A simple classification system (the Tree flowchart) for breast MRI can reduce the number of unnecessary biopsies in MRI-only lesions.

OBJECTIVES: To assess whether using the Tree flowchart obviates unnecessary magnetic resonance imaging (MRI)-guided biopsies in breast lesions only visible on MRI. METHODS: This retrospective IRB-approved study evaluated consecutive suspicious (BI-RADS 4) breast lesions only visible on MRI that were referred to our institution for MRI-guided biopsy. All lesions were evaluated according to the Tree flowchart for breast MRI by experienced readers. The Tree flowchart is a decision rule that assigns levels of suspicion to specific combinations of diagnostic criteria. Receiver operating characteristic (ROC) curve analysis was used to evaluate diagnostic accuracy. To assess reproducibility by kappa statistics, a second reader rated a subset of 82 patients. RESULTS: There were 454 patients with 469 histopathologically verified lesions included (98 malignant, 371 benign lesions). The area under the curve (AUC) of the Tree flowchart was 0.873 (95% CI: 0.839-0.901). The inter-reader agreement was almost perfect (kappa: 0.944; 95% CI 0.889-0.998). ROC analysis revealed exclusively benign lesions if the Tree node was ≤2, potentially avoiding unnecessary biopsies in 103 cases (27.8%). CONCLUSIONS: Using the Tree flowchart in breast lesions only visible on MRI, more than 25% of biopsies could be avoided without missing any breast cancer. KEY POINTS: • The Tree flowchart may obviate >25% of unnecessary MRI-guided breast biopsies. • This decrease in MRI-guided biopsies does not cause any false-negative cases. • The Tree flowchart predicts 30.6% of malignancies with >98% specificity. • The Tree's high specificity aids in decision-making after benign biopsy results.

Effect of ß-blocker on aneurysm sac behavior after endovascular abdominal aortic repair.

OBJECTIVE: This study was conducted to determine whether ß-blocker (BB) therapy is associated with abdominal aortic aneurysm (AAA) sac regression after endovascular abdominal aortic repair (EVAR). METHODS: A total of 198 patients (mean age, 76 years) who underwent EVAR were analyzed (104 in the BB group and 94 in the non-BB group). The primary end point was the incidence of AAA sac regression at 1 and 2 years. RESULTS: Hypertension, coronary artery disease, and hyperlipidemia were more common in the BB group. The BB group was also more likely to have been prescribed an aspirin and a statin than the non-BB group. The length of proximal neck was significantly longer in the non-BB group than in the BB group. All study patients were monitored for at least 1 year after EVAR, and 2-year follow-up was available in 104 patients (52.5%). There was no statistically significant difference in the incidence of aneurysm sac regression in either group at 1 year (52.1% in the non-BB group vs 45.2% in the BB group; P = .330) and 2 years (58.5% in the non-BB group vs 64.7% in the BB group; P = .515). The difference of the change of AAA maximum diameter between two groups did not reach statistical significance at 1 year (-6.0 ± 7.0 mm in the non-BB group vs -5.5 ± 8.1 mm in the BB group; P = .644) and 2 years (-9.0 ± 10.5 mm in the non-BB group vs -9.0 ± 10.0 mm in the BB group; P = .977). BB therapy was not associated with increased odds of AAA sac regression. The effect of third-generation BBs on AAA sac regression was not significant. CONCLUSIONS: BB therapy had no effect on AAA sac regression. At the present time, there is insufficient evidence to recommend BB therapy for the purpose of AAA sac regression.

Influence of Statin Therapy on Aneurysm Sac Regression after Endovascular Aortic Repair.

