甲状旁腺功能亢进的定位诊断

比较了８５例临床诊断为甲状旁腺功能亢进的患者使用（２０１）Ｔｌ／（９９ｍ）Ｔｃ双核素减影技术、（９９ｍ）Ｔｃ－ＭＩＢＩ和Ｂ型超声做病灶术前定位的结果。术中共发现９９个病灶，双核素显像检出４９个病灶，Ｂ超发现６７个病灶，灵敏度分别为５０％和６７％。其中８例患者用（９９ｍ）Ｔｃ－ＭＩＢＩ检查的灵敏度为６７％（６／９）；对异位甲状旁腺病灶核素显像的灵敏度为８４．６％（１４／１７），Ｂ超为４１％（７／１７）。     

Parathyroid glands: combination of (99m)Tc MIBI scintigraphy and US for demonstration of parathyroid glands and nodules

PURPOSE: To determine the appropriate choice of imaging techniques for localization of nodular lesions of parathyroid glands. MATERIALS AND METHODS: First, computed tomographic (CT), magnetic resonance (MR), ultrasonographic (US), and technetium 99m methoxyisobutyl-isonitrile (MIBI) scintigraphic images in 49 patients with primary hyperparathyroidism were retrospectively evaluated. A single-blind, prospective study that included 16 patients with primary hyperparathyroidism was then conducted. MR, US, scintigraphic, and color Doppler US images of the neck were obtained and analyzed. RESULTS: In the retrospective study, CT, MR imaging, and US had low sensitivity (13%, 17%, and 27%, respectively) and specificity (39%, 65%, and 65%, respectively). Scintigraphy had 57% sensitivity and 85% specificity. In the prospective study, the use of latest-generation MR and US equipment and the participation of experienced operators led to improved sensitivity and specificity for these techniques. The combination of US and scintigraphy resulted in improved sensitivity (96%), specificity (83%), and positive and negative predictive values (88% and 94%, respectively), relative to the results obtained with either method alone. Doppler US was of little help in the setting of small glands. CONCLUSIONS: The combination of (99m)Tc MIBI scintigraphy and US performed by well-trained operators with up-to-date instruments appeared to be the best diagnostic tool for the preoperative diagnosis of parathyroid disease.     

Diagnostic dilemmas in parathyroid scintigraphy.

PURPOSE: Tc-99m MIBI scintigraphy can be useful for preoperative localization of parathyroid adenomas, despite its limited sensitivity. To refine interpretation, the authors conducted prospective reviews of the scintigraphic studies of patients with concomitant thyroid nodular disease and revised the false-negative and false-positive results. MATERIALS AND METHODS: Seventy-seven patients with primary hyperparathyroidism, associated with a solitary parathyroid adenoma, underwent dual-phase MIBI scintigraphy with subsequent injection of Tc-99m pertechnetate before surgery. The false-negative and false-positive scintigraphic findings were identified and revised. RESULTS: After surgery, revision of 19 false-negative scans of the total 77 studies led to the demonstration of an adenoma in seven patients. In five of the seven studies, the adenoma had been overlooked as a result of rapid tracer washout. Two additional small focal lesions would have also been identified if subtraction had been used for differences in contour of the MIBI and pertechnetate images. Four studies were interpreted falsely as abnormal, leading to a positive predictive value of 91%; three were associated with thyroid nodular disease. CONCLUSIONS: Differential washout of MIBI from thyroid and parathyroid tissue is not universal. When MIBI is washed out rapidly from parathyroid adenomas, subtraction of a thyroid image should be performed and differences in contour delineated to localize the adenoma accurately. Some, but not all, thyroid lesions account for the false-positive findings.     

Ectopic parathyroid adenomas located at the carotid bifurcation: the role of preoperative Tc-99m MIBI scintigraphy and the intraoperative gamma probe procedure in surgical treatment planning

PURPOSE: The prevalence of ectopic parathyroid adenoma (PA) is relatively low, despite some studies in which it has been reported to be as high as 20%. Ectopic PA is a frequent cause of surgical failure, and therefore some authors recommend preoperative imaging to localize the condition in patients with primary hyperparathyroid (HPT) disease before initial surgery. METHODS: Two unusual cases of primary HPT caused by an ectopic PA located at the carotid bifurcation are reported. The patients were examined before operation using Tc-99m MIBI scintigraphy and then underwent radioguided surgery using the intraoperative gamma probe technique with injection of a low dose (37 MBq; 1 mCi) of Tc-99m MIBI. RESULTS: The first patient had a history of primary HPT and coexisting multinodular goiter. She had undergone total thyroidectomy in another center, but no enlarged parathyroid gland was found at bilateral neck exploration and serum calcium and parathyroid hormone levels remained elevated after intervention. The patient was referred to our center. A Tc-99m MIBI scan showed a focus of abnormal tracer uptake in the superior left laterocervical region that was thought to be a PA. The next day she underwent radioguided surgery and an 18-mm PA located at the left carotid bifurcation was easily removed through a 2.5-cm skin incision. The second patient was examined in our center before surgery. A neck ultrasound showed a multinodular goiter but no enlarged parathyroid glands. A pertechnectate-MIBI subtraction scan revealed a focus of abnormal Tc-99m MIBI uptake in the right superior laterocervical region that was thought to be a PA. One week later, at radioguided surgery, a 25-mm PA was identified at the right carotid bifurcation and removed successfully. CONCLUSIONS: These data strongly support the utility of preoperative imaging with Tc-99m MIBI in patients with primary HPT before initial neck exploration with the aim of avoiding surgical failure. Furthermore, the intraoperative gamma probe technique seems to be useful to reduce surgical trauma and, possibly, complications in patients with ectopic PA.     

