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Radioguided parathyroidectomy is a helpful tool in the armamentarium of parathyroid surgeons and is applicable to nearly all patients. This chapter outlines the clinical utility of this method and provides an outline for appropriate patient selection. We also highlight many of the potential advantages of a radioguided approach, paying special attention to pediatric and geriatric patients as well as focusing on challenges particular to parathyroid surgery including ectopically located glands, a history of previous neck exploration, and parathyroid carcinoma. Focused detail is provided on the technical aspects of employing a radioguided approach, and we share practical pearls as well as discuss pre- and postoperative care for these patients. Lastly, we provide three clinical case examples in which a radioguided approach to parathyroidectomy was beneficial.

Primary hyperparathyroidism is caused by a single parathyroid adenoma in the majority of patients. Localization of parathyroid adenomas prior to surgery has the benefit of allowing a minimally invasive approach. Over the years, multiple imaging modalities have been employed in an attempt to identify the site preoperatively, with varying degrees of success. In this study, we explore the accuracy of a combination of ultrasound and nuclear medicine planar scintigraphy with iodine-123 and technetium (99mTc) sestamibi. A retrospective study of consecutive series of 117 patients undergoing minimally invasive parathyroidectomy was carried out. Inclusion criteria incorporated clinical and biochemical evidence of primary hyperparathyroidism. All patients had at least one form of imaging: Ultrasound or nuclear medicine scintigraphy or both. The accuracy was compared with surgical findings. Gland weight was also related to imaging accuracy. A total of 101 patients underwent surgery for primary hyperparathyroidism. There was no significant difference between ultrasound and scintigraphy ability to localize a parathyroid adenoma (p = 0.738). The combination of ultrasound and scintigraphy was superior at preoperative localization compared to ultrasound (p = 0.039) or scintigraphy alone (p = 0.0078). Gland weight had no significant bearing on the accuracy of the scan (ultrasound, p = 0.89; scintigraphy, p = 0.16). Dual localization with ultrasound and scintigraphy in primary hyperparathyroidism is superior to a single imaging technique. Dual localization facilitates minimally invasive parathyroidectomy. How to cite this article Lyon A, Komolafe OO, Wilson CR, Doughty JC. Dual Localization with Ultrasound and Iodine 123 and Technetium (99mTc) Sestamibi Scintigraphy is Superior to Single Imaging Modalities in Facilitating Minimally Invasive Parathyroidectomy for Primary Hyperparathyroidism. World J Endoc Surg 2012;4(3):93-98.

Summary The aim of the study was to validate the accuracy of the exini heart software (exini) package in assessing left ventricular end-diastolic/systolic volumes (EDV, ESV) and ejection fraction (LVEF) from gated 99mTc-MIBI single-photon emission tomography (SPECT). Cardiac magnetic resonance imaging (cMRI) was used as reference. Furthermore, effects of perfusion defects and image quality in SPECT on correlation between gated SPECT and magnetic resonance imaging were investigated. Methods: Seventy patients were examined using gated SPECT (rest study, eight gates per cardiac cycle). EDV, ESV and LVEF were calculated from gated SPECT using exini. Directly before or after SPECT, cMRI (20 gates cardiac per cycle) was performed. EDV, ESV and LVEF were calculated using Simpson’s rule. Perfusion defects were quantified using the summed-rest-score (SRS). Total number of myocardial counts were used to rate image quality. Results: Correlation between results of gated SPECT and cMRI was high for EDV (R = 0·89) and ESV (R = 0·94) and good for LVEF (R = 0·78). ESV (exini 54 ± 31 ml versus cMRI 57 ± 34 ml) and LVEF (exini 62·9 ± 11·7% versus cMRI 60·6 ± 13·9%) did not differ significantly whereas exini overestimated EDV significantly compared with cMRI (exini 144 ± 41 ml versus cMRI 137 ± 36 ml; P

Background The objective of the current study was to study different functional and anatomic features of the hyperplastic gland and clinical and biochemical characteristics of renal hyperparathyroidism (HPT) patients and their relationship with the scintigraphic detection of parathyroid glands. Methods A retrospective study was performed of 40 patients with chronic renal failure (CRF) who underwent cervical surgery for HPT. Weight, histology, and localization of hyperplastic glands were recorded. Parathyroid cell proliferation was assessed by percentage of S-phase cells. Double-phase scintigraphy with technetium 99m–sestamibi and serum parathyroid intact hormone (PTHi), creatinine, calcium, and phosphate levels were performed. Results Detection of hyperplastic parathyroid glands by 99m Tc-sestamibi scintigraphy was associated with the weight and inferior localization of the glands. The functionality of the glands as reflected in serum PTHi and phosphorus levels was associated with the number of glands detected. Conclusion Double-phase 99m Tc-sestamibi scintigraphy is of limited usefulness in patients with renal HPT. Detection of hyperplastic parathyroid glands in patients with CRF depends on the weight and inferior localization of the glands. Serum PTHi, phosphorus and creatine levels are associated with the number of glands detected by means of 99m Tc-sestamibi scintigraphy.

Summary We evaluated the additional benefit of Technetium99-sestamibi (99mTc-MIBI) scanning in comparison with standard X-ray techniques for multiple myeloma patients either at diagnosis or during follow-up. Between February 2001 and January 2005, 397 whole body scans were acquired. On 229 scans performed at diagnosis, 146 (64%) were positive and 81 cases have discordant X-ray results. The sensitivity of 99mTc-MIBI and X-ray were 77% and 45% respectively. As a result of 99mTc-MIBI, 40% of asymptomatic myeloma patients were up-staged. The positivity of 99mTc-MIBI correlated significantly with all of the most relevant clinical and biological parameters. Multivariate analysis selected only high reactive C protein (P = 0·0005), bone marrow infiltration (P = 0·02) and bone pain (P = 0·002) as factors affecting 99mTc-MIBI pattern. In 22 patients with solitary myeloma, 99mTc-MIBI was positive in 86% of cases and detected more disease sites than X-ray. Among 168 scans performed during follow-up, 99mTc-MIBI presented high specificity in patients showing a complete response (CR; 86%), and correlated with myeloma activity and with response to therapy. At multivariate analysis, a positive pattern correlated with bone marrow infiltration (P = 0·002) and disease status other than CR (P = 0·03). We conclude that 99mTc-MIBI scanning is an additional diagnostic tool with a high specificity for the staging and the follow-up of multiple myeloma patients.

Background Ultrasonography (USG) and technetium-99m sestamibi (MIBI) scintigraphy are commonly used imaging modalities in the era of minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism (pHPT). However, their relative importance and actual contribution to MIP have not been prospectively assessed. Methods A total of 100 consecutive pHPT patients planning for MIP were recruited. Both USG and MIBI findings were correlated with intraoperative findings and postoperative outcome. Clinicopathologic factors were examined for potential association with a correct localizing result. Results Thirty men and 70 women (age range 13 to 93 years [median 55.5]) were included in the study. The final pathology included 98 patients with solitary adenoma and 2 patients with multiglandular disease. The sensitivities, accuracies, and positive predicted values for USG and MIBI alone were 57% vs 89%, 56% vs 85%, and 97% vs 94%, respectively. Correctly localized adenomas were significantly heavier than incorrectly localized ones. Conclusions MIBI is preferred over USG in pHPT patients planning for MIP. Weight of adenoma appeared to be the only clinicopathologic factor determining localization accuracy.

