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Purpose: To evaluate whether the post-stress and rest functional parameters, measured by Gated-SPECT, have incremental prognostic value compared with perfusion parameters in predicting cardiac events (CE), in a population of CAD patients with dilated LV., Materials and Methods: A total of 670 consecutive patients (mean age: 62; range 29-86 yrs.) underwent conventional diagnostic 2-day gated-SPECT with 99mTc-tetrofosmin (55% exercise stress test, 45% dip stress): 605 patients (mean age: 62 yrs., range: 34-86 yrs.) had known or suspected CAD, whereas 65 (mean age: 60 yrs, range: 29-80 yrs) had low pre-test likelihood of CAD (<10%), a normal post-stress perfusion scan and no hypertension. Fifty-three percent of CAD patients had a history of MI. Perfusion was analyzed on ungated images using 20 segments scored on a 5-point scale (0=normal, 4=no uptake), while wall thickening was assessed visually on stress/rest end-systolic images using a 4-point score (0=normal, 3=absence of WT). LVEF and volumes were calculated using an automatic algorithm. Post-stress and rest ratio were determined for both end-diastolic and end-systolic volume, while the post-stress LVEF change (d-LVEF) was calculated according to the following formula: (Stress LVEF-rest LVEF)/rest LVEF*100., Results: By using a cutoff value of 126 ml for rest-EDV, and of 68 ml for rest-ESV we found a LV dilation in 129/605 patients (21%). These thresholds were the mean values plus two standard deviations obtained in the control group. 111/129 (86%) were followed up for a mean period of 147.0 months. 83 of 111 (75%) patients had a history of MI and forty three (39%) had undergone surgical revascularizations. During the follow-up, 21 events (5 cardiac deaths, 3 nonfatal MI, 13 late revascularizations) occurred. All post-stress perfusion and functional parameters were more compromised in patients with CE compared with patients without events, but only rest EDV, rest ESV, post-stress ESV and WT-SSS reached statistical significance (201 ml vs 176 ml; p=0.035; 137 ml vs 113 ml; p=0.047; 143 ml vs 117 ml; p=0.034, 19 vs 15; p=0.048, respectively). Multivariate Cox proportional analysis demonstrated that stress ESV added significantly prognostic information over WT-SSS in predicting CE (p=0.046)., Conclusions: Stress ESV has incremental prognostic value compared with wall thickening in predicting CE, in CAD patients with dilated cardiomyopathy. Perfusion parameters failed to show prognostic information in these patients.

Purpose: Non-invasive measurement by peripheral quantitative computed tomography (pQCT) of bone geometry, biomechanics, and mineral content in patients (pts) with primary hyperparathyroidism (PHPT)., Materials and Methods: Total, trabecular and cortical mineral density (totBMD, cortBMD, trab BMD), bone geometrical properties (total area, trabecular area, cortical area, cortical/total area) and cortical thickness as biomechanical parameters, were assessed by pQCT at distal radius in 38 (32 F; 6 M) consecutive patients with PHPT (mean age: 62 yrs; range: 30-77). In a subgroup of 12 patients, bone mineral density (BMD) was also measured by means of dual X-ray absorptiometry (DXA) at the lumbar spine (L2-L4)., Results: Serum biochemical characteristics were: iPTH (269+/-214 pg/ml; range: 107-1438, normal: 30-65), Calcium (11.4+/-1.1 mg/dl; range: 10.6-13.5, normal: 8.1-10.4) and Alkaline Phosphatase (398+/- 392 U/L; range:173-1174, normal: 98-279). Compa-red with 87 healthy age-matched subjects, total, trabecular and cortical bone densities were reduced in all patients (TotBMD: 216+/-92 mg/cm(3) vs ctr 342+/-94, -37%, p<0.05; TrabBMD: 93+/-51 mg/cm(3) vs ctr 140+/-54, -34%, p <0.01; CorBMD: 711+/-178 mg/cm(3) vs ctr 802+/-175, -11%, p<0.02), such as cortical thickness (0.143+/-0.02 cm vs ctr 0.157+/-0.03, -9%, p<0.02). Among geometrical parameters, only cortical/total area was significant different in the two groups (0,29 vs 0.31; p<0.04). A strong correlation was found between peripheral trabecular bone density assessed by pQCT and axial bone mineral density measured by DXA at L2-L4 (r=0.80; p<0.01)., Conclusions: pQCT measurements in PHPT showed: 1) osteopoenia in all bone compartments partly related to age and menopause; 2) reduced cortical density and cortical thickness consistent with "cancellization" of the inner cortex and lower ability of bone to absorb loading forces. DXA measurements showed osteopoenia also at the lumbar spine, a site rich in trabecular bone. PQCT allowing selective assessment of true volumetric cortical and trabecular bone density such as bone geometry, is proposable in clinical practice, in order to evaluate presurgical bone "status" and to monitor the response to parathyroidectomy.

