51
|
Crobeddu E, Lanzino G, Kallmes DF, Cloft HJ. Review of 2 decades of aneurysm-recurrence literature, part 2: Managing recurrence after endovascular coiling. AJNR Am J Neuroradiol 2013; 34:481-5. [PMID: 22422182 PMCID: PMC7964895 DOI: 10.3174/ajnr.a2958] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Cerebral aneurysms are treated to prevent hemorrhage or rehemorrhage. Angiographic recurrences following endovascular therapy have been a problem since the advent of this treatment technique, even though posttreatment hemorrhage remains rare. Notwithstanding its unclear clinical significance, angiographic recurrence remains not only a prime focus in the literature but also frequently leads to potentially risky retreatments. The literature regarding aneurysm recurrence following endovascular therapy, spanning 2 decades, is immense and immensely confusing. We review the topic of recurrence following endovascular treatment of cerebral aneurysms in an effort to distill it down to fundamental material relevant to clinical practice.
Collapse
Affiliation(s)
- E Crobeddu
- Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | | | | | | |
Collapse
|
52
|
Serafin Z, Strześniewski P, Lasek W, Beuth W. Time-resolved imaging of contrast kinetics does not improve performance of follow-up MRA of embolized intracranial aneurysms. Med Sci Monit 2012; 18:MT60-5. [PMID: 22739746 PMCID: PMC3560766 DOI: 10.12659/msm.883199] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background The use of contrast media and the time-resolved imaging of contrast kinetics (TRICKS) technique have some theoretical advantages over time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. We prospectively compared the diagnostic performance of TRICKS and TOF-MRA with digital subtracted angiography (DSA) in the assessment of occlusion of embolized aneurysms. Material/Methods Seventy-two consecutive patients with 72 aneurysms were examined 3 months after embolization. Test characteristics of TOF-MRA and TRICKS were calculated for the detection of residual flow. The results of quantification of flow were compared with weighted kappa. Intraobserver and interobserver reproducibility was determined. Results The sensitivity of TOF-MRA was 85% (95% CI, 65–96%) and of TRICKS, 89% (95% CI, 70–97%). The specificity of both methods was 91% (95% CI, 79–98%). The accuracy of the flow quantification ranged from 0.76 (TOF-MRA) to 0.83 (TRICKS). There was no significant difference between the methods in the area under the ROC curve regarding both the detection and the quantification of flow. Intraobserver reproducibility was very good with both techniques (kappa, 0.86–0.89). The interobserver reproducibility was moderate for TOF-MRA and very good for TRICKS (kappa, 0.74–0.80). Conclusions In this study, TOF-MRA and TRICKS presented similar diagnostic performance; therefore, the use of time-resolved contrast-enhanced MRA is not justified in the follow-up of embolized aneurysms.
Collapse
Affiliation(s)
- Zbigniew Serafin
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland.
| | | | | | | |
Collapse
|
53
|
Chandra T, Pukenas B, Mohan S, Melhem E. Contrast-enhanced magnetic resonance angiography. Magn Reson Imaging Clin N Am 2012; 20:687-98. [PMID: 23088945 DOI: 10.1016/j.mric.2012.08.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Magnetic resonance (MR) angiography is a powerful tool for the evaluation of cervical and intracranial vasculature. Both noncontrast and contrast-enhanced MR angiography can provide exquisite vascular contrast and detail without the use of ionizing radiation. More advanced techniques such as time-resolved MR angiography and parallel imaging provide dynamic information in rapid fashion. This article describes the basic principles and techniques of MR angiography image acquisition.
