Initial Experience with Indocyanine Green Fluorescence during Total Thyroidectomy in Mexico: The Postoperative Hypocalcemia Index Decreases?

Background: Postoperative hypocalcemia is the most common complication of total thyroidectomy. Recently, new techniques have emerged for identifying the parathyroid glands, such as indocyanine green (ICG) fluorescence, which has been well accepted by various groups of expert surgeons internationally. In this study, we use this technique to assess the viability of the parathyroid glands after total thyroidectomy using the angiographic images it provides. Methods: This is a cohort study that includes patients who underwent total thyroidectomy during the pandemic period in 2020 using ICG fluorescence. These patients were evaluated for transient and permanent (>6 months) hypocalcemia postoperatively. Additionally, the results were compared with historical controls, which included patients treated by a low-volume thyroid surgeon (group A) and those treated by a high-volume thyroid surgeon (group B). Several variables were included and analyzed between the groups, such as the number of auto-transplanted parathyroids, postoperative serum calcium levels, and symptoms of hypocalcemia. The main aim of the study was to determine whether the use of ICG fluorescence is associated with a lower rate of postoperative hypocalcemia. Results: A total of 18 patients were operated using ICG fluorescence. Of them, 14 (75%) cases were females and median age was 54 ± 13.5 years. 29 patients were included in group A (operated by a low-volume thyroid surgeon) and 50 patients in group B (by a high-volume thyroid surgeon). Autotransplantation was not necessary in ICG group compared with 3 and 1 in the groups A and B, respectively. Thyroid cancer was confirmed in 58 (59%) of cases by histopathology. Postoperative calcium levels were higher in ICG fluorescence group compared with groups A and B from day 1 to 6 months of follow-up (p = NS). Statistical analysis showed a significant difference in transient hypocalcemia and permanent hypoparathyroidism rates (p = 0.011 and p = 0.002, respectively) when contrasted between groups. The sub-analysis showed that ICG fluorescence reached slight significance for transient hypocalcemia but did not achieve statistical significance for permanent hypocalcemia when compared to the high-volume surgeon group (Group B) (p = 0.039 and p = 0.28, respectively). Conclusions: ICG fluorescence technique was associated with lower incidence of postoperative hypocalcemia, especially when it is compared to low-volume thyroid surgeon.