共查询到20条相似文献，搜索用时 31 毫秒
1.
Purpose
Treatment of intracranial aneurysm with flow-diverting devices has become widespread in recent years. Despite that, intra-aneurysmal flow changes are yet not fully understood and can lead to different complications. Our aim was an in vitro contrast-based evaluation of the influence of flow diverter size and position on intra-aneurysmal flow dynamics.Methods
Flow-diverting devices with different sizes (diameters 4.0, 4.5, and 6.0 mm) were deployed in seven silicone aneurysm models at different positions relative to the aneurysm neck (proximal, central, distal). Using syngo iFlow, we defined quantitative evaluation criteria based on contrast medium intensity and performed a flow evaluation.Results
Intra-aneurysmal flows were heavily dependent on both size and position of flow-diverting devices at the aneurysm neck. We observed a higher peak intensity delay and intra-aneurysmal washout delay with the centrally placed 4.0- and 4.5-mm device, respectively, compared to the proximal and distal positions. Especially distally placed 4.0-mm devices led to an earlier filling of the aneurysm and increased intra-aneurysmal contrast agent intensity compared to the parent vessel, due to a potential endoleak.Conclusions
Not only size but also position of flow-diverting devices have a considerable impact on the intra-aneurysmal flow dynamics. The suggested evaluation criteria allowed a quantitative comparison of flow-diverting effect using syngo iFlow and could represent an efficient tool for predicting flow diversion pre-procedurally.2.
Ali Özgen Soner Sanioğlu Uğur Anıl Bingöl 《Cardiovascular and interventional radiology》2016,39(8):1165-1169
Purpose
To image lower extremity arteries by CT angiography using a very low-dose intra-arterial contrast medium in patients with high risk of developing contrast-induced nephropathy (CIN).Materials and Methods
Three cases with long-standing diabetes mellitus and signs of lower extremity atherosclerotic disease were evaluated by CT angiography using 0.1 ml/kg of the body weight of contrast medium given via 10-cm-long 4F introducer by puncturing the CFA. Images were evaluated by an interventional radiologist and a cardiovascular surgeon. Density values of the lower extremity arteries were also calculated. Findings in two cases were compared with digital subtraction angiography images performed for percutaneous revascularization. Blood creatinine levels were followed for possible CIN.Results
Intra-arterial CT angiography images were considered diagnostic in all patients and optimal in one patient. No patient developed CIN after intra-arterial CT angiography, while one patient developed CIN after percutaneous intervention.Conclusion
Intra-arterial CT angiography of lower extremity might be performed in selected patients with high risk of developing CIN. Our limited experience suggests that as low as of 0.1 ml/kg of the body weight of contrast medium may result in adequate diagnostic imaging.3.
Alicia S. Borggreve Anadeijda J. E. M. C. Landman Coco M. J. Vissers Charlotte D. De Jong Marnix G. E. H. Lam Evelyn M. Monninkhof Jip F. Prince 《Cardiovascular and interventional radiology》2016,39(5):696-704
Purpose
To study the effectiveness of prophylactic embolization of hepaticoenteric arteries to prevent gastrointestinal complications during radioembolization.Methods
A PubMed, Embase and Cochrane literature search was performed. We included studies assessing both a group of patients with and without embolization.Results
Our search revealed 1401 articles of which title and abstract were screened. Finally, eight studies were included investigating 1237 patients. Of these patients, 456 received embolization of one or more arteries. No difference was seen in the incidence of gastrointestinal complications in patients with prophylactic embolization of the gastroduodenal artery (GDA), right gastric artery (RGA), cystic artery (CA) or hepatic falciform artery (HFA) compared to patients without embolization. Few complications were reported when microspheres were injected distal to the origin of these arteries or when reversed flow of the GDA was present. A high risk of confounding by indication was present because of the non-randomized nature of the included studies.Conclusion
It is advisable to restrict embolization to those hepaticoenteric arteries that originate distally or close to the injection site of microspheres. There is no conclusive evidence that embolization of hepaticoenteric arteries influences the risk of complications.4.
