Efficacy of preoperative dual-phase sestamibi scanning in hyperparathyroidism

PURPOSE: The objective of this article is to evaluate our experience with sestamibi scanning in patients with primary and secondary hyperparathyroidism. PATIENTS AND METHODS: A retrospective review of patients referred to the radiology department at the University of Kansas Medical Center for parathyroid studies between January 1, 1993, and August 1, 1998, was done. Patients included in the study were those who underwent both dual-phase technetium (Tc-99m) sestamibi scanning and subsequent parathyroidectomy at our institution (n = 34). Twenty-six patients had primary hyperparathyroidism and 8 patients had secondary hyperparathyroidism. Fifteen had previous history of neck exploration. RESULTS: Sensitivity of sestamibi scans in detection of all abnormal pathology in cases of primary hyperparathyroidism was 60% overall. Among the subset of adenoma cases, sensitivity was 82% (14/17). Among cases of primary parathyroid hyperplasia, no scan correctly localized all abnormal glands; however 60% (3/5) showed localization of at least one hyperplastic gland. Of the 2 patients with parathyroid carcinoma, in only one case was there evidence of sestamibi retention in the correct thyroid lobe. In patients with secondary hyperparathyroidism, sestamibi scanning was successful in identifying all hyperplastic tissue in only one case (sensitivity 13%). In 7 of the 8 cases of secondary hyperparathyroidism, the scan localized at least one hyperplastic gland. CONCLUSION: Sestamibi scanning is useful in the localization of abnormal pathology in cases of primary hyperparathyroidism, especially adenomas. In cases of hyperplasia, whether attributable to primary or secondary hyperparathyroidism, sestamibi imaging is less successful.     

Technetium Tc 99m sestamibi sensitivity in oxyphil cell-dominant parathyroid adenomas

OBJECTIVE: A subset of parathyroid adenomas contains a relative overabundance of oxyphil cells that are capable of greater technetium Tc 99m sestamibi tracer uptake and retention than other cell types. We examined whether the presence of oxyphil cells augments the sensitivity of technetium Tc 99m sestamibi preoperative localization and whether the histologic findings of a lesion could be predicted based on the adenoma mass and serum calcium and parathyroid hormone levels. DESIGN: Retrospective, single-blinded comparison of technetium Tc 99m sensitivity rates, lesion mass, and preoperative serum calcium and parathyroid hormone values of patients with chief and mixed cell-dominant adenomas and those with oxyphil-dominant parathyroid adenomas. SETTING: Tertiary care university hospital. PATIENTS: Sixty-three patients diagnosed as having a parathyroid adenoma. INTERVENTION: All patients underwent resection of a parathyroid adenoma following a preoperative technetium Tc 99m sestamibi localization study and serum calcium and parathyroid hormone level analysis. MAIN OUTCOME MEASURE: Technetium Tc 99m sensitivity rate. RESULTS: The overall technetium Tc 99m sestamibi sensitivity rate was 76.2%. The sensitivity within the chief and mixed cell-dominant (n = 52) and oxyphil cell-dominant groups (n = 11) were 71.2% and 100%, respectively (P = .04). There was no correlation between histologic findings of the lesion and its size or serum calcium and parathyroid hormone levels. CONCLUSIONS: Oxyphil cell predominance within an adenoma augments technetium Tc 99m sestamibi scan sensitivity in a statistically significant manner. The use of technetium Tc 99m sestamibi preoperative localization may therefore be differentially greater in patients with these types of lesions.     

