Objective: This study aims to determine how magnetic resonance imaging (MRI) acquisition techniques and calculation methods affect T2 values of knee cartilage at 1.5 tesla and to identify sequences that can be used for high-resolution T2 mapping in short scanning times. Materials and Methods: This study was performed on phantom and 29 patients who underwent MRI of the knee joint at 1.5 tesla. The protocol includes T2 mapping sequences based on Single-Echo Spin Echo (SESE), Multi-Echo Spin Echo (MESE), Fast Spin Echo (FSE) and Turbo Gradient Spin Echo (TGSE). The T2 relaxation times were quantified and evaluated using three calculation methods (MapIt, Syngo Offline and mono-exponential fit). signal-to-noise ratios (SNR) were measured in all sequences. All statistical analyses were performed using the t-test. Results: The average T2 values in phantom were 41.7 ± 13.8 ms for SESE, 43.2 ± 14.4 ms for MESE, 42.4 ± 14.1 ms for FSE and 44 ± 14.5 ms for TGSE. In the patient study, the mean differences were 6.5 ± 8.2 ms, 7.8 ± 7.6 ms and 8.4 ± 14.2 ms for MESE, FSE and TGSE compared to SESE, respectively; these statistical results were not significantly different (p > 0.05). The comparison between the three calculation methods showed no significant difference (p > 0.05). The t-test showed no significant difference between SNR values for all sequences. Conclusion: T2 values depend not only on the sequence type but also on the calculation method. None of the sequences revealed significant differences compared to the SESE reference sequence. TGSE with its short scanning time can be used for high-resolution T2 mapping.
We have conducted a prospective randomized controlled trial to evaluate the role of low-dose unfractionated heparin prophylaxis in preventing central venous line-related thrombosis in patients with haemato-oncological disease. Patients were randomly assigned to receive either prophylactic intravenous unfractionated heparin (continuous infusion of 100 IU/kg/daily) or 50 ml/daily of normal saline solution as a continuous infusion. CVLs were externalized, non tunneled, double lumen catheters. All CVLs were placed percutaneously by the same physician in the subclavian vein. Upper limb veins were systematically examined by ultrasonography just before, or <24 hours after, catheter removal, and in case of clinical signs of thrombosis. One hundred and twenty-eight CVLs were inserted. Catheter-related thrombosis occurred in 1.5% of the catheters inserted in patients of the heparin group, and in 12.6% in the control group (p = 0.03). No other risk factors were found for the development of catheter-related thrombosis. Two and three patients experienced severe bleeding in the heparin group, and in the control group, respectively (p = 0.18). There were no other side-effects clearly ascribable to the use of unfractionated heparin. This is the first prospective, randomized study, which shows that low-dose of unfractionated heparin is safe and effective to prevent catheter-related thrombosis in patients with haemato-oncological disease.
Objective: The purpose of this study was to compare T1 and T2 relaxation times of normal and pathologic Achilles Tendon (AT) in order to evaluate the ability of these methods to detect early Achilles tendon tendinosis. Materials and Methods: Forty-eight subjects were included in this study. Twenty-two subjects were classified as normal group and twenty-six subjects as patient group with tendinosis. MR examination was performed by 3 Tesla scanner using a 12 channel head coil. For relaxation times quantification, we used a sagittal 3D FLASH variable flip angle gradient echo UTE sequence (3D VFA-GE UTE) for T1 mapping and a sagittal Multi Echo Spin Echo sequence (MESE) for T2 mapping. Relaxation times were quantified using two different algorithms written in MATLAB. P value < 0.05 was considered statistically significant. Results: Our results showed a statistically significant difference in T1 and T2 values for the normal group compared to the patient group (p<0.05). Mean values of T1 and T2 were 571.69 ms and 24.16 ms for the normal group and 818.10 ms and 32.43 ms for the patient group, respectively. Results reported no correlation (r=0.193) for T1 mapping and a positive significant moderate correlation (r=0.542, p=0.000) for T2 mapping between the normal and patient groups. T1 and T2 showed no correlation in the normal group (r= 0.091, p=0.489) and a positive significant weak correlation in the patient group (r=0.263, p=0.048). Conclusion: We concluded that T1 and T2 relaxation times are relatively sensitive to diagnosis degenerative changes in the AT and T1 is more sensitive to AT tendinosis compared to T2.
BackgroundRheumatoid arthritis (RA) is a chronic autoimmune disease characterized by the presence of rheumatoid factor (RF) and anti-cyclic citrullined peptide (ACPA). ACPA have higher specificity than RF for RA, and are associated with joint radiographic damage and extra-articular manifestations.ObjectivesThe aim of this study was to evaluate the US RA activity whether the ACPA were present or not.MethodsA cross-sectional study of patients followed-up for RA was conducted. Demographic, clinical and biological data were collected. RF and ACPA mesures were collected from medical records. We calculated the US-DAS28 in order to evaluate accurate activity of RA. All patients had an ultrasound (US) examination of 22 joints of hands (wrists, metacarpophalangeal, proximal interphalangeal). US was performed by an operator blinded to clinical and laboratory data. RA activity was evaluated by US-DAS28 by replacing swollen joints of the hands by joints expressing synovial hypertrophy or hyper vascularization in US.ResultsOne hundred and eighteen patients were enrolled, 83% were females. The mean age was 53 years-old. The mean duration of the disease was 11.6 months. The RF was positive in 64 (55%) patients and the ACPA was positive in 31 (26%) patients. The median DAS28 was 5,52 [2,91-7,81]. The medianUS-DAS28 was 5.29 [1.98- 7.83]. The comparison between US-DAS28 according to immunological status is showed in table 1.Table 1.US-DAS28 depending on RF and ACPA statusUS-DAS28pRF (+)5,290,90RF (−)5,26ACPA (+)5,310,80ACPA (−)5,29ConclusionsWe conclude that there was no significant difference of RA activity between seropositive or seronegative RA and also whether ACPA was positive or not. The analysis of bone damages should be compared in another study order to determinate the prognostic value of ACPA.ReferencesJung C, Jisuk B. Relation of rheumatoid factor and anti cyclic citrullined peptide antobody with disease activity in rheumatoid arthritis: cross sectional study. Rheumatol Int 2013.Disclosure of InterestNone declared
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