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Magnetic resonance imaging (MRI) is particularly well adapted to the evaluation of aortic distensibility. The calculation of this parameter, based on the change in vessel cross-sectional area per unit change in blood pressure, requires precise delineation of the aortic wall on a series of cine-MR images. Firstly, the study consisted in validating a new automatic method to assess aortic elasticity. Secondly, aortic distensibility was studied for the ascending and descending thoracic aortas in 26 healthy subjects. Two homogeneous groups were available to evaluate the influence of sex and age (with an age limit value of 35 years). The automatic postprocessing method proved to be robust and reliable enough to automatically determine aortic distensibility, even on artefacted images. In the 26 healthy volunteers, a marked decrease in distensibility appears with age, although this decrease is only significant for the ascending aorta (8.97+/-2.69 10(-3) mmHg(-1) vs. 5.97+/-2.02 10(-3) mmHg(-1)). Women have a higher aortic distensibility than men but only significantly at the level of the descending aorta (7.20+/-1.61 10(-3) mmHg(-1) vs. 5.05+/-2.40 10(-3) mmHg(-1)). Through our automatic contouring method, the aortic distensibility from routine cine-MRI has been studied on a healthy subject population providing reference values of aortic stiffness. The aortic distensibility calculation shows that age and sex are causes of aortic stiffness variations in healthy subjects., (Copyright 2010 Elsevier Inc. All rights reserved.)

Background: Congenital defects of the pericardium are rare and poorly known cardiac malformations. Most of them are left-sided and asymptomatic and are usually incidentally diagnosed., Aims: To describe the clinical, electrocardiographic, and imaging features of total absence of the left pericardium., Methods and Results: We report the cases of 3 patients who have been seen in our institution with a diagnosis of total congenital absence of the pericardium. All of them complained of precordial pain; one of them experienced disabling symptoms that justified surgical intervention. All of them had previously been suspected to have an atrial septal defect because of the echocardiographic appearance of right ventricular volume overload. Electrocardiogram, chest x-ray, echocardiography, and magnetic resonance imaging of the heart consistently showed remarkably similar features including leftward displacement, increased mobility, and interposition of lung tissue between the heart and other intrathoracic structures., Conclusion: Congenital absence of the left pericardium should be known by clinicians as a possible differential diagnosis of chest pain or pseudo-right heart overload., (Copyright 2010 Wiley Periodicals, Inc.)

Although previous studies have found that cerebral white matter hyperintensities are associated with balance-gait disorders, no proton magnetic resonance spectroscopy data at the plane of the basal ganglia have been published. We investigated a possible relationship between balance performance and brain metabolite ratios or structural MRI measurements. We also included neuropsychological tests to determine whether such tests are related to structural or metabolic findings. All 80 participants were taken from the cohort of the Three-City study (Dijon-Bordeaux-Montpellier, France). The ratios of N-acetyl-aspartate to creatine (NAA/Cr) and choline to creatine (Cho/Cr) were calculated in the basal ganglia, thalami and insular cortex. We used univariate regression to identify which variables predicted changes in NAA/Cr and Cho/Cr, and completed the analysis with a multiple linear or logistic regression. After the multivariate analysis including hypertension, age, balance-gait, sex, white matter lesions, brain atrophy and body mass index, only balance-gait performance remained statistically significant for NAA/Cr (p=0.01) and for deep white-matter lesions (p=0.02). The Trail-Making Test is independently associated with brain atrophy and periventricular white-matter hyperintensities. Neuronal and axonal integrity at the plane of the basal ganglia is associated with balance and gait in the elderly, whereas brain flexibility is associated with structural MRI brain abnormalities.

Our objective was to investigate the influence of hypertension on N-acetylaspartate (NAA) and choline (Cho) ratios in brain tissues in a community-dwelling elderly population. Brain flexibility was also evaluated with regard to the same metabolite ratios. Proton magnetic resonance spectroscopy (MRS) and the Trail Making Test (TMT) were performed in 80 subjects (75.7+/-4 years old) from the Three-City Study. Fifty-eight participants had hypertension. The NAA/creatine (Cr) and Cho/Cr ratios were obtained in the insular cortex, the thalami and the deep periventricular white matter. In addition, the B-A score of the TMT was evaluated. Uni- and multi-variate analyses were performed in order to examine the relationships among these data. In the insula and the thalami of the hypertensive group, NAA/Cr ratios were significantly lower (1.39+/-0.23 and 1.52+/-0.23, respectively; p=0.01) than those in the normotensive control group (1.52+/-0.25 and 1.70+/-0.19, respectively; p<0.0001), whereas no such reduction was observed in the periventricular white matter of older hypertensive brains. Moreover, the NAA or Cho ratios were significantly correlated with the TMT B-A scores at the level of the thalami, insula and periventricular white matter. These statistical results were confirmed by the multivariate analysis. In an elderly population, hypertension leads to a reduction in NAA/Cr ratios in the insula and the thalami, possibly due to a decrease in blood flow through small perforating and cortical arteries. The TMT B-A test appears to be relevant not only for the frontal areas but also for more remote areas such as the thalami, the insula and the deep periventricular white matter.

Aims: to investigate the association between admission hyperglycemia and myocardial damage in patients with ST-segment elevation myocardial infarction (STEMI) using Cardiac Magnetic Resonance (CMR)., Methods: We analyzed 113 patients with STEMI treated with successful primary percutaneous coronary intervention. Admission hyperglycemia was defined as a glucose level >/= 7.8 mmol/l. Contrast-enhanced CMR was performed between 3 and 7 days after reperfusion to evaluate left ventricular function and perfusion data after injection of gadolinium-DTPA. First-pass images (FP), providing assessment of microvascular obstruction and Late Gadolinium Enhanced images (DE), reflecting the extent of infarction, were investigated and the extent of transmural tissue damage was determined by visual scores., Results: Patients with a supramedian FP and DE scores more frequently had left anterior descending culprit artery (p = 0.02 and <0.001), multivessel disease (p = 0.02 for both) and hyperglycemia (p < 0.001). Moreover, they were characterized by higher levels of HbA1c (p = 0.01 and 0.04), peak plasma Creatine Kinase (p < 0.001), left ventricular end-systolic volume (p = 0.005 and <0.001), and lower left ventricular ejection fraction (p = 0.001 and <0.001). In a multivariate model, admission hyperglycemia remains independently associated with increased FP and DE scores., Conclusion: Our results show the existence of a strong relationship between glucose metabolism impairment and myocardial damage in patients with STEMI. Further studies are needed to show if aggressive glucose control improves myocardial perfusion, which could be assessed using CMR.

This paper presents a tumor detecting system that allows interactive 3D tumor visualization and tumor volume measurements. An improved level set method is proposed to automatically segment the tumor images slice by slice. PET images are used to detect the tumor while CT images make a 3D representation of the patient's body possible. An initial slice with a seed within the tumor is firstly chosen by the operator. The system then performs automatically the tumor volume segmentation that allows the clinician to visualize the tumor, to measure it and to evaluate the best medical treatment adapted to the patient.

