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1.
We conducted an in vitro performance study to test the flow-directed Spinnaker microcatheter for potential endovascular embolizations with Ethibloc as embolic agent. We performed in vitro testing using 50 Spinnaker 1.8F hydrophilic infusion microcatheters of three different types. As embolic agent, different mixtures of Ethibloc and Lipiodol (E/L 1:1, 1:2, 1:3) were used. In an in vitro setting, each catheter was injected to a maximum of ten times (E/L 1:1, n = 20 catheters; E/L 1:2, n = 20; E/L 1:3, n = 10). In addition, we evaluated the thinner Spinnaker 1.5F microcatheter (165/20, n = 10). Five Spinnaker 1.5F catheters were each injected with a mixture of Ethibloc and Lipiodol (E/L 1:2 and 1:3). When a mixture of E/L 1:1 was used, 9 of 20 (45%) Spinnaker 1.8F microcatheters ruptured distally near the tip of the microcatheter, each during injection nos. 5-9. One Spinnaker 1.8F was distally occluded after the fifth injection. With a mixture of E/L 1:2, 4 of 20 (20%) Spinnaker 1.8F microcatheters ruptured distally, during injection no. 6 (n = 2), 7 (n = 1), and 8 (n = 1). With a mixture of E/L 1:3, all ten Spinnaker 1.8F microcatheters could be injected without any problems. All ten microcatheters of the thinner Spinnaker 1.5F ruptured (10-18 cm proximally to the catheter tip). This in vitro study using the flow-directed Spinnaker microcatheter revealed that microcatheters can rupture. The Spinnaker 1.8F can rupture when a mixture of Ethibloc and Lipiodol 1:1 or 1:2 and more than four injections are used. The Spinnaker 1.8F does not rupture when a mixture of E/L 1:3 is used, or with a mixture of E/L 1:1 or 1:2 and injecting to a maximum of four times. The Spinnaker 1.5F microcatheter is not suitable for embolizations using Ethibloc. For embolizations with Ethibloc we therefore recommend the use of a guidewire-directed microcatheter.  相似文献   

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BackgroundThis in vitro study aimed to assess carious lesions on root surfaces using quantitative light-induced fluorescence (QLF) and to compare the readings with axial lesion depth on µCT.MethodsThe root surfaces of 107 extracted human teeth were included after visual-tactile inspection. For further analysis, the following parameters were assessed: clinical findings (non-cavitated: leathery or hard, cavitated), QLF- (QLF-D Biluminator 2+), and µCT-images (Bruker Skyscan 1172). The shape of the undamaged tooth surface of the cavitated lesions was virtually re-constructed during µCT analysis. Clinical surface texture,% fluorescence loss, and lesion depth (µCT) were determined. Statistical analysis: chi²-test, Spearman-Rho test, regression analysis.Results∆F was significantly lower in non-cavitated leathery (-50.37 ± 15.10) and cavitated (-61.23 ± 9.92) compared to non-cavitated surfaces with a hard texture (-17.04 ± 16.10, p < 0.01). For non-cavitated surfaces, a negative correlation was observed between ∆F and lesion depth in µCT images regardless of texture (-0.748, p < 0.01). Regression analysis revealed that ∆F predicted lesion depth in µCT for non-cavitated surfaces (β: 0.703, CI95: 0.67–-0.43, p < 0.01).ConclusionThe percentage of fluorescence loss (∆F) in QLF predicted lesion depth of non-cavitated demineralized root surfaces. Therefore, QLF can be recommended for estimating the lesion depth of carious root lesions and seems to expand the possibilities of follow-up and lesion monitoring, especially for non-cavitated surfaces.  相似文献   

