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1.
Clin Nephrol ; 59(1): 59-63, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12572933

RESUMO

AIMS: The reversibility of extraskeletal calcifications in dialysis patients is an important and unresolved issue. Although periarticular calcifications have been shown to be reversible, little data are available on vascular or parenchymal calcifications. CASE HISTORY: A patient on maintenance hemodialysis with severe hyperparathyroidism, hypercalcemia and hyperphosphatemia was admitted to undergo parathyroidectomy. A preoperative total body bone scintigraphy was performed to better evaluate a lytic lesion in the pelvis, the histology of which proved to be a "brown tumor". The scan showed the typical findings of renal osteodystrophy, but also a diffuse extra-skeletal uptake of bone tracer in the lungs, kidneys, femoral arteries and myocardium. After surgery, good control of serum calcium, phosphate (Ca x P product < 50 mg2/dl2) and PTH levels was maintained during 4 years of follow-up. Bone scans were repeated after 2 and 4 years, showing marked improvement of periarticular uptake at the ends of long bones. Extraosseous calcium deposition was still markedly evident, but progressively decreased (at 4 years: heart -36%, lungs -18%). CONCLUSION: In this dialysis patient, extraskeletal calcification of visceral organs (particularly in the heart and the lungs) due to prolonged hypercalcemia and hyperphosphatemia was partially reversible by parathyroidectomy followed by good long-term control of serum phosphate and calcium.


Assuntos
Calcinose/etiologia , Calcinose/cirurgia , Cardiopatias/etiologia , Cardiopatias/cirurgia , Hiperparatireoidismo/etiologia , Hiperparatireoidismo/cirurgia , Pneumopatias/etiologia , Pneumopatias/cirurgia , Paratireoidectomia , Indução de Remissão , Diálise Renal/efeitos adversos , Adulto , Calcinose/sangue , Cálcio/sangue , Feminino , Seguimentos , Cardiopatias/sangue , Humanos , Hiperparatireoidismo/sangue , Pneumopatias/sangue , Fosfatos/sangue , Fatores de Tempo
2.
Radiol Med ; 103(3): 233-41, 2002 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-11976620

RESUMO

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.


Assuntos
Densidade Óssea/fisiologia , Osteoporose Pós-Menopausa/diagnóstico por imagem , Rádio (Anatomia)/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Fenômenos Biomecânicos , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/fisiopatologia , Pós-Menopausa/fisiologia , Rádio (Anatomia)/fisiologia
4.
Nucl Med Commun ; 22(6): 685-93, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11403181

RESUMO

Several studies have shown the accuracy of gated single photon emission computed tomography (SPECT) using thallium-201 and technetium tracers in the assessment of myocardial perfusion and function. Gated SPECT has been successfully utilized to detect post-stress left ventricular ejection fraction (LVEF) reduction resulting from post-ischemic stunning in patients with coronary obstruction. The aim of this study was to evaluate whether the post-stress LVEF impairment could be related to the post-stress end-systolic ventricular dilation resulting from post-ischemic endocardial stunning. Two hundred and eighty-two consecutive patients were studied by conventional diagnostic 2 day stress/rest gated SPECT following injection of 925 MBq of 99mTc-tetrofosmin using a dual-headed SPECT camera. One hundred and forty-seven of these patients (52%) showed reversible perfusion defects, 69 (24%) permanent defects and the remaining 66 (24%) had normal perfusion. One hundred and thirty-eight of these patients had a history of myocardial infarction (MI) and 19% underwent coronary angiography without an intervening cardiac event. Perfusion was analysed on ungated images using 20 segments scored on a five-point scale (0, normal; 4, no uptake), while wall thickening (WT) was assessed visually on stress/rest end-systolic images using a four-point score (0, normal; 3, absence of WT). LVEF and volumes were calculated using an automatic algorithm. The post-stress and rest ratios were determined for both end-diastolic (EDV) and end-systolic (ESV) volume. Normal values for all these parameters were obtained using data from 149 patients with a low likelihood (<5%) of coronary artery disease (CAD). In 50 of the 147 (34%) of patients with reversible perfusion defects, post-stress LVEF was >5% lower than rest values (stunned group), while the remaining 97 patients did not show a significant LVEF change (group 2A). The percentage of patients who developed exercise-induced angina, the percentage of patients who underwent coronary angiography and the segmental summed perfusion and WT scores were significantly higher in the stunned group compared with group 2A. Only ESV increased significantly post-stress, and this increase occurred only in stunned patients. Both EDV and ESV ratios were significantly higher in the stunned group compared with normal controls (P=0.008 and P<0.000001, respectively) and with the subgroup 2A (P=0.011 and P<10(-12), respectively). The ESV stress/rest ratio correlated significantly with the summed WT difference score by univariate analysis in stunned patients. It can be concluded that the post-stress ESV dilation, obtained by stress/rest gated SPECT, seems to be due to endocardial post-ischemic stunning. The stunned patients showed more severe clinical, angiographic, perfusion and function parameters.


