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991.
Suad Aljohani Robert Gaudin Julian Weiser Matthias Tröltzsch Michael Ehrenfeld Gabriele Kaeppler Ralf Smeets Sven Otto 《Journal of cranio-maxillo-facial surgery》2018,46(9):1515-1525
Purpose
Osteonecrosis of the jaw has been recently reported in patients receiving denosumab for the treatment of metastatic bone disease and osteoporosis. It is essential to investigate this disease as a new osteonecrosis entity in order to recognize its optimal management strategies.Materials and Methods
A total of 63 cases of denosumab-related osteonecrosis of the jaw (DRONJ) diagnosed at two clinical centres were retrospectively reviewed. Demographics, comorbidities, antiresorptive medication use, local preceding event, location, DRONJ stage, treatment and treatment outcomes were analyzed.Results
In all, 69 MRONJ lesions in 63 patients were diagnosed. The mean patient age was 70 ± 9 years. Denosumab was the only received antiresorptive medication in 50.8% of the patients. Discontinuation of denosumab prior to treatment was recorded for 66.7% of the patients, with a mean period of 6 ± 3.4 months. Stage 2 was the most common stage of the disease (71%). The lesions were predominantly located in the mandible (63.5%). The most common preceding local event was extraction (55.6%). Surgical treatment was performed in 95.7% of the cases, while purely conservative treatment was performed in 4.3%. DRONJ healed after surgical treatment in 71.7% of the treated lesions. Complete mucosal healing was achieved in 77.2% of the lesions treated with fluorescence-guided surgery (17/22). Clinical characteristics and treatment outcomes were not significantly different between patients with and without previous intake of bisphosphonates.Conclusion
DRONJ is more prevalent at extraction and local infection sites in cancer patients. Within the limitation of this study, surgical treatment, particularly fluorescence-guided surgery, appears to be effective for the management of DRONJ. The prior use of bisphosphonates does not seem to affect severity nor the treatment success rate of DRONJ. 相似文献992.
Rene Rothweiler Joerg Bayer Joern Zwingmann Norbert P. Suedkamp Johannes Kalbhenn Rainer Schmelzeisen Ralf Gutwald 《Journal of cranio-maxillo-facial surgery》2018,46(2):283-287
Finding the correct point of time for operative treatment of facial fractures in multiply injured people remains one of the most important challenges in modern emergency medicine. Findings relating to pathophysiological mechanisms after severe trauma argue against the early operative treatment of non-life-threatening injuries. Our retrospective analysis investigated the effects on complications and outcome of different time points for operative treatment of maxillofacial fractures in multiply injured patients.Over a period of 10 years (2003–2012) we could identify 1543 patients, of whom 553 had fractures of the facial skull. 168 of the facial fracture patients were operated on their fractures, 97 at a time later than 72 h. Despite the delayed time of operation, the patients showed fewer complications (21.6% vs 25.4%). This resulted in fewer additional stays in hospital (9.3% vs 11.3%), and also in fewer plate removals (23.7% vs 33.8%). We conclude that delayed operative fracture treatment does not lead to more complications. The optimal time for operative treatment has to be determined individually as the earliest point at which no adverse effects from comorbidities are expected. 相似文献
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Objectives
To compare respiratory-triggered, free-breathing, and breath-hold DWI techniques regarding (1) image quality, and (2) signal intensity (SI) and ADC measurements in pancreatic ductal adenocarcinoma (PDAC).Methods
Fifteen patients with histopathologically proven PDAC underwent DWI prospectively at 1.5?T (b?=?0, 50, 300, 600 and 1,000?s/mm2) with the three techniques. Two radiologists, independently and blindly, assigned total image quality scores [sum of rating diffusion images (lesion detection, anatomy, presence of artefacts) and ADC maps (lesion characterisation, overall image quality)] per technique and ranked them. The lesion SI, signal-to-noise ratio, mean ADC and coefficient of variation (CV) were compared.Results
Total image quality scores for respiratory-triggered, free-breathing and breath-hold techniques were 17.9, 16.5 and 17.1 respectively (respiratory-triggered was significantly higher than free-breathing but not breath-hold). The respiratory-triggered technique had a significantly higher ranking. Lesion SI on all b-values and signal-to-noise ratio on b300 and b600 were significantly higher for the respiratory-triggered technique. For respiratory-triggered, free-breathing and breath-hold techniques the mean ADCs were 1.201, 1.132 and 1.253?×?10-3?mm2/s, and mean CVs were 8.9, 10.8 and 14.1?% respectively (respiratory-triggered and free-breathing techniques had a significantly lower mean CV than the breath-hold technique).Conclusion
In both analyses, respiratory-triggered DWI showed superiority and seems the optimal DWI technique for demonstrating PDAC.Key Points
? Diffusion-weighted magnetic resonance imaging is increasingly used to detect pancreatic cancer ? Images are acquired using various breathing techniques and multiple b-values ? Breathing techniques used: respiratory-triggering, free-breathing and breath-hold ? Respiratory-triggering seems the optimal breathing technique for demonstrating pancreatic cancer 相似文献996.