Magnetic resonance imaging (MRI) and technetium-99m-methoxyisonitrile (MIBI) scintigraphy to evaluate the abnormal parathyroid gland and PEIT efficacy for secondary hyperparathyroidism.

PURPOSE: Percutaneous ethanol injection therapy (PEIT) of the abnormal parathyroid gland is an effective treatment in patients with chronic renal failure with dialysis that tends to be unresponsive to medication. To evaluate the efficacy of PEIT, we investigated the correlation between serum intact PTH (iPTH), and the findings of MR imaging and 99mTc-MIBI scintigraphy. MATERIALS AND METHODS: PEIT was performed 32 times in 24 patients with secondary hyperparathyroidism. Both MR imaging and MIBI scintigraphy were performed before and after PEIT. The detectability of parathyroid lesions was evaluated by MRI and MIBI scintigraphy with reference to ultrasound (B-mode) findings (as a standard) and the comparison of each treatment was done between imaging changes and serum iPTH levels. RESULTS: In the small parathyroid glands (< 0.5 ml with US), MR images detected abnormal glands in 74.0% (20/27), and MIBI accumulation was observed in 40.7% of the cases. Whereas, MR images and MIBI showed similar detectability (95.0% vs. 90.0%) to large parathyroid glands (> or = 0.5 ml with US). After PEIT, glands in which ethanol was successfully injected showed decreased signal intensity on T2-weighted images and decreased accumulation of MIBI. MR imaging and MIBI scintigraphy showed almost equivalent high sensitivity in evaluating therapeutic changes (73.3% vs. 76.4%) according to our evaluation category of more than 30% reduction of iPTH as effective. However, the specificity of MR imaging was much higher (100%) than that of MIBI scintigraphy in evaluating therapeutic effects. CONCLUSION: In conclusion, MRI provided better detectability of abnormal parathyroid glands than 99mTc-MIBI scintigraphy. The reduction of high signal intensity area after PEIT on T2-weighted MR images is considered an useful therapeutic evaluation guideline than the reduction of MIBI accumulation on scintigraphy.     

Comparison between MR imaging and 99mTc MIBI scintigraphy in the evaluation of recurrent of persistent hyperparathyroidism

PURPOSE: To compare the sensitivity and positive predictive value of magnetic resonance (MR) imaging and technetium 99m 2-methoxyisobutyl-isonitrile (MIBI) scintigraphy for the detection of hyperfunctioning parathyroid tissue when used alone and in combination in a large patient population with recurrent or persistent hyperparathyroidism (HPT). MATERIALS AND METHODS: In 98 consecutive patients with biochemically proved recurrent or persistent HPT after surgery, MR imaging and 99mTc MIBI study findings were retrospectively reviewed and compared with surgical and histopathologic findings. The sensitivity and positive predictive value of MR imaging and 99mTc MIBI scintigraphy were compared with each other and in combination. RESULTS: In these patients, 130 abnormal parathyroid glands were identified at surgery. The sensitivity and positive predictive value of MR imaging were 82% (95% CI: 75%, 89%) and 89%, respectively; those for (99m)Tc MIBI scintigraphy were 85% (95% CI: 79%, 91%) and 89%. No significant difference was found between MR imaging and 99mTc MIBI scintigraphy for sensitivity (P =.7). The sensitivity and positive predictive value for the detection of abnormal parathyroid tissue on a per-gland basis increased to 94% (95% CI: 90%, 98%) and 98%, respectively, when only one of the two tests was required to be positive. CONCLUSION: MR imaging and 99mTc MIBI scintigraphy have similarly good sensitivity and positive predictive value for the detection of hyperfunctioning parathyroid tissue in patients after surgery. The combination of the two tests provided a substantial increase in sensitivity and positive predictive value.     

