Applications of the Columbus steerable guidewire

The Columbus steerable guidewire (Rapid Medical, Israel) is a 0.014 inch guidewire with a remotely controlled deflectable tip intended for neuronavigational purposes. 1 The tip can be shaped by pulling or pushing the handle. Pulling the handle decreases the radius (from 4 mm to 2 mm) and curves the tip, while pushing the handle increases the curvature radius and straightens the tip until it bends in the opposite direction. The amount of deflection is at the discretion of the operator. Video 1 The response of the Columbus guidewire to rotational movements is inferior to that of standard wires, and the tip is very soft and malleable but brings great support when bent. We present two cases where the Columbus guidewire was used. In the first case, the Columbus enabled us to probe a posterior cerebral artery arising from a giant basilar tip aneurysm without wall contact. In the second case, the Columbus was used as a secondary wire to help cannulate the pericallosal artery in a patient with a recurrent anterior complex aneurysm; this subsequently permitted successful stent-assisted coiling of the aneurysm.Video 1

A risk-adjusted and anatomically stratified cohort comparison study of open surgery, endovascular techniques and medical management for juxtarenal aortic aneurysms—the UK COMPlex AneurySm Study (UK-COMPASS): a study protocol

IntroductionIn one-third of all abdominal aortic aneurysms (AAAs), the aneurysm neck is short (juxtarenal) or shows other adverse anatomical features rendering operations more complex, hazardous and expensive. Surgical options include open surgical repair and endovascular aneurysm repair (EVAR) techniques including fenestrated EVAR, EVAR with adjuncts (chimneys/endoanchors) and off-label standard EVAR. The aim of the UK COMPlex AneurySm Study (UK-COMPASS) is to answer the research question identified by the National Institute for Health Research Health Technology Assessment (NIHR HTA) Programme: ‘What is the clinical and cost-effectiveness of strategies for the management of juxtarenal AAA, including fenestrated endovascular repair?’Methods and analysisUK-COMPASS is a cohort study comparing clinical and cost-effectiveness of different strategies used to manage complex AAAs with stratification of physiological fitness and anatomical complexity, with statistical correction for baseline risk and indication biases. There are two data streams. First, a stream of routinely collected data from Hospital Episode Statistics and National Vascular Registry (NVR). Preoperative CT scans of all patients who underwent elective AAA repair in England between 1 November 2017 and 31 October 2019 are subjected to Corelab analysis to accurately identify and include every complex aneurysm treated. Second, a site-reported data stream regarding quality of life and treatment costs from prospectively recruited patients across England. Site recruitment also includes patients with complex aneurysms larger than 55 mm diameter in whom an operation is deferred (medical management). The primary outcome measure is perioperative all-cause mortality. Follow-up will be to a median of 5 years.Ethics and disseminationThe study has received full regulatory approvals from a Research Ethics Committee, the Confidentiality Advisory Group and the Health Research Authority. Data sharing agreements are in place with National Health Service Digital and the NVR. Dissemination will be via NIHR HTA reporting, peer-reviewed journals and conferences.Trial registration numberISRCTN85731188.

Comprehensive review of the recent advances in devices for endovascular treatment of complex brain aneurysms

The International Subarachnoid Aneurysm Trial (ISAT) showed superiority for endovascular treatment of ruptured aneurysms and technology has since moved on rapidly. Many approaches and technology now exist for the endovascular management of ruptured and unruptured intracranial aneurysms, which reflects their varied nature – there is no one-size-fits-all technique. We aim to provide an overview of the various classes of device and the major developments over the past decade. Coiling is the oldest of the technology and continues to demonstrate high levels of occlusion and acceptable risks, making it the default treatment choice, particularly in the acutely ruptured aneurysm setting. Advances on coiling include the use of adjuncts such as balloons, stents and fully retrievable temporary neck-bridging devices, which have facilitated the treatment of more complex aneurysms. Flow divertors have also revolutionised complex aneurysm treatment with small added risk in acute aneurysm treatment and seek to remodel the aneurysm–vessel interface without accessing the aneurysm sac. The latest development and most promising avenue appears to be intrasaccular flow disrupting devices like WEB, Contour and Neqstent that provide excellent opportunities to treat wide neck complex aneurysm with minimal mortality and morbidity and good occlusion rates and may in future replace a significant number of stent-assisted coiling too.

