Postoperative three-dimensional CT angiography after cerebral aneurysm clipping with titanium clips: detection with single detector CT. Comparison with intra-arterial digital subtraction angiography
Introduction
Conventional intra-arterial digital subtraction angiography (IADSA) is the reference standard for diagnostic work-up of cerebral aneurysm. However, less-invasive imaging techniques such as magnetic resonance angiography (MRA) and three-dimensional computed tomography angiography (3D-CTA) have been widely used for preoperative evaluation of cerebral aneurysm recently.1, 2, 3, 4, 5, 6, 7 Several authors have already noted that diagnostic accuracies of 3D-CTA are comparable to IADSA, particularly in medium-sized aneurysms≥3 mm.1, 2, 3, 4, 5, 6, 7
Postoperative confirmations of the clipped cerebral aneurysms are generally performed using IADSA, as the significant artefacts from surgical clips interfere with image quality of MRA and 3D-CTA after aneurysm surgery. Paramagnetic titanium clips for magnetic resonance imaging (MRI) have recently become widespread in clinical use. These clips are also expected to produce smaller artefacts, allowing evaluation using 3D-CTA after clipping surgeries.
A few studies comprising small numbers of patients or using phantoms have examined the usefulness of postoperative 3D-CTA evaluation for the clipped aneurysms.8, 9, 10, 11, 12 However, no clinical studies involving large patient populations have investigated the diagnostic accuracy of postoperative 3D-CTA. The present study determined the diagnostic accuracy of 3D-CTA using surface-shaded display (SSD) or volume rendering (VR), in the detection of neck remnants after aneurysmal clipping.
Section snippets
Materials and methods
Fifty-seven consecutive patients (77 aneurysms; 16 men, 41 women) who underwent clipping surgery for cerebral aneurysms in our hospital between April 1999 and December 2002 comprised the study group. The mean age of patients was 59.8 years (range, 40–74 years). The locations of the aneurysms are listed in Table 1. Patients were assessed using IADSA and 3D-CTA postoperatively. All patients underwent surgery using titanium alloy clips (Yasargil titanium aneurysm clip; Aesculap AG, Tüttlingen,
Diagnostic accuracy
A total of 13 neck remnants among the 77 clipped aneurysms (16.9%) were confirmed by consensus of the three neuroradiologists. Of these 13 remnant necks, three were 3–5 mm in diameter and 10 <3 mm. Complete closure of the aneurysm was achieved in the remaining 64 aneurysms (83.1%). Based on these results, the diagnostic accuracy of each imaging technique was assessed. In this study, grades 1 and 2 were regarded as indicating complete closure of the aneurysm, while grades 3–5 indicated incomplete
Efficacy of 3D-CTA after clipping surgery
Recent reports have indicated that preoperative 3D-CTA can detect even small aneurysms around 1 mm in diameter.7, 16 After surgical clipping of cerebral aneurysm, the existence of the neck remnant must be evaluated. Presence of the neck remnant is associated with a potential risk of aneurysm regrowth,17, 18, 19 and the frequency of re-rupture is reported as 3.7–27.8%.18, 20, 21 In addition, even if the aneurysms were completely clipped, there would be risks for the development of de novo
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Cited by (34)
Assessment of long-term results of intracranial aneurysm clipping by means of computed tomography angiography
2013, Neurologia i Neurochirurgia PolskaCitation Excerpt :A few comparative studies on CTA and DSA for the evaluation of aneurysm clipping have been published over the last decade. The sensitivity and specificity of CTA for detecting neck remnants were reported to be 60–100% and 83–100%, respectively [5,6,33–36]. Along with the development of new CT devices, high accuracy of CTA has recently been reported [5,6,37].
Appearance and impact of post-operative intracranial clips and coils on whole-brain CT angiography and perfusion
2012, European Journal of RadiologyCitation Excerpt :The availability of 160 mm of craniocaudal coverage allows for whole-brain data acquisition that can be viewed as a time-resolved 4D CT DSA and may also be deconvolved to create whole-brain CT perfusion (CTP) maps. While CT DSA and CTP have been utilized to evaluate risk factors for delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage and for postoperative outcomes following coiling and clipping [7–11], whole-brain CT DSA has only recently been explored as an alternative to conventional angiography. As researchers and clinicians consider the viability of CT DSA and CTP for this purpose, it is important to quantify the effect vascular clips and endovascular coils have on the CTP values of regional cerebral blood volume (CBV), regional cerebral blood flow (CBF), mean transit time (MTT), and time to peak (TTP).
Applications of multislice CT angiography in the surgical clipping and endovascular coiling of intracranial aneurysms
2010, Journal of Biomedical ResearchClinical application of 16-row multislice computed tomographic angiography in the preoperative and postoperative evaluation of intracranial aneurysms for surgical clipping
2009, Surgical NeurologyCitation Excerpt :At some institutions, CTA has replaced DSA in the preoperative evaluations of patients with intracranial aneurysms [2,4,10,15]. At present, there have been numerous studies emphasizing the diagnostic accuracy of aneurysms by comparing multislice CTA with DSA [3,7,11,14,16]. Nevertheless, the purpose of our study was to evaluate the clinical application of 16-row multislice CTA in the preoperative and postoperative assessment of intracranial aneurysms for surgical clipping.