De novo distal middle cerebral artery aneurysm post-excision of intracerebral arteriovenous malformation in an 8-year old.

Cerebral arteriovenous malformations (AVMs) are frequently associated with concurrent aneurysms. These aneurysms are commonly haemodynamically related to the AVM and can be classified into extranidal or intranidal in reference to the AVM nidus. An aneurysm arising from an artery that does not angiographically contribute to the blood flow to the AVM is uncommon. A distal middle cerebral artery (dMCA) aneurysm itself is also a rare presentation, especially in paediatric population. We present a rare case of dMCA aneurysm that was noted after successful surgical management of a ruptured AVM in an 8-year-old child and its management. BACKGROUND: About 10-30% of patients with cerebral arteriovenous malformation (AVM) have an associated artery aneurysm. The majority of these aneurysms are flow-related to the malformation. These aneurysms can be classified into extranidal or intranidal in reference to the AVM nidus Rammos et al Am J Neuroradiol 37:1966-1971, [1]. An aneurysm arising from a different artery that does not angiographically contribute to the blood flow associated with the AVM is less common and would generally be regarded as unrelated to the AVM. Distal cerebral artery aneurysm itself is also a rare presentation, comprising of 1-7% of all middle cerebral artery aneurysm. In children, mycotic infection and dissection are the two most common causes for aneurysm in this location. Unlike in adults, berry aneurysms are uncommon in children. We describe a young patient who was found to have distal middle cerebral artery (dMCA) aneurysm in follow-up DSA (Digital Subtraction Angiogram) after the initial successful surgical treatment for a cerebral frontal AVM. In this particular case, endovascular repair is thought to be the best strategy to treat the aneurysm. However, there still remains a lack of consensus of the best management strategy (surgery or endovascular) in treating flow-related aneurysms in general. This is usually based on an individual case scenario and the treatment is tailored depending on various factors including the expertise of the treating team.

The pEGASUS-HPC stent system for stent-assisted coiling of cerebral aneurysms: a multicenter case series.

BACKGROUND: Stent-assisted coiling (SAC) is a well-established method for treatment of wide-necked intracranial aneurysms. In this multicenter, retrospective case series we evaluated SAC with a new low-profile, laser-cut stent with an antithrombogenic hydrophilic polymer coating (pEGASUS-HPC) for the treatment of intracranial aneurysms. METHODS: Patients treated with pEGASUS-HPC SAC for one or more intracranial aneurysms were retrospectively included. Clinical, imaging, and procedural parameters as well as clinical and imaging follow-up data were recorded. RESULTS: We treated 53 aneurysms in 52 patients in six neurovascular centers between August 2021 and November 2022. Thirty-seven patients (69.8%) were female. Mean age was 57 (±11.7) years. Twenty-nine patients were treated electively, 23 in the acute phase (22 with aneurysmal subarachnoid hemorrhage (SAH), and 1 with a partially thrombosed aneurysm causing ischemic events). One intraprocedural thromboembolic event and three postprocedural ischemic complications occurred in two (8.7 %) of the SAH patients and in one of the elective patients (3.45%). Overall aneurysm occlusion was Raymond Roy (RR) I in 36 (69.2%), RR II in 9, and RR III in 9 cases. Follow-up imaging was available for 23 patients after an average of 147.7 (±59.6) days demonstrating RR I occlusion in 22 (95.5%) and RR II in 1 patient. CONCLUSION: SAC with the pEGASUS-HPC stent system demonstrates rates of periprocedural safety and effectiveness that are comparable with previously reported series for stent-assisted coil embolization.

WEB vs coiling in ruptured aneurysms: A propensity score matched comparison of safety and efficacy.

BACKGROUND: We aim to compare the safety and efficacy of WEB with coiling for acutely ruptured aneurysms.METHODS: All consecutive ruptured aneurysms with width suitable for WEB (2-10 mm) treated over 5 years (1/1/2015 to 31/12/2019) were included. We recorded WFNS, Fisher grade, patient demographics and aneurysm characteristics (size, location, D/W and aspect ratio, lobulation). Primary endpoints were mRS status at 3 months, aneurysm occlusion on latest available imaging follow-up, retreatment rate and procedural complications. We applied propensity score matching using aneurysm morphology (size, D/N ratio, ASPECT ratio and lobulation) to optimise matching for WEB versus coil comparison and minimise the effects of confounding. RESULT: A total of 493 patients were identified, 97 treated with the WEB device. 1:1 propensity score matching was used to establish a matched group of 97 patients treated with coiling. The WEB arm showed 3% procedural complication rate, with no haemorrhagic complications and use of adjunctive device in 4%. Satisfactory occlusion on follow-up (mean 14 months) was 79%, with 19% retreatment rate. The coil arm had 8% complication rate, with use of an adjunctive device in 52% of cases (balloon 44%, stent 8%). Satisfactory occlusion on follow-up (mean 22 months) was 90%, with 8% retreatment rate. CONCLUSION: Treatment of ruptured wide-necked bifurcation aneurysms with WEB has a lower complication rate than coiling with high rate of satisfactory occlusion. However, there was a higher retreatment rate when compared with patients treated with coiling. An adjunct device (balloon or stent), was used in over 50% of aneurysms in the coiling group.

