RT Journal Article
SR Electronic
T1 A Simple Formula to Estimate Parathyroid Weight on 4D-CT, Predict Pathologic Weight, and Diagnose Parathyroid Adenoma in Patients with Primary Hyperparathyroidism
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1690
OP 1697
DO 10.3174/ajnr.A6687
VO 41
IS 9
A1 Yeh, R.
A1 Tay, Y.-K.D.
A1 Dercle, L.
A1 Bandeira, L.
A1 Parekh, M.R.
A1 Bilezikian, J.P.
YR 2020
UL http://www.ajnr.org/content/41/9/1690.abstract
AB BACKGROUND AND PURPOSE: Parathyroid gland weight is a clinically relevant parameter used to diagnose parathyroid adenomas intraoperatively. We evaluated the accuracy of a formula to estimate parathyroid weight on preoperative 4D-CT.MATERIALS AND METHODS: A single-institution retrospective study was performed in patients with primary hyperparathyroidism who underwent 4D-CT between January 2013 and December 2014 with subsequent parathyroidectomy and surgical cure. All patients had correct localization of a solitary parathyroid adenoma. The longest 3 dimensions of all identified parathyroid glands were measured on CT, and weight was estimated using the formula: weight4D-CT (mg) = 1 mg/mm3 × Length (mm) × Width (mm) × Height (mm) × π/6. We correlated weight4D-CT with pathology specimen weight (weightpathology). Using receiver operating characteristic analysis, we estimated the performance of weight4D-CT to discriminate a parathyroid adenoma from normal glands on 4D-CT and determined the optimal threshold based on the Youden index.RESULTS: One hundred sixteen patients (85 women, 31 men) were evaluated. Weight4D-CT was shown to be strongly correlated with weightpathology as demonstrated by Spearman ρ = 0.73 (P < .01), concordance correlation coefficient = 0.92 (95% CI, 0.89–0.94), and Cronbach α = 0.96. The performance of weight4D-CT for the diagnosis of parathyroid adenoma was excellent, with an area under the curve of 0.955 (95% CI, 0.925–0.985; P < .001). Based on the Youden index, the optimal threshold was >50 mg, with a sensitivity of 96.7% and a specificity of 95.7%.CONCLUSIONS: Radiologists can accurately estimate parathyroid adenoma weight on 4D-CT. This metric is highly correlated with pathologic weight, and a threshold cutoff of >50 mg can be used to distinguish parathyroid adenoma from normal glands.AUCarea under the curveIQRinterquartile rangeROCreceiver operating characteristic