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Biomedical subjects

M Salvatore

Publications and source records attributed to M Salvatore.

At least 91 records · Page 5Linked to original sources
PubMed1998

Combined evaluation of rest-redistribution thallium-201 tomography and low-dose dobutamine echocardiography enhances the identification of viable myocardium in patients with chronic coronary artery disease.

The purpose of this study was to evaluate whether combined evaluation by discriminant analysis of rest-redistribution thallium-201 tomography and low-dose dobutamine echocardiography enhances the accuracy in identifying viable myocardium in patients with chronic coronary artery disease. Rest-redistribution 201Tl has high sensitivity but low specificity in identifying viable myocardium, while the opposite is true for low-dose dobutamine echocardiography. Forty-six patients underwent low-dose dobutamine echocardiography and rest-redistribution 201Tl tomography on the same day. Rest echocardiography was repeated at least 30 days (mean 40+/-20) after myocardial revascularization. Discriminant analysis was applied to the results of 201Tl tomography and dobutamine echocardiography to classify a/dyskinetic segments as viable or non-viable. In 92 a/dyskinetic segments that were revascularized, rest-redistribution 201Tl tomography yielded an accuracy of 75%, while the accuracy of dobutamine echocardiography was 70% (P<0.05). When discriminant analysis was used, the combined evaluation gave an accuracy of 83% (P<0.05 vs both tests). These findings demonstrate that low-dose dobutamine echocardiography and 201Tl imaging are useful and complementary techniques for identifying viable myocardium in patients with chronic coronary artery disease. Combined evaluation by discriminant analysis significantly improves accuracy, although the cost-effectiveness of such an approach remains to be determined.

Adrenergic beta-Agonists↗
PubMed1998

Cerebral blood flow in spinocerebellar degenerations: a single photon emission tomography study in 28 patients.

We used single photon emission tomography to study regional cerebral perfusion in patients with different forms of spinocerebellar degeneration: 6 patients with Friedreich's ataxia (FA), 6 with early-onset cerebellar ataxia with retained tendon reflexes (EOCA), 5 with autosomal dominant cerebellar ataxia type 1 (ADCA I) and 11 with idiopathic late-onset cerebellar ataxia (ILOCA). The results were related to clinical and magnetic resonance imaging (MRI) findings. Cerebellar hypoperfusion was constant in ADCA I and frequent in patients with other spinocerebellar degenerations. Brain stem hypoperfusion was constant in ADCA I, frequent in ILOCA patients with pontocerebellar atrophy and absent in FA and EOCA. FA and EOCA often showed a reduction in the parietotemporal cortex blood flow, which was not related to cortical atrophy. ILOCA patients had an asymmetric pattern in the temporal areas with decreased blood flow in the right side only. Caudate hypoperfusion was found in ADCA I patients. Cerebral atrophy did not account for changes in regional blood flow, which probably indicate early involvement of cerebral structures.

Adult↗
PubMed1998

Dynamic imaging: scintimammography.

Although mammography remains the technique of choice for the early detection of breast cancer, new emerging breast imaging techniques such as ultrasound, magnetic resonance and radionuclide scanning have been investigated and included in many diagnostic protocols. This overview discusses the current problems related to radionuclide breast imaging trying to define its role in the management of women with suspicious breast lesions at mammography. A number of tumor-imaging agents have been recently used for the differential diagnosis of malignant and benign lesions in radiographically dense breasts and breasts with architectural distortions from prior biopsy or surgery or following radiation therapy. 99mTc-MIBI is the most used tracer which has become the paradigm of this new class of compounds suitable for breast imaging. The current sensitivity and specificity rates for breast scintigraphy with 99mTc-MIBI depend on a number of factors including lesion size and site. Sensitivity and specificity rates and positive and negative predictive values of 92, 89, 81 and 96%, respectively, have been reported in a large series of patients with palpable breast lesions, which figures have been confirmed in many other series. On the contrary, lower sensitivity has been reported for nonpalpable breast abnormalities or for lesions smaller than 1 cm. This observation, confirmed by many authors, implies that a new nonpalpable lesion that is suspicious for malignancy at mammography needs a histologic diagnosis. We also report the results of our recent studies on functional imaging with 99mTc-MIBI of the multidrug resistance phenotype in breast cancer patients. These studies followed an observation that this tracer is a suitable transport substrate for the P-glycoprotein (P-gp) which is commonly associated with the development of a multidrug resistance phenotype. We examined 30 patients with histologically confirmed breast carcinoma who had received no previous chemotherapy or preoperative local irradiation. We found a positive and significant correlation between the efflux rates of 99mTc-MIBI determined by in vivo kinetic analysis and the P-gp levels measured in vitro by quantitative autoradiography in the same tumors (r = 0.62; p < 0.001). More recently, we tested whether tumor clearance of 99mTc-MIBI can predict the response to neoadjuvant chemotherapy in patients with locally advanced breast cancer. Thirty-nine patients with stage III disease underwent 99mTc-MIBI scanning before neoadjuvant chemotherapy and the time to half-clearance of the tracer was calculated. The patients then received epirubicin and underwent mastectomy after completing chemotherapy. This study showed that a rapid tumor clearance of 99mTc-MIBI (< or = 204 min) can predict the lack of tumor response to neoadjuvant chemotherapy with drugs affected by multidrug resistance phenotype in advanced breast carcinoma patients. However, slower tracer clearance (> or = 204 min) did not guarantee an objective tumor response to chemotherapy in all patients, in agreement with the existence of several P-gp-independent mechanisms of drug resistance. We conclude that the preliminary study of this phenotype would allow to predict the response to (neo)adjuvant chemotherapy and select the appropriate treatment regimen for each patient. Finally, radionuclide breast scanning may be helpful in the differential diagnosis of malignant and benign breast lesions as a guide to subsequent chemotherapy.

