Effect of intracoronary streptokinase administered immediately after primary percutaneous coronary intervention on long-term left ventricular infarct size, volumes, and function.

OBJECTIVES: The purpose of this study was to investigate the reflections of the improvement in microvascular perfusion provided by adjuvant intracoronary streptokinase (ICSK) on late-phase infarct size and left ventricular volumes and functions. BACKGROUND: It has been shown that ICSK given immediately after primary percutaneous coronary intervention (PCI) improves myocardial perfusion in the early days of ST-segment elevation acute myocardial infarction. METHODS: Ninety-five patients undergoing primary PCI were randomized to ICSK 250 kU (n = 51) or no additional therapy (n = 44). Two days later, coronary hemodynamic indexes were measured to evaluate tissue-level perfusion. After 6 months, angiography, echocardiography, and technetium-99m single-photon emission computed tomography (SPECT) were performed. RESULTS: At 2 days, all indexes of microvascular function were significantly better in the ICSK group than in the control group, including coronary flow reserve (2.5 vs. 1.7, p < 0.001) and index of microvascular resistance (20.2 vs. 34.2, p < 0.001). At 6 months, infarct size (22.7% vs. 32.9%; p = 0.003) and left ventricular end-systolic (41.1 ml vs. 60.9 ml; p = 0.009) and end-diastolic volumes (95.5 ml vs. 118.3 ml; p = 0.006) were significantly smaller, and the ejection fraction was significantly higher (57.2% vs. 51.8%; p = 0.018) in the ICSK group compared with the control group. CONCLUSIONS: In this study, it has been demonstrated that low-dose ICSK given immediately after primary PCI significantly limits long-term infarct size and preserves left ventricular volumes and functions. (Effect of Complementary Intracoronary Streptokinase Administration Immediately After Primary Percutaneous Coronary Intervention on Microvascular Perfusion and Late Term Infarct Size in Patients With Acute Myocardial Infarction; NCT00302419).

Determination of remnant thyroid volume: comparison of ultrasonography, radioactive iodine uptake and serum thyroid-stimulating hormone level.

PURPOSE: We aimed to evaluate the accuracy of ultrasonography, radioactive iodine uptake and serum thyroid-stimulating hormone level in predicting the volume of remnant thyroid gland. METHODS: Sixty-six thyroidectomy patients were divided into two groups according to their functional status, i.e. those operated upon for nontoxic multinodular goitre (group one) and those operated upon for hyperthyroidism (group two). Ultrasonography, radioactive iodine uptake and thyroid-stimulating hormone assay were performed in all patients during the first post-operative month. The two groups were subdivided according to the amount of remnant thyroid volume detected on ultrasonography: <2 ml, 2-5 ml and >5 ml. RESULTS: The remnant thyroid volume was positively correlated with the radioactive iodine uptake (rs = 0.684, p = 0.0001). The increase in remnant thyroid tissue radioactive iodine uptake was significantly greater in the patients operated upon for hyperthyroidism compared with those operated upon for nontoxic multinodular goitre (p = 0.0001). There was a negative correlation between remnant thyroid volume and post-operative serum thyroid-stimulating hormone level (rs = -0.865, p = 0.0001) and between remnant thyroid tissue radioactive iodine uptake and post-operative serum thyroid-stimulating hormone level (rs = -0.682, p = 0.0001). CONCLUSION: Ultrasonography is a more accurate measure of remnant thyroid volume than radioactive iodine uptake in patients operated upon for hyperthyroidism, compared with those operated upon for nontoxic multinodular goitre.

Gamma probe-guided surgery for revision thyroidectomy: in comparison with conventional technique.

Reoperative thyroid surgery may be required in patients who undergo any procedure less than total or near total thyroidectomy. The aim of this study was to investigate advantages of gamma-probe guided revision thyroidectomy (GGRT) over conventional revision thyroidectomy (CRT) in patients with differentiated thyroid carcinoma (DTC). GGRT was assessed according to the TSH values, complication rates and the incidence of carcinoma in residual thyroid tissue. In this randomised prospective clinical trial, 25 patients with differentiated thyroid carcinoma who had previously undergone surgery for benign multinodular goiter were included in the study. GGRT was performed in 11 (44%) patients (Group 1) and CRT in 14 (65%) (Group 2). The intraoperative mean ratio of thyroid activity to background activity (T/B) was detected as 5.1 +/- 1.4 and the mean ratio of thyroid bed activity to background activity after excision (Tbed/B) was 1.3 +/- 0.3, (p < 0.01). Although the incidence of carcinoma in residual thyroid tissue was higher in group 1 (4/11) in comparison to group 2 (1/14), it was not statistically significant. The elevation of the TSH concentration at the first post-operative month was significantly higher in group 1 in comparison with group 2 (18 +/- 25 5 +/- 3 mlU/l), (p < 0.02). These results indicate that intraoperative gamma probe application may be beneficial to detect and remove residual thyroid tissue in revision thyroidectomy.