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A retrospective review of homicide cases was undertaken from the mortuary records at the National Hospital in Apia, Samoa, over a five-year period from June 2011 to May 2016. Thirty-three cases were found consisting of 27 males and six females (one with gender not specified; M:F = 4.5:1) with an age range of 19 to 61 years, average 34.1 years (males – 19–57 years, average 33.8 years; females 23–61 years, average 35.0 years). This gave an approximate rate of 3.5 homicides/100,000 people/year. The cases consisted of deaths due to blunt force head trauma: N = 21 (63.6%; two with drowning); sharp force trauma: N = 8 (24.2%; four stab wounds, four chop/machete wounds); gunshot wounds: N = 2 (6.1%); and neck compression: N = 2 (6.1%). This study has demonstrated a particularly high number of deaths due to blunt force trauma and a relatively low number of firearm-related deaths in Samoa in recent years.  相似文献   

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IntroductionBreast compression during mammographic examinations improves image quality and patient management. Several studies have been conducted to assess compression force variability among practitioners in order to establish compression guidelines. However, no such study has been conducted in Ghana. This study aims to investigate the compression force variability in mammography in Ghana.MethodsThis retrospective study used data gathered from 1071 screening and diagnostic mammography patients from January, 2018–December, 2019. Data were gathered by seven radiographers at three centers. Compression force, breast thickness and practitioners' years of work experience were recorded. Compression force variability among practitioners and the correlation between compression force and breast thickness were investigated.ResultsMean compression force values recorded for craniocaudal (CC) (17.2 daN) and mediolateral oblique (MLO) (18.2 daN), were within the recommended values used by western countries. Most of the mammograms performed – 80% – were within the National Health Service Breast Screening Programme (NHSBSP) range. However, 65% were above the Norwegian Breast Cancer Screening Programme (NBCSP) range. Compression forces varied significantly (p = 0.0001) among practitioners. Compression forces increased significantly (p = 0.0001) with the years of work experience. A weak negative correlation (r = ?0.144) and a weak positive correlation (r = 0.142) were established between compression force and breast thickness for CC and MLO projections respectively.ConclusionThis initial study confirmed that although wide variations in compression force exist among practitioners in Ghana, most practitioners used compression forces broadly within the range set by the NHSBSP. As no national guidelines for compression force currently exist in Ghana, provision of these may help to reduce the range of variations recorded.Implications for practiceConfirmation of variations in compression will guide future practice to minimize image quality disparities and improve quality of care.  相似文献   

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《Radiography》2023,29(2):450-455
IntroductionA number of Norwegian radiographers have attended an advanced programme of education and training in musculoskeletal reporting, some in the UK and some in Norway. The aim of this study was to examine how reporting radiographers, radiologists and managers experienced the education, competence, and role of reporting radiographers in Norway. To our knowledge, the role and function of reporting radiographers in Norway has not yet been explored.MethodsThe study had a qualitative design and was based on eleven individual interviews of reporting radiographers, radiologists, and managers. The participants represented five different imaging departments from four hospital trusts in Norway. The interviews were analyzed using inductive content analysis.ResultsThe analysis identified two main categories: “Education and training”, and “The reporting radiographer”. The subcategories were: “Education”, “Training”, “Competence”, and “The new role”.The study found the program to be demanding, challenging, and time-consuming. However, the reporting radiographers described it as motivating because they gained new competence. The competence of reporting radiographers was regarded as adequate. The participants found that reporting radiographers had a unique competence in both image acquisition and reporting, and they were described as a missing link between radiographers and radiologists.ConclusionReporting radiographers are experienced as an asset for the department. Reporting radiographers not only contribute to musculoskeletal imaging reports but are also important for collaboration, training, and professional development in imaging, and in collaborating with orthopedics. This was seen to increase the quality of musculoskeletal imaging.Implications for practiceReporting radiographers are a valuable resource in image departments, especially in smaller hospitals where the shortage of radiologists is noticeable.  相似文献   

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Background

The use of photoactivated disinfection has had a significant medical and technological effect in bacterial inactivation, as an alternative to conventional antimicrobial methods. The main goal of this study was to investigate the effect of photoactivated disinfection on Streptococcus mutans, when Radachlorin® was used as a photosensitizer.

Methods

Streptococcus mutans samples of two different initial concentrations were treated with Radachlorin® gel (0.1%), irradiated by the light of a He–Ne laser (633 nm), with energy density of 6 J/cm2, and cell viability was evaluated after culturing.

