[Show abstract][Hide abstract] ABSTRACT: To compare the accuracy of C-arm computed tomography (CT) and digital subtraction angiography (DSA) in detecting incomplete stent expansion (ISE) after superficial femoral artery (SFA) stenting using intravascular ultrasound (IVUS) as a gold standard.
Fifty patients with symptomatic SFA occlusive disease requiring angioplasty were prospectively included. Once technical success (<30 % residual stenosis) was obtained on post-procedural DSA, C-arm CT and IVUS were acquired. DSA and C-arm CT examinations were reviewed by 2 investigators and correlated with IVUS. C-arm CT image quality was rated on a four-point scale. Doppler ultrasound was performed at 1-year follow-up.
The ankle-brachial index was 0.69 ± 0.10 and 0.99 ± 0.40, respectively, pre- and post-procedure. C-arm CT imaging quality was rated as good or excellent in 80 %. In-stent minimal luminal diameter (MLD) was evaluated at 4.71 ± 0.7 mm on DSA, 3.39 ± 0.6 mm on IVUS, and 3.12 ± 0.9 mm on C-arm CT. Compared to IVUS, DSA demonstrated an overestimation of MLD (p = 0.0001), an underestimation of ISE (DSA = 18.8 % ± 7.6; IVUS = 29.8 % ± 9) (p < 0.0001), and a poor inter-technique intra-class correlation coefficient (ICC = 0.24). No difference was observed between IVUS and C-arm CT in ISE as calculated by diameter (29.8 ± 9 vs. 28.2 ± 12.5 %, p = 0.5) and area (30.2 ± 8.4 vs. 33.3 ± 9.5 %, p = 0.2). Inter-technique ICC between C-arm CT and IVUS was 0.72 [95 %CI 0.49; 0.85] for MLA measurements. The inter-observer ICC for MLD and MLA measurements on C-arm CT were, respectively, estimated at 0.75 [95 % CI 0.40, 0.89] and 0.77 [95 % CI 0.43, 0.90)].
C-arm CT presents a better correlation with IVUS than DSA to determine lumen diameter and ISE immediately after percutaneous revascularization.
[Show abstract][Hide abstract] ABSTRACT: Many adrenal venous sampling (AVS) protocols require repeated samplings before and after adrenocorticotrophic hormone (ACTH) stimulation. Maintaining catheter selectivity in the adrenal vein over time is essential but can be challenging, especially in the short right adrenal vein, where the catheter is often in an unstable position. The aim of our study was to evaluate guide wire insertion into the right adrenal vein catheter to sustain AVS selectivity (adrenal/peripheral cortisol ratio [Ca/Cp]) over time.
This retrospective investigation was approved by our institutional review board, and informed consent was obtained. A 0.014-inch guide wire was inserted in the right adrenal vein 5F catheter to secure its positioning and to facilitate blood sampling. Plasma cortisol levels from the left and right adrenal veins and left iliac vein were assessed in 117 consecutive patients undergoing bilateral, simultaneous sets of AVS at -5 and 0 min (baseline) and 5, 10, and 15 min after intravenous bolus of 250 μg ACTH (stimulated). Ca/Cp ratios of ≥2 for baseline and >10 for stimulated AVS were considered selective.
The first sampling, at time -5 min, was nonselective in 41 of 116 (35.3 %) right and 30 of 116 (25.9 %) left AVSs retained for analysis. In patients with a selective first sampling, 74 of 75 (98.7 %) right and 85 of 86 (98.8 %) left AVSs were selective in all post-ACTH samplings. Right and left selectivity rates were not statistically different (p > 0.87). No complications arose from guide wire insertion.
Guide wire insertion into the right adrenal vein catheter is safe and effective to maintain AVS selectivity over time.
CardioVascular and Interventional Radiology 12/2013; DOI:10.1007/s00270-013-0794-9 · 2.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To evaluate venous malformation (VM) volume and contrast-enhancement analysis on magnetic resonance imaging (MRI) compared with diameter evaluation.
Baseline MRI was undertaken in 44 patients, 20 of whom were followed by MRI after sclerotherapy. All patients underwent short-tau inversion recovery (STIR) acquisitions and dynamic contrast assessment. VM diameters in three orthogonal directions were measured to obtain the largest and mean diameters. Volumetric reconstruction of VM was generated from two orthogonal STIR sequences and fused with acquisitions after contrast medium injection. Reproducibility (interclass correlation coefficients [ICCs]) of diameter and volume measurements was estimated. VM size variations in diameter and volume after sclerotherapy and contrast enhancement before sclerotherapy were compared in patients with clinical success or failure.