Antineoplastic Agents↗
PubMed1998

Growth hormone deficiency in elderly patients with hypothalamo-pituitary tumors.

In 18 patients with hypothalamo-pituitary diseases aged over 60 years and in 18 sex, age- and BMI-matched healthy subjects, the results of plasma IGF-I and IGF-BP3 levels and the GH response to GHRH + arginine test (GHRH + ATT) were correlated to the results of body composition, serum osteocalcin (OC) and urinary cross-linked N-telopeptides of type I collagen (Ntx) and the bone mineral density (BMD). In 10 patients and 10 controls, the GH response to ITT was also evaluated. The GH response to GHRH + ATT and ITT was markedly reduced in patients compared to controls (3.1 +/- 0.7 vs. 23.2 +/- 2.3 micrograms/L, P < 0.001 and 1.1 +/- 0.3 vs. 6.4 +/- 0.8 micrograms/L, P < 0.001), so all patients were classified as GHD, though no significant difference was found in plasma IGF-I and IGF-BP3 levels between the two groups. Body composition analysis revealed a significant increase of fat mass (37.4 +/- 2.2 vs. 28.0 +/- 1.0%, P < 0.001), a significant decrease of lean mass (62.6 +/- 2.2 vs. 72.0 +/- 1.0%, P < 0.001) and total body water (45.7 +/- 1.5 vs. 52.5 +/- 1.1%, P < 0.001) in patients compared to controls. Serum OC levels were lower (1.9 +/- 0.1 vs. 4.6 +/- 0.4 micrograms/L, P < 0.001) in patients than in controls, whereas urinary Ntx levels were similar. BMD values in lumbar spine (0.81 +/- 0.02 vs. 0.90 +/- 0.02 g/cm2, P < 0.001) and femoral neck (0.70 +/- 0.02 vs. 0.82 +/- 0.02 g/cm2, P < 0.001) were significantly lower in patients than in controls. A significant inverse correlation was found between GHD duration and lumbar spine (r = -0.73, P&1t; 0.001) or femoral neck (r = -0.81, P&1t; 0.001) BMD values and a significant direct correlation was found between GH peak after GHRH + ATT and lumbar BMD (r = 0.69, p = 0.001) in GHD patients. In conclusion, GHD in patients over 60 yrs aged with a characteristic history of hypothalamus-pituitary pathology is distinct from the physiological decline in GH secretion associated with aging.

Aged↗
PubMed1998

Left ventricular function in young adults with childhood and adulthood onset growth hormone deficiency.

