Localization In Primary Hyperparathyroidism Research Articles

Ultrasound for Localization in Primary Hyperparathyroidism

Objective: Minimally invasive surgery for primary hyperparathyroidism has gained significant popularity. Preoperative localization is required, with ultrasonography and sestamibi imaging being most commonly utilized. When both are obtained, frequently the same site is localized. It is unclear that 2 localization techniques are required in patients with hyperparathyroidism. Method: Prospectively collected data from the Midwest Head and Neck Cancer Consortium’s parathyroid protocol was retrospectively reviewed. The study included patients that had preoperative localization and subsequently underwent surgery. The localization studies were correlated to surgical findings. Results: Of the 96 patients, preoperative US, sestamibi, or both studies were obtained in 77, 88, and 71, respectively. Preoperative US and sestamibi localized an abnormality in 69% and 80%, respectively. In patients with localizing US, surgical findings were exactly as predicted in 75% and localized to the correct side in 84%. The accuracy of localization was similar for sestamibi imaging. In 8 patients with inaccurate US localization, the sestamibi detected an abnormal gland in only 50%. In patients with a nonlocalizing US, sestamibi was able to detect disease in 75%, with 2 being in the mediastinum. Conclusion: Given the lower cost of ultrasonography, it is an acceptable initial localization study for patients with primary hyperparathyroidism. In patients with nonlocalizing ultrasound, sestamibi imaging should be obtained. Frequently potential sites of disease will be identified, still allowing for a minimally invasive surgical approach.

Clinical implications of brown tumor uptake in whole-body 99mTc-sestamibi scans for primary hyperparathyroidism

Technetium-99m (Tc)-sestamibi is the current radionuclide of choice for parathyroid localization in primary hyperparathyroidism (PH). However, there are only sporadic reports about brown tumor visualization in whole-body Tc-sestamibi scans. This study aimed to systematically evaluate brown tumor uptake in whole-body Tc-sestamibi scans and in whole-body bone scans as well. Clinical factors were statistically analyzed for imaging outcome predictions. Forty-two patients with PH were recruited consecutively. A dual-tracer, dual-phase parathyroid imaging protocol was applied. A Tc-sestamibi whole-body scan was performed immediately after delayed phase acquisition. A Tc-methylene diphosphonate bone scan was performed on day 3. Parathormone (PTH), calcium, alkaline phosphatase (ALP), and parathyroid lesion volume were compared. The t-test, one-way analysis of variance, and receiver operating characteristic curves were performed for statistical analyses. Brown tumors showed Tc-sestamibi uptake in 10 cases, and Tc-methylene diphosphonate uptake in 17 cases. All parameters in double-scan positive cases were significantly higher than in double-scan negative cases; PTH and ALP were significantly higher in only bone scan positive cases than in double-scan negative cases. Data from receiver operating characteristic curves showed the order of PTH>ALP>Ca>parathyroid lesion volume for diagnostic accuracies of both positive Tc-sestamibi scans and positive bone scans. PTH showed the best positive predictive value and ALP showed the best negative predictive value. A Tc-sestamibi whole-body scan could be used to assess brown tumors in PH, although it may be less sensitive than a bone scan. PTH possessed the best diagnostic accuracy and predictive value for a positive imaging outcome. ALP was useful for negative imaging outcome prediction.

Fusion imaging for parathyroid localization in primary hyperparathyroidism

Primary hyperparathyroidism, most commonly due to a solitary parathyroid adenoma, has become an increasingly diagnosed condition and is one with great potential for cure following appropriate surgical intervention. Functional imaging with Tc-99m-based radiopharmaceuticals has contributed significantly to increased success in preoperative adenoma localization but the advent of fusion of this functional information with anatomical details obtained with computed tomographic imaging has yielded a potentially more powerful clinical tool and one that is particularly well suited to ectopic adenomas and cases of prior failed surgery. Aspects of this modality are discussed with reference to software- and hardware-based fusion techniques and evidence for efficacy. The allied technique of PET/computed tomography is also discussed.

Comparison of 923 Sestamibi Scans for Primary Hyperparathyroidism with Final Parathyroid Pathology

Introduction: Preoperative technetium Tc 99m Sestamibi has become the gold standard for localization in primary hyperparathyroidism treated by minimally invasive parathyroidectomy; however, no large cohort studies from a single institution have been published to prove this model is effective. The goal of this study was to quantify how well Sestamibi scans predict findings upon surgical exploration and compared to final pathology. Methods: All patients >16 years, diagnosed with hyperparathyroidism, who underwent a Sestamibi scan interpreted by a single radiologist from 6-1-07 to 5-30-08, were abstracted from hospital databases.