Summary Objective To determine the sensitivity and positive predictive value (PPV) of subtraction scintigraphy (SS) vs. ultrasonography (US) of the neck combined with rapid intact parathyroid hormone (iPTH) assay in US-guided fine-needle parathyroid aspirates in preoperative localization of parathyroid adenomas and in directing surgical approach. Design The results of SS for localization of parathyroid adenoma were determined in 121 patients with primary hyperparathyroidism (pHPT) and compared with findings at surgery and with the results of US alone (in patients without nodular goitre) and US in combination with the iPTH assay in US-guided fine-needle aspirates (FNAs) of suspicious parathyroid lesions (in patients with concomitant nodular goitre). Patients All 121 patients had biochemically documented pHPT; all were referred for first-time surgery. Measurements SS was performed with 99mTc-sestamibi and 99mTc-pertechnetate. High-resolution US of the neck was performed by a single endocrine surgeon and combined with US-guided FNAs of suspicious parathyroid lesions in all patients with nodular goitre (n = 43). Results The sensitivity and PPV of SS were significantly higher in patients without vs. with goitre (89·3% and 95·7%vs. 74·3% and 76·5%, respectively; P

Purpose: To determine and predict P-glycoprotein (Pgp) and multidrug-resistance-related protein (MRP) expression in untreated breast cancer patients by visual and quantitative indices of double-phase 99mTc MIBI scintimammography (DSMM). Patients and Methods: Eighty-two patients with untreated breast cancer received DSMM. Pgp and MRP expression was assessed by immunohistochemical (IHC) staining of surgical specimens. Visual and quantitative analyses were compared with the results of IHC to determine and predict Pgp and MRP. Results: The early and delayed tumor to normal tissue ratio (T/N) of the Pgp-negative and MRP-negative group had significantly higher values than those of the Pgp-positive and MRP-positive group. However, there were no statistically significant differences in washout rate (WR, in %) according to the expression of Pgp and MRP. The optimal T/N ratios were ≤2.23 for early and ≤1.75 for delayed image for Pgp expression and ≤2.45 for early and ≤1.96 for delayed image for MRP expression. The optimal visual grades of DSMM for the determination of Pgp and MRP expression were ≤3. With logistic regression analysis, potent predictors of DSMM were visual assessment for Pgp expression and early T/N for MRP expression. Conclusion: In conclusion, despite a moderate sensitivity and specificity, visual and quantitative indices of DSMM could be used to determine and predict Pgp and MRP expression in untreated breast cancer. However, these findings need confirmation in a larger patient cohort to enable a better validation of Pgp and MRP expression to determine optimal early and delayed T/Ns and to investigate predictors of Pgp and MRP expression in breast cancer.

Background Technetium 99m ( 99m Tc)-methoxyisobutylisonitrile (MIBI) single photon emission computed tomography (SPECT) is frequently used in the evaluation of patients with hyperparathyroidism. Calcium channel blockers (CACBs) may affect 99m Tc-MIBI uptake by parathyroid cells. This study examines the effect of CACB therapy on the sensitivity of 99m Tc-MIBI SPECT localization for hyperparathyroidism. Methods Two hundred fifty-three operated patients with hyperparathyroidism were retrospectively reviewed. The potential effect of CACB therapy on 99m Tc-MIBI scan sensitivity was examined by using logistic regression analysis. Possible confounding factors were considered. Results Among 235 patients, those with multiple endocrine neoplasia, type I (MEN-I), MEN-IIA, 4-gland hyperplasia, secondary hyperparathyroidism, and tertiary hyperparathyroidism exhibited no difference associated with CACB use. Of the remaining 198 patients with primary hyperparathyroidism, 7/30 (23%) with negative 99m Tc-MIBI SPECT scans compared to 24/168 (14%) with positive scans used CACBs. After correcting for age, gender and gland weight, the odds ratio (OR) for a negative study in patients taking CACBs was 2.88 (95% CI, 1.03-8.10; P = .045). Atherosclerosis, hypertension, diabetes mellitus, preoperative calcium and parathyroid hormone levels, and thyroid hormone use were not confounding factors. Conclusions CACB therapy reduces the sensitivity of 99m Tc-MIBI parathyroid SPECT in patients with primary hyperparathyroidism. Further studies are required to determine the potential reversibility of this effect with termination of CACB therapy.

A 24-year-old woman was admitted to our department for further examination of hypercalcemia, a high level of intact parathyroid hormone (PTH) and a right parathyroid tumor. She complained of bone pain throughout her body and was unable to walk due to systemic cystic osteofibrosis, including a brown tumor of the left lower extremities. Neck ultrasonography (US) and magnetic resonance imaging (MRI) revealed a tumor 2 cm in diameter in the upper side of the right thyroid lobe. 99mTc sestamibi (99mTc-MIBI) imaging and F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) were performed to diagnose primary hyperparathyroidism and examination of other parathyroid glands. However, neither imaging modality detected the parathyroid tumor. To confirm the diagnosis, we performed selective venous sampling around the parathyroid and the patient was diagnosed with primary hyperparathyroidism due to a right parathyroid tumor. Resection of the right parathyroid tumor was performed and the pathological diagnosis was parathyroid adenoma. To date, both 99mTc-MIBI and FDG-PET are useful to localize parathyroid tumors. In this case, however, neither modality detected the tumor. Although recent studies state that expression of P-glycoprotein (P-gp) in parathyroid tumors plays an important role in the false-negative results of both 99mTc-MIBI scans and FDG-PET, immunohistological study detected no P-gp expression in the parathyroid tumor in the current case.

OBJECTIVE: To assess the relevance of (99m)Tc-SestaMIBI (MIBI) scan in the diagnostic evaluation of thyroid nodules with oncocytic cytology. SUBJECTS AND METHODS: Twenty-four patients with a single (or prevalent) 'cold' solid nodule with Hurthle cells (HC) at fine needle aspiration cytology (FNAC) were studied. Cytological diagnosis of oncocytic metaplasia (OM) or HC tumor (HCT) was made when HC on the smear were comprised 10-75%, or >75%. Nodules concentrating MIBI at early and late (2 h after washout) stages were considered MIBI-positive. In all cases histological findings were obtained after total thyroidectomy. RESULTS: FNAC was malignant or suspect for malignancy in 16 cases (six HCT and 10 OM) and not suspect in eight (two HCT and six OM). Histological examination revealed 14 malignant tumors (11 HCT and three OM), and 10 benign thyroid lesions (three HCT and seven OM). Sensitivity of FNAC for malignancy was 92.8% and specificity was 70.0%; HCT were identified by FNAC in only 35.7% and OM in 70.0% of cases. No significant difference in MIBI positivity was found between malignant and benign thyroid nodules. The highest percentage of MIBI positivity was found in HCT (78.5%), but MIBI-positive nodules were also observed in thyroid lesions with HC metaplasia (40.0%). CONCLUSIONS: MIBI scintiscan has no value in differentiating malignant from benign HC thyroid neoplasias. Most HCT are MIBI-positive, but this scan is not sufficiently specific to differentiate true HC neoplasias from other thyroid lesions showing HC at FNAC, although an MIBI-negative scan strongly supports the absence of true HCT.

As the mechanism of (99)mTc-MIBI scintimammography is different from that of anatomic modalities, the detection of breast cancer should not be affected by prior breast augmentation. The aim of this study was to compare the diagnostic accuracy of (99)mTc-MIBI scintimammography for breast cancer in patients with or without paraffinomas or siliconomas. Twenty-eight women with a history of paraffin or silicone injection into the breasts and 17 without were included. All patients received intravenous injection of 1110 MBq (99)mTc-MIBI and were subsequently examined using high-resolution planar and SPECT imaging 5 minutes after the injection. In the 45 patients with 87 breasts, 21 abnormal breasts were found at scintigraphy. The sensitivity, specificity, and accuracy to detect cancer in these breasts with paraffinomas or siliconomas were 100% (5/5), 92% (46/50), and 93% (51/55), respectively. For the breasts without paraffinomas or siliconomas, the sensitivity, specificity, and accuracy were 92% (11/12), 95% (19/20), and 94% (30/32), respectively, not significantly different (p = 0.51, 0.66, and 0.86, respectively). (99)mTc-MIBI scintimammography is both sensitive and specific for the detection of breast cancer, whether or not paraffinomas or siliconomas are present. The accuracy of scintimammography did not seem to be affected by prior breast augmentation.

