Reduced-dose CT protocol for the assessment of cerebral vasospasm.

INTRODUCTION: Despite the increased radiation dose, multimodal CT including noncontrast CT (NCT), CT angiography (CTA), and perfusion CT (PCT) remains a useful tool for the diagnosis of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). The aim of this study was to assess the radiation dose and the image quality between a standard-dose and a reduced-dose multimodal CT protocol. METHODS: The study group consisted of 26 aSAH patients with a suspicion of DCI on clinical examination and transcranial doppler. Two different CT protocols were used: a standard-dose protocol (NCT 120 kV, 350 mAs; CTA 100 kV, 250 mAs; PCT 80 kV, 200 mAs) from August 2011 to October 2013 (n = 13) and a reduced-dose protocol (NCT 100 kV, 400 mAs; CTA 100 kV, 220 mAs; PCT 80 kV, 180 mAs) from November 2013 to May 2014 (n = 13). Dose-length product (DLP), effective dose, volume CT dose index (CTDI), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and overall image quality were determined for each examination. RESULTS: The overall image quality was judged as good or excellent in all cases. The reduced-dose protocol allowed a 15 % decrease in both the median total DLP (2438 vs 2898 mGy cm, p < 0.0001) and the effective dose as well as a significant decrease in median CTDI of 23, 31, and 10 % for NCT, CTA, and CTP, respectively. This dose reduction did not result in significant alteration of SNR (except for NCT) or CNR between groups. CONCLUSION: The present study showed that the reduced-dose multimodal CT protocol enabled a significant reduction of radiation dose without image quality impairment.

A Pragmatic Randomized Trial Comparing Surgical Clipping and Endovascular Treatment of Unruptured Intracranial Aneurysms.

BACKGROUND AND PURPOSE: Surgical clipping and endovascular treatment are commonly used in patients with unruptured intracranial aneurysms. We compared the safety and efficacy of the 2 treatments in a randomized trial. MATERIALS AND METHODS: Clipping or endovascular treatments were randomly allocated to patients with one or more 3- to 25-mm unruptured intracranial aneurysms judged treatable both ways by participating physicians. The study hypothesized that clipping would decrease the incidence of treatment failure from 13% to 4%, a composite primary outcome defined as failure of aneurysm occlusion, intracranial hemorrhage during follow-up, or residual aneurysms at 1 year, as adjudicated by a core lab. Safety outcomes included new neurologic deficits following treatment, hospitalization of >5 days, and overall morbidity and mortality (mRS > 2) at 1 year. There was no blinding. RESULTS: Two hundred ninety-one patients were enrolled from 2010 to 2020 in 7 centers. The 1-year primary outcome, ascertainable in 290/291 (99%) patients, was reached in 13/142 (9%; 95% CI, 5%-15%) patients allocated to surgery and in 28/148 (19%; 95% CI, 13%-26%) patients allocated to endovascular treatments (relative risk: 2.07; 95% CI, 1.12-3.83; P = .021). Morbidity and mortality (mRS >2) at 1 year occurred in 3/143 and 3/148 (2%; 95% CI, 1%-6%) patients allocated to surgery and endovascular treatments, respectively. Neurologic deficits (32/143, 22%; 95% CI, 16%-30% versus 19/148, 12%; 95% CI, 8%-19%; relative risk: 1.74; 95% CI, 1.04-2.92; P = .04) and hospitalizations beyond 5 days (69/143, 48%; 95% CI, 40%-56% versus 12/148, 8%; 95% CI, 5%-14%; relative risk: 0.18; 95% CI, 0.11-0.31; P < .001) were more frequent after surgery. CONCLUSIONS: Surgical clipping is more effective than endovascular treatment of unruptured intracranial aneurysms in terms of the frequency of the primary outcome of treatment failure. Results were mainly driven by angiographic results at 1 year.

Trigeminal neuralgia related to arteriovenous malformation of the posterior fossa: three case reports and a review of the literature.

OBJECTIVE: To describe the rare association of trigeminal neuralgia (TGN) with a brain arteriovenous malformation (bAVM) of the posterior fossa. PATIENTS AND METHODS: This is a report of three patients presenting with TGN due to vascular compression by a bAVM of the posterior fossa, with emphasis on clinical presentation, diagnostic imaging, management and follow-up. Magnetic resonance imaging (MRI) was performed with sequences in thin slices in the same section plane using a 3D time of flight (TOF) and axial T2-weighted driven equilibrium (DRIVE) of the posterior fossa. RESULTS: No bleeding episodes were documented in the three patients. MRI and digital subtraction angiography (DSA) showed a posterior fossa bAVM with a nidus surrounding the trigeminal nerve, fed by arteries from the carotid and vertebrobasilar systems. Within a few days, medical treatment effectively alleviated the symptoms, with no more pain during follow-ups at 6, 10 and 18months. No invasive treatment was performed because the bAVMs were considered to have a low risk of bleeding. CONCLUSION: TGN related to a bAVM can mimic classical TGN. MRI and DSA are the imaging methods of choice. Medical treatment remains the first line of therapy, but if that fails, multimodal invasive treatment may be an alternative for pain relief.