Assuntos
Teste de Esforço/métodos , Miocárdio Atordoado/fisiopatologia , Função Ventricular Esquerda/fisiologia , Idoso , Dor no Peito/diagnóstico por imagem , Angiografia Coronária , Circulação Coronária/fisiologia , Doença das Coronárias/diagnóstico por imagem , Feminino , Imagem do Acúmulo Cardíaco de Comporta , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Volume Sistólico , Tálio , Tomografia Computadorizada de Emissão de Fóton Único , Vasodilatação/fisiologia
5.
J Nucl Med ; 41(10): 1597-602, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11037986

RESUMO

UNLABELLED: The aim of this study was to use gastroesophageal and pulmonary scintigraphy to evaluate the prevalence of gastroesophageal reflux and airway involvement among patients with posterior laryngitis. METHODS: The study included a total of 201 patients (131 females, 70 males; age range, 15-77 y; mean age +/- SD, 49 +/- 16 y). All patients had posterior laryngitis documented by laryngoscopy and symptoms such as a dry cough, painful swallowing, and hoarseness. A control population of 20 healthy volunteers (13 females, 7 males; age range, 19-74 y; mean age, 53 +/- 13 y) was also evaluated. After a 12-h fast, all subjects underwent gastroesophageal scintigraphy through administration of 300 mL orange juice labeled with 185 MBq 99mTc-sulfur colloid. After 18 h, planar anteroposterior thoracic images were acquired with the subjects supine. RESULTS: Sixty-seven percent of patients (134/201) had scans positive for gastroesophageal reflux; of these, 30 (22%) had distal reflux and 104 (78%) had proximal reflux. In addition, the scans of 31 patients were positive for proximal reflux-associated pulmonary uptake. The frequency, duration, and degree of reflux episodes were significantly greater in patients with proximal reflux than in patients with distal reflux (P < 0.001). The 67 patients in whom reflux was not detected had diseases or reflux-associated cofactors that could account for laryngeal symptoms. No statistically significant difference in symptoms or esophageal motility parameters could be identified among the patient groups, but patients with proximal reflux had significantly prolonged gastric emptying times compared with healthy volunteers. CONCLUSION: Most patients with posterior laryngitis had detectable proximal gastroesophageal reflux. Exposure of the proximal part of the esophagus to acid, by setting the stage for microaspiration of gastric material into the larynx, remains a major cause of damage to the laryngeal mucosa. Slowed gastric emptying may be a predisposing factor. Moreover, symptoms such as a dry cough, painful swallowing, or hoarseness may not be reliable predictors of the presence of gastroesophageal reflux or of associated airway involvement.


Assuntos
Refluxo Gastroesofágico/diagnóstico por imagem , Laringite/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pneumonia Aspirativa/diagnóstico por imagem , Coloide de Enxofre Marcado com Tecnécio Tc 99m , Estudos de Casos e Controles , Esôfago/diagnóstico por imagem , Feminino , Esvaziamento Gástrico , Refluxo Gastroesofágico/complicações , Humanos , Laringite/etiologia , Masculino , Pessoa de Meia-Idade , Pneumonia Aspirativa/etiologia , Cintilografia , Compostos Radiofarmacêuticos , Estômago/diagnóstico por imagem
7.
Radiol Med ; 99(4): 250-7, 2000 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-10884825

RESUMO

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.