Objectives
To assess the image quality and diagnostic accuracy of 320-row area detector CT (320-ADCT) coronary angiography using 40 mL of contrast material in comparison with 60-mL protocol.Methods
This retrospective study included 183 patients who underwent 320-ADCT coronary angiography using 40 mL of contrast and additional 183 sex- and body mass index-matched patients using 60 mL of contrast constituting the control group. Both groups used the same 5-mL/sec injection rate. Quantitative image quality measurements and diagnostic accuracies were calculated and compared.Results
Mean attenuation and contrast-to-noise ratio (CNR) at the aorta and all coronary arteries were lower in the 40-mL group than in the 60-mL group (all, p?<?0.05), except for the CNR at proximal coronary arteries at 100 kVp (p?=?0.073). However, the proportion of coronary segments with vessel attenuation >250 HU was not different between groups (all, p?>?0.05), except for distal coronary arteries at 80 kVp (p?=?0.001). Furthermore, there were no differences in per-patient and per-segment diagnostic accuracies between the groups (all, p?>?0.05).Conclusions
320-ADCT coronary angiography using 40 mL of contrast showed image quality and diagnostic accuracy comparable to the 60-mL protocol, demonstrating the clinical feasibility of lowering the risk of contrast-induced nephropathy through contrast volume reduction.Key points
? 320-ADCT might enable reduction of contrast material volume.? A 40-mL contrast protocol for 320-ADCT provided acceptable image quality.? A 40-mL contrast protocol for 320-ADCT demonstrated sufficient diagnostic accuracy.5.
Hiroyuki Morishita Yoshito Takeuchi Takaaki Ito Natsuko Hayashi Osamu Sato 《Cardiovascular and interventional radiology》2016,39(6):920-926
Purpose
The purpose of the study was to retrospectively evaluate the efficacy and safety of the balloon blocking technique (BBT).Materials and Methods
The BBT was performed in six patients (all males, mean 73.5 years) in whom superselective catheterization for transcatheter arterial embolization by the conventional microcatheter techniques had failed due to anatomical difficulty, including targeted arteries originating steeply or hooked from parent arteries. All BBT procedures were performed using Seldinger’s transfemoral method. Occlusive balloons were deployed and inflated at the distal side of the target artery branching site in the parent artery via transfemoral access. A microcatheter was delivered from a 5-F catheter via another femoral access and was advanced over the microguidewire into the target artery, under balloon blockage of advancement of the microguidewire into non-target branches. After the balloon catheter was deflated and withdrawn, optimal interventions were performed through the microcatheter.Results
After success of accessing the targeted artery by BBT, optimal interventions were accomplished in all patients with no complications other than vasovagal hypotension, which responded to nominal therapy.Conclusion
The BBT may be useful in superselective catheterization of inaccessible arteries due to anatomical difficulties.6.
Purpose
To report the 3-year results of the MAJESTIC first-in-human study of the Eluvia Drug-Eluting Vascular Stent System for treating femoropopliteal artery lesions.Methods
The prospective, single-arm, multicenter clinical trial enrolled 57 patients with symptomatic lower limb ischemia (Rutherford category 2, 3, or 4) and lesions in the superficial femoral artery or proximal popliteal artery. Mean lesion length was 70.8 ± 28.1 mm, and 46% of lesions were occluded. Efficacy measures at 2 years included primary patency, defined as duplex ultrasound peak systolic velocity ratio of ≤2.5 and the absence of target lesion revascularization (TLR) or bypass. Safety monitoring through 3 years included adverse events and TLR.Results
Primary patency was estimated as 83.5% (Kaplan–Meier analysis) at 24 months, and 90.6% (48/53) of patients maintained an improvement in Rutherford class. At 36 months, the Kaplan–Meier estimate of freedom from TLR was 85.3%. No stent fractures were identified, and no major target limb amputations occurred.Conclusion
MAJESTIC results demonstrated long-term treatment durability among patients whose femoropopliteal arteries were treated with the paclitaxel-eluting Eluvia stent.Level of Evidence
Level 2b, cohort study7.
