Maria Cortes

SILK flow diverter for complex intracranial aneurysms: a Canadian registry

Introduction The SILK flow diverter (SFD) is used for the treatment of complex intracranial aneurysms. Small case series have been reported in the literature but few studies with a large number of patients have been published. We present our experience with the SFD for the treatment of intracranial aneurysms in Canada. Methods Centers across Canada using SFDs were contacted to fill out a case report form for patients treated with an SFD in their center. Individual centers were responsible for approval from their ethics committee. Image analysis was performed by individual operators. The case report forms were collected and the final analysis was performed. Results A total of 92 patients were treated with SFDs in eight centers in Canada between January 2009 and August 2013. The aneurysms were located in the posterior circulation in 16 patients and in the anterior circulation in 76 patients. Most aneurysms (75%) were saccular in shape; 22% were fusiform and 3% were blister aneurysms. The size of the aneurysms varied from 2 to 60 mm with the neck varying from 2 to 60 mm. Perioperative morbidity and mortality were 8.7% and 2.2%, respectively. At the last available follow-up, 83.1% of the aneurysms were either completely or near-completely occluded. The rate of complications was higher for fusiform aneurysms (p<0.001). Conclusions The SFD appears to be an important tool for the treatment of complex intracranial aneurysms. Treatment outcomes and complication rates remain a problem, but should be considered in the context of available alternative interventions. Ongoing analysis of flow-diverting stents for radiographic and clinical performance is required.

Imaging pattern of calvarial lesions in adults

Calvarial lesions often present themselves as clinically silent findings on skull radiographs or as palpable masses that may cause localized pain or soreness. This review aims to explore the radiographic, computed tomography (CT), and magnetic resonance imaging (MRI) characteristics of calvarial neoplastic, inflammatory, and congenital lesions that are common in adults in order to facilitate a structured approach to their diagnosis and limit the differential diagnosis. In addition to reviewing the literature, we reviewed the records of 141 patients of the Montreal Neurological Institute and Hospital with radiologically documented calvarial lesions between 2001 and June 2009. CT is ideal for detecting bony lesions and is helpful in precisely localizing a lesion pre-surgically. MRI is best at identifying intradiploic lesions before they affect the cortical tables and is able to establish extraosseous involvement, especially when paramagnetic contrast is employed.

Canadian Registry of LVIS Jr for Treatment of Intracranial Aneurysms (CaRLA)

Introduction Stents reduce the rate of angiographic recurrence of intracranial aneurysms. The newest stent for intracranial use is the Low-profile Visible Intraluminal Support device (LVIS Jr). Objective To assess the efficacy of the new stent in a multicenter retrospective registry. Materials and method Centers across Canada using LVIS Jr were contacted and asked to participate in a retrospective registry of consecutive patients treated with LVIS Jr for intracranial aneurysms between January 2013 and July 2015. Results A total of 102 patients, with saccular aneurysms in 100 patients (72 women; age range 21–78 years; mean 56.0 years; median 57.5 years) were treated with a LVIS Jr stent. The mean maximum diameter of the dome and neck of the aneurysm and dome to neck ratios were 8.3 mm±7.7 mm, 4.4 mm±1.9 mm, and 1.86±1.22, respectively. Angiographic complications arose in 23 patients, clinical complications in 9 patients, and only 3% of permanent neurological deficits occurred. Death occurred in 1 patient, unrelated to the stent. The ruptured status of the aneurysms (OR=3.29; p=0.046) and use of LVIS Jr for bailout (OR=2.54; p=0.053) showed a trend towards significant association with higher angiographic complications. At the last available follow-up, 68 class I, 20 class II, and 12 class III results were seen. Conclusions The LVIS Jr stent is a safe and effective device for stent-assisted coiling, with 3% permanent neurological complications. Stent-assisted coiling continues to be technically challenging in cases of ruptured aneurysms and bailout situations.

Extensive bilateral arteriovenous malformations of the mandible successfully controlled by combined endovascular and transcutaneous angio-embolization: case report and review of the literature.

We report a unique case of extensive bilateral arteriovenous malformation (AVMs) in a childs mandible, discuss treatment options and review literature. A healthy 8 year-old girl presented with bright blood of unknown source found on her pillow. Three large AVMs involving the symphyseal region and bilateral mandibular bodies were found on angiography. Due to the extent of surgical resection required, the patient underwent a series of endovascular and transcutaneous angio-embolization. In cases of extensive intraosseous AVMs, serial embolization procedures can be successful in controlling episodes of hemorrhage and allow for bone remineralization. A multidisciplinary approach by otolaryngologists and neurointerventional radiologists can optimize the results.

Re-Growth of a Posterior Inferior Cerebellar Artery Aneurysm after Resection of the Associated Posterior Fossa Arteriovenous Malformation

Arteriovenous malformation (AVM)-related aneurysms have been described in the literature. Their behavior varies based on their location in relation to and the activity of the shunting through the index AVM. The intuitive expectation supported by numerous reports is that these aneurysms should regress if the AVM is excluded from the circulation. We describe a case of 46-year-old man who presented with a posterior fossa AVM with an aneurysm on the posterior inferior cerebellar artery feeding the AVM. The nidus of the AVM was successfully excluded by glue embolization, with initial regression of the PICA aneurysm on serial imaging. Five years after the endovascular treatment, the aneurysm showed significant re-growth necessitating endovascular coiling. This case presents the re-growth of an AVM-related aneurysm and emphasizes the importance of long-term follow-up of such aneurysms even if the AVM is completely excluded.

