Department of Endocrinology, Seth GS Medical College and KEM Hospital, Mumbai, India.
Department of Radiology, Seth GS Medical College and KEM Hospital, Mumbai, India.
Clin Endocrinol (Oxf). 2017 Dec;87(6):791-798. doi: 10.1111/cen.13406. Epub 2017 Jul 31.
Radiation exposure to neck by four-dimensional computerized tomography (4DCT) is relatively high and limits its use as a first-line investigation in evaluation of primary hyperparathyroidism (PHPT). Radiation exposure can be reduced by restricting the number of CT phases. Our aim was to study the performance of 4DCT in cohort of surgery-naïve PHPT patients, and to evaluate percentage enhancement as an objective radiological index to discriminate parathyroid lesions (adenoma/hyperplasia) from thyroid tissue and lymph nodes.
Retrospective study of 49 PHPT patients {(44 single-gland diseases (SGD) and five multiple-gland disease (MGD)} who underwent 4DCT (unenhanced, early arterial, early venous and delayed venous phase) pre-operatively. Two radiologists who were blinded to surgical location of parathyroid lesions examined the scans. Attenuation values were recorded for parathyroid lesions (n=50), thyroid gland (n=50) and lymph nodes (n=12) in different phases. Percentage enhancement for different phases was calculated as "(HU in a specific enhanced phase-HU in unenhanced phase)/HU in unenhanced phase" ×100.
Inter-rater reliability between the two radiologists was 0.83 (Cohen's kappa). In SGD, sensitivity and PPV were 93.18% and 98.8% for lateralization, and 89.77% and 95.18% for quadrant localization, respectively. In MGD, 4DCT showed 50% sensitivity and 100% PPV. Percentage arterial enhancement showed highest area under curve (AUC=0.992) for differentiation of parathyroid lesions from thyroid tissue and lymph nodes. A cut-off value of 128.9% showed 95.8% sensitivity and 100% specificity for the identification of parathyroid lesions.
We propose that percentage arterial enhancement can be used as an objective radiological index for accurate identification of parathyroid adenoma/hyperplasia.
颈部四维计算机断层扫描（4DCT）的辐射暴露相对较高，限制了其作为原发性甲状旁腺功能亢进症（PHPT）评估的一线检查手段。通过限制 CT 相位的数量可以降低辐射暴露。我们的目的是研究 4DCT 在未经手术的 PHPT 患者中的表现，并评估百分比增强作为客观的影像学指标，以区分甲状旁腺病变（腺瘤/增生）与甲状腺组织和淋巴结。
回顾性研究了 49 例 PHPT 患者（44 例单灶疾病（SGD）和 5 例多灶疾病（MGD）），这些患者均接受了术前 4DCT（未增强、早期动脉期、早期静脉期和延迟静脉期）检查。两位对甲状旁腺病变的手术位置不知情的放射科医生检查了扫描结果。记录了不同相位下甲状旁腺病变（n=50）、甲状腺（n=50）和淋巴结（n=12）的衰减值。不同相位的百分比增强值计算为“（特定增强相的 HU 值-未增强相的 HU 值）/未增强相的 HU 值”×100。
两位放射科医生之间的组内一致性为 0.83（Cohen's kappa）。在 SGD 中，侧位的灵敏度和阳性预测值（PPV）分别为 93.18%和 98.8%，象限定位的灵敏度和 PPV 分别为 89.77%和 95.18%。在 MGD 中，4DCT 的灵敏度为 50%，PPV 为 100%。动脉期百分比增强对区分甲状旁腺病变与甲状腺组织和淋巴结的曲线下面积（AUC）最高（AUC=0.992）。128.9%的截断值对识别甲状旁腺病变的灵敏度为 95.8%，特异性为 100%。
我们提出，动脉期百分比增强可以作为准确识别甲状旁腺腺瘤/增生的客观影像学指标。