Purpose: To evaluate, in breast cancer patients treated by neoadjuvant chemotherapy, the predictive value of reduction in FDG uptake with regard to complete pathological response (pCR)., Methods: Forty-seven women with non-metastatic, non-inflammatory, large or locally advanced breast cancer were included. Tumour uptake of FDG was evaluated before and after the first course of neoadjuvant chemotherapy. Four indices were used: maximal and average SUV without or with correction by body surface area and glycaemia (SUV(max), SUV(avg), SUV(max-BSA-G) and SUV(avg-BSA-G), respectively). The predictive value of reduction in FDG uptake with respect to pCR was studied by logistic regression analysis. Relationships between baseline [(18)F]FDG uptake and prognostic parameters were assessed., Results: The relative decrease in FDG uptake (DeltaSUV) after the first course of neoadjuvant chemotherapy was significantly greater in the pCR group than in the non-pCR group (p < 0.000066). The four FDG uptake indices were all strongly correlated with each other. A decrease in SUV(max-BSA-G) of 85.4% +/- 21.9% was found in pCR patients, versus 22.6% +/- 36.6% in non-pCR patients. DeltaSUV(max-BSA-G) <-60% predicted the pCR with an accuracy of 87% and DeltaSUVs were found to be only factors predictive of the pCR at multivariate analysis. An elevated baseline SUV was associated with high mitotic activity (p < 0.0016), tumour grading (p < 0.004), high nuclear pleomorphism score (p < 0.03) and negative hormonal receptor status (p < 0.005)., Conclusion: In breast cancer patients, after only one course of neoadjuvant chemotherapy the reduction in FDG uptake is an early and powerful predictor of pCR.

Objectives: To evaluate phase-sensitive reconstructed images versus magnitude images generated by an inversion recovery pulse sequence for the determination of myocardial infarct size in delayed-enhancement cardiac magnetic resonance (DE-CMR) at 3 T., Materials and Methods: Thirty patients were examined at 3 T and DE images were obtained 10 minutes after contrast agent administration using a phase-sensitive breath-hold segmented inversion recovery gradient echo sequence. From magnitude and phase images, the percentage of hyperenhanced myocardium was expressed. Contrast-to-noise ratio (CNR) measurements were performed in hyperenhanced and normal myocardium., Results: We observed excellent correlation and concordance between hyperenhanced myocardium determined on phase-sensitive reconstructed and magnitude images. The mean CNR values were significantly higher in phase-sensitive reconstructed images compared with magnitude images (10.5 +/- 5.4 vs. 6.1 +/- 4.8; P < 0.001)., Conclusions: DE-CMR with phase-sensitive reconstruction at 3.0 T provides similar results to magnitude images, but with a significantly greater CNR between infarcted and normal myocardium.

Purpose: To retrospectively evaluate magnetic resonance (MR) imaging, hydrogen 1 (1H) MR spectroscopy, apparent diffusion coefficient (ADC), T1, and T2 measurements for prediction of late neurologic outcome in term neonates after severe perinatal asphyxia., Materials and Methods: This study was approved by the local ethics committee. Informed consent from parents was not required. Thirty term neonates (12 boys, 18 girls; age range, 2-12 days) with severe hypoxic-ischemic encephalopathy were examined during the first 12 days of life with conventional and diffusion-weighted cerebral MR imaging, 1H MR spectroscopy with absolute quantification, and T1 and T2 measurements. Quantitative 1H MR spectroscopy, T1, and T2 data were acquired on one 10-mm slab positioned at the level of the basal ganglia. The neonates were assigned to one of two groups according to their late (>12-month follow-up) neurologic outcome: those with an unfavorable outcome-that is, death or severe disability-and those with a favorable outcome. Clinical data, MR signal intensity abnormalities, ADCs, 1H MR spectroscopy findings, and relaxation times were compared by using Chi2 testing and analysis of variance to individualize the prognostic indicators., Results: The unfavorable (n=16) and favorable (n=14) outcome groups were similar in terms of clinical data (ie, Apgar scores, visceral hypoxic injuries), visualization of brain edema on MR images, and T1 and T2 relaxation times. Late unfavorable neurologic outcome was associated with a mixed pattern of cortical and basal ganglia signal intensity abnormalities on MR images (13 babies with unfavorable vs three babies with favorable outcomes, P=.001) and with decreased absolute N-acetylaspartate (NAA) and choline concentrations in all brain structures, especially the basal ganglia (mean NAA concentration: 2.72 mmol/L in unfavorable outcome group vs 4.66 mmol/L in favorable outcome group, P<5x10(-9)), as measured with MR spectroscopy. In the basal ganglia, an NAA concentration lower than 4 mmol/L indicated an unfavorable individual prognosis with 94% sensitivity and 93% specificity. Significantly reduced ADCs also were noted in the unfavorable outcome group, but only during the first 6 days of life., Conclusion: Conventional MR imaging findings, spectroscopically measured absolute NAA and choline concentrations, and ADCs are complementary tools for predicting the individual outcomes of severely asphyxiated term neonates.

We have recently described two kindreds presenting thoracic aortic aneurysm and/or aortic dissection (TAAD) and patent ductus arteriosus (PDA) and mapped the disease locus to 16p12.2-p13.13 (ref. 3). We now demonstrate that the disease is caused by mutations in the MYH11 gene affecting the C-terminal coiled-coil region of the smooth muscle myosin heavy chain, a specific contractile protein of smooth muscle cells (SMC). All individuals bearing the heterozygous mutations, even if asymptomatic, showed marked aortic stiffness. Examination of pathological aortas showed large areas of medial degeneration with very low SMC content. Abnormal immunological recognition of SM-MHC and the colocalization of wild-type and mutant rod proteins in SMC, in conjunction with differences in their coimmunoprecipitation capacities, strongly suggest a dominant-negative effect. Human MYH11 gene mutations provide the first example of a direct change in a specific SMC protein leading to an inherited arterial disease.

The aim of this work is to evaluate the relationship between improvement of regional myocardial function and visual analysis of contrast-enhanced (CE) MRI in patients after acute myocardial infarction. MRI was performed on 19 patients 1 and 11 weeks after a reperfused acute myocardial infarction. Perfusion data (first-pass images [FPI] and delayed CE images) were acquired after an intravenous bolus of gadolinium-DTPA and visually analyzed using a 17 segment model. Each segment was then classified in 3 groups, according to the presence or absence of FPI and CE patterns at baseline study: group 0: normal-appearing segments; group 1: segments with delayed hyper-enhancement but no early hypo-enhancement; group 2: segments with early hypoenhancement. Relative Wall thickening (RWT) was analyzed in each segment and its improvement evaluated in each group. Between first MRI and follow-up study, a significant improvement of RWT occurred in group 1 (mean +/- SD) [from 43.43 +/- 26.59% to 76.71 +/- 47.38%; p = 0.001] but not in group 2 (from 32.73 +/- 25.58% to 39.57 +/- 30.57%; p = NS). In group 0, RWT despite normal value at baseline study exhibited a significant improvement at follow-up (from 65.23 +/- 46.52% to 79.73 +/- 48.46%; p = 0.0015). In conclusion, the combined analysis of early and delayed perfusion abnormalities in MRI in the week following myocardial infarction can predict myocardial viability and allows in the future an evaluation of the efficacy of perfusion therapy.

Background: The long-term outcome of repaired aortic coarctation may be complicated by dilatation of the ascending aorta notably in patients with bicuspid aortic valve. Magnetic resonance imaging was used to compare the size of the ascending aorta in patients with bicuspid or tricuspid aortic valve., Methods: In 50 patients with a repair of aortic coarctation, the size of the ascending aorta was measured in a bicuspid aortic valve group (n=11) and a tricuspid aortic valve group (n=39). The aortic diameter was measured at the level of the sinus of Valsalva and at the widest part of the ascending aorta using magnetic resonance imaging., Results: The mean age of patients at surgical repair was respectively 2.2+/-3.3 years for the bicuspid aortic valve group and 2.5+/-3.5 years for the tricuspid aortic valve group (p=NS) and the mean age at the time of the magnetic resonance imaging was 10.2+/-4.7 years and 9.3+/-5.9 years (p=NS) respectively. A significant difference in the aortic diameter was found between the bicuspid aortic valve group and the tricuspid aortic group both at the level of sinus of Valsalva (34.8+/-8.2 mm, 19.5+/-4.4 mm, respectively, p<0.01) and at the level of the ascending aorta (36.8+/-7.2 mm, 16.9+/-3.4 mm, respectively, p<0.01)., Conclusions: The occurrence of ascending aortic dilatation is significantly associated with the presence of a bicuspid aortic valve. This requires long-term follow-up, which can be effectively performed by magnetic resonance imaging.

