fluoroscopy

The Use of Indocyanine Green Fluorescence to Assses the Vascularisation of the Parathyroid Glands During Thyroid Surgery

Evaluate parathyroid gland perfusion during total thyroidectomy or thyroid totalisation surgery. Create an objective basis for the decision whether or not to transplant the parathyroid glands. Avoide postoperative serum calcium and parathyroid hormone dosages, and thus abstention of systematic supplementation with calcium and vitamin D in case of good perfusion.

Parathyroid intraoperative indocyanine green (ICG) angiography is a new concept. To simplify the procedure the investigators have classified images into three categories: ICG 2: good blood supply (the gland has a white color); ICG 1: traumatic gland (the gland has a grayish color) and ICG 0: the gland is not vascularized (she has a black color). The investigators have applied the same criteria for visual values. The investigators will randomize 138 patients with good ICG test values (at least one gland that is visually ≥1 and ICG 2): 69 will be subject to the usual postoperative care in the investigators service: 24 hours monitoring with dosage of calcium and PTH in the morning on postoperative day 1 and routine supplementation with Calcimagon D3 Forte (1g Calcium and 800 IU of 25-OH-vitamin D) BD by mouth until postoperative follow-up appointment, which takes place between day 10 and 15. Depending on the results of blood tests patients will also be given Rocaltrol substitution (1, 25-OH-Vitamin D) 0.5mcg BD. The remaining patients will be monitored 24 hours in hospital looking for clinical signs and symptoms of hypocalcemia but without any blood dosage or systematic supplementation. If signs and / or symptoms of hypocalcemia develop (tingling, muscle spasms, Chvostek sign), a blood test will be performed and patients will be substituted by the usual protocol. All patients will be reviewed at 10 - 15 days of the intervention with the relevant balance sheet.

Parathyroid gland angiography, Parathyroid gland indocyanine green angiography, Parathyroid gland indocyanine green fluoroscopy

In patients with at least one well perfused parathyroid gland on ICG parathyroid angiography, no postoperative parathyroid dosage and supplementation will be done. Calcium and parathormone dosage will be done 10 days after surgery.

In those patients in whom at least on of the four parathyroid glands is well perused, postoperative parathyroid function test and parathyroid supplementation will be done. Calcium and parathormone dosage will be done at 24 hours and 10 days after surgery. Prophylactic supplementation of calcium and Vitamin D will be given.

The patients will be clinically followed for 24 hours after surgery and caclium and parathormone dosage will be done at ten days after surgery. No supplementation will be given.

Injection of 3,5 mL of indocyanine green intravenously and perform angiography of parathyroid glands after thyroid removal.

Supplementration with Calcimagon D3 Forte (1gr Calcium and 800 IU of 25-OH-vitamin D) from surgery day to up to 10 days afeter surgery.

All patients will be reviewed at 10-15 days after surgery and blood tests will be done. Investigators will check the number of patients with serum calcium and parathyroid hormone in normal ranges at ten days after surgery in both arms of the study. Low parathyroid function will be diagnosed when corrected calcium < 2mmol/l, and PTH < 1.1 pmol/l.

Number of patients with good calcium and parathormone values at 10 days after surgery without calcium and vitamin D supplementation in the selected group.

Compare the costs of both procedures: standard procedure and new treatment and then evaluate the economic impact of this preventig mesure, and the possibility to undergo ambulatory surgery

Inclusion Criteria: Adult patients undergoing total thyroidectomy or a totalisation thyroid procedure. Patients capable of understanding and able to understand the study. Values visually 2 and ICG 2 Exclusion Criteria: Parathyroid disease or prior parathyroidectomy Lack of informed consent Altered mental status of the patient. ICG values <2.

Vidal Fortuny J, Sadowski SM, Belfontali V, Guigard S, Poncet A, Ris F, Karenovics W, Triponez F. Randomized clinical trial of intraoperative parathyroid gland angiography with indocyanine green fluorescence predicting parathyroid function after thyroid surgery. Br J Surg. 2018 Mar;105(4):350-357. doi: 10.1002/bjs.10783. Epub 2018 Feb 6.