Assuntos
Densidade Óssea/fisiologia , Dieta Vegetariana , Estrogênios não Esteroides/administração & dosagem , Isoflavonas , Osteoporose/diagnóstico por imagem , Pré-Menopausa/fisiologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Animais , Fenômenos Biomecânicos , Registros de Dieta , Ovos , Feminino , Humanos , Região do Mediterrâneo , Leite , Osteoporose/prevenção & controle , Fitoestrógenos , Preparações de Plantas , Plantas , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiologia , Tomografia Computadorizada por Raios X/estatística & dados numéricos
9.
Acta Cardiol ; 55(1): 9-15, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10707753

RESUMO

UNLABELLED: We studied the effects of glucose, insulin, and KCl infusion (GIK), on regional myocardial perfusion and function by 99m-Tc-tetrofosmin-gated SPECT. METHODS: We studied 21 male patients with their first uncomplicated acute myocardial infarction (AMI). All patients underwent a rest and submaximal stress before and after 24-hour infusion of GIK-solution (group A) or saline solution (group B). RESULTS: Group A showed better stress tolerance and ischaemic threshold improvement after GIK infusion whilst no statistical differences were found between basal and post-infusion test in group B. At first the stress test in group A, of the 192 segments analysed, 52 (27%) showed reversible perfusion defect. In group B, of 144 segments analysed, 31 (21%) showed reversible perfusion defect. A post-infusion analysis in group A showed a post-GIK end-diastolic significant count improvement in 21 segments, and a post-GIK end-systolic count improvement in 22 segments. In group B, perfusion increase was observed only in 4 segments, whilst systolic thickening increase was observed only in 1 segment. CONCLUSION: These data demonstrate the efficacy of GIK infusion to improve regional myocardial perfusion and function mainly in segments adjacent to the recently infarcted area.


Assuntos
Soluções Cardioplégicas/administração & dosagem , Coração/efeitos dos fármacos , Infarto do Miocárdio/tratamento farmacológico , Adulto , Idoso , Distribuição de Qui-Quadrado , Angiografia Coronária/estatística & dados numéricos , Método Duplo-Cego , Eletrocardiografia , Teste de Esforço/métodos , Teste de Esforço/estatística & dados numéricos , Glucose/administração & dosagem , Coração/fisiopatologia , Humanos , Insulina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Compostos Organofosforados , Compostos de Organotecnécio , Potássio/administração & dosagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos
10.
Minerva Med ; 91(11-12): 267-74, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11253707

RESUMO

BACKGROUND: To review our experience in infectious diseases diagnosis, using a simple labelling technique. METHODS: We made 101 scans in 91 patients with suspected infectious diseases confirmed by clinical, histologic or cultural specimens; a clinical or instrumental follow-up was available for every patient. Patients were divided into four subgroups: A: Inflammatory Bowel Diseases; B: Septic Syndromes; C: Bone diseases; D: Others. We used 99mTc-HMPAO in 80 scans and 111In in 21. In 20/80 frozen and stored HMPAO was used. RESULTS: 99mTc-HMPAO frozen and stored labelling yield was: 60%(SD15%), 99mTcHMPAO: 62(12)(p n.s.), 111In 75%(10%), (p < 0.05). Frozen-stored HMPAO was sterile and apyrogen. 27 had positive scan without leukocytosis or neutrophilia. No correlation between leukocytosis or neutrophilia and yield was observed. Transit lung times ranged between 14-16 min without differences among three radiopharmaceuticals. In each Group and in the sample as a whole True Positive, False Positive, True Negative, False Negative, Sensitivity, Specificity and Accuracy, were calculated. In Group B and in the sample as a whole Predictive Positive Value and Negative Predictive Value were also evaluated. CONCLUSIONS: Labelling yields and "viability" were good using the three radiopharmaceuticals; labelling procedure was simple and safe. Accuracy PPV, NPV, cost-effectiveness were good; 111In is the choice for diagnosis of bone and joint infections. Frozen-stored HMPAO should be introduced as a cost-saving labelling procedure in practice.