Objectives: We sought to investigate the diagnostic ability of cardiac magnetic resonance imaging (MRI) perfusion in acute reperfused myocardial infarction. The study used fuzzy logic to automatically classify signal intensity-time curves from myocardial segments into 3 categories: normal, hypointense, and Hyperintense., Materials and Methods: Thirty-eight patients with myocardial infarction underwent short-axis cine-MRI and contrast-enhanced MRI to provide data on wall thickening and the transmural extent of infarction. Of these, 17 had a second cardiac MRI to ascertain the functional recovery in each segment., Results: The fuzzy logic based classification performs well (kappa= 0.87, P < 0.01) in comparison with a visual approach. Segments providing "hypo" curves do not recover (Delta = 0.11 SD = 0.96) whereas segments demonstrating the other curve types recover (Delta = 1 SD = 1.98 for "hyper" curves and Delta = 1.54 SD = 1.77 for "normal" curves)., Conclusions: The proposed automatic signal intensity-time curve classification has a prognostic value when studying the functional recovery of pathologic segments and clearly identifies the no-reflow phenomenon known to induce poor recovery.

Background: Three loci have been shown to be responsible for nonsyndromic familial thoracic aortic aneurysms (TAAs) and aortic dissections (ADs). We recently described a large family in which TAA/AD associates with patent ductus arteriosus (PDA) and provided genetic arguments for a unique pathophysiological entity., Methods and Results: Genome-wide scan was performed in 40 subjects belonging to 3 generations in this large pedigree. Using the 7 TAA/AD cases as affected, we observed positive 2-point LOD scores on adjacent markers at chromosome 16p, with a maximum LOD score value of 2.73 at theta=0, a value that increased to 3.56 when 5 PDA cases were included. Multipoint linkage analysis yielded a maximum LOD score of 4.14 in the vicinity of marker D16S3103. Fine mapping allowed the observation of recombinant haplotypes that delimited a critical 20-cM interval at 16p12.2-p13.13. Automatic determination of aortic compliance with cine MRI showed that all subjects bearing the disease haplotype, even asymptomatic, displayed a very low level of aortic compliance and distensibility. Aortic stiffness was strongly associated with disease haplotype with a marked effect of age, indicating subclinical and early manifestation of the disease., Conclusions: Genetic analysis of this family identified a unique locus responsible for both TAA/AD and PDA at chromosome 16p12.2-p13.13 with aortic stiffness as an early hallmark of the disease. TAA/AD with PDA is a new monogenic entity among the genetically heterogeneous group of TAA/AD disease.

MRI with paramagnetic contrast agent allows the assessment of the extent of myocardial tissue injury after infarction. Visual segmental scoring has been widely used to define the transmural extent of myocardial infarction, but no attempt has been made to use visual scores in order to assess the percentage of the whole myocardium infarcted. By summing all the segmental scores using a 17-segment model, a global index of the size of the infarcted myocardium is easily obtained. The entire left ventricle of 60 patients with a recent myocardial infarction was scanned using an ECG-gated gradient echo sequence after injection of gadolinium contrast agent. The global score was defined as the sum of the scores on each segment, and expressed as a percentage of the maximum possible score. This index was compared with a planimetric evaluation of hyperenhancement, expressed as a percentage of the left ventricle myocardial volume. There is a good correlation between the two methods (r=0.91; y=1.06x+0.20), and the Bland-Altman plot shows a high concordance between the two approaches (mean of the differences =1.45%). A visual approach based on a 17-segment model can be used to evaluate the global myocardial extent of the hyperenhancement with similar results to planimetry.

Magnetic resonance first-pass imaging of a bolus of contrast agent is well adapted to distinguish normal and hypoperfused areas of the myocardium. In most cases, the signal intensity-time curves in user defined regions of interest (ROI) are studied. As image acquisition is ECG-gated, the images are acquired at the same moment in the cardiac cycle, and the basic shape of the heart is similar from one view to the next. However, superficial respiratory motion can displace the heart in the short-axis plane. The aim of this study is to correct for the respiratory motion of the heart by performing an automatic realignment of the myocardial ROI based on a method tracking the movement of the lung-myocardium interface. Visual and quantitative analyses performed on 120 curves show a very good concordance between two automatic methods and the manual one.

Objective: To evaluate the accuracy of thallium-201 (201TI) scintigraphy in distinguishing a benign from a malignant recent non-traumatic vertebral fracture., Methods: STUDY DESIGN--Single center, prospective study. PARTICIPANTS--Patients hospitalized for a recent non-traumatic vertebral fracture. EVALUATION--Usual clinical, laboratory and radiological assessment; 201TI vertebral scintigraphy: patients were injected with iv 3 mCi 201TI. Early and delayed images of the fractured vertebra were obtained. DATA ANALYSIS--(1) Two examinators, unaware of the other findings, rated the images as hyperfixation or not of the fractured vertebra; (2) the ratio (average count per pixel of the fractured vertebra/normal adjacent vertebrae) were calculated. The FINAL DIAGNOSIS was established on the result of vertebral biopsy or on follow-up., Results: Twenty-one patients were included. The final diagnosis was a benign vertebral fracture in 14 patients and a malignant vertebral fracture in 7. The sensitivity, specificity, positive and negative predictive values for a malignant fracture on early 201TI vertebral scintigraphy images were 28.6, 92.9, 66.6, and 72.2%, respectively, and on delayed images were 28.6, 100, 100, and 73.7%, respectively. The ratio of lesioned over normal tissue was not increased in malignant, compared with benign fractures., Conclusion: The weak sensitivity does not support the wide use of 201TI bone scintigraphy to distinguish a benign from a malignant recent non traumatic vertebral fracture. However, the high specificity suggests that such evaluation might be proposed prior to vertebral biopsy in some difficult cases.

The main goal of urgent imaging evaluation of patients with suspected CNS infection is to differentiate infectious from tumoral or vascular lesions in order to provide appropriate management. MR imaging, including diffusion weighted imaging and spectroscopy, is superior to CT imaging to characterize lesion location and etiology. The CT and MRI features of the more frequent bacterial, viral and parasitic CNS infections will be described.

To study the role of nitric oxide (NO) in lung metastasis of breast carcinoma, we isolated two cell clones (H and J) from the parental EMT-6 murine breast carcinoma cell line, based on their differential NO production. In vitro, EMT-6 J cells, but not EMT-6H cells, constitutively expressed inducible NO synthase (NOS II) and secreted high levels of NO. IL-1beta increased NO production in both clones, and TNF-alpha had a synergistic effect on IL-1beta-induced NO production, but NO production by EMT-6 J cells was always higher than by EMT-6H cells. Proliferation, survival and adhesion to lung-derived endothelial cells of both clones were similar and were not affected by NO. In vivo, both clones similarly located in the lungs of syngeneic mice 48 h after injection. However, EMT-6H cells were significantly more tumorigenic than EMT-6 J cells as assessed at later time points. Injection of EMT-6 J cells and simultaneous treatment of mice with aminoguanidine (AG), a NOS II inhibitor, significantly increased tumour formation. Injection of EMT-6H and EMT-6 J cells into NOS II-deficient mice resulted in a significant survival increase as compared with wild-type animals. Simultaneous administration of AG increased the death rate of NOS II-deficient mice injected with EMT-6 J cells. These results demonstrate that: (i) NO does not influence the early stages of tumour metastasis to the lungs and (ii) NOS II expression in tumour cells reduces, while NOS II expression in host cells enhances, tumour nodule development. In conclusion, the cellular origin and the local NO production are critical in the metastatic process.