Clip Reconstruction of a Previously Leaked Large Complex Posterior Communicating Segment Aneurysm with Extradural Anterior Clinoidectomy

Fusiform or near-fusiform aneurysms that involve the long segment of the supraclinoid internal carotid artery (ICA) pose significant challenges to neurovascular surgeons. Involvement of the origin of vital branching arteries in this segment may preclude safe treatment with flow diverting stents. In addition, clip reconstruction may also not be possible in this region due to entire or near-entire involvement of the circumference of the ICA (Fig. 1). In this video article, we present a case of a complex and previously leaked, (visualized with hemosiderin) aneurysm of the posterior communicating segment of the ICA, in a 60-year-old female. Multiple complexities made this aneurysm challenging to treat. These included (1) a 270-degree encirclement of the ICA with multiple lobulations that left only a small section of nondiseased vessel wall, (2) a relatively short segment of the supraclinoidal ICA that made proximal control challenging thus requiring an extradural anterior clinoidectomy, (3) a fetal posterior communicating artery that originated immediately proximal to the beginning of the aneurysm, and lastly, (4) an anterior choroidal artery that was firmly adherent over the aneurysm dome. In this video, we present the microsurgical steps for dealing with this complex aneurysm, including extradural clinoidectomy and clip reconstruction (Fig. 2). Postoperatively, the patient woke up without any deficits. Angiography showed complete obliteration of the aneurysm.The link to the video can be found at: https://youtu.be/C3Vc0maWChc.

When Is Diagnostic Subtraction Angiography Indicated Before Clipping of Unruptured and Ruptured Intracranial Aneurysms? An International Survey of Current Practice

Introduction: The goal of this survey is to investigate the indications for preoperative digital subtraction angiography (DSA) before clipping of ruptured and unruptured intracranial aneurysms in an international panel of neurovascular specialists.Methods: An anonymous survey of 23 multiple-choice questions relating to indications for DSA before clipping of an intracranial aneurysm was distributed to the international panel of attendees of the European-Japanese Cerebrovascular Congress (EJCVC), which took place in Milan, Italy on 7–9 June 2018. The survey was collected during the same conference. Descriptive statistics were used to analyze the data.Results: A total of 93 surveys were distributed, and 67 (72%) completed surveys were returned by responders from 13 different countries. Eighty-five percent of all responders were neurosurgeons. For unruptured and ruptured middle cerebral artery (MCA) aneurysms without life-threatening hematoma, approximately 60% of responders perform surgery without preoperative DSA. For aneurysms in other locations than MCA, microsurgery is done without preoperative DSA in 68% of unruptured and in 73% of ruptured cases. In cases of ruptured MCA or ruptured non-MCA aneurysms with life-threatening hematoma, surgery is performed without DSA in 97% and 96% of patients, respectively. Factors which lead to preoperative DSA being performed were: aneurysmal shape (fusiform, dissecting), etiology (infectious), size (>25 mm), possible presence of perforators or efferent vessels arising from the aneurysm, intra-aneurysmal thrombus, previous treatment, location (posterior circulation and paraclinoid aneurysm) and flow-replacement bypass contemplated for final aneurysm treatment. These are all factors that qualify an aneurysm as a complex aneurysm.Conclusion: There is still a high variability in the surgeons’ preoperative workup regarding the indication for DSA before clipping of ruptured and unruptured intracranial aneurysms, except for ruptured aneurysms with life-threatening hematoma. There is a general consensus among cerebrovascular specialists that any angioanatomical feature indicating a complex aneurysm should lead to a more detailed workup including preoperative DSA.

Quantifying asymmetry of anterior cerebral arteries as a predictor of anterior communicating artery complex aneurysm

ObjectivesThe aim of this study was to establish an anatomical index for early prediction of the risk of development of aneurysms in anterior communicating arterial complex (AcomAC). The asymmetric diameter of one anterior cerebral artery (ACA) to other could alter haemodynamics and may contribute to formation of aneurysms in AcomAC and be a reliable predictor of the risk of development of aneurysms.Design and settingThis is a retrospective, observational and quantitative study, which used cerebral computed tomography angiography (CCTA) scans in South Australia.ParticipantsCCTA scans of 166 adult patients of both sexes were studied.Main outcome measuresThe internal diameters of the proximal segments of ACAs (A1s) were measured. Position and presence or absence of aneurysms in AcomAC were determined. The ratio of A1 diameters was taken as a measure of A1 asymmetry.ResultsThe ratio of diameters of A1s correlated with the occurrence of AcomAC aneurysms. The risk of development of aneurysms in AcomAC was much greater (80%, OR=47.3) when one A1 segment’s radius was at least 50% larger (ie, 2.25 times cross-sectional area) than the other.ConclusionThe general information on asymmetric A1 has been published previously. The present findings have significant contribution since the A1s asymmetry ratios have been categorised in ascending order and matched with the presence of AcomAC aneurysms. The asymmetry ratio of the A1 is a good predictor for the development of AcomAC aneurysms. Reconstruction of the asymmetric A1 could be done if the technology gets advanced.

Review of Type III Endoleaks

Endoleak remains a significant challenge to endovascular aneurysm repair, particularly as evolving techniques and devices have allowed treatment of increasingly complex aneurysm anatomy with increasing number of device components. Intervention is recommended for both type I and III endoleaks due to their risk of rupture, and endovascular techniques are the favored modality with placement of a bridging endograft over the endoleak defect. Conversion to open surgical repair remains the definitive option in cases where less invasive methods have failed or are precluded. In this article, the authors review evidence on the etiology, incidence, diagnosis, and current techniques for type III endoleak management.