Results

It was observed that the combination of Radachlorin® and laser was more effective than Radachlorin® or laser alone (p < 0.05), in reduction of S. mutans and Radachlorin® was cytotoxic, in the dark, only for the lower concentration of bacteria. Lower concentration of S. mutans resulted in higher amount of killing, in the case of using Radachlorin® with or without laser.

Conclusions

The photoactivation of Radachlorin® using a He–Ne laser could inactivate S. mutans to a significant level. In addition Radachlorin® might be cytotoxic in the dark, for the lower concentration of bacteria.  相似文献   

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The purpose of this study was to evaluate Fullerene as a therapeutic photosensitizer in the treatment of atherosclerosis. An atherosclerotic experimental rabbit model was prepared by causing intimal injury to bilateral external iliac arteries using balloon expansion. In four atherosclerotic rabbits and one normal rabbit, polyethylene glycol-modified Fullerene (Fullerene-PEG) was infused into the left external iliac artery and illuminated by light emitting diode (LED), while the right external iliac artery was only illuminated by LED. Two weeks later, the histological findings for each iliac artery were evaluated quantitatively and comparisons were made among atherosclerotic Fullerene+LED artery (n = 4), atherosclerotic light artery (n = 4), normal Fullerene+LED artery (n = 1), and normal light artery (n = 1). An additional two atherosclerotic rabbits were studied by fluorescence microscopy, after Fullerene-PEG-Cy5 complex infusion into the left external iliac artery, for evaluation of Fullerene-PEG incorporated within the atherosclerotic lesions. The degree of atherosclerosis in the atherosclerotic Fullerene+LED artery was significantly (p < 0.05) more severe than that in the atherosclerotic LED artery. No pathological change was observed in normal Fullerene+LED and LED arteries. In addition, strong accumulation of Fullerene-PEG-Cy5 complex within the plaque of the left iliac artery of the two rabbits was demonstrated, in contrast to no accumulation in the right iliac artery. We conclude that infusion of a high concentration of Fullerene-PEG followed by photo-illumination resulted not in a suppression of atherosclerosis but in a progression of atherosclerosis in experimental rabbit models. However, this intervention showed no adverse effects on the normal iliac artery.  相似文献   

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Facial reconstruction is a technique used in forensic anthropology to identify an unknown person. Various methods used for facial reconstruction are drawings, sculpture and computer aided image building which is mainly based on facial soft tissue thickness measurement. Several methods have been established for measuring facial soft tissue thickness (FSTT) with each one having certain limitations. There is limited data available on FSTT among South Indian population. Hence the present study was ventured to determine the FSTT among South Indian adults and also to find FSTT difference between male and female.308 subjects of South Indian origin (18–27years) having full set of permanent dentition who require orthodontic treatment were included in the study. Subjects were assessed for Body Mass Index (BMI) and diagnostic digital x-ray of lateral cephalogram (LC), Lateral oblique (LO) view and posterior-anterior (PA) view was obtained. The digital image was transferred to Adobe Photoshop CS4 software and 23 different soft tissue points were measured.Mean FSTT was more in males compared to females except for three landmarks. Statistically significant difference was observed in 20 landmarks when height and weight was compared in males, whereas in females only 12 landmarks showed significant difference. BMI showed good correlation with FSTT in both males and females, which was confirmed by linear regression. The best regressor in terms of estimating FSTT in association with age/sex/BMI were nasion, sub nasale, labial superioris, labrale inferius, gnathion, inferior border of zygomatic, right and left gonion. Stepwise discriminant analysis using all variables showed 94.8% of overall accuracy in sex determination.The observation of present study suggests that LO and PA view along with LC gives information regarding mean FSTT among South Indian population. Even though BMI plays a dominant role in determining FSTT, but age, sex, height and weight should also be considered with care while facial reconstruction. Additionally the present regression equation contributes towards increase in the specificity of the tissue depths and can be used in real cases by allowing the practitioners to calculate individual tissue depth.  相似文献   