Although sestamibi scanning has been shown to have greater sensitivity and specificity than other preoperative localization techniques for parathyroid adenoma, it is unclear whether preoperative scanning improves outcomes for parathyroid surgery. Data from 528 consecutive patients who underwent neck exploration for primary hyperparathyroidism by one surgeon were collected prospectively over a 5-yr period. Patients were classified by preoperative scanning status (no scan, positive scan, and negative scan), and outcomes were compared in terms of operative time, length of hospital stay, and cure rate. Patients who had undergone a previous parathyroid operation and patients who received alternate preoperative localization techniques (ultrasound, magnetic resonance imaging, and computed tomography) were excluded from the study. All scans were ordered by the referring physician-the surgeon made no recommendations for preoperative scanning. All groups were similar in terms of gender, age, anesthesia class, body habitus, and complication rate. There was no significant difference in cure rate between patients who had preoperative scanning (97.5%) vs. those who did not (99.3%); however, there was a significant difference in cure rate between the negative-scan group (92.7%) and the positive and no-scan groups (99.3%, P0.01). In patients without concomitant thyroid surgery, there was no significant difference in operative time between the no scan (42.4 +/- 14.9 min) vs. the all-scan group (40.2 +/- 15.2 min); however, there was a significant difference between the negative scan group (44.5 +/- 21.9 min) and the positive scan group (38.5 +/- 12.6 min, P0.01). There was no significant difference in length of hospital stay among the three groups. These results suggest that, although preoperative sestamibi scanning does not alter the outcome of parathyroid surgery, it does identify those patients who are less likely to be cured.

Background The purpose of this study is to evaluate the efficacy of scintimammography with 99m Technetium-Sestamibi for the diagnosis of breast cancer. Methods This was a multicenter prospective cohort clinical trial. A total of 1,734 women were enrolled of whom 1,243 had complete data upon study completion. Results The mean ± standard error age of the patients is 56 ±12 years (with a range of 19 to 94). Mammographic results were classified by the Breast Imaging Reporting and Data System (BIRADS) as 199 (16%) BIRADS 5, 149 (12%) BIRADS 4, 199 (16%) BIRADS 3, and 696 (56%) BIRADS 2 or 1. Scintimammography was positive for 322 (26%) of the patients and negative for 921 (76%). Histopathology showed malignancy for 201 (16%) of the patients. Sensitivity and specificity of scintimammography was estimated 93% and 87% respectively. A positive predictive value (PPV) of 58% with a negative predictive value of 98% were calculated. Conclusions The present study suggests that scintimammography with 99m Technetium-Sestamibi is highly accurate for the detection of breast cancer.

A case of deep high energy electrical burn of the skull is presented. For assessment of bone regrowth and muscle flap viability after application of latissimus dorsi free flap, combined 99mTc MDP bone SPECT and 99mTc sestamibi muscle SPECT scintigraphy were used. Whereas 99mTc MDP bone SPECT showed absent uptake at the beginning, there was good uptake 3 months after flap application. 99mTc sestamibi SPECT revealed good uptake indicating normal perfusion of flap muscle tissue.

Background: The advent of highly accurate parathyroid imaging and the ever-increasing trend towards minimally invasive procedures have changed considerably the surgical approach to the patient with primary hyperparathyroidism (PHPT) caused by a single parathyroid adenoma. This study analyzes the short- and longer-term results of 140 patients who underwent minimally invasive, radio-guided parathyroidectomy. Methods: Demographic, clinical, and pre-operative imaging data, operative findings, and short- and long-term results of 140 consecutive patients operated within a 20 months period (8/1999–4/2002), were prospectively entered into a database. Immediate pre-operative sestamibi scintigraphy with skin marking of focal adenoma uptake were followed by intraoperative hand-held gamma probe for the removal of the parathyroid adenoma by unilateral minimal access surgery. Preoperative and surgical data were analyzed and correlated to outcomes, measured by success or failure to cure PHPT, associated morbidity and mortality, predictive value of localizing studies, and postoperative laboratory results in the immediate as well as long-term period. Results: 140 patients, mean age: 55.1 ± 14.1 years (range 19–88 years), female to male ratio 94:46 with PHPT proven by concomitantly elevated serum calcium and parathormone (PTH) levels, with a single adenoma identified by sestamibi single photon emission tomography (SPECT) scintigraphy and high-resolution sonography, underwent minimally invasive, radio-guided parathyroidectomy. Mean serum levels of preoperative calcium, phosphorus, and PTH were 11.6 ± 0.8 mg/dL (range 9.1–14), 3.0 ± 0.3 mg/dL, and 147.1 ± 94.3 pg/mL (range 68–784), respectively. Overall, in 3 out of 140 patients (2.1%), focused, minimally invasive surgery failed to identify and remove the adenoma. Positive predictive value when both localizing modalities concurred was 99.2%. Positive predictive value of SPECT scan alone was 97.2%. Overall success rate was 97.8% (137/140). 24 hours postoperative mean serum calcium was 9.2 ± 0.8 mg/dL and at 6 months mean serum calcium, phosphorus, and PTH were 9.4 ± 1.06 mg/dL, 3.2 ± 0.8 mg/dL, and 32.1 ± 11.9 pg/mL, respectively (p = 0.0001). There was no mortality. In 2 patients (1.4%) there was transient vocal cord paresis and there were 8 instances of clinically significant hypocalcemia. In 3 cases (2.1%), a second adenoma manifested itself 9–14 months following surgery and was removed by minimal access procedure. Conclusions: Minimally invasive, radio-guided focused parathyroidectomy for a single adenoma is safe and effective in curing hyperparathyroidism with a 97% success rate. A second adenoma occurring in less than 3% may be successfully treated with a second minimal access operation. The combined positive predictive value of concurring sestamibi SPECT scintigraphy and sonography of 99.2% may increase success rate, and thus implementing this technique in patients with concurring sonography and scintigraphy may be advocated.

Primary hyperparathyroidism is a benign but sometimes devastating disease. There is concern that the incidence of primary hyperparathyroidism is increasing, with its prevalence approaching 1% in elderly women. 1 Causes include single and double adenomas, multiglandular hyperplasia of a primary and secondary nature, and rarely parathyroid carcinoma. The traditional surgical approach designed to cure patients of this disease has involved careful exploration of the central neck with the intent of first identifying all four parathyroid glands before resecting any glands that appear to be enlarged. To facilitate such a dissection, general endotracheal anesthesia has been necessary. Surgical judgment and expertise have been significant factors, and skilled endocrine surgeons have reported cure rates of 97% to 99% using this approach. 2,3 In the past decade, improvements with parathyroid imaging and the development of a miniaturized hand-held gamma probe have allowed new surgical techniques in the management of patients with primary hyperparathyroidism. Dual-phase technetium-99m sestamibi (MIBI) parathyroid scintigraphy has increased the sensitivity for detecting parathyroid adenoma to 91%, with a specificity of 98.8%. 4 This improvement in parathyroid imaging combined with the development of hand-held gamma probes led to the technique of minimally invasive radioguided parathyroidectomy (MIRP). 5 This procedure, predicated on a positive sestamibi parathyroid scan, allows the surgeon to be guided down to the parathyroid adenoma using the hand-held gamma probe, often without the need for general endotracheal anesthesia. Since the initial report, the technique has been further refined and validated in a large series of patients undergoing initial parathyroid surgery, 6 as well as in patients undergoing reoperative parathyroid surgery. 7 Angelos 8 and Goldstein et al. 9 have also reported the successful application of this technique to patients with primary hyperparathyroidism. In addition to operative success, use of the procedure has resulted in decreased operative time, length of hospital stay, and hospital charges. 4,9 These results support the conclusion that the MIRP procedure can now be considered a standard procedure to be offered to patients with primary hyperparathyroidism. Another development in the past decade that has contributed to an additional choice of procedure for patients with primary hyperparathyroidism has been the quick intraoperative parathyroid hormone assay (iPTH). 10 The current assay can yield a serum parathyroid hormone (PTH) determination in less than 15 minutes. Using the iPTH assay in patients who had successful preoperative localization of a parathyroid adenoma based on a positive parathyroid scan, Irvin et al. 11 and Carty et al. 12 have performed unilateral exploration of the neck with high rates of success. Udelsman et al. used the term “minimally invasive parathyroidectomy” (MIP) for a scan-based unilateral cervical exploration under cervical block using the iPTH determination to confirm the cure. 13 Recently Udelsman reported on results of over 250 MIPs, with a 99% cure rate. 14 Flynn et al. 15 combined the MIRP technique with the iPTH assay and reported excellent results in a small series of patients. The purpose of the current study was to evaluate the results of a large series of MIRPs in which iPTH was not routinely used, and to investigate characteristics between patients who had positive scans and thus were candidates for a MIRP versus those with negative scans.