Parathyroid scintigraphy with 99mTc-MIBI and 123I subtraction: a comparison with magnetic resonance imaging and ultrasonography

The aim of this study was to evaluate the efficacy of 99mTc-MIBI and 123I subtraction scintigraphy for the detection of abnormal parathyroid glands to be referred for surgical treatment. Thirty-nine consecutive patients, including 35 primary and four secondary cases of hyperparathyroidism, were evaluated. 99mTc-MIBI/123I subtraction scintigraphy (MIBI/I) was performed on all patients, and the results were compared with delayed images of 99mTc-MIBI (D-MIBI), magnetic resonance imaging (MRI) and ultrasonography (US). The overall sensitivity of MIBI/I, MRI, US and D-MIBI was 55.9%, 43.4%, 50.8% and 39.0%, respectively. In cases of single-gland disease, the sensitivity of MIBI/I, MRI, US and D-MIBI was 62.1%, 48.3%, 55.2% and 44.8%, respectively. In cases of multi-gland disease, the sensitivity of MIBI/I, MRI, US and D-MIBI was 50.0%, 37.5%, 46.7% and 36.7%, respectively. In cases of parathyroid adenoma, the sensitivity of MIBI/I, MRI, US and D-MIBI was 71.4%, 50.0%, 71.4% and 50.0%, respectively. In cases of parathyroid hyperplasia, the sensitivity of MIBI/I, MRI, US and D-MIBI was 55.2%, 42.3%, 50.0% and 39.7%, respectively. It is concluded that 99mTc-MIBI/123I subtraction is more useful than the delayed imaging of 99mTc-MIBI, MRI and US.     

The usefulness of Tc-99m tetrofosmin scintigraphy in the diagnosis and localization of hyperfunctioning parathyroid glands

PURPOSE: The aim of the work was to study the diagnostic value of Tc-99m tetrofosmin to localize anomalous parathyroid glands in patients with hyperparathyroid disease. METHODS: We studied 31 patients, 19 with primary and 12 with secondary hyperparathyroid disease. Five of these patients were renal graft recipients. All patients underwent surgery. Each patient was injected with 555 to 740 MBq (15 to 20 mCi) Tc-99m tetrofosmin. Subsequently, radionuclide images were acquired 15 and 120 minutes after injection using a low-energy, all-purpose, parallel-hole collimator. Pertechnetate thyroid scintigraphy was obtained in nine cases (24 to 48 h later) when the thyroid activity made it difficult to identify the parathyroid glands. RESULTS: All cases showed tracer uptake as early as 15 minutes after injection. In the group of patients with primary hyperparathyroid disease, 15 showed focal uptake in a parathyroid gland, and surgery revealed an adenoma in the same location. In one patient with hyperplasia, scintigraphy identified only two of four diseased glands. In the three remaining cases, scintigraphy showed focal uptake in the lower parathyroid gland, whereas at surgery the abnormal gland was located in the upper pole. In the secondary hyperparathyroidism group, seven patients showed diffuse tracer uptake in two or more glands, and histologic analysis confirmed hyperplasia in all of them. Five cases showed focal uptake, with three evaluated after surgery (uptake in the only remaining gland); one of them was a renal graft recipient, and the remaining patient had chronic renal failure and was receiving hemodialysis. CONCLUSIONS: Our results suggest that Tc-99m tetrofosmin may be a suitable tracer for preoperative detection and screening of anomalous parathyroid glands. The earlier images at 15 minutes were better than those at 120 minutes. Tc-99m tetrofosmin is cleared more slowly from the normal thyroid than is Tc-99m sestamibi, and both of these tracers may give better results than the old pertechnetate TI-201 subtraction technique.     

Complementary nature of radiotracer parathyroid imaging and intraoperative parathyroid hormone assays in the surgical management of primary hyperparathyroid disease: case report and review

PURPOSE: This article illustrates the complementary nature of preoperative radionuclide parathyroid imaging and intraoperative rapid parathyroid hormone (PTH) assays in primary hyperparathyroid disease. The authors review the literature on these procedures and compare this protocol and its cost-effectiveness with those of the classic four-gland exploration. MATERIALS AND METHODS: Preoperative parathyroid imaging with Tc-99m MIBI and intraoperative rapid PTH assays were performed at the time of neck exploration. RESULTS: One of two parathyroid adenomas seen on radionuclide images would have been missed if the authors had relied solely on the initial decrease in PTH assay value to a normal level. CONCLUSIONS: Tc-99m MIBI imaging and intraoperative rapid PTH assays are complementary; when used together, they lessen the likelihood that abnormal parathyroid glands will be overlooked. This experience and that of others suggest these combined procedures are cost-effective.     