Role of microvascular density in nonlocalizing parathyroid sestamibi scans

OBJECTIVES: Sestamibi scans for localization of abnormal parathyroid glands in patients with hyperparathyroidism are widely used at many institutions. Minimally invasive parathyroid surgery demands accurate preoperative localization imaging; however, nonlocalizing sestamibi scans occur in 15% of patients with primary hyperparathyroidism. It remains unknown why some sestamibi scans fail to localize. We hypothesize that an increase in microvascular density (MVD) within an adenoma will result in rapid tracer washout and a subsequent nonlocalizing scan. This study investigates the role of MVD in sestamibi localization. STUDY DESIGN: Retrospective chart review with immunohistochemical staining and data analysis. METHODS: Medical records of 83 patients who had a sestamibi scan for evaluation of primary hyperparathyroidism and underwent initial parathyroidectomy from 2000 to 2002 were retrospectively reviewed. Patients' age, sex, preoperative imaging results, operative procedure, gland weight, and histologic findings were collected. Immunohistochemistry was performed to assess MVD. RESULTS: Of the 75 preoperative sestamibi scans used, 51 patients had a localizing scan, and 24 were nonlocalizing. Localizing sestamibi scans for primary hyperparathyroidism demonstrated a sensitivity of 94% and specificity of 85%. By identifying multiglandular hyperplasia, nonlocalizing sestamibi scans produced a sensitivity of 83%. The localizing group had a greater percentage of solitary adenomas (94%) compared with the nonlocalizing group (15.6%) (P < .001). The mean gland weight for the nonlocalizing group was less than 398 g compared with the localizing groupweight of 1,113 g (P < .001). The mean MVD for localizing scan group was 229 vessels per high-power field,and the mean for the nonlocalizing scans was 213 vessels per high-power field (P = .2). CONCLUSIONS: MVD does not predict whether sestamibi scans are localizing or nonlocalizing.     

Parathyroid adenomas: is bilateral neck exploration necessary?

PURPOSE: The traditional surgical treatment for primary hyperparathyroidism is bilateral neck exploration with identification of all parathyroid glands. Multiple investigators who recommend initial unilateral neck exploration based on more advanced localization studies have recently challenged this approach. We reviewed our experience with primary hyperparathyroidism to determine if localization study-aided unilateral neck exploration is sufficient for a cure. MATERIALS AND METHODS: Retrospective chart review of patients with primary hyperparathyroidism. RESULTS: Sixty-eight patients underwent surgery for primary hyperparathyroidism. Forty-four patients were treated with localization study-aided unilateral neck exploration, and 24 patients were treated with bilateral neck exploration without preoperative localization studies. The most successful preoperative localization study was the technetium 99m sestamibi (T99mS) scan which correctly identified the location of adenomas in all cases in which it was used (n = 15). All patients were treated with unilateral neck exploration and were cured. This success was matched only by surgical exploration (n = 24). CONCLUSION: Unilateral neck exploration based on the results of a T99mS scan can be used as an initial approach for primary hyperparathyroidism if the scan identifies a solitary lesion. The second gland on the same side of the lesion should be biopsied, and if it is normal, the opposite side of the neck may be left undisturbed. If the second gland is not normal, or if the T99mS scan shows multiple lesions, bilateral neck exploration should be performed.     

Nuclear medicine imaging of the parathyroid

Nuclear medicine sestamibi parathyroid imaging is now a standard preoperative assessment for patients with hyperparathyroidism.Since the introduction of Technetium-99m (99mTc) sestamibi for parathyroid imaging in 1989 there has been a steady refinement in the imaging technique. The accuracy is determined by the scan technique employed, with the dual-isotope (123Iodine/99mTc sestamibi)scan providing better accuracy than the simpler sestamibi washout method. Now the pathologic parathyroid process can be localized preoperatively with great confidence, limiting the time and extent of the neck dissection and allowing a significant number of parathyroid surgeries to be performed as outpatient procedures.     

The influence of intraoperative parathyroid hormone monitoring on the surgical management of hyperparathyroidism.