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The Guglielmi detachable coil (GDC) has been generally accepted for treatment of intracranial aneurysms. Preclinical testing of new coil developments requires animal models of aneurysms which imitate human aneurysms in size, configuration and neck morphology. We assessed in detail the technical requirements and steps for transfemoral treatment of experimentally induced aneurysms at the top of the brachiocephalic trunk (TBC) in rabbits. We created aneurysms in five rabbits by distal ligation and intraluminal incubation of the right common carotid artery with elastase. All animals were treated successfully 2-3 weeks after induction of the aneurysm, with dense packing of the coils. No complications related to the procedures occurred. The study demonstrates that our animal model can be a suitable method for testing the biocompatibility and occlusion rate of new embolic materials.  相似文献   

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Forensic Science, Medicine and Pathology - Some previously reported cases of brain evisceration in catastrophic craniocerebral injuries showed the presence of brain swelling. The aim of this study...  相似文献   

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Aim

of this study is to determine the temporal resolution of therapy-induced pneumonitis, and to assess promoting factors in adjuvant treated patients with unilateral mammacarcinoma.

Patients and methods

A total of 100 post-surgery patients were recruited. The cohort was treated by 2 field radiotherapy (2FRT; breast and chest wall, N?=?75), 3 field radiotherapy (3FRT; + supraclavicular lymphatic region, N?=?8), or with 4 field radiotherapy (4FRT; + parasternal lymphatic region, N?=?17). Ninety-one patients received various systemic treatments prior to irradiation. Following an initial screening visit post-RT, two additional visits after 12 and 25 weeks were conducted including radiographic examination. In addition, general anamnesis and the co-medication were recorded. The endpoint was reached as soon as a pneumonitis was developed or at maximum of six months post-treatment.

Results

A pneumonitis incidence of 13% was determined. Of 91 patients with prior systemic therapy, 11 patients developed pneumonitis. Smoking history and chronic obstructive pulmonary disease (COPD) appeared to be positive predictors, whereas past pneumonia clearly promoted pneumonitis. Further pneumonitis-promoting predictors are represented by the applied field extensions (2 field radiotherapy [2FRT]?<?3 field radiotherapy [3FRT]?<?4 field radiotherapy [4FRT]) and the type of combined initial systemic therapies. As a consequence, all of the three patients in the study cohort treated with 4FRT and initial chemotherapy combined with anti-hormone and antibody protocols developed pneumonitis. A combination of the hormone antagonists tamoxifen and goserelin might enhance the risk for pneumonitis. Remarkably, none of the 11 patients co-medicated with statins suffered from pneumonitis.

Conclusions

The rapidly increasing use of novel systemic therapy schedules combined with radiotherapy (RT) needs more prospective studies with larger cohorts. Our results indicate that contribution to pneumonitis occurrence of various (neo)adjuvant therapy approaches followed by RT is of minor relevance, whereas mean total lung doses of >10 Gy escalate the risk of lung tissue complications. The validity of potential inhibitors of therapy-induced pneumonitis as observed for statin co-medication should further be investigated in future trials.
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Objectives:

We investigated artefacts caused from orthodontic appliances at 1.5-T MRI of the head and neck region and whether the image quality can be improved utilizing the artefact-minimizing sequence WARP.

Methods:

In vitro tests were performed by phantom measurements of different orthodontic devices applying different types of MR sequences [echoplanar imaging (EPI), turbo spin echo (TSE) and TSE-WARP, gradient echo (GRE)]. Two independent readers determined after calibration the level of artefacts. Subsequently, the interobserver agreement was calculated. The measurement of artefacts was based on the American Society for Testing Materials Standard F 2119-07. For in vivo imaging, one test person was scanned with an inserted multibracket appliance. The level of artefacts for 27 target regions was evaluated.

Results:

In vitro: ceramic brackets and ferromagnetic steel brackets produced artefact radii up to 1.12 and 7.40 cm, respectively. WARP reduced these artefacts by an average of 32.7%. The Bland–Altman-Plot indicated that maximum measurement differences of 3 mm have to be expected with two calibrated observers. In vivo: the EPI sequence for brain imaging was not analysable. The TSE sequence of the brain did not demonstrate artefacts except for the nasal cavity. Conversely, the TSE sequence of the cervical spine revealed severe artefacts in the midface region. The GRE sequence appeared to be more susceptible to artefacts than did the TSE sequence.