Clinical role of 99mTcO4/MIBI scan, ultrasound and intra-operative gamma probe in the performance of unilateral and minimally invasive surgery in primary hyperparathyroidism

The main purposes of this study were: (a) to investigate the efficacy of an imaging protocol based on the combination of 99mTcO4/MIBI scintigraphy and neck ultrasound (US) in selecting patients with primary hyperparathyroidism (HPT) for unilateral neck exploration, and (b) to help define the role of the intraoperative MIBI gamma probe (IMGP) technique in the performance of minimally invasive radio-guided surgery (MIRS). One hundred and forty-three consecutive patients with primary HPT were enrolled in the study. We used a modified 99mTcO4/MIBI scintigraphic procedure which included the oral administration of potassium perchlorate to cause rapid 99mTcO4 washout from the thyroid tissue, thereby permitting the acquisition of high-quality early MIBI images. A single-photon emission tomography (SPET) acquisition was also obtained in 21 patients, of whom seven had an enlarged parathyroid gland (EPG) in the mediastinum at planar scintigraphy and 14 had discordant scan/US findings for the presence of a cervical EPG. Neck US was performed in the same session as scintigraphy using a small-parts, high-resolution 10-MHz transducer. All patients were then operated on by the same surgical team. Quick PTH assay (QPTH) was used to measure PTH intraoperatively to confirm successful parathyroidectomy. In patients with scan/US evidence of a solitary EPG and with a normal thyroid gland, limited, unilateral neck surgery or, more recently, MIRS was planned (n=91). In patients with scan/US evidence of multiglandular disease (MGD) (n=21) or concomitant nodular goitre (n=24) or in patients with a negative scan/US evaluation (n=7), extensive bilateral neck exploration was planned (n=52). In 87 of the 91 patients (95.6%) in whom preoperative imaging indicated the presence of a solitary EPG and a normal thyroid gland, a single parathyroid adenoma was found at surgery, and these patients were treated by unilateral neck exploration or MIRS. In the remaining four patients of this group, conversion to bilateral neck exploration was required because parathyroid carcinoma (n=3) or MGD (n=1) was diagnosed at operation. In some cases SPET was helpful in better localising the EPG. In particular, in 5 of the 21 patients evaluated, SPET localised an EPG deep in the neck or mediastinum and at surgery a parathyroid adenoma was found in the paratracheal or para-oesophageal space. In 43 of the 46 patients (93.5%) who were candidates for MIRS, the IMGP technique allowed parathyroidectomy to be performed through a small, 2- to 2.5-cm skin incision with a short duration of intervention (mean 34 min). We conclude that: (a) The integrated scan/US imaging protocol that we used appears to be accurate in selecting patients with primary HPT for unilateral neck exploration. (b) In our series the most prevalent cause of bilateral neck exploration was the co-existence of a nodular goitre; thus accurate preoperative evaluation of the thyroid gland by dual-tracer scintigraphy and US imaging is strongly recommended in all patients with HPT. (c) SPET can provide the surgeon with useful information when an EPG is located deep in the neck or mediastinum. (d) IMGP appears to be a useful intraoperative device in HPT patients with solitary parathyroid adenomas and a normal thyroid gland, since it permits minimally invasive and time-saving surgery.     

Determinant role of Tc-99m MIBI SPECT in the localization of a retrotracheal parathyroid adenoma successfully treated by radioguided surgery

PURPOSE: The authors' aim was to evaluate the role of MIBI SPECT acquired just after planar pertechnetate-MIBI (TcO(4)-MIBI) subtraction scintigraphy in planning radioguided surgery in a patient with persistent primary hyperparathyroidism after initial surgery performed to treat a retrotracheal parathyroid adenoma (PA). METHODS: A 73-year-old man with persistent primary hyperparathyroidism after a previous left parathyroidectomy and left thyroid lobectomy is described. The patient was examined in our center in a single-day preoperative imaging protocol based on findings of planar TcO(4)-MIBI subtraction scintigraphy, MIBI SPECT, high-resolution neck ultrasound, and computed tomography. RESULTS: Neck ultrasound did not reveal enlarged parathyroid glands. Findings of a neck-chest computed tomographic scan were also inconclusive. Instead, planar scintigraphy clearly depicted a single focus of MIBI uptake over the thyroid gland in a median position. The SPECT examination precisely localized a PA in the retrotracheal space. The day after imaging, the patient underwent unilateral left cervical surgical exploration. A 16 x 21 mm PA was easily detected using the gamma probe technique after injection of a low dose of 37 MBq (1 mCi) Tc-99m MIBI, and the PA was rapidly removed with limited surgical trauma. Rapid serum PTH and calcium levels normalized after intervention and remained in the normal range during subsequent follow-up. CONCLUSIONS: The current data indicate the importance of preoperative imaging with MIBI scintigraphy in patients with primary hyperparathyroidism and strongly support the utility of MIBI SPECT acquisition in PAs located deep in the neck and in ectopic sites. Furthermore, the gamma probe can help the surgeon to detect the PA during surgery and to minimize the surgical trauma in patients who have had previous thyroid or parathyroid surgery.     

