Tc Sestamibi Research Articles

Superior Parathyroid Masquerading as Retropharyngeal Lymph Node.

Ectopic parathyroid glands have been reported with an incidence of 2-22%. Undescended parathyroid glands, defined as glands situated above the carotid bifurcation or > 1cm cranial to the superior pole of the thyroid gland, comprise 2-7% of all ectopic parathyroid glands. We report a case of incidentally discovered parathyroid gland located in the retropharyngeal space at the level of the oropharynx. The patient in this report was a 60-year-old female with squamous cell carcinoma of the tonsil T2N0M0 with MRI showing a hyperintense ovoid structure, medial to the carotids at the level of the oropharynx, corresponding to the location of the lateral group of retropharyngeal lymph nodes. Patient underwent transoral ultrasonic radical tonsillectomy along with a retropharyngeal lymph node dissection by the transcervical route. Postoperative histopathology revealed the retropharyngeal node sampled to be a normal parathyroid gland. "High" undescended parathyroid gland as reported here along with 4 other cases of infratemporal fossa parathyroid glands reported previously, can be the cause for recurrent missed adenomas. Being extracervical in location, these are likely to be missed if the skull base has not been included in the preoperative Tc-99 sestamibi scan and also during bilateral neck exploration.

The Comparison of Low and High-Dose Scintigraphy Findings in Patients with Primary Parathyroid Lesions in which Intraoperative Gamma-Probe was Applied.

We aimed to evaluate the effectiveness of high-dose and low-dose use of radioactive material in intraoperative gamma probe application methods in patients diagnosed with primary hyperparathyroidism and planned for surgery. 47 patients with primary hyperparathyroidism underwent minimally-invasive parathyroid surgery (MIS) after preoperative imaging studies consisting of ultrasonography (USG) and sestamibi parathyroid scintigraphy (SPS) showed a possible primary parathyroid lesion (PPL). All patients received Tc-99 sestamibi on day-of-surgery imaging (DOSI) to help with the localization of a primary parathyroid lesion (PPL) via both DOSI and intraoperative gamma probe (IGP). Patients in Group I were administered 20-25 mCi Tc-99m sestamibi (methoxy isobutyl isonitrile) and images were obtained at the 20th and 120th minutes. Patients in Group II were administered 8-10 mCi doses and images were obtained at the 20th and 40th minutes. Two nuclear medicine specialists independently evaluated the images. Lesions in the localizations determined by DOSI and IGP were compared with the histopathological results of these lesions. 47 patients, 35 females, and 12 males were included in the study. The mean age of 28 patients in the first group given the high dose was 54 (41-60), and the mean age was 48 (42-57) in the second group given the low dose (p=0.011). In the group given low-dose radioactive material during intraoperative gamma probe application, the observer's sensitivity, specificity, positive, and negative predictive values for finding pathology were 61.1, 100, 100, and 12.5, respectively. In the group given high-dose radioactive material, the same values were 90.9, 33.3, 50, and 83.3, respectively. While the success of MIS increases with the use of DOSI and IGP in large lesions, the success decreases with the prolongation of the accumulation time of the given dose. In the intraoperative gamma probe technique used in primary hyperparathyroidism patients, the method used with low-dose radioactive material has lower sensitivity but higher specificity in estimating the post-operative pathology compared to the high-dose technique.

AN INTERESTING CASE OF KNOCK KNEE

Primary hyperparathyroidism is a generalized disorder of calcium, phosphate, and bone metabolism due to an increased secretion of parathyroid hormone. The manifestations may be subtle, and the disease may have a benign course for many years or a lifetime. If the patients are symptomatic , the most commonly involved system include the renal and the skeletal system. Herein we present a case of 16 year old male who presented with complaints of multiple large joint pain and progressive deformity of both knees over the past 1 year. Physical examination revealed bilateral genu valgum. Investigations taken showed elevated serum calcium levels, parathormone levels, alkaline phosphatase levels and low levels of vitamin D. Skeletal radiograph taken showed evidence of osteitis brosa cystica along with salt and pepper appearance of the skull. USG Neck showed evidence of left parathyroid adenoma and a Tc99 Sestamibi parathyroid scintigraphy scan conrmed it. Patient underwent inferior parathyroidectomy. Post procedure, patient's parathormone levels were within the normal limits and hence was discharged with calcium and vitamin D supplements.