Conclusions:

In vitro measurements allow an estimation of the in vivo artefact size. Orthodontic appliances may often remain intraorally when performing MRI. WARP showed a more significant effect in vitro than in vivo.  相似文献   

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The purpose of the study was to explore the possibilities of using diffusion tensor imaging (DTI) and tractography (DTT) for the differential diagnosis and monitoring of disease progression in idiopathic Parkinson’s disease (IPD), compared with the atypical parkinsonian disorders multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). A 3.0-T MR scanner was used. DTI was acquired using a single-shot EPI sequence with diffusion encoding in 32 directions and a voxel size of 2 × 2 × 2 mm3. DTI data were analysed and DTT was performed using the PRIDE fibre tracking tool supplied by the manufacturer. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) within each tract were determined. DTI and DTT images in patients with moderate to advanced MSA demonstrated degeneration of the middle cerebellar peduncles and pontine crossing tracts, with decreased FA and increased ADC. This accounted for most of the pontine and cerebellar atrophy characteristic of this disease. In contrast, patients with PSP showed a selective degeneration of the superior cerebellar peduncle. Three-dimensional images of whole-brain white matter tracts demonstrated a reduction of cortical projection fibres in all patients with PSP. Visualization of the selective degeneration of individual fibre tracts, using DTI and DTT, adds qualitative data facilitating the differential diagnosis of parkinsonian disorders. Repeated measurements of FA and ADC values in a whole fibre tract might be used for monitoring disease progression and studying the effect of treatment in neuroprotective trials. The results are preliminary considering the small number of subjects in the study.  相似文献   

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IntroductionFor patients with dementia, behaviour and reactions to stimuli can change and an X-ray examination in the hospital can have be a frightening experience. The aim of this study was to identify the experiences and perspectives of patients with dementia and their caregivers on receiving a mobile x-ray examination in nursing homes.MethodsThis study was designed as a qualitative study using patient observation and semi structured interviews, with a phenomenology-hermeneutic approach. In total, 23 patients were observed during X-ray examinations in nursing homes, and six semi structured interviews were conducted with the caregivers who participated in the examination.ResultsThe observations and interviews indicated that a known environment, a recognizable framework and calmness were central for a patient with dementia. The patients appeared calm and relaxed during the examination in their usual environment (nursing homes) where there are less stimuli and impressions based of the observations.ConclusionMobile X-ray examinations for patients with dementia living in nursing homes had a positive impact on patients' reactions towards the X-ray examination. The examinations were performed in the patients' usual and safe environments, where impressions and stimuli were less disturbing for patients with dementia.Implications for practiceThe mobile x-ray unit can be of benefit for patients suffering from dementia and result in less impact. The patients living in nursing homes have the opportunity to be examined in their familiar environment, because of the mobile x-ray unit.  相似文献   

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Little is known about the potential of artificial intelligence in forensic shotgun pattern interpretation. As shooting distance is among the main factors behind shotgun patterning, this proof-of-concept study aimed to explore the potential of neural net architectures to correctly classify shotgun pattern images in terms of shooting distance. The study material comprised a total of 106 shotgun pattern images from two discrete shooting distances (n = 54 images from 10 m and n = 52 images from 17.5 m) recorded on blank white paper. The dataset was used to train, validate and test deep learning algorithms to correctly classify images in terms of shooting distance. The open source AIDeveloper software was used for the deep learning procedure. In this dataset, a TinyResNet-based algorithm reached the highest testing accuracy of 94%. Of the testing set, the algorithm classified all 10 m patterns correctly, and misclassified one 17.5 m pattern. On the basis of these preliminary data, it seems achievable to develop algorithms that would serve as a beneficial tool for forensic investigators when estimating shooting distances from shotgun patterns. In the future, studies with larger and more complex datasets are needed to develop robust and applicable algorithms for forensic shotgun pattern interpretation.  相似文献   

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