Technetium-99m tetrofosmin for parathyroid scintigraphy: a direct comparison with (99m)Tc-MIBI, (201)Tl, MRI and US.

The aim of this study was to evaluate the efficacy and role of technetium-99m tetrofosmin for the detection of abnormal parathyroid glands to be referred for surgical treatment. Twenty-eight consecutive patients, including 25 primary and 3 secondary cases of hyperparathyroidism, were evaluated. (99m)Tc-tetrofosmin/(99m)Tc-pertechnetate subtraction scintigraphy (TF/Tc) was performed on all patients, and the results were directly compared with those of (99m)Tc-methoxyisobutylisonitrile (MIBI)/(99m)Tc-pertechnetate subtraction scintigraphy (MIBI/Tc), (201)Tl/(99m)Tc-pertechnetate subtraction scintigraphy (Tl/Tc), magnetic resonance imaging (MRI) and ultrasonography (US). In cases of single-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 63.2%, 68.4%, 57.9%, 55.6% and 63.2%, respectively. In cases of multi-gland disease, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 41.7%, 41.7%, 37.5%, 58.3% and 54.2%, respectively. In cases of parathyroid adenoma, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 68.8%, 75.0%, 68.8%, 62.5% and 75.0%, respectively. In cases of parathyroid hyperplasia, the sensitivities of TF/Tc, MIBI/Tc, Tl/Tc, MRI and US were 40.7%, 40.7%, 33.3%, 53.8% and 48.1%, respectively. It is concluded that, for the detection of abnormal parathyroid glands, (99m)Tc-tetrofosmin is as useful as (99m)Tc-MIBI and is more useful than (201)Tl.     

Preoperative parathyroid gland localization with technetium-99m sestamibi in secondary hyperparathyroidism

Technetium-99m sestamibi scintigraphy has become a valuable tool in locating parathyroid glands in patients with primary hyperparathyroidism. The aim of this study was to evaluate its usefulness in secondary hyperparathyroidism. Twenty patients were injected intravenously with 740 MBq of ^99mTc-sestamibi and images were obtained at 15 min and 2 h post injection. All patients underwent parathyroid ultrasonography (US) as well as bilateral surgical neck exploration and 64 parathyroid glands were removed. US revealed at least one enlarged gland in 15/20 patients (75%), while ^99mTc-sestamibi scintigraphy showed focal areas of increased uptake in at least one gland in 17/20 patients (85%). When imaging results for all glands were evaluated according to surgical results, sensitivity was 54% for parathyroid scintigraphy and 41% for US, and specificity was 89% for both imaging techniques. There was a discrepancy between the two imaging modalities in 28 glands (35%). The mean surgical weight of US-positive glands (1492±1436 mg) was significantly higher than that of US-negative glands (775±703 mg) (P<0.05). However, there were no significant differences in weight between sestamibi-positive and sestamibi-negative glands. When only sestamibi-positive glands were considered, a positive correlation between uptake and weight was found (r=0.4, P<0.05). In conclusion, parathyroid US and ^99mTc-sestamibi scintigraphy are complementary imaging techniques in the preoperative localization of abnormal parathyroid glands in patients with secondary hyperparathyroidism. The limited sensitivity of the techniques means that patients will still require bilateral neck exploration; therefore routine preoperative parathyroid scanning in renal patients is not justified. Received 1 June and in revised form 6 August 1997     

Preoperative evaluation of hyperparathyroidism: the role of dual-phase parathyroid scintigraphy and ultrasound imaging

Objective The aim of this study was to evaluate the efficacy of dual-phase 99mTc-methoxyisobutylnitrile (MIBI) parathyroid scintigraphy (PS) and ultrasound (US) in primary (pHPT) and secondary (sHPT) hyperparathyroidism. Methods A total of 69 patients (mean age 47 ± 16; age range 14–79 years), including 19 patients with sHPT were enrolled in this study. Preoperative serum intact parathyroid hormone (iPTH) levels, calcium (Ca), phosphate (P), alkaline phosphatase, and 24-h urinary-free Ca measurements were obtained. Concomitant thyroid pathology was also recorded. Results Histopathology revealed 30 solitary adenomas and 71 hyperplastic glands in 55 patients. The remaining patients’ histopathology revealed normal parathyroid, thyroid, or lymph nodes. The sensitivities of MIBI and US in pHPT were 70% and 60%, respectively. It was 60% for both procedures in sHPT. The overall sensitivity of combined US + MIBI in pHPT and sHPT was 81% and 71%, respectively. The overall specificity of MIBI and US was 87% and 91%; positive predictive value (PPV) was 94% and 92%, respectively. MIBI and US identified the parathyroid pathology in 92% and 85% of patients in the non-concomitant thyroid disease group, and in 53% and 47% of patients in the concomitant thyroid disease group, respectively. The weight of the gland between primary and secondary hyperparathyroidism did not reveal a significant difference (P = 0.4). Significant differences were found with respect to age, PTH, Ca, and P levels between the pHPT and sHPT (P < 0.001). Intact PTH levels showed significant differences between MIBI positive and negative patients (P = 0.013), and also US positive and negative patients (P = 0.012). A significant negative correlation was found between iPTH and Ca at sHPT (P < 0.001). Conclusions The concomitancy of thyroid disease greatly influences scintigraphic and ultrasonographic detection of parathyroid pathology in pHPT and sHPT. The combination of MIBI and US appears promising for localizing parathyroid pathology in patients with both primary and secondary hyperparathyroidism. The concordance rate is high together with a lower chance of missing concomitant thyroid pathology, which might alter the surgical approach.     

