Impact of near-infrared fluorescence imaging plus indocyanine green fluorescence on postoperative hypoparathyroidism rates after total thyroidectomy and central neck lymph node dissection.

BACKGROUND: Patients with thyroid carcinoma often undergo cervical lymph node dissection, which is associated with high rates of both transient and permanent postoperative hypoparathyroidism. The impact of near-infrared fluorescence imaging + indocyanine green (ICG) fluorescence on postoperative hypoparathyroidism rates after total thyroidectomy and central neck lymph node dissection was evaluated. METHODS: All patients undergoing surgery between January 2019 and March 2023 were included and divided into three groups: a control group (parathyroid glands identified visually), a near-infrared fluorescence imaging alone group, and a near-infrared fluorescence imaging + ICG fluorescence group. The primary outcome was the transient and permanent postoperative hypoparathyroidism rates. Secondary outcomes were: length of surgery and number of parathyroid glands identified, inadvertently resected, and autotransplanted. RESULTS: A total of 131 patients were included in the study (47 in the control group, 45 in the near-infrared fluorescence imaging alone group, and 39 in the near-infrared fluorescence imaging + ICG fluorescence group). The transient hypoparathyroidism rate was 48.9% in the control group, 37.8% in the near-infrared fluorescence imaging alone, and 5.1% in the near-infrared fluorescence imaging + ICG fluorescence group (P < 0.0001), while the permanent hypoparathyroidism rate was 8.5% in the control group, 2.2% in the near-infrared fluorescence imaging alone group, and 0% in the near-infrared fluorescence imaging + ICG fluorescence group (P = 0.096). The number of parathyroid glands identified was 159 of 188 in the control group, 165 of 180 in the near-infrared fluorescence imaging alone group, and 149 of 156 in the near-infrared fluorescence imaging + ICG fluorescence group (P = 0.002). Inadvertent resection of parathyroid glands occurred for 29 of 188 in the control group, 15 of 180 in the near-infrared fluorescence imaging alone group, and 7 of 156 in the near-infrared fluorescence imaging + ICG fluorescence group (P = 0.002), with subsequent parathyroid gland autotransplantation for 2 of 29 in the control group, 2 of 15 in the near-infrared fluorescence imaging alone group, and 3 of 7 in the near-infrared fluorescence imaging + ICG fluorescence group (P = 0.040). There was no difference in the median operating time between groups. CONCLUSION: The use of near-infrared fluorescence imaging + ICG fluorescence decreased both transient and permanent hypoparathyroidism rates in patients undergoing total thyroidectomy and central neck lymph node dissection.

Is There Any Reliable Predictor of Functional Recovery Following Post-thyroidectomy Vocal Fold Paralysis?

BACKGROUND: Predicting definitive outcomes of post-thyroidectomy vocal fold paralysis (VFP) is challenging. We aimed to identify reliable predictors based on intraoperative neuromonitoring (IONM) and flexible fiberoptic laryngostroboscopy (FFL) findings. METHODS: Among 1172 thyroid operations performed from April to December 2021, all patients who exhibited vocal fold paralysis (VFP) at post-operative laryngoscopy were included. IONM data, including type of loss of signal (LOS), were collected. Patients underwent FFL, with arytenoid motility assessment, at 15, 45 and 120 days post-operatively. Patients were divided into two groups: those who recovered vocal fold motility (VFM) by the 120th post-operative day (recovery group) and those who did not (non-recovery group). RESULTS: Fifty-nine VFP cases (5.0% of total patients) met the inclusion criteria. Eight patients were lost at follow-up and were excluded. Overall, 9 patients were included in the non-recovery group (0.8% of total patients) and 42 in the recovery group. Among various predictive factors, only arytenoid fixation (AF) at the 15th post-operative day and Type I LOS were significant predictors for no VFM recovery (p = 0.007, RR = 9.739, CI:1.3-72.3 and p = 0.001, RR = 9.25, CI:2.2-39.3 for AF and Type I injury, respectively). The combination of type of LOS and arytenoid motility at the 15th post-op day yielded satisfactory predictive values for the progression of transient VFP to permanent. CONCLUSIONS: Arytenoid motility at the 15th post-op day and type II LOS are associated with recovery of VFM. Type of LOS and FFL could be included in the follow-up protocols of patients with VFP to reliably predict clinical outcomes.