OBJECTIVE: The impairment of heart structure and function in adults with childhood onset GH deficiency has been recently described. However, previous echocardiographic studies have reported no differences in cardiac mass and function between adulthood onset GH deficient patients and healthy subjects. DESIGN: The aim of this study was to evaluate cardiac performance in adult patients with childhood and adulthood onset GH deficiency, using equilibrium radionuclide angiography, a method more accurate than echocardiography. PATIENTS: Eleven patients with childhood onset GH deficiency, 9 patients with adulthood onset GH deficiency and 12 age-, gender-, height- and weight-matched healthy subjects entered the study. MEASUREMENTS: All the study population underwent equilibrium radionuclide angiography at rest and during physical exercise. RESULTS: Both childhood and adulthood onset GH deficient patients had an impaired left ventricular systolic performance both at rest (ejection fraction was 55 +/- 6%, 55 +/- 10% and 66 +/- 6% in childhood and adulthood onset GH deficient patients and control group, respectively; P < 0.0001) and during physical exercise (ejection fraction was 54 +/- 9% in childhood onset GH deficient patients, 53 +/- 9% in adulthood onset GH deficient patients and 76 +/- 7% in normal subjects; P < 0.0001). Peak ejection rate was 3.2 +/- 0.8 end-diastolic volume/second, 3.0 +/- 0.6 end-diastolic volume/second and 3.9 +/- 0.8 end-diastolic volume/ second in childhood and adulthood onset GH deficient patients and control group, respectively (P < 0.01). Exercise-induced changes in end-systolic volume were increased in both groups of patients compared with healthy subjects. In contrast, exercise-induced end-diastolic volume changes were not different between GH deficient patients and controls. Resting peak filling rate was 2.6 +/- 0.7 end-diastolic volume/second, 2.5 +/- 0.7 end-diastolic volume/ second and 3.1 +/- 0.3 end-diastolic volume/second in the 2 groups of patients and healthy subjects, respectively (P < 0.05). Reduced exercise tolerance in all patients, as shown by the significantly lower values of peak workload (P < 0.0001), peak rate-pressure product (P < 0.01) and exercise duration (P < 0.0001) was observed. CONCLUSION: Patients affected by GH deficiency have left ventricular systolic dysfunction at rest and during physical exercise, suggesting that GH plays a physiological role in maintaining normal cardiac performance in humans. Furthermore, no difference between childhood and adulthood onset GH deficient patients was found indicating that both group of patients have an impairment of cardiac function.

Adult↗
PubMed1998

Effectiveness of chronic treatment with alendronate in the osteoporosis of Cushing's disease.

BACKGROUND: Osteoporosis is common in patients with Cushing's disease and is likely due to an imbalance between bone formation and resorption. Alendronate is an aminobisphosphonate that is able to increase bone mass mainly by inhibiting bone resorption. OBJECTIVE: We have evaluated the effect of chronic treatment with alendronate on bone mineral density (BMD) in patients with Cushing's disease. PATIENTS: 39 patients with Cushing's disease entered this study. 39 age-, sex- and BMI-matched normals served as controls for baseline evaluation. The 39 patients were divided into four groups: 1) 10 patients with active disease treated with alendronate and ketoconazole; 2) 11 patients with inactive disease treated with alendronate; 3) 8 patients with active disease treated with ketoconazole alone, 4) 10 patients with inactive disease received no treatment. TREATMENT PROTOCOL: Alendronate was given for 12 months in a dose of 10 mg orally once daily after fasting at 0800 h in the morning. Ketoconazole was given in a dose of 200-600 mg orally daily, when pituitary surgery was unsuccessful. STUDY DESIGN: Lumbar spine (L1-L4) and femoral neck BMD, serum osteocalcin (OC), urinary cross-linked N-telopeptides of type I collagen (Ntx) levels were evaluated at study entry, in patients and controls, and were repeated after 6 and 12 months in the 39 patients. RESULTS: BMD values were lower in patients with Cushing's disease than in controls at both L1-L4 (0.72 +/- 0.4 vs. 1.01 +/- 0.6 g/cm2, P < 0.05) and femoral neck (0.69 +/- 0.3 vs. 0.96 +/- 0.6 g/cm2, P < 0.05). In the 39 patients with Cushing's disease considered as a whole, serum OC levels were lower (1.1 +/- 0.1 vs 1.5 +/- 0.1 nmol/l, P < 0.01), while Ntx values were higher than in controls (168 +/- 25 vs. 61 +/- 31 nmol BCE/mmol creatinine, P < 0.01). In the alendronate-treated groups, serum OC levels increased, while Ntx levels significantly decreased after 6 and 12 months of treatment without any significant difference between the two groups. BMD values measured at L1-L4 and femoral neck significantly increased after 12 months of therapy. In patients of group 4, a significant increase of serum OC levels and a significant decrease of Ntx levels were observed together with a slight increase of BMD values after 12 months. No significant change in either biochemical markers or BMD values was found in patients of group 3. CONCLUSIONS: Patients with Cushing's disease have osteoporosis which needs to be rapidly reversed to limit the risk of fracture. The results of the present study show that a 12 month treatment period with alendronate induced an improvement in bone mineral density greater than in untreated patients.