99Tc-HmPAO SPECT in 13 patients with classic lissencephaly.

In this study, technetium-99 ((99)Tc)-hexamethylpropyleneamine-oxine single-photon emission computed tomography (SPECT) was performed on 13 children with classic lissencephaly (nine with epileptic seizures, four without seizures). Focal or multifocal hypoperfusions were observed in 12 patients. The hypoperfused areas observed on SPECT scanning did not correlate with the localization of agyric-pachygyric regions in all patients. The distribution of perfusion abnormalities by SPECT and the localization of agyria-pachygyria as detected by magnetic resonance imaging did not correlate strongly. All nine patients with seizures and three of the four patients without seizures had focal or multifocal cerebral blood flow abnormalities on the SPECT scans. The presence of brain perfusion abnormalities detected by SPECT and the occurrence of epileptic seizures did not have a significant relationship. These results suggest that the role of SPECT studies in classic lissencephaly is not clearly defined. More sophisticated methods are needed to clarify the correlation between structural and functional abnormalities of patients diagnosed with lissencephaly.

Disappointing results with Tc-99m tetrofosmin for detecting medullary thyroid carcinoma metastases comparison with Tc-99m VDMSA and TI-201.

PURPOSE: This prospective study assessed the detectability of metastatic lesions by Tc-99m tetrofosmin in medullary thyroid carcinoma and to compare the results with Tc-99m penta dimercapto succinic acid (VDMSA) and TI-201. METHODS: A prospective study was performed on 24 patients (10 men, 14 women; ages 23 to 76 years) with medullary thyroid carcinoma after total thyroidectomy. Five cases were sporadic and 19 were familial. After the injection of 740 MBq (20 mCi) tetrofosmin, 740 MBq (20 mCi) VDMSA and 74 MBq (20 mCi) TI-201, whole-body scans and 5-minute static images of the head, neck, chest, abdomen and pelvis were obtained. All scintigraphic studies were compared with calcitonin levels, radiologic findings, histopathologic results, and clinical follow-up. RESULTS: Thirty-four metastatic sites were detected in 12 patients on the basis clinical, radiologic, and histopathologic findings. Patients were divided into three groups according to the calcitonin levels and scintigraphic findings. Group 1 consisted of patients with elevated calcitonin levels and positive scintigraphic findings. Among 34 metastatic sites, 30 could be detected with VDMSA. Only 21 and 20 metastatic sites could be visualized with TI-201 and tetrofosmin, respectively. All 30 lesions showed intense VDMSA uptake but only faint or no uptake with TI-201 and tetrofosmin. Patients in group 2 were accepted to have micrometastases. In this group, calcitonin was minimally elevated, and the results of all three scintigraphs were negative. Group 3 included patients with true-negative results. All patients had normal calcitonin levels and negative results of scintigraphic studies. CONCLUSIONS: Tetrofosmin has no role in the detection of medullary thyroid carcinoma metastases. These results show that VDMSA is clearly superior to TI-201 and tetrofosmin in the follow-up of patients with medullary thyroid carcinoma.

Determination of medullary thyroid carcinoma metastases by 201Tl, 99Tcm(V)DMSA, 99Tcm-MIBI and 99Tcm-tetrofosmin.