PURPOSE: To determine whether statin therapy is associated with abdominal aortic aneurysm (AAA) sac regression after endovascular aneurysm repair (EVAR). MATERIALS AND METHODS: A total of 109 patients treated with EVAR were retrospectively analyzed (no-statin group, n = 45; statin group, n = 64). The primary endpoint was the incidence of AAA sac regression. To investigate independent predictors of AAA sac regression, regression analysis was performed. The mean age was 74 years (range, 55-90 y), and 87.2% of patients were men. RESULTS: The no-statin group had higher rates of AAA sac regression than the statin group at 1 year (no-statin group, 66.7%; statin group, 45.3%; P = .028). The incidence of AAA sac regression increased over time in the statin group, and no statistical difference was seen between the two groups at 2 years (no-statin group, 66.7%; statin group, 57.8%; P = .350). The difference between the changes in maximum AAA diameter was significant between groups at 1 year (no-statin group vs statin group, -4.9 mm ± 5.9; P = .041), but the difference did not reach statistical significance at 2 years (no-statin group, -10.0 mm ± 10.1; statin group, -8.0 mm ± 9.6; P = .306). Statin therapy was not associated with AAA sac regression on univariate (odds ratio [OR], 0.685; 95% confidence interval [CI], 0.310-1.516; P = .351) and multivariate analyses (OR, 0.617; 95% CI, 0.215-1.772; P = .369). CONCLUSIONS: Statin therapy had no effect on AAA sac regression at 2 years. There is insufficient evidence to recommend statin therapy for AAA sac regression.

Effects of Percutaneous Transluminal Angioplasty on Diastolic Function in Patients With Chronic Occlusion of Lower-Extremity Artery.

OBJECTIVE: We investigated whether successful revascularization of total occlusion of a large lower-extremity artery is associated with improvement of left ventricular (LV) diastolic function. BACKGROUND: Total occlusion of a large lower-extremity artery might affect the systemic vascular resistance and increase the afterload, because the left ventricle must work harder to eject blood into a smaller vascular bed. Chronic elevation of afterload is a cause of LV diastolic dysfunction. METHODS: This is a single-center retrospective analysis of 20 patients (10 men, age 69.6 ± 12.3 years) with chronic total occlusions (CTOs) of the aorto-iliac and femoropopliteal segments who underwent a successful endovascular revascularization. Baseline and postprocedural evaluation of diastolic function was performed, and the primary endpoint was improvement in LV diastolic function, which was defined as any decrease of the baseline E/E' ratio or any increase of the baseline E' velocity after the index procedure. RESULTS: There was a significant effect of successful revascularization on the E/A ratio (from 1.5 ± 1.1 to 1.0 ± 0.3; P=.046) because of a significant increase of A velocity (from 86.3 ± 30.4 cm/s to 98.3 ± 21.8 cm/s; P=.03). The E' velocity (from 7.4 ± 2.0 cm/s to 8.3 ± 2.3 cm/s; P=.07) did not show a significant increase, but there was a significant reduction in E/E' ratio (from 14.6 ± 3.9 to 12.4 ± 3.3; P=.02). Logistic regression analysis did not identify possible predictors of improvement in LV diastolic function. CONCLUSION: Our results showed that a successful revascularization was associated with improvement in the echocardiographic parameters of LV diastolic function in patients with CTO of large lower-extremity artery, and these changes may be related to the afterload reduction.

The Influence of Statin Therapy on Restenosis in Patients Who Underwent Nitinol Stent Implantation for de Novo Femoropopliteal Artery Disease: Two-Year Follow-up at a Single Center.

PURPOSE: To determine whether statin therapy is associated with reduced restenosis following nitinol stent implantation for de novo femoropopliteal artery disease. MATERIALS AND METHODS: A total of 135 limbs in 135 patients (mean age, 72 y) implanted with nitinol stents in femoropopliteal occlusions were analyzed (statin arm, n = 91; nonstatin arm, n = 44). The patients were treated with one type of nitinol stent. RESULTS: At baseline, lesions and procedural characteristics were comparable between groups, except that the statin group had more hypertension, coronary artery disease, and hyperlipidemia. There were significant differences in the incidence of binary restenosis between groups at 1 year (45.5% for nonstatin group vs 28.6% for statin group; P = .05) and 2 years (56.8% for nonstatin group vs 38.5% for statin group; P = .04). Primary patency rates at 1 year were 50.5% in the nonstatin group and 72.5% in the statin group (P = .01). Two-year target lesion revascularization rates were 54.5% in the nonstatin group and 35.2% in the statin group (P = .03). On univariate analysis, statin therapy was associated with decreased relative risk of binary restenosis at 1 year (odds ratio [OR], 0.480; 95% confidence interval [CI], 0.227-1.014; P = .050). On multivariate analysis, statin therapy did not significantly affect the odds of binary restenosis (OR, 0.415; 95% CI, 0.071-2.437; P = .330). CONCLUSIONS: The incidence of binary restenosis was significantly lower in the statin group than in the nonstatin group following nitinol stent implantation for de novo femoropopliteal artery disease.