Assuntos
Doenças Ósseas Infecciosas/diagnóstico por imagem , Radioisótopos de Índio , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Leucócitos , Compostos Organometálicos , Oxiquinolina/análogos & derivados , Compostos Radiofarmacêuticos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico por imagem , Tecnécio Tc 99m Exametazima , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Inflamação/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Sensibilidade e Especificidade
11.
Radiol Med ; 100(6): 480-3, 2000 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-11307510

RESUMO

PURPOSE: To evaluate the clinical effectiveness of a simplified dosimetric approach to the iodine-131 treatment of hyperthyroidism due to Graves' disease or uninodular and multinodular toxic goiter. MATERIAL AND METHODS: We enrolled 189 patients with biochemically confirmed hyperthyroidism and performed thyroid ultrasonography and scintigraphy obtaining the diagnosis of Graves' disease in 43 patients, uninodular toxic goiter in 57 patients and multinodular toxic goiter in 89 patients. In 28 patients we found cold thyroid nodules and performed fine-needle aspiration with negative cytology for thyroid malignancy in all cases. Antithyroid drugs were stopped 5 days till radioiodine administration and, if necessary, restored 15 days after the treatment. Radioiodine uptake test was performed in all patients and therapeutic activity calculated to obtain a minimal activity of 185 MBq in the thyroid 24 hours after administration. The minimal activity was adjusted based on clinical, biochemical and imaging data to obtain a maximal activity of 370 MBq after 24 hours. RESULTS: Biochemical and clinical tests were scheduled at 3 and 12 months posttreatment and thyroxine treatment was started when hypothyroidism occurred. In Graves' disease patients a mean activity of 370 MBq (distribution 259-555 MBq) was administered. Three months after treatment and at least 15 days after methimazole discontinuation 32 of 43 (74%) patients were hypothyroid, 5 of 43 (11%) euthyroid and 6 of 43 (15%) hyperthyroid. Three of the latter were immediately submitted to a new radioiodine administration while 32 hypothyroid patients received thyroxine treatment. One year after the radioiodine treatment no patient had hyperthyroidism; 38 of 43 (89%) were on a replacement treatment while 5 (11%) remained euthyroid. In uni- and multinodular toxic goiter a mean activity of 444 MBq (distribution 259-555 MBq) was administered. Three months posttreatment 134 of 146 (92%) patients were euthyroid and 12 of 146 (8%) patients hyperthyroid. Two patients were immediately submitted to a new radioiodine administration. One year posttreatment 142 of 146 (97%) patients were euthyroid while only 4 of 146 (3%) patients showed TSH levels above the normal range. Only 2 of them required thyroxine treatment. CONCLUSIONS: The simplified dosimetric method illustrated in our paper is very effective in clinical practice because it permits to avoid resorting to sophisticated but also imprecise quantitative methods. Hypothyroidism should not be considered as a major collateral effect of radioiodine treatment, particularly in Graves' disease. In fact, the pathogenesis of the disease requires an ablative treatment with both surgery and radioidine treatment and the control of hyperthyroidism and the prevention of relapse are the major clinical targets. Vice versa, hypothyroidism was very uncommon in uni- and multinodular toxic goiter when our dosimetric approach was applied.