Endovascular Stroke Therapy with a Novel 6-French Aspiration Catheter.

BACKGROUND AND PURPOSE: Direct thrombus aspiration is increasingly used as a first-line therapy in acute ischemic stroke with large vessel occlusion. We assessed the performance and safety of a novel aspiration catheter available: the 6-French AXS Catalyst catheter. MATERIALS AND METHODS: We conducted a cohort study from a prospective clinical registry of consecutive stroke patients treated by mechanical thrombectomy between March 2016 and July 2016. Baseline clinical and imaging characteristics, recanalization rates, complications, and clinical outcomes were analyzed. RESULTS: Among the 60 patients included, 30 were treated using aspiration alone, 14 were treated using aspiration and then stent retriever as a rescue therapy, and 16 were treated using aspiration combined with a stent retriever straightaway. Successful recanalization (mTICI2b/3) was achieved in 85% patients and functional independence in 48.3%. We observed one intracranial perforation and one vertebral artery dissection. Symptomatic intracranial hemorrhage occurred in 5% and mortality in 21.7%. CONCLUSION: Endovascular stroke therapy using the AXS Catalyst catheter seems safe and effective, with similar performance than other reperfusion catheters.

Minimally invasive approach for the treatment of lumbar epidural arteriovenous fistulas with intradural venous reflux.

BACKGROUND: Vascular lesions of the spinal cord are increasingly recognized. The most common types of these lesions are dural arteriovenous fistulas (AVFs) whereas, extradural AVFs are a very rare type of spinal AVF and can be associated with either extradural or intradural venous reflux. This results in neurological deficits through congestive or compressive myeloradiculopathy. These lesions must be treated to allow stabilization or improvement of neurologic status, either by endovascular therapy or microsurgical interruption. However, because some patients are not amenable to endovascular treatment, surgery is often warranted, which usually involves hemi- or bilateral laminectomy following a midline approach with bilateral muscle stripping. The main drawback of this procedure is directly related to the morbidity of the approach. Although, minimally invasive approaches are likely to overcome this drawback, there is a lack of reported experience supporting their use for treating spinal dural AVFs. CASE PRESENTATION: Two patients, aged 62 and 79 years old, presented with rapidly progressive myelopathy characterized by paraparesis and sphincter disturbance. Spinal magnetic resonance imaging showed spinal cord oedema with perimedullary flow voids in both cases. Digital subtraction angiography revealed extradural AVFs associated with perimedullary venous reflux. Endovascular therapy was not feasible. Both patients were treated with microsurgical interruption of the intradural vein through a non-expendable retractor. Complete exclusion was confirmed on postoperative angiography, resulting in resolution of spinal cord edema and improved neurological functional status at 2-year follow-up. CONCLUSION: The minimally invasive surgical treatment of spinal AVFs with epidural venous reflux is safe and effective. This approach is a valuable alternative to endovascular therapy and the standard open microsurgical approach.

A dissecting aneurysm of a basilar perforating artery.

We report an additional case of a ruptured basilar trunk perforator aneurysm, for which an endovascular treatment was initially planned, but aborted due to the spontaneous regression of the aneurysm. Thus, a conservative management consisting on a close follow-up was decided that confirmed the favorable radiological outcome. Spontaneous regression of such aneurysm should be well-known by neurosurgeons and neuroradiologists in order to prevent the potential iatrogenic effects of the related treatment modalities.

Inter- and Intrarater Agreement on the Outcome of Endovascular Treatment of Aneurysms Using MRA.

BACKGROUND AND PURPOSE: Patients treated with coiling are often followed by MR angiography. Our objective was to assess the inter- and intraobserver agreement in diagnosing aneurysm remnants and recurrences by using multimodality imaging, including TOF MRA. MATERIALS AND METHODS: A portfolio composed of 120 selected images from 56 patients was sent to 15 neuroradiologists from 10 institutions. For each case, raters were asked to classify angiographic results (3 classes) of 2 studies (32 MRA-MRA and 24 DSA-MRA pairs) and to provide a final judgment regarding the presence of a recurrence (no, minor, major). Six raters were asked to independently review the portfolio twice. A second study, restricted to 4 raters having full access to all images, was designed to validate the results of the electronic survey. RESULTS: The proportion of cases judged to have a major recurrence varied between 16.1% and 71.4% (mean, 35.0% ± 12.7%). There was moderate agreement overall (κ = 0.474 ± 0.009), increasing to nearly substantial (κ = 0.581 ± 0.014) when the judgment was dichotomized (presence or absence of a major recurrence). Agreement on cases followed-up by MRA-MRA was similarly substantial (κ = 0.601 ± 0.018). The intrarater agreement varied between fair (κ = 0.257 ± 0.093) and substantial (κ= 0.699 ± 0.084), improving with a dichotomized judgment concerning MRA-MRA comparisons. Agreement was no better when raters had access to all images. CONCLUSIONS: There is an important variability in the assessment of angiographic outcomes of endovascular treatments. Agreement on the presence of a major recurrence when comparing 2 MRA studies or the MRA with the last catheter angiographic study can be substantial.

