Internal Carotid Artery Aneurysm Research Articles

Cardiac Arrest during Temporary Clipping for Ruptured Internal Carotid Artery Aneurysm: A Case Report

Abstract Objectives Mechanical stimulation of the trigeminal nerve during craniofacial, skull base, or dental surgeries may cause bradycardia, hypotension, or cardiac arrest. This phenomenon is called trigeminal cardiac reflex (TCR). We encountered a rare case of a patient who experienced sinus arrest due to temporary clipping of the intracranial carotid artery during the clipping of a ruptured aneurysm. We discuss possible reasons for the occurrence of TCR in this case. Materials and Methods A man in his 30s with no medical history presented with a sudden-onset headache. Computed tomography revealed a subarachnoid hemorrhage in the basal cistern and left Sylvian fissure. Angiography revealed a saccular aneurysm of the left internal carotid-anterior choroidal artery. A left frontotemporal craniotomy and dural incision were performed, followed by a trans-Sylvian approach. Cardiac arrest occurred twice during the temporary clipping of the intracranial carotid artery. After surgery, we performed a cardiac ultrasound echo and a 1-week Holter electrocardiogram. Neither showed abnormalities. No arrhythmia or cardiac events were observed over a one and half-year follow-up period. Results The cardiac arrest might have been triggered by the stimulation of the trigeminal nerve in the internal carotid artery. The repeated and anatomical features of this case suggest that TCR triggered cardiac arrest. Conclusion The high probability that cardiac arrest was induced by trigeminal nerve stimulation should be considered during the temporary clipping of the internal carotid artery. However, the predisposing factors and exact underlying mechanisms for these arrhythmias remain unknown and require further investigation.

Single Center Experience in Surgical Treatment of Extracranial Supra-Aortic Aneurysms

Objective To evaluate the effect of surgical treatment on extracranial supra-aortic aneurysms and summarize the experience. Methods The clinical data of 10 patients undergoing surgical treatment of extracranial supra-aortic aneurysms from May 2019 to November 2023 in the Department of Vascular Surgery of Beijing Tiantan Hospital affiliated to Capital Medical University were collected.The 10 patients included 5 patients with internal carotid artery aneurysm,2 patients with subclavian artery aneurysm,2 patients with vertebral artery aneurysm,and 1 patient with internal carotid artery aneurysm combined with ipsilateral subclavian artery aneurysm.The surgical indications,surgical regimens,clinical efficacy,and complications were retrospectively analyzed. Results All the 10 patients underwent surgery successfully,with the surgery duration range of 60-420 min and the median surgery duration of 180.0 (121.5,307.5) min.Intraoperative bleeding volume varied within 30-400 mL,with a median of 90 (50,125) mL.The time of carotid artery blocking and vertebral artery blocking varied within the ranges of 10-20 min and 20-30 min,with the medians of 15.0 (11.5,16.3) min and 25.0 (15.0,22.5) min,respectively.No cardiac accident,cerebral infarction,or cerebral hemorrhage occurred during the perioperative period.The 10 patients were followed up for 3-58 months,with the median follow-up time of 8.5 (5.3,17.0) months.One patient with subclavian artery aneurysm developed artificial vessel occlusion 20 months after surgery.One patient with internal carotid artery aneurysm developed distal carotid artery stenosis 6 months after surgery. Conclusion Surgical treatment should be actively adopted for extracranial supra-aortic aneurysms,and individualized surgical regimens should be designed according to patient conditions.

Role of aneurysmal hemodynamic changes in pathogenesis of headaches associated with unruptured cerebral aneurysms.

One symptom commonly associated with the presence of unruptured intracranial aneurysms is headache. In this study, the authors aimed to analyze factors associated with headaches among patients with intracranial aneurysms, with special consideration of hemodynamic parameters. The authors prospectively included 96 patients with 122 unruptured intracranial aneurysms. The authors obtained detailed medical history including current diseases and medications, as well as blood pressure values taken during hospitalization from the patients' medical records. The short-form McGill Pain Questionnaire was administered to each patient at admission and 3-6 months after the procedure to assess type and severity of headache. Based on imaging data, the authors obtained 3D reconstruction of each patients' aneurysm dome with feeding artery. The authors performed computational fluid dynamics analysis of blood flow through prepared models using OpenFOAM. Blood was modeled as Newtonian fluid, using the incompressible transient solver. Patient-specific internal carotid artery (ICA) blood velocity waves obtained with Doppler ultrasound were set as inlet boundary conditions. After performing simulation, the authors calculated the hemodynamic parameters of the aneurysm dome. A total of 30 patients (31.25%) reported having headaches. In multivariate logistic regression analysis, female sex (OR 2.81, 95% CI 2.51-4.86; p < 0.01), ICA aneurysm location (OR 7.93, 95% CI 5.51-8.52; p < 0.01), multiple aneurysms (OR 6.05, 95% CI 1.83-11.83; p = 0.02), mean dome blood velocity (OR 3.10, 95% CI 2.01-3.30; p < 0.01) and time-averaged wall shear stress (OR 1.18, 95% CI 1.47-2.72; p = 0.04) were independently associated with the presence of headache. Additionally, 17 patients (56.67%) reported complete relief of symptoms after the procedure. In multivariate logistic regression analysis, the mean blood flow in the ICA was independently associated with complete resolution of headaches after aneurysm treatment (OR 2.32, 95% CI 1.57-3.28; p < 0.01). Hemodynamic parameters of intracranial aneurysms might be associated with headaches and their relief after aneurysm treatment.