Abou-Elkacem L Björn S Doleschel D Ntziachristos V Schulz R Hoffman RM Kiessling F Lederle W 《European radiology》2012,22(9):1955-1962
Objectives
To compare mesoscopic epi-fluorescence tomography (MEFT) and EPRI-illumination reflectance imaging (EPRI) for quantitative tumour size assessment in mice.Methods
Tumour xenografts of green/red fluorescent protein (GFP/RFP)-expressing colon cancer cells were measured using MEFT, EPRI, ultrasound (US) and micro computed tomography (μCT) at day 14 post-injection (n?=?6). Results from MEFT and EPRI were correlated with each other and with US and μCT (reference methods). Tumour volumes were measured ex vivo by GFP and RFP fluorescence imaging on cryoslices and compared with the in vivo measurements.Results
High correlation and congruency were observed between MEFT, US and μCT (MEFT/US: GFP: r 2?=?0.96; RFP: r 2?=?0.97, both P?0.05; MEFT/μCT: GFP: r 2?=?0.93; RFP: r 2?=?0.90; both P?0.05). Additionally, in vivo MEFT data were highly correlated and congruent with ex vivo cryoslice imaging results (GFP: r 2?=?0.96; RFP: r 2?=?0.99; both P?0.05). In comparison, EPRI significantly overestimated tumour volumes (P?0.05), although there was a significant correlation with US and μCT (EPRI/US: GFP: r 2?=?0.95; RFP: r 2?=?0.94; both P?0.05; EPRI/μCT GFP: r 2?=?0.86; RFP: r 2?=?0.86; both P?0.05).Conclusions
Fluorescence distribution reconstruction using MEFT affords highly accurate three-dimensional (3D) tumour volume data showing superior accuracy compared to EPRI. Thus, MEFT is a very suitable technique for quantitatively assessing fluorescence distribution in superficial tumours at high spatial resolution.Key Points
? Mesoscopic epi-fluorescence tomography (MEFT) is an important new molecular imaging technique. ? MEFT allows accurate size determination of superficial tumours with high resolution. ? MEFT is a suitable technique for longitudinal assessment of tumour growth. ? MEFT allows 3D reconstruction and quantification of fluorescence distributions. 相似文献997.
Center of pressure (COP) path length evaluation was commonly applied to measure postural sway and usually obtained from gold standard force plates. Thus, we comparatively investigated the feasible and less-expensive GKS® balance system (GKS) with the Kistler® force platform (KIS).34 non-specifically trained but active adults (14 males, 20 females, age: 25.4 ± 4.8 years; weight: 69.3 ± 12.3 kg; height: 1.75 ± 0.09 m, sports activity: 5.8 ± 3.6 hours per week) were randomly tested on both devices during double and single limb stance with opened and closed eyes.Irrespective of the analysed time frame, repeated measures analyses of variances revealed higher path length readings for GKS compared to KIS for 30 s (F = 6.8, p = 0.01) and 10 s (F = 21.2, p = 0.001). Large effect sizes of the COP path length differences between GKS and KIS decreased from easy tasks (double limb, eyes open; d30-s = 2.55, d10-s = 2.04) to the most severe task (single limb, eyes closed; d30-s = 0.02, d10-s = 0.23). According to Bland and Altman, the limits of agreements indicated a high random variability component (between 29%, double limb, eyes open and 67%, single limb, eyes closed). The overall intraclass correlation coefficients (ICC) across all four standing balance tasks were moderate for the 30 s- (0.57) as well as the 10 s-analysis (0.65).In conclusion, the COP path length displacements obtained from the GKS balance system seem to differ with a considerable random variability from Kistler force platform data. Thus, measurements of the evaluated devices should not be used interchangeably. Further methodological investigations regarding balance measures seem warranted. 相似文献
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Metastatic lesions in the superior vena cava and the right atrium are difficult to diagnose: in computed tomography (CT), they are easily misinterpreted as artifacts, and the same region may be difficult to access using echocardiography. We present a case of asymptomatic metastasis of a malignant melanoma which was overlooked initially due to deficiencies in imaging. Using 18F-fluorodeoxyglucose positron emission tomographyCT, the metastasis was clearly identified and finally treated successfully. We discuss the diagnostic value of the various imaging modalities for intracardiac masses. 相似文献