A 64-year-old diabetic female patient presented with involuntary unilateral hyperkinetic movements of the left limbs. Cranial MRI showed a contralateral high signal intensity putaminal lesion on ...T1-weighted images without any signal changes in the T2-weighted images. This finding is characteristic for hemichorea-hemiballism associated with insufficiently treated diabetes mellitus. Additionally, proton MR spectroscopy was performed and revealed a decreased N-acetylaspartate/creatine and N-acetylaspartate/choline ratio, indicating neuronal damage of the contralateral putamen.
Evaluation of complications, patient satisfaction and clinical benefit of port systems with authorization for high pressure injection of contrast agent during CT/MR examinations.
Ultrasound-guided ...insertions of central venous port catheters were performed through the lateral subclavian vein at a university teaching hospital. The radiological information system (HIS/RIS) was used to evaluate technical success and complication rates. Assessment of patient satisfaction and clinical benefit was carried out by a questionnaire during a telephone call 6 months after implantation of the port system.
A total of 195 port systems in 193 patients were implanted. The catheter remained in place for a mean duration of 169 days (overall 29,210 catheter days). The technical success rate was 99.5 % and the overall complication rate was 17.4 % (24/138; 0.82 per 1000 catheter days). Follow-up revealed 13 early port explantations (9 %). Most of the patients reported high satisfaction in general (satisfied/very satisfied: 94 %). 34/209 contrast-enhanced CT/MRT scans (16 %) were performed using the port for contrast media injection. There were no complications during or after administration of contrast agent via the port system.
The Powerport system is a safe alternative for peripheral i. v. contrast media injection during CT/MR scans, but has been infrequently used. Most patients reported high overall satisfaction with the port system.
Clinical observations and electron microscopic investigation of skin biopsies demonstrated connective tissue abnormalities in a sizeable proportion of patients with spontaneous cervical artery ...dissection (sCAD), suggesting an unknown connective tissue disorder as a risk factor for sCAD.
To evaluate in a case-control setting if patients with sCAD exhibit clinical signs indicative of a connective tissue disorder or show a vascular phenotype.
We investigated 43 consecutive patients with sCAD and 43 consecutive patients of similar age with ischemic stroke of other etiology. All patients underwent standardized MRI of the head and neck. The clinical investigation contained 25 items characteristic for connective tissue diseases such as hyperextensible skin, articular hypermobility, capillary fragility, and facial stigmata. A sum score counting all positive items was calculated. Additionally, the diameter of the common carotid artery (CCA) and vertebral artery (VA) and heart valve pathologies were assessed.
Connective tissue sum scores did not differ between the sCAD group (mean 2.37 +/- 2.1, median 2) and the control group (mean 1.95 +/- 1.9, median 2, p = 0.34). One sCAD patient had osteogenesis imperfecta (2.3%) and exhibited the highest sum score of 8. The diameter of the CCA and VA and the prevalence of heart valve pathologies did not show any significant differences between groups.
The connective tissue and vascular phenotype did not differ significantly between patients with spontaneous cervical artery dissection (sCAD) and control subjects with ischemic stroke of other etiology. These findings argue against a clinically apparent connective tissue disorder underlying sCAD. The prevalence of known connective tissue diseases in sCAD patients is low.
This study investigates the dual-energy procedure for postoperative CT follow-up scans after endovascularly treated abdominal aortic aneurysms. The procedure is analyzed with respect to its ...sensitivity and specificity as well as the associated radiation exposure.
51 examinations were carried out on 47 patients between February 2009 and March 2010. For each patient, a non-enhanced, an arterial and a venous scan were conducted, the latter two using the dual-energy technology. Virtual images for the non-enhanced phase were reconstructed from the data taken in the venous phase. Protocol A, the reference standard, consisted of non-enhanced images and images of the arterial and venous phase. In protocol B, standard non-enhanced images were replaced by the reconstructed virtual non-enhanced images. Protocol C consisted only of virtual non-enhanced and 80 kV images taken during the venous phase. All data was anonymized and evaluated by two independent radiologists. For protocol C, sensitivity, specificity, negative and positive predictive values were computed. The effective radiation dosage was determined for each scan.
All endoleaks identified in protocol A were found using protocols B and C. For protocol C, the sensitivity and negative predictive value were 100 %, the specificity was 94.1 %, and the positive predictive value was 89.5 %. Compared to protocol A, protocol C reduces the radiation exposure by 62.45 %.
A scan protocol consisting of virtual non-enhanced images as well as 80 kV images taken during the venous phase was found to be a reliable alternative method for diagnosing endoleaks, while reducing the radiation exposure by 62.45 %.