Parathyroid adenoma versus primary hyperparathyroidism

This is a narrative review of literature. We focus on the issue of identifying a parathyroid adenoma without anomalies of function (non-functioning parathyroid adenoma) which is incidentally detected or not, via routine neck ultrasound or through advanced imaging techniques which are mostly performed for other conditions (like assessment of a non-parathyroid oncological condition or emergencies – related neck exploration). The traditional diagnostic of primary hyperparathyroidism is exclusively a biological one based on high calcium and parathormone (PTH), and only a second step of assessment actually involves the localization procedures. However, the detection of a parathyroid tumor does not necessarily mean that it is associated with an over-secretion of PTH. Ultrasound is usually followed by Tc Sestamibi scintigram and/or computed tomography is order to refer the patient to parathyroidectomy in cases with biological confirmation of primary or renal hyperparathyroidism; yet, in cases with non-functioning profile, there is no clear indication of further imaging exploration. In conclusion, the identification of a parathyroid adenoma is rarely associated with a normal parathyroid function and this entity, which most probably is an incidentaloma, is not a subject of particular guidelines yet. Whether it is necessary to continue with other imaging techniques as typically seen in primary hyperparathyroidism is still an open issue, and so is the panel of indications to perform its surgical removal instead of serial follow-up.

English

BACKGROUND The differentiation of tumour progression from treatment-induced changes is critical in evaluating response to therapy among patients with gliomas. Although conventional magnetic resonance imaging (MRI) is invaluable in the overall assessment of such lesions, it is often difficult to differentiate between these two entities. We wanted to evaluate the role of contrast-enhanced MRI (CE MRI) and magnetic resonance spectroscopy (MRS) and correlation with 99 m Tc Sestamibi single-photon emission tomography (SPECT) in differentiating tumour progression from post-therapy changes in patients with glioma. METHODS This was a cross-sectional study. Being a rare disease, all adult patients (25 in number) with brain glioma reporting to the hospital for over a period of 12 months were included in the study. CE MRI, MRS and SPECT were performed at three months, six months and 12 months’ post-surgery and radiotherapy. The ratios for choline (Cho) / N-acetyl aspartate (NAA) and choline (Cho) creatine (Cr) were obtained from the areas suspicious for tumour progression on CE MRI and were correlated with the presence or absence of uptake on SPECT. These findings were correlated with the patients’ clinical course and tumour histopathology. RESULTS Both choline (Cho) / N-acetyl aspartate (NAA) and choline (Cho) / creatine (Cr) ratios had high detection rates for tumour progression when cut-off values of > 1.75 were used. For the Cho / NAA ratio, the sensitivity and specificity were 93.7 % and 100 %, respectively. The sensitivity and specificity for the Cho / Cr ratio were 81.3 % and 88.9 %, respectively. The sensitivity and specificity of 99 m Tc Sestamibi SPECT were 87.5 % and 100 %, respectively. CONCLUSIONS MRS and SPECT have high sensitivity and specificity for diagnosing tumour progression and must be used in conjunction with conventional CE MRI in the posttherapy setting. KEYWORDS Glioma, Progression, Post-Therapy Changes, MRI, MRS, SPECT

Severe Refractory Hypocalcemia After Administering Zoledronic Acid for Osteoporotic Fracture in Primary Hyperparathyroidism That Is Complicated Into Hungry Bone Syndrome: A Case Report