Inter-observer ICCs were similar for diameter and volume measurements at baseline and follow-up (range 0.87-0.99). Higher percentages of size reduction after sclerotherapy were observed with volume (32.6 ± 30.7 %) than with diameter measurements (14.4 ± 21.4 %; P = 0.037). Contrast enhancement values were estimated at 65.3 ± 27.5 % and 84 ± 13 % in patients with clinical failure and success respectively (P = 0.056).
Venous malformation volume was as reproducible as diameter measurement and more sensitive in detecting therapeutic responses. Patients with better clinical outcome tend to have stronger malformation enhancement.
• Magnetic resonance imaging readily demonstrates diameters and volumes of venous malformations • MRI diameter calculations are reproducible in estimating the size of venous malformations • But volumetric models of malformations are more sensitive in detecting therapeutic response • Dynamic enhancement is also better assessed with automated volumetric software • Volumetric analysis of malformations offers promise to guide therapy and assess response.
European Radiology 11/2013; 24(2). DOI:10.1007/s00330-013-3066-9 · 4.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To evaluate the impact of cone-beam computed tomography (CT) during sclerotherapy of low-flow vascular malformations.
Eighty-seven cone-beam CT examinations were acquired during 81 sclerotherapy treatments of low-flow malformations in 48 patients: 81 were performed to evaluate sclerosing agent diffusion and six were performed to evaluate needle or catheter positioning before injection of therapeutic agent. Image quality was rated by two observers. Clinical impact of cone-beam CT in the assessment of therapeutic agent diffusion, needle or catheter positioning, subsequent treatment planning, and complication detection was evaluated. The κ-statistic was used to assess interobserver reliability and proportions, with associated 95% confidence intervals (CIs).
All cone-beam CT images were successfully acquired. Image quality was rated as excellent or good for the majority of studies, with substantial interobserver reliability (κ = 0.648). Cone-beam CT studies improved assessment of therapeutic agent diffusion in 83% of cases (67 of 81; 95% CI, 75%-91%) for observer 1, who had access to ultrasound, fluoroscopic, and digital subtraction angiographic (DSA) imaging, and in 95% of cases (77 of 81; 95% CI, 90%-100%) for observer 2, who had access to only stored fluoroscopic spot radiographs and DSA images. Cone-beam CT impacted planning of the next treatment session in 49% of cases (40 of 81; 95% CI, 38%-60%). In 7% of cases (six of 81; 95% CI, 1%-13%), complications such as migration of therapeutic agent or compression of upper airways were detected that were not seen with other imaging.
Cone-beam CT can be a useful adjunctive imaging tool, providing information to help decision-making during percutaneous sclerotherapy and ongoing management of low-flow vascular malformations.
Journal of vascular and interventional radiology: JVIR 07/2013; 24(7):981-988.e2. DOI:10.1016/j.jvir.2013.03.035 · 2.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: PURPOSE
To evaluate the sensitivity and specificity of non-enhanced CT to detect PAVMs reperfusion after embolization.
METHOD AND MATERIALS
The imaging files of all patients who had pulmonary angiography follow-up after PAVM embolization in our center from 2000 to 2010 were reviewed. PAVM feeding artery, draining vein and aneurismal sac diameters were measured on non-enhanced CT before and after embolization. Follow-up pulmonary angiography was the gold standard to assess reperfusion. ROC curves were used to assess sensitivity and specificity according to the percentage of diameter reduction.
From the 67 patients who had PAVM embolization, 39 (58%) had no follow-up angiography, 9 (13%) no longer had pre or post embolization CT available and 19 (28%) patients had 52 PAVMs assessed by pulmonary angiography, performed during additional PAVMs embolizations (5 patients, 26%) or because of suspicion of PAVM reperfusion on CT (14 patients, 74%). Twenty-seven (51%) PAVMs were occluded and 25 (49%) were reperfused, 18 (72%) of these were re-embolized. Mean diameter reduction in occluded versus reperfused PAVMs were respectively 51,6% +/- 22,6% versus 26,5% +/- 20,7% for the vein and 60,1% +/- 19,5% versus 25,9% +/- 23,8% for the aneurismal sac. A 50% diameter reduction of the PAVM feeding artery, vein and aneurismal sac respectively showed a sensitivity/specificity of 76%/78%, 88%/62%, and 72%/78% for reperfusion.
