In vitro evaluation of stent patency and in-stent stenoses in 10 metallic stents using MR angiography

In vitro study to investigate the suitability of contrast enhanced magnetic resonance angiography (CEMRA) for determination of stent patency and grading of in-stent stenoses in 10 metallic stents. The Acculink carotid, DynaLink, Easy Wallstent, JostentSelfX XF, Luminexx, Omnilink, sinus-SuperFlex, SMART, Symphony and ZA stent were separately placed in a vascular phantom. Dedicated stenoses inside the stents generated a concentric lumen narrowing of 50%. CEMRA was performed for each stent. Signal loss inside the stents and artificial lumen narrowing were assessed objectively using the evaluation software of the MR imager. Moreover, three blinded observers determined visibility of stent patency and in-stent stenoses subjectively on a 3-point scale and graded in-stent stenoses. Loss of signal intensity within the stent lumen ranged between 90% (Wallstent) and 5% (ZA), artificial lumen narrowing between 56% (Symphony) and 22% (ZA). For the Symphony and Wallstent, visibility of patency and in-stent stenoses was impaired and the observers' grading exaggerated the degree of stenoses (by 23% and 33%, respectively). For the remainder of stents, patency and stenoses were visible and stenoses were graded accurately (less than 10% discrepancy from reference standard). In this in vitro study, eight of 10 stents presented with MRI characteristics which enabled determination of stent patency and accurate grading of clinically relevant in-stent stenoses

Multidetector CT (MD-CT) in the diagnosis of uncertain open globe injuries

To evaluate the significance of multislice CT for the diagnosis of uncertain penetrating globe injuries

Use of anticoagulation during wireless capsule endoscopy for the investigation of recurrent obscure gastrointestinal bleeding

Detecting the source of obscure gastrointestinal bleeding can be difficult. Capsule endoscopy is a promising diagnostic tool for investigating patients with this condition, although identifying the source of intermittent or low-grade bleeding remains a diagnostic challenge. We present case reports of two patients with obscure gastrointestinal bleeding, in whom the source of recurrent bleeding episodes was diagnosed by capsule endoscopy while they were on anticoagulation therapy. The first patient, an 81-year-old white woman, was on long-term oral anticoagulation because she had chronic atrial fibrillation. Capsule endoscopy demonstrated a bleeding tumor in the region of the terminal ileum. The second patient, a 59-year-old white man, underwent an initial capsule endoscopy, which was negative. After initiation of anticoagulation with heparin, a second capsule endoscopy procedure in this patient revealed several small bleeding lesions in the proximal small bowel. In both cases a gastrointestinal stromal tumor was identified as the bleeding source and was resected. These two cases demonstrate that provocation of bleeding during capsule endoscopy may increase its sensitivity

Interventional Removal of Intravascular Medical Devices: Methods and Technical Success

Purpose: Evaluation of the technical success rate and complications when retrieving dislocated intravascular foreign bodies. Material and Methods: Between 1999 and 2015 38 patients (21 female; 17 male; Age: 17 -92; Average 54.3 years) underwent an extraction of intravascular dislocated foreign bodies, which were not lost during a radiological intervention. The extracted material included 29 port catheters, 3 tips of tunneled dialysis catheters, 2 stents, 2 guide wires, 1 CVC tip and 1 AS occluder device. Various catheters for repositioning and extraction were used. The access was transarterial as well as transvenous. Technical success was defined as complete removal of the foreign body. Results: The technical success rate was 92.1 % (35 of 38). In 17 patients an additional catheter was necessary to reposition the foreign body in order to make it accessible for the extraction catheter. In one case a stent was relocated and remodeled within the patient and was not extracted. In another case we experienced a dislocation of a small fragment of the port catheter into the distal parts of the pulmonary artery, which couldn't be extracted. A guide wire could not be extracted as it was already adhered with the vessel wall. Peri-interventional complications were not documented. Conclusion: The percutaneous extraction of dislocated intravascular foreign bodies is technically successful and poor of complications. Interventional therapy can avoid surgical removal. Key points: The percutaneous extraction of dislocated intravascular foreign bodies is technically successful and safe. In most cases surgical removal can be avoided. The gooseneck-snare catheter was mainly used for the extraction of intravascular foreign bodies. Citation Format: Ayx I, Goessmann H, Hubauer H et al. Interventional Removal of Intravascular Medical Devices: Methods and Technical Success. Fortschr Rontgenstr 2016; 188: 566-57

Intra-arterial MR angiography in the iliac system: initial clinical experience with 25 patients

The aim of this study was to evaluate intra-arterial magnetic resonance angiography (MRA) of the iliac arteries. Therefore, 25 consecutive patients (17 male, 8 female) suffering from symptomatic occlusive disease of the lower limbs were investigated prospectively. Catheter angiography was performed before MRA and served as the standard of reference. Contrast-enhanced intra-arterial MRA was performed using a 1.5 Tesla MRI system. Contrast agent (gadodiamide) was injected by a conventional pigtail-shaped angiography catheter placed in the abdominal aorta. Vascular lesions were assessed by four investigators. The degree of stenosis was compared with the findings of conventional catheter angiography. Additionally, the diagnostic quality of the MR angiograms was assessed by the investigators using a semi quantitative five-point scale. All lesions shown by catheter angiography were detected and correctly localized by intra-arterial MRA. MR angiograms exhibit a specificity of 95% and a sensitivity of 96% for stenoses of 50% or more. The diagnostic quality of the images was judged from good to excellent, on average. Intra-arterial MRA exhibits a specificity and sensitivity comparable with intravenous angiography. The image quality appears to be adequate for supporting MR-guided vascular intervention

[Cost analysis of contrast-enhanced cranial MRI at a German university hospital]

Detailed evaluation and cost analysis of a cranial contrast-enhanced MRI (c-ceMRI) in outpatients, inpatients, patients in an intensive care unit and children under anesthesia