4D-CT as a second line preoperative localization test for the evaluation of primary hyperparathyroidism.

Introduction: Four-dimensional computerized tomography (4D-CT) offers a good sensitivity for the localization of the pathological gland responsible of primary hyperparathyroidism. The aim was to evaluate its results as a second line preoperative localization test after inconclusive or discordant results of usual preoperative studies.

Material And Methods: Observational retrospective study that included all patients intervened for primary hyperparathyroidism with 4D-CT scan as preoperative study, from 1st October 2016 to 1st October 2021, in a tertiary referral centre. The results of 4D-CT, cervical ultrasound, and Nuclear Medicine explorations (scintigraphy, SPECT and SPECT-CT) were compared with the gold standard of the surgical exploration and the pathological result. The correct lateralization and the approximate localization rates of the pathological gland were evaluated.

Results: A total of 64 patients were analysed, with a 93,8% (60/64) remission rate. 4DCT showed a correct lateralization in 57,8% (37/64) of the cases and revealed the approximate localization of the gland in 48,4% (31/64) of the cases. The cervical ultrasound had a rate of 31,1% (19/61) and 18% (11/61) for the correct lateralization and approximate localization, respectively, compared to 34,9% (22/63) and 28,6% (18/63) in Nuclear Medicine explorations, and 32,7% (16/49) and 24,5% (12/49) in SPECT-CT. These differences were statistically significant.

Conclusion: 4D-CT demonstrated acceptable results for the localization of the lesions responsible of primary hyperparathyroidism, thus its use should be considered with the absence of localization in routinely studies.