Aim: Non-invasive assessment of bone geometry, biomechanics, and mineral content in postmenopausal women by peripheral quantitative Computed Tomography (pQCT)., Material and Methods: Total, trabecular and cortical mineral density (totBMD, cortBMD, trabBMD), and the geometrical (total area, trabecular area, cortical area) and biomechanical properties of bone (strength-strain index, cortical thickness) were assessed in 93 consecutive post-menopausal women (mean age: 63+/-7 yrs; age at menopause: 49+/-6 yrs; years since menopause: 14+/-9 yrs) by pQCT at the ultradistal radius of non-dominant forearm., Results: Compared with 50 healthy women at peak of bone mass, volumetric total, trabecular and cortical bone densities were significantly reduced in postmenopausal subjects (TotBMD: 318+/-106 mg/cm3 vs ctr 442+/-100, -28%, p<0.001; TrabBMD: 117+/-59 mg/cm3 vs ctr: 203+/-47, -42%, p<0.001; CorBMD: 764+/-159 mg/cm3 vs 921+/-111, -17%, p<0.001). The bone loss was greater in trabecular bone. Cortical area (0.7+/-0,1 cm2 vs ctr: 0.8+/-0.1, -12.5%, p<0.001), cortical thickness (0.151+/-0.02 cm vs ctr: 0.169+/-0.03, -11%, p<0.001), and strength-strain index (686+/-207 mm3 vs ctr: 883+/-165, -22%, p<0.001) were significantly lower in post-menopausal women in comparison with the controls. Years since menopause and age showed a significant negative correlation with bone mineral densities and biomechanical parameters., Conclusions: In post-menopausal women pQCT showed: 1) osteopoenia in all bone compartments, greater at the trabecular level, related to age and years since menopause; 2) reduced cortical density and cortical thickness, consistent with a reduced ability of bone to absorb loading forces; 3) reduced strength-strain index, indicative of inability to adapt to mechanical use and augmented risk for fracture. We conclude that pQCT is a valuable tool for measuring the true volumetric mineral density and the geometrical and biomechanical indexes of bone, which could be proposed in current clinical practice for the assessment of osteoporosis.

Purpose: Noninvasive assessment of bone mineral density, geometrical and biomechanical properties in premenopausal women with dietary intake of phytoestrogens and comparison of these parameters with those of age-matched female subjects with "Mediterranean" dietary intake lacking in these substances., Material and Methods: Volumetric cortical, trabecular and total mineral density and bone geometrical properties were evaluated in 15 female subjects with phytoestrogens dietary intake. Peripheral quantitative Computed Tomography (pQCT) was used to make measurements at the distal radius of the nondominant forearm. Fifteen age-matched subjects with "Mediterranean" dietary intake were chosen as a control group. Cross-sectional area (Total A), trabecular area (TA), cortical area (CA), cortical thickness (CThk) and strength strain index (SSI) were assessed as biomechanical parameters., Results: Daily consumption of phytoestrogens was significatively different in the two groups (phy: 17.45 mg/die vs ctr: 0.35; p < 0.0005), while calcium intake was similar (phy: 652 mg/die vs ctr: 650). Total (0.460 g/cm3 vs ctr: 0.433) and trabecular (phy: 0.209 g/cm3 vs ctr: 0.189) bone mineral densities, such as SSI (phy: 925 mm3 vs ctr: 894) values, were higher in women with dietary intake of phytoestrogens, in comparison with the relative controls, but not significantly (p = ns). Among geometrical parameters, total area and cortical area were tendential in women with a vegetarian diet while cortical thickness was the same in both groups., Conclusions: pQCT showed higher bone mineral density (total and trabecular) and SSI values in premenopausal women with dietary intake of phytoestrogens. Despite the lack of statistical significance, these preliminary results, should further support the few literature findings about the potential role of phytoestrogens consumption in preventing trabecular bone loss. However, further studies are warranted to evaluate definitively the efficacy of phytoestrogens in preventing postmenopausal osteoporosis.

