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21.
Summary ? Background. The anterior approach for cervical discectomy with methacrylate-implant involves manipulations on vertebral bodies and ligaments.
Foreign materials like methacrylate and fibrin sponge are inserted. On postoperative MRI it may be difficult to differentiate
pathological from “normal” findings caused by routine manipulations.
Method. In this study 14 patients free of symptoms after anterior discectomy with methacrylate-implant were examined clinically
and a MRI was performed on the 7th day after surgery and again after a 6 month follow-up. All patients had an uneventful recovery
and no signs of inflammation after surgery.
Findings. Independent of the underlying pathology (e.g. soft or hard disc) 73% of the patients had a signal reduction within the vertebral
bodies adjacent to the operated disc on T1-weighted spin-echo images on the 7th postoperative day. Signal intensities were
normal after 6 months in all patients. Remarkable metal artifacts were present in one patient only. The methacrylate-implant
could be identified as a hypo-intense structure on all sequences at any time without artifacts. In 80% of the cases a hyperintensity
was found on T2-weighted images between the methacrylate-implant and the dura on the 7th postoperative day. A protrusion of the posterior ligament was present at the level of the operated disc on day 7 after surgery,
which had resolved completely 6 months later. This may mimic residual disc tissue or osteophytes early after surgery.
Interpretation. It is very important to know this “normal” postoperative appearance of the cervical spine in order to avoid misinterpretations. 相似文献
22.
23.
AIMS: To analyze diagnosis and treatment of four advanced abdominal pregnancies in a low-resource setting of a developing country. METHODS: Extrauterine pregnancies occurring between 1997 and 2003 were identified from hospital records of the Mikumi Health Center in Tanzania/East Africa. RESULTS: A total of 45 extrauterine pregnancies were diagnosed four of which were advanced and located in the abdominal cavity. At the time of diagnosis, pregnancies were at 33, 34, 36 and 39 weeks of gestation, respectively. All four mothers survived but three of four fetuses died. One child is alive and well three years after delivery. CONCLUSION: Abdominal pregnancy is rather difficult to detect in a low-resource setting of a developing country. Persistent abdominal pain and tenderness, as well as fetal movements in the upper abdomen associated with abnormal fetal lie, may lead to its diagnosis. Localizing the fetal heart sounds in the maternal epigastrium especially in patients with abdominal pain may also be helpful in diagnosing an abdominal pregnancy. In addition, the lack of cervical changes or a displaced cervix should lead to the suspicion of an abdominal pregnancy. 相似文献
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25.
Anne Krogh Nhr Morten Lindow Annika Forsingdal Samuel Demharter Troels Nielsen Raimund Buller Ida Moltke Morana Vitezic Anders Albrechtsen 《Neuropsychopharmacology》2021,46(7):1324
A better understanding of the biological factors underlying antidepressant treatment in patients with major depressive disorder (MDD) is needed. We perform gene expression analyses and explore sources of variability in peripheral blood related to antidepressant treatment and treatment response in patients suffering from recurrent MDD at baseline and after 8 weeks of treatment. The study includes 281 patients, which were randomized to 8 weeks of treatment with vortioxetine (N = 184) or placebo (N = 97). To our knowledge, this is the largest dataset including both gene expression in blood and placebo-controlled treatment response measured by a clinical scale in a randomized clinical trial. We identified three novel genes whose RNA expression levels at baseline and week 8 are significantly (FDR < 0.05) associated with treatment response after 8 weeks of treatment. Among these genes were SOCS3 (FDR = 0.0039) and PROK2 (FDR = 0.0028), which have previously both been linked to depression. Downregulation of these genes was associated with poorer treatment response. We did not identify any genes that were differentially expressed between placebo and vortioxetine groups at week 8 or between baseline and week 8 of treatment. Nor did we replicate any genes identified in previous peripheral blood gene expression studies examining treatment response. Analysis of genome-wide expression variability showed that type of treatment and treatment response explains very little of the variance, a median of <0.0001% and 0.05% in gene expression across all genes, respectively. Given the relatively large size of the study, the limited findings suggest that peripheral blood gene expression might not be the best approach to explore the biological factors underlying antidepressant treatment.Subject terms: Predictive markers, Depression 相似文献
26.