Assuntos
Hipertireoidismo/radioterapia , Radioisótopos do Iodo/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Bócio Nodular/radioterapia , Doença de Graves/radioterapia , Humanos , Hipotireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Radioterapia/efeitos adversos , Dosagem Radioterapêutica , Fatores de Tempo
12.
Cardiologia ; 44(9): 817-23, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10609391

RESUMO

BACKGROUND: The presence of tissue viability is of great importance in the prognostic work-up of patients recovering from acute myocardial infarction. However, uncertainty still exists concerning the optimal tool for its assessment. The present study was undertaken in order to compare low-dose dobutamine echocardiography and rest-redistribution thallium SPECT for predicting late improvement of regional left ventricular function after acute myocardial infarction. METHODS: Fifteen patients undergoing coronary angiography, low-dose dobutamine echocardiography and rest-redistribution thallium SPECT after thrombolyzed anterior acute myocardial infarction were studied. A 3 month follow-up echocardiogram was performed in all patients and 9 underwent coronary revascularization. RESULTS: A significant (> or = 70%) residual stenosis of the infarct-related artery was present in 14 patients, whilst a total occlusion was observed in 1. At 3 month follow-up, 41% of the dyssynergic segments improved. The sensitivity, specificity and accuracy for late wall motion improvement was 61, 89 and 77% for low-dose dobutamine echocardiography and, respectively, 76, 45 and 58% for rest-redistribution thallium SPECT. Tissue viability was detected in 65 and 31% of dyssynergic segments by rest-redistribution thallium SPECT and low-dose dobutamine echocardiography, respectively (p < 0.001). The agreement between the two techniques was 48%. CONCLUSIONS: Low-dose dobutamine echocardiography is more accurate than rest-redistribution thallium SPECT for predicting 3 month wall motion improvement in patients with acute anterior myocardial infarction, mainly due to its significantly better specificity.


Assuntos
Cardiotônicos , Dobutamina , Ecocardiografia/métodos , Coração/fisiopatologia , Infarto do Miocárdio/diagnóstico por imagem , Compostos Radiofarmacêuticos , Radioisótopos de Tálio , Sobrevivência de Tecidos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Cardiotônicos/administração & dosagem , Angiografia Coronária , Dobutamina/administração & dosagem , Feminino , Seguimentos , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Prognóstico , Compostos Radiofarmacêuticos/administração & dosagem , Sensibilidade e Especificidade , Radioisótopos de Tálio/administração & dosagem
13.
Nuklearmedizin ; 38(5): 169-71, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10488486

RESUMO

A 66-year-old man affected by polyostotic form of fibrous dysplasia in consequence of worsening of lower extremity bone pain aggravated by walking and concomitant increase of serum alkaline phosphatase and osteocalcin, was subjected first to a radionuclide study. Bone scan demonstrated a pathological uptake of the radiotracer in the craniofacial bones, right scapula, left and right posterior ribs, right hemipelvis and lower extremities confirming the diagnosis but establishing especially the extent of bone involvement, greater than expected on the basis of symptoms and X-ray findings, underlying the importance of nuclear medicine imaging in the assessment and follow-up of this rare disease.


Assuntos
Osso e Ossos/diagnóstico por imagem , Displasia Fibrosa Poliostótica/diagnóstico por imagem , Compostos Radiofarmacêuticos , Medronato de Tecnécio Tc 99m , Idoso , Diagnóstico Diferencial , Humanos , Masculino , Radiografia , Cintilografia
14.
Radiol Med ; 97(4): 229-35, 1999 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-10414254

RESUMO

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.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/diagnóstico por imagem , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiopatologia , Tomografia Computadorizada por Raios X , Uremia/complicações , Adulto , Idoso , Fenômenos Biomecânicos , Densidade Óssea , Distúrbio Mineral e Ósseo na Doença Renal Crônica/complicações , Distúrbio Mineral e Ósseo na Doença Renal Crônica/patologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/patologia , Índice de Gravidade de Doença
15.
G Ital Cardiol ; 29(4): 411-7, 1999 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-10327319