Background: Septal perfusion defects are common on my-ocardial perfusion single-photon emission computed tomography (SPECT) slices in patients with left bundle-branch block (LBBB) in the absence of coronary artery disease. Hypothesis: The use of gated myocardial perfusion SPECT imaging in such patients should be clinically validated. The aims of this study were, therefore, to validate clinically the use of gated myocardial SPECT imaging to avoid false positive septal perfusion defects in patients with LBBB and to compare nongated and gated SPECT imaging techniques in the same patients in the same imaging session. Methods: We performed stress-rest myocardial perfusion SPECT and resting gated SPECT using Technetium-99m MIBI in 25 patients with LBBB and in 6 control subjects. Stress-rest SPECT images and end-diastolic and end-systolic gated SPECT slices were assessed visually and quantitatively (septum/lateral wall count ratio). Coronary angiography was performed in 15 patients with LBBB and in all 6 control subjects. Results: Stress-rest (nongated) SPECT slices and end-diastolic and end-systolic gated SPECT images were normal in all control subjects. Stress-rest (nongated) SPECT imaging revealed septal perfusion defect in 20 (11 reversible, 9 irreversible) patients with LBBB, whereas the figures were 15 and 5 for end-systolic and end-diastolic gated SPECT images, respectively. Coronary angiography results were normal in all control subjects and in 15 patients with LBBB. Quantitative analysis of gated SPECT images revealed no statistically significant difference between patients with LBBB and control subjects in end-diastolic mean septum/lateral wall count values (0.86 ± 0.19 in LBBB vs. 0.98 ± 0.15 in normal subjects, p > 0.05), but the difference was statistically significant for end-systolic, stress, and rest values (p < 0.001 for all). Conclusion: Gated SPECT imaging, particularly end-diastolic images, revealed fewer false positive results and thus can be used to avoid false positive septal perfusion defects commonly seen in stress-rest (nongated) myocardial perfusion SPECT in patients with LBBB.

Purpose The purpose of this study was to determine the value of the intraoperative gamma probe and the efficacy of dual-phase Tc-99m sestamibi imaging in patients with primary hyperparathyroidism. Methods Twenty-one patients with primary hyperparathyroidism were examined prospectively. Results of same-day dual-phase Tc-99m sestamibi scintigraphy and intraoperative gamma probe evaluations were compared with the intraoperative findings and histopathologic diagnoses. A 15-mm handheld gamma probe was used to measure gamma activity in the neck and upper mediastinum. Nuclear mapping by gamma probe showed a single quadrant of neck that emitted gamma radiation significantly greater than the other three quadrants, which correlated with the sestamibi scan. Results Dual-phase Tc-99m sestamibi scintigraphy determined and localized parathyroid lesions in 20 patients (sensitivity, 94%). Of the 20 parathyroid lesions removed, 15 were located in normal positions, whereas five were explored in ectopic sites (one within the thyroid, one in the anterior mediastinum, one in a retrotracheal position, one in the carotid sheath, and one in the retroesophageal region). Although the index of thyroid nodules varied from 15.8% to 22.9%, the index for parathyroid lesions was 77.3% to 112.8%. Conclusions These results confirm that parathyroid lesions, especially at ectopic sites, can be treated successfully in shorter operative times with minimal complications with the help of the intraoperative gamma probe.

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%. 1–3 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.

The percentage of myeloma cells in bone marrow is subsequently an important index of disease in patients with multiple myeloma (MM). Bone marrow myeloma cells can be detected by strong CD38/CD138 positivity and light scatter characteristics using flow cytometry. The aim of the study was to evaluate the relationship between the degree of Tc-99m methoxyisobutylisonitrile (MIBI) uptake and the percentage of CD38/CD138 expressing myeloma cells in the bone marrow of patients with MM. A total of 15 patients with MM (mean age: 61.7+/-2.4 years; 7 F and 8 M) were included in the study. Tc-99m MIBI imaging was obtained 20 min after injection of 740 MBq Tc-99m MIBI. Planar spot images of the pelvis and thorax were acquired. The uptake of Tc-99m MIBI in the bone marrow was evaluated using a qualitative and also a semiquantitative scoring system for the bone marrow in areas that included the proximal femurs, anterior iliac crest, and sternum. In all patients, flow cytometry was performed for assessing the percentage of CD38/CD138 expressing myeloma cells in the bone marrow samples. There was a statistically significant positive correlation between the percentage of CD38/CD138 expressing plasma cells in bone marrow and both mean qualitative (r=0.689, p=0.005) and semiquantitative (r=0.669, p=0.006) results of Tc-99m MIBI uptake. In conclusion, our results indicate that increased Tc-99m MIBI uptake of bone marrow is related to the percentage of plasma cell infiltration of bone marrow. Tc-99m MIBI bone marrow imaging may be a useful tool for predicting the levels of myeloma cells in bone marrow of patients with MM.

Several years ago technetium-99m tetrofosmin was reported to localise parathyroid adenomas. The aim of this study was to compare the sensitivity of this radiopharmaceutical with that of (99m)Tc-sestamibi using a double-phase parathyroid scintigraphy protocol. Scans of 12 patients were evaluated visually and lesion to thyroid ratios were calculated. Nine of the patients were subsequently operated on; a total of eight parathyroid adenomas or hyperplastic glands were histologically confirmed in seven of the patients, while in one patient a parathyroid carcinoma was histologically proven. All of these patients had positive (99m)Tc-sestamibi scintigrams, whereas only two (99m)Tc-tetrofosmin scintigrams were positive. With (99m)Tc-sestamibi there was a significant increase in the lesion to thyroid ratio from 10 min to 90 min and 150 min p.i. which was not seen on scintigraphy with (99m)Tc-tetrofosmin. This makes (99m)Tc-tetrofosmin less suitable for double-phase parathyroid scintigraphy.

Following an acute myocardial infarction, the size of the infarct and the resulting left ventricular volume and function are important predictors of mortality. Identifying patients with impaired tissue level perfusion after percutaneous coronary intervention (PCI) for myocardial infarction therefore could have prognostic implications. To obtain combined measures of left ventricular perfusion, volumes and function we applied a gated myocardial perfusion imaging by 99mTc-sestamibi single photon emission computerized tomography to 19 patients immediately after revascularization by PCI and repeated this after 3 months. The results of the acute myocardial perfusion imaging significantly correlated to final infarct size, left ventricular volumes and function 3 months later. It is concluded that the method holds the potential for risk stratifying patients immediately after revascularization for acute myocardial infarction.

The aim of the present study was to examine whether Doppler tissue imaging demonstrated comparable diagnostic performance for the detection of viable myocardium compared to myocardial perfusion imaging with 99m Tc hexakis-2-methoxyisobutylisonitrile (MIBI). We studied 30 patients with old myocardial infarction who underwent percutaneous transluminal coronary angioplasty (PTCA). Myocardial single photon emission computed tomography (SPECT) with 99m Tc-MIBI and two-dimensional echocardiography were carried out within 7 days before PTCA. We measured regional 99m Tc-MIBI uptake for each myocardial segment from SPECT and peak systolic velocity and a ratio of regional pre-ejection period to regional ejection time (PEP/ET) from pulsed Doppler tissue imaging. Biplane left ventriculography was performed before interventional procedures and repeated 3 months after PTCA. Myocardial viability was determined when wall motion was improved at least one grade after PTCA. The peak systolic velocity was positively correlated with regional 99m Tc-MIBI uptake (R =0.59, P

Technetium-99m sestamibi imaging for parathyroid adenoma localization has been performed using both dual-tracer subtraction and double-phase single-tracer washout techniques. The relative accuracy of these two techniques is uncertain. We have developed a modified imaging technique which combines both approaches and have directly compared them in a series of patients with surgically explored hyperparathyroidism. Initial injection of (99m)Tc-pertechnetate 50 MBq was followed by continuous dynamic imaging of the anterior neck for 30 min. (99m)Tc-sestamibi 1,000 MBq was injected intravenously at the midpoint of the acquisition. Delayed images were performed after 2 h. We blindly reviewed 88 consecutive cases of surgically explored hyperparathyroidism that had undergone preoperative scintigraphic localization with this procedure. Images were reformatted to display subtraction-only, early/delayed sestamibi-only and combined images. Scans were reviewed in random order. Of the 68 cases with solitary parathyroid adenoma, the sestamibi-only images gave correct localization in 49 (72%) while there was a statistically significant improvement in accuracy using the subtraction-only images (58 of 68, 85%, P=0.05) and the combined images (61 of 68, 90%, P=0.0015). Reader confidence was also greater with the subtraction-only and combined images than with the sestamibi-only images. Scan performance with parathyroid hyperplasia was less satisfactory. Although the largest gland was usually correctly identified, hyperplasia was difficult to distinguish from a solitary adenoma. Dual-tracer subtraction parathyroid imaging is superior to double-phase sestamibi-only imaging. The washout data may provide additional information in some cases, however, and an approach that combines both techniques may be optimal.