The novel biplanar X-ray unit "EOS", EOS Imaging, allows to acquire simultaneously 2 perpendicular planes of full-length spine and limbs and to measure spatially correct angles based on the acquired ...image data sets. This is to be seen alongside with a low spatial resolution, high investment costs and high operating expenses. The use of the biplanar X-ray unit in morphology based scelettal radiography might improve the cost-benefit-relation. Thus, the purpose of this study was to compare image quality of the EOS-unit and the flat panel (FP)-technology as reference in a clinical setting.
All 114 patients of the Orthopedic Hospital Dept., who had a biplanar full-length lower limb radiograph and a FP-examination of the pelvis and/or the knee with maximum time interval of 3 months without changes in the clinical and radiological findings were included in the study. All X-ray examinations had been carried out due to clinical indications. Secondary captures comparable to the FP-images were extracted from the electronic EOS-image data sets. 4 radiologists independently from each other compared the visualization of normal anatomical structures of the pseudonymous EOS- and FP-images in a randomized order.
In the overwiew of all readers and all sceletal regions image quality of the FP-images was considered being superior in a mean of 83 ± 13 % standard deviation of the pair comparisons (minimum 48 %, maximum 100 %). Image quality of the EOS-images was assessed as being superior in 2 ± 3 % of the cases (0 %, 10 %). Image quality of 0.8 ± 3 % of the FP-images (0 %, 17 %) and 30 ± 34 % (0 %, 100 %) of the EOS-images was estimated as diagnostically inadequate. 30 ± 33 % of the pair comparisons (0 %, 100 %) showed a diagnostically inadequate image quality of the EOS-images and a diagnostically good image quality of the FP-images.
Image quality of biplanar full-length lower limb X-ray examinations is not suitable to be used for the diagnostic assessment of the morphological bone structure using the currently available technological setting.
▶ biplanar full-length lower limb X-ray examinations ▶ plat-panel radiography ▶ image quality.
Osteogenesis imperfecta (OI) is a rare hereditary disease leading to multiple bone deformities and fractures. In the absence of causal therapy, a symptomatic approach is based on treatment with ...bisphosphonates and physiotherapy. The clinical and radiological manifestations vary. Therefore, standardization and quantification for an objective comparison, especially during therapy, are required. In this paper, radiological changes of the spine are quantified according to their clinical relevance to define a scoring system that transfers the morphological changes into a single value representing the severity of the disease.
268 lateral spine X-rays of 95 patients with OI (median age 5.6 years) were assessed. The findings were classified based on their clinical relevance.
The three criteria, vertebral compression, thoracolumbar kyphosis and deformity type, were quantified in a new grading system. Based on this, a "severity classification" (1 to 5) was defined with implications for diagnostics and treatment. A mathematical formula that takes into account the three criteria and their correlations to clinical relevance, resulting in a "severity score", was developed.
"Severity classification" and "severity score" introduce a new concept for a standardized evaluation of spine X-rays in patients with OI. For both scientific and routine purposes, it provides the user with a simple and easy-to-handle tool for assessing and comparing different stages of severity prior to and during therapy with detailed accuracy.
To evaluate the feasibility of retrieval of misplaced central venous catheters in the subclavian artery with a percutaneous closure device (AngioSeal).
According to the radiologic information system ...of a university hospital, 7 patients (6 women, 1 child) underwent removal of a misplaced central venous catheter (4 × 7 F, 1 × 8 F, 2 × 13 F) in the subclavian artery between January 2008 and June 2012 with the 8 F percutaneous closure device AngioSeal. The body mass index (BMI) of 7 patients was available, 3 of whom were obese (BMI 2 × 35.7 and 1 × 33.0). Both 13 F catheters were removed in a balloon-supported manner as described elsewhere. The Broviak catheter of a 21-month-old boy was removed by surgical support with preparation of the catheter to its vessel entry. Success control was done by a transfemoral DSA in 5 of the 7 patients. 2 patients received clinical follow-up.
In all cases the misplaced catheter could be removed successfully. In all 7 patients, there was no arterial bleeding after catheter removal. Complications were not observed.
Removal of misplaced central venous catheters in the subclavian artery by the percutaneous closure device AngioSeal is safe. Percutaneous catheter removal should be regarded as the method of choice, even in obese patients.