Collapse
Affiliation(s)
- Tushar Chandra
- Department of Radiology, Children's Hospital of Wisconsin, Milwaukee, WI, USA
| | | | | | | |
Collapse
|
54
|
Serafin Z, Strześniewski P, Lasek W, Beuth W. Comparison of remnant size in embolized intracranial aneurysms measured at follow-up with DSA and MRA. Neuroradiology 2012; 54:1381-8. [PMID: 22790180 PMCID: PMC3517706 DOI: 10.1007/s00234-012-1063-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 06/25/2012] [Indexed: 11/03/2022]
Abstract
INTRODUCTION The possibility of recanalization and the need for retreatment are the most important limitations of intracranial aneurysm embolization. The purpose of the study was to compare the size of aneurysm remnants measured at follow-up with three-dimensional digital subtracted angiography (3D-DSA) and magnetic resonance angiography (MRA). METHODS Twenty-six aneurysms were found incompletely occluded in 72 consecutively examined patients at a follow-up after 3 months. The diameters and volume of aneurysm remnants were compared between 3D-DSA, time-of-flight MRA (TOF-MRA), contrast-enhanced TOF-MRA (CE-TOF-MRA), and contrast-enhanced MRA (CE-MRA) at 1.5 T. RESULTS There was a significant correlation between remnant volumes calculated based on 3D-DSA and all MRA modalities. The intraobserver variability of the measurements ranged from 3.4 to 4.1 % and the interobserver variability from 5.8 to 7.3 %. There were no significant differences in the variability between the techniques. The mean residual filling volume ranged from 16.3 ± 19.0 mm(3) in TOF-MRA to 30.5 ± 44.6 mm(3) in 3D-DSA (P < 0.04). Significant differences were found in the volumes measured with 3D-DSA and CE-MRA as compared to TOF-MRA and CE-TOF-MRA (P < 0.01). There was a moderate significant correlation between the residual filling and the relative error of measurement in the case of TOF-MRA and CE-TOF-MRA. CONCLUSIONS TOF-MRA seems to underestimate the size of aneurysm remnants detected at follow-up and should not be used as a sole imaging method to decide on re-embolization.
Collapse
Affiliation(s)
- Zbigniew Serafin
- Department of Radiology and Diagnostic Imaging, Collegium Medicum, Nicolaus Copernicus University, ul. M. Skłodowskiej-Curie 9, 85-094, Bydgoszcz, Poland.
| | | | | | | |
Collapse
|
55
|
A systematic review of the utility of 1.5 versus 3 Tesla magnetic resonance brain imaging in clinical practice and research. Eur Radiol 2012; 22:2295-303. [PMID: 22684343 DOI: 10.1007/s00330-012-2500-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 04/05/2012] [Accepted: 04/09/2012] [Indexed: 10/28/2022]
Abstract
OBJECTIVE MRI at 3 T is said to be more accurate than 1.5 T MR, but costs and other practical differences mean that it is unclear which to use. METHODS We systematically reviewed studies comparing diagnostic accuracy at 3 T with 1.5 T. We searched MEDLINE, EMBASE and other sources from 1 January 2000 to 22 October 2010 for studies comparing diagnostic accuracy at 1.5 and 3 T in human neuroimaging. We extracted data on methodology, quality criteria, technical factors, subjects, signal-to-noise, diagnostic accuracy and errors according to QUADAS and STARD criteria. RESULTS Amongst 150 studies (4,500 subjects), most were tiny, compared old 1.5 T with new 3 T technology, and only 22 (15 %) described diagnostic accuracy. The 3 T images were often described as "crisper", but we found little evidence of improved diagnosis. Improvements were limited to research applications [functional MRI (fMRI), spectroscopy, automated lesion detection]. Theoretical doubling of the signal-to-noise ratio was not confirmed, mostly being 25 %. Artefacts were worse and acquisitions took slightly longer at 3 T. CONCLUSION Objective evidence to guide MRI purchasing decisions and routine diagnostic use is lacking. Rigorous evaluation accuracy and practicalities of diagnostic imaging technologies should be the routine, as for pharmacological interventions, to improve effectiveness of healthcare. KEY POINTS • Higher field strength MRI may improve image quality and diagnostic accuracy. • There are few direct comparisons of 1.5 and 3 T MRI. • Theoretical doubling of the signal-to-noise ratio in practice was only 25 %. • Objective evidence of improved routine clinical diagnosis is lacking. • Other aspects of technology improved images more than field strength.