OBJECTIVE: To examine the role of intraoperative rapid parathyroid hormone (PTH) monitoring in the surgical management of hyperparathyroidism. DESIGN: Thirty-eight-month retrospective review. SETTING: Tertiary care academic medical center. PATIENTS: One hundred consecutive patients undergoing surgery for primary hyperparathyroidism. INTERVENTION: All patients underwent preoperative technetium Tc 99m sestamibi scan localization and intraoperative blood PTH monitoring by means of a rapid (12-minute) immunochemiluminometric assay. MAIN OUTCOME MEASURES: The influence of intraoperative PTH levels on extent of surgical dissection and achievement of postoperative normocalcemia. RESULTS: Intraoperative PTH levels dropped an average of 64%, 75%, and 83% at 5, 10, and 20 minutes, respectively, after excision of all hyperfunctioning parathyroid tissue. A PTH decrease of 46% or more at 10 minutes and 59% or more at 20 minutes after excision of hyperfunctioning tissue was predictive of postoperative normocalcemia. In 79 patients (79%), the sestamibi scan provided accurate preoperative localization; all but 1 of these patients were treated successfully, most often with a limited, gland-specific dissection. In 24 patients with inaccurate, negative, or misleading preoperative sestamibi scans, 23 (96%) were treated successfully with the use of the intraoperative PTH assay. CONCLUSIONS: The rapid intraoperative PTH assay accurately predicts postoperative success in patients with primary hyperparathyroidism. The rapid PTH assay allows for greater confidence in performing limited dissections in well-localized uniglandular disease. In cases of inaccurate preoperative localization, the rapid PTH assay directly affects surgical decision making and provides greater confidence in determining when surgical success has been achieved.     

Technetium99m-sestamibi scanning before initial neck exploration in patients with primary hyperparathyroidism

Technetium99m (Tc) sestamibi (mibi) has been proposed as an alternative to the standard radionuclide imaging technique of thallium 201 chloride-^99mTc pertechnetate subtraction scan (TTS) in patients with primary hyperparathyroidism. In the present study, mibi was evaluated as an alternative to TTS in 37 patients who had either mibi-^99m-Tc pertechnetate subtraction scans, mibi-iodine123 (I) subtraction scans or mibi single isotope wash-out scans. There were 30 females and 7 males with an average age of 57 years (range, 27–78 years). Parathyroid adenomas were found in 35 patients and hyperplasia in 2. Twenty-eight mibi scans were positive and 25 of these correctly localized the parathyroid abnormality for a sensitivity of 68% (25 of 37) and a positive predictive value of 89% (25 of 28). There were 3 false-positives (8%) and 9 false-negatives (25%). The scan was not helpful in either patient with parathyroid gland hyperplasia. Mibi-¹²³I substraction was the most accurate scan and was diagnostic clinically in all 7 patients studied. Mibi scans were significantly more likely to identify inferior rather than superior adenomas (P = 0.01). Twenty-seven of the 37 patients also had a TTS which was correct in only 37% of cases while the mibi scan was correct in 68% (P = 0.02). However, routine use of nuclear scanning with mibi was still not supported by these data. Further clinical evaluation of various techniques may improve accuracy. Since mibi was significantly more accurate than TTS, it should be considered preferentially when radionuclide imaging is used in patients with recurrent hyperparathyroidism.Presented at the combined meeting of the Society of Head and Neck Surgeons and the European Organization for Research and Treatment of Cancer, Paris, France, 25–28 May 1994     

Preoperative parathyroid localization: correlating false-negative technetium 99m sestamibi scans with parathyroid disease

OBJECTIVE/HYPOTHESIS: The recent trend toward minimally invasive directed parathyroid surgery has increased the surgeon's reliance on preoperative parathyroid localization. Technetium Tc 99m sestamibi scanning is generally viewed as the gold standard for preoperative localization, with reported sensitivities of 75% to 100% and specificities of 75% to 90%. However, in each reported series there exists a group of patients in whom preoperative localization is either equivocal or negative. STUDY DESIGN: We focused on a subset of patients from our parathyroid database with false-negative sestamibi (MIBI) scans, in an attempt to elucidate features that could affect these studies. We identified 20 patients with negative preoperative scans and confirmed parathyroid disease. We compared them with 22 consecutive patients with positive scans, correlating the following variables: patient age, gender, concomitant thyroid disease (Hashimoto's thyroiditis, papillary thyroid carcinoma, thyroid adenoma), preoperative parathyroid hormone values, location and number of enlarged parathyroid glands, parathyroid weight, and the relative proportion of chief cells, clear cells, oxyphil cells, and adipose tissue. METHODS: Retrospective chart review of clinicopathological and radiological findings. RESULTS: We found that patients with false-negative scans were more likely to have an enlarged parathyroid containing a high proportion of clear cells (P =.01). A trend was seen (P =.1) correlating increased parathyroid fat content and false-negative scans. Conversely, positive preoperative scans were more likely to be associated with a higher percentage of oxyphil cells (P =.02). Univariate analysis for other variables, as well as logistic regression analysis, did not achieve statistical significance. CONCLUSIONS: To date, the present study is the largest clinicopathological review of patients with false-negative sestamibi scans. Technetium Tc 99m uptake correlates with parathyroid oxyphil cell content, and false-negative scans can occur with parathyroid glands containing predominantly clear cells.     