Zoledronic acid is a very effective (IV) amino bisphosphonate which is indicated in osteoporosis, hypercalcemia of malignancy, multiple myeloma, Paget’s disease, and bone metastases from solid tumors. Bisphosphonate inhibits bone resorption through actions on osteoclast activity resulting in increasing bone density. Unfortunately, there are side effects associated with zoledronic acid one of those is mild to moderate hypocalcemia. Hungry Bone Syndrome (HBS) is defined as a severe drop in calcium levels less than 2.1 mmol/L and/or prolonged hypocalcemia for more than 4 days post parathyroidectomy. Most seen in patients’ who have secondary hyperparathyroidism compared to primary hyperparathyroidism. The sudden drop of parathyroid (PTH) levels post parathyroid resection after a prolonged duration of high PTH levels causes net calcium to move into the bone, this is the most proposed hypothesis. The authors report a case of a 32 years old female known case of severe osteoporosis presented to the emergency department complaining of left hip pain after a short height fall admitted as a case of pathological fracture. Furthermore, upon admission was vitally stable although on examination the patient had left side hip pain and tenderness otherwise unremarkable. Initial lab investigation showed a calcium level of 2.57 mmol/L and PTH level 37 pmol/L otherwise electrolytes and full blood count were unremarkable. Radiological investigations were done, and an X-ray has shown a left hip fracture where the patient underwent an operating room for fixation. In addition, a 99mTc-HDP bone scan revealed hyperparathyroidism and brown tumor. 99m Tc SESTA-MIBI whole body scan suggested metabolic bone disease. Furthermore, the parathyroid showed suggested typical parathyroid adenoma below and lateral to the lower pole of the left thyroid lobe. The ultrasound of the thyroid showing a well-defined hypoechoic nodule 2.5x1.15 cm with significant hypervascularity is seen, which is most likely to be enlarged left parathyroid gland. Thus, diagnosis of primary hyperparathyroidism has been reached with parathyroid adenoma which was resected during a hospital stay. The patient received pre-op zoledronic acid as a treatment for osteoporosis prior to the hip operation. After the parathyroid adenoma resection, the patient had a sudden drop of PTH and developed hypocalcemia which was 1.1 mmol/L. Thus, the complication of post operated parathyroid adenoma of HBS diagnosis has been made. Interestingly the patient needed to increase the length of stay of the hospital due to refractory hypocalcemia where the patient has been receiving IV calcium and vitamin D supplementation which hadn’t improved until a month of IV calcium gluconate. Although, the patient didn’t develop any signs or symptoms of hypocalcemia.

MON-376 Head to Toe Hyperparathyroidism - Impending Hyperparathyroid Crisis and Subsequent Crystal Arthropathies

The myriad of presentations associated with PHP are well established, however gout is not commonly associated with this disease. Additionally, it is unusual to see multiple threatening and potentially debilitating complications occur concurrently in one patient.An asymptomatic elderly male with hypertension presented to the PCP for the first time and was found on routine blood work to have a serum creatinine of 4.03 mg/dl, a serum calcium of 12.1mg/dl, and a PTH of 831.7ng/L. Subsequent Tc-99 Sestamibi scanning suggested that the source was both a single right inferior parathyroid adenoma and an ectopic mediastinal adenoma. At the initial encounter the patient’s hypercalcemia was treated with IV fluid resuscitation and calcitonin then subsequently cinacalcet. Renal ultrasound at that time showed normal sized kidneys with several cysts, and phosphate levels ranged from 2.0-3.9 mg/dl (range 2.5-4.5mg/dl. The patient’s serum calcium was controlled at 10.44mg/dl, and his renal function improved to a serum creatinine of 3.08mg/dl. Prior to discharge patient developed acute left knee pain, and was found to have an inflammatory arthritis, with urate crystals seen. The patient was diagnosed with an acute gout flare, which responded well to colchicine and was discharged. The patient eventually underwent parathyroidectomy, which showed a large 4cm left superior parathyroid as well as a large right superior parathyroid gland extending into the mediastinum. Pathology was consistent with parathyroid hyperplasia. After surgery, the patient developed hungry bone syndrome, with an admitting serum level calcium of 6.05mg/dl, serum magnesium of 2.00mg/dl, serum phosphorus of 2.8mg/dl, and serum potassium of 5.1mg/dl, with clinical features of tetany and weakness that resolved after two days with calcium and calcitriol administration. He again had an acute monoarticular arthritis prior to discharge that had both urate and calcium pyrophosphate crystals in the joint fluid and again responded well to colchicine and glucocorticoids. He was eventually discharged on vitamin D and calcium supplementation, with cinacalcet and colchicine.This case illustrates the multiple clinical teaching points that exist in primary hyperparathyroidism, including both types of presentation and potential complications. It also expresses the need to be vigilant of some rarer clinical features, such as potential hyperparathyroid crisis and multiple enlarged parathyroid glands. Physicians should also be wary of both gout and CPPD, as well as complications that occur post parathyroidectomy such as hungry bone syndrome.