Collapse
|
56
|
Pierot L, Portefaix C, Gauvrit JY, Boulin A. Follow-up of coiled intracranial aneurysms: comparison of 3D time-of-flight MR angiography at 3T and 1.5T in a large prospective series. AJNR Am J Neuroradiol 2012; 33:2162-6. [PMID: 22678846 DOI: 10.3174/ajnr.a3124] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Our aim was to compare 3D TOF-MRA sequences at 3T and 1.5T in the follow-up of coiled aneurysms. The follow-up of coiled intracranial aneurysms is mandatory to depict potential recanalization. 3D-TOF MRA is an appropriate tool for this purpose. MATERIALS AND METHODS DSA and 3D TOF-MRA at 1.5T and 3T were performed in a prospective series of 126 aneurysms in 96 patients (58 women, 38 men; age, 25-75 years; mean, 51.3 ± 11.3 years). DSA was the reference standard to which the accuracy of 3D TOF-MRA was compared. The quality of aneurysm occlusion was assessed independently and anonymously by a core lab by using a 3-grade scale (total occlusion, neck remnant, and aneurysm remnant). Adequate occlusion was defined as total occlusion or neck remnant and used in a 2-grade scale: adequate occlusion/aneurysm remnant. RESULTS With DSA, total occlusion was depicted in 58 aneurysms (46.0%); neck remnant, in 33 aneurysms (26.2%); and aneurysm remnant, in 35 aneurysms (27.8%). Adequate occlusion was seen in 91 cases (72.2%). A remnant (aneurysm or neck) was depicted in 68 cases (54.0%). For the 3 imaging techniques and regardless of scale used, the interobserver agreement was always greater at 3T than at 1.5T. SE and NPV for the prediction of aneurysm remnant versus adequate occlusion were higher at 3T than at 1.5T (SE 3T, 0.74; SE 1.5T, 0.54; NPV 3T, 0.90; NPV 1.5T, 0.85). CONCLUSIONS In this large prospective series of patients, 3D TOF-MRA was superior at 3T to 1.5T for the evaluation of coiled intracranial aneurysms.
Collapse
Affiliation(s)
- L Pierot
- Department of Radiology, Maison Blanche Hospital, University of Reims, Reims, France.
| | | | | | | |
Collapse
|
57
|
Pierot L, Portefaix C, Boulin A, Gauvrit JY. Follow-up of coiled intracranial aneurysms: comparison of 3D time-of-flight and contrast-enhanced magnetic resonance angiography at 3T in a large, prospective series. Eur Radiol 2012; 22:2255-63. [DOI: 10.1007/s00330-012-2466-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 03/07/2012] [Accepted: 03/23/2012] [Indexed: 10/28/2022]
|
58
|
Follow-up after embolization of ruptured intracranial aneurysms: a prospective comparison of two-dimensional digital subtraction angiography, three-dimensional digital subtraction angiography, and time-of-flight magnetic resonance angiography. Neuroradiology 2012; 54:1253-60. [PMID: 22488210 PMCID: PMC3509325 DOI: 10.1007/s00234-012-1030-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 03/12/2012] [Indexed: 10/29/2022]
Abstract
INTRODUCTION To prospectively compare of the diagnostic value of digital subtraction angiography (DSA) and time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. METHODS Seventy-two consecutive patients were examined 3 months after the embolization. The index tests included: two-dimensional DSA (2D-DSA), three-dimensional DSA (3D-DSA), and TOF-MRA. The reference test was a retrospective consensus between 2D-DSA images, 3D-DSA images, and source rotational DSA images. The evaluation included: detection of the residual flow, quantification of the flow, and validity of the decision regarding retreatment. Intraobserver agreement and interobserver agreement were determined. RESULTS The sensitivity and specificity of residual flow detection ranged from 84.6 % (2D-DSA and TOF-MRA) to 92.3 % (3D-DSA) and from 91.3 % (TOF-MRA) to 97.8 % (3D-DSA), respectively. The accuracy of occlusion degree evaluation ranged from 0.78 (2D-DSA) to 0.92 (3D-DSA, Cohen's kappa). The 2D-DSA method presented lower performance in the decision on retreatment than 3D-DSA (P < 0.05, ROC analysis). The intraobserver agreement was very good for all techniques (κ = 0.80-0.97). The interobserver agreement was moderate for TOF-MRA and very good for 2D-DSA and 3D-DSA (κ = 0.72-0.94). CONCLUSION Considering the invasiveness of DSA and the minor difference in the diagnostic performance between 3D-DSA and TOF-MRA, the latter method should be the first-line modality for follow-up after aneurysm embolization.