Utility of Preoperative Radionuclide Scanning for Primary Hyperparathyroidism

This study retrospectively reviews 60 cases of primary hyperparathyroidism, 21 of whom underwent technetium 99 sestamibi scanning and 10 of whom underwent thallium 201/technetium 99 pertechnetate scanning preoperatively. The sestamibi and thallium scans demonstrated an 89.5% and a 62.5% sensitivity rate for adenoma, respectively. Neither scan demonstrated hyperplastic glands well. Although the scans localized adenomatous glands to the correct side well, the ability to localize them more discretely was 68.4% and 62.5%, respectively. In cases of solitary adenoma the effect of an accurate preoperative scan on operative time for bilateral exploration was not significant, whereas the experience of the attending surgeon was significant. Also, the cost of the scans at our institution was greater than the cost of the time saved in performing even unilateral neck exploration. Thus preoperative radionuclide scanning is not cost-effective for the initial exploration of patients with primary hyperparathyroidism and is insufficiently sensitive to make routine unilateral neck exploration for adenoma consistently effective.     

Methylene Blue and Sestamibi: Complementary Tools for Localizing Parathyroids

Objective To determine the value and correlation between sestamibi scan and methylene blue staining for localization of parathyroid glands in patients with primary hyperparathyroidism. Study Design Nonrandomized convenience sample, followed prospectively. Methods Twenty‐three consecutive patients underwent 24 operations for primary hyperparathyroidism. All patients underwent preoperative technetium 99m–sestamibi planar scintigraphy, preoperative administration of 7.5 mg/kg methylene blue initiated within 60 minutes of surgical incision, and surgical neck exploration supervised by a single surgeon. Results All patients were cured of hypercalcemia. Sensitivity for sestamibi and for methylene blue staining was 76% and 79%, respectively. Specificity for sestamibi and for methylene blue was 98% and 93%, respectively. Agreement between sestamibi and methylene blue was 96%. Conclusions Sestamibi scanning and methylene blue staining are useful, complementary localizing tools for patients undergoing surgery for primary hyperparathyroidism. When used together, these studies decrease operative time, justify unilateral exploration in patients with parathyroid adenoma, and increase the ease of identification of hyperplastic parathyroid glands.     

Directed parathyroid exploration: evolution and evaluation of this approach in a single-institution review of 346 patients