SAT-364 Brown Tumor of the Mandible in Severe Uncontrolled Primary Hyperparathyroidism

Background: Brown tumors are a part of the complex “osteitis fibrosa cystica” which is a diffuse resorptive process of the bone resulting from uncontrolled hyperparathyroidism. Although these brown tumors were fairly common in the past1, the incidence of brown tumors is now extremely rare in the United States due to early diagnosis and treatment of hyperparathyroidism. Here we describe an unusual presentation for osteitis fibrosa cystica. Clinical Case: A 38 year old woman was admitted to the hospital with rapidly growing facial swelling in June 2019. The swelling initially appeared in January 2019 and had rapidly increased in size since April 2019. The mass was malodorous, painful and interfered with oral intake. The patient smoked 1 pack per day for 13 years. A CT scan of the head and neck with contrast showed a 3.6 x 4.5 x 3.3 cm mass destroying the right mandibular body, involving the right platysma muscle and displacing the central and lateral incisor teeth and was concerning for malignancy. The initial impression was that this was likely a squamous cell carcinoma with local and perhaps distant metastases, complicated by humoral hypercalcemia of malignancy and she was admitted for management.Upon admission, her calcium level was 14 mg/dL, albumin 4.1 g/dL, phosphorus 1.4 mg/dL PTH level was 890 pg/mL and vitamin D level was 22 ng/mL. Since the high PTH did not fit with hypercalcemia of malignancy, further evaluation was undertaken. A thyroid ultrasound showed a 4.6 x 1.8 x 1.5 cm isoechoic, heterogeneous lesion in the left lower pole, and Tc-99 sestamibi scan suggested parathyroid origin. The biopsy of the mouth lesion showed fibro histiocytic proliferation with multiple giant cells, negative for malignancy and consistent with a brown tumor. CT scan of the chest, abdomen and pelvis did not reveal any other masses or lytic lesions. . A skeletal survey showed another 2 cm lytic lesion in the proximal left humeral metaphysis which was not biopsied.On parathyroidectomy, the patient was found to have an enlarged left inferior parathyroid gland measuring 3.3 x 3.0 x 0.8 cm weighing 7.093 grams. Intraoperatively PTH level decreased from 890 pg/mL to 69 pg/mL. Her calcium levels returned to normal post-operatively and she was discharged home. Pathologic examination report revealed the mass to be a parathyroid adenoma. The patient reports a reduction in the size of her mandible mass since the surgery.Conclusion: Although uncommon, brown tumors can be seen in uncontrolled primary hyperparathyroidism. The mandible is a common site, though, as in this case, it is less common for it to be the only site affectedReference:1. Rosenberg, E. H. (1962). Hyperparathyroidism. A review of 220 proved cases with special emphasis on findings in the jaws. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 15(2), 84–94.