Medullary carcinoma of the thyroid (MCT) is malignancy derived from the parafollicular cells (or C-cells) of the thyroid. It is usually sporadic, although it is familial in some cases. Several scintigraphic procedures can provide information regarding the primary and metastatic foci of the tumour. We performed whole-body scanning to establish the pathology of MCT using 201Tl, 99Tcm(V)DMSA and 99Tcm-MIBI in 14 patients, and found average sensitivities of 73%, 82% and 81%, respectively. Moreover, we also scanned three patients with 99Tcm-tetrofosmin and identified two of four pathological foci as well as residual thyroid tissue. The sensitivities of 201Tl, 99Tcm(V)DMSA and 99Tcm-MIBI were 100%, 100% and 85% in identifying lymphadenopathies; 40%, 50% and 71% for soft tissue foci; 100% and 100% for foci in pulmonary parenchyma; and 100%, 66% and 100% for recurrences in thyroid gland. Although 99Tcm(V)DMSA identified all bony metastases in three patients (100%), 99Tcm-MIBI detected only two of three foci (66%) and 201Tl none. 201Tl, 99Tcm-MIBI and 99Tcm-tetrofosmin accumulated in residual thyroid tissue, but 99Tcm(V)DMSA did not, as expected. We conclude that these agents were complementary, since they had different sensitivities in different tissues. The tumour-seeking properties of tetrofosmin are to be evaluated in a larger series.

Thallium-201, technetium-99m-tetrofosmin and iodine-131 in detecting differentiated thyroid carcinoma metastases.

UNLABELLED: The purpose of this study was to asses the detectability of differentiated thyroid carcinoma (DTC) metastases by 99mTc-tetrofosmin and to compare the results of 99mTc-tetrofosmin with 131I and 201Tl. The reliability of 201Tl and 99mTc-tetrofosmin scanning during suppression therapy also has been studied. METHODS: A prospective study was performed on 41 patients (30 females, 11 males) with DTC (30 papillary, 11 follicular) who had undergone total thyroidectomy and received an average dose of 117 mCi (4329 MBq) of radioiodine for ablation of postsurgical residual thyroid tissue. All patients (n = 41) had 201Tl, 99mTc-tetrofosmin or 131I whole-body imaging after discontinuation of thyroid hormone replacement (thyroxine-off group). Eight of 14 patients with distant metastases also were imaged when they were on thyroxine therapy both with 201Tl and 99mTc-tetrofosmin (thyroxine on-and-off group). Radiologic studies (chest radiography, CT and MRI), serum thyroglobulin assays and histopathologic examinations were performed to clarify the presence of metastases with positive uptake on any of three radionuclide studies. RESULTS: In 26 of 41 patients all three scans were negative. These patients also clinically didn't show any evidence of metastases. Fourteen patients were considered to have distant metastases on the basis of clinical, radiologic and histopathologic findings. The sensitivities of 201Tl, 99mTc-tetrofosmin and 131I in diagnosing distant metastases were comparable (0.85, 0.85 and 0.78, respectively). Iodine-131 was much more sensitive than 201Tl and 99mTc-tetrofosmin for demonstrating residual thyroid tissue after surgery (1.00, 0.33 and 0.33, respectively). The only false-positive case involved radioiodine uptake in a tuberculoma. Thyroxine-on images of 8 patients with distant metastases showed no difference from their thyroxine-off images regarding the site, number and uptake of metastases. CONCLUSION: Technetium-99m-tetrofosmin and 201Tl imaging are highly sensitive for detecting differentiated thyroid carcinoma metastases and do not require prior withdrawal of thyroid hormone suppressive therapy.

99Tc(m)-polyclonal IgG scintigraphy in the detection of infected hip and knee prostheses.

We investigated the usefulness of 99Tc(m)-polyclonal human IgG (99Tc[m]-HIG) scintigraphy in the diagnosis of infected hip and knee prostheses. Twenty-nine scintigraphic studies were performed in 27 patients (17 females, 10 males) with a suspected prosthetic infection. As some patients had bilateral prostheses, a total of 35 prostheses were evaluated. There were 25 hip replacements and 10 knee prostheses. The images were analysed both visually and quantitatively. The scintigraphic results were compared with the culture results of surgical specimens and also with clinical follow-up after 3 months. Increased uptake was observed in 22 prostheses, of which 12 were true-positive and 10 were false-positive results. Staphylococci were the agents most commonly isolated. In all false-positive patients, aseptic inflammation was diagnosed. Based on quantitative analysis, no statistically significant difference was found between the true-positive and false-positive cases. For the prostheses as a whole, the sensitivity, specificity, positive predictive value and negative predictive value were 100%, 41%, 54% and 100% respectively. For the hip prostheses alone, these values were 100%, 53%, 57% and 100% respectively. Taking its high sensitivity and predictive value into consideration, 99Tc(m)-HIG scintigraphy can be used as a screening test to help eliminate prosthetic infection.

