case_images: PMC10067725_01
case_images: Preoperative imaging modalities were used to find and locate the parathyroid tissues. (A) US revealed two hypoechoic lesions with volumes of 0.55 cm x 0.45 cm and 0.55 cm x 0.35 cm (arrow) located at the dorsal area of right lobe of thyroid gland. (B) In CEUS, both lesions appeared as characteristics of parathyroid tissues (fast in the early phase, slow out in the late phase, and higher enhancement with a long enhancement time). (C) 99mTc-MIBI planar early (15 min) and delayed (3 h) static images showed that there is no tissue with focal tracer accumulation presented at the primary surgery site of neck. (D) 99mTc-MIBI planar early (15 min) and delayed (3 h) static images showed that there is no focal tracer accumulation at the autograft site. (E) The axial CT (E1 and E2) and SPECT/CT (E3 and E4) images showed soft-tissue masses with marked MIBI uptake in the left upper mediastinum (arrows). US, ultrasound; CEUS, contrast-enhanced ultrasound; 99mTc-MIBI, 99mTc-sestamibi.
case_images: fsurg-10-1135596-g001.jpg
case_images: PMC10067725_01_fsurg-10-1135596-g001.jpg
case_images: F1
case_images: In the dorsal area of right thyroid lobe, ultrasound (US) detected two hypoechoic formations with volumes of 0.55 cm x 0.45 cm and 0.55 cm x 0.35 cm (Figure 1A), which presented as a vascularization pattern of parathyroid lesions (fast-in, slow-out, and higher-enhancement with long enhancement time) when examined by using contrast-enhanced ultrasound (CEUS) (Figure 1B). 99mTc-sestamibi (99mTc-MIBI)/single photon emission computed tomography (SPECT) did not find any tracer accumulation in the sites of neck and autograft but revealed a nodule (1.5 cm x 1.0 cm) with tracer uptake in the mediastinum (Figure 1C).
case_images: Excision of suspected recurrent parathyroid tissues and pathologic analysis. (A) Two suspected parathyroid lesions (A1-2, arrow) located at the dorsal area of right lobe of thyroid gland were resected. One suspected parathyroid lesion (A3, arrow) located on the central region of right neck was found during exploration, and then clearance of the central neck compartment was performed. A thoracoscopic surgery also was performed to remove a mediastinal parathyroid gland (A4, arrow). (B) Histopathology (hematoxylin-eosin staining  x200) showed that the lesions at the site of primary surgery (B1-3) were consistent with the pathological features of parathyromatosis. The resected mediastinal parathyroid gland had demonstrated nodular hyperplasia of parathyroid tissue, which was well differentiated (B4). (C) An extensive surgery that involved the excision of suspected parathyroid lesions and the clearance of the central neck compartment was performed, and the postoperative picture had been shown. (D) A thoracoscopic surgery to remove mediastinal parathyroid gland had been performed, and the postoperative picture had been shown.
case_images: fsurg-10-1135596-g002.jpg
case_images: PMC10067725_01_fsurg-10-1135596-g002.jpg
case_images: F2
case_images: Cervicotomy was performed to remove the suspected recurrent parathyroid tissue and the surrounding tissue around the right thyroid lobe (Figure 2A1-3). Besides two lesions of the neck detected by US and CEUS, another lesion was found in the central compartment of the neck during the reoperation (Figure 2A3), which made us believe that the hyperplastic parathyroid tissues at this region mainly resulted from a secondary implantation into the surrounding tissues of the damaged parathyroid gland during the initial operation. Therefore, the clearance of the central neck compartment also was performed (Figure 2C). A thoracoscopic surgery was performed to remove the hypertrophic mediastinal parathyroid gland (Figure 2A4). According to the histological study, three lesions of parathyroid tissues at the site of primary surgery are represented by diffuse-nodular hyperplasia from dark main cells and nodular hyperplasia shown in fibroadipose tissues, and these lesions do not have their own capsule and suture material surrounded by nodular hyperplasia (Figure 2B1-3). Pathologic analysis of the resected mediastinal parathyroid gland showed nodular hyperplasia of parathyroid tissue, which was well differentiated (Figure 2B4).
case_images: 99mTc-MIBI/SPECT was used to demonstrate whether the suspected parathyroid tissues had been missed. (A) 99mTc-MIBI planar early (15 min) and delayed (3 h) static images showed that there is no tissue with focal tracer accumulation that presented in the primary surgery site of neck. (B) A weak focal tracer accumulation had presented in the autograft site. (C) The axial CT (C1 and C22) and SPECT/CT (C3 and C4) images showed no tissue with MIBI uptake in the mediastinum. 99mTc-MIBI, 99mTc-sestamibi; CT, computed tomography.
case_images: fsurg-10-1135596-g003.jpg
case_images: PMC10067725_01_fsurg-10-1135596-g003.jpg
case_images: F3
case_images: Cervicotomy was performed to remove the suspected recurrent parathyroid tissue and the surrounding tissue around the right thyroid lobe (Figure 2A1-3). According to the histological study, three lesions of parathyroid tissues at the site of primary surgery are represented by diffuse-nodular hyperplasia from dark main cells and nodular hyperplasia shown in fibroadipose tissues, and these lesions do not have their own capsule and suture material surrounded by nodular hyperplasia (Figure 2B1-3). On the fifth day after operation, 99mTc-MIBI/SPECT was performed, and no suspected parathyroid tissues were detected in the neck or the mediastinum (Figures 3A,C). Interestingly, a weak focal tracer accumulation had presented in the autograft site (Figure 3B), indicating the existence of functional parathyroid tissues in the autograft site.