Collapse
|
59
|
Campeau NG, Huston J. Vascular disorders--magnetic resonance angiography: brain vessels. Neuroimaging Clin N Am 2012; 22:207-33, x. [PMID: 22548929 DOI: 10.1016/j.nic.2012.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Magnetic resonance angiography (MRA) of the brain obtained at 3 T imaging has made a significant clinical impact. MRA benefits from acquisition at higher magnetic field strength because of higher available signal-to-noise ratio and improved relative background suppression due to magnetic field strength-related T1 lengthening. Parallel imaging techniques are ideally suited for high-field MRA. Many of the developments that have made 3 T MRA of the brain successful can be regarded as enabling technologies that are essential for further development of 7 T MRA, which brings additional challenges.
Collapse
Affiliation(s)
- Norbert G Campeau
- Division of Neuroradiology, Mayo Clinic, West 2 Mayo Building, 200 First Street Southwest, Rochester, MN 55905, USA.
| | | |
Collapse
|
60
|
Spilberg G, Carniato SL, King RM, van der Bom IMJ, Mehra M, Walvick RP, Wakhloo AK, Gounis MJ. Temporal evolution of susceptibility artifacts from coiled aneurysms on MR angiography: an in vivo canine study. AJNR Am J Neuroradiol 2011; 33:655-60. [PMID: 22194374 DOI: 10.3174/ajnr.a2831] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Intracranial aneurysms treated by coiling have a risk for recurrence, requiring surveillance imaging. MRA has emerged as an attractive technique for postcoiling aneurysm imaging. Previous research has evaluated MR imaging artifacts of the coil mass in vitro. Our aim in this study was to evaluate MR imaging artifacts of coiled aneurysms in vivo with time. MATERIALS AND METHODS Four sidewall aneurysms were created in each of 4 dogs. Aneurysms were embolized receiving only 1 type of coils. After embolization, the animals were transferred to MR imaging, which included axial 3D TOF MRA (TEs, 3.5, 5, and 6.9 ms), phase-contrast MRA, and coronal CE-MRA. MR imaging studies were repeated at 1, 4, 6, 8, 14, and 28 weeks. We calculated an OEF: OEF = V(A)/V(CM), where the numerator represents the volume of the MR imaging artifacts and the denominator is the true volume of the coil mass measured by 3D RA. RESULTS OEFs were largest immediately after embolization and showed a gradual decay until approximately 4 weeks, when there was stabilization of the size of the artifacts. By 4 weeks, there was mild coil compaction (average coil mass volume decrease of 7.8%); however, the OEFs decreased by 25% after 4 weeks (P < .001). CONCLUSIONS MR imaging susceptibility artifacts change with time, being maximal in the postembolization setting and decaying until 4 weeks. The clinical implications of this study are that baseline MRA for comparison with future imaging should be acquired at a minimum of 1 week after the procedure.