A parathyroid tumor is not larger than other tumors, so minimally invasive surgery has long been a major focus of parathyroid surgeons. Improving endoscopic instruments has facilitated the recent changes in approaches to parathyroid surgery. Endoscopic parathyroidectomy is developed in a totally closed space with CO2 gas insufflation. This method has a risk of complications, such as extensive emphysema or hypercarbia. Minimally invasive video-assisted parathyroidectomy (MIVAP) has greater safety, low cost, easy procedure and flexibility in changing the working space including conversion to open method when compared with endoscopic parathyroidectomy. MIVAP can be performed with only a 1-1.5-cm small incision on the neck. MIVAP is indicated in the patient with parathyroid adenoma or renal hyperplasia that is defined preoperatively using ultrasonography and 99mTc-methoxyisobutylisonitrile (MIBI) scan. Furthermore, the radio-guided technique using nuclear navigation after preoperative administered MIBI is being developed. This method is so useful during MIVAP that we combined MIVAP and radio-guided surgery to develop minimally invasive radio-guided and video-assisted parathyroidectomy (MIRVAP). After injection of 600 MBq of MIBI, intraoperative nuclear mapping was performed using a hand-held gamma probe. Then we expected to find swollen parathyroid tumor at surgery when radioactivity at a level relatively higher than background was found. Following this mapping result, MIVAP was started and succeeded. The radio-guided technique is also indicated for open parathyroidectomy (radio-guided open parathyroidectomy, RGOP) in multiglandular disease (MGD) when it was not possible to identify those lesions completely, for instance in asymmetric hyperplasia, such as multiple endocrine neoplasia (MEN) 1. In conclusion, MIVAP is beneficial for minimal invasiveness and cosmesis. Furthermore, radio-guided parathyroidectomy (MIRVAP and RGOP) is more useful and feasible. Improvement of endoscopic instruments and modification of the dose of MIBI administered might facilitate treating more cases by MIRVAP instead of RGOP.

Intraoperative quick parathyroid hormone (QPTH) assay is claimed to prevent failure during parathyroidectomy for hyperparathyroidism. The causes of operative failure have included multiglandular disease, ectopic parathyroid glands, supernumerary parathyroid glands, errors in frozen section evaluations, and missed diagnosis. A QPTH assay has been recognized as a useful method of determining whether hyperfunctioning tissues have been completely excised. However, an intraoperative QPTH assay may fail to detect the presence of double parathyroid adenomas. Use of this assay in conjunction with preoperative and intraoperative localization studies has led to the advocacy of more directed cervical procedures, such as limited, video-assisted, and endoscopic parathyroidectomy.

Complete surgical resection of hyperfunctioning parathyroid tissue is essential for the curative treatment of hyperparathyroidism. It is very important to identify the accurate location of the affected parathyroid glands by imaging tests to successfully achieve this surgical treatment. Tc-99m labeled sestamibi is a radiopharmaceutical with high affinity for endocrinologically active parathyroid tissue, and scintigraphic evaluation using this radioactive agent is very useful in confirming the location of the affected parathyroid glands. The recent remarkable development of hand-held gamma-ray detectors makes it easy to perform radio-guided surgery, which is a combination of a preoperative intravenous injection of sestamibi and intraoperative navigation by the gamma-rays radiating from the pathological sites. This strategy can be easily applied to the resection of the ectopically located gland and is also useful to confirm the absence of endocrinologically active tissue after the operation. Additional chest SPECT imaging might be effective in the risk assessment of cardiac incidence in the perioperative period, as sestamibi was originally developed for the evaluation of myocardial perfusion. In conclusion, Tc-99m sestamibi will be more popularly applied to the treatment of hyperparathyroidism as minimally invasive surgery increases in favor.

During parathyroidectomy (PTx) for primary hyperparathyroidism (PHP), we surgically explored the contralateral parathyroid glands as well as those whose localization was clarified by ultrasonography and parathyroid scintigraphy. Although it is important to explore the contralateral side and other glands, we frequently treat only the gland whose localization is confirmed. Recently, we have performed minimally invasive radioguided parathyroidectomy (MIRP) that resects only one gland observed on the imaging under technetium 99m-labeled sestamibi (MIBI) scanning guidance after obtaining prior informed consent. In this surgery, even if recurrence is observed contralaterally, it is possible to apply a similar procedure to the contralateral side again. We examined six PHP patients who underwent MIRP and two PHP patients treated with percutaneous ethanol injection therapy (PEIT). The follow-up period was 2 years. PEIT was selected as a treatment method for two patients based on the patients’ characteristics. When only one gland is treated, the efficacy of PEIT was considered to be similar to that of MIRP.

Coronary artery disease (CAD) is the leading cause of morbidity and mortality in diabetics. Early diagnosis of CAD and identification of high-risk subgroups, followed by appropriate therapy, may therefore enhance survival. This study sought to determine the value of stress myocardial perfusion single-photon emission computed tomography (SPECT) with technetium-99m sestamibi to detect perfusion defects and predict cardiac events in asymptomatic diabetics. One hundred eighty asymptomatic diabetics without known CAD who underwent 2-day stress technetium-99m sestamibi SPECT were followed up for 36 +/- 18 months. End points were defined as hard (myocardial infarction or cardiac death) or total events (myocardial infarction, cardiac death, or late revascularization). Logistic regression analysis evaluated clinical variables, type of stress, exercise treadmill test (ETT), and SPECT as predictors of end points. Perfusion defects were found in 26% of patients (15% reversible, 6% mixed, and 5% fixed). Clinical or ETT variables were not associated with perfusion defect type or with hard events. However, male gender predicted total events (chi-square 3.3; p = 0.01). An abnormal SPECT significantly increased the risk of hard events (chi-square 5.4; p = 0.001) and total events (chi-square 7.4; p = 0.0001). Extensive defects determined the highest risk of total events (chi-square 18.8; p = 0.0001). Event rates increased according to SPECT: 2% of hard events per year and 5% of total events per year in patients with normal SPECT versus 9% per year and 38% per year, respectively, in those with abnormal SPECT. Importantly, a normal SPECT identified a relatively low-risk subgroup of patients. Thus, stress technetium-99m sestamibi SPECT was useful in evaluating asymptomatic diabetics for the presence of CAD, and effectively risk-stratified this population.

Resistance to doxorubicin based chemotherapy is a major therapeutic problem limiting advanced breast cancer treatment. 99mTc hexakis-2-methoxyisobutylisonitrile ((99m)Tc-MIBI) has been reported to be extruded from tumour cells by the P-glycoprotein and multidrug resistance protein encoded by MDR1 and MRP1 genes, respectively. These proteins are involved in the cellular efflux of several chemotherapeutic agents including doxorubicin. The aim of this study was to investigate the clinical value of a standard (99m)Tc-MIBI scintimammography technique in the prediction of response to chemotherapy in advanced breast cancer patients. Fifty-six lesions from 33 female patients with locally advanced (n=27) or recurrent breast cancer (n=6) were included in the study. MIBI scintigraphy was performed 2-8 days prior to chemotherapy (FAC regimen). Images were acquired 10 min and 1 h post-injection of 740-1110 MBq of (99m)Tc-MIBI. Tumour-to-normal background tissue uptake ratios were calculated on each lesion in the early (T/B(e)) and delayed phase of the study (T/B(d)). Both T/B(e) and T/B(d) ratios were significantly higher (P0.0001) in responders (n=43) than nonresponders (n=13). Diagnostic values of (99m)Tc-MIBI in the prediction of chemotherapy response were evaluated using the arbitrary cut-off values of 1.5 for T/B(e) and 1.4 forT/B(d). Sensitivity, specificity, positive and negative predictive values were 88.4%, 92.3%, 97.4%, 70.6%; and 90.7%, 100.0%, 100.0%, 76.6%, for T/B(e) and T/B(d), respectively. We conclude that (99m)Tc-MIBI scintigraphy may be a clinically valuable tool for guiding chemotherapy in advanced breast cancer patients.

