Comparison of indocyanine green angiography vs intraoperative parathyroid hormone in early prediction of risk of post-thyroidectomy hypocalcemia: a prospective cohort study

Introduction

Indocyanine green (ICG) angiography is the 'real-time intraoperative imaging' technique used to reduce the chances of hypoparathyroidism in post-thyroidectomy patients. In our study, the authors predicted the risk of early post-thyroidectomy hypocalcemia by intraoperative evaluation of parathyroid gland perfusion by ICG angiography.

Materials and methods

In patients who underwent total thyroidectomy, ICG angiography was done using the SPY PHI imaging system (Stryker). Post-thyroid specimen removal, scoring of parathyroids was done in spy contrast mode. All 4 or <4 visualized parathyroids were scored for vascularity with the highest score of 8. Serum ionized calcium was done 6 h postsurgery and on the morning and evening of postoperative days 1 and 2. Calcium supplements were given to only those who developed clinical or severe biochemical hypocalcemia.

Results

Out of 60, postoperative hypocalcemia was noted in 41 patients. Total ICG score ≤5 was seen in 34 patients, out of which 28 developed postoperative hypocalcemia showing PPV 82.3% and diagnostic accuracy of 68.3% while iPTH (4.28 pmol/l) showed PPV 76.7 and diagnostic accuracy 70 %. In eight patients, none of the glands was scored as 2 (White) and all these patients developed hypocalcemia requiring calcium infusion.

Conclusion

The absence of visualization of at least 1 well-perfused (score 2) gland on ICG angiography is highly predictive of hypocalcemia and the majority of patients with total ICG score ≤5 developed hypocalcemia in the immediate postoperative period. ICG is a good predictor of the absence of hypoparathyroidism after thyroidectomy and is comparable to iPTH in the prediction of post-thyroidectomy hypocalcemia.

PHPT with Pancreatitis: Atypical Presentation of PHPT

Background

Primary hyperparathyroidism (PHPT) is rarely associated with the occurrence of acute or chronic pancreatitis, requiring complex perioperative management. This study aimed to assess the prevalence and disease characteristics of pancreatitis in PHPT.

Materials and Methods

This study is a clinicopathological analysis of the medical records of patients who were diagnosed with PHPT with pancreatitis between 1989 and 2021 in the Endocrine Surgery department, SGPGI, Lucknow.

Results

Out of 548 PHPT cases, 44 (8.03%) were found to be associated with pancreatitis. The mean age was 33.57 years (15-65 years); 5 were ≤20 years, while 26 were ≤30 years of age. There were 27 males and 17 females. Twenty-one cases were of acute (11 acute, nine recurrent acute, one acute on chronic), whereas 23 were of chronic pancreatitis (six chronic calcific pancreatitis). The major clinical presentation of PHPT with pancreatitis was abdominal pain (65.91%). The mean number of attacks per patient in recurrent acute pancreatitis was two. Mean PTH levels were 68.19 pmol/L. The mean tumor size (in the largest dimension) was 2.79 ± 1.4 cm while the mean tumor weight was 4.91 g. Nephrolithiasis was associated with 25 cases. An association with multiple endocrine neoplasia type 1 syndrome was seen in one case. The final histopathological diagnosis was parathyroid carcinoma in two, hyperplasia in three, and parathyroid adenoma in 39 cases. Normocalcemia was seen in 27.2%, hypercalcemic crisis in 15.9%, and 25% of patients required semi-emergency parathyroidectomy. The outcome was favorable in all, as none had any further attacks of pancreatitis.

Conclusion

In our study, the prevalence of pancreatitis in PHPT cases was 8.03%. The majority of patients were young. Normocalcemia was seen in 12 patients, so even if calcium levels are normal, PHPT should be suspected in young patients with pancreatitis. Parathyroidectomy resulted in the complete resolution of symptoms of pancreatitis in all 44 patients.