Acute Disease↗
PubMed1998

Pattern of left ventricular filling in hypertrophic cardiomyopathy. Assessment by Doppler echocardiography and radionuclide angiography.

AIMS: The left ventricle in hypertrophic cardiomyopathy is anatomically and functionally non-uniform. This study was undertaken to verify whether a heterogeneity in the pattern of diastolic filling can be detected along the left ventricular inflow tract in hypertrophic cardiomyopathy. METHODS AND RESULTS: Early (E) and late (A) diastolic velocities were recorded by Doppler echocardiography at mitral and at mid-ventricular level in 16 normal volunteers and 30 patients with hypertrophic cardiomyopathy. Patients with hypertrophic cardiomyopathy also underwent radionuclide angiography to assess left ventricular function. E wave decreased significantly in normal volunteers (80 +/- 15 to 60 +/- 14 cm x s(-1); P<0.001), but it increased in hypertrophic cardiomyopathy (76 +/- 22 to 87 +/- 28 cm x s(-1) P=0.04), whereas the A wave decreased similarly in both. By multivariate analysis, systolic asynchrony and the ejection fraction of left ventricular lateral wall were directly related to the pattern of early filling progression (r=0.656, F=9.467; P<0.002). Moreover, systolic asynchrony showed a univariate direct correlation with changes in E velocity (r=0.42; P=0.02). CONCLUSION: Many patients with hypertrophic cardiomyopathy have an acceleration of filling within the left ventricular inflow tract; this phenomenon is directly related to systolic asynchrony and ejection fraction of the left ventricular lateral wall, suggesting increased suction.

Adolescent↗
PubMed1998

Tc-99m sestamibi imaging in the diagnostic assessment of patients with lymphomas: comparison with clinical and radiological evaluation.

Tc-99m MIBI imaging has been used in nuclear oncology, but its role in detecting lymphomas has not been widely investigated. In this study, 31 patients with lymphomas (20 non-Hodgkin's and 11 Hodgkin's) underwent Tc-99m MIBI whole-body imaging. A total of 74 tumor lesions were detected in 25 patients, while the remaining 6 patients were disease-free. The diagnostic accuracy of MIBI imaging for lesion detection was 85%. A total of 11 unknown tumor lesions in 3 patients were discovered on MIBI scans. Tumor size was significantly (p = 0.01) higher in lesions with increased MIBI uptake (3.5 +/- 2.0 cm) compared with those with no uptake (1.8 +/- 1.0 cm). No false positive MIBI findings were observed. The accuracy of MIBI scintigraphy in patients with Hodgkin's disease was lower (72%) compared to that of patients with non-Hodgkin's lymphomas (94%). However, this difference was not related to tumor type, but to lesion size. In fact, tumor size was significantly (p = 0.02) lower in lesions of patients with Hodgkin's disease (2.5 +/- 1.3 cm) compared to those of patients with non-Hodgkin's lymphomas (3.7 +/- 2.2 cm). MIBI imaging may be useful in patients with lymphomas for detecting tumor lesions and, hence, may be considered an alternative to gallium scanning, providing better imaging quality. However, the intense Sestamibi activity in the lower chest and abdomen as well as tumor size may limit the diagnostic sensitivity of this radionuclide technique in patients with lymphomas.

Abdominal Neoplasms↗
PubMed1998

Tumor clearance of technetium 99m-sestamibi as a predictor of response to neoadjuvant chemotherapy for locally advanced breast cancer.