Objectives
To prospectively evaluate the application of territorial arterial spin labelling (t-ASL) in comparison with unenhanced three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) in the identification of the feeding vasculature of meningiomas.Methods
Thirty consecutive patients with suspected meningiomas underwent conventional MR imaging, unenhanced 3D-TOF-MRA and t-ASL scanning. Four experienced neuro-radiologists assessed the feeding vessels with different techniques separately.Results
For the identification of the origin of the feeding arteries on t-ASL, the inter-observer agreement was excellent (к?=?0.913), while the inter-observer agreement of 3D-TOF-MRA was good (к?=?0.653). The inter-modality agreement between t-ASL and 3D-TOF-MRA for the feeding arteries was moderate (к?=?0.514). All 8 patients with motor or sensory disorders proved to have meningiomas supplied completely or partially by the internal carotid arteries, while all 14 patients with meningiomas supplied by the external carotid arteries or basilar arteries didn’t show any symptoms concerning motor or sensory disorders (p?=?0.003).Conclusion
T-ASL could complement unenhanced 3D-TOF-MRA and increase accuracy in the identification of the supplying arteries of meningiomas in a safe, intuitive, non-radioactive manner. The information about feeding arteries was potentially related to patients’ symptoms and pathology, making it more crucial for neurosurgeons in planning surgery as well as evaluating prognosis.Key Points
? A comprehensive understanding of feeding vasculature is helpful for optimized treatment decisions. ? T-ASL could identify main supplying arteries of meningiomas with excellent inter-observer agreement. ? The inter-modality agreement for identification of the main feeding arteries was moderate. ? Blood supply from ICAs was related to motor or sensory disorders. ? High-level meningiomas were found to have double main supplying arteries.8.
Douglas H. Sheafor Mark D. Kovacs Philip Burchett Melissa M. Picard Brenton Davis Andrew D. Hardie 《La Radiologia medica》2018,123(12):918-925
Purpose
To assess quantitative and qualitative effects of kVp on oral contrast density.Materials and Methods
Three readers retrospectively reviewed 100 CT scans performed at a range of high- and low-energy settings, independently determining their preferred window and level settings for evaluation of the oral-contrast-opacified bowel. Contrast density was also assessed quantitatively in the stomach, jejunum, and ileum. Subsequently, a range of oral contrast dilutions were imaged at varying kVp’s in a commercially available CIRS tissue equivalent phantom model.Results
In the retrospective patient study, mean oral contrast density increased significantly in the ileum compared to the jejunum (455.2 and 308.8 HU, respectively, p?<?0.01). Similar findings were seen in patients regardless of patients’ weight. Mean oral contrast density was higher on lower-energy scans, requiring more window/level adjustment. An oral contrast iodine concentration of 5.82–7.77 mg I/mL most closely approximated a target oral contrast density of 200 HU.Conclusions
Oral contrast density is strongly influenced by kVp, supporting use of more dilute oral contrast when using lower-kVp techniques.9.
Purpose
The aim of this study was to introduce a new method of producing three-dimensional (3D) images of vertebral venous plexuses (VVPs) by 3D-MRI with and without contrast media, to identify pathoanatomical features that might accelerate or modify spinal canal stenosis.Methods
We used a 1.5-T MRI unit with two different 3D sequences with and without contrast media. Multi planar reconstruction (MPR) images of VVPs could be obtained by volume image subtraction methods with a workstation for dural sac from whole 3D volume MPR without contrast media, using images before and after gadoteridol injection. Three patients with degenerative lumbar spine disease and one with cervical ossification of the posterior longitudinal ligament (OPLL) were studied with and without contrast media. As three patients underwent operations, we investigated intraoperative microscopic findings, and compared VVP images.Results
Abundant components of internal VVPs were identified on MRI in correlation with neural tissues such as dura and nerve roots.Conclusions
Using 3D MRI without and with gadoteridol, we can evaluate morphological changes in VVP under degenerative spinal conditions. The MR anatomy of VVPs of the spine is important, as it has been implicated in many pathophysiological mechanisms and may also cause pitfalls in MRI.10.
