Success of minimally invasive single-gland exploration using the quick intraoperative parathyroid assay.

OBJECTIVE: Using accurate localization techniques and the quick intra-operative parathyroid assay (QPTH), surgery for primary hyperparathyroidism due to a solitary adenoma has moved from the traditional wide bilateral neck exploration to more limited approaches such as minimally invasive single-gland exploration (MISGE) and minimally invasive radio-guided parathyroidectomy (MIRP). This study investigated whether the MISGE could take the place of MIRP with the help of the QPTH. DESIGN: From 2007 to 2009, 56 patients with primary hyperparathyroidism were studied. All patients were pre-operatively investigated by imaging techniques to improve the pre-operative determination of adenomas. Twenty-five patients were in the MIRP group and 31 in the MISGE group. QPTH was routinely measured; a 50% reduction in the QPTH level indicated complete excision. RESULTS: There were no differences in the complication rates, surgical time, anaesthesia time or mean length of hospital stay between the groups. However, total hospital charges were more favourable in the MISGE group with a mean saving of $400 per case. CONCLUSION: This study demonstrates that with the additon of the QPTH, MISGE can be performed as a quick and reliable procedure in correct adenoma removal instead of MIRP. Moreover MISGE achieves the optimal time interval between injection and exploration, reduces the radiation exposure of both patient and surgeon, decreases the cost, and decreases usage of pre-operative imaging and intra-operative equipment.

Hypoglycemia induced by long-acting somatostatin analogues in a patient with nonfunctional neuroendocrine tumor.

Somatostatin and its long-acting analogues are effective in symptom control in patients with functional neuroendocrine tumors; they are also able to control tumor growth. Somatostatin analogues are safe and generally well tolerated. In some cases they may cause serious complications. Somatostatin analogues are potent inhibitors of growth hormone (GH) and glucagon secretion. They cause impairment of hepatic glucose output and delay in intestinal absorption of carbohydrates. Patients with huge tumor mass and multiple liver metastases have increased risk of tumor-induced hypoglycemia. In these patients, long-acting octreotide may trigger serious hypoglycemia. The patients whose glucose control is dependent on counter-regulatory hormones should be monitored for the possibility of hypoglycemia. Herein, we present a patient with severe and prolonged hypoglycemia after long-acting octreotide treatment.

Technetium-99m hexamethylpropylene amine oxime lung scintigraphy findings in low-dose amiodarone therapy.

Amiodarone (AD)-induced pulmonary toxicity is one of the major complications of long-term AD therapy. Technetium-99m-labeled D: ,L: -hexamethylpropylene amine oxime (Tc-99m HMPAO) scintigraphy has been used to assess lung injury. We designed this study to clarify lung uptake changes of Tc-99m HMPAO using low doses of AD (5 mg/kg/day) during long-term therapy in a rabbit model. Group 1 consisted of 7 rabbits fed with AD by gavage for 6 months. To investigate the effect of ketamine on Tc-99m HMPAO uptake, 5 rabbits were included in Group 2 as a control group. Tc-99m HMPAO scintigraphy was performed in both Group 1 and Group 2 at baseline and after 2, 4, 6, 8, and 12 weeks of AD intake. After 16, 20, and 24 weeks of drug intake, Tc-99m HMPAO scintigraphy was repeated only in group 1. One-min anterior images were acquired 30 min after the injection of 37 MBq of Tc-99m HMPAO. For semiquantitative evaluation, the mean count values were obtained and lung/background and liver/background ratios were calculated. Histopathologic evaluation was performed. No increase in lung and liver uptake of Tc-99m HMPAO was found 2, 4, 6, 8, and 12 weeks after drug intake. There was no significant increase in L/B and H/B ratios of Tc-99m HMPAO in Group 1 compared with Group 2. Both scintigraphic studies and histopathologic examinations showed nonspecific changes. Longitudinal studies investigating Tc-99m HMPAO lung uptake may be planned in patients carrying risk factors for AD-induced lung toxicity.

The role of gamma probe activity counts in minimally invasive parathyroidectomy. Preliminary results.

AIM: The benefit of preoperative gamma probe in the diagnosis of adenoma in patients with histopathologically proven parathyroid (PT) adenomas was examined. PATIENTS, MATERIAL, METHODS: 20 patients with positive (99m)Tc MIBI uptake in PT scintigraphy with primary hyperparathyroidism were enrolled in this study. 740 MBq (99m)Tc MIBI were injected 3 h before operation. Counts of four PT regions were obtained with gamma probe before surgery in the operation room. All suspected PT adenomas were resected and histopathologically diagnosed as adenomas. We also obtained counts of the resection region and the resected adenoma with gamma probe after the parathyroidectomy. Preoperative counts of adenoma bearing regions (ABR), non-adenoma bearing regions (NABR), postoperative resection region (PRR), resected adenoma counts (RA) were registered. Statistical analysis was performed by Wilcoxon rank test. RESULTS: The mean counts of ABR, NABR, the PRR and RA were 462 +/- 106, 230 +/- 66, 164 +/- 42, 374 +/- 87, respectively. The mean counts from ABR were twofold higher than those of NABR. The PRR mean counts decreased by 64% when compared to the mean counts of ABR and by 55% when compared to the mean counts of RA. The differences in mean counts of ABR and NABR, PRR and ABR, PRR and RA (p <0.01) turned out as statistically significant. DISCUSSION: According to our preliminary results, the region with the highest counts is at least 2 +/- 0,4 times higher than the mean of the other three PT regions. Thus, it seems to be significant for PT adenoma. Resection of adenoma may be accepted as successful, if the count of ABR decreased more than 64% with decreased postoperative parathormone levels. CONCLUSION: This technique should not yet be applied instead of parathormone measurement or frozen technique. But it may replace the frozen technique used for confirmation of the diagnosis during the operation in the future.