Clinical role of 99mTcO4/MIBI scan, ultrasound and intra-operative gamma probe in the performance of unilateral and minimally invasive surgery in primary hyperparathyroidism

The main purposes of this study were: (a) to investigate the efficacy of an imaging protocol based on the combination of ^99mTcO₄/MIBI scintigraphy and neck ultrasound (US) in selecting patients with primary hyperparathyroidism (HPT) for unilateral neck exploration, and (b) to help define the role of the intraoperative MIBI gamma probe (IMGP) technique in the performance of minimally invasive radio-guided surgery (MIRS). One hundred and forty-three consecutive patients with primary HPT were enrolled in the study. We used a modified ^99mTcO₄/MIBI scintigraphic procedure which included the oral administration of potassium perchlorate to cause rapid ^99mTcO₄ washout from the thyroid tissue, thereby permitting the acquisition of high-quality early MIBI images. A single-photon emission tomography (SPET) acquisition was also obtained in 21 patients, of whom seven had an enlarged parathyroid gland (EPG) in the mediastinum at planar scintigraphy and 14 had discordant scan/US findings for the presence of a cervical EPG. Neck US was performed in the same session as scintigraphy using a small-parts, high-resolution 10-MHz transducer. All patients were then operated on by the same surgical team. Quick PTH assay (QPTH) was used to measure PTH intraoperatively to confirm successful parathyroidectomy. In patients with scan/US evidence of a solitary EPG and with a normal thyroid gland, limited, unilateral neck surgery or, more recently, MIRS was planned (n=91). In patients with scan/US evidence of multiglandular disease (MGD) (n=21) or concomitant nodular goitre (n=24) or in patients with a negative scan/US evaluation (n=7), extensive bilateral neck exploration was planned (n=52). In 87 of the 91 patients (95.6%) in whom preoperative imaging indicated the presence of a solitary EPG and a normal thyroid gland, a single parathyroid adenoma was found at surgery, and these patients were treated by unilateral neck exploration or MIRS. In the remaining four patients of this group, conversion to bilateral neck exploration was required because parathyroid carcinoma (n=3) or MGD (n=1) was diagnosed at operation. In some cases SPET was helpful in better localising the EPG. In particular, in 5 of the 21 patients evaluated, SPET localised an EPG deep in the neck or mediastinum and at surgery a parathyroid adenoma was found in the paratracheal or para-oesophageal space. In 43 of the 46 patients (93.5%) who were candidates for MIRS, the IMGP technique allowed parathyroidectomy to be performed through a small, 2- to 2.5-cm skin incision with a short duration of intervention (mean 34 min). We conclude that: (a) The integrated scan/US imaging protocol that we used appears to be accurate in selecting patients with primary HPT for unilateral neck exploration. (b) In our series the most prevalent cause of bilateral neck exploration was the co-existence of a nodular goitre; thus accurate preoperative evaluation of the thyroid gland by dual-tracer scintigraphy and US imaging is strongly recommended in all patients with HPT. (c) SPET can provide the surgeon with useful information when an EPG is located deep in the neck or mediastinum. (d) IMGP appears to be a useful intraoperative device in HPT patients with solitary parathyroid adenomas and a normal thyroid gland, since it permits minimally invasive and time-saving surgery.     