Novel Findings on SPECT-CT Tc-99 Sestamibi Imaging for Primary Hyperparathyroidism

BackgroundThe addition of SPECT-CT to Tc-99 sestamibi has become a valuable tool for parathyroid localization in primary hyperparathyroidism (PHP). However, the enhanced sensitivity of this test can lead to unexpected and significant findings. We sought to identify the frequency and types of nonparathyroid detections by SPECT-CT. Materials and methodsWith institutional approval, we reviewed all SPECT-CT studies performed for PHP between October 2012 and August 2018 for incidental nonparathyroid abnormalities. The electronic medical record was referenced to determine the type of lesion confirmed by additional evaluation. ResultsAmong 2413 studies, 652 patients (27%) had 677 (28%) nonparathyroid findings. The most common were thyroid nodules (331/677, 49%), including 47 (6.9%) malignancies to date: 40 papillary thyroid cancers (11 microcarcinomas), five follicular thyroid cancers, one medullary carcinoma, and one noninvasive follicular thyroid neoplasm with papillary-like features. One hundred and seventy-seven patients had pulmonary nodules (26%), of whom nine were diagnosed with primary lung lesions (6 non–small-cell cancers, one small-cell cancer, one carcinoid, and one pulmonary sequestration). SPECT-CT revealed 14 patients (2.1%) with breast abnormalities, including three cancers. Nine patients (1.3%) demonstrated metastatic diseases within the lungs (4), bones (3), and mediastinum (2). One patient was diagnosed with follicular lymphoma. Two intracranial tumors were also identified, as well as dysplastic Barrett's esophagitis (1), hiatal hernia (20, 3%), and aortic aneurysm (13, 1.8%). In all, 72/677 (10.6%) PHP patients exhibited premalignant or malignant nonparathyroid SPECT-CT findings. ConclusionsIn patients undergoing localization for PHP with Tc-99 sestamibi SPECT-CT, nonparathyroid findings are frequent (27%) and can lead to newly diagnosed malignant or premalignant lesions in at least 3% of patients to date.

ROLE OF GATED SPECT USING TC 99 SESTAMIBI IN EARLY DETECTION OF SUBCLINICAL HCV RELATED CIRRHOTIC CARDIOMYOPATHY

Background: HCV is one of the health priority in Egypt due to its high prevalence. Cirrhotic cardiomyopathy in manifest stage can affect the patient’s prognosis. This study aimed to evaluate the ability of gated SPECT in detection of early HCV related cirrhotic cardiomyopathyMethods: We studied forty Child A HCV cirrhotic patients with no other cardiac risk factors by conventional echocardiography and Tc99 sestamibi gated SPECT and twenty normal persons as controls.Results: the studied group showed blunted response to stress no ischemic changes and normal right ventricular measures.Conclusions: HCV had an early effect on the heart in the form of chronotropic impairment with stress.

Diagnosis and treatment of confirmed and suspected primary hyperparathyroidism in equids: 17 cases (1999–2016)

Primary hyperparathyroidism is uncommon in equids. To describe the diagnostic findings and efficacy of treatment in equids with primary hyperparathyroidism. Retrospective case series describing 16 horses and one mule. Cases were identified by retrospective review of records at Cornell University and via an ACVIM listserv query. Inclusion criteria were an equid with hypercalcemia, normal renal function and high parathyroid hormone (PTH) or histopathological diagnosis of a parathyroid adenoma. Equids with normal PTH and PTH-related protein (PTHrP) in the face of hypercalcemia were included as suspect cases. The most common presenting complaints were weight loss (12/17) and hypercalcemia (10/17). PTH was above reference range in 12/17 cases. Suspected parathyroid tumours were localised in 12/14 equids imaged using ultrasonography alone (2/3), technetium 99m Tc sestamibi scintigraphy alone (1/1) or both modalities (9/10). Three horses did not have imaging performed. Surgical exploration successfully excised tumours in six of 10 cases. Five were located at the thoracic inlet, and surgery resulted in complete cure. One tumour was excised from the thyroid lobe, and the horse remained hypercalcemic. Four other cases explored surgically, four treated medically and three that were not treated also remained hypercalcemic. The small study size prohibited statistical analysis. Parathyroid adenomas in equids can be successfully localised with ultrasonography and scintigraphy. Surgical excision appears more likely to be successful for single gland disease at the thoracic inlet.