Alberto Addis Maxime Gaasch Alois J Schiefecker Mario Kofler Bogdan Ianosi Verena Rass Anna Lindner Gregor Broessner Ronny Beer Bettina Pfausler Claudius Thom Erich Schmutzhard Raimund Helbok 《Journal of cerebral blood flow and metabolism》2021,41(2):359
Elevated body temperature (Tcore) is associated with poor outcome after subarachnoid hemorrhage (SAH). Brain temperature (Tbrain) is usually higher than Tcore. However, the implication of this difference (Tdelta) remains unclear. We aimed to study factors associated with higher Tdelta and its association with outcome. We included 46 SAH patients undergoing multimodal neuromonitoring, for a total of 7879 h of averaged data of Tcore, Tbrain, cerebral blood flow, cerebral perfusion pressure, intracranial pressure and cerebral metabolism (CMD). Three-months good functional outcome was defined as modified Rankin Scale ≤2. Tbrain was tightly correlated with Tcore (r = 0.948, p < 0.01), and was higher in 73.7% of neuromonitoring time (Tdelta +0.18°C, IQR −0.01 – 0.37°C). A higher Tdelta was associated with better metabolic state, indicated by lower CMD-glutamate (p = 0.003) and CMD-lactate (p < 0.001), and lower risk of mitochondrial dysfunction (MD) (OR = 0.2, p < 0.001). During MD, Tdelta was significantly lower (0°C, IQR −0.2 – 0.1; p < 0.001). A higher Tdelta was associated with improved outcome (OR = 7.7, p = 0.002). Our study suggests that Tbrain is associated with brain metabolic activity and exceeds Tcore when mitochondrial function is preserved. Further studies are needed to understand how Tdelta may serve as a surrogate marker for brain function and predict clinical course and outcome after SAH. 相似文献
27.
Dietmann A Helbok R Lackner P Issifou S Lell B Matsiegui PB Reindl M Schmutzhard E Kremsner PG 《The Journal of infectious diseases》2008,197(11):1614-1620
BACKGROUND: Molecular mechanisms involved in the pathogenesis of severe malaria caused by Plasmodium falciparum are not fully understood. Matrix metalloproteinases (MMPs) are enzymes that proteolytically degrade both the extracellular matrix and nonmatrix substances with various functions in the modulation of immune response. The key inhibitors of MMPs are the tissue inhibitors of metalloproteinases (TIMPs). METHODS: We studied levels of MMP-8, MMP-9, TIMP-1, and TIMP-2 on admission and after 24 h, using an enzyme-linked immunosorbent assay, in serum specimens from 50 Gabonese children with severe malaria, 43 children with uncomplicated malaria, and 27 healthy control children. RESULTS: Serum MMP-8 and TIMP-1 levels were significantly higher in the severe malaria and uncomplicated malaria groups, compared with those in the control group (P < .001). TIMP-1 levels were significantly higher in patients with severe malaria, compared with those in patients with uncomplicated malaria (P < .001). High TIMP-1 levels were significantly correlated with malaria severity, as determined by the simplified multiorgan dysfunction score (Spearman rank-correlation coefficient, 0.55; P < .001). CONCLUSIONS: TIMP-1 is associated with signs and symptoms of severe malaria. MMP-8 levels are elevated in patients with severe or uncomplicated P. falciparum malaria. MMPs and TIMPs may be relevant in the pathogenesis of severe malaria, either as proteolytic enzymes that degrade the extracellular matrix or as effectors and regulators of the immune response. 相似文献
28.
Martin Lang Rüdiger Brennecke Michael Haude Ulrich Renneisen Raimund Erbel Jürgen Meyer 《The International Journal of Cardiac Imaging》1995,11(2):105-115
In clinical applications the analysis of X-ray contrast densograms acquired in regions of interest (ROI's) over the myocardium is disturbed by many complex factors. For this reason we acquire redundant densogram information for quality control before extracting densitometric parameters. In our approach, initially some stable measures of quality for densograms are used to lower the influence of poor quality densograms by a quality weighted averaging. For example a shape quality measure, Q1, is calculated using regions of optimal and minimal acceptable quality defined with respect to a prototype densogram. Not a few myocardial ROI's yield densograms that differ from single-source densograms (SSD's) due to e.g. superposition of different perfusion beds or the position of the ROI relative to the coronary sinus or stenoses. This might result in a densogram shape with oscillating or plateau behavior. For densograms of a such general shape many parameters defined in the usual way do not depend smoothly on the densogram values. The conventional definitions of some parameters (appearance time, rise time) are therefore extended for application to multi-maxima densograms as well as to SSD's. These new methods are evaluated using digitized clinical angiocardiograms and are applied to parametric imaging (pixeldensograms) in a slightly modified way. Taking into account the densogram quality, its shape and its origin results in a considerable improvement both for densitometry and parametric imaging of myocardial perfusion.Abbreviations AP
appearance time
- Dmax
maximum density
- LAO 60°
left anterior oblique 60° projection
- LCA
left coronary artery
- MIRT
mean integrated rise time
- MTT
mean transit time
- RAO 30°
right anterior oblique 60° projection
- RCA
right coronary artery
- ROI
region of interest
- RT
rise time
- SSD
single-source densogram
- THM
time of half-maximum, tmax - time of maximum 相似文献
29.