[Multifocal motor neuropathy after administration of gangliosides]. / Neuropatía motora multifocal tras la administración de gangliósidos.

A case of a 38 years-old male with motor neuropathy with multifocal conduction blocks following the administration of ganglioside therapy is reported. There was generalized weakness without areflexia and normal parameters of the spinal fluid, including protein values. Electrophysiological data showed multiple conduction blocks with normal nerve conduction velocities. Antibodies against asialo-GM1 gangliosides were present in the cerebrospinal fluid. There could be a relationship between the ganglioside administration and the development of an immune-mediated neuropathy. Several cases of demyelinating polyradiculoneuritis after ganglioside treatment have been reported. If this association is confirmed, the apparent lack of toxicity of gangliosides should be reconsidered.

Inter- and intraobserver agreement in scoring angiographic results of intra-arterial stroke therapy.

BACKGROUND AND PURPOSE: Angiographic results are commonly used as surrogate markers of the success of intra-arterial therapies for acute stroke. Inter- and intraobserver agreement in judging angiographic results remain poorly characterized. Our goal was to assess 2 commonly used revascularization scales. MATERIALS AND METHODS: A portfolio of 148 pre- and post treatment images of 37 cases of proximal anterior circulation occlusions was electronically sent to 12 expert observers who were asked to grade treatment outcomes according to recanalization (of arterial occlusive lesion) or reperfusion (TICI) scales. Three expert observers had to score treatment outcomes by using a similar portfolio of 32 patients or when they had full access to all angiographic data, twice for each method 3-12 months apart. Results were analyzed by using κ statistics. RESULTS: Agreement among 9 responding observers was moderate for both the TICI (κ = 0.45 ± 0.01) and arterial occlusive lesion (κ = 0.39 ± 0.16) scales. Agreement was similar (moderate) when 3 observers had access to a portfolio (κ = 0.59 ± 0.06 and 0.49 ± 0.07, respectively) or to the full angiographic data (κ = 0.54 ± 0.06 and 0.59 ± 0.07, respectively). Intraobserver agreement was "fair to moderate" for both methods. Interobserver agreement became "substantial" (>0.6) when outcomes were dichotomized into "success" (TICI 2b, 3; arterial occlusive lesion II, III or "failure"; the results were judged more favorably when the arterial occlusive lesion rather than the TICI scale was used. CONCLUSIONS: There is an important variability in the assessment of angiographic outcomes of endovascular treatments, invalidating comparisons among publications. A simple dichotomous judgment can be used as a surrogate outcome when treatments are assessed by the same observers in randomized trials.

Mechanical thrombectomy in acute stroke: prospective pilot trial of the solitaire FR device while under conscious sedation.

BACKGROUND AND PURPOSE: The best approach between general anesthesia and conscious sedation to perform mechanical thrombectomy remains unknown. The goal of our study was to evaluate the feasibility, safety, and efficacy of mechanical thrombectomy under conscious sedation in patients with acute ischemic stroke, using the Solitaire FR device, in a prospective, single-center, single-arm study. MATERIALS AND METHODS: The study included consecutive patients with acute ischemic stroke due to a large artery occlusion within 6 hours of symptom onset for the anterior circulation, and within 24 hours for the posterior circulation. After intravenous thrombolysis (when no contraindications), thrombectomy was performed with the Solitaire device in patients under conscious sedation. Primary efficacy and safety end points were good functional outcome (mRS ≤2) at 3 months and mortality at 3 months. Secondary end points were recanalization (TICI ≥2) and failure rate. RESULTS: From May 2010 to July 2011, 36 patients were treated. Median baseline NIHSS score was 17.5. The occlusion site was MCA in 21 patients (58.4%), ICA-MCA tandem occlusion in 9 patients (25.0%), terminal ICA in 2 patients (5.5%), and basilar artery in 4 patients (11.1%). Twenty-three patients (63.9%) received intravenous thrombolysis. Superselective catheterization of the occluded vessel was not feasible in 5/36 cases (13.9%). Successful revascularization was achieved in 28/36 patients (77.8%). After 3 months, 22 patients (61.1%) showed good functional outcome (mRS ≤2) and the median NIHSS score was 8.5. Overall mortality rate at 3 months was 22.2% (8/36). CONCLUSIONS: In acute ischemic stroke, mechanical thrombectomy while under conscious sedation is feasible in a large percentage of cases (86.1%) and is associated with a short procedure delay and a high percentage of good functional outcomes at 3 months (61.1%).

[Idiopathic cervical plexopathy]. / Plexopatía cervical idiopática.

We describe a 26 year-old woman with cervical plexopathy with damage of left superficial or cutaneous branches, and left cervical sensory dorsal rami. Picture began acutely and vanished few days later. We ruled out known etiologies like traumatisms, tumours and surgical and anaesthetic complicated procedures, therefore the patient suffered an idiopathic cervical plexopathy. We hypothesize two possibilities for this clinical picture: an autoimmune reaction or a muscular entrapment.