RESUMO

BACKGROUND: The aim of this study was to evaluate the impact of attenuation correction (AC) on the diagnostic accuracy of conventional stress/red thallium SPECT studies. METHODS: We studied 60 consecutive patients (36 males) who underwent conventional diagnostic stress/red study with and without AC (NAC) using a dual-head SPECT camera (Vertex ADAC) with a 153Gd source. The mean age of these patients was 60 years (30-80) and 29 of the subjects had a history of MI. Reconstructed images were visually analyzed using 20 segments scored on a 5-point scale (0 = normal, 4 = no uptake). Diagnostic accuracy was evaluated in 24 consecutive patients who underwent coronary angiography. Polar plots from each of the four reconstructed data sets per patient were normalized on the maximum and quantified using a nine segment model. RESULTS: The comparison between the segmental stress score obtained with and without AC showed agreement in 1057 out of 1200 (88%) segments analyzed, K statistic value = 0.67. The number of fixed defects was significantly lower after AC. The diagnostic accuracy, evaluated in 24 patients (480 segs), was not significantly different between AC and NAC analysis (80 vs 84% respectively). CONCLUSIONS: AC seems to reduce the number of fixed defects due to attenuation artefacts without improving diagnostic accuracy, probably because of the low number of subjects submitted to angiography and of the interpreting bias due to the expertise of the operators. In fact, in the rather small group of patients evaluated, no improvement in diagnostic accuracy was observed, probably because several attenuation defects were not considered pathological due to operator expertise.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária , Feminino , Câmaras gama , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos
16.
Radiol Med ; 97(1-2): 48-53, 1999.
Artigo em Italiano | MEDLINE | ID: mdl-10319099

RESUMO

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.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Imagem do Acúmulo Cardíaco de Comporta , Circulação Coronária , Doença das Coronárias/fisiopatologia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos
17.
G Ital Cardiol ; 29(2): 143-8, 1999 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-10088069

RESUMO

UNLABELLED: Gated SPECT using Tc-99m-labeled flow tracers provides simultaneous assessment of global and regional myocardial perfusion and function. The aim of this study was to evaluate whether regional wall thickening (WT) obtained after stress and at rest makes it possible to identify and analyze a subgroup of post-ischemic stunned patients. METHODS: We studied 20 patients (18 males) who underwent conventional diagnostic dual-day stress/rest Gated SPECT following injection of 925 MBq of 99mTc-tetrofosmin using a dual-head SPECT camera (Vertex ADAC). The mean age of these patients was 59 years (38-71) and 10 of them had a history of previous acute myocardial infarction (AMI). Perfusion was analyzed on ungated images using 20 segments scored on a 5-point scale (0 = normal, 4 = no uptake), while WT and motion were assessed visually on stress/rest end-systolic images using a 4-point score (0 = normal, 3 = absence of WT/motion). Left ventricular ejection fraction (LVEF) and volumes were calculated. All patients underwent coronary angiography. RESULTS: All patients showed at least one reversible defect with post-stress WT reduction and normal rest WT. The stunned group showed a significant post-stress reduction of LVEF and a statistically non-significant increase of end systolic volume (ESV). A good correlation was observed between global perfusion and WT score both at stress and rest conditions; LVEF showed a significant inverse correlation with global post-stress and rest perfusion and WT score. ESV and the global perfusion stress/rest score showed a good correlation, while end-diastolic volume did not correlate. In 44% of the segments with fixed defects, there was a normal WT and normal coronary-related vessel (false positives); 28% of reversible segments showed a post-stress pathological WT and five of them a rest pathological WT. CONCLUSIONS: The gated SPECT myocardial perfusion evaluation allowed us to analyze a subgroup of post-stress stunned coronary artery disease patients. The post-stress LVEF reduction in this population seems to be due to the increase of end-systolic volume caused by endocardial ischemia. The stunned segments showed severe perfusion defects.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Coração/diagnóstico por imagem , Miocárdio Atordoado/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Angiografia Coronária , Doença das Coronárias/fisiopatologia , Eletrocardiografia , Teste de Esforço/métodos , Feminino , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio Atordoado/fisiopatologia , Compostos Organofosforados , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos
18.
J Nucl Med ; 40(1): 77-84, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9935061