3173 A Mouse Model to Study Image-Guided, Radiation-Induced Cardiac Injury and Potential Clinically Targetable Biologic Mediators

OBJECTIVES/SPECIFIC AIMS: The overall objective of this study is to develop a novel, clinically-relevant, image-guided mouse model for radiation-induced cardiotoxicity, which can be used to gain insight into clinically-targetable, pathophysiologic mechanisms of cardiac injury in thoracic radiotherapy patients. METHODS/STUDY POPULATION: Photon or sham radiation will be administered at differential doses to a defined portion of the heart and/or lungs of C57BL/6 female mice using micro-CT visualization of the heart with Xstrahl’s MuriSlice Software applied to the Small Animal Radiation Research Platform (SARRP). Cardiac and lung segments from a subset of mice will be harvested at specific time points for confirmation of radiation targeting, local apoptosis assessment, and evaluation of fibrosis and vascular tissue morphology. Quantitative echocardiography, myocardial 18F-fluorodeoxyglucose positron emission tomography computed tomography (18F-FDG PET/CT), and myocardial perfusion imaging (MPI) with Technicium-99 (Tc-99) sestamibi will be implemented to identify sensitive imaging measures of cardiac injury and asses myocardial mechanics, inflammation, and perfusion deficits, respectively. Concurrently, a multiparametric analysis will be conducted to identify novel, circulating biomarkers of cardiotoxicity. RESULTS/ANTICIPATED RESULTS: We hypothesize that a clinically-relevant mouse model can be generated by the in situ, focal irradiation of a portion of heart and/or lung tissue segments, and can be used to elucidate molecular mechanisms of radiation-induced cardiac damage. We anticipate time-dependent and dose-dependent, focal histopathologic changes in the mouse heart, with cardiac fibrosis development, vascular damage, and cellular apoptosis in irradiated mice. Additionally, we anticipate that our mouse model of focal heart irradiation will reveal radiologic and biochemical changes that can be used to characterize and predict radiation-induced cardiac injury. Specifically, we expect our quantitative echocardiography, FDG-PET, and MPI parameters to identify and characterize cardiac damage that topographically matches histopathological analysis, and expect levels of select biochemical markers to differentially vary with time. DISCUSSION/SIGNIFICANCE OF IMPACT: Our mouse model of radiation-induced cardiotoxicity has the potential to shift current preclinical research paradigms to more closely mimic the radiation plans most commonly administered in clinical practice. The primary technologic innovation to be developed here is the use of the SARRP to deliver image-guided, in situ, focal radiation to a defined portion of the mouse heart. From a conceptual perspective, we propose a novel approach for phenotyping radiation-induced cardiac damage in patients undergoing chest radiation therapy, integrating sensitive radiomic and biochemical markers into a predictive model of cardiotoxicity.

Familial Paraganglioma Due to a Novel SDHB Mutation: Familial Phenotypic Heterogeneity and a Potentially Novel Manifestation

Non-paraganglioma (PGL) tumors are rare manifestations of familial PGL syndromes. Primary hyperparathyroidism has not been described in PGL syndromes. We present a 36-year-old man with a history of right carotid body tumor at 24 years and an abdominal PGL at 31 years of age. At 35 years, he developed hypercalcemia (serum Ca 2.65–2.72 mmol/l), and high parathyroid hormone of 92–131 ng/l (normal range, 15–65) and a Tc99 Sestamibi scan showed a single parathyroid adenoma which was confirmed on histopathological examination of parathyroidectomy. Recently, he was diagnosed with a left glomus jugulare which has not been operated on yet. His family history is strongly positive for PGLs. Genetic testing revealed a novel SDHB mutation (p.K137E) but the phenotype and penetrance were variable in different family members.