99Tcm-tetrofosmin scintigraphy in the evaluation of palpable breast masses.

201Tl and 99Tcm-MIBI have been used to evaluate palpable breast masses. The aim of this study was to evaluate the potential of 99Tcm-tetrofosmin as a new tumour localizing agent in patients with palpable breast masses. Nineteen palpable breast masses were evaluated in 18 patients. Each patient received 740 MBq 99Tcm-tetrofosmin intravenously. Ten minutes after the injection, planar breast images in the anterior, right lateral and left lateral views were obtained with the patient in the supine position. Mammography and ultrasonography were performed in all patients. Biopsy or mastectomy with axillary dissection was performed in all patients. Thirteen of 14 primary breast tumours were detected (9 invasive ductal carcinomas, 3 invasive lobular carcinomas, 1 papillary carcinoma). One patient with mucinous carcinoma did not demonstrate 99Tcm-tetrofosmin accumulation. Four of five patients with histopathologically proven benign lesions did not demonstrate 99Tcm-tetrofosmin accumulation (2 fibrocystic diseases, 2 fibroadenomas). 99Tcm-tetrofosmin accumulation was seen in a patient with chronic mastitis. The sensitivity and specificity of 99Tcm-tetrofosmin for malignant breast lesions was 92 and 80% respectively. Four of seven (57%) axillary lymph node metastases showed 99Tcm-tetrofosmin uptake. In conclusion, 99Tcm-tetrofosmin shows real promise for use in evaluating patients with palpable breast masses.

Comparison of Tc-99m MIBI and Tl-201 uptake in musculoskeletal lesions.

The aim of this study was to make a comparison between the uptake of Tc-99m MIBI and Tl-201 in evaluation of musculoskeletal lesions. Fourteen cases were studied. Each study consisted of a Tl-201 study followed by a Tc-99m MIBI scan. In addition, a whole-body bone scan was performed in each patient to visualize bone metastases. Tl-201 and Tc-99m MIBI uptakes were evaluated by visual assessment and by using lesion-to-background (L/B) ratio. The authors found increased Tl-201 uptake with a mean L/B ratio of 2.81 and less Tc-99m MIBI uptake with a mean L/B ratio of 2.18 in malignant lesions. Both agents showed lower uptake with mean L/B ratios of 1.6 and 1.2 in benign lesions, but there was no statistical difference between the uptakes of either Tl-201 or Tc-99m MIBI in those with malignant and those with benign lesions. In addition, false-positive imaging was observed with both Tl-201 and Tc-99m MIBI. The results demonstrated that Tl-201 and Tc-99m MIBI accumulations in musculoskeletal lesions are not specific for malignancy.

Visualization of a perforated small bowel duplication during Meckel's scintigraphy.

A case of a small bowel tubular duplication is described. It was lined with ectopic gastric mucosa which showed a perforation. The diagnosis was made preoperatively by Tc-99m pertechnetate scintigraphy.

Thallium-technetium-subtraction scintigraphy in secondary hyperparathyroidism.

Between 1983 and 1992 thallium-technetium subtraction scintigraphy (TTS) was performed on 74 patients with clinical and biochemical evidence of hyperparathyroidism. Twenty-five of the 53 investigations since 1988 were conducted on patients with renal failure with a suspicion of secondary hyperparathyroidism. In a retrospective study we have evaluated radioisotope scintigraphy for patients with adenoma and for renal failure patients with possible parathyroid hyperplasia. Thirty of 74 patients underwent neck exploration. Scintigraphy detected 17 of 24 parathyroid adenomas (sensitivity 71%). In contrast, in six renal patients who came to operation, scintigraphy localised only 5 of 20 hyperplastic parathyroid glands (sensitivity 25%) and in one renal patient we localised a parathyroid adenoma. A review of the literature shows low detection rates for hyperplasia by TTS to be a common observation. Based on these findings a rational approach is offered for parathyroid localisation in renal patients prior to neck exploration.

Poor-quality red blood cell labelling with technetium-99m: case report and review of the literature.

Technetium-99m red blood cell (RBC) venography is a simple and sensitive technique for the diagnosis of deep vein thrombosis of the lower limb, but optimal labelling of the blood pool is essential for a diagnostic study. Here we report the case of a 44-year-old male with deep vein thrombosis of the right leg. RBC venography of the lower extremities showed poor labelling. In addition we review the literature on the subject.