37 research outputs found
Is integrated 18F-FDG PET/MRI superior to 18F-FDG PET/CT in the differentiation of incidental tracer uptake in the head and neck area?
PURPOSE:We aimed to investigate the accuracy of 18F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging (18F-FDG PET/MRI) compared with contrast-enhanced 18F-FDG PET/computed tomography (PET/CT) for the characterization of incidental tracer uptake in examinations of the head and neck.METHODS:A retrospective analysis of 81 oncologic patients who underwent contrast-enhanced 18F-FDG PET/CT and subsequent PET/MRI was performed by two readers for incidental tracer uptake. In a consensus reading, discrepancies were resolved. Each finding was either characterized as most likely benign, most likely malignant, or indeterminate. Using all available clinical information including results from histopathologic sampling and follow-up examinations, an expert reader classified each finding as benign or malignant. McNemar’s test was used to compare the performance of both imaging modalities in characterizing incidental tracer uptake.RESULTS:Forty-six lesions were detected by both modalities. On PET/CT, 27 lesions were classified as most likely benign, one as most likely malignant, and 18 as indeterminate; on PET/MRI, 31 lesions were classified as most likely benign, one lesion as most likely malignant, and 14 as indeterminate. Forty-three lesions were benign and one lesion was malignant according to the reference standard. In two lesions, a definite diagnosis was not possible. McNemar’s test detected no differences concerning the correct classification of incidental tracer uptake between PET/CT and PET/MRI (P = 0.125).CONCLUSION:In examinations of the head and neck area, incidental tracer uptake cannot be classified more accurately by PET/MRI than by PET/CT
Synovitis and bone inflammation in early rheumatoid arthritis: high-resolution multi-pinhole SPECT versus MRI
PURPOSEWe aimed to assess the relationship between bone inflammation in multi-pinhole single-photon emission computed tomography (MPH-SPECT) and synovitis detected by magnetic resonance imaging (MRI) in early rheumatoid arthritis patients. MATERIALS AND METHODSMPH-SPECT with technetium dicarboxypropanedisphosphonate (Tc-99mDPD) and 3 Tesla MRI were performed in 10 early rheumatoid arthritis patients. Eighty finger joint sites were assessed for increased osteoblastic activity using visual and region-of-interest (ROI) analysis. Presence of joint inflammation in MRI was investigated using the subscores of the rheumatoid arthritis MRI score. RESULTSTc-99mDPD uptake was increased in 38 (47.5%) and 22 (27.5%) joint sites as determined by visual and ROI analysis, respectively. A total of 32 (84.2%) sites with increased bone metabolism showed a normal MRI bone signal. The MPHSPECT uptake ratio was elevated only in the subgroup with severe synovitis (P < 0.001). CONCLUSIONIn early rheumatoid arthritis, molecular imaging with MPHSPECT detects higher rates of inflammatory bone involvement compared to MRI. Our preliminary data suggest that osteitis is related to severe synovitis
Gas and dust cooling along the major axis of M 33 (HerM33es). Herschel/PACS [C II] and [O I] observations
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Context. M 33 is a gas rich spiral galaxy of the Local Group. Its vicinity allows us to study its interstellar medium (ISM) on linear scales corresponding to the sizes of individual giant molecular clouds.
Aims. We investigate the relationship between the two major gas cooling lines and the total infrared (TIR) dust continuum.
Methods. We mapped the emission of gas and dust in M 33 using the far-infrared lines of [CII] and [OI](63 mu m) and the total infrared continuum. The line maps were observed with the PACS spectrometer on board the Herschel Space Observatory. These maps have 50 pc resolution and form a similar to 370 pc wide stripe along its major axis covering the sites of bright HII regions, but also more quiescent arm and inter-arm regions from the southern arm at 2 kpc galacto-centric distance to the south out to 5.7 kpc distance to the north. Full-galaxy maps of the continuum emission at 24 mu m from Spitzer/MIPS, and at 70 mu m, 100 mu m, and 160 mu m from Herschel/PACS were combined to obtain a map of the TIR.