Recurrent 99mTc Sestamibi Emboli in the Lungs Revealed on Consecutive Rest and Stress Single-Photon Emission Computed Tomography/Computed Tomography Myocardial Perfusion Images.

Many causes of incidental focal uptake on raw data images using myocardial perfusion imaging, including malignant diseases, metastatic processes, benign pathologies, and physiological conditions, have been reported in the literature. However, iatrogenic 99mTc sestamibi emboli have not yet been reported. Herein, we demonstrated iatrogenic 99mTc sestamibi embolization on consecutive rest and stressed myocardial perfusion images at different locations.

99mTc sestamibi scintimammography. Screening mammographic non-palpable suspicious breast lesions: preliminary results.

Investigation of the diagnostic role of technetium-99m methoxyisobutylisonitrile ((99m)Tc sestamibi) scintimammography in non-palpable, suspicious breast lesions described as microcalcification, mass and increased density using mammography. 35 women with non-palpable breast lesions were enrolled in the study. Anterior, left and right lateral, ipsilateral posterior oblique images were obtained 15 min after the injection of 740 MBq of (99m)Tc sestamibi. All scintigraphic images were evaluated visually and focal increased (99m)Tc sestamibi uptake was accepted as malignant lesion. Breast lesions were classified as microcalcification (13 women), mammographic mass (16 women) and increased density (6 women). Excisional biopsy was performed in all of them irrespective of the scintigraphic results. The focally increased (99m)Tc sestamibi uptake was seen in 11 breast lesions with malignant lesions and in 4 breast lesions with benign lesions. The diffuse uptake of (99m)Tc sestamibi was seen in 18 breast lesions with benign lesions and 2 breast lesions with malignant lesions. There was no false positive result of (99m)Tc sestamibi in microcalcification group and there was no false negative result of the mammographic mass and increased density groups. Scintimammography might be a complementary method in decision making for the non-palpable, suspicious breast lesions that were evaluated as microcalcification, mass and increased density mammograpically.

Exámenes diagnósticos cardiovasculares: ¿diferencias de género en su interpretación?

Given that cardiovascular disease is the main cause of death in women, awareness of the gender differences in its diagnosis, treatment and development is essential for intervention. The role of non-invasive techniques in the assessment of women with suspected ischemic heart disease should take into account the anatomical, physiological and pathological differences which are directly related to their results and interpretation. Conventional stress tests have less sensitivity and specificity in women than in men, while thallium myocardial perfusion scans have a higher sensitivity, but not a better specificity, than the conventional stress electrocardiogram in women; and the Tc-99 sestamibi SPECT has a ∼90% specificity in women, which is similar to that in men. Tests such as stress echocardiograms have a slightly worse sensitivity in women versus men, with a comparable specificity. Nuclear magnetic resonance (NMR) and coronary CT angiography currently have a preponderant role in the study of ischemic heart disease. The clinical suspicion of cardiovascular disease in women, together with the selection of the best diagnostic technique and an adequate interpretation, favors more timely diagnoses and treatments.

The Effects of Vitamin D Level on the Results of Tc99 Sestamibi Scans for Parathyroid Adenoma Localization in Patients with Primary Hyperparathyroidism

The Effects of Vitamin D Level on the Results of Tc99 Sestamibi Scans for Parathyroid Adenoma Localization in Patients with Primary Hyperparathyroidism

Parathyroid Adenomas in Adults and Adolescents. Critical Appraisal and Surgical Strategy in 18 Cases.