PURPOSE: Since we have previously shown that the efflux rate of technetium 99m (99mTc) sestamibi, a transport substrate of P-glycoprotein (Pgp), is directly correlated with Pgp levels in untreated breast carcinoma, we tested whether tumor clearance of 9mTc-sestamibi may be predictive of therapeutic response to neoadjuvant chemotherapy in patients with locally advanced breast cancer. PATIENTS AND METHODS: Thirty-nine patients with stage III disease, median tumor diameter 5.8 cm (range, 3 to 10) were enrolled onto this prospective clinical trial and underwent 99mTc-sestamibi scan before neoadjuvant chemotherapy. Patients were injected intravenously (i.v.) with 740 MBq of 99mTc-sestamibi; a 15-minute dynamic study was performed, and static planar images were obtained at 0.5, 1, 2, and 4 hours. The time to half clearance of 99mTc-sestamibi was calculated in each patient from decay corrected time-activity curves using a monoexponential fitting. Patients were treated with epirubicin 150 mg/m2 i.v. every 2 weeks for three courses and then underwent surgery within 3 weeks from the completion of chemotherapy. Residual tumor was assessed by pathologic examination of mastectomy specimens. RESULTS: Seventeen of 39 patients showed a rapid tumor clearance of 9mTc-sestamibi (time to half clearance [t1/2] < or = 204 minutes) and 15 of these 17 (88%) showed a highly cellular macroscopic residual tumor at histology that indicated lack of tumor response to neoadjuvant chemotherapy. In contrast, only eight of 22 (36%) with prolonged retention of 99mTc-sestamibi (t1/2 > 204 minutes) showed residual macroscopic tumor at histology (Fisher's exact test, P < .01). CONCLUSION: A rapid tumor clearance of 99mTc-sestamibi may predict lack of tumor response to neoadjuvant chemotherapy with drugs affected by the multidrug-resistant phenotype in patients with locally advanced breast carcinoma.

Adult↗
PubMed1998

Correlation of scintigraphic results using 123I-methoxybenzamide with hormone levels and tumor size response to quinagolide in patients with pituitary adenomas.

The efficacy of dopaminergic agents in the medical treatment of pituitary adenomas is well known. Quinagolide is a nonergot derivative dopamine agonist, which binds dopamine D2 receptors with high affinity. The treatment with this drug is reported to suppress hormone levels and to cause tumor shrinkage in prolactinomas and in a few GH-secreting pituitary adenomas. In clinically nonfunctioning pituitary adenomas (NFPA), the efficacy of quinagolide treatment is controversial. The scintigraphy of the pituitary region using 123I-methoxybenzamide (123I-IBZM) allows us to visualize in vivo the expression of dopamine D2 receptors on pituitary tumors. In this study, the pituitary scintigraphy with 123I-IBZM was performed in 14 patients with macroadenoma before starting a long-term treatment with quinagolide: 6 NFPA with high circulating alpha-subunit levels, 4 PRL-secreting, and 4 GH-secreting adenomas. A 3-point score was used to grade the ligand accumulation within the pituitary adenomas: 0 = negative, 1 = moderate uptake (equal to that recorded in the cerebral cortex), and 2 = intense uptake (equal to that recorded in the basal nuclei). The treatment with quinagolide was carried out at the dose of 0.3-0.6 mg/day for 6-12 months. Clinical, biochemical and hormonal assessment was repeated monthly during the first 3 months, then quarterly. Sellar magnetic resonance imaging was performed before and after 6 and 12 months of quinagolide treatment, to evaluate tumor shrinkage (> 25% of baseline size). In all 14 patients, a significant positive correlation was found between the degree of 123I-IBZM uptake and the clinical response to quinagolide treatment (r = 0.90; P < 0.001). In particular, the normalization of serum alpha-subunit and PRL levels, respectively, was achieved in 3 patients with NFPA and in 2 patients with prolactinoma, who showed intense 123I-IBZM uptake in the pituitary region. In 4 of these 5 patients with positive scan, a significant tumor shrinkage occurred between 6 and 12 months after the beginning of quinagolide treatment. In all patients with GH-secreting adenoma, no significant uptake of 123I-IBZM was found and no significant decrease of circulating GH and/or insulin-like growth factor-I levels, and tumor shrinkage was obtained during long-term treatment with quinagolide. In conclusion, the pituitary scintigraphy with 123I-IBZM can be considered a useful tool to indicate adenomas with significant expression of functioning D2 receptors. This innovative technique may predict the response to long-term treatment with quinagolide in patients with NFPA, where the lack of pituitary hormone hypersecretion makes difficult the monitoring of medical treatment efficacy.

Adenoma↗
PubMed1998

Bone marker and bone density responses to dopamine agonist therapy in hyperprolactinemic males.