Results. TIR and [CII] intensities are correlated over more than two orders of magnitude. The range of TIR translates to a range of far ultraviolet (FUV) emission of G(0, obs)similar to 2 to 200 in units of the average Galactic radiation field. The binned [CII]/TIR ratio drops with rising TIR, with large, but decreasing scatter. The contribution of the cold neutral medium to the [CII] emission, as estimated from VLA HI data, is on average only 10%. Fits of modified black bodies to the continuum emission were used to estimate dust mass surface densities and total gas column densities. A correction for possible foreground absorption by cold gas was applied to the [OI] data before comparing it with models of photon dominated regions. Most of the ratios of [CII]/[OI] and ([CII]+[OI])/TIR are consistent with two model solutions. The median ratios are consistent with one solution at n similar to 2x10(2) cm(-3), G(0)similar to 60, and a second low-FUV solution at n similar to 10(4) cm(-3), G(0)similar to 1.5.
Conclusions. The bulk of the gas along the lines-of-sight is represented by a low-density, high-FUV phase with low beam filling factors similar to 1. A fraction of the gas may, however, be represented by the second solution. © C. Kramer et al. 2020M.R. and S.V. acknowledge support by the research projects AYA2014-53506-P and AYA2017-84897-P from the Spanish Ministerio de Economia y Competitividad, from the European Regional Development Funds (FEDER) and the Junta de Andalucia (Spain) grants FQM108. This study has been partially financed by the Consejeria de Conocimiento, Investigacion y Universidad, Junta de Andalucia and European Regional Development Fund (ERDF), ref. SOMM17/6105/UGR. FST thanks the Spanish Ministry of Economy and Competitiveness (MINECO) for support under grant number AYA2016-76219-P.Peer reviewe
Advantages of a combined rheumatoid arthritis magnetic resonance imaging score (RAMRIS) for hand and feet: does the RAMRIS of the hand alone underestimate disease activity and progression?
Diagnostic potential of PET/CT using a Ga-labelled prostate-specific membrane antigen ligand in whole-body staging of renal cell carcinoma: initial experience
Purpose To evaluate the diagnostic potential of whole-bodyPET/CT using a 68Ga-labelled PSMA ligand in renal cell carcinoma(RCC).Methods Six patients with histopathologically proven RCCunderwent 68Ga-PSMA PET/CT. Each PET/CT scan wasevaluated in relation to lesion count, location and dignity.SUVmax was measured in primary tumours and PETpositivemetastases. Tumour-to-background SUVmax ratios(TBRSUVmax) were calculated for primary RCCs in relationto the surrounding normal renal parenchyma. Metastasis-tobackgroundSUVmax ratios (MBRSUVmax) were calculatedfor PET-positive metastases in relation to gluteal muscle.Results Five primary RCCs and 16 metastases were evaluated.The mean SUVmax of the primary RCCs was 9.9 ± 9.2(range 1.7 – 27.2). Due to high uptake in the surrounding renalparenchyma, the mean TBRSUVmax of the primary RCCs wasonly 0.2 ± 0.3 (range 0.02 – 0.7). Eight metastases showed focal68Ga-PSMA uptake (SUVmax 9.9 ± 8.3, range 3.4 – 25.6).The mean MBRSUVmax of these PET-positive metastases was11.7 ± 0.2 (range 4.4 – 28.1). All PET-negative metastaseswere subcentimetre lung metastases.Conclusion 68Ga-PSMA PET/CT appears to be a promisingmethod for detecting RCC metastases. However, no additionaldiagnostic value in assessing the primary tumour was found
Dual-phase hybrid F-18-Fluoride Positron emission tomography/MRI in ankylosing spondylitis: Investigating the link between MRI bone changes, regional hyperaemia and increased osteoblastic activity
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Investigation of the Expression of Inflammatory Markers in Oral Biofilm Samples in Patients with Systemic Scleroderma and the Association with Clinical Periodontal Parameters—A Preliminary Study