Demographic, clinical presentations, laboratory and imaging data, operative findings and procedures together with pathology account and outcome from the case reports of 18 patients with documented PHP were retrospectively analyzed. Results: The male/female ratio was 1/5, with ages ranging from 16 to 58 (mean 46) years. Renal stones (n=9) and bone sufferings (n=6) were the most common modes of presentation. To these were added psychiatric and neuromuscular complaints, digestive disorders (pancreatitis and peptic ulcer) arterial hypertension and presence of a palpable nodule. Mean serum calcium and phospho-rus, alkaline phosphatase and PTH dosage together with parathyroid ultrasound and 99m Tc sestamibi scintigraphy are the most useful parameters for diagnosis. Eighteen adenomectomies were performed of which bilateral neck exploration was done in 16 patients and minimally invasive approach in the remaining two cases. In 9 situations concomitant thyroid exeresis for associated lesions or tactical purpose were done. Pathology revealed single adenoma consisting of main and oxyphil cells in 17 cases. In one case an atypical adenoma was identified and in another case three years after removal of a benign adenoma the subject presented a clinical ipsilateral recurrence which provided to be a carcinoma. Postoperative clinical and humoral outcome was favorable in all situations less the case of carcinoma which died after 14 months. Conclusions: Despite the rarity and difficulties of diagnosis in cases of PA, practitioners must be aware of potential existence of these lesions in order to apply as early and appropriate treatment where surgery is the gold standard.

Is C-11 Methionine PET/CT Able to Localise Sestamibi-Negative Parathyroid Adenomas?

Patients with primary hyperparathyroidism (pHPT) and a negative preoperative Tc-99 sestamibi (MIBI) scintigraphy are considered to have a higher risk of persistent disease. The aim of this study was to assess whether additional imaging with C-11 methionine positron emission tomography/computed tomography (Met-PET/CT) is able to localise sestamibi-negative hyperfunctioning parathyroid glands. In 50 patients (38 females, 12 males, age 13-81years) with pHPT and negative localisation procedures such as ultrasound and sestamibi, a Met-PET/CT was performed before parathyroid surgery. The results of Met-PET/CT were analysed prospectively and compared with intraoperative and histopathological findings. 22% of the patients underwent previous parathyroid and/or thyroid surgery. Met-PET/CT correctly located a single-gland adenoma in 33 of 45 (73%) patients with pHPT. In 5 patients with multiglandular disease, Met-PET/CT detected at least one hyperfunctional parathyroid gland in 4 patients (80%). In 3 patients with double adenomas, 5 of 6 parathyroids were correctly located. Overall, 40 of 57 (70%) hyperfunctioning glands were identified with Met-PET/CT. Met-PET/CT was false-negative in 12 of 50 (24%) patients and false-positive in only one case (2%). Postoperatively, 48 of 50 patients (96%) were cured. Additional pre-interventional imaging with Met-PET/CT was able to identify hyperfunctioning parathyroid glands in 74% of patients with pHPT and negative sestamibi scans, thus enabling successful parathyroid surgery.

Adherence of Tc-99 Sestamibi to Plastic Syringes Could Complicate Efforts in Dose Reduction in MPI SPECT

BackgroundMultiple disposable syringe designs are available both with and without silicone lubricant. Tc99m sestamibi variably adheres to certain syringe designs. In practice, this increases pre-injection activity to ensure constant acceptable image quality in the setting of high adherence. MethodsThe residual activity following 35 Tc99m MDP injections was used as a proxy for the dead-space residual activity. This was compared to Tc99m sestamibi injections in the same syringe in 107 injections, a syringe without lubricant in 35 injections, and a syringe without lubricant or rubber gasket in 16 injections. The syringe with lubricated barrel was disassembled and each part separately assayed to see which part demonstrated the most adherence. ResultsThe standard design demonstrated a mean adherence of 26% (SD 7.0%). This was significantly more than the 6% (SD 3.7%) demonstrated with MDP. The two designs without silicone lubricant demonstrated mean adherence of 7.2% (SD 2.3%) and 6.4% (SD 2.3%). Disassembly of the three part syringe showed the greatest adherence to the rubber gasket. ConclusionsQC procedures determining adherence in the administration syringe are warranted for any change in syringe design or manufacturer. If adherence is present, conversion to non-lubricated plastic syringes with lower and more predictable retention of Tc99m sestamibi enables more precise titration of prescribed activities and reduction of overall patient absorbed doses.