D. Gümbel F. Schneidler M. Frank B. Bockholdt M. Napp A. Ekkernkamp S. Langner 《Rechtsmedizin》2016,26(3):218-223
Background
Determination of the urinary bladder volume (UBV) is an essential part of autopsy examinations and can provide important information on the cause of death. Manual three-dimensional computed tomography (3D-CT) volumetry enables the UBV to be calculated without external manipulation.Objective
The purpose of this study was to analyze the accuracy of the radiological measurement of UBV by 3D-CT volumetry compared to sonography in a phantom model.Material and methods
A total of 11 phantom bodies were prepared with different volumes. In order to simulate pressure on the bladder wall by adjacent structures, compression was applied from the outside by means of a wire mesh and three different degrees of pressure were applied to mimic conditions in vivo. After CT examination 3D-CT volumetry and calculation of the phantom volume using a widely accepted ultrasonographic formula were carried out. The statistical analysis was performed using the Wilcoxon test for paired samples.Results
The average real volume of the phantom objects was 704.7 ml. The average volume measured using the 3D-CT calculation was 656.8 ml and 555.0 ml using the sonographic formula. There was a significantly higher accuracy for the 3D volumetry (6.8?±?2.3?%) in comparison to the sonographic formula (21.2?±?7.9?%) in relation to the real volumes of the phantom. The accuracy of the UBV calculation was higher for 3D-CT volumetry compared to the sonographic formula for all degrees of pressure.Conclusion
The use of 3D-CT volumetry with a detailed depiction of the sectional planes and high resolution allows accurate 3-dimensional reconstruction of the UBV regardless of the degree of complexity. By implementation of 3D-CT volumetry, e.g. during autopsy, an accurate determination of the UBV is possible.11.
Clinical/methodical issue
Entrapment syndromes of peripheral nerves at the elbow are common and are often diagnostically challenging disorders. Difficulties consist in lesion localization and recognition of complex spatial lesion patterns as well as in differentiation of focal and multifocal disorders.Standard diagnostic methods
Medical history taking, neurological examination and neurophysiological tests represent the gold standard in the diagnosis of peripheral nerve lesions at the elbow, but have known methodical limitations.Methodical innovations
Additional diagnostic imaging tools recently developed for high-resolution visualization of extended peripheral nerve segments include 3?T magnetic resonance neurography (MRN) and neurosonography.Performance
MRN and neurosonography can directly visualize and thus precisely localize focal and nonfocal peripheral nerve lesions of various origins with high spatial resolution at the anatomical level of nerve fascicles.Achievements
MRN can cover peripheral nerve structures at the elbow, evaluate spatial nerve lesion patterns and partly disclose underlying causes.Practical recommendations
Imaging of peripheral nerves is a valuable addition in the diagnostic work-up of entrapment syndromes at the elbow and provides important assistance in the differentiation of nonfocal differential diagnoses, especially in cases that cannot be clarified using standard diagnostic methods. The evaluation of spatial nerve lesion pattern may give additional information on the origin of the underlying disease, which is essential for further treatment.12.
