No abstract

99mTc (V) DMSA scintigraphy provides a noninvasive, practical, and accurate assessment of IBD activity.

In the present study we evaluated comparatively the diagnostic value of mammography, of 99mTc-sestamibi scintimammography (sestamibi-SC) and of colour Doppler ultrasonography (CD-US) in 116 breast lesions. Diagnosis was based on histopathological examination. Overall, out of 86 malignant tumours, 80 (93%) and 75 (87%) had a positive sestamibi-SC and positive CD-US, respectively. Out of 30 benign lesions, 25 (83%) and 26 (87%) had a negative sestamibi-SC and negative CD-US respectively. The true positive results were similar in palpable and in non-palpable lesions for both methods. Out of 19 non-palpable malignant tumours, mammography confirmed malignancy in only one case (5%), which was significantly lower than the results obtained by sestamibi-SC (89%; Px0.0001) and by CD-US (74%; P=0.0001). In palpable malignant tumours, by using mamography, true positive results were obtained in 54/67 (80.5%) patients, which was significantly lower than the results obtained by sestamibi-SC (94%; P=0.03) and marginally different to the results obtained by CD-US (91%; P=0.13). It is concluded that sestamibi-SC and CD-US are useful tools in clarifying the nature of breast lesions in cases with doubtful mammography. The clinical value of these diagnostic procedures in guiding subsequent therapeutic interventions requires further investigation.

Objective: To investigate ventricular sympathetic innervation in patients with sick sinus syndrome and to detect regional deterioration of adrenergic innervation caused by asynchronous ventricular activation from right ventricular pacing. Design: Prospective controlled study. Setting: Tertiary cardiac referral centre. Patients: 22 patients with sick sinus syndrome and indications for permanent dual chamber pacing; 20 healthy individuals as controls. Interventions: All patients underwent myocardial imaging with planar and single photon emission computed tomography (SPECT) after an intravenous infusion of 5 mCi 123 I-meta-iodobenzylguanidine ( 123 I-MIBG) before and after pacemaker implantation. A SPECT thallium 201 myocardial study was done during the same week as the 123 I-MIBG study in all patients. Main outcome measures: The heart to mediastinum (H/M) ratio and washout rate were calculated during the 123 I-MIBG study to assess the global cardiac sympathetic activity; the aim of the SPECT study was to investigate the regional distribution of adrenergic innervation. Results: The H/M ratio was significantly smaller in the patients with sick sinus syndrome than in the controls (p < 0.001). In sick sinus syndrome there were regional adrenergic innervation defects, mostly in the inferior and apical walls. After a medium term pacing period, a redistribution of 123 I-MIBG uptake was detected, with deterioration of adrenergic innervation in the inferior, apical, and posterior walls. The thallium 201 myocardial perfusion study showed no change after three months of permanent pacing. Conclusions: Patients with sick sinus syndrome have global and regional disturbances of the adrenergic innervation of the left ventricular myocardium. These seem to deteriorate as a result of asynchronous electrical activation. The clinical significance of this finding requires further investigation. S ick sinus syndrome, in which there is progressive dysfunction of the sinus node, is one of the most common indications for a permanent pacemaker. The sites that are normally used for electrode implantation in permanent cardiac pacing are the high right atrium and the apex of the right ventricle. However, it has been shown that pacing through the right ventricular apex is associated with alterations in the contraction and relaxation pattern of the left ventricle, 1-3 remodelling, and histological abnormalities in the left ventricular myocardium. [4][5][6][7] Recently, there have been indications that long term permanent pacing is related to abnormalities of regional perfusion and adrenergic innervation. However, there is a lack of comparable data on these perfusion and innervation disturbances before and after pacemaker implantation, so the net real effect of pacing has not been clarified. Patients with sick sinus syndrome have rhythm disturbances that may be associated with alterations in cardiac autonomic tone affecting myocardial adrenergic innervation, so it is important to know whether any adrenergic innervation defects found in paced pati...

Mammography is the screening test of choice for breast cancer. Its low specificity leads to a large number of unnecessary biopsies. Scintimammography, with either Tc-sestamibi (MIBI) or Tc-anti-carcinoembryonic antigen (CEA) Fab', has been proposed as a non-invasive test to lower the high false positive rate of mammography in certain patients. The two agents have not been compared, nor has their combined application been evaluated. We performed a prospective, non-randomized, open-label, single-centre study of 32 women with clinically and mammographically suspected breast cancer [Breast Imaging Reporting and Data System (BI-RADS, American College of Radiology) 4 or 5]. All patients underwent Tc-MIBI and Tc-anti-CEA Fab' scintimammography, and the results were correlated with histopathology. Overall, the accuracies for MIBI and CEA scans were 90.3% (28/31) and 77.4% (24/31), respectively. The probability of disease after mammography was 0.939+/-0.081 (95% confidence interval, CI). The post-mammography probabilities after positive MIBI or CEA scan were 0.965 and 0.960, respectively, and after negative MIBI or CEA scan 0.750 and 0.875, respectively. None of the above differences is significant. The post-test probability when both scans were positive (irrespective of which was performed first) was 0.977. It can be concluded that there are indications that scintimammography with Tc-MIBI is superior to that with Tc-anti-CEA Fab' when these tests are used as screening tests for breast cancer. However, mammography remains the screening test of choice for highly suspicious clinically palpable breast lesions. In this group of patients, the application of scintimammography with either Tc-MIBI or Tc-anti-CEA Fab' (alone or in combination) offers no additional advantage.