Collapse
Affiliation(s)
- G Spilberg
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
| | | | | | | | | | | | | | | |
Collapse
|
61
|
Killer M, McCoy MR, Vestal MC, Weitgasser L, Cruise GM. Use of CT angiography in comparison with other imaging techniques for the determination of embolus and remnant size in experimental aneurysms embolized with hydrogel filaments. AJNR Am J Neuroradiol 2011; 32:923-8. [PMID: 21511861 DOI: 10.3174/ajnr.a2554] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Beam-hardening artifacts in CTA can be greatly reduced by using metal-free coils for aneurysm embolization. We compared the embolic masses and remnants of experimental rabbit aneurysms coiled with hydrogel filaments by using DSA, CTA and histology. MATERIALS AND METHODS Embolization of 12 rabbit bifurcation aneurysms was performed with detachable hydrogel filaments. Six aneurysms were embolized as completely as possible, and 6 aneurysms were embolized incompletely to intentionally leave remnants. Three aneurysms in each group underwent follow-up at 4 and 13 weeks. DSA, MRA, and CTA were performed immediately before sacrifice. The harvested aneurysms were evaluated histologically. For each imaging technique, the areas of the embolic mass and remnant were determined by using image analysis. Results were compared by using paired t tests. RESULTS CTAs were suitable for quantification of the embolus and remnant areas because only small streaking artifacts were evident. The areas of the embolus were larger on CTA compared with DSA and histologic sections. The areas of the remnant were larger on CTA and MRA compared with DSA and histologic sections. Like DSA and MRA, CTA was suitable for determining whether aneurysm retreatment was necessary, provided that loops of hydrogel filaments were not present in the parent artery. CONCLUSIONS We demonstrated that CTA is a technique with potential for surveillance of aneurysms treated with hydrogel filaments. Additional work is required to determine the accuracy of the technique compared with currently accepted imaging modalities of DSA and MRA.
Collapse
Affiliation(s)
- M Killer
- Neuroscience Institute/Department of Neurology, Paracelsus Medical University, Christian Doppler Clinic, Salzburg, Austria.
| | | | | | | | | |
Collapse
|
62
|
Abstract
OBJECTIVE This article reviews current neuroimaging techniques used for screening, diagnosis, and follow-up of patients with intracranial aneurysms as well as neuroendovascular therapeutic options available to patients. CONCLUSION The diagnosis and management of intracranial aneurysms have evolved dramatically in the past 20 years. MR angiography and CT angiography allow radiologists to reliably and noninvasively diagnose most intracranial aneurysms. Nonoperative endovascular techniques for treating intracranial aneurysms are now making treatment increasingly safer and more effective.
Collapse
|
63
|
Daugherty WP, Rad AE, White JB, Meyers PM, Lanzino GL, Cloft HJ, Gordon J, Kallmes DF. Observer agreement regarding the necessity of retreatment of previously coiled recurrent cerebral aneurysms. AJNR Am J Neuroradiol 2011; 32:566-9. [PMID: 21252043 DOI: 10.3174/ajnr.a2336] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The decision regarding whether or not to retreat a previously treated aneurysm not only directly impacts patient care but also serves as a primary outcome measure in numerous, leading randomized controlled trials of modified coils. Our aim was to determine the degree of interobserver variability regarding the need and type of treatment for recurrent aneurysms following coil embolization. MATERIALS AND METHODS Twenty-seven previously treated recurrent aneurysms were identified. Five independent readers rated each aneurysm on a 5-point scale: 1, definitely do not retreat; 2, probably do not retreat; 3, unsure; 4, probably retreat; and 5, definitely retreat. The readers noted, in grades 2-5, the type of retreatment preferred, including simple coiling, balloon- or stent-assist coiling, or surgical clipping. Intraobserver agreement κ was calculated. Retreatment recommendations were evaluated between observers by using a Wilcoxon signed rank comparison. Descriptive statistics were performed for categoric treatment-type comparisons. RESULTS At least 2- or 3-point differences between 2 readers were present in 17 (63%) and 11 (41%) of 27 cases, respectively. The median κ was 0.27 (range, 0.04-0.43), which indicates fair agreement. Differences between readers varied, with readers 4 and 5 more often recommending retreatment compared with reviewers 1-3 (P < .05). Wide variation was noted in treatment approach, with recommendations for surgical clipping ranging from 2 (7%) to 18 (67%) of 27 cases between readers 1 and 5. CONCLUSIONS The current study demonstrates substantial variability among observers not only in whether to retreat a recurrent aneurysm but also how to treat it. These findings suggest that patient management varies widely across treating physicians and also calls into question the use of "retreatment" as an objective end point in clinical trials.