The aim of this prospective study was to evaluate the bone mineral density (BMD) at lumbar spine and femoral neck levels and biochemical parameters of bone turnover in 20 consecutive hyperprolactinemic males before and after an 18-month treatment with different dopamine agonists. Six patients received bromocriptine at a dose of 2.5-10 mg/day; 7 patients received quinagolide at a dose of 0.075-0.3 mg/day; 7 patients received cabergoline at a dose of 0.5-1.5 mg/week. BMD, serum PRL, testosterone, dihydrotestosterone, and osteocalcin (OC), and urinary cross-linked N-telopeptides of type I collagen (Ntx) levels were measured before and every 6 months during treatment. At study entry, BMD values were lower in patients than controls at both lumbar spine (0.82 +/- 0.03 vs. 1.18 +/- 0.01 g/cm2; P < 0.001) and femoral neck (0.85 +/- 0.02 vs. 0.92 +/- 0.02 g/cm2; P < 0.05) levels. Osteopenia or osteoporosis was diagnosed in 16 patients at the lumbar spine and in 6 of them at the femoral neck level. A significant inverse correlation was found between lumbar spine and femoral neck BMD values and both PRL levels and disease duration (P < 0.01). In the 20 patients, serum OC levels were significantly lower (2.1 +/- 0.1 vs. 9.3 +/- 2.4 microg/L; P < 0.01), whereas Ntx levels were significantly higher (157.8 +/- 1.1 vs. 96.4 +/- 7.4 nmol bone collagen equivalent/mmol creatinine; P < 0.001) than control values. A significant inverse correlation was found between serum PRL and OC (P < 0.01), but not Ntx, levels. After 18 months of treatment, serum PRL levels were suppressed, and gonadal function was restored in all 20 patients, as shown by the normalization of serum T (from 2.2 +/- 0.2 to 5.0 +/- 0.2 microg/L) and dihydrotestosterone (0.3 +/- 0.02 vs. 0.5 +/- 0.01 nmol/L) levels, without any significant difference among groups. A progressive significant increase in serum OC levels together with a significant decrease in Ntx levels were observed after 6, 12, and 18 months of treatment in the 3 groups of patients. A slight, although significant, increase in BMD values was recorded in all patients after 18 months of bromocriptine, quinagolide, and cabergoline treatment, serum OC levels were normalized after treatment, whereas neither urinary Ntx levels nor BMD values were normalized by 18 months of treatment with dopaminergic agents. In conclusion, treatment with bromocriptine, quinagolide, and cabergoline for 18 months, although successfull in suppressing serum PRL levels and restoring gonadal function, was unable to restore lumbar spine and femoral neck BMD and normalize Ntx levels. However, BMD was slightly increased during treatment, suggesting that additional bone loss was prevented after treatment of hyperprolactinemia.

Adult↗
PubMed1998

Impairment of bone status in patients with central diabetes insipidus.

The aim of the current study was to evaluate the biochemical parameters of bone metabolism and the bone mineral density (BMD) in patients with central diabetes insipidus, either treated or not treated with endonasal desmopressin. Eighteen patients with central diabetes insipidus and 18 sex- and age-matched healthy subjects entered the study. The patients were divided into 2 groups: patients who did not receive treatment with desmopressin for at least 1 yr (group 1), and patients chronically treated with desmopressin since the diagnosis of diabetes insipidus (group 2). Serum osteocalcin and urinary cross-linked N-telopeptide of type I collagen levels were measured in all patients and controls using RIA and enzyme-linked immunosorbent assay kits, respectively. BMD was measured at the lumbar spine (L1-L4) and at the femoral neck in all subjects, using a Hologic QDR 1000 analyzer (Hologic Inc., Waltham, MA). Serum osteocalcin concentrations were significantly lower, both in patients of group 1 and group 2, compared with healthy subjects (5.1 +/- 0.6 and 4.5 +/- 0.3 vs. 7.9 +/- 0.2 micrograms/L, P < 0.05), whereas urinary cross-linked N-telopeptide of type I collagen concentrations were similar in the three groups of subjects (72.8 +/- 2.2, 71.6 +/- 2.7, and 64.6 +/- 1.7 nmol bone collagen equivalent/mmol creatinine). BMD was significantly decreased in patients of groups 1 and 2, compared with controls, both at lumbar spine (0.84 +/- 0.06 and 0.87 +/- 0.04 vs. 1.01 +/- 0.02 g/cm2, P < 0.05) and femoral neck (0.78 +/- 0.06 and 0.80 +/- 0.04 vs. 0.93 +/- 0.02 g/cm2, P < 0.05). A significant inverse correlation was found between disease duration and BMD values, evaluated as T scores, both at lumbar spine (group 1: r = -0.952, P < 0.005; group 2: r = -0.921, P < 0.001) and at femoral neck (group 1: r = -0.914, P < 0.05; group 2: r = -0.683, P < 0.05). In conclusion, patients with central diabetes insipidus had a significant bone impairment, compared with healthy subjects. Replacement with endonasal desmopressin at standard doses was not able to prevent or reverse the bone impairment. These findings suggest that, in patients with central diabetes insipidus, bone status analysis is mandatory; and a bone-loss preventing treatment might be beneficial.