Hyperparathyroidism: A comparison of sestamibi scintigraphy,mri, and ultrasonography

For patients with persistent or recurrent hyperpara-thyroldism, parathyroid imaging is indicated to confirm the presence of abnormal parathyroid gland(s) and identify their location. These imaging techniques are being modified constantly and newer methods have been developed. Sestamibi scintigraphy, MRI and sonography were compared in 23 patients with persistent or recurrent hyperparathyroidism. Preoperative 99m-Technetium Sestamibi (MIBI), MRI and ultraaono-graphic (US) studies of 23 patients with 25 histopatho-logically confirmed abnormal parathyroid glands were compared, using independent prospective interpretations. All patients had been operated upon previously for hyperparthytroidism. Accuracy of various combinations of MRI. MIBI, and US also were calculated. The results are shown for all abnormal glands (n = 25): sensitivities and accuracies were 88 and 84% for MRI. 80 and 80% for MIBI. and 58 and 44% for US. For only parathyroid adenomas (n = 18). sensitivities and accuracies were 89 and 89% for MRI, 94 and 94% for MIBI. and 58 and 39% for US. Finally, for parathyroid hyperplasla (n = 7 glands in five patients), sensitivities and accuracies were 83 and 71% for MRI. 43 and 43% for MIBI, and 57 and 57% for US. Either MIBI or MRI results were significantly better for detecting abnormal parathyroid glands than US (P <0.01), but MRI and MIBI were not statistically different. Combining MRI and MIBI produced a combined accuracy of 92%, whereas combining either of these tests with US did not improve on the accuracy of either test alone. In conclusion, for patients with persistent or recurrent hyperparathyroidism, MRI and MIBI are equally accurate for detecting abnormal parathyroid glands, and the combination of both tests may be more accurate than either test alone.     

SPECT/CT双时相联合减影技术诊断甲状旁腺功能亢进症的增益价值

目的探讨在99Tcm-MIBI双时相平面显像的基础上联合减影平面显像及SPECT/CT融合显像对甲状旁腺功能亢进症（以下简称甲旁亢）患者术前诊断的增益价值。方法2015年3月至2016年3月序贯纳入本院甲旁亢患者28例。所有患者行放射性核素显像前1~2周检测血清甲状腺旁腺激素（PTH）及血钙值。静脉注射99TcmO₄-40~60 MBq后行甲状腺99TcmO₄-显像;待采集结束后,再次静脉注射99Tcm-MIBI 600 MBq,行早期99Tcm-MIBI平面显像,后行SPECT/CT融合显像。在行99Tcm-MIBI延迟平面显像后,获得减影平面显像。以病理诊断结果为金标准,计算各显像技术的诊断效能。显像技术检出病灶数据的比较采用配对卡方检验,其他数值型变量采用Wilcoxon秩和检验。结果原发性和继发性甲旁亢患者术前检测PTH水平分别为（102.4±88.8）、（98.2±53.6）pmol/L,血钙水平分别为（2.9±0.3）、（1.9±0.2）mmol/L。28例甲旁亢患者共发现可疑性结节55处,其中40处甲旁亢病灶,15处非甲旁亢病灶。双时相检出19处病灶和2处阳性浓聚灶,其灵敏度为47.5%（19/40）。在双时相诊断甲旁亢病灶为阴性结果的患者中,减影相检出其他5处病灶,提高了病灶检出的灵敏度（60.0%）,差异有统计学意义（χ2=2.716,P=0.125）。SPECT/CT融合显像检出甲旁亢病灶26处,将双时相和减影相联合分析,检出甲旁亢病灶25处、非甲旁亢病灶4处;将双时相联合SPECT/CT融合显像分析,检出甲旁亢病灶26处、非甲旁亢病灶1处。减影相联合SPECT/CT融合显像与全部联合显像诊断效能相同,检出甲旁亢病灶27处、非甲旁亢病灶1处,其灵敏度和特异度较双时相（67.5% vs.47.5%和93.3% vs.86.7%）提高,差异均有统计学意义（χ2=6.635,P=0.02;χ2=4.432,P=0.04）。结论甲旁亢患者在行常规双时相平面显像的基础上联合减影平面显像及SPECT/CT融合显像,较单纯行双时相平面显像可以提高患者病灶的检出率。     

Tc-99m MIBI parathyroid scintigraphy and intact parathyroid hormone levels in hyperparathyroidism