K. Müller-Peltzer G. Negrão de Figueiredo V. Schwarze J. Rübenthaler D. A. Clevert 《Der Radiologe》2018,58(10):887-893
Clinical/methodical issue
Cystic renal lesions are commonly seen during routine ultrasound examinations of the abdomen.Standard radiological methods
Some cystic renal lesions cannot be sufficiently characterized using native ultrasound. In these cases additional imaging might be necessary.Methodical innovations
Contrast-enhanced ultrasound (CEUS) is a reliable imaging modality to characterize cystic renal lesions. Contrast enhancement of septations and the cystic wall are visualized in high resolution. This information helps to categorize the cystic renal lesions applying the CEUS Bosniak classification. This classification helps to estimate the probability of a malignant etiology of cystic renal lesions.Performance
Using CEUS, cystic renal lesions can be characterized with a high sensitivity and specificity.Achievements
The advantages of CEUS include that there is no effect on the function of the kidneys or the thyroid gland and no radiation exposure. In some cases, additional cross-sectional imaging is necessary to optimize diagnostic accuracy.Practical recommendations
CEUS is a helpful imaging modality to characterize cystic renal lesions, to avoid unnecessary follow-ups and to detect malignant cystic renal lesions.13.
14.
Purpose
There is no golden standard management for neglected, chronic patellar tendon rupture as they are fairly rare. Nevertheless, accompanying pain can be highly debilitating. By presenting a case of patellar tendon repair, the exceptional results of a patellofemoral arthrodesis are described.Methods
A patient presented herself with a sustained patellar tendon rupture which was neglected for several years, causing a complete extensor mechanism dysfunction. Her most debilitating complaint was pain. As ligament reconstruction in this case was not possible, patellofemoral arthrodesis was aimed for. The pain resulting from micromotions was subsided by implementing a unique technique using a lock-key principle to obtain a patellofemoral arthrodesis.Results
The procedure proceeded without complications. The patient followed a regular post-operative plan and is now successful in maximum weight bearing her knee without pain.Conclusions
A patellofemoral arthrodesis can be regarded safe and also very effective in the relief of pain in extreme patella alta.Level of evidence
Therapeutic studies, Level IV.15.
Kaan Esen Anil Ozgur Yuksel Balci Sermin Tok Engin Kara 《Japanese journal of radiology》2018,36(2):96-102
Objective
To investigate the anatomical variations in the origins of the thyroid arteries on CT angiography images.Methods
The presence and the origins of the superior thyroid artery, the inferior thyroid artery, and the thyroidea ima artery were retrospectively evaluated based on carotid CT angiography examinations. The bifurcation level of the common carotid artery with respect to the cervical vertebrae and disc spaces was also determined. A total of 640 patients were included in the study.Results
The right and left superior thyroid arteries arose from the external carotid artery in 413 (64.5%) and 254 (39.7%) patients, from the bifurcation of the common carotid artery in 131 (20.5%) and 148 (23.1%) patients, and from the common carotid artery in 90 (14.1%) and 226 (35.3%) patients, respectively. We could not observe the right and the left superior thyroid arteries in 6 (0.9%) and 12 (1.9%) of the patients, respectively. However, the right and left inferior thyroid arteries were not identified in 14 (2.2%) and 45 (7%) of the patients, respectively. The thyroidea ima artery was detected in 2.3% of the patients.Conclusion
The visualization of thyroid arteries on CT angiography images enables the anatomy of the arterial supply system of the thyroid gland to be explored in a noninvasive manner prior to surgery.16.
Objectives
MR venography (MRV) protocols have used bloodpool contrast agents and long scan sequences to identify patients suitable for treatment and preoperatively. However, variable availability of bloodpool contrast agents, high costs and a need to shorten acquisition times for routine MR protocols hamper everyday practice.Materials
20 patients (11 men; mean age 54?±?11.8 years; body mass index 23.6?±?2.5) were enrolled in this prospective study. An intra-individual comparison of image quality, interpretation and findings for two different contrast agents (regular gadolinium contrast agent gadobutrol vs. bloodpool contrast agent gadofosveset-trisodium) and two different scan protocols (long acquisition time protocol using a high-resolution fast field echo (FFE) sequence vs. short acquisition time protocol using an ultra-fast gradient echo (GE) sequence) were performed.Results
Image quality (average of 4.94 vs. 4.92 on a five-point scale), interpretation and contrast-to-noise ratio (44 vs. 45) were equal for both contrast agents. Image findings showed no statistical significant differences between the MR protocols or contrast agents (overall p?=?0.328).Conclusions
For high-resolution MRV, it is possible to replace gadofosveset-trisodium with gadobutrol. Furthermore, an ultra-fast GE sequence for MRV might considerably shorten acquisition time, without loss of image quality or diagnostic yield.Key Points
? High-quality MRV can be performed with a regular gadolinium-based contrast agent.? Ultra-fast GRE vs. HR-FFE MRV: equally suitable for evaluation of venous obstruction.? Regular gadolinium-based contrast agent can supersede a bloodpool contrast agent for MRV.? Equal confidence for gadobutrol vs gadofosveset-trisodium in MRV.? MRV accessible for routine daily practice.17.