Sestamibi Scans Are Not All Created Equally

The sensitivity of sestamibi scanning techniques used for preoperative localization in primary hyperparathyroidism is a function of the parameters of image acquisition and processing. Criterion standard vs optimized technique. Tertiary referral center. One hundred forty-eight consecutive patients with primary hyperthyroidism were analyzed. Under the initial protocol, 97 patients underwent a preexisting standard sestamibi--single-photon emission computed tomographic scan and surgical exploration. The scanning technique was modified and in the revised protocol, 51 patients underwent imaging and surgical exploration. Image acquisition and processing revisions as follows: patient positioning standardized, collimator resolution adjusted, radioactive tracer delay extended, visualization field broadened, data extraction refined, and image processing filter modified. concordance among the scan and operative localization, lateralization, and cure rate. Initial protocol: 97 patients underwent surgery for primary hyperthyroidism with the initial sestamibi design. Eighty-one patients (83%) had a positive result, that is, at least 1 gland was identified; 77 patients (79%) had correct lateralization; and 49 patients (52%) had precise localization. Revised protocol: 51 patients underwent imaging under the optimized protocol. Forty-nine patients (96) had a positive result; 47 patients (92%) had correct lateralization; and 36 patients (70%) had precise localization. These improvements were significant, with P<.05 for localization and P<.01 for lateralization. Cure rates were 96% in both groups, confirmed by laboratory and pathologic findings. Sestamibi optimization in primary hyperparathyroidism can improve scan sensitivity. This may permit a focused minimally invasive operation.

Computed axial tomography–MIBI image fusion for preoperative localization in primary hyperparathyroidism

Background An imaging-guided unilateral surgical approach in patients with primary hyperparathyroidism (HPTH) requires reliable preoperative localization procedures. Using present imaging techniques, 60% to 80% of patients with primary HPTH can be treated successfully with limited surgery. Thus, further improvement of diagnostic accuracy is required. Computed axial tomography (CAT)–MIBI image fusion was introduced as a new technique for localizing enlarged parathyroid glands. We describe the new method and present its first results. Methods Six consecutive patients with primary HPTH underwent CAT–MIBI image fusion for preoperative parathyroid localization. CAT and technetium-99m–sestamibi scan were performed separately. The patient's head and neck were fixed with the noninvasive Vogele-Bale-Hohner Head Holder (VBH HeadFIX; Medical Intelligence, Schwabmünchen, Germany) and the BodyFIX (Medical Intelligence) vacuum cushion. Radiographic and scintigraphic markers were mounted at the head holder and the patient. CAT and MIBI images were fused by overlaying radiographic markers using a commercial software and workstation. Results In 5 patients, localization and dimension of the solitary adenomas were exactly predicted. In 1 patient with multiglandular disease (3 enlarged glands), CAT–MIBI image fusion was not able to predict multiple gland involvement. However, in a retrospective analysis of the localization study, the other two enlarged parathyroid glands could be correctly identified regarding their site and size. Conclusions First results of CAT–MIBI image fusion are promising. The new technique provides a higher image resolution and better delimitation of enlarged parathyroid glands and adjacent anatomic structures than conventional scintigraphic methods.

原発性上皮小体機能こう進症例の術前部位診断

原発性上皮小体機能こう進症例の術前部位診断

Preoperative imaging for parathyroid localization in primary hyperparathyroidism.

We retrospectively studied the results of diagnostic imaging using 3 different modalities to determine their usefulness for preoperative localization of the parathyroid, and whether accurate preoperative localization information could be used to modify the surgical approach for parathyroidectomy in patients with primary hyperparathyroidism. Images of 37 parathyroid adenomas or hyperplasias in 35 patients with primary hyperparathyroidism were obtained using ultrasonography, computed tomography, and subtraction scintigraphy (using thallium 201 [thallous chloride] and either iodine 123 or technetium 99m pertechnetate [99mTcO4-]). Approximately three fourths of the adenomas or hyperplasias were successfully identified by ultrasound (76.7%) and computed tomography (76.4%), even when the weight of the tumor was less than 500 mg. However, subtraction scintigraphy was of limited use (61.3% successfully identified). A combination of these modalities gave excellent results for detecting adenomas and hyperplasias, leading to an accurate prediction rate of 96.0%. We conclude that using the combination of these 3 imaging modalities is very useful for the detection of parathyroid adenomas and hyperplasias, and that with such accurate localization information, the unilateral approach alone, or even simple excision of the parathyroid tumors might be feasible, enabling less invasive surgical treatment.

Sestamibi scan for preoperative localization in primary hyperparathyroidism.