A dual-isotope simultaneous acquisition (DISA) single-photon emission tomography (SPET) protocol with fluorine-18 fluorodeoxyglucose ((18)F-FDG) and a technetium-99m labelled flow tracer is attractive because it permits assessment of both myocardial glucose utilisation and flow within a single study. Differences in physical and physiological characteristics between (18)F-FDG and the (99m)Tc-labelled flow tracer, however, may cause differences in myocardial activity distribution between the agents. The aim of this study was to investigate the relation between the myocardial distribution of (18)F-FDG and a (99m)Tc-labelled flow tracer on DISA SPET in comparison with nitrogen-13 ammonia/(18)F-FDG positron emission tomography (PET). Nine normal volunteers without cardiac disease and ten patients with known coronary artery disease (CAD) underwent (13)N-ammonia/(18)F-FDG PET and (99m)Tc-sestamibi/(18)F-FDG DISA SPET. Using a semiquantitative polar map approach, the left ventricular myocardium was divided into nine segments, and relative regional activity was calculated for each segment. A segment was considered to have concordant uptake between (18)F-FDG and flow tracer if the difference in measured regional activity between the tracers wasor =10% of peak activity, and the percentage of concordant segments was calculated for each subject. There was a good overall concordance of myocardial activity between the agents on DISA SPET (84.0%+/-14.8%) in normals, which was comparable to that seen on PET (86.4%+/-14.5%, NS vs DISA SPET). However, the myocardial activity distributions of (18)F-FDG and flow tracer were not identical in that reduced flow tracer activity was seen in the basal segments on DISA SPET in both normals and CAD patients. It is concluded that there is good overall concordance of activity between (18)F-FDG and flow tracer in normal myocardium on DISA SPET, which is comparable to that on PET, supporting the use of combined (99m)Tc-flow tracer/(18)F-FDG imaging for the detection of viable myocardium. However, there is a difference in the myocardial activity distribution between the agents in both normals and CAD patients, the difference being particularly evident in the basal segments. Therefore, careful image interpretation that takes into consideration the different normal activity distribution between the tracers and/or a tracer-specific normal database is necessary for comparison with patient studies.

Purpose No imaging technique has been found to be adequate to assess the severity and extent of bone involvement in patients with Gaucher disease. Marrow involvement, as determined by Tc-99m sulfur colloid, correlated well with the clinical and radiologic changes of the skeleton, but a normal pattern was found in the early stages of the disease. Subsequently, Tc-99m sestamibi (MIBI) has been suggested for direct visualization of glycolipid deposits in the bone marrow. This study was initiated as a pilot using MIBI to detect various forms of bone disease in patients with Gaucher disease of varying severity. Materials and methods Eleven patients (9 men; median age, 39.9; age range, 21 to 61 years) were evaluated. The clinical severity of disease was scored at presentation, and four patients with moderate to severe disease were treated with enzyme replacement therapy. Each patient underwent a radiographic skeletal survey, bone densitometry, and MIBI scintigraphy. The scan included static images of the lower limbs, with a whole-body scan acquired between the early and late acquisition. Tracer uptake in the bone marrow was graded and correlated with clinical and objective variables. Results All but one patient had increased MIBI uptake in the bone marrow. No correlation was noted between MIBI uptake and severity score, radiographic changes, densitometry z score, or treatment status. Conclusions MIBI scanning is a sensitive technique for detecting bone marrow deposits in Gaucher disease, but it is inadequate for early identification of patients at high risk for skeletal complications or for the follow-up of patients treated with enzyme replacement.

BACKGROUND: Technetium 99m-sestamibi imaging might be the best method to localize abnormal parathyroid glands. No studies to date have compared preoperative imaging and intraoperative gamma probe localization in patients with primary hyperparathyroidism. STUDY DESIGN: This prospective study included 20 arbitrarily selected patients with primary hyperparathyroidism, verified by elevated serum ionized calcium and intact parathyroid hormone concentrations and low serum phosphatase level. Each patient underwent both preoperative imaging study of the parathyroid glands with technetium 99m-sestamibi (dose 740 MBq) and intraoperative localization with a handheld gamma probe. Full collar exploration served as the gold standard. RESULTS: Hypercalcemia and hypophosphatemia normalized in each patient. A single parathyroid adenoma was confirmed histologically in 16 and hyperplasia (4 abnormal glands) in 4 patients. None of the patients had multiple adenomas. The sensitivity of the preoperative scan was 81% (13 of 16 patients) in adenoma patients and 100% (4 of 4 patients) in hyperplasia. The corresponding specificity was 88% and 100%. Intraoperatively only 8 of 16 adenomas were correctly detected (sensitivity 50%), and none of the hyperplastic glands were correctly detected. CONCLUSIONS: In unselected patients with primary hyperparathyroidism, preoperative technetium 99m-sestamibi imaging is more accurate than intraoperative gamma probe detection in localizing abnormal parathyroid glands.

Breast cancer remains one of the most common cancers in the developed world. New treatments are proving effective against both limited disease and metastases. Nuclear medicine is in a unique position as it is one of the only methods used to image the breast which is linked to cell cycle changes, the receptors on the cell surface and the cells' response to chemotherapy. Nuclear medicine is unaffected by the anatomical changes seen post-chemotherapy and radiotherapy and is uniquely placed to become a major methodology in the continued assessment of the breast cancer patient. However, before this can happen the utility of nuclear medicine techniques must be proved in multi-centre trials.

Bombesin-like peptides are neurotransmitters and cancer growth factors. Several tumors, breast cancer among them, show one or more than one of the three known bombesin receptors. We have synthesized and labeled with technetium 99m a new pentadecapeptide, analogue to the leu13 amphibian bombesin (99mTc BN). Labeling yield was 83 +/- 4%. Prone Scintimammography was performed on five patients affected by breast cancers (T categorization: two T1b and three T1c), after injecting 0.7 mg, 185 to 296 MBq (5 to 8 mCi) of the peptide. Total body scan did not show free technetium biodistribution. No adverse reaction was observed. Prone Scintimammography with 99mTc Sestamibi (99mTc SM) was also performed few days later. 99mTc BN detected all 5 cancers, whereas 99mTc SM only four: all the T1c and one T1b cancer. Two of them showed axillary node invasion that was detected by both the radiotracers. A fibroadenoma present on contralateral breast to the one with cancer, was not detected neither by 99mTc SM nor by 99mTc BN. Tumor/breast normal tissue ratio (T/B) was constantly higher with 99mTc BN than with 99mTc SM. Maximal T/B was measured as 1.79 with 99mTc SM and 2.25 with 99mTc BN 5 min after fast i.v. administration. In conclusion our 99mTc BN is taken up by primary breast cancer showing higher T/B than 99mTc SM (p0.01). In our limited scale, 99mTc BN appears to be safe and, in our limited scale, even more accurate than 99mTc SM for detecting breast cancer.