pCONUS 2 and pCONUS 2-HPC in the treatment of wide-necked intracranial aneurysms: Multicentre UK experience.

BACKGROUND/PURPOSE: pCONUS 2 and pCONUS 2-HPC are neck-bridging devices that provide coiling support in the endovascular treatment of wide-necked intracranial aneurysms. To date, limited multicentre data has been published. This study provides the first pooled data from multiple UK centres regarding outcomes for these devices covering the periprocedural period to 6-month follow-up. MATERIALS/METHODS: This retrospective, single-arm study assessed 65 patients treated over 3 years from the time of procedure to 6 months post-procedure across four UK centres. Data collected included patient demographics, aneurysm characteristics and antiplatelet regimens. Outcome measures were angiographic results and procedure-related complications from the immediate periprocedural period to 6-month follow-up. RESULTS: Fifty-four unruptured (83.1%) and 11 ruptured (16.9%) aneurysms were treated. Fifty-five aneurysms were located in the anterior circulation (87.7%). There were four device-related intraprocedural complications: three cases of asymptomatic, temporary thrombus formation and one mortality associated with branch vessel occlusion and aneurysm re-bleeding in a ruptured case. There were no post-procedural device-related complications. Satisfactory occlusion was achieved in 58/65 procedures (89.2%) at time of treatment and in 44/60 (73.3%) at 6 months. Satisfactory occlusion correlated with aneurysm size and coiling packing density. Retreatment was required for five unruptured cases (7.7%) and was straightforward with the device in situ. CONCLUSION: pCONUS 2 and pCONUS 2-HPC have good short-term safety profiles. The use of pCONUS 2-HPC in the acute treatment of ruptured aneurysms with postprocedural SAPT is feasible. The devices have an intraprocedural complication rate of 4/65 (6.2%) across multiple UK centres, including a single death (1.5%).

Safety of dual antiplatelet therapy using aspirin and low-dose Prasugrel with platelet reactivity testing in flow diverter treatment of intracranial aneurysms.

BACKGROUND: Dual antiplatelet therapy (DAPT) is standard care for intracranial stenting to prevent thrombotic complications. Clopidogrel resistance has resulted in patients receiving newer P2Y12 inhibitors like Prasugrel, which may reduce thrombotic complications but could increase haemorrhagic complications. This study, utilising platelet reactivity testing, compared thrombotic and haemorrhagic complications associated with Clopidogrel or 20 mg Prasugrel loading in patients treated with flow diverters (FD) for intracranial aneurysms. METHODS: We retrospectively analysed prospectively collected data from 225 consecutive FD procedures. All patients received aspirin. 147 cases received Clopidogrel and 82 received Prasugrel. All patients had VerifyNow testing before the procedure. RESULTS: P2Y12 non-responders were significantly more likely to have thrombotic complications than responders and hyper-responders (7% vs. 2%, p = 0.01). Low-dose Prasugrel resulted in a significantly lower rate of non-responders when compared with Clopidogrel (7% vs. 25%, p < 0.01). We found no statistically significant difference in rates of haemorrhage between the Clopidogrel and Prasugrel groups (2.4% vs. 3.9%, p = 0.47). There were 12 complications (≤7 days) in the Clopidogrel group versus 6 in the Prasugrel group (9% vs. 7.8%, respectively, p = 0.91) and a non-significant reduction in thrombotic complications in the Prasugrel group (5.2% vs. 3.9%, p = 0.88). No significant difference was shown in long-term complications between the groups (p = 0.33). CONCLUSION: These results support the use of platelet reactivity testing and the safety of low-dose Prasugrel for FD treatment of intracranial aneurysms.

Coating (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) study. The first randomized controlled trial evaluating a coated flow diverter (p64 MW HPC): study design.