Aims: To evaluate the relationship between N-terminal Pro-Brain Natriuretic Peptide (N-BNP) level and contrast-enhanced MRI in patients after acute myocardial infarction (MI)., Methods: Eighty-two patients were studied. Venous blood samples were obtained 3 days after MI and MRI was performed from 2 to 7 days after MI, with determination of left ventricular function and acquisition of perfusion data after injection of gadolinium-DTPA. First-pass images (FPI) and Delayed contrast-enhanced (CE) images were analyzed using a 17-segment model, and the extent of transmurality was determined by a visual score., Results: Univariate analysis showed that age (P<0.001), sex (P<0.02), Left Ventricular Ejection Fraction (LVEF) <45% (P<0.002), creatinine (P<0.05) and delayed CE-MR images (P<0.006) were predictors of a supramedian N-BNP level. FPI was not a predictor in this univariate analysis (P<0.078). In a multivariate model, only age, LVEF <45% and delayed CE-MRI were associated with an increased N-BNP level., Conclusion: After MI, high N-BNP levels are dependent on the LVEF but also on the myocardial infarct size derived from the delayed CE-MR images.

Unlabelled: The aim of our study was to evaluate and compare in thyroid cancer patients the predictive value for disease progression of thyroglobulin (Tg) levels measured under thyroid-stimulating hormone (TSH) stimulation, in the postoperative period just before (131)I ablative therapy and at the time of control 6-12 mo later., Methods: Two-hundred twelve consecutive patients treated for a well-differentiated thyroid carcinoma (184 papillary, 28 follicular) with no initial distant metastases were retrospectively studied. All patients had a total or near-total thyroidectomy followed by ablation with 3.7 GBq (131)I. Tg levels were determined just before ablative therapy (Tg1) and 6-12 mo later (Tg2). Thresholds of 30 and 10 ng/mL were used for Tg1 and Tg2, respectively. Univariate and multivariate analyses were performed to assess the predictive value for disease progression of the 2 Tg determinations., Results: Thirty patients had a Tg1 level > 30 ng/mL. Six to 12 mo later, 30 patients had a Tg2 level > 10 ng/mL, 19 of whom had initially a Tg1 level > 30 ng/mL. Disease progression was reported in 20 patients (9%). Progression-free survival rates were significantly lower in patients with a low Tg1 or Tg2 level but the difference was more important with Tg2. With univariate analysis, 5 variables were significantly associated with disease progression: Tg2, Tg1, node invasion, extrathyroidal extension, and tumor size. With multivariate analysis, only Tg2 (odds ratio [OR] = 16.4; 95% confidence interval [95% CI] = 5.7-47.4; P < 0.001) and node invasion (OR = 2.7; 95% CI = 1.0-7.2; P = 0.04) had an independent prognostic value. When only initial parameters were considered, Tg1 and node invasion were the 2 independent prognostic factors. The OR decreased for Tg1 (OR = 10.1; 95% CI = 4.0-25.7; P < 0.001) but increased for node invasion (OR = 4.4; 95% CI = 1.7-11.2; P = 0.002)., Conclusion: Among all clinical and tumoral variables, lymph node invasion and serum Tg level are 2 important parameters to define the risk of disease progression. Although Tg2 appears more significant than Tg1, both Tg levels measured under TSH stimulation, in the postoperative period and a few months after ablative therapy, have a predictive value. In clinical practice, patients at risk can be selected as soon as the initial lymph node status and Tg1 level are known.

Background and Purpose: Proton spectroscopy and quantitative diffusion-weighted imaging (DWI) were used to investigate the pertinence of N-acetyl aspartate (NAA) as a reliable marker of neuronal density in human stroke., Methods: The time courses of tissue water apparent diffusion coefficient (ADC(w)) and metabolite T2 were investigated on a plane corresponding to the largest area of cerebral infarction, within and outside the site of infarction in 71 patients with a large cortical middle cerebral artery territory infarction., Results: Significant reductions are seen in NAA T2 deep within the infarction during the period comprised between 5 and 20 days postinfarction; the relaxation times appearing to normalise several months after stroke. After an acute reduction in ADC(w), the pseudonormalisation of ADC(w) occurs at 8-12 days after the ischaemic insult. The minimum in N-acetyl aspartate T2 relaxation times and the pseudonormalisation of ADC(w) appear to coincide., Conclusions: The data suggest that modifications in the behaviour of the observed proton metabolites occur during the period when the vasogenic oedema is formed and cell membrane integrity is lost. For this reason, NAA may not be a reliable marker of neuronal density during this period.

Thoracic aortic aneurysm and aortic dissection (TAA and AD) are an important cause of sudden death. Familial cases could account for 20% of all cases. A genetic heterogeneity with two identified genes (FBN1 and COL3A1) and three loci (3p24-25 or MFS2/TAAD2, 5q13-q14 and 11q23.2-24) has been shown previously. Study of a single family composed of 179 members with an abnormally high occurrence of TAA/AD disease. A total of 40 subjects from three generations were investigated. In addition to five cases of stroke and three cases of sudden death, there were four cases of AD and four cases of TAA in adults. In all, 11 cases of patent ductus arteriosus (PDA) were observed, two of which were associated with TAA and one with AD. Segregation analysis showed that the distribution of these vascular abnormalities was more likely compatible with a single genetic defect with an autosomal dominant pattern of inheritance. There were no clinical signs of Marfan, Elhers-Danlos vascular type or Char syndromes. Genetic linkage analysis was performed for seven genes or loci implicated in familial TAA/AD disease (COL3A1, FBN1, 3p24-25 or MFS2/TAAD2, 5q13-q14 and 11q23.2-q24), Char syndrome (TFAP2B) or autosomal recessive PDA (12q24). Using different genetic models, linkage with these seven loci was excluded. Familial TAA/AD with PDA is likely to be a particular heritable vascular disorder, with an as yet undiscovered Mendelian genetic basis.

The calculation of the left ventricular ejection fraction (LVEF) is dependent upon the accurate measurement of diastolic and systolic left ventricular volumes. Although breath-hold cine magnetic resonance imaging (MRI) allows coverage of the whole cardiac cycle with an excellent time resolution, many authors rely on the visual selection of diastolic and the systolic short-axis slices in order to reduce the postprocessing time. An automatic method was developed to detect the endocardial contour on each image, allowing an automatic selection of the systolic frame. The calculated ejection fraction was compared with radionuclide ventriculography (RNV). Sixty-five patients were examined using an electrocardiogram (ECG)-gated gradient echo sequence. Among these examinations, manual and automatic processing with MRI were compared when the time of the systolic frame concorded. Good correlations have been found between the automatic MRI approach and RNV, and between manual and automatic processing on MRI alone. The results show that the automatic determination of the ejection fraction is feasible, and should constitute an important step toward a larger acceptance of MRI as a routine tool in heart disease imaging. One major benefit of using automatic postprocessing is that it may eliminate the visual choice of the systolic frame, inaccurate in more than 50% of the studied patients.

