Tc-99m MIBI (MIBI) is a cationic lipophilic agent, which has traditionally been used for myocardial perfusion scintigraphy, detection and monitoring of different benign and malignant tumors. The objective of this study was to evaluate the frequency of pituitary incidentalomas detected on MIBI scans performed on patients with suspected parathyroid adenomas and to provide semiquantitative analysis of tracer uptake in the pituitary region. Tomographic images of MIBI scans on 56 patients with suspected parathyroid adenomas (2006-2007) were analyzed retrospectively. Semiquantitative analysis of abnormal uptake was performed by drawing identical regions of interest (ROI) over the pituitary area and the normal brain on one transverse section that demonstrates the lesion most clearly. Pituitary uptake to normal brain uptake ratio was calculated in all cases. We found statistically significant differences of MIBI uptake in patients with pituitary adenomas, mean ratio: 29.78±12.17 (median 29.77, and range 19-41), compared with patients with no pathologic changes in this region, mean ratio was 5.88±1.82 (median was 5.95 and range 2.0- 9.2). As the groups are too small for statistical analysis, these results need to be confirmed in a larger cohort and should include more detailed biochemical correlation. MIBI parathyroid scintigraphy should be taken into account as a potential source of identifying pituitary incidentalomas. Clinical significance of these findings needs further evaluation.

Ablative approaches using radioiodine are increasingly proposed for the treatment of Graves' disease (GD) but their ophthalmologic and biological autoimmune responses remain controversial and data concerning clinical and biochemical outcomes are limited. The aim of this study was to evaluate thyroid function, TSH-receptor antibodies (TRAb) and Graves' ophthalmopathy (GO) occurrence after radioiodine thyroid ablation in GD. We reviewed 162 patients treated for GD by iodine-131 (¹³¹ I) with doses ranging from 370 to 740 MBq, adjusted to thyroid uptake and sex, over a 6-year period in a tertiary referral center. Collected data were compared for outcomes, including effectiveness of radioiodine therapy (RIT) as primary endpoint, evolution of TRAb, and occurrence of GO as secondary endpoints. The success rate was 88.3% within the first 6 months after the treatment. The RIT failure was increased in the presence of goiter (adjusted odds ratio = 4.1, 95% confidence interval 1.4-12.0, P = 0.010). The TRAb values regressed with time (r = −0.147; P = 0.042) and patients with a favorable outcome had a lower TRAb value (6.5 ± 16.4 U/L) than those with treatment failure (23.7 ± 24.2 U/L, P < 0.001). At the final status, 48.1% of patients achieved normalization of serum TRAb. GO occurred for the first time in 5 patients (3.7%) who were successfully cured for hyperthyroidism but developed early and prolonged period of hypothyroidism in the context of antithyroid drugs (ATD) intolerance (P = 0.003) and high TRAb level (P = 0.012). On the basis the results of this study we conclude that ablative RIT is effective in eradicating Graves' hyperthyroidism but may be accompanied by GO occurrence, particularly in patients with early hypothyroidism and high pretreatment TRAb and/or ATD intolerance. In these patients, we recommend an early introduction of LT4 to reduce the duration and the degree of the radioiodine-induced hypothyroidism.

After undergoing radionuclide therapy, patients generate wastewater with a considerable amount of radioactivity, which can reach levels of as much as 90% of the administered dose. Due to the risk of accumulation after discharge into the sewer, it is advisable to collect this effluent for its treatment prior to final discharge. Delay and decay (natural decomposition of the isotope) is the most commonly used technical method of abating radioactive iodine, but it is frequently criticized as being complex and very expensive. BioChroma is a technology that has been developed as an alternative to these complicated and expensive systems. This paper describes this new technology and presents, as an example, a system that was installed and successfully commissioned in the middle of 2008 in a nuclear medicine ward with 12 beds in Stuttgart (Germany). Based on existing legislation, the responsible authorities and the company that operated the hospital agreed on a maximum activity level of 5 Bq/l. If a typical delay and decay system would have been installed, the 180 m³ treatment plant that was already available in the hospital cellar would have to be extended by additional 150 m³. By implementing the patented BioChroma process, the space requirements were reduced by 75%. For instance, since the new system was integrated into the existing installation, tanks accounting for 120 m³ could be used as buffering volume in the new wastewater treatment plant. The operation of the referred plant is currently producing very good results with values below the specified limit of 5 Bq/l for the isotope ¹³¹ I. In addition, ⁹⁰ Y has been reported to be eliminated at the same time. Over the past 2 years of operation, the wastewater treatment plant has been able to achieve a maximum processing capacity of more than 2,000 l/day, which equates to a nuclear medicine ward with approx. 20 beds. The highest level recorded during the test period (of 180 days after start-up) was a peak of nearly 2,800 l/day.