OBJECTIVES/HYPOTHESIS: Critical evaluation of a directed exploration protocol used by a single surgeon in the management of surgical parathyroid disease. STUDY DESIGN: Retrospective chart review was made of patients surgically managed for hyperparathyroidism at an academic tertiary care center. METHODS: Three hundred forty-six patients were evaluated for biochemically proven hyperparathyroidism between March 1995 and February 2002. A directed exploration protocol was implemented in appropriately selected patients with primary hyperparathyroidism and in patients with secondary or tertiary hyperparathyroidism requiring repeat operation. The protocol included preoperative technetium-99m sestamibi imaging for hyperfunctional parathyroid localization, targeted neck exploration, rapid intraoperative parathyroid hormone determination, and limited-stay discharge from the ambulatory surgical recovery unit. Data collection was accomplished by entering patient evaluation, management, and outcome information prospectively into collective case report forms. A retrospective analysis of the data was conducted for the purpose of evaluating the effectiveness of the protocol. RESULTS: Sustained normocalcemia beyond 6 months postoperatively was achieved in 323 of 327 (99%) patients with primary hyperparathyroidism. Eighty-four percent (84%) of patients with secondary or tertiary hyperparathyroidism achieved normocalcemia or had resolution of symptoms as a measure of therapeutic success. The complication rate for the entire series of patients was 2.8%. Ninety-two percent of positive findings on sestamibi scan correctly predicted the location of an adenoma, whereas a negative finding accurately predicted the absence of an enlarged gland in a "usual" location in 81% of patients. Twenty-six patients (9%) had a false-positive finding on the scan, whereby a solitary adenoma was found contralateral to the side indicated by the scan. Overall, the positive predictive value for sestamibi imaging in the series was 91%. Intraoperative parathyroid hormone determination yielded an overall rate of reduction of 80% from preoperative levels during directed exploration. Sustained normocalcemia was achieved in all patients in whom intraoperative parathyroid hormone determination demonstrated a minimum decline of 50% from preoperative levels following resection of hyperfunctional parathyroid tissue (adenoma[s]). The majority (72%) of patients were managed in an outpatient (ambulatory surgery) setting and were discharged to home within 8 to 12 hours after surgery. CONCLUSION: The directed exploration protocol for surgical management of hyperparathyroidism generated surgical rates of success that were as good as and, in most cases, improved over that of traditional bilateral exploration. This achievement was associated with low morbidity and reduced time and facility utilization, conveying improved cost-effectiveness. This surgical strategy should serve to enhance the capability of the surgeon to safely and efficiently manage the majority of patients with surgical parathyroid disease.     

Predictors of accuracy in preoperative parathyroid adenoma localization using ultrasound and Tc-99 m-Sestamibi: A 4-quadrant analysis

Purpose

To compare the accuracy of preoperative parathyroid adenoma localization in patients with primary hyperparathyroidism (pHPT) due to a single adenoma using a detailed 4-quadrant analysis and to identify patient and tumor characteristics associated with accurate preoperative localization.

Materials and Methods

Retrospective review of 203 patients who underwent parathyroidectomy for pHPT due to a single adenoma between 2008 and 2011. Results from preoperative ultrasound and Tc-99 m-sestamibi were compared to operative findings to determine accuracy of localization studies. Associations between clinicopathologic features and accurate preoperative adenoma localization were evaluated.

Results

Ultrasound was performed on 198 patients, sestamibi on 177 patients, and both on 172 patients. Accurate localization occurred significantly more often for ultrasound than sestamibi (63% vs. 41%, P < 0.001). For ultrasound, accurate localization was found in patients with larger or heavier adenomas, those with adenomas located inferiorly, patients not having a reoperative procedure, and patients with higher post-operative serum calcium levels. For sestamibi, greater adenoma size or weight, adenomas located inferiorly, and patients with associated thyroid cancer on pathology were most predictive of accurate preoperative localization.

Conclusions

Our results provide evidence that ultrasound is more accurate in localizing parathyroid adenomas in patients with pHPT due to a single adenoma when compared to sestamibi scan using 4-quadrant location analysis and may be the preferred preoperative imaging modality in these patients. No significant preoperative patient factors were associated with accurate localization by ultrasound or sestamibi, but adenoma size, weight, and location in an inferior position were predictive of accurate preoperative localization.     