Objective: This study was designed to assess the prognostic value of myocardial tomoscintigraphy perfusion imaging after percutaneous coronary intervention (PCI) in asymptomatic diabetic patients., Methods: One hundred and fourteen diabetic patients were followed up during 27+/-16 (mean+/-SD) months after the myocardial tomoscintigraphy. PCI-related events were studied after myocardial tomoscintigraphy stress testing and included major cardiac events (MACE) (cardiovascular death, myocardial infarction) and revascularization (bypass surgery or new PCI). Stress myocardial tomoscintigraphy imaging was performed 5+/-5 months after PCI and ischemia was considered as present if at least 2 contiguous segments were showing reversible defects., Results: Persistent silent ischemia was found in 49/114 (43%) patients. No difference was observed between the two groups for MACE: four among the 65 (6%) non ischemic patients versus 2 among the 49 (4%) ischemic patients (NS). In contrast, 15 (31%) among the ischemic patients and 4 (6%) among the non ischemic patients underwent iterative revascularization (p<0.01). The relative risk of revascularization for patients with significant ischemia was 5.5 versus non ischemic patients (p<0.001)., Conclusion: After PCI, in asymptomatic diabetic patients followed by myocardial tomoscintigraphy a high frequency of persistent silent ischemia was found and associated with a high risk for repeat interventional procedure, although no increase in major cardiac events was observed.

Purpose: A better understanding of the significance of diffuse hyperdensity affecting the circle of Willis and the dural sinuses on unenhanced CT., Materials and Methods: We performed a retrospective study of 19 patients with a neurological manifestation and a CT scan without contrast injection. Among these 19 patients, six had been included because of primary or secondary polycythemia. The analysis of cerebral CT scans was made qualitatively by visual inspection and quantitatively., Results: In patients with a hematocrit percentage exceeding 60%, both circle of Willis and dural sinuses were dense on unenhanced CT scans. A linear relation between the hemoglobin level and the contrast of the dural sinuses compared with the grey matter was observed with an excellent correlation (r = 0.934; n < 0.0001; p = 19)., Conclusion: Increased density of cerebral vessels on unenhanced CT is a sign of a high hemoglobin level.

Magnetic resonance imaging allows an accurate calculation of the left ventricular ejection fraction and left ventricular volumes. Additionally, it makes possible to assess myocardial perfusion after gadolinium chelate injection. Late after the injection, the presence of a myocardial hyper-enhancement can be visualized. The present study has used the 17 segment standardized nomenclature for tomographic imaging of the heart as recommended for all cardiac imaging modalities. Sixty nine patients were studied after a revascularised myocardial infarction. All patients had Timi grade 3 flow in the infarct-related artery after therapy. Regional and global function was studied using cine MR short axis slices. The gadolinium chelate first pass was scored using a 5 level scale reflecting the transmural extent of the segmental myocardial enhancement. The delayed enhancement due to gadolinium accumulation in the myocardium 10 min post injection was scored in the same manner. Left ventricular ejection fraction was 51 +/- 13%. Segmental thickening parameters (systolic thickness, absolute thickening and relative thickening) appeared statistically related to the hypoperfusion and delayed enhancement scores. Absolute myocardial thickening varied from 4.8 +/- 2.7 mm in the myocardial segments free of any delayed enhancement to 2.4 +/- 2.1 mm in segments presenting with a transmural extent of the delayed hyper-enhancement. Scores obtained after gadolinium injection were also well correlated with the global left ventricular function (r = 0.65, p < 0.01 for late enhancement). Magnetic resonance imaging of the heart allows a precise characterisation of revascularised myocardium which makes this technique very attractive for evaluating the treatments designed to improve myocardial microperfusion.

The aim of this work is to study the regional myocardial perfusion by MRI early after revascularised myocardial infarction and to compare it with regional function. This prospective work has included 15 patients with acute first myocardial infarction that was precociously revascularised. A myocardial MRI was performed between D2 and D10 after myocardial infarction. The regional myocardial thickening was evaluated from cine-MRI sequences. For the study of myocardial perfusion, the first pass of the contrast agent was analysed from curves of the signal evolution versus time. The signal enhancement on late images acquired 10 minutes after the perfusion of the contrast agent was also evaluated. Among 384 studied myocardial segments, those with a normal gadolinium first pass curve had a relative thickening of 46 +/- 38%. The segments with a severely reduced first pass kinetic have a markedly reduced relative thickening (14 +/- 20%) in relation with myocardial hypoperfusion. The myocardial enhancement is frequently seen in the infarct territory and appears related to a reduced regional contractility. The myocardium is enhanced on late images in 12% of the normally perfused segments. These segments have a mildly reduced wall thickening (3.36 +/- 2.84 mm vs 4.42 +/- 2.83 mm). The segmental contractility in a reperfused myocardial infarction appears to depend both on the myocardial perfusion which reflects the microvascularisation and on the myocardial enhancement which is linked to myocardial structural alterations. MRI appears to be an adequate method to evaluate these abnormalities and allows an easy assessment of the no-reflow phenomenon, if present.

Many of the previous studies of vascular dementia using proton magnetic resonance (MR) spectroscopy had been carried out on white matter. However, no proton spectroscopic data of the subcortical gray matter are available in such disease. We report two cases suffering from vascular dementia, with an unilateral N-acetylaspartate (NAA) decrease on subcortical gray matter. This significant reduction in NAA ratios was associated with an increase of choline on the ipsilateral centrum semiovale. We discuss the pathophysiology of these cases.

Rationale and Objectives: Aortic compliance is defined as the relative change in aortic cross-sectional area divided by the change in arterial pressure. Magnetic resonance imaging (MRI) is a useful imaging modality for the noninvasive evaluation of aortic compliance. However, manual tracing of the aortic contour is subject to important interobserver variations. To estimate the aortic compliance from cine-MRI, a method based on fuzzy logic theory was elaborated., Materials and Methods: Seven healthy volunteers and eight patients with Marfan syndrome were examined using an ECG gated cine-MRI sequence. The aorta was imaged in the transverse plane at the level of the pulmonary trunk. A method based on fuzzy logic was developed to automatically detect the aortic contour., Results: Through our robust automatic contouring method, the calculation of aortic cross-sectional areas allows an estimation of the aortic compliance., Conclusion: The aortic compliance can be obtained from a fuzzy logic based automatic contouring method, thereby avoiding the important interobserver variation often associated with manual tracing.

Cerebral tissue with T2 magnetic resonance imaging (MRI) abnormalities following stroke is generally considered infarcted, while surrounding regions with normal MRI appearance are believed to be healthy. To assess whether these surrounding regions consist of normal tissue, we explored the distribution of N-acetylaspartate (NAA) and lactate within and around the hyperintense area on T2-weighted MRI using proton MR spectroscopy. The study was carried out in 25 patients with middle cerebral artery occlusion imaged between 1 and 42 days after stroke onset. NAA/choline (Cho) ratios were significantly reduced in both areas of T2 hyperintensity and in surrounding tissue. The reduction was greater in the region of T2 hyperintensity than in the surrounding region (-50% vs. -28%, respectively) and was unrelated to the delay after the ictus. Lactate/Cho ratios increased massively within the abnormal T2 area, but did not differ from control values beyond the margin of hyperintensity. Overall data indicate that T2 visible lesions on MRI do not infer the entire injured tissue.