Various invasive and noninvasive localizing tests are available for the evaluation of primary hyperparathyroidism. The surgical success in primary intervention exceeds 90% without localization studies. However, localization tests are absolutely essential for re-exploration and in certain select circumstances, even in primary exploration. The traditional noninvasive localization studies include the sonogram, thallium-technetium scan, computed tomography (CT) scan, and magnetic resonance imaging (MRI). The purpose of this report is to review our recent experience with sestamibi scan. The sestamibi scan appears to be the most sensitive and accurate noninvasive test available today. Technetium 99m sestamibi has recently been used for parathyroid localization, in conjunction with iodine123 subtraction. We have evaluated 24 patients with suspected primary hyperparathyroidism to study the role of technetium 99m sestamibi scan. Tc-sestamibi was used either with or without iodine123 for subtraction of thyroid activity. None of these patients had renal failure or secondary hyperparathyroidism. Of 24 patients, the parathyroid adenoma was localized by scintigraphy in 19 patients. Twenty patients underwent surgical exploration. In 17 patients there was a complete correlation between the imaging study and the operative findings (positive predictive value, 89%). There were no false positives in this series. The interpretation of the parathyroid images was relatively easy; however, the depth of the adenoma could not be predicted, based on the scan alone. The largest adenoma weighed 2.7 g, the smallest, 700 mg. This newer radiopharmaceutical, technetium 99m sestamibi, appears to be quite useful and accurate in the preoperative localization of patients with primary hyperparathyroidism. Parathyroid enlargement can also be studied by sestamibi imaging alone if delayed imaging is performed.

The accuracy of parathyroid gland localization in primary hyperparathyroidism using sestamibi radionuclide imaging.

Primary hyperparathyroidism is a common condition due to either a parathyroid adenoma or, less commonly, parathyroid hyperplasia, whose treatment is essentially surgical. We have, therefore, assessed the accuracy of Tc-99m pertechnetate/Tc-99m sestamibi (methoxy-isobutyl isonitrile) imaging in the localization of adenomas and hyperplastic parathyroids. The clinical records of all patients who had Tc-99m pertechnetate/Tc-99m sestamibi imaging and parathyroid surgery at this hospital were reviewed. The technique used involves standard subtraction methodology with the addition of a novel change detection algorithm to optimize localization. Of 46 patients scanned in 48 patient episodes, 36 patients had adenomas; 28 (78%) were accurately localized to the correct quadrant, and 4 were correctly lateralized. Two patients with parathyroid carcinomas had their metastases correctly localized. Thus, in 34 of 38 (89.5%) of the scans, adenomas or carcinomas were able to be anatomically localized. Six patients presented with hyperplasia; 5 were diagnosed by sestamibi scans, and 3 of these accurately localized all hyperplastic glands. Four additional patients had known hyperplasia, of which 2 were rendered normocalcemic after removal of their sestamibi-positive glands; the other 2 had small second glands detected only at surgery. In patients with unknown pathology, imaging suggested that 6 patients had hyperplasia; this was correct in 5 cases (83%). Nine of the 12 scans in patients who had had previous parathyroid surgery accurately localized the tumors, 7 in the neck and 2 outside. We suggest that sestamibi imaging can help to distinguish hyperplasia from adenomatous disease; when imaging is required, we recommend it as the imaging modality of choice in all patients with primary hyperparathyroidism, especially in reoperated patients.

Parathyroid localization in primary hyperparathyroidism

原発性副甲状腺機能亢進症24例を対象に,種々の非侵襲的部位診断法の有用性について検討した.腫瘍の触診可能例は, 2.0g以上の症例に限られた.超音波検査と201Tl・99mTc併用シンチ検査では, 0.5g以上の副甲状腺腫のほぼ全例を,それ以下の例では,いずれも約半数ほどを検出しえた.またCT検査による検出率は,画像診断法のなかで最も低値を示した.なお甲状腺疾患を29%に合併しており,確定診断の際に注意を要した.

Parathyroid localization in primary hyperparathyroidism: double-tracer scintigraphy and venous sampling techniques combined. A first evaluation.

The authors report their first experience with two techniques for preoperative localization of hyperfunctioning parathyroid glands: double-tracer (99mTc-201Tl) scintigraphy and venous sampling from thyroid veins. Nineteen patients affected by primary hyperparathyroidism were examined by both methods and subsequently submitted to surgery. Scintigraphy showed a sensitivity of 77.3% while the positivity of sampling was 63.6%; with the two techniques combined a correct localization was obtained in 90.9% of all cases. The authors emphasize the usefulness of both methods combined for locating enlarged hyperfunctioning parathyroids.