Summary Technetium 99m-2-methoxyisobutil-isonitrile (Tc-99m-MIBI), also called sestaMIBI,has been used successfully to detect malignant tumours at diagnosis. Recently, it hasbeen proposed as a safe and effective tracer in patients with multiple myeloma (MM).The purpose of this study was to demonstrate the value of the Tc-99m-MIBI uptakein disease detection and to assess the correlation between the uptake of this scin-tigraphy agent and prognostic factors in newly diagnosed MM patients. Thirty-fiveuntreated patients were enrolled in the study. Tc-99m-MIBI scanning was performedin 33 patients after intravenous injection of 7.4 MBq/kg. Whole-body anterior andposterior scans were obtained after 30 min, 60 min, 2 and 4 h. The correlationbetween known prognostic factors of MM and the intensity of Tc-99m-MIBI uptakewas assessed. Our results showed seven patients with an intensity score of I0, 12patients with I1, eight patients with I2 and six patients with a score of I3. Therewas a positive correlation between Tc-99m-MIBI intensity and C-reactive protein(CRP; r ¼ 0.506, P < 0.01), erythrocyte sedimentation rate (ESR; r ¼ 0.368,P < 0.05), b2- microglobulin (b2M; r ¼ 0.749, P < 0.001), interleukin-6 (IL-6;r ¼ 0.823, P < 0.001), soluble Interleukin-6 receptor (sIL-6r; r ¼ 0.806,P < 0.001), serum calcium (r ¼ 0.578, P < 0.001) and bone alkaline phosphatase(BAP; r ¼ 0.472, P < 0.01). An inverse correlation was found between Tc-99m-MIBI intensity and osteocalcin (OC) and type I procollagen carboxyterminalpropeptide (PICP). In conclusion, the results of this study suggest that moreextensive disease activity, as determined by high levels of CRP, b2M, IL-6 and sIL-6rcorrelated with a higher uptake of the radiotracer.Keywords Cytokines, multiple myeloma, technetium-99m-sestaMIBIIntroduction

With an incidence of more than 180,000 cases per year, breast cancer is the second leading cause of cancer deaths among women in the United States. The wi-despread implementation of screening mammography has resulted in earlier detection of breast cancer, reducing both the morbidity and mortality of the disease. Several large-scale controlled trials have shown that screening mammography is efficacious and can reduce breast cancer mortality by 18% to 30% [1,2]. Conventional screening mammography consists of screen-film images. Screen-film mammography (SFM) fails to detect 10% to 20% of palpable breast cancers, particularly in the dense breast where there is insufficient contrast difference between normal and cancerous tissues [3,4]. Furthermore, the positive predictive value of SFM for cancer is less than 50% (range of 5% to 40%) [5,6], so more than half of the biopsies performed result in benign diagnoses. Even if a biopsy is not performed, excessive recall imaging decreases the cost-effectiveness of screening mammography and increases patient anxiety. This article is devoted to three new modalities in breast cancer screening. It focuses on digital mammography (DM), which has received much attention and interest within both the radiology community and the general public. This chapter also examines the roles of positron emission tomography (PET) and sestamibi scintimammography in breast cancer screening and breast imaging. Digital mammography

Gated single-photon emission computed tomography (SPECT) imaging allows analysis of myocardial perfusion and assessment of baseline global and regional left ventricular (LV) function and their changes during low-dose dobutamine infusion. The study examined whether the changes in LV ejection fraction induced by dobutamine and evaluated using technetium-99m sestamibi- gated SPECT predict the evolution of ejection fraction after revascularization in patients with ischemic cardiomyopathy. Thirty-seven patients underwent resting and dobutamine nitrate-enhanced sestamibi-gated SPECT before revascularization and baseline-resting sestamibi gated SPECT after intervention to assess global functional changes. A postrevascularization improvement in ejection fractionor =5 U was defined as significant. At follow-up, ejection fraction increased significantly in 19 patients. According to receiver-operating characteristic curve analysis, an increase in ejection fractionor =5 U during dobutamine was the optimal cutoff value for predicting a significant postrevascularization improvement, with 79% sensitivity, 78% specificity, and 78% accuracy. A significant correlation was found between dobutamine and postrevascularization ejection fraction (r = 0.85; p0.0001). The increase in ejection fraction during dobutamine is a good predictor of an improvement in ejection fraction after revascularization. This represents another important diagnostic contribution obtained using gated SPECT imaging for the assessment of myocardial viability in patients with ischemic cardiomyopathy.

ObjectivesWe sought to determine the level of angiographic stenosis at which reversible regional wall motion abnormalities (RWMA) are present on exercise stress technetium-99m (Tc-99m)– gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and whether assessments of stress and rest RWMA add incremental diagnostic information.BackgroundStress and rest gated SPECT MPI enables the detection of post-exercise stunning. Although some studies have correlated RWMA to the severity of MPI defects, only one previous study correlated RWMA on gated MPI to angiographic findings. However, this correlation excluded patients with rest perfusion defects and did not involve gating of rest images.MethodsOne hundred patients undergoing angiography within six months of exercise stress Tc-99m (sestamibi)–gated SPECT MPI (in the absence of interim cardiac events or revascularization) were recruited. Images were acquired 15 to 30 min after stress and interpreted without knowledge of the Duke treadmill score, left ventricular ejection fraction and angiographic data.ResultsThe sensitivity of reversibleRWMA for angiographic stenoses >70% was 53%, with a specificity of 100%. The presence of reversible RWMA was able to stratify patients with angiographic stenoses of 50% to 79% and 80% to 99% with a high positive predictive value. A good correlation was noted between the presence of reversible RWMA and the coronary artery jeopardy score (R = 0.49, p < 0.0001). Multivariate analysis showed that the post-stress RWMA, Duke treadmill and reversible RWMA scores were significant predictors of angiographic severity.ConclusionsPost-stress and reversible RWMA, as shown by exercise stress Tc-99m–gated SPECT MPI, are significant predictors of angiographic disease and add incremental value to MPI for the assessment of angiographic severity.

SUMMARY: Percutaneous transluminal coronary angioplasty provides an excellent opportunity to investigate the location and quantity of hypoperfusion during sudden complete occlusion of one of the major coronary arteries. Thirty-five patients referred for elective percutaneous transluminal coronary angioplasty were injected intravenously with 99mTc-sestamibi during balloon inflation. To visualize and quantify the hypoperfused region, a map of perfusion was constructed from that occlusion study and from the control study performed on the following day. Patients were divided into groups according to proximal or distal occlusion within each of the three coronary arteries. The region of myocardium supplied by each coronary artery varied in location and extended outside the typical borders for all arteries, but most prominently for the left circumflex coronary artery. The quantities of hypoperfusion varied within each artery group, but the average hypoperfusion was greater for the left anterior descending coronary artery than for either the right coronary artery or the left circumflex coronary artery. It is concluded that the quantities of hypoperfusion were highly variable within each artery group. Occlusion of the left anterior descending coronary artery was associated with the largest ischaemic region. The area of hypoperfusion extended outside the typical borders, most prominently for the left circumflex coronary artery. (Less)

Objectives We sought to demonstrate the safety of stress-only perfusion imaging among patients with low to medium probability of coronary disease being evaluated for chest pain. Background The need for performing rest in addition to stress perfusion imaging to confirm normalcy is due largely to defects created on the stress images by attenuation artifacts. A low cardiac event rate among patients undergoing stress-only imaging with attenuation correction (AC) would validate the safety of stress-only imaging. Methods Patients with low to medium pretest probability for coronary artery disease (CAD) referred for chest pain evaluation from July 1, 1997 to July 1, 1999, were scheduled for a two-day stress/rest tomographic (single photon emission computerized tomography, or SPECT) perfusion imaging study with Tc-99m sestamibi. Patients were imaged on a variable angle camera with AC using Gd-153 scanning line sources (Vantage ADAC, Milpitas, California). If the stress scan was normal without AC or corrected with AC, the patient did not return for rest scan and was followed. Results Seven hundred twenty-nine patients underwent stress-only imaging, and follow-up was obtained on 652 (89%) of those patients. There were 224 males and 428 females with mean age of 52 ± 13 years. Mean follow-up was 22.3 ± 6.4 months. The mean pretest probability was 37 ± 24%. The non-AC images showed breast and/or diaphragmatic attenuation artifacts severe enough to have required the patient to return for rest imaging in 37% of patients, and all corrected completely with AC. During follow-up, there were two noncardiac deaths and no cardiac deaths. There was one myocardial infarction; three patients with progressive unstable angina underwent diagnostic coronary angiography showing significant CAD. The overall cardiac event rate was 0.6%. Conclusions These results support stress-only imaging in patients with low to medium probability for CAD as a safe, time- and cost-efficient imaging modality.