Osteitis Fibrosa Cystica Mistaken for Malignant Disease

A 65-year-old man with back pain had plain radiographs that showed multiple osteolytic bone lesions of the pelvis, femur and L-spine; an magnetic resonance imaging scan of the L-spine showed extensive bony resorption with a posterior epidural mass involving the L1 spinous process; these findings suggested multiple myeloma or bony metastasis. However, all serology testing was negative. The parathyroid hormone and serum calcium levels were found to be abnormally elevated. A fine needle aspiration biopsy suggested that the L-spine lesion was consistent with the diagnosis of osteitis fibrosa cystica. A pathological fracture of the spine compressed the spinal cord, and surgical intervention was required. The neck computed tomography and Tc-99m sestamibi scan showed a solitary parathyroid mass. A minimally invasive parathyroidectomy using intraoperative parathyroid hormone monitoring was performed and two enlarged parathyroid glands identified. This case illustrates the importance of the consideration of a rare brown tumor associated with primary hyperparathyroidism in patients with the bone lesions suggestive of a malignancy.     

Sestamibi scans and intraoperative parathyroid hormone measurement in the treatment of primary hyperparathyroidism

OBJECTIVE: To assess the value of preoperative sestamibi scanning and intraoperative parathyroid hormone (IOPTH) measurement in the treatment of patients with primary hyperparathyroidism due to multiple gland disease (MGD). DESIGN: Retrospective medical record review. SETTING: Tertiary care academic medical center. PATIENTS: The study population comprised 383 consecutive patients who underwent surgery for primary hyperparathyroidism at Long Island Jewish Medical Center, New Hyde Park, NY, between June 1, 1999, and January 31, 2002. INTERVENTIONS: Sestamibi scanning, IOPTH measurement, bilateral parathyroid exploration, and minimally invasive parathyroid surgery. MAIN OUTCOME MEASURES: Rate of postoperative persistent hyperparathyroidism. RESULTS: A total of 376 patients met the requirements for inclusion in the study. There were 275 women (73%) and 101 men (27%). Of the patients, 325 (86%) had single adenomas, 28 (7%) had double adenomas, 16 (4%) had 3 or more abnormal glands, and 1 had parathyroid cancer. There were 9 cases (2%) of persistent or recurrent hypercalcemia after surgery. Duration of follow-up ranged from 1 to 37 (median, 7) months. The sensitivity of sestamibi scanning for detecting MGD was 23%, and the positive predictive value was 63%. Using the requirement that the IOPTH level fall by 50% from the first baseline and into the normal range, MGD was distinguished from solitary adenoma in 36 (88%) of 41 cases. CONCLUSIONS: The combination of preoperative sestamibi scanning and IOPTH measurement is effective in identifying cases of MGD and allows successful minimally invasive parathyroidectomy in most patients.     

The diagnostic utility of computed tomography for preoperative localization in surgery for hyperparathyroidism

OBJECTIVES/HYPOTHESIS: Successful unilateral or minimal-access parathyroid exploration and reoperative surgery of the parathyroid glands requires accurate preoperative localization of parathyroid disease. Although ultrasound and nuclear imaging techniques have an established role in this regard, the use of computed tomography (CT) for parathyroid exploration is not well understood. The purpose of the present study was to better define the diagnostic utility of CT in preoperative localization of the abnormal gland in surgery for hyperparathyroidism. STUDY DESIGN: Retrospective cohort study. METHODS: All parathyroid explorations performed at Oregon Health and Science University (Portland, OR) between 2000 and 2002 were reviewed. The study group was limited to patients with hyperparathyroidism in whom localization failed preoperatively using ultrasound and/or sestamibi scanning and subsequent investigation using CT imaging was performed. Operative, pathological, and imaging reports were then analyzed to assess the accuracy of CT imaging for localizing parathyroid disease. RESULTS: Twenty-two patients with hyperparathyroidism were investigated preoperatively using CT imaging. Parathyroid exploration was successful in all but one patient, leaving 21 patients in all in the cohort. The majority of cases (67%) were reoperative, and all patients had previously undergone inconclusive ultrasound and/or sestamibi scanning. Computed tomography correctly localized parathyroid disease in 18 (86%) of the 21 patients who underwent successful extirpation of parathyroid disease and was able to identify abnormal glands with equal utility in the neck and the chest. CONCLUSION: When ultrasound or sestamibi are unsuccessful, CT imaging can provide valuable preoperative localizing information before surgery for hyperparathyroidism, particularly in patients with recurrent or persistent disease.     

