technetium-tc-99m-tetrofosmin and Hyperparathyroidism--Secondary

Considered rare disease in the past, primary hyperparathyroidism (PHPT) has dramatically increased in incidence over the past thirty years with the introduction of routine calcium measurements; it is now approximately 42 per 100 000 persons. By far, the most common lesion found in patients with PHPT is the solitary parathyroid adenoma, occurring in 85%-90% of patients, while in the rest 10%- 15% primary hyperplasia of the parathyroid glands is present. Currently, the most widely used surgical approach is minimally invasive parathyroidectomy which is associated with less post-surgery complications and shorter operation time. To be successful this procedure needs to rely on a precise preoperative localization of the abnormal parathyroid glands, hence preoperative parathyroid imaging gained so large importance. The rationale for locating abnormal parathyroid tissue prior to surgery is that the glands can be notoriously unpredictable in their location. There is a general consensus that the best imaging procedure identifying abnormal parathyroid glands is the preoperative scintigraphy with 99mTc-sestamibi or 99mTc-tetrofosmin. It is characterized with high sensitivity and specificity exceeding those of ultrasound, CT or MRI. Combining scintigraphy with the other imaging techniques increases the precision for topic localization.

Topics: Humans; Hyperparathyroidism, Primary; Hyperparathyroidism, Secondary; Nuclear Medicine; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Positron Emission Tomography Computed Tomography; Technetium Tc 99m Sestamibi

Preoperative imaging has proved its use successful in the localization of solitary parathyroid adenomas in patients with suspected primary hyperparathyroidism. However, due to multiglandular disease at presentation patients with renal hyperparathyroidism need to be analyzed separately, making the usefulness of imaging techniques controversial. Recently, improved methods of functional imaging like parathyroid scan with 99mTc-sestamibi or positron emission tomography, especially when combined with computed tomography, can provide additional quantitative and qualitative information that has yet to be assessed. Nuclear medicine procedures could prove useful not only in preoperative diagnosis, but also in the selection of medical or surgical therapeutic alternatives in secondary hyperparathyroidism patients. There is evidence that 99mTc-sestamibi uptake in parathyroid hyperplasia or adenoma is related to biochemical markers of parathyroid function. We are only beginning to identify the factors involved in radiotracer uptake by parathyroid cells and how it can be modulated to obtain more accurate results. This review analyzes the current use of non-invasive imaging modalities in patients with secondary hyperparathyroidism, taking into account the latest trends in the field combining anatomic and functional modalities and the relevant factors linked to radiotracer uptake in abnormal hyperfunctioning parathyroid glands.

Topics: Calcium; Diagnostic Imaging; Humans; Hyperparathyroidism, Secondary; Hypocalcemia; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroidectomy; Positron-Emission Tomography; Preoperative Care; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Tissue Distribution; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Ultrasonography

We report the rare case of a recurrent hyperparathyroidism after total parathyreoidectomy due to multiple ectopic glands in a patient on long-term haemodialysis. In a today 47 years old man with membranoproliferative glomerulonephritis intermittent haemodialysis therapy was started in 1975. In 1982 an advanced secondary hyperparathyroidism with a parathormone (PTH) level > 500 pg/l was diagnosed; later on PTH concentration increased to 2,550 pg/ml. In 1987 total parathyroidectomy with parathyroid autograft into the left forearm was performed. After parathyroidectomy the PTH level fell to 150 pg/ml. In 1993 PTH concentration increased again to 1,750 pg/ml. There was no evidence for recurrent parathyroid glands in the neck or forearm. Therefore, we investigated the substernal region by 99mTc-tetrofosmin scintigraphy and magnetic resonance imaging. Both investigations showed evidence for two ectopic parathyroid glands in the anterior mediastinum. In June 1999 in an open thoracic surgical procedure only the greater parathyroid gland in the anterior mediastinum was isolated, but a second gland was detected in the posterior mediastinum. Both parathyroid glands were resected (histologically hyperplastic parathyroid gland tissue). After surgery the PTH level decreased to 340 pg/ml, but later on PTH increased again to > 1,000 pg/ml in January 2001. A control 99mTc-tetrofosmin scan showed evidence for a third ectopic parathyroid gland in the anterior mediastinum. Recurrent secondary hyperparathyroidism can rarely be caused by recurrent ectopic parathyroid glands in the mediastinum.