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

AIM: 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. PATIENTS AND METHOD: 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. 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. CONCLUSION: 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.

New radiolabeled CCK-8 analogues [Tc-99m-GH-CCK-8 and Tc-99m-DTPA-CCK-8]: preparation and biodistribution studies in rats and rabbits.

The aim of this study is to label CCK-8 with Tc-99m and to investigate its radiopharmaceutical potential. CCK-8 was labeled with Tc-99m using GH and DTPA as bifunctional chelating agents. Labeling efficiency was higher than 99%. Complex was stable more than 5 hours at room temperature. 37 MBq Tc-99m-GH-CCK-8 or Tc-99m-DTPA-CCK-8 was administered intravenously to rabbits for biodistribution experiments. Dynamic and static images were obtained from anterior projection using a Camstar XC/T gamma camera. For quantitative evaluation, regions of interest were drawn on organs and time-activity curves were generated. The highest accumulation occurred in brain within 10 and 30 minutes after injection. Renal and hepatobiliary excretion were observed. Brain distribution studies in rats showed the highest activity was in hypothalamus. Results demonstrated that Tc-99m-GH-CCK-8 and Tc-99m-DTPA-CCK-8 analogs may be a useful new class of receptor-binding peptides for diagnosis and therapy of brain diseases related with CCK-B receptor-expressing tumors.

Use of technetium-99m HMPAO scintigraphy for the detection of amiodarone lung toxicity in a rabbit model.

Amiodarone (AD) is a very effective anti-arrhythmic drug, but its use is often associated with serious pulmonary complications such as pneumonitis and interstitial pulmonary disease. The aim of this study was to investigate the relationship between the amount of amiodarone intake (and the related development of lung toxicity) and the lung uptake of technetium-99m labelled D,L-hexamethylpropylene amine oxime (HMPAO). Eighteen white female New Zealand rabbits were divided into three groups and fed AD by gavage at doses of 10 (group A), 50 (group B) or 150 (group C) mg/kg daily. 99mTc-HMPAO scintigraphy was performed at baseline and after 1, 2, 3 and 4 weeks of drug intake. Anterior images of 1 min duration were acquired at 30 min after the injection of 37 MBq 99mTc-HMPAO. Regions of interest (ROIs) were drawn on the lungs (L) and the upper limb (B) as the background. L/B ratios were calculated using the mean counts. In groups A and B histopathological evaluation of the lungs of all rabbits was performed at the end of the 4 weeks of AD intake, while in group C it was performed at 2 weeks because of increased mortality. At baseline, mean L/B ratios for groups A, B and C were 2.8 +/- 0.3, 2.8 +/- 0.3 and 2.8 +/- 0.4, respectively. After 3 weeks of AD intake, L/B ratios increased to 4.1 +/- 0.6 and 4.8 +/- 0.6 in groups A and B, respectively. The L/B ratio was 3.6 +/- 0.2 after 1 week of AD intake in group C. The correlation coefficients between the lung uptake of 99mTc-HMPAO and AD doses for groups A, B and C were r = 0.51 (P = 0.037), r = 0.74 (P = 0.0002) and r = 0.96 (P = 0.0001), respectively. Histopathological findings related to AD lung toxicity, such as interstitial pneumonitis and foamy alveolar macrophages, were observed more frequently in groups B and C than in group A. According to our findings, 99mTc-HMPAO lung uptake is correlated with AD dose. 99mTc-HMPAO lung imaging can demonstrate AD-induced lung injury.

Tc-99m MDP, thallium-201 chloride and Tc-99m MAG3 renal uptake in subacute and chronic radiation nephritis compared.

The authors present a comparison of the findings for thallium-201 (Tl-201), Tc-99m MAG3 and Tc-99m MDP in subacute and chronic radiation nephritis in a 9-yr-old boy who was treated by radiation therapy for alveolar rhabdomyosarcoma of the left chest wall by a radiation port that partially included the left kidney. Tl-201 imaging three and six months later showed a cortical defect in the left kidney due to radiation nephritis. Tc-99m MDP scan showed increased uptake on both occasions, but more marked in the subacute period than in the chronic period. Tc-99m MAG3 showed decreased concentration and increased cortical retention three months later. Six months after the radiation therapy, a cortical defect corresponding to the cortical area that showed increased parenchymal retention was more prominent in the Tc-99m MAG3 scan. In the present case, Tc-99m MDP, Tl-201 and Tc-99m MAG3 findings may provide useful information for understanding pathophysiological damage in the kidney after radiation.

Indium-111 octreotide uptake in the surgical scar.

Indium-111 octreotide uptake has been reported in various somatostatin receptor positive tumors, granulomas and autoimmune diseases in which activated leucocytes may play a role, subcutaneous cavernous hemangioma and angiofibroma. We present Indium-111 octreotide uptake in a surgical abdominal scar tissue 1.5 and 6 months after surgery in a patient who had been treated for recurrent carcinoid tumor in the rectosigmoid junction. Indium-111 octreotide uptake in a surgical scar may be related to the binding to somatostatin receptors in the activated lymphocytes and fibroblasts that is previously reported.