Background: The prognostic value of (201)Tl myocardial imaging has been demonstrated in several studies concerning patients with a known significant coronary artery disease. However, the evolution of a coronary stenosis after stenting is difficult to predict. This study was designed to assess the prognostic value of (201)Tl single-photon emission computed tomography (thallium SPECT) perfusion imaging in patients after intracoronary stenting., Methods: One hundred fifty-two patients were studied. They were followed up during 40 +/- 13 (mean +/- SD) months after thallium SPECT. Stent-related events were studied after thallium stress testing and included cardiovascular death, myocardial infarction, and revascularization. Stress thallium imaging was performed 5 +/- 2 months after stenting, and ischemia was considered to be present if at least 2 contiguous segments were showing reversible defects., Results: Only 3 (3%) among the 105 nonischemic patients had major cardiac events during the follow-up versus 13 (28%) of the 47 ischemic patients (P < .001) after thallium SPECT. The relative risk of major cardiac events for patients with significant ischemia was 10.5 compared with nonischemic patients (P < .001). Fourteen (30%) of the ischemic patients and 8 (8%) among the nonischemic patients underwent iterative revascularization (P < .001). Therefore, only 11 (10%) of the nonischemic patients had major cardiac events or revascularization compared with 24 (51%) of the ischemic patients (P < .001)., Conclusions: Absence of ischemia on thallium SPECT imaging at 5 months after coronary stenting indicates a low risk for cardiovascular events or interventional procedure. These results may have important clinical implications in patient treatment.

The authors studied the risk factors for dilatation of the ascending aorta in patients operated for coarctation of the aorta. A prospective study of the diameters of the ascending aorta by magnetic resonance imaging was undertaken in 46 patients with an average age of 30 months (range 6 days to 11 years) at surgery, and 10 years of age (6 months to 31 years) at the time of the investigation. The diameters were measured at the level of the sinus of Valsalva, at the sino-tubular junction, and compared with reference tables with respect to body surface area. Twenty six per cent of patients had dilatation of the ascending aorta. The predisposing factors were investigated. Age, type of surgery, postoperative hypertension. Doppler gradient in the isthmic region, anatomical appearances of the repair observed by MRI were not predictive of this complication. On the other hand, age of patients at MRI and bicuspid aortic valves (present in 66% of cases) (p < 0.05) were significant risk factors. These results indicate that regular follow-up by echocardiography or MRI of the diameter of the ascending aorta is necessary in patients operated for coarctation of the aorta and with bicuspid aortic valves.

The objective of this study was to assess the reliability of the diagnosis of mesial temporal lobe epilepsy using EEG and sphenoidal electrodes. Inter-ictal 99 m Tc-HMPAO SPECT scans were registered in 21 patients with confirmed mesial temporal lobe epilepsy identified by scalp EEG and sphenoidal electrodes. Visual and quantitative SPECT analysis was performed blind to EEG data. An asymmetry index (AI) was measured from the ratio of two symmetrical regions of interest. A temporal lobe hypoperfusion was defined as an uptake reduced by 5% with respect to the contralateral region. Inter-ictal SPECT abnormalities were observed in 12 out of 21 patients (57%) from both visual and quantitative analysis (focal hypoperfusion in 11 cases, focal hyperperfusion in one case). In seven patients (33%) both visual and quantitative scintigraphy were normal. Abnormal AI was found in 11/15 patients with a high frequency of seizures and in 1/6 patients with a low frequency of seizures. The major data is that the probability to have an abnormal SPECT is statistically correlated to the frequency of the epileptic fits. The couple EEG recordings with sphenoidal electrodes and SPECT is sensitive and reliable in the diagnosis of mesial temporal lobe epilepsy.

Background and Purpose: To evaluate the functional prognostic value of proton magnetic resonance spectroscopy performed within the 5 days of an infarction of the middle cerebral artery territory, compared with previously demonstrated prognostic factors., Methods: Proton magnetic resonance spectroscopy was performed on 77 consecutive non-comatosed patients during the acute stage of middle cerebral artery infarction. The functional status was determined for each patient via the Orgogozo score. Proton magnetic resonance spectroscopic data were acquired in the infarction and in contra-lateral normal tissue and the results were expressed as metabolite ratios. Correlations were evaluated between the Orgogozo score at day 1 and day 30, the age, the sex, the volume of the infarction, and the metabolic ratios., Results: In a monovariate analysis, the decrease of the NAA/choline ratio was correlated with a low Orgogozo score at days 1 and 30 (P<0.05) and with a large infarction (P<0.05). A stepwise analysis showed a significant relationship between the Orgogozo score at day 30 and the Orgogozo score at day 1, the sex, the volume of infarction, and the NAA/Cho ratio within the infarction., Conclusions: Our work demonstrates that a good clinical outcome at day 30 depends on a good initial clinical score at day 1, a small volume of infarction, a small decrease of NAA/Cho, and being of the female gender.

Background: The most common effect of postmyocardial infarction (post MI) rehabilitation is an increase of peak maximal oxygen consumption correlated with changes in calf muscle metabolism, but there are few data on follow-up after rehabilitation on skeletal muscle and maximal oxygen consumption. The purpose of this study was to investigate the respective modifications in skeletal muscle metabolism and peak oxygen consumption (VO2) occurring during a supervised rehabilitation program and 1 year after MI in patients free of heart failure., Methods: Fifteen outpatients were studied prospectively after the acute phase of the MI, at the end of the rehabilitation program (2 months after the MI), and 1 year after. The rehabilitation comprised 20 sessions with three sessions per week. The program consisted of exercise training with bicycle, arm ergometer, and treadmill. The program also included respiratory exercises, psychological support, and counseling for secondary prevention of cardiovascular diseases. At each visit, a stress test on a bicycle ergometer was performed and the peak VO2 was measured. Phosphorus magnetic resonance spectroscopy of the gastrocnemius muscle was performed at rest and during a plantar flexion-type exercise against an adjustable load. Data were analyzed using analysis of variance and post-hoc test when appropriate., Results: The mechanical power output measured during the bicycle exercise increased from 111 +/- 28 watts at the post MI test to 136 +/- 40 watts after rehabilitation (post rehab) and decreased to 125 +/- 36 watts at 1 year. The peak VO2 increased significantly (P < 0.05) from 22 +/- 7 ml/kg-1/min-1 (post MI) to 27 +/- 9 ml/kg-1/min-1 (post rehab), and decreased significantly to 24 +/- 8 ml/kg-1/min-1 (1 year). The mechanical power output measured in the magnet during the stress test increased from 2.22 +/- 0.13 watts (post MI) to 2.85 +/- 1.24 (post rehab), and stabilized at 2.78 +/- 1.10 watts at 1 year. At the highest workload attained in the three successive tests, the phosphocreatine/(phosphocreatine + inorganic phosphate) ratio rose significantly (P < 0.05) from 0.46 +/- 0.13 (post MI) to 0.51 +/- 0.13 (post rehab) and remained at 0.51 +/- 0.13 at 1 year., Conclusion: The improvement of the peak VO2 after training post MI is not maintained 1 year later. This decline is not accompanied by muscular metabolic abnormalities. This suggests that the muscle metabolism after MI remains normal, and that the long-term decrease of the peak VO2 reflects a global deconditioning that should be avoided by maintaining a long-term phase III rehabilitation program.

The term non-invasive and non-echographic myocardial imaging is used to describe the advances in nuclear cardiology and magnetic resonance imaging underlying the most recent developments in investigating the myocardium. The value of new techniques such as rapid CT scan and cardiological applications of the synchroton are described. The main clinical applications of these techniques in the present and future are reviewed, especially with regards to ischaemic heart disease.