The aim of this study was to assess the performance of a motion-map algorithm that automatically determines optimal reconstruction windows for dual-source coronary CT angiography. In datasets from 50 ...consecutive patients, optimal systolic and diastolic reconstruction windows were determined using the motion-map algorithm. For manual determination of the optimal reconstruction window, datasets were reconstructed in 5% steps throughout the RR interval. Motion artifacts were rated for each major coronary vessel using a five-point scale. Mean motion scores using the motion-map algorithm were 2.4 ± 0.8 for systolic reconstructions and 1.9 ± 0.8 for diastolic reconstructions. Using the manual approach, overall motion scores were significantly better (1.9 ± 0.5 and 1.7 ± 0.6, p < 0.05), but diagnostic image quality was reached in >90% of cases using either approach. Using the automated approach, there was a negative correlation between heart rate and motion scores for systolic reconstructions (ρ = −0.26, p < 0.05) and a positive correlation for diastolic reconstructions (ρ = 0.46, p < 0.01). For the manual approach, no significant correlation was found for systolic reconstructions (ρ = −0.1, p = 0.52), while there was a positive correlation for diastolic reconstructions (ρ = 0.48, p < 0.01). Thus, the motion-map algorithm is a useful tool to save time in finding an appropriate reconstruction window in patients with heart rates <70 bpm (diastolic reconstruction) and >80 bpm (systolic reconstruction).
Coronary magnetic resonance imaging and computed tomography are being discussed as alternatives to catheter angiography in the detection of coronary artery disease. Yet, only few comparative ...validations have been performed.
To compare steady-state free precession whole heart coronary magnetic resonance imaging (MRI) with multidetector coronary computed tomography angiography (CTA) for the detection of coronary artery disease using catheter angiography as the standard of reference.
Twenty patients with known CAD were examined with navigator (NAV) gated and corrected free-breathing 3D balanced gradient echo whole heart coronary MRI and coronary CTA. Subjective overall image quality (4 point scale, 1 = excellent), visibility of vessel segments and accuracy for the detection of significant coronary stenoses (>50%) were compared to coronary x-ray angiography by two blinded readers.
Median of subjective image quality was 3 for coronary MRI and 2 for coronary CTA. Of a total of 209 segments, 67 segments (32%) had to be excluded from the evaluation by coronary MRI (61 due to insufficient image quality and 6 due to stent artifacts). For coronary CTA, 31 segments (15%) had to be excluded from the evaluation (12 due to insufficient image quality, 15 due to severe calcifications superimposing the vessel lumen and 4 due to stent artifacts. Segment based values for the detection of >/=50% diameter coronary x-ray angiographic stenoses were: specificity: MRI 88%, CTA 95%; sensitivity: MRI 82%, CTA 84%; diagnostic accuracy: MRI 87%, CTA 93%; positive predictive value: MRI 68%, CTA 77% and negative predictive value: MRI 94%, CTA 95%.
Coronary WH-MRI was inferior to coronary CTA regarding image quality and number of evaluable segments but both had similar diagnostic value for the detection and exclusion of CAD when only evaluable segments were included.
•Spectral reconstructions facilitate subjective assessment of pancreatic lesions.•CNR is significantly higher in reconstructions highlighting iodine contrast.•HU and iodine overlaps impede ...quantitative lesion differentiation.
Dual energy CT (DECT) can contribute to the diagnosis of benign and malignant pancreatic lesions. This study examined whether a novel, detector-based spectral CT scanner (SDCT) may improve subjective assessment of different types of pancreatic lesions and if various quantitative maps may improve lesion contrast and differentiation.
61 consecutive patients who underwent clinical, contrast-agent enhanced, abdominal SDCT scans and showed pancreatic lesions of different origins were included. Subjective image analysis was performed by two readers who assessed image quality, lesion conspicuity and diagnostic confidence on 5-point Likert scales for conventional polyenergetic reconstructions (polyE), virtual monoenergetic images (monoE), virtual non-contrast images, iodine density, iodine overlay, and Z effective (Zeff) maps. Two readers acquired quantitative values from these maps ROI-based from which contrast-to-noise and lesion-to-parenchyma ratios were calculated.
MonoE images at low keV levels yielded highest Likert scores regarding lesion conspicuity and reader confidence; iodine overlays facilitated lesion delineation. Inter-observer agreement ranged between substantial and excellent (kappa values 0.73-0.81). Contrast-to-noise-ratios for low keV monoE images were significantly higher, compared to polyE images (e.g. monoE 40 keV p < 0.0001). Marked overlap between PDAC and miscellaneous non-PDAC lesions was present in various spectral reconstructions.
In line with previous studies, monoE images at low keV levels and iodine overlay maps facilitated subjective lesion delineation which was substantiated by the quantitative analysis. Hence, spectral detector CT improves pancreatic lesion conspicuity, while its value for lesion differentiation needs to be further evaluated in larger study cohorts.
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