BACKGROUND: Due to its high efficacy, flow diversion is increasingly used in the management of unruptured and recanalized aneurysms. Because of the need for perioperative dual antiplatelet treatment (DAPT), flow diversion is not indicated for the treatment of ruptured aneurysms. To overcome this major limitation, surface modification-'coating'-of flow diverters has been developed to reduce platelet aggregation on the implanted device, reduce thromboembolic complications, and facilitate the use of coated flow diverter treatment in patients with single antiplatelet treatment (SAPT). COATING (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) is a prospective, randomized, multicenter trial that aims to determine whether the use of the coated flow diverter p64 MW HPC under SAPT is non-inferior (or even superior) to the use of the bare flow diverter p64 MW under DAPT in relation to thromboembolic and hemorrhagic complications. METHODS: Patients with unruptured or recanalized aneurysms for which endovascular treatment with a flow diverter is indicated will be enrolled and randomly assigned on a 1:1 ratio to one of two treatment groups: p64 MW HPC with SAPT or p64 MW with DAPT. RESULTS: The primary endpoint is the number of diffusion-weighted imaging lesions visualized via MRI assessed within 48 hours (±24 hours) of the index procedure. Secondary primary endpoints are comparing safety and efficacy in both arms. CONCLUSIONS: This randomized controlled trial is the first to directly compare safety and efficacy of coated flow diverters under SAPT with bare flow diverters under DAPT. TRIAL REGISTRATION NUMBER: http://clinicaltrials.gov/ - NCT04870047.

Diversion-p64: results from an international, prospective, multicenter, single-arm post-market study to assess the safety and effectiveness of the p64 flow modulation device.

BACKGROUND: The use of flow diversion to treat intracranial aneurysms has increased in recent years. OBJECTIVE: To assess the safety and angiographic efficacy of the p64 flow modulation device. METHODS: Diversion-p64 is an international, prospective, multicenter, single-arm, study conducted at 26 centers. The p64 flow modulation device was used to treat anterior circulation aneurysms between December 2015 and January 2019. The primary safety endpoint was the incidence of major stroke or neurologic death at 3-6 months, with the primary efficacy endpoint being complete aneurysm occlusion (Raymond-Roy Occlusion Classification 1) on follow-up angiography. RESULTS: A total of 420 patients met the eligibility criteria and underwent treatment with the p64 flow modulation device (mean age 55±12.0 years, 86.2% female). Mean aneurysm dome width was 6.99±5.28 mm and neck width 4.47±2.28 mm. Mean number of devices implanted per patient was 1.06±0.47, with adjunctive coiling performed in 14.0% of the cases. At the second angiographic follow-up (mean 375±73 days), available for 343 patients (81.7%), complete aneurysm occlusion was seen in 287 (83.7%) patients. Safety data were available for 413 patients (98.3%) at the first follow-up (mean 145±43 days) with a composite morbidity/mortality rate of 2.42% (n=10). CONCLUSIONS: Diversion-p64 is the largest prospective study using the p64 flow modulation device. The results of this study demonstrate that the device has a high efficacy and carries a low rate of mortality and permanent morbidity.

A traumatic pseudoaneurysm of the vertebral artery.

Although uncommon, vertebral artery pseudoaneurysms harbour significant risk of embolic stroke and their presence should be considered in cases of blunt cervical trauma. We illustrate a case of a traumatically ruptured vertebral artery pseudoaneurysm treated with coil embolisation.

Unlocking the 'locked-in syndrome'.

We present a case of a 48-year-old man who was initially thought to have had a brainstem stroke and was clinically 'locked-in'. Upon investigation, a petrous apex dural atriovenous fistula was identified causing profound brainstem venous hypertension. Surgical clipping lead to complete neurological recovery.

Early experience treating intracranial aneurysms using Accero: a novel, fully visible, low profile braided stent with platinum-nitinol composite wire technology.