Topics: Choristoma; Humans; Hyperparathyroidism, Secondary; Magnetic Resonance Imaging; Male; Mediastinal Diseases; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Parathyroidectomy; Postoperative Complications; Recurrence; Renal Dialysis; Reoperation; Thoracotomy

Topics: Adult; Humans; Hyperparathyroidism, Secondary; Hyperplasia; Kidney Transplantation; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Radionuclide Imaging; Radiopharmaceuticals; Renal Insufficiency

The aim of the study was to quantitatively compare the scintigraphic images of the thyroid and abnormal parathyroid glands obtained with technetium-99m tetrofosmin and thallium-201 in patients with hyperparathyroidism. Forty-six patients with hyperparathyroidism underwent (201)Tl (74 MBq), (99m)Tc-pertechnetate (74 MBq) and (99m)Tc-tetrofosmin (555-740 MBq) scintigraphy in a single session. Image analysis included the computation of the thyroid/background ratio in the whole study population and the parathyroid/background ratio, parathyroid/thyroid ratio and diagnostic sensitivity in 17 patients who underwent parathyroid surgery. The pertechnetate subtraction technique was used. (201)Tl and (99m)Tc-tetrofosmin showed a similar thyroid/background ratio (1.79+/-0.41 and 1.81+/-0. 47, respectively, P=NS); however, (99m)Tc-tetrofosmin showed a higher parathyroid/background ratio than (201)Tl (2.06+/-0.54 vs 1. 79+/- 0.50, P=0.007). Despite the superior quality of (99m)Tc-tetrofosmin images, both tracers showed identical sensitivity in detecting enlarged parathyroid glands in patients with primary hyperparathyroidism (89%) and in those with secondary hyperparathyroidism (50%).

Topics: Adenoma; Female; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Male; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Parathyroid Neoplasms; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Sodium Pertechnetate Tc 99m; Thallium Radioisotopes; Thyroid Gland

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.. 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.. 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.. 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.

Topics: Adenoma; Adult; Aged; Evaluation Studies as Topic; Female; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Hyperplasia; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Parathyroid Neoplasms; Radionuclide Imaging; Radiopharmaceuticals; Renal Dialysis; Sodium Pertechnetate Tc 99m; Subtraction Technique; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Thyroid Gland; Time Factors

The aim of the work was to study the diagnostic value of 99mTc-tetrofosmin to localize anomalous parathyroid glands in patients with hyperparathyroidism.. We have studied 33 patients: 12 with primary and 21 with secondary hyperparathyroidism, 9 of them renal graft recipients. Sixteen patients underwent surgery, 12 with primary and 4 with secondary hyperparathyroidism. All patients were injected with 740 MBq of 99mTc-tetrofosmin. Subsequently at 15, 30 and 60 minutes images were acquired for 300 seconds using a pin-hole collimator. A pertechnetate thyroid scintigraphy was obtained in 7 cases (24-48 h later) when the thyroid activity made difficult the identification of parathyroid glands.. In the group of patients with primary hyperparathyroidism, all cases showed a focal uptake in lower right localization. In the secondary hyperparathyroidism group, 12 patients showed diffuse tracer uptake in two or more glands and histology confirmed hyperplasia in four of them. Seven cases showed a greater focal uptake in a gland: two of them were renal graft recipients and three were chronic renal failure cases in haemodyalisis, and two were evaluated postsurgery showing uptake in the remnant parathyroid gland. The two remaining patients had a normal scintigraphy and corresponded to two false negative cases. In conclusion, our results suggest that 99Tc-tetrofosmin may be used as a suitable tracer for preoperative detection and screening of anomalous parathyroid glands.

Topics: Adenoma; Adult; Aged; Aged, 80 and over; Female; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Hyperplasia; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Parathyroid Neoplasms; Postoperative Complications; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Thyroid Gland