There is a wide overlap in diameter reduction between occluded and reperfused PAVMs after embolization. A 50% diameter reduction cutoff for the aneurismal sac on CT would still miss 25% of reperfused PAVMs.
Sensitivity and specificity of non-enhanced chest CT to detect PAVM reperfusion after embolization is highly dependant on the selected PAVM diameter reduction threshold, which should be standardized.
Radiological Society of North America 2011 Scientific Assembly and Annual Meeting; 11/2011
[Show abstract][Hide abstract] ABSTRACT: PURPOSE
Assessment of adrenal vein catheter selectivity is essential before interpretation of adrenal venous sampling (AVS) which is the gold standard to identify lateralized, surgically curable source of primary aldosteronism. The aim of this study is to evaluate the basal adrenal/peripheral aldosterone (Aa/Ap) ratio to assess AVS selectivity when the adrenal/peripheral cortisol (Ca/Cp) ratio does not reach the selectivity threshold (Ca/Cp >2).
METHOD AND MATERIALS
We compared the plasma cortisol and aldosterone levels from the left and right adrenal veins and left iliac vein in 91 consecutive patients undergoing 97 bilateral simultaneous AVS. These AVS were performed - 5 and 0 minutes before (basal) and +5, +10 and +15 minutes after intravenous bolus administration of 250 µg ACTH (stimulated). Basal Aa/Ap and Ca/Cp ratio ≥ 2 were considered selective. The gold standard for selectivity was a Ca/Cp ratio >10 after ACTH stimulation.
According to the gold standard (Ca/Cp ratio >10 after ACTH stimulation), 175/194 (90.2%) AVS were selective, 83/97 (85.6%) on the right and 92/97 (94.8%) of the left side. The mean basal aldosterone and cortisol ratio were 39.7 (+/- 87.8) and 7.5 (+/- 11) respectively. Selectivity of basal cortisol and aldosterone ratio ≥ 2 were 71.4% (275/385) and 80.3% (310/386) respectively. Basal cortisol and aldosterone ratio were concordant for selectivity in 301/384 (78.4%) samplings, 163/192 (84.9%) on the right and 138/192 (71.9%) on the left side. Sensitivity and specificity to detect selectivity were respectively 78.1% and 89.2% for the basal cortisol ratio, 87% and 83.8% for the basal aldosterone ratio and 94.2% and 83.8% when based on either the cortisol or the aldosterone ratio (sensitivity p<0.001; specificity p=0.48 versus based on cortisol ratio only).
Many basal AVS with a cortisol selectivity ratio <2 are selective and appropriate for lateralization assessment. The basal aldosterone selectivity ratio can identify a significant number of these diagnostic AVS that do not meet the standard cortisol selectivity criteria, with no significant reduction of the specificity of the test.
The use of the basal aldosterone selectivity ratio to assess AVS selectivity significantly improves the number of interpretable tests in comparison to the use of the cortisol selectivity ratio alone.
Radiological Society of North America 2011 Scientific Assembly and Annual Meeting; 11/2011
[Show abstract][Hide abstract] ABSTRACT: To compare different methods measuring abdominal aortic aneurysm (AAA) maximal diameter (Dmax) and its progression on multidetector computed tomography (MDCT) scan.
Forty AAA patients with two MDCT scans acquired at different times (baseline and follow-up) were included. Three observers measured AAA diameters by seven different methods: on axial images (anteroposterior, transverse, maximal, and short-axis views) and on multiplanar reformation (MPR) images (coronal, sagittal, and orthogonal views). Diameter measurement and progression were compared over time for the seven methods. Reproducibility of measurement methods was assessed by intraclass correlation coefficient (ICC) and Bland-Altman analysis.
Dmax, as measured on axial slices at baseline and follow-up (FU) MDCTs, was greater than that measured using the orthogonal method (p = 0.046 for baseline and 0.028 for FU), whereas Dmax measured with the orthogonal method was greater those using all other measurement methods (p-value range: <0.0001-0.03) but anteroposterior diameter (p = 0.18 baseline and 0.10 FU). The greatest interobserver ICCs were obtained for the orthogonal and transverse methods (0.972) at baseline and for the orthogonal and sagittal MPR images at FU (0.973 and 0.977). Interobserver ICC of the orthogonal method to document AAA progression was greater (ICC = 0.833) than measurements taken on axial images (ICC = 0.662-0.780) and single-plane MPR images (0.772-0.817).