Advantages of a targeted approach in minimally invasive radioguided parathyroidectomy surgery for primary hyperparathyroidism

OBJECTIVE: In a large series of patients, we associated the need for preoperative parathyroid hormone (PTH) and calcium levels as a vital component in our approach to the radioguided minimally invasive parathyroidectomy (MIRP) procedure. Our objective was to determine whether these preoperative levels indeed complemented the procedure. Our study also included a postoperative assessment of excised gland volume and length of operation. STUDY DESIGN: This was a prospective cohort study. METHODS:: One hundred seventy-three patients with primary hyperparathyroidism enrolled in our radioguided MIRP protocol. Patients were divided into groups based on the results of sestamibi scans. Comparisons were made between these results and the assessed preoperative PTH and calcium levels and the postoperative excised gland volume and length of operation. RESULTS: PTH and calcium levels did not statistically relate with the likelihood of having a "positive," "equivocal," or "negative" sestamibi scan, but the volume of excised gland was significantly different among the three groups (P < .01). There was no significant difference between positive and equivocal scans (P = .40). Operative time was significantly different between positive and equivocal scans (P < .01), positive and negative scans (P < .01), and equivocal and negative scans (P < .01). CONCLUSIONS: Routine preoperative PTH and calcium levels are necessary for the biologic diagnosis of hyperparathyroidism, but they do not appear to relate to the outcome of a sestamibi scan and therefore do not complement the radioguided MIRP procedure. Because the size of the affected gland, however, did correlate with a positive sestamibi scan, we conclude that as the volume of the gland increases, so does the likelihood of a successfully chosen minimally invasive surgical approach.     

Minimally invasive parathyroidectomy: the role of radio-guided surgery

OBJECTIVES: Objectives were to review our current experience with radio-guided parathyroid surgery and to compare various techniques of minimally invasive parathyroidectomy. STUDY DESIGN: 1) To review our recent experience of radio-guided gamma probe localization during surgery for primary hyperparathyroidism and 2) to compare the intraoperative findings with the preoperative sestamibi scan. METHODS: Analysis was made of the 10 most recent surgical procedures for primary hyperparathyroidism at a single institution to compare the operative localization with preoperative sestamibi scan and to determine the radioactivity in the tissue removed during surgery, such as parathyroid adenoma, normal parathyroid gland, thyroid tissue, or lymph nodes. RESULTS: The sestamibi scan was able to localize the enlarged parathyroid gland in eight patients. Although gamma probe was helpful in localizing the parathyroid gland, the identification of an enlarged parathyroid gland was directly based on the preoperative findings of sestamibi scan. In the remaining two patients, the intraoperative gamma probe was not helpful. CONCLUSIONS: The major advantage of gamma probe in the series was to evaluate the radioactivity in the tissue that was removed and to determine whether it was an enlarged parathyroid gland, lymph node, thyroid tissue, or fatty tissue. The radio-guided surgery did not add substantially to the surgical procedure in patients in whom the sestamibi scan had localized the enlarged parathyroid gland preoperatively.     

Usefulness of computed tomography and magnetic resonance in the preoperative diagnosis for hyperparathyroidism

Sonnography and Tc-99m sestamibi scintigraphy are the most requested preoperative imaging tests nowdays in the surgery of hyperparathyroidism. The aim of our article is to know if Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) are useful as a location study and in which cases it would be more justified to ask these radiologic techniques. For that we report our results with 29 patients at all diagnosed as hyperparathyroidism (26 primary forms and 3 secondary ones) and operated by our E.N.T. Department later. On 20 of them a cervical CT was asked before the parathyroidectomy and on the rest 9, a MRI with sensitivities of 65% and 88.9% respectively. We think both complementary explorations must not be solicited by routine but they can represent a help in the cases in that sonnography and scintigraphy are not able to show the possible adenoma or hiperplasia, particularly in recurrent hyperparathyroidisms, reinterventions or suspect of parathyroid glands in an atypical location.