Gabriel Chan Lawrence Hwee Han Quek Glenn Leong Wei Tan Uei Pua 《Cardiovascular and interventional radiology》2016,39(7):1036-1039
Background
Insertion of a carotid chimney graft during thoracic endovascular aortic repair (Ch-TEVAR) is a recognized technique to extend the proximal landing zone into the aortic arch in the treatment of thoracic aortic disease. Conventional technique requires surgical exposure of the carotid artery for insertion of the carotid chimney graft.Methodology
We describe our experience in the use of a suture-mediated closure device in percutaneous Ch-TEVAR in four patients.Results
Successful hemostasis was achieved in all four patients. No complications related to the carotid puncture were recorded.Conclusion
We conclude that using suture-mediated closure device for carotid closure appears feasible and deserves further studies as a potential alternative to conventional surgical approach.18.
Motoo Nakagawa Yoshiyuki Ozawa Norikazu Nomura Sachiko Inukai Ayano Shiba Keita Sakurai Masashi Shimohira Yuta Shibamoto 《Japanese journal of radiology》2018,36(3):215-222
Purpose
Children with congenital heart diseases (CHDs) may need to be followed up with contrast-enhanced CT following the Fontan operation because complications such as the occlusion of conduits may occur. The purpose of the present study was to develop an adequate contrast-enhanced CT protocol for children with CHD following the Fontan operation.Materials and methods
Between July 2012 and July 2017, 29 CT examinations for 26 patients aged 2–11 years (median 5 years) with CHD following the Fontan operation were performed using dual-source CT. A non-ionized contrast medium was injected through the dorsum manus vein. Scanning began 60 or 70 s after the start of the injection. The delayed phase was randomly selected to be 60 s in 14 cases and 70 s in 15 cases. We evaluated the enhancement of conduits following the Fontan operation at delayed phases.Results
The CT numbers of conduits at 60 and 70 s were 185 ± 46 and 185 ± 31 HU, respectively (P = 0.97).Conclusion
In contrast-enhanced CT for children after the Fontan operation, both of the delayed phases (60 and 70 s) appeared to be adequate for evaluating intraconduit patency.19.
Abram W. Makram Ayman M. Khalifa Hossam El-Rewaidy Ahmed S. Fahmy El-Sayed H. Ibrahim 《Japanese journal of radiology》2016,34(2):158-165
Purpose
Tagged and cine magnetic resonance imaging (tMRI and cMRI) techniques are used for evaluating regional and global heart function, respectively. Measuring global function parameters directly from tMRI is challenging due to the obstruction of the anatomical structure by the tagging pattern. The purpose of this study was to develop a method for processing the tMRI images to improve the myocardium-blood contrast in order to estimate global function parameters from the processed images.Materials and methods
The developed method consists of two stages: (1) removing the tagging pattern based on analyzing and modeling the signal distribution in the image’s k-space, and (2) enhancing the blood-myocardium contrast based on analyzing the signal intensity variability in the two tissues. The developed method is implemented on images from twelve human subjects.Results
Ventricular mass measured with the developed method showed good agreement with that measured from gold-standard cMRI images. Further, preliminary results on measuring ventricular volume using the developed method are presented.Conclusion
The promising results in this study show the potential of the developed method for evaluating both regional and global heart function from a single set of tMRI images, with associated reduction in scan time and patient discomfort.20.