Two patients demonstrated an unusual pattern of intense bone and surrounding soft tissue hypermetabolic uptake in the posterior pelvis on fluorodeoxyglucose positron emission tomography with computed tomography PET-CT scans. After further investigation, we found that both patients underwent uncomplicated autologous bone marrow harvesting several weeks before imaging. These two cases illustrate a distinctive PET-CT appearance following bone marrow harvesting that the radiologist needs to recognize to not confuse the findings with metastatic disease.

¹⁸ F-Fluoro-deoxyglucose-positron emission tomography/computed tomography findings in a case presenting with pyomyositis are presented in this report.

Cutaneous metastases from internal malignancies are rare with a reported incidence between 0.7% and 10%. We report a case with distant skin and subcutaneous metastases in abdominal skin from breast cancer detected on ¹⁸ F-fluoro-deoxyglucose-positron emission tomography/computed tomography imaging.

We report the findings of [18F] fluoro-deoxy-glucose (FDG) positron emission tomography (PET) performed in a 67-year-old female with suspicion of gastric carcinoma. Intense FDG uptake was noted in the thickened gastric wall. Subsequent laparotomy showed diffuse involvement of the gastric wall by signet ring cell adenocarcinoma. This report highlights FDG PET/CT pattern in linitis plastica of the stomach caused by primary signet cell adenocarcinoma.

Dual left anterior descending artery (LAD) is a rare variation in the coronary artery anatomy having 4 different subtypes. We report a rare scenario of type IV dual LAD, with short LAD critical stenosis, compensated by a long LAD perfusing the same territory, which was missed on initial angiographic evaluation. Myocardial perfusion scan (MPS) of this patient showed preserved perfusion. A review of angiogram revealed this anomaly, indicating that a meticulous correlation of anatomic and functional modalities is necessary as it could change further management of patient.

Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults, and is generally of poor prognosis. The post-treatment assessment of GBMs is a known diagnostic issue, with problems in the differentiation of viable remnant tumor and post-treatment inflammatory changes. We present a case where various molecular tracers (fluorodeoxyglucose, choline, and methoxyisobutylisonitrile) were used in the post-treatment assessment of a patient with histologically proven GBM.

Cardiac metastasis occurs in up to a quarter of patients with metastatic cancer and is seen most commonly in melanoma and lymphoma. Metastatic involvement of the heart and pericardium may go unrecognized until autopsy. We describe a patient of non-Hodgkin's lymphoma detected to have involvement of right atrium on F-18 FDG PET/CT and monitoring of response to chemotherapy.

The Tako-Tsubo syndrome is a reversible form of an acute stress-related cardiomyopathy that was reported during the last decade. It typically presents with a constellation of symptoms, electrocardiographic changes, and elevated cardiac enzyme levels consistent with an acute coronary syndrome. However, when the patient undergoes cardiac angiography, left ventricular apical ballooning finding is seen, but no significant coronary artery stenosis. This balloon-like morphology, being the hallmark of this entity, can be detected by imaging. We present a case report of a patient who was admitted to our hospital and met all the diagnostic criteria of the Tako-Tsubo syndrome. Myocardial perfusion imaging (MPI) showed an anteroapical perfusion defect at rest, moderated systolic dysfunction, and intraventricular asynchrony all assessed by gated-SPECT phase analysis. Two months later, all MPI findings returned to normal parameters.

In this report, we describe a rare case of brown tumor and mediastinal parathyroid adenoma. This report emphasizes the value of radionuclide scintigraphy in the setting of persistent disease following parathyroid surgery.

Renal metastases from thyroid carcinoma are very rare, late recurrences of papillary thyroid carcinomas (PTC) are not reported in literature and there is no universal recommendation for optimum duration of follow-up of thyroid carcinoma. We present herein a case of late renal recurrence of follicular variant PTC (FV-PTC). This study is a case report of renal metastasis revealing a late recurrence of FV-PTC. An 81-year-old woman with previously treated FV-PTC 24 years ago by total thyroidectomy, lymph nodes dissection and radioiodine therapy presented with sudden gross-hematuria. Computerized tomography scan (CT-scan) revealed a 70-mm right renal mass and histological diagnosis after nephrectomy demonstrated recurrence of FV-PTC with a positive thyroglobulin immunostaining. Despite of ¹³¹ I-radioiodine therapy postoperatively, the serum thyroglobulin (Tg) increased and positron emission tomography combined to CT-scan showed 4 years later, an abdominal lymph node and distant metastases. Now the patient is alive but her general condition is too poor for systemic adjuvant therapy. This case illustrates the need of prolonged follow-up after surgery of high-risk FV-PTC.