Administration, Intranasal↗
PubMed1998

In vivo detection of malignant thymic masses by indium-111-DTPA-D-Phe1-octreotide scintigraphy.

UNLABELLED: Many tumors with neuroendocrine characteristics express high amounts of somatostatin receptors that enable in vivo imaging with [(111)In-DTPA-D-Phe1]-octreotide. In this study, we have analyzed the feasibility in detecting and characterizing thymic masses by somatostatin receptor scintigraphy (SRS). METHODS: Eighteen patients (13 women, 5 men, ages 18-78 yr; mean +/- s.d. = 42.1 +/- 17.6 yr) were enrolled in this study. Eleven patients were studied during diagnosis and seven during routine follow-up. In seven patients, myasthenia gravis was the presenting symptom. SRS was performed within 4 wk after CT and/or MRI. Planar and tomographic images were acquired within 24 hr after the injection of approximately 111 MBq of [(111)In-DTPA-D-Phe1]-octreotide. The scintigraphic results were categorized according to the histologic findings. RESULTS: Histology diagnosed 10 mixed epithelial/lymphoid thymomas (8 with prevalent epithelial component), 2 thymic carcinomas, 1 thymic carcinoid, 1 lymphangioma and 4 thymic hyperplasias. Two thymoma were Stage I, 3 were Stage II, 2 were Stage III and 5 were Stage IV, as was the thymic carcinoid. Indium-111-DTPA-D-Phe1-octreotide concentrated in primary and/or metastatic sites of thymic tumors, thereby enabling successful external gamma imaging of sites greater than 1.5 cm in size. Tumor-to-lung (T/L) ratios were as high as 7.6-fold (range 1.7-7.6). Untreated thymomas showed higher T/L (4.34 +/- 1.57) than treated ones (2.68 +/- 1.18). No uptake was detectable in the four patients with benign thymic hyperplasia and the patient with the lymphangioma. CONCLUSION: Indium-111-DTPA-D-Phe1-octreotide is avidly concentrated within thymic tumors, but it is not concentrated by thymic hyperplasia, which allows differential diagnosis. Thus, in patients with myasthenia gravis, SRS may have a role in characterizing thymic masses, thereby overcoming the limits of cross-sectional imaging modalities.

Adolescent↗
PubMed1998

Technetium-99m-tetrofosmin uptake in brain tumors by SPECT: comparison with thallium-201 imaging.

UNLABELLED: Thallium-201 is clinically used for the assessment of primary and recurrent brain tumors. The biologic properties of 201Tl that allow it to accumulate within the tumor cells render 201Tl useful in evaluating tumor malignancy, but its physical characteristics and nonroutine availability limits its use in some institutions, as compared to 99mTc-labeled compounds. The aim of this study was to assess the feasibility of using 99mTc-tetrofosmin for imaging brain tumors and to compare its uptake with that of 201Tl. METHODS: Twenty-six patients with 27 intracranial masses were studied with SPECT. In the first group of seven patients (Group A), the timing for optimal acquisition of the 99mTc-tetrofosmin scan was assessed. In the second group of 19 patients (Group B), two sequential 201Tl (74-148 MBq intravenous) and 99mTc-tetrofosmin (740-925 MBq intravenous) studies were performed 20 min after tracer injection and compared. RESULTS: In Group A, no significant difference in the tumor-to-background (T/B) ratio among the 20-, 40- and 120-min postinjection studies was observed. In Group B, the quality of reconstructed images with 99mTc-tetrofosmin, judged visually, was superior to that of 201Tl in 47% of all studies and was comparable in the remaining 53%. A significant relationship between 201Tl and 99mTc-tetrofosmin T/B ratio (r = 0.75, p < 0.01) was found. The T/B ratio of 99mTc-tetrofosmin was significantly higher than that of 201Tl (23.3 +/- 21.5 compared to 6.1 +/- 2.9, p < 0.005). CONCLUSION: Technetium-99m-tetrofosmin is a suitable radiotracer for the imaging of intracranial lesions with SPECT. Moreover, a better definition of tumor margins and a higher contrast between neoplastic and normal brain tissue can be achieved.

Brain Neoplasms↗
PubMed1998

[Magnetic resonance in the study of suprarenal neoplasms. Qualitative and quantitative analysis of signal intensity].