Background: Systemic scleroderma (SSc) has multiple orofacial effects. The aim of this study was to analyze the expression of inflammatory mediators in biofilm samples. It was hypothesized that different expression levels and clinical associations might be drawn. Methods: A total of 39 biofilm samples from group 1 = SSc and group 2 = healthy control were examined for the expression levels of interleukin (IL)-2,-6, and -10; matrix metalloprotease (MMP)-9; and surface antigens CD90 and CD34 by quantitative real-time PCR and clinical parameters. Relative quantitative (RQ) gene expression was determined using the increment increment CT method. Results: The mean bleeding on probing values (p = 0.006), clinical attachment loss (CAL) (p = 0.009), gingival recession (p = 0.020), limited mouth opening (p = 0.001) and cervical tooth defects (p = 0.011) were significantly higher in group 1. RQ expressions of IL-2 and CD34 were significantly lower, IL-6, MMP-9, and CD90 were significantly higher. There was a significant positive correlation of IL-6/MMP-9 and negative correlation of mouth opening/CAL and IL-6/CAL. Conclusion: Different expression levels of IL-2, IL-6, MMP-9, CD34 and CD90 were detected in biofilm samples from patients with SSc compared to control. An immunological correlation to the clinical parameters of mouth opening and CAL was shown; thus, we conclude that SSc might have an impact on periodontal tissues
Investigation of the Expression of Inflammatory Markers in Oral Biofilm Samples in Patients with Systemic Scleroderma and the Association with Clinical Periodontal Parameters—A Preliminary Study
Background: Systemic scleroderma (SSc) has multiple orofacial effects. The aim of this study was to analyze the expression of inflammatory mediators in biofilm samples. It was hypothesized that different expression levels and clinical associations might be drawn. Methods: A total of 39 biofilm samples from group 1 = SSc and group 2 = healthy control were examined for the expression levels of interleukin (IL)-2,-6, and -10; matrix metalloprotease (MMP)-9; and surface antigens CD90 and CD34 by quantitative real-time PCR and clinical parameters. Relative quantitative (RQ) gene expression was determined using the ∆∆CT method. Results: The mean bleeding on probing values (p = 0.006), clinical attachment loss (CAL) (p = 0.009), gingival recession (p = 0.020), limited mouth opening (p = 0.001) and cervical tooth defects (p = 0.011) were significantly higher in group 1. RQ expressions of IL-2 and CD34 were significantly lower, IL-6, MMP-9, and CD90 were significantly higher. There was a significant positive correlation of IL-6/MMP-9 and negative correlation of mouth opening/CAL and IL-6/CAL. Conclusion: Different expression levels of IL-2, IL-6, MMP-9, CD34 and CD90 were detected in biofilm samples from patients with SSc compared to control. An immunological correlation to the clinical parameters of mouth opening and CAL was shown; thus, we conclude that SSc might have an impact on periodontal tissues
Silent progression in patients with rheumatoid arthritis: is DAS28 remission an insufficient goal in RA? Results from the German Remission-plus cohort
BACKGROUND: Remission is arguably the ultimate therapeutic goal in rheumatoid arthritis (RA). Applying modern strategies, clinical remission can be achieved in a substantial number of patients with early RA (ERA). Even in those patients, the number and scope of erosions can increase. We, therefore, investigated the value of MRI for the detection of radiological progression in patients with DAS28 improvement and/or clinical remission of the German Remission-plus cohort. METHODS: Data-sets of 80 RA patients (according to 2010 ACR/EULAR criteria) from the Remission-plus study cohort, who fulfilled the following criteria, were retrospectively analysed: availability of two consecutive MRI scans (low-field MRI, follow-up interval 1 year) of the clinically dominant hand and wrist, and the presence of DAS28 (CRP) scores at both time points, which was used to assess disease activity. RESULTS: Seventy-one of the 80 investigated patients presented a numerical improvement of the DAS28 (CRP) after 12 months (DAS28(CRP) T0 average (Ø) 4.96, SD 1.2; DAS28 T4 (12 month) Ø 2.6, SD 1.0), 73% of them also improved in the RAMRIS-Score, while 24% demonstrated an increase despite DAS28 improvement and 3% showed equal values. 48% of patients who improved in the DAS28 reached EULAR remission. 41% of these patients had an increase in the RAMRIS Erosion-subscore after 12 months. When considering EULAR response criteria (non-response (n = 7), moderate response (n = 19), good response (n = 45)), an increase of erosions was found in 71.4% of non-responders, 52.6% of moderate responders, and 31.1% of good responders after 12 months, all compared to baseline. CONCLUSION: Up to 40% of patients in this study demonstrated a progressive erosive disease detected by MRI despite DAS28 improvement or EULAR remission. Future studies are needed to determine the prognostic clinical impact of disease progression in MRI despite clinical remission, and to investigate if DAS28 remission may be an insufficient therapeutic goal and should be accompanied by MRI remission criteria