Tc-99m MIBI has been widely used to evaluate hyperparathyroidism based on increased tracer uptake in hyperfunctioning parathyroid tissue. The functional status measurement of parathyroid glands with intact parathyroid hormone (iPTH) levels is also one of the most important diagnostic studies in this disorder. The aim of the current study was to assess the relation between MIBI imaging and iPTH levels. The authors retrospectively reviewed the records of patients with hyperparathyroidism who were referred to their department for Tc-99m MIBI scintigraphy. Sixty-five patients (24 primary and 41 secondary hyperparathyroidism) were included. The iPTH levels ranged from 66.06 to 2,836 pg/ml (normal, 10 to 55 pg/ml). Forty-two patients were MIBI positive and 23 were negative. The iPTH level in the MIBI-positive group was significantly greater than in the negative group in the primary (548 +/- 478 versus 124 +/- 45; = 0.002), secondary (1,155 +/- 692 versus 501 +/- 352; < 0.001), and overall (909 +/- 678 versus 386 +/- 341; < 0.001) groups. For the primary hyperparathyroidism group, 17 of the 24 patients were MIBI positive (71%). When iPTH levels exceeded 200 pg/ml (100%), the diagnostic sensitivity reached 100%. For the secondary hyperparathyroidism group, 25 of 41 patients (61%) were MIBI positive; 24 of 38 patients (63%) had an iPTH level greater than 200 pg/ml, 21 of 27 patients (78%) had an iPTH level greater than 500 pg/ml, and 11 of 12 patients (92%) had an iPTH value greater than 1,000 pg/ml. Tc-99m MIBI parathyroid scintigraphy showed a good correlation with iPTH level for both primary and secondary hyperparathyroidism. Visualization of hyperfunctioning parathyroid glands on Tc-99m MIBI parathyroid scintigraphy was more likely with a higher serum iPTH level in a dose-dependent manner.     

Comparison and histopathological correlation of three parathyroid imaging methods in a population with a high prevalence of concomitant thyroid diseases

The aim of this prospective study was to evaluate the diagnostic utility of a technetium-99m sestamibi dual-phase protocol enhanced by single-photon emission tomography (SPET) and semiquantitative analysis in comparison to established preoperative staging procedures in patients with primary hyperparathyroidism. Twenty-eight (50%) out of 56 patients had superimposed thyroid disease, and 12 patients had previously undergone neck surgery. Visual and semiquantitative analysis of planar^99mTc-sestamibi dual-phase imaging, SPET of the delayed phase, ultrasonography, and thallium-201 chloride-technetium-99m pertechnetate subtraction scintigraphy was further correlated with the histopathological examination of the surgical specimens.^99mTc-sestamibi dual-phase imaging achieved the highest sensitivity for side localization and precise localization compared with²⁰¹Tl-^99mTc subtraction scintigraphy and ultrasonography, but the differences reached statistical significance only in comparison to ultrasonography. Semiquantitative analysis did not enhance sensitivity. Adenoma detection by^99mTc-sestamibi dual-phase imaging was only correlated to serum calcium levels and osteocalcin, not to cell density or oxyphil cell count (SPET yielded additional information for the exact topographical localization of the parathyroid tumour in 22 (39%) patients with superimposed thyroid disease or previous neck surgery but did not enhance the overall detection rate.     

Incremental diagnostic value of preoperative 99mTc-MIBI SPECT in patients with a parathyroid adenoma.

The purpose of this prospective study was to evaluate the diagnostic value of early parathyroid SPECT combined with quantitative analysis as compared with planar imaging in patients undergoing minimally invasive radioguided surgery. METHODS: A total of 52 consecutive patients with primary hyperparathyroidism underwent planar and SPECT parathyroid scintigraphy 2-5 d before surgery. Each patient had a single-tracer dual-phase technique using (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) and a double-tracer subtraction technique using a delayed (99m)Tc-pertechnetate scan. Immediately after the first (99m)Tc-MIBI planar image, a SPECT study was acquired. Before radioguided parathyroidectomy, each patient was reinjected with (99m)Tc-MIBI. Serum calcium levels were available for all patents before surgery and at 8 and 24 h after surgery. Serum parathyroid hormone (PTH) levels were also available for all patients. Quantitative analysis was performed using the average count ratio of parathyroid to left thyroid lobe, right thyroid lobe, and maximum thyroid activity. All patients had histopathologic examination of the removed glands. RESULTS: The average time for radioguided surgery was 30 min (range, 20-40 min). Postsurgical calcium levels correlated significantly with the adenoma weight (r = 0.5; P = 0.016). Combined planar scintigraphy correctly identified 41 adenomas (79%). SPECT increased the sensitivity to 96%. SPECT was superior to planar imaging in 9 patients, mainly in patients with ectopic adenomas or with multinodular goiters. Gland size did not affect significantly the detectability of SPECT. (99m)Tc-MIBI retention was noted in only 31 adenomas (60%). The average uptake ratios of parathyroid counts to the left lobe, right lobe, and maximum thyroid activity were 1.20 +/- 0.42, 1.29 +/- 0.45, and 0.84 +/- 0.35, respectively. The latter ratio was significantly correlated with PTH levels before surgery (r = 0.408; P = 0.04). CONCLUSION: Our data indicate that early preoperative SPECT in patients with primary hyperparathyroidism is essential for accurate localization of parathyroid adenomas and for the selection of patients who are candidates for minimally invasive radioguided surgery. Planar parathyroid imaging is less sensitive compared with SPECT, and washout kinetics of (99m)Tc-MIBI are unreliable in the dual-phase technique. Patients with higher presurgical PTH levels may especially benefit from radioguided surgery.