Intraventricular localization of an anaplastic oligodedendroglioma: a rare event.

CASE DESCRIPTION In 2004, a 24-year-old woman presented initially with seizures and she was diagnosed, in another centre, with a right frontal space occupying lesion. she underwent a right frontal craniotomy and a subtotal resection of the lesion. the pathology demonstrated an anaplastic oligodendroglioma (combined allelic losses for 1p and 19q chromosomes, MGMt promoter methylated). the tumour recurred in 2007 and the lesion was again subtotally resected and treated with chemotherapy and temozolomide. In spite of the treatment, the lesion continued to increase in size (Figure 1) and the patient was referred to our institution

The insidious appearance of the dissecting aneurysm: Imaging findings and related pathophysiology. A report of two cases

Intracranial dissecting aneurysms have been frequently reported to present with fairly challenging and time-variable imaging findings that can be mostly explained by the pathological mechanisms that underline the dissection. We present two cases of spontaneous dissecting aneurysm of the supraclinoid ICA, both clinically presenting with SAH, but characterized by different progression of clinical symptoms and imaging. However, in both cases an outpouch and a mild fusiform dilation of the supraclinoid ICA was present in the initial CTA performed after the occurrence of symptoms. These findings were well depicted by the MPR reformats performed retrospectively. We postulate that this finding may represent the point of initial transmural dissection and we recommend that careful analysis of the CTA MRP reformatted images should be performed in order to detect this finding promptly.

Assessment of clot length with multiphase CT angiography in patients with acute ischemic stroke

Introduction Existing stroke literature demonstrates that rapid recanalization of vessels improves long-term prognosis after acute ischemic stroke. However, further optimization of the speed of the thrombectomy procedure, used to recanalize a blocked vessel, is limited by our minimal knowledge of the clot dimensions pre-procedure. Knowing the clot dimensions would allow planning of the thrombectomy procedure with the appropriate size and length of stent retriever, and determination of the correct site of the stent deployment ensuring total coverage of the clot by the stent retriever. Methods We performed a feasibility study to assess if multiphase computed tomography angiography (mCTA) can be used to estimate clot length by comparing CTA imaging data with imaging data obtained from conventional digital subtraction angiography (DSA). A retrospective chart review was performed of patients with clots in the proximal middle cerebral artery and adequate collateral circulation, who underwent both mCTA and DSA. Results Clot length was not significantly different on 3D mCTA versus mCTA MIPs, nor was it significantly different on MIP mCTA versus DSA. Pathological evidence also supported our ability to measure clot length on mCTA. Conclusions We suggest that mCTA is a reliable and valid measure of clot length in acute ischemic stroke patients.

Inflow Angle of Small Paraophthalmic Aneurysms Is a Determinant of Adjacent Sphenoid Bone Remodeling

Objective Large internal carotid artery aneurysms can cause remodeling of the sphenoid bone with subsequent hemorrhage into the sinus. No reports have demonstrated small unruptured lesions causing similar bone remodeling. The purpose of this study was to demonstrate our experience with small unruptured paraophthalmic aneurysms causing sphenoid bone remodeling, specifically when the optimal aneurysm inflow angle is present. Methods We searched our database for computed tomography angiography studies of small paraophthalmic aneurysms and assessed adjacent sphenoid bone remodeling and inflow angle. Results We found that aneurysms causing sphenoid remodeling represent 19.51% of all small paraophthalmic aneurysms at our institution and that the average inflow angle for these aneurysms was 94.38 degrees, significantly greater than for those not causing remodeling. Conclusions Our findings add support to using computed tomography angiography in the follow-up of aneurysms to assess surrounding bone changes and to the development of a more evidence-based approach in the management of small paraophthalmic aneurysms, which currently may be managed conservatively.

320-Row Multidetector CT Angiography in the Detection of Critical Cerebrovascular Anomalies

BACKGROUND The acquisition of a new 320-row multidetector computed tomography angiography (CTA) scanner at the Montreal Neurological Institute and Hospital has provided higher quality imaging with less radiation exposure and shorter time of acquisition. However, its reliability has not been fully proven in critical vascular lesions when it comes to replacing a more invasive examination such as cerebral angiography. We wished to validate the accuracy of this equipment to investigate four common indications for patients to undergo conventional digital subtraction angiography: subarachnoid hemorrhage, vasospasm, unusual intracerebral hemorrhage, and unruptured aneurysm. METHODS Radiological reports and relevant imaging from 82 consecutive subjects who underwent a 320-row multidetector CTA followed by cerebral angiography from February 2010 to February 2014 were retrospectively analysed. A total of 102 cerebrovascular anomalies were found. Reports from both imaging modalities were compared to determine the diagnostic accuracy of CTA. RESULTS The overall sensitivity and specificity of 320-row multidetector CTA for detecting cerebrovascular abnormalities were, respectively, 97.60% and 63.20%. Similar results were obtained for all four categories of clinical indications. CONCLUSION Results obtained from CTA were consistent with those obtained on digital subtraction angiography regardless of the vascular pathology. To our knowledge, this study is the first validating the accuracy of 320-row CTA in diagnosing critical cerebrovascular lesions.