Purpose: To determine the extent to which the number of planes imaged at magnetic resonance (MR) imaging could be reduced without modifying the calculated volume and thickness of the left ventricle., Materials and Methods: Sixty-one patients were examined after a myocardial infarction. The whole left ventricle was imaged by using 5-mm contiguous breath-hold cine MR short-axis sections with no gap (SAng) (two-dimensional fast low-angle shot sequence, 9/4.8 [repetition time msec/echo time msec]). The effect of omitting one section in two (short-axis sections with 5-mm gap [SA5 mm]) or two sections in three (short-axis sections with 10-mm gap [SA10 mm]) was studied., Results: In the comparison of SA5 mm or SA10 mm with respect to the reference SAng, the standard error of the estimate (SEE) for the diastolic volume did not exceed the 6.1% interobserver SEE, and the SEE for the ejection fraction remained lower than the 3% interobserver SEE. The measured wall thickness was not affected. In addition, six simple geometric models were compared with SAng and yielded an SEE of 9.5%-28.1% for the diastolic volume and 3.8%-13.3% for the ejection fraction., Conclusion: In the study of left ventricles with heterogeneous contractility, short-axis imaging is more accurate than geometric modeling and permits wall thickness measurements when an intersection gap of 5 or 10 mm is used.

We investigated the time course of genesis of skeletal muscle dysfunction and sympatho-vagal imbalance after myocardial infarction. We studied 22 normal controls, 22 patients with >6 months stable chronic heart failure and 10 patients after a first massive myocardial infarction at 1-3 weeks (the "early" period), 6-8 weeks ("mid") and 6-9 months ("late") following their infarct. Four patients developed overt heart failure. Forearm muscle metabolism was studied using (31)P magnetic resonance spectroscopy (MRS). Sympatho-vagal balance was assessed by heart rate variability and radiolabelled norepinephrine kinetics. Increased norepinephrine spillover (0.55+/-0.02 v 0.27+/-0.04 mg/min/m(2); P<0.01) and decreased heart rate variability were confined to those post-myocardial infarction patients who subsequently developed heart failure. Resting cardiac output was normal in all the post-myocardial infarction patients, although the response of cardiac output to supine bicycle exercise at the "mid" study point was less in the group who subsequently developed heart failure (9+/-1 v 41+/-8 %; P<0.005). In the MRS studies, there were no detectable differences between those who did or did not develop heart failure. The initial rate of ATP turnover, calculated from initial-exercise changes in pH and phosphocreatine (PCr), was increased in established chronic heart failure, but in the post-myocardial infarction patients a numerically similar increase reached statistical significance only in the early group (19+/-3 v 11+/-1 mM/min; P<0.005). The apparent maximum rate of oxidative ATP synthesis, calculated from post-exercise PCr recovery kinetics, was lower than control in the late post-myocardial infarction and established chronic heart failure groups 34+/-5 v 55+/-4 mM/min; P<0.03 and 38+/-3 v 55+/-4 mM/min; P<0.003, respectively). Skeletal muscle metabolism and autonomic function become abnormal after an extensive myocardial infarction. While skeletal muscle abnormalities are relatively slow to develop and unrelated to the degree of failure, excessive neurohormonal activation and impaired cardiac output response to exercise seem from an early stage to characterize patients who subsequently develop chronic heart failure., (Copyright 1999 Academic Press.)

Metabolic changes induced by cerebral infarction or by stenosis and occlusion of the internal carotid artery have been previously described in 1H Magnetic Resonance Spectroscopy (1H MRS). These changes are essentially characterized by decreased N-acetyl-aspartate (NAA) and increased lactate concentration. Little is known about the metabolic changes observed in the three days following a transient ischemic attack (TIA), in the absence of stenosis or occlusion of the internal carotid artery, and without visible infarction on Magnetic Resonance Imaging (MRI). We studied five patients with a TIA lasting between 30 min and 3 h, affecting the sensory and motor functions of the brachio-facial territory with or without aphasia. A Computerized Tomography Scan (CT-scan), an electro-encephalogram, cervical Doppler ultrasound and MRI with proton magnetic resonance spectroscopy were performed on the affected cerebral area and on the normal contralateral homologous cerebral area within three days of the onset of TIA. None of the five patients had stenosis or occlusion of the internal carotid artery on Doppler ultrasound, or cerebral infarction on MRI. From 1H MRS ratio measurements, we did not observe any significant changes in the NAA/Creatine ratio. However, a rise in Lactate/Creatine ratio was observed in the symptomatic non-infarcted area compared with the normal cerebral tissue. During the first three days following a transient ischemic attack, there is an increase in lactate production. This change may reflect transient local hypoperfusion which could be long enough to stimulate lactate production, but short enough not to induce infarction. This region could be at risk from infarction in the long term.

The introduction of fuzzy logic improves a system for the automatic quantification of renal artery lesions seen in digital subtraction angiograms. A two-step approach has been followed. An earlier system based on non-fuzzy syntactic analysis provided a clear symbolic description of the stenotic lesions. Although this system worked correctly, it did not take into account the variability and uncertainty inherent to image processing and to knowledge on the reference diameter. This system has been improved by the introduction of fuzzy logic in the representation of the reference diameter. It provides a description of the stenosis in terms of fuzzy quantities. To illustrate the benefits of the fuzzy approach, the results of the two systems have been compared by plotting the differences of an index of variability. It appears that the differences are statistically different when using a two-tailed paired t-test (t = 2.37; p = 0.025). The result shows that the fuzzy approach is better than a non-fuzzy approach in the sense that the index of variability is reduced significantly.

Rationale and Objectives: Gated cardiac cine magnetic resonance imaging provides accurate dynamic data of the left ventricular function. However, the manual extraction of important physiologic parameters such as myocardium wall thickness and left ventricular volumes is invariably time consuming and subjective. To reduce the variability and time constraints inherent in observer contour tracing, the authors developed an automatic left ventricle contour-detection method., Methods: The purpose was to apply fuzzy logic-based automatic contour detection to identification of endocardial and epicardial borders in short-axis magnetic resonance images. The automatic contouring was compared with manual tracing using the calculated ejection fraction as the comparison criterion., Results: A good correlation was found between the two approaches (r2 = 0.98)., Conclusions: The ejection fraction can be obtained using this automatic contouring method.

Objective: To evaluate muscle bioenergetics, muscle cross-sectional area (CSA), and soreness when the gastrocnemius was subjected to concentric and concentric/eccentric resistance training modes., Design: Prospective study, before and after training. The subjects served as their own controls., Setting: Rehabilitation center and nuclear magnetic resonance spectroscopy unit of a university hospital., Participants: Sixteen healthy young volunteers from the local physiotherapist school., Intervention: Two distinct resistive training programs were evaluated on the gastrocnemius: a protocol consisting of concentric contractions only and a mixed concentric/eccentric program., Main Outcome Measures: Maximal isometric resistance was measured after each training session. Before and after training, muscle CSA was appreciated using magnetic resonance imaging, whereas changes in muscle pH, phosphorus metabolite ratios, maximal oxidative power (Pmax), and oxidative phosphorylation were studied using 31P nuclear magnetic resonance spectroscopy at rest and during an incremental exercise protocol., Results: Magnetic resonance imaging revealed a significant increase (7.1%) in the gastrocnemius CSA in the concentric-eccentric group only. The PCr/Pi (8.3 +/- 0.9 vs 10.4 +/- 1.7) and PCr/ATP (3.68 +/- .36 vs 4.07 +/- .27) resting ratios increased significantly (p = .008) after concentric-eccentric resistance training. Pmax was significantly improved in the concentric-eccentric group (7.0 +/- 2.1W vs 8.4 +/- 1.8W: p < .02). This mixed protocol also reduced the incidence of muscular soreness., Conclusion: The data suggest that the improved oxidative mechanical power output could be due mainly to a greater muscle cross-section in the concentric-eccentric group, with circumstantial evidence suggesting a relatively higher type IIa fiber activity.