Theodor Baars Ursula Neumann Mona Jinawy Stefanie Hendricks Jan-Peter Sowa Julia K?lsch Mona Riemenschneider Guido Gerken Raimund Erbel Dominik Heider Ali Canbay 《Medicine》2016,95(6)
Detection of high-risk subjects in acute myocardial infarction (AMI) by noninvasive means would reduce the need for intracardiac catheterization and associated complications. Liver enzymes are associated with cardiovascular disease risk. A potential predictive value for liver serum markers for the severity of stenosis in AMI was analyzed.Patients with AMI undergoing percutaneous coronary intervention (PCI; n = 437) were retrospectively evaluated. Minimal lumen diameter (MLD) and percent stenosis diameter (SD) were determined from quantitative coronary angiography. Patients were classified according to the severity of stenosis (SD ≥ 50%, n = 357; SD < 50%, n = 80). Routine heart and liver parameters were associated with SD using random forests (RF). A prediction model (M10) was developed based on parameter importance analysis in RF.Age, alkaline phosphatase (AP), aspartate aminotransferase (AST), and MLD differed significantly between SD ≥ 50 and SD < 50. Age, AST, alanine aminotransferase (ALT), and troponin correlated significantly with SD, whereas MLD correlated inversely with SD. M10 (age, BMI, AP, AST, ALT, gamma-glutamyltransferase, creatinine, troponin) reached an AUC of 69.7% (CI 63.8–75.5%, P < 0.0001).Routine liver parameters are associated with SD in AMI. A small set of noninvasively determined parameters can identify SD in AMI, and might avoid unnecessary coronary angiography in patients with low risk. The model can be accessed via http://stenosis.heiderlab.de. 相似文献
30.
Intracardiac echocardiography: an ideal guiding tool for device closure of interatrial communications. 总被引:4,自引:0,他引:4
Thomas Bartel Thomas Konorza Ulrich Neudorf Tiko Ebralize Holger Eggebrecht Achim Gutersohn Raimund Erbel 《European journal of echocardiography》2005,6(2):92-96
BACKGROUND: This study sought to evaluate safety and radiation exposure when using intracardiac echocardiography (ICE) in comparison to transesophageal echocardiography (TEE) in order to guide transcatheter closure of interatrial communications. METHODS: Eighty patients (44 males, 36 females, mean age 46, SD 13 years) undergoing device closure of atrial septal defect (n=12) or patent foramen ovale (n=68) had the procedure guided by ICE (n=50, group 1) or TEE (n=30, group 2). In group 1, all procedural stages were completely guided by ICE, including imaging of the interatrial communication during balloon sizing, device unfolding and release, and during the final check for adequate positioning. In group 2, exclusive implantation of devices was guided by use of TEE. RESULTS: Especially, the spatial relationship between device and cardiac structures (e.g. the ascending aorta, the interatrial septum and the superior vena cava) was accurately demonstrated in group 1. Image resolution provided by ICE was superior to that of TEE. No severe complications, including any related to ICE, were seen. Fluoroscopy time (FT) and procedure time (PT) were shorter in group 1 than in group 2 (FT: 5.5+/-1.5 min vs. 9.3+/-1.6 min, P<0.0001; PT: 31.9+/-4.6 min vs. 38.8+/-5.8 min, P<0.01). Neither sedation nor anesthesia was required in group 1. CONCLUSIONS: ICE is a safe tool to guide device closure of interatrial communications. For the patient, procedural stress and radiation exposure are negligible. ICE can be considered the guiding tool of choice for device closure, particularly when long or repeated echocardiographic viewing is required. 相似文献