INTRODUCTION: Magnetic Resonance Imaging (MRI) has been proposed as the diagnostic technique of choice to characterize adrenal tumors. However, the results of the current studies are controversial. MATERIAL AND METHODS: Forty-nine patients with unilateral adrenal masses were submitted to MRI for lesion characterization on the basis of MR signal intensity. Cytology and/or histology demonstrated 14 pheochromocytomas (pheos), 11 adenomas, 3 cysts, 2 myelolipomas, 4 carcinomas, 3 metastases and 1 fibrosarcoma; a clinical diagnosis of adenoma was made in the remaining 11 patients. MR studies were performed using spin-echo (SE) sequences with T1 (TR/TE = 600/17 ms) and T2 (TR/TE = 2000/15-90 ms) weighting. T1-weighted images were also acquired after Gadolinium-DTPA (Gd-DTPA) administration. MR studies were integrated with in- and out-of-phase (TR/TE = 100/4-6 ms) chemical-shift (CS) sequences. MR signal intensity (SI) was analyzed qualitatively and quantitatively; MR results were correlated with tumor type and hormone secretion. RESULTS: The qualitative analysis of T2 images showed high signal intensity in the majority (80%) of adrenal lesions (14 pheos, 12 adenomas, 3 cysts, 2 myelolipomas and 8 malignancies). The quantitative analysis of post-Gd-DTPA T1 images permitted to distinguish adenomas, cysts and myelolipomas from pheos and malignancies. The qualitative analysis of post-Gd-DTPA T2 and T1 images permitted to distinguish pheos and cysts from adenomas and malignancies (p < .05); however, pheos and cysts as well as adenomas and malignancies were not differentiated. MR SI was similar in secreting and nonsecreting adenomas from both a qualitative and a quantitative viewpoints. CS MRI permitted to distinguish adenomas (decreased signal intensity on out-phase relative to in-phase images) from other benign and malignant lesions (no signal change from out-phase to in-phase images). CONCLUSIONS: The qualitative analysis of MR SI on conventional T1 and T2 images does not permit to differentiate adrenal masses. The qualitative evaluation of T1 images after Gd-DTPA administration, the quantitative analysis and CS sequences are technical options improving lesion characterization.

Adrenal Gland Neoplasms↗
PubMed1998

Identification of viable myocardium in patients with chronic coronary artery disease using rest-redistribution thallium-201 tomography: optimal image analysis.

UNLABELLED: With the widely used 50% threshold, sensitivity is high, but specificity is low in detecting viable myocardium on 201Tl SPECT. In this study, we sought to identify the best threshold for semiquantitative 201Tl analysis. METHODS: Rest-redistribution 201Tl SPECT was performed in 46 patients with chronic coronary artery disease before and after myocardial revascularization. Regional function was evaluated by two-dimensional echocardiography before and after myocardial revascularization using a 3-point scale (1 = normal, 2 = hypokinetic, 3 = a/dyskinetic). Myocardial segments with abnormal systolic function were defined as viable if the systolic function score decreased > or = 1 after myocardial revascularization. A second group of 12 patients with chronic coronary artery disease constituted the validation population. Sensitivity-specificity curves, as well as receiver operating characteristic curves, for rest and redistribution mages were generated by varying the 201Tl uptake threshold. RESULTS: A 65% threshold uptake using resting images was found to be the best for detecting a/dyskinetic segments that improve after myocardial revascularization from those that do not improve. Sensitivity was lower with a 65% threshold (75%) than with a 50% threshold (90%, p < 0.05), but specificity was higher (76% versus 26%, p < 0.05) resulting in better accuracy (76% versus 57%, p < 0.05) and positive predictive value (77% versus 55%), while the negative predictive value was not different (69% versus 75%, p not significant). The area under the receiver operating characteristic curve was significantly (p < 005) larger for rest (0.80 +/- 0.05) as opposed to redistribution (0.72 +/- 0.05) images. Similar results were obtained in a subgroup of patients with low ejection fraction. Significant correlations between the percentage of revascularized viable segments and both the change in ejection fraction and in postrevascularization ejection fraction were found. When these findings were applied in the validation group, a gain in specificity, accuracy and positive predictive value was obtained with the 65% threshold compared with the 50% threshold. CONCLUSION: This study demonstrated that analysis of resting images and use of the 65% 201Tl uptake threshold is preferable for separating viable from not viable dyssynergic myocardial segments in patients with chronic coronary artery disease.

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