BACKGROUND: Accero is an innovative, fully visible, self-expanding braided stent with platinum-nitinol composite wire technology, produced by Acandis. OBJECTIVE: To assess the technical success and safety of this new stent by evaluating the intraprocedural behavior and complication rate, and the short-term follow-up results. METHODS: Forty-one consecutive patients suitable for stent-assisted coiling were selected for the use of Accero in an 11-month period. Clinical, procedural, and angiographic data, as well as 30-day morbidity, were recorded. The angiographic results, clinical follow-up at 30 days, and early imaging follow-up at 3 or 6 months were analyzed, when available. RESULTS: Forty-one aneurysms were treated with stent-assisted coiling. All cases were elective, of which 19 were previously untreated aneurysms and 22 were recurrent aneurysms. Aneurysm location was anterior communicating artery complex (16), basilar (12 cases), middle cerebral artery bifurcation (9 cases), and internal cerebral artery (4 cases). The stent was successfully deployed and aneurysm occlusion with coils achieved in 100% of our patients. One case of on table in-stent thrombosis occurred, which resolved after administration of glycoprotein IIB/IIIA inhibitor, with no clinical consequence, and one case of postoperative hematoma at the arteriotomy site, which was managed conservatively. On early follow-up, available for 37 patients, the complete occlusion rate was 76%, with only two recurrences needing further treatment. Satisfactory aneurysm occlusion was therefore achieved in 95% of cases. CONCLUSION: Stent-assisted coiling with the Accero braided stent proved safe and effective.

Unusual case of intracranial dural AV fistula presenting with acute myelopathy.

We present a case of intracranial arteriovenous fistula with perimedullary venous drainage presenting with acute myelopathy, which is an unusual presentation of this uncommon condition. Subsequent catheter angiogram defined the arterial feeders from the meningohypophyseal trunk and petrosal branch of the middle meningeal artery. The patient was successfully embolised, resulting in complete obliteration of the fistula, and significant resolution of brainstem and cervical cord changes along with clinical improvement.

Qualitative assessment of brain anomalies in adolescents with mental retardation.

BACKGROUND AND PURPOSE: The neural basis of mental retardation is poorly understood. This study aimed to characterize structural anomalies of the brain in mental retardation and the relationship between them and the degree of mental retardation. METHODS: Eighty adolescents receiving educational support and 40 controls underwent MR brain imaging and intelligence quotient (IQ) assessment. MR images were evaluated according to a checklist of qualitative brain anomalies by a neuroradiologist blind to group membership. All scans were assessed by a second neuroradiologist to measure interobserver agreement. Ten percent of the studies were randomly selected for assessment of intraobserver agreement. RESULTS: Evaluation of MR images by using the checklist generated results with a high degree of interobserver and intraobserver agreement. Intraclass correlations were 0.93 and 0.75 for interobserver agreement on the total abnormality score and the entire checklist, respectively, and 0.97 and 0.85 for intraobserver agreement on the total abnormality score and the entire checklist, respectively. IQ is negatively correlated with the total abnormality score (P < .001). Subjects with an IQ <70 have a significantly greater total score (P = .003) and a significantly greater score for 12 specific anomalies, including thinning of the corpus callosum (P = .001) and abnormalities of the lateral ventricles. CONCLUSION: Mental retardation is associated with demonstrable brain anomalies, particularly thinning of the corpus callosum and ventricular abnormalities, and with a high total abnormality score. Greater levels of brain anomalies are associated with greater levels of mental retardation as evidenced by IQ.

Spontaneous subdural haematoma in a healthy young male.

The authors present an unusual case of a healthy young male who developed a spontaneous subdural haematoma. Headache was followed by blurring of vision and left upper limb symptoms. The diagnosis was made from a CT scan. Symptoms resolved with surgical decompression. The authors explore the risk factors and pathophysiology implicated in this condition. The authors demonstrate that apparently 'healthy' pursuits can have significant consequences, but the physician must also exclude serious underlying risk factors for bleeding, which the authors discuss.

Bacterial meningitis associated with a complex ischiorectal abscess.

We describe a case of bacterial meningitis in a 37 year old man resulting from the direct extension of an spontaneously occurring ischiorectal abscess into the intradural space. The patient presented with back pain and urinary retention and this was followed by the development of headache, photophobia and a left VIth nerve palsy. The patient was not diabetic or immunocompromised. He was treated with broad spectrum antibiotics and with drainage of the ischiorectal abscess; no organism was grown from blood, abscess contents or cerebrospinal fluid. He went on to make a full recovery.

Vascular plug for ICA occlusion in cavernous carotid aneurysms: technical note.

INTRODUCTION: Large, symptomatic aneurysms of the cavernous internal carotid artery (ICA) can be successfully treated by a combination of aneurysm coiling and occlusion of the parent vessel. CASE PRESENTATION: We describe the use of an Amplatzer (AGA medical corporation, Plymouth, MA, USA) detachable nitinol vascular plug to occlude the ICA in four patients with symptomatic cavernous ICA aneurysms.