Degeneration and Instability and the Relation to Patients' Function Late After Lumbar Disc Surgery: Data from a 12-Year Follow-Up.

OBJECTIVE: To investigate the excess risk of degeneration and segmental instability in operated segments late after lumbar disc surgery in patients with presurgically stable segments, and whether local pathological findings relate to patients' back health. DESIGN: This retrospective analysis reports on 69 patients 12 years after first-time, uncomplicated lumbar disc surgery. Two independent radiologists evaluated the patients' lumbar functional x-rays; the Back Pain Rating Score (LBP-RS) assessed back-specific function. RESULTS: At 12 years after lumbar disc surgery, degenerative changes as well as segmental instability occurred significantly more frequently in the operated than nonoperated lumbar segments, but there was no association between increased degeneration and segmental instability rates. The risk for acquiring segmental instability was significantly associated with surgery (odds ratio, 6.5; 95% confidence interval, 1.5-28.8). Prevalence of segmental instabilities was associated with better LBP-RS scores. Analyses of LBP-RS subscores revealed a clear association of segmental instability with physical function, but not with pain or activities of daily living. CONCLUSIONS: Lumbar disc surgery seems to be associated with an increased risk of degeneration and segmental instability in the long term. This structural impairment, however, seems functionally well compensated and does not seem to be a relevant causal factor for a chronic back pain syndrome. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES:: Upon completion of this article, the reader should be able to: (1) Describe the impact of lumbar disc surgery on segmental instability and degenerative changes; (2) Recognize the lack of association between degenerative changes and segmental instability after lumbar disc surgery; and (3) State the value of lumbar spinal functional tests in the evaluation of patients after lumbar disc surgery. LEVEL: Advanced ACCREDITATION:: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The Association of Academic Physiatrists designates this activity for a maximum of 1.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

MR-guided vacuum-assisted breast biopsy of MRI-only lesions: a single center experience.

PURPOSE: The purpose of this study was to compare three different biopsy devices on false-negative and underestimation rates in MR-guided, vacuum-assisted breast biopsy (VABB) of MRI-only lesions. METHODS: This retrospective, single-center study was IRB-approved. Informed consent was waived. 467 consecutive patients underwent 487 MR-guided VABB using three different 8-10-gauge-VABB devices (Atec-9-gauge,A; Mammotome-8-gauge,M; Vacora-10-gauge,V). VABB data (lesion-type, size, biopsy device, histopathology) were compared to final diagnosis (surgery, n = 210 and follow-up, n = 277). Chi-square, and Kruskal-Wallis tests were applied. P values < 0.05 were considered significant. RESULTS: Final diagnosis was malignant in 104 (21.4 %), high risk in 64 (13.1 %) and benign in 319 (65.5 %) cases. Eleven of 328 (3.4 %) benign-rated lesions were false-negative (1/95, 1.1 %, A; 2/73, 2.7 %, M; 8/160 5.0 % V; P = 0.095). Eleven high-risk (11/77, 14.3 %) lesions proved to be malignant (3/26, 11.5 % A; 4/12, 33.3 % M; 4/39, 10.3 % V; P = 0.228). Five of 34 (14.7 %) DCIS were upgraded to invasive cancer (2/15, 13.3 %, A; 1/6, 16.6 % M; 2/13, 15.3 %, V; P = 0.977). Lesion size (P = 0.05) and type (mass vs. non-mass, P = 0.107) did not differ significantly. CONCLUSION: MR-guided VABB is an accurate method for diagnosis of MRI-only lesions. No significant differences on false-negative and underestimation rates were observed between three different biopsy devices. KEY POINTS: • MR-guided VABB is an accurate procedure for the diagnosis of MRI-only lesions. • Similar false-negative and underestimation rates allow all three different MR-guided VABB devices for clinical application. • High-risk lesions should undergo surgery due to a substantial underestimation rate. • Agreement between MR-guided VABB and final diagnosis (benign/malignant) was 95.5% (465/487).

Endovascular Treatment of Inflammatory Infrarenal Aortic Aneurysms.

OBJECTIVES: The aim of this study was to evaluate short- and midterm outcomes of endovascular aneurysm repair in patients with inflammatory abdominal aortic aneurysm (IAAA) focusing on changes in perianeurysmal inflammation and hydronephrosis. METHODS: A retrospective study was performed considering data prospectively gathered from 1998 to 2013 in 3 centers. Patient demographics, preoperative clinical characteristics, clinical presentation, preoperative imaging measurements, procedural, and postoperative data were collected. Main outcome was to define evolution of periaortic fibrosis and hydronephrosis at computed tomography angiography (CTA) during follow-up. RESULTS: A total of 22 patients (male n = 20; mean age 70.9 years ± 9.3) were included (mean AAA diameter: 58 mm ± 11, symptomatic: 50%, ruptured: 9.1%). Hydroureteronephrosis was preoperatively diagnosed by CTA in 6 (27.3%) cases. Median clinical follow-up was 2.2 years (range 0.1-14.5). Nine patients died during follow-up. At 1, 2, 4, and 6 years, overall survival was 85.4%, 74.3%, 56.6%, and 49.5%, respectively. Among these 13 patients with CTA follow-up, the mean AAA diameter was 56.2 mm ± 15.5, and progression of sac diameter was detected in 1 (7.7%) patient. Median maximum thickness of perianeurysmal inflammation was 5 mm (range 2-11) and decreased/remained unchanged in 92.3% of patients. Regression of hydroureteronephrosis occurred in 3 of 5 patients available for follow-up. There were no cases of de novo hydroureteronephrosis. CONCLUSION: Endovascular treatment of IAAA has comparable short-term outcomes with non-IAAA. During midterm follow-up, aneurysm sac progression is rare, and perianeurysmal fibrosis decreases or remains unchanged in most cases. Hydronephrosis regression can occur in some but not all instances and thus warrants close surveillance.

Radioprotective lightweight caps in the interventional cardiology setting: a randomised controlled trial (PROTECT).

AIMS: The aim of this study was to test the radioprotection efficacy and comfort of newer bilayer barium sulphate-bismuth oxide composite (XPF) caps in an interventional cardiology setting. METHODS AND RESULTS: Operators were randomly assigned to wear standard fabric (n=59), 0.3 mm (n=74), or 0.5 mm (n=64) lead-equivalent XPF caps. Radiation doses were measured by using dosimeters placed outside and underneath the caps. Wearing comfort was assessed at the end of each measurement on a visual analogue scale (VAS) (0-100, with 100 indicating optimal comfort). Procedural data did not differ between the XPF and standard groups. Mean standard, XPF 0.3 mm, and XPF 0.5 mm cap weights were 12.5 g, 118.4 g, and 123.7 g, respectively. VAS comfort ratings of the standard and XPF caps did not differ significantly (p=0.272). The mean radiation protection was 12.0%, 95% CI: 4.9-19.1% (standard caps, n=35), 91.5%, 95% CI: 87.4-95.6% (XPF 0.3 mm caps, n=45) and 97.1%, 95% CI: 92.5-100% (XPF 0.5 mm caps, n=44) (p≤0.001 for all group comparisons). Using the XPF caps, a cumulative total radiation dose reduction by almost factor 10 was evident (272 procedures, 22,310 µSv outside the XPF caps, 2,770 µSv inside the caps). CONCLUSIONS: Lightweight XPF caps show comparable comfort to standard fabric caps, but provide substantial radiation protection during fluoroscopy-guided cardiac interventions.

Reliability and accuracy of simple visual estimation in assessment of peripheral arterial stenosis.

PURPOSE: To evaluate reliability, accuracy, and agreement of simple visual estimation (SVE) in determining the degree of peripheral arterial stenosis compared with calibrated measurements. MATERIALS AND METHODS: In 2 sessions, 23 interventionists with a wide range of experience and subspecialty training reviewed 42 angiographic images of lower extremity and carotid arteries (21 iliofemoral arteries and 21 carotid arteries). An independent physician measured all lesions using manual calipers. Intrarater and interrater reliability were assessed by intraclass correlation. A ± 5% error was considered the threshold for accuracy, and weighted κ statistics were computed to assess agreement with respect to the degree of stenosis (< 50%, nonsignificant; 50%-80%, significant; > 80%, severe). RESULTS: Intrarater reliability of SVE was 0.99, and interrater reliability was 0.83. Accuracy varied from 52.8% for images of severe stenosis to 26.5% and 18.1% for significant and nonsignificant stenosis, respectively (P < .001). Agreement between SVE and caliper with regard to degree of stenosis was good (weighted κ 0.56) overall with correct classification ranging from 92.6% for severe stenosis to 53.4% and 68.2% for significant and nonsignificant stenosis, respectively (P < .001). Misclassification of nonsignificant and significant stenosis was more frequent for carotid arteries than for lower extremities. CONCLUSIONS: Despite high reliability, SVE of peripheral arterial stenosis has limited accuracy in determining the exact degree of stenosis. Although severe stenosis is readily identified by SVE, arterial stenosis of < 80% is frequently overestimated, especially for carotid arteries, and should be confirmed by caliper assessment.

Veins in plaques of multiple sclerosis patients - a longitudinal magnetic resonance imaging study at 7 Tesla.

OBJECTIVE: To monitor the venous volumes in plaques of patients with multiple sclerosis (MS) compared to an age-matched control group over a period of 3.5 years. METHODS: Ten MS patients underwent an annual neurological examination and MRI. Susceptibility-weighted imaging (SWI) combined with fluid-attenuated inversion recovery (FLAIR) or FLAIR-like contrast at 7 Tesla (7 T) magnetic resonance imaging (MRI) was used for manual segmentation of veins in plaques, in the normal-appearing white matter (NAWM) and in location-matched white matter of 9 age-matched controls. Venous volume to tissue volume ratio was assessed for each time point in order to describe the dynamics of venous volumes in MS plaques over time. RESULTS: MS plaques, which were newly detected during the study period, showed significantly higher venous volumes compared to the preplaque area 1 year before plaque detection and the corresponding NAWM regions. Venous volumes in established MS plaques, which were present already in the first scans, were significantly higher compared to the NAWM and controls. CONCLUSIONS: Our data underpin a relation of veins and plaque development in MS and reflect increased apparent venous calibers due to increased venous diameters or increased oxygen consumption in early MS plaques. KEY POINTS: • Longitudinal 7 T Magnetic Resonance Imaging study of intralesional veins in MS patients. • Venous volumes are significantly increased in newly detected and established MS plaques. • Venous volumes in established MS plaques show a trend to decrease with time.

Ultrasound-accelerated versus standard catheter-directed thrombolysis in 102 patients with acute and subacute limb ischemia.

PURPOSE: To compare the safety and efficacy of ultrasound-accelerated thrombolysis (UAT) and standard catheter-directed thrombolysis (CDT) in patients with acute and subacute limb ischemia. MATERIALS AND METHODS: Medical records of all patients treated with thrombolysis for acute and subacute limb ischemia between August 2005 and January 2012 were reviewed. Coprimary (increase in ankle-brachial index, degree of lysis) and secondary endpoints (technical success, distal embolization, bleeding complications, need for additional interventions) were assessed. UAT was performed in 75 patients, and CDT was performed in 27 patients. Patients' baseline demographic and clinical parameters and procedure details, including lytic drug infusion rate (P = .704 and P = .987), total infusion time (P = .787 and P = .377), and use of adjunctive procedures (P = .457), did not differ significantly between the two groups. RESULTS: Complete lysis was achieved in 72.0% (UAT) and 63.0% (CDT) of patients (P = .542); hemodynamic success was achieved in 91.8% (UAT) and 92.3% (CDT) (P = .956). Overall major and minor bleeding complications were observed in 6.9% (UAT) and 3.9% (CDT) of patients. Major (P = .075) and minor (P = .276) bleeding independently did not differ between UAT and CDT. Major and minor bleeding combined was lower: 6.7% (UAT) versus 22.2% (CDT) (P = .025). Overall target vessel patency after 8.0 months (range, 1.5-20.5 mo) was 73.5%; target vessel patency for UAT was 75.9% versus 64.3% for CDT (P = .379). Median long-term survival was not significantly different between UAT and CDT: 3.6 years (range, 2.42-5.33 y) versus 1.8 years (range, 1.33-4.92 y) (P = .061). CONCLUSIONS: Both UAT and CDT are safe and efficient treatment modalities for patients with acute and subacute limb ischemia. The observed lower risk of total bleeding for UAT versus CDT may warrant prospective comparative trials.

Lightweight bilayer barium sulfate-bismuth oxide composite thyroid collars for superior radiation protection in fluoroscopy-guided interventions: a prospective randomized controlled trial.

PURPOSE: To test whether newer bilayer barium sulfate-bismuth oxide composite (XPF) thyroid collars (TCs) provide superior radiation protection and comfort during fluoroscopy-guided interventions compared with standard 0.5-mm lead-equivalent TCs. MATERIALS AND METHODS: Institutional review board approval and written informed consent were obtained for this HIPAA-compliant study, and 144 fluoroscopy-guided vascular interventions were included at one center between October 2011 and July 2012, with up to two operators randomly assigned to wear XPF (n = 135) or standard 0.5-mm lead-equivalent (n = 121) TCs. Radiation doses were measured by using dosimeters placed outside and underneath the TCs. Wearing comfort was assessed at the end of each procedure on a visual analog scale (0-100, with 100 indicating optimal comfort). Adjusted differences in comfort and radiation dose reductions were calculated by using a mixed logistic regression model and the common method of inverse variance weighting, respectively. RESULTS: Patient (height, weight, and body mass index) and procedure (type and duration of intervention, operator, fluoroscopy time, dose-area product, and air kerma) data did not differ between the XPF and standard groups. Comfort was assessed in all 256 measurements. On average, the XPF TCs were 47.6% lighter than the standard TCs (mean weight ± standard deviation, 133 g ± 14 vs 254 g ± 44; P < .001) and had a significantly higher likelihood of a high level of comfort (visual analog scale >90; odds ratio, 7.6; 95% confidence interval: 3.0, 19.2; P < .001). Radiation dose reduction provided by the TCs was analyzed in 117 data sets (60 in the XPF group, 57 in the standard group). The mean radiation dose reductions (ie, radiation protection) provided by XPF and standard TCs were 90.7% and 72.4%, with an adjusted mean difference of 17.9% (95% confidence interval: 7.7%, 28.1%; P < .001) favoring XPF. CONCLUSION: XPF TCs are a lightweight alternative to standard 0.5-mm lead-equivalent TCs and provide superior radiation protection during fluoroscopy-guided interventions.

Prospective comparison of palpation versus ultrasound-guided radial access for cardiac catheterization.

BACKGROUND: Radial access is increasingly used for both diagnostic and interventional cardiac procedures. Prospective data comparing ultrasound- versus palpation-guided radial catheterization are largely lacking. METHODS: In this prospective, single-center study, a total of 183 consecutive patients scheduled for transradial cardiac catheterization by an experienced interventionalist were assigned 1:1 to either palpation- or ultrasound-guided radial access. Demographic and procedure parameters were prospectively recorded. RESULTS: Baseline demographic and clinical parameters did not differ significantly between the ultrasound group (n = 92) and palpation group (n = 91). The initial radial catheterization success rate (87% vs 86.8%; P=.999) and time to access (47 seconds [interquartile range (IQR), 20-90 seconds] versus 31 seconds [IQR, 20-75 seconds]; P=.179) did not differ between the ultrasound and palpation groups, respectively. Pulse quality (absent, weak, strong) was independently associated with access failure in both groups (P<.001). Obesity was associated with access failure in the palpation group (P=.005), but not in the ultrasound group (P=.544). In 3/12 cases (25%) in the ultrasound group and 2/6 cases (33%) in the palpation group, the operator was able to establish radial access using the alternative method (P=.710). If palpation-guided radial access failed, an additional ultrasound-guided attempt before crossover to femoral access was associated with a shorter overall time to access (525 seconds [IQR, 462-567 seconds] versus 744 seconds [IQR, 722-788 seconds]; P=.016). CONCLUSIONS: Ultrasound-guided radial access seems to provide no substantial additional benefit over palpation-guided access alone. Attempting the alternative guiding methods to establish radial access before crossover to femoral access seems to be a reasonable approach.

Magnetic resonance imaging analysis of the spread of local anesthetic solution after ultrasound-guided lateral thoracic paravertebral blockade: a volunteer study.

BACKGROUND: This study was designed to examine the spread of local anesthetic (LA) via magnetic resonance imaging after a standardized ultrasound-guided thoracic paravertebral blockade. METHODS: Ten volunteers were enrolled in the study. We performed ultrasound-guided single-shot paravertebral blocks with 20 ml mepivacaine 1% at the thoracic six level at both sides on two consecutive days. After each paravertebral blockade, a magnetic resonance imaging investigation was performed to investigate the three-dimensional spread of the LA. In addition, sensory spread of blockade was evaluated via pinprick testing. RESULTS: The median (interquartile range) cranial and caudal distribution of the LA relative to the thoracic six puncture level was 1.0 (2.5) and 3.0 (0.75) [=4.0 vertebral levels] for the left and 0.5 (1.0) and 3.0 (0.75) [=3.5 vertebral levels] for the right side. Accordingly, the LA distributed more caudally than cranially. The median (interquartile range) number of sensory dermatomes which were affected by the thoracic paravertebral blockade was 9.8 (6.5) for the left and 10.7 (8.8) for the right side. The sensory distribution of thoracic paravertebral blockade was significantly larger compared with the spread of LA. CONCLUSIONS: Although the spread of LA was reproducible, the anesthetic effect was unpredictable, even with a standardized ultrasound-guided technique in volunteers. While it can be assumed that approximately 4 vertebral levels are covered by 20 ml LA, the somatic distribution of the thoracic paravertebral blockade remains unpredictable. In a significant percentage, the LA distributes into the epidural space, prevertebral, or to the contralateral side.

Analysis of multiple sclerosis lesions using a fusion of 3.0 T FLAIR and 7.0 T SWI phase: FLAIR SWI.

PURPOSE: To improve multiple sclerosis (MS) research by introducing a new type of contrast, namely, the combination of fluid-attenuated inversion recovery (FLAIR) data acquired at 3.0 T and 7.0 T susceptibility-weighted imaging (SWI) phase data. The approach of this new contrast is whole-brain coverage with 3.0 T-FLAIR data for lesion detection--currently limited at 7.0 T due to specific absorption rate (SAR) limits--overlaid with high-resolution, small vessel, and iron-related 7.0 T SWI contrast. Lesion analysis in terms of penetrating veins and local iron depositions were performed. MATERIALS AND METHODS: Data from 10 MS patients were acquired at 3.0 T and at 7.0 T. FLAIR data, acquired at 3.0 T, were registered to 7.0 T SWI phase data and SWI image processing was performed using 3.0 T FLAIR data instead of SWI magnitude data. RESULTS: A total of 299 MS plaques were detected in eight MS patients. Penetrating veins were found in 75 MS plaques, iron depositions in 48 MS plaques, and veins accompanied with iron depositions in 44 MS plaques. CONCLUSION: FLAIR-SWI provides radiologically known, hyperintense definition of MS lesions overlaid with high-resolution visualization of iron deposits and venous blood vessels and offers new insights into MS lesions.

Perceptibility and quantification of in-stent stenosis with six peripheral arterial stent types in vitro: comparison of 16-MDCT angiography, 64-MDCT angiography, and MR angiography.

OBJECTIVE: The purpose of this study was to evaluate and compare the perceptibility of 75% and 95% in-stent stenoses with CT angiography and MR angiography using six stent types in a phantom model. MATERIALS AND METHODS: Six different stent types were placed into tubes filled with contrast agent (ioversol or gadoteric acid), and nylon cylinders (8 mm diameter) bored in the central axis (2 and 4 mm) to mimic 75% and 95% stenoses were inserted into the stents inside the tubes. CT angiography (16- and 64-MDCT scanners using three different kernels at 120 and 140 kV) and MR angiography (1.5 T) were performed. On 2-mm coronal sections, signal intensities in the stenosed stents were compared with unstenosed segments. In addition, perceptibility of the residual lumen was assessed using a subjective score. Image analysis was performed by two experienced and blinded radiologists. RESULTS: Sixteen-slice CT angiography showed relative in-stent signal intensities of 72-87%, whereas 64-MDCT angiography showed relative in-stent signal intensities of 63-99%. Sixty-four-slice CT angiography showed nearly no difference between 75% and 95% stenoses in the subjective scores. The high-contrast kernel was superior to intermediate- and low-contrast kernels. MR angiography showed relative in-stent signal intensities of 57-98%. The presence of localized artifacts and resulting inhomogeneous luminal signal caused lower subjective perceptibility ratings than the objective score would suggest. CONCLUSION: CT angiography was superior in the differentiation between 95% stenoses and occlusions. 64-MDCT angiography was superior to 16-MDCT (mean +/- SD, 83.0 +/- 2.9 vs 78.3 +/- 3.3; p = 0.006), especially with high-contrast kernels (89.7 +/- 2.1 vs 78.3 +/- 3.3; p = 0.001). For detection of 75% stenoses, MR angiography seems to be suitable subjectively, even though no statistical significance was found.

64-Slice CT angiography of the abdominal aorta and abdominal arteries: comparison of the diagnostic efficacy of iobitridol 350 mgI/ml versus iomeprol 400 mgI/ml in a prospective, randomised, double-blind multi-centre trial.

PURPOSE: The purpose of this study was to assess the influence of iodine concentration on diagnostic efficacy in multi-detector-row computed tomography (MDCT) angiography of the abdominal aorta and abdominal arteries. METHODS: IRB approval and informed consent were obtained. In this double-blind trial, patients were randomised to undergo MDCT angiography of the abdominal arteries during administration of iobitridol (350 mgI/ml) or iomeprol (400 mgI/ml). Each centre applied its own technique for delivery of contrast medium, regardless of iodine concentration. Diagnostic efficacy, image quality, visualisation of the arterial wall and arterial enhancement were evaluated. A total of 153 patients received iobitridol and 154 received iomeprol. RESULTS: The ability to reach a diagnosis was "satisfactory" to "totally satisfactory" in 152 (99.3%) and 153 (99.4%) patients respectively. Image quality was rated as being "good" to "excellent" in 94.7 and 94.8% segments respectively. Similar results were observed for image quality of arterial walls (84.3 vs. 83.2%). The mean relative changes in arterial enhancement between baseline and arterial phase images showed no statistically significant differences. CONCLUSION: This study demonstrated the non-inferiority of the 350 versus 400 mgI/ml iodine concentration, in terms of diagnostic efficacy, in abdominal MDCT angiography. It also confirmed the high robustness and reliability of this technique across multi-national practices.

Carotid artery stenting: single-center experience over 11 years.

This article reports the results of carotid artery stenting during an 11-year period. Data from 168 carotid artery stenting procedures (symptomatic, n = 55; asymptomatic, n = 101; symptoms not accessible, n = 12) were retrospectively collected. Primary technical success rate, neurological events in-hospital, access-site complications, and contrast-induced nephropathy (n = 118) were evaluated. To evaluate the influence of experience in carotid artery stenting on intraprocedural neurologic complications, patients were divided into two groups. Group 1 included the first 80 treated patients, and group 2 the remainder of the patients (n = 88). In-stent restenoses at last-follow-up examinations (n = 89) were assessed. The overall primary technical success rate was 95.8%. The in-hospital stroke-death rate was 3.0% (n = 5; symptomatic, 5.4%; asymptomatic, 2.0%; p = 0.346). Neurologic complications were markedly higher in group 1 (4.2%; three major strokes; symptomatic, 2.8%, asymptomatic, 1.4%) compared to group 2 (2.4%; one major and one minor stroke-symptomatic, 1.2%, asymptomatic 1.2%), but this was not statistically significant. Further complications were access-site complications in 12 (7.1%), with surgical revision required in 1 (0.6%) and mild contrast-induced nephropathy in 1 (0.85%). Twenty-one (23.6%) patients had >50% in-stent restenosis during a mean follow-up of 28.2 months. In conclusion, advanced experience in carotid artery stenting leads to an acceptable periprocedural stroke-death rate. In-stent restenosis could be a critical factor during the follow-up course.