Background: Total body 131-iodine labeled scintiscan is used to screen for residual tumoral tissue after ablation of differentiated thyroid carcinoma. At therapeutic doses, radioactive iodine can also be used for treatment. Thyroglobulin level, usually undetectable a few months after total thyroidectomy and metabolic irradiation with 131-iodine in patients without initial metastases, is absolutely necessary for interpreting the scintiscans. Iodine uptake occur in dermoid cysts which usually contain thyroid tissue., Case Report: A 44-year old woman underwent total thyroidectomy with node dissection for papillary carcinoma of the thyroid with a vesicular architecture. Four months later, the total body 131-iodine scintiscan demonstrated a round zone of uptake in the pelvic area. The lesion was found to be a typical dermoid cyst. No thyroid or tumoral tissue could be demonstrated., Discussion: Dermoid cysts can be the cause of false positive 131-scintiscans in patients followed after resection of differentiated thyroid carcinoma. Unlike previously reported cases, the dermoid cyst in this patient was totally devoid of thyroid tissue.

Background: Previous studies have demonstrated that epirubicin (EPI) has a lower propensity to produce cardiotoxic effects than doxorubicin (DXR) at high doses., Hypothesis: The aim of the study was to compare the cardiotoxicity induced by low doses of EPI and DXR in patients before and 1 month after the end of chemotherapy., Method: In a prospective study, 99 patients with a mean age of 51 +/- 12 years and without cardiac disease were studied before and 1 month after the end of chemotherapy. Group 1 included 38 patients receiving 246 +/- 96 mg/m2 of DXR and Group 2 included 61 patients receiving EPI with and equivalent dose of 219 +/- 92 mg/m2 of DXR. Ejection fraction (EF) of the left ventricle (LV), peak ejection rate (PER), and peak filling rate (PFR) [expressed in end-diastolic volume/s (EDV/s)] were evaluated by gated radionuclide angiography; PFR/PER were also calculated., Results: Moderate and similar alterations of left ventricular ejection fraction were shown for low doses of anthracyclines. The EF of the LV decreased from 57 +/- 6% to 54 +/- 6% for DXR group (Group 1) (p = 0.005), and from 58 +/- 5% to 55 +/- 5% for the EPI group (Group 2)(p = 0.001). The PER of the left ventricle fell from 3.08 +/- 0.46 EDV/s to 2.79 +/- 0.49 in Group 1 (p = 0.004) and from 2.98 +/- 0.50 to 2.73 +/- 0.34 EDV/s in Group 2 (p = 0.001). In contrast, no significant alteration of PFR appeared in Group 2 (from 2.72 +/- 0.51 to 2.62 +/- 0.41 EDV/s) for the equivalent dose of anthracycline, while PFR of the LV dropped from 2.82 +/- 0.76 (EDV/s) to 2.41 +/- 0.55 after doxorubicin (p = 0.004). No difference was found between 1 and 12 months after the end of the treatment in 25 patients in Group 1 and 28 patients in Group 2. These results confirm the advantage of EPI over DXR in terms of cardiotoxicity and help explain the relationship of cellular damage mechanisms with the functional parameters of nuclear investigation., Conclusion: A possible explanation for specific alteration after DXR could be the increased production of semiquinone free radicals, which are known to induce membrane damage and, consequently, myocardial edema and diastolic alteration.

Purpose: The aim of this preliminary study was to evaluate the effects of low-frequency electrical stimulation of quadriceps and calf muscles on global exercise capacities, skeletal muscle metabolism, calf muscle volume, and cardiac output in patients with chronic heart failure., Methods: Fourteen patients with chronic heart failure (mean age of 56.4 years +/- 9.1 SD; mean radionuclide left ventricular ejection fraction of 22.3% +/- 8.8 SD) underwent 5 weeks (1 hour per day, 5 days per week) of low-frequency electrical stimulation of quadriceps and calf muscles., Results: Low-frequency electrical stimulation was well tolerated. Exercise capacity and the calf muscles volumes increased significantly after rehabilitation in comparison with prior rehabilitation (the peak oxygen consumption increased from 17.2 mL/(kgmin) +/- 5.3 SD to 19.6 mL/(kgmin) +/- 5.9 SD; the anaerobic threshold increased from 12.3 mL/(kgmin) +/- 3.2 SD to 15.2 mL/(kgmin) +/- 3.3 SD; the 6-minute walking test increased from 419 m +/- 122 SD to 459 m +/- 114.3 SD; the gastrocnemius volume increased from 259.4 cm3 +/- 58 SD to 273.4 cm3 +/- 74 SD, and the soleus volume increased from 319 cm3 +/- 42.9 SD to 338 cm3 +/- 52.5 SD). The New York Heart Association class was improved after rehabilitation. The P-31 nuclear magnetic resonance spectroscopy of gastrocnemius muscle data were not significantly modified after rehabilitation, thereby inferring that no significant improvement of the muscle metabolism occurred. These data reinforce the hypothesis of an increased muscle mass during stimulation. It is noteworthy that the electrical stimulation did not increase cardiac output at any stage; an enormous asset in favor of this mode of rehabilitation., Conclusion: These results suggest that low-frequency muscular electrical stimulation is well tolerated, induces an increased exercise capacity in patients with chronic heart failure, without an undesirable increase in cardiac output.

Objective: To determine by 31P nuclear magnetic resonance (NMR) spectroscopy the efficacy of training in improving aerobic metabolism of calf muscle in nonamputated limb after recent vascular amputation; to assess the possible associated microcirculatory changes; and to evaluate the need for noninvasive monitoring techniques during training in the nonamputated limb after recent vascular amputation., Design: Prospective study, before and after training. Subjects served as their own controls and were compared with a control group., Setting: Rehabilitation center of a university hospital., Patients: Ten unilateral vascular amputated patients were included with ankle systolic index between 0.5 and 0.8 in the nonamputated limb, and 10 control subjects without cardiovascular disease or risk factors of atherosclerosis with ankle systolic index of >.95., Intervention: Walking with prosthesis at self-selected velocity over increasing walking distance, arm training at a workload of 60% of a maximal arm test, and analytical exercises of the nonamputated leg (dynamic contractions against low resistance). Subjects received training as inpatients, 5 days a week., Main Outcome Measures: Before and after training, ankle systolic index, forefoot transcutaneous oxygen tension (TcPO2) and veno-arteriolar reflex, and digital plethysmography of the second toe with reactive hyperemia test were studied. Changes in calf muscle pH, phosphocreatine (PCr), and inorganic phosphate (Pi) were measured by 31P NMR spectroscopy at rest and during a plantar flexion-type incremental protocol., Results: There was no significant difference in ankle systolic index (.63 +/- .10 vs .64 + .07) or in TcPO2 (42 +/- 11 vs 44 +/- 10mmHg), and there was reappearance of veno-arteriolar reflex in 3 cases, of a plethysmographic signal in 2 cases, and of the positivity of the reactive hyperemia test in 3 cases. No differences were found with 31P NMR spectroscopy at rest before and after training. At the same workload (1 watt) the difference of the ratio (PCr/(PCr + Pi)) of rest to effort (PCr depletion) was significantly increased in the amputated patients (.423 +/- .159 vs .145 +/- .058; p < .01). This difference of ratio was lower after training (.360 +/- .158 vs .423 +/- .159; p < .05). The pH was less acid between the two periods., Conclusion: Vascular monitoring with systolic index and TcPO2 is necessary to follow and to prevent serious ischemia of the nonamputated limb. Claudication is often not detected because of early exhaustion during walking. Training after recent vascular amputation improves the skeletal muscle oxidative capacity.