AAA Dmax measured on MDCT axial slices overestimates aneurysm size. Diameter as measured by the orthogonal method is more reproducible, especially to document AAA progression.
[Show abstract][Hide abstract] ABSTRACT: To evaluate the efficacy and safety of percutaneous renal artery embolization (RAE) of iatrogenic vascular kidney injuries and the effects of RAE on renal function and arterial blood pressure (BP).
Over a 12-year period, 50 consecutive patients with severe hemorrhage after iatrogenic arterial kidney injuries underwent RAE. Technical success was defined as occlusion of the bleeding site, and clinical success was defined as complete bleeding cessation. The effects on renal function and arterial BP were assessed by comparing the estimated glomerular filtration rate (eGFR), renal function stage (National Kidney Foundation scale), systolic BP, and BP stage (European Society of Hypertension classification) before and after RAE.
RAE was technically successful in 49 patients (98%). Two patients were lost to follow-up after RAE. Clinical success was obtained in 40 (83%), 45 (94%), and 47 patients (98%), respectively, at 24, 48, and 96 hours after RAE. Three patients (6%) had minor complications, and one patient (2%) died within 30 days after RAE. Follow-up renal function data (mean, 4 mo) were available for 33 patients (66%). No statistically significant differences in eGFR (P = .186) or renal function stage (P = .183) were apparent after RAE. Follow-up BP data (mean, 3 mo) were available for 28 patients (56%). There were no significant differences in systolic BP (P = .233) or BP stage (P = .745) after RAE.
Embolization of iatrogenic renal artery injuries is safe and associated with high technical and clinical success rates. It is not associated with a significant worsening of renal function or increase in BP.
Journal of vascular and interventional radiology: JVIR 08/2011; 22(11):1563-8. DOI:10.1016/j.jvir.2011.06.020 · 2.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The recent technological developments of CT and MR units enable fast angiographic acquisitions with an improved spatial and temporal resolution. With advanced 3D visualisation, image post-processing and vessel wall-imaging, these technologies are now almost replacing diagnostic angiography that is now mainly indicated in case of suboptimal computed tomography angiography (CTA) or magnetic resonance angiography (MRA) examinations. Catheter angiography is now used to guide endovascular therapy and the planning of endovascular intervention will rely mainly on CTA or MRA examinations. The relative indications of MRA and CTA for the assessment and follow-up of peripheral arterial disease are based on the clinical indication, potential contraindication and the accessibility. We will review in this chapter, the technical requirements to perform adequate CTA and MRA examination, the relative indications of both modalities for the diagnosis and management of peripheral arterial occlusive disease (PAOD) and abdominal and peripheral aneurysm diseases. The main imaging features observed in these patients will be detailed.
[Show abstract][Hide abstract] ABSTRACT: To validate the reproducibility and accuracy of a software dedicated to measure abdominal aortic aneurysm (AAA) diameter, volume and growth over time.
A software enabling AAA segmentation, diameter and volume measurement on computed tomography angiography (CTA) was tested. Validation was conducted in 28 patients with an AAA having 2 consecutive CTA examinations. The segmentation was performed twice by a senior radiologist and once by 3 medical students on all 56 CTAs. Intra and inter-observer reproducibility of D-max and volumes values were calculated by intraclass correlation coefficient (ICC). Systematic errors were evaluated by Bland-Altman analysis. Differences in D-max and volume growth were compared with paired Student's t-tests.
Mean D-max and volume were 49.6±6.2mm and 117.2±36.2ml for baseline and 53.6±7.9mm and 139.6±56.3ml for follow-up studies. Volume growth (17.3%) was higher than D-max progression (8.0%) between baseline and follow-up examinations (p<.0001). For the senior radiologist, intra-observer ICC of D-max and volume measurements were respectively estimated at 0.997 (≥0.991) and 1.000 (≥0.999). Overall inter-observer ICC of D-max and volume measurements were respectively estimated at 0.995 (0.990-0.997) and 0.999 (>0.999). Bland-Altman analysis showed excellent inter-reader agreement with a repeatability coefficient <3mm for D-max, <7% for relative D-max growth, <6ml for volume and <6% for relative volume growth.
Software AAA volume measurements were more sensitive than AAA D-max to detect AAA growth while providing an equivalent and high reproducibility.
European journal of radiology 05/2011; 81(8):1688-94. DOI:10.1016/j.ejrad.2011.04.044 · 2.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to evaluate the usefulness of renal length, volume, and resistive index measurements at Doppler ultrasound and MR angiography in predicting improvement after renal angioplasty.
Fifty-one patients underwent Doppler ultrasound examinations and MR angiography before percutaneous transluminal renal angioplasty. Renal length, total and cortical volumes, and resistive index were calculated. Combinations of length, volume, and resistive index measurements were correlated with improvement in blood pressure and renal function after percutaneous transluminal renal angioplasty. Thresholds for improving patient selection were chosen after analysis of receiver operating characteristics curves.
Lower total and cortical volumes on MR angiograms and shorter kidney length on Doppler ultrasound images were found among patients with successful blood pressure control (p = 0.042, p = 0.035, and p = 0.016, respectively). Renal length measured with Doppler ultrasound and cortical volume measured with MR angiography weighted by resistive index were the best predictive factors (p = 0.004, p = 0.006). Using a threshold of renal length-resistive index product less than 7 cm, therapeutic response was predicted with a sensitivity of 87% and specificity of 50%, whereas with a threshold value of 52 mL/m(2) for cortical renal volume-resistive index product divided by body surface area, sensitivity of 86% and specificity of 50% were obtained.
Renal length and volume combined with resistive index measurements appear to be predictive of therapeutic response after percutaneous transluminal renal angioplasty.
American Journal of Roentgenology 05/2010; 194(5):1365-72. DOI:10.2214/AJR.09.3558 · 2.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To evaluate the safety and effectiveness of Amplatzer vascular plugs (AVPs) for percutaneous closure of arteries feeding pulmonary arteriovenous malformations (PAVMs).
Over a 45-month period, 24 consecutive patients with at least one PAVM treated with an AVP were selected from a database on patients with a PAVM who received embolotherapy. Immediate technical success was defined as the complete absence of flow through the PAVM after embolization without the need for additional embolization material. Success on follow-up imaging was defined as a reduction in size of at least 70% of the aneurysm or draining vein on follow-up computed tomography or the absence of flow through the PAVM on a subsequent pulmonary angiogram.
Thirty-seven AVPs were used to close 36 feeding arteries in 35 PAVMs in seven male and 17 female patients aged 11-86 years (mean age, 50 y). Technical success was achieved in 35 feeding arteries (97%). One feeding artery required two AVPs for closure. There were no immediate procedure-related complications. At a mean clinical follow-up of 322 days (range, 1-1,126 d), all patients were alive without new PAVM-related complications. Imaging follow-up was available for 29 embolized vessels (81%) with a mean follow-up of 418 days (range, 40-937 d), and recanalization occurred in two treated vessels (7%).
AVPs are safe and effective for closure of PAVMs feeding vessels that can be reached with a guiding catheter, with an acceptable rate of recanalization.
Journal of vascular and interventional radiology: JVIR 03/2010; 21(5):649-56. DOI:10.1016/j.jvir.2010.01.026 · 2.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To compare the reproducibility and accuracy of abdominal aortic aneurysm (AAA) maximal diameter (D-max) measurements using segmentation software, with manual measurement on double-oblique MPR as a reference standard.
The local Ethics Committee approved this study and waived informed consent. Forty patients (33 men, 7 women; mean age, 72 years, range, 49-86 years) had previously undergone two CT angiography (CTA) studies within 16 ± 8 months for follow-up of AAA ≥ 35 mm without previous treatment. The 80 studies were segmented twice using the software to calculate reproducibility of automatic D-max calculation on 3D models. Three radiologists reviewed the 80 studies and manually measured D-max on double-oblique MPR projections. Intra-observer and inter-observer reproducibility were calculated by intraclass correlation coefficient (ICC). Systematic errors were evaluated by linear regression and Bland-Altman analyses. Differences in D-max growth were analyzed with a paired Student's t-test.
The ICC for intra-observer reproducibility of D-max measurement was 0.992 (≥ 0.987) for the software and 0.985 (≥ 0.974) and 0.969 (≥ 0.948) for two radiologists. Inter-observer reproducibility was 0.979 (0.954-0.984) for the three radiologists. Mean absolute difference between semi-automated and manual D-max measurements was estimated at 1.1 ± 0.9 mm and never exceeded 5mm.
Semi-automated software measurement of AAA D-max is reproducible, accurate, and requires minimal operator intervention.
European journal of radiology 12/2009; 77(3):502-8. DOI:10.1016/j.ejrad.2009.07.027 · 2.37 Impact Factor