The efficacy of 99mTc-tetrofosmin for the detection of parathyroid lesions was investigated prospectively in patients with hyperparathyroidism referred for surgical treatment.. Twenty-seven patients with primary and 18 with tertiary hyperparathyroidism were studied. Twelve patients had undergone one or more previous neck explorations. Static imaging with 201Tl was performed first, immediately followed by a 30-min 99mTc-tetrofosmin dynamic study. Delayed views of up to 3 hr postinjection were also obtained. Technetium-99m-pertechnetate was used for thyroid delineation. The tetrofosmin/99mTc-pertechnetate subtraction scan (TF/TC), the single-tracer washout technique and the thallium/technetium subtraction (TL/TC) were compared. Quantification of relative uptakes of tracers in the thyroid and abnormal parathyroids was accomplished by measuring activity within regions of interest. Kinetics of tetrofosmin in the thyroid and abnormal parathyroids were studied by evaluating the plots of the parathyroid to thyroid ratios against time as well as by calculation of the half-clearance times from the slow component of the time-activity curves.. The overall sensitivity, specificity and accuracy of TF/TC and TL/TC were 76%, 92% and 83% and 52%, 85% and 65%, respectively. The respective sensitivities were 87% and 70% for adenomas and 72% and 46% for hyperplasia. The parathyroid-to-thyroid activity ratios of tetrofosmin were significantly higher than those of thallium (p < 0.001). The tetrofosmin single-tracer washout study was less accurate than the subtraction technique (overall sensitivity and specificity, 70% and 69%, respectively). The washout properties of tetrofosmin in abnormal parathyroids were not substantially different from those in the thyroid, with a few exceptions (p = 0.4). No correlation of half-clearance times with parathyroid size, degree of early uptake, parathyroid hormone levels or histology could be established. Comparing adenomas to hyperplasia in respect to tetrofosmin retention, a statistically significant difference was observed (p = 0.005).. Technetium-99m-tetrofosmin is suitable for parathyroid imaging. The kinetic properties of this agent in parathyroid and thyroid tissues do not warrant differential washout protocols. The diagnostic impact of the observed difference in tetrofosmin kinetics between parathyroid adenomas and hyperplasia requires further investigation.

Topics: Adenoma; Female; Humans; Hyperparathyroidism, Secondary; Hyperplasia; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Parathyroid Neoplasms; Prospective Studies; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Sodium Pertechnetate Tc 99m; Subtraction Technique; Thallium Radioisotopes; Thyroid Gland; Time Factors

Preoperative localization of hyperactive parathyroid glands is useful to minimize operative time and reduce patient morbidity. This investigation compared the sensitivity of radionuclide imaging with 99mTc tetrofosmin with that of ultrasonography and magnetic resonance (MR) imaging in patients with hyperparathyroidism.. Twenty-six patients with primary (n = 7) or secondary (n = 19) hyperparathyroidism were imaged with 99mTc tetrofosmin, ultrasound and MR imaging of the neck and thorax to localize the lesions. The presence of hyperparathyroidism was identified by an intact parathyroid hormone in vitro assay. The parathyroid/normal thyroid tissue activity ratio was calculated for all patients with evidence of an abnormality on tetrofosmin images. Pathological findings were compared with the results of imaging in 18 of the 26 patients who underwent parathyroidectomy.. Technetium-99m tetrofosmin scans demonstrated focal uptake in 46 glands of 26 patients. The uptake was categorized as slight in 78.3% (36/46) and intense (parathyroid/normal thyroid tissue activity ratio, > 1.4) in 21.7% (10/46). Ultrasonography and MR imaging identified 44 and 47 glands, respectively, in these patients. Eleven of the 18 patients who underwent parathyroidectomy within 1 mo after tetrofosmin imaging had hyperplastic glands, while 7 had parathyroid adenomas. Tetrofosmin imaging successfully localized 7 of 7 (100%) adenomas and 27 of 37 (73.0%) hyperplastic glands. The sensitivities of each technique for localizing abnormal parathyroid glands were 77.3% (34/44) for tetrofosmin imaging: 68.2% (20/44) for ultrasonography: and 68.2% (30/44) for MR imaging. Technetium-99m tetrofosmin uptake ratio in the 18 patients with surgical exploration was not proportional to several oxyphil cells.. Technetium-99m tetrofosmin parathyroid imaging may be useful for localizing abnormal glands in patients with primary and secondary hyperparathyroidism. The sensitivity of 99mTc tetrofosmin parathyroid imaging was high as compared to ultrasonography or MR imaging. The prolonged retention of tetrofosmin may not depend on the number of mitochondria-rich oxyphil cells.

Topics: Adenoma; Female; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Hyperplasia; Magnetic Resonance Imaging; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Glands; Parathyroid Neoplasms; Preoperative Care; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Ultrasonography

Topics: Adenoma; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Organophosphorus Compounds; Organotechnetium Compounds; Parathyroid Neoplasms; Radiopharmaceuticals; Sensitivity and Specificity; Subtraction Technique; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon