Use of four-dimensional computed tomography to aid parathyroid localisation in primary hyperparathyroidism in British surgical practice.

Introduction: Four-dimensional computed tomography (4DCT) has emerged as an effective imaging modality to aid parathyroid localisation before surgery. Following a service change in 2018, we evaluated the accuracy of 4DCT to lateralise culprit parathyroid glands causing primary hyperparathyroidism (PHPT) in patients undergoing parathyroid surgery in our centre.

Methods: A total of 117 patients underwent 4DCT before parathyroidectomy for PHPT in NHS Grampian between March 2018 and January 2023, of whom 112 underwent first-time operations. Results of imaging, histopathology and surgery type along with biochemical follow-up were evaluated retrospectively to assess the sensitivity and specificity of 4DCT imaging.

Results: In our centre, 4DCT imaging showed results comparable with those reported previously, with 77.6% sensitivity to lateralise to one side of the neck, 89.1% specificity and an overall accuracy of 83.5%. A total of 58% of patients underwent targeted parathyroidectomy. At three- to six-month follow-up, 94.5% had achieved biochemical cure; 4DCT identified culprit lesions in four out of five patients undergoing reoperation. Age and corrected calcium did not affect accuracy of 4DCT.

Conclusions: 4DCT is an effective first-line imaging modality before first-time parathyroidectomy for PHPT in patients aged >60 years as well as in cases of reoperation. Use as the first-line imaging modality in younger patients may reduce overall radiation exposure by minimising the need for additional imaging, but further study is needed in this age group.