The purpose of this investigation was to compare the efficiency of two different imaging protocols using two different clinically available 99mTc labelled myocardial perfusion tracers. One thousand one hundred and thirty-four imaging studies were performed prospectively, using either 99mTc-tetrofosmin or 99mTc-sestamibi, alternating the use of each tracer for a total period of 8 months. 99mTc-tetrofosmin rest studies were performed with injections of 259MBq-370MBq and imaging 30 min later. Exercise studies were performed with injections of 777MBq-1.11GBq and imaging 20 min later. 99mTc-sestamibi studies used doses similar to those in the 99mTc-tetrofosmin studies. Imaging followed a standard procedure, at 60 min after rest injection, and 30 min after exercise. For patients undergoing pharmacological stress testing99mTc-sestamibi was imaged 45 min after injection and 99mTc-tetrofosmin was imaged 30 min after injection. Variables analysed were (1) injection-to-imaging time for the procedure, and (2) the number of repeated scans because of extra cardiac activity. The completion time for the rest study was significantly shorter for 99mTc-tetrofosmin compared to 99mTc-sestamibi (47.7+/-21.7 min vs 74.3+/-25.8 min P

Aim: The aim of this study was to evaluate if Tc99m-sestamibi scintimammography in addition to the triple assessment consisting of clinical examination, mammography, breast ultrasonography and fine needle aspiration cytology (FNA) enhances the diagnosis of breast cancer and helps in avoiding unnecessary operative biopsies. Methods: Pre-operational scintimammography was performed within 2 weeks of operation to 46 consecutive patients with abnormal findings in clinical breast examination, mammography or ultrasonography. Three patients had abnormalities in both breasts. Histological diagnosis was obtained in all 49 cases. Results: The histological diagnosis was benign in 18 (37%) cases and malignant in 31 (63%) cases. The overall sensitivity of scintimammography was 77% and the specificity was 61%. The sensitivity of scintimammography was 95% in invasive ductal carcinoma, 50% in invasive lobular carcinoma and 25% in ductal carcinoma in situ. Scintimammography showed 100% sensitivity in cases with invasive carcinoma, with highly suspicious findings for malignancy in the other examinations. The sensitivity was 63% in cases with indeterminate or contradictory findings in mammography, ultrasonography and FNA. Conclusions: Adding scintimammography to the triple assessment does not seem to be helpful in the diagnosis of breast abnormalities because of low sensitivity in malignant cases with a challenging diagnosis by mammography, ultrasonography and FNA, and because of low overall specificity.

Delayed technetium-99m sestamibi single photon emission computed tomography (SPECT) scans were prospectively analyzed in a large series of patients with primary hyperparathyroidism.Three hundred thirty-eight patients underwent sestamibi-SPECT and were explored. Prospective data included preoperative demographics, clinical, sestamibi, and operative findings, laboratory values, and pathologic and follow-up laboratory results from all patients.Between 1994 and 2000, 287 unexplored patients (85%) and 51 re-explored patients (15%) participated. The abnormal parathyroid glands excised from 336 of 338 patients included 299 single adenomas (88%) and 23 double adenomas (7%), and 14 patients had multigland hyperplasia (4%). Sestamibi SPECT correctly lateralized 349 of 400 abnormal parathyroid glands, with an overall sensitivity of 87%, an accuracy of 94%, and a positive predictive value of 86%. Precise localization occurred in 82% of the abnormal parathyroid glands. Sestamibi sensitivity was similar in unexplored (87%) and reoperative (92%) cases; two hundred eighty-six of 299 (96%) solitary adenomas, 38 of 46 (83%) double adenomas, but only 25 of 55 (45%) hyperplastic glands were identified. The mean weight of the true-positive glands (1252 +/- 1980 mg) was greater than that of the false-negative glands (297 +/- 286 mg) (P.005). Three patients had persistent primary hyperparathyroidism, in spite of the excision of sestamibi-identified lesions in 2 cases. Follow-up indicated curative resection in 99% of the unexplored cases and 94% of the remedial cases.Sestamibi SPECT is highly accurate for the localization of parathyroid adenomas in unexplored and re-explored cases, where it is often the only imaging required. Its sensitivity is limited in multiglandular disease.

MS-209 is a newly synthesised multidrug-resistance (MDR)-reversing agent with few side-effects. In this study, we evaluated the effect of MS-209 on P-glycoprotein (Pgp)-positive tumours in mice by means of technetium-99m methoxyisobutylisonitrile (MIBI) imaging. Mice received Pgp-negative KB-3-1 or Pgp-positive KB-C1 cell xenografts. KB-3-1-bearing mice were administered 0 or 100 mg/kg of MS-209 (groups S0 and S100, respectively), and KB-C1-bearing mice 0, 50, 100 or 200 mg/kg (groups R0, R50, R100 and R200, respectively), 30 min before imaging studies. Dynamic 99mTc-MIBI images were acquired for 30 min, followed by biodistribution studies. Washout of 99mTc-MIBI from the tumours was faster in group R0 than in group S0 on visual analysis, and the washout half-time estimated by region of interest analysis was shorter in group R0 than in group S0. Biodistribution studies revealed that 99mTc-MIBI accumulation in tumours (expressed as %ID/g) was also lower in group R0 than in group S0. MS-209 delayed the 99mTc-MIBI washout from KB-C1 tumours. Washout half-time was longer in groups R50, R100 and R200 than in group R0. A higher %ID/g was observed in groups R100 and R200 than in group R0. In KB-3-1 tumours, MS-209 had no effect on the washout half-time or the %ID/g. This study demonstrated that MS-209 increases the 99mTc-MIBI accumulation in Pgp-positive tumours. The MDR-reversing effect of MS-209 could be effectively evaluated with 99mTc-MIBI visually and non-invasively in vivo. 99mTc-MIBI imaging with MS-209 prior to chemotherapy should contribute significantly to the treatment strategy in patients with multidrug-resistant tumours.

While fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) is helpful in the pretherapeutic evaluation of head and neck cancer, it is only available in selected centres. Therefore, single-photon emission tomography (SPET) tracers would be desirable if they were to demonstrate tumour uptake reliably. This multitracer study was performed to evaluate the pretherapeutic uptake of the SPET tracers iodine-123 alpha-methyl-L-tyrosine (IMT) and technetium-99m hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) in primary carcinomas of the hypopharynx and larynx and to compare the results with those of FDG PET. We examined 22 fasted patients (20 male, 2 female, mean age 60.5+/-10.2 years) with histologically confirmed carcinoma of the hypopharynx (n=9) or larynx (n=13), within 1 week before therapy. In 20 patients a cervical PET scan was acquired after intravenous injection of 232+/-43 MBq 18F-FDG. Data analysis was semiquantitative, being based on standardised uptake values (SUVs) obtained at 60-90 min after injection. After injection of 570+/-44 MBq 99mTc-MIBI, cervical SPET scans (high-resolution collimator, 64x64 matrix, 64 steps, 40 s each) were obtained in 19 patients, 15 and 60 min after tracer injection. Finally, 15 min after injection of 327+/-93 MBq 123I-IMT (medium-energy collimator, 64x64 matrix, 64 steps, 40 s each) SPET scans were acquired in 15 patients. All images were analysed visually and by calculating the tumour to nuchal muscle ratio. Eighteen of 20 (90%) carcinomas showed an increased glucose metabolism, with a mean SUV of 8.7 and a mean carcinoma to muscle ratio of 7.3. The IMT uptake was increased in 13 of 15 (87%) patients, who had a mean carcinoma to muscle ratio of 2.9. Only 13 of 19 (68%) carcinomas revealed pathological MIBI uptake, with a mean tumour to muscle ratio of 2.2 and no significant difference between early and late MIBI SPET images (P=0.23). In conclusion, in the diagnosis of primary carcinomas of the hypopharynx and larynx, IMT SPET achieved a detection rate comparable to that of FDG PET. IMT SPET was clearly superior to MIBI SPET in this population. A further evaluation of the specificity of IMT in a larger number of patients appears justified.