Introduction: Bone integrity and mineral status were studied with a noninvasive method in uremic patients with severe secondary hyperparathyroidism undergoing maintenance hemodialysis., Material and Methods: Volumetric cortical and trabecular mineral density (cBMD, tBMD) and bone geometrical properties were evaluated in 16 patients (11 women and 5 men) candidate to parathyroidectomy. Peripheral quantitative Computed Tomography (pQCT) was used to make measurements at the distal radius of the nondominant forearm. Thirty-two age-matched healthy subjects were chosen as a control group. Cortical area (CA), cross-sectional area (Total A), cortical thickness (CThk) and stress strain index (SSI) were assessed as biomechanical parameters. Serum intact PTH levels were assessed with a radioimmunoassay method (IRMA)., Results: Both cBMD and tBMD were decreased in all patients and the difference was more significant in women (p < .0004 and p < .009) than in the smaller group of men (p < .01 and p < .01). Serum PTH levels correlated negatively with cBMD (r = .52; p < .01), CThk (r = .51; p < .04), CA (r = .52; p < .03) and SSI (r = .54; p < .02), as well as tBMD (r = .34), though not significantly. Dialysis duration did not significantly correlate with cBMD (r = .33), tBMD (r = .20), CA (r = .31), CThk (r = .40) and SSI (r = .35). As for geometrical and biomechanical parameters, CA, CThk and SSI were significantly different in both male and female uremic patients in comparison with the relative controls. Bone quantitative analysis and three-dimensional (3D) representation with the paraboloid revolution model also demonstrated osteopenia., Conclusions: pQCT shows significant cortical and trabecular osteopenia in uremic patients with severe secondary hyperparathyroidism. Osteopenia is associated with geometrical and mechanical impairment with consequently increased bone fragility and thus a higher risk of fracture. Prolonged PTH hyperexpression seems to be mainly associated with intracortical porosity and cortical-endosteal resorption. Bone quantitative analysis and 3D representation provide rapid automated information on the cortex mineral status.

Introduction: Gated SPECT using 99mTc-labeled flow tracers provides simultaneous assessment of global and regional myocardial function., Purpose: To investigate whether studying regional wall thickening after stress and at rest provides additional diagnostic information in coronary artery disease patients., Methods: We examined 61 consecutive patients (40 men) who underwent conventional diagnostic dual day stress/rest Gated SPECT using a dual head SPECT camera, following injection of 925 MBq of 99mTc-Tetrofosmin. The mean age of these patients was 61 years (range: 23-73); 28 patients had a history of myocardial infarction. Perfusion was analyzed on both ungated and end-diastolic images using 20 segments scored on a 5-point scale (0 = normal, 4 = no uptake), while wall thickening and motion were assessed visually on stress/rest end-systolic images using a 4-point score (0 = normal, 3 = no wall thickening/motion). Twenty eight patients underwent coronary angiography., Results and Discussion: 14/61 (23%) patients showed no segmental defects, while fixed equivocal defects, with preserved wall thickening, in 10/61 (16%) patients were considered artifactual. 11/61 (18%) showed true fixed defects. The remaining 26 patients showed al least one reversible defect. 14/61 (23%) patients with post-stress wall thinning and normal rest wall thickness, were considered stunned. The stunned subgroup showed a significant post-stress reduction in left ventricular ejection fraction. Finally, analyzing 1220 segments, we found an excellent agreement (k = .697) between the segmental score obtained by end-diastolic and ungated post-stress images: in fact, comparing the two sets of images, diagnostic accuracy was not significantly different. However the number of segments with fixed defects and normal wall thickening was lower with end-diastolic perfusion images than with ungated images, probably due to attenuation artifacts. This suggests a better accuracy of the former in the evaluation of regional myocardial perfusion., Conclusions: Although stress end-diastolic images do not seem to significantly improve diagnostic perfusion accuracy compared to ungated acquisitions, the simultaneous assessment of stress-rest wall thickening permits better characterization of a coronary artery disease population.

Introduction: We report our personal experience in patients with biochemical hyperthyroidism and no nodules, studying the correlations between antithyroid autoantibodies titers, thyroid function and clinical symptoms., Material and Methods: We examined 93 patients (13 men and 80 women, mean age: 44.6 years, range: 25-68 years) referred for suspected hyperthyroidism. Thyroid 99mTc scintigraphy was performed and the 20 minutes' uptake index (UI) calculated: all these patients had a scintigraphic pattern of normal or enlarged thyroid with homogeneous radiotracer uptake. The presence and titer of antiperoxidase (TPO) and anti-TSH receptor antibodies (TRAB), FT3, FT4, TSH were assayed. Based on the results, the patients were divided into 4 subgroups: A (high TRAB/high TPO, no. 17), B (low TRAB/high TPO, no. 15), C (high TRAB/low TPO, no. 35), D (low TRAB/low TPO, no. 26). The incidence of hyperthyroidism symptoms was 94% in Group A, 40% in Group B, 89% in Group C, 50% in group D., Results: UI significantly correlated with FT3 (p < .001), FT4 (p < .01) and TRAB (p < .01) titers. FT3 and UI average values were significantly higher in Group A and Group C patients (high TRAB) than in Group B and Group D patients (low TRAB) (p < .01); these parameters were significantly higher also in Group A than in Group B patients (p < .05 for FT3 and p < .03 for UI, respectively). Mean intergroup TSH values did not differ (p = ns) and anti-TPO antibodies did not correlate with FT3, FT4 and TSH titers., Conclusions: UI behaved as a good marker of hyperthyroidism in all patients and TRAB correlated well with organ function and the clinical picture; however, about 18% of patients exhibited no antibody production. No correlation was found between TPO and thyroid function. The lack of antithyroid antibodies seems to indicate a better clinical course for hyperthyroidism. The patients without TRAB and/or with high anti-TPO titers may follow different clinical courses and need a regular follow-up.