RESUMO

UNLABELLED: Esophageal transit scintigraphy seems to be a valid methodology to assess impaired esophageal motility in early stages of disease. The purpose of this study was to discriminate patients with primary Raynaud's phenomenon (RP) and patients with systemic sclerosis (SSc) from healthy subjects by esophageal scintigraphy with a semisolid meal. METHODS: We studied 32 patients with primary RP, 18 with SSc and 13 healthy subjects. Dysphagia, acid regurgitation and heartburn were scored. After an overnight fast, all subjects underwent esophageal scintigraphy, using a semisolid orally ingested bolus (10 mL apple puree) labeled with 99mTc-sulfur colloid. Esophageal transit and emptying time and integral value were evaluated with the subjects in the upright (sitting) and supine positions. Transit time was defined as the time from the entry of 50% of radioactivity into the upper esophagus until the clearance of 50% of the bolus from the whole esophagus. Emptying time was defined as the time from the entry of 50% of radioactivity into the upper esophagus, until the clearance of 100% of the bolus from the whole esophagus. Integral value was defined as the total counts under the time-activity curve normalized to the maximum. RESULTS: Esophageal transit and emptying time and integral value, evaluated in both positions, were significantly higher in patients with SSc than in healthy subjects and than in patients with RP. Moreover, patients with RP had all three parameters, assessed in supine position, significantly longer compared to healthy subjects. Clinical scores regarding dysphagia, acid regurgitation and heartburn were not significantly different between patients with RP and SSc. CONCLUSION: Esophageal transit and emptying time and integral value appear to be able to discriminate patients with primary RP from patients with SSc and patients with RP from healthy subjects, suggesting an early mild esophageal dysfunction in RP.


Assuntos
Transtornos da Motilidade Esofágica/diagnóstico por imagem , Esôfago/diagnóstico por imagem , Doença de Raynaud/complicações , Escleroderma Sistêmico/complicações , Adulto , Idoso , Deglutição , Transtornos da Motilidade Esofágica/etiologia , Transtornos da Motilidade Esofágica/fisiopatologia , Esôfago/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peristaltismo , Cintilografia , Compostos Radiofarmacêuticos , Coloide de Enxofre Marcado com Tecnécio Tc 99m
19.
Minerva Gastroenterol Dietol ; 45(2): 107-17, 1999 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-16498321

RESUMO

BACKGROUND: Esophageal transit scintigraphy seems to be a valid methodology to assess impaired esophageal motility, also in the early stages of disease. AIM: To discriminate patients with primary Raynaud's phenomenon (RPh and patients with systemic sclerosis (SSc) from healthy subjects, by esophageal scintigraphy with a semisolid meal. METHODS: Thirty-two patients with primary RPh, 18 patients with SSc and 13 healthy subjects have been studied. Symptoms as dysphagia, acid regurgitation and heartburn, were scored. After an overnight fast, all subjects underwent esophageal scintigraphy, using a semisolid orally ingested bolus (10 ml apple purèe) labelled with 99mTc-sulfur colloid. Esophageal transit and emptying time and integral value were evaluated with the subjects in the upright (sitting) and in the supine position. Transit time was defined as the time from entry of 50% of radioactivity into the upper esophagus, up to the clearance of 50% of the bolus from the whole esophagus. Emptying time was defined as the time from the entry of 50% of radioactivity into the upper esophagus, up to the clearance of 100% of the bolus from the whole esophagus. Integral value was defined as the total count under the time/activity curve normalized to the maximum. RESULTS: Esophageal transit and emptying time, and integral value, evaluated in both positions, were significantly higher in patients with SSc than in healthy subjects and than in patients with RPh. Moreover, patients with RPh had all three parameters, assessed in supine position, significantly longer compared to healthy subjects. Clinical scores regarding dysphagia, acid regurgitation and heartburn were not significantly different between patients with RPh and SSc. CONCLUSIONS: Esophageal transit and emptying time and integral value seem to be able to discriminate well patients with primary RPh from patients with SSc and patients wih RPh from healthy subjects, suggesting an early mild esophageal dysfunction in RPh.

20.
Radiol Med ; 95(3): 188-92, 1998 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-9638164

RESUMO

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.


Assuntos
Autoanticorpos/sangue , Hipertireoidismo/imunologia , Glândula Tireoide/imunologia , Adulto , Idoso , Feminino , Humanos , Hipertireoidismo/sangue , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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