Collapse
Affiliation(s)
- W P Daugherty
- Department of Neurosurgery, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | | | | | | | | | | |
Collapse
|
64
|
Serafin Z, Strześniewski P, Lasek W, Beuth W. Methods and time schedule for follow-up of intracranial aneurysms treated with endovascular embolization: a systematic review. Neurol Neurochir Pol 2011; 45:421-30. [DOI: 10.1016/s0028-3843(14)60309-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
65
|
Nakiri GS, Santos AC, Abud TG, Aragon DC, Colli BO, Abud DG. A comparison between magnetic resonance angiography at 3 Teslas (time-of-flight and contrast-enhanced) and flat-panel digital subtraction angiography in the assessment of embolized brain aneurysms. Clinics (Sao Paulo) 2011; 66:641-8. [PMID: 21655760 PMCID: PMC3093796 DOI: 10.1590/s1807-59322011000400020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Accepted: 01/25/2011] [Indexed: 11/21/2022] Open
Abstract
PURPOSE To compare the time-of-flight and contrast-enhanced- magnetic resonance angiography techniques in a 3 Tesla magnetic resonance unit with digital subtraction angiography with the latest flat-panel technology and 3D reconstruction in the evaluation of embolized cerebral aneurysms. INTRODUCTION Many embolized aneurysms are subject to a recurrence of intra-aneurismal filling. Traditionally, imaging surveillance of coiled aneurysms has consisted of repeated digital subtraction angiography. However, this method has a small but significant risk of neurological complications, and many authors have advocated the use of noninvasive imaging methods for the surveillance of embolized aneurysms. METHODS Forty-three aneurysms in 30 patients were studied consecutively between November 2009 and May 2010. Two interventional neuroradiologists rated the time-of-flight-magnetic resonance angiography, the contrast-enhanced-magnetic resonance angiography, and finally the digital subtraction angiography, first independently and then in consensus. The status of aneurysm occlusion was assessed according to the Raymond scale, which indicates the level of recanalization according to degrees: Class 1: excluded aneurysm; Class 2: persistence of a residual neck; Class 3: persistence of a residual aneurysm. The agreement among the analyses was assessed by applying the Kappa statistic. RESULTS Inter-observer agreement was excellent for both methods (K = 0.93; 95 % CI: 0.84-1). Inter-technical agreement was almost perfect between time-of-flight-magnetic resonance angiography and digital subtraction angiography (K = 0.98; 95 % CI: 0.93-1) and between time-of-flight-magnetic resonance angiography and contrast-enhanced-magnetic resonance angiography (K = 0.98; 95% CI: 0.93-1). Disagreement occurred in only one case (2.3%), which was classified as Class I by time-of-flight-magnetic resonance angiography and Class II by digital subtraction angiography. The agreement between contrast-enhanced-magnetic resonance angiography and digital subtraction angiography was perfect (K = 1; 95% CI: 1-1). In three patients, in-stent stenosis was identified by magnetic resonance angiography but not confirmed by digital subtraction angiography. CONCLUSION Digital subtraction angiography and both 3T magnetic resonance angiography techniques have excellent reproducibility for the assessment of aneurysms embolized exclusively with coils. In those cases also treated with stent remodeling, digital subtraction angiography may still be necessary to confirm eventual parent artery stenosis, as identified by magnetic resonance angiography.
Collapse
Affiliation(s)
- Guilherme S Nakiri
- Division of Radiology, Department of Internal Medicine, Medical School of Ribeirão Preto, University of São Paulo, SP, Brazil.
| | | | | | | | | | | |
Collapse
|
66
|
Tailor J, Goetz P, Chandrashekar H, Stephen T, Schiariti M, Grieve J, Watkins L, Brew S, Robertson F, Kitchen N. Stability of ruptured intracranial aneurysms treated with detachable coils: is delayed follow-up angiography warranted? Br J Neurosurg 2010; 24:405-9. [DOI: 10.3109/02688697.2010.487130] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|