Management of a Twisted Flow Diverting Stent With a Balloon Mounted Cardiac Stent in a Pediatric Aneurysm: A Technical Report.

Giant aneurysms can present technical challenges during treatment with flow diversion including inability to access the aneurysm outflow directly. Encircling the aneurysm with a microwire/microcatheter has been well described; however, it can result in a twisted stent because of catheter twisting during the reduction maneuver, which, in turn, could lead to thromboembolic complications. Here, we describe a novel technique to manage the twist of the flow diverter in a giant internal carotid artery aneurysm using a combination of angioplasty and off-label placement of a balloon-mounted cardiac stent within the flow diverter. At 1 year, the aneurysm is completely occluded on digital subtraction angiography and MRI, and the patient is neurologically intact.

Comparative Efficacy of Flow Diverter Devices in the Treatment of Carotid Sidewall Intracranial Aneurysms: aRetrospective, Multicenter Study.

The comparative efficacy and safety of first-generation flow diverters (FDs), Pipeline Embolization Device (PED) (Medtronic, Irvine, California), Silk (Balt Extrusion, Montmorency, France), Flow Re-direction Endoluminal Device (FRED) (Microvention, Tustin, California), and Surpass Streamline (Stryker Neurovascular, Fremont, California), is not directly established and largely inferred. This study aimed to compare the efficacy of different FDs in treating sidewall ICA intracranial aneurysms. We conducted aretrospective review of prospectively maintained databases from eighteen academic institutions from 2009-2016, comprising 444 patients treated with one of four devices for sidewall ICA aneurysms. Data on demographics, aneurysm characteristics, treatment outcomes, and complications were analyzed. Angiographic and clinical outcomes were assessed using various imaging modalities and modified Rankin Scale (mRS). Propensity score weighting was employed to balance confounding variables. The data analysis used Kaplan-Meier curves, logistic regression, and Cox proportional-hazards regression. While there were no significant differences in retreatment rates, functional outcomes (mRS 0-1), and thromboembolic complications between the four devices, the probability of achieving adequate occlusion at the last follow-up was highest in Surpass device (HR: 4.59; CI: 2.75-7.66, p < 0.001), followed by FRED (HR: 2.23; CI: 1.44-3.46, p < 0.001), PED (HR: 1.72; CI: 1.10-2.70, p = 0.018), and Silk (HR: 1.0ref. standard). The only hemorrhagic complications were with Surpass (1%). All the first-generation devices achieved good clinical outcomes and retreatment rates in treating ICA sidewall aneurysms. Prospective studies are needed to explore the nuanced differences between these devices in the long term.

Catastrophic CPR-Related Injuries in Vascular Ehlers-Danlos Syndrome: A Case Report and Review.

This article presents a case of severe CPR-related injuries leading to diagnosis of vascular Ehlers-Danlos syndrome. The subject is a 36-year-old female with a past medical history of a 10-mm aneurysm of the right internal carotid artery discovered on imaging 3 years prior to death. Major autopsy findings included subarachnoid hemorrhage in the base of the brain, bilateral hemothoraces, hemopericardium, laceration of the interatrial septum, laceration of the left pulmonary artery, and changes secondary to chronic alveolar hemorrhage in the lungs. The autopsy findings and subsequent unremarkable toxicology studies led to the suspicion of an underlying and clinically undiagnosed connective tissue disorder. Broad genetic exome testing revealed a mutation consistent with vascular Ehlers-Danlos syndrome. An overview of this disease, its diagnosis, and differential are further described herein, along with recommendations for forensic pathologists.

Preliminary results of intracranial aneurysm treatment with derivo2heal embolization device

IntroductionThe Derivo 2 Heal Embolization Device (D2HED) is a novel flow diverter (FD) providing a fibrin-/heparin-based surface coating aiming at lower thrombogenicity. We evaluate periprocedural aspects and preliminary aneurysm occlusion efficacy for intracranial aneurysm treatment.MethodsThirty-four D2HEDs deployments (34 aneurysms, 32 patients) between 04/2021 and 10/2023 were analyzed. All patients were under dual antiplatelet therapy (dAPT). Periprocedural details, adverse events, and follow-up (FU) imaging were reviewed by consultant-level neuroradiologists. Complication rates and aneurysm occlusion efficacy are compared with performance data of other FDs based on literature research.ResultsEach intervention succeeded in the deployment of one D2HED. Significant and/or increased intraaneurysmal contrast stagnation immediately after D2HED deployment was seen in 73.5% of cases according to O’Kelly-Marotta (OKM) grading scale. Clinically relevant early adverse events occurred in three patients: Among them two cases with fusiform aneurysms in the posterior circulation (ischemic events, early in-stent-thrombosis) and one patient (ischemic event) out of the majority of 31 treated internal carotid artery aneurysms (3,2%). Regarding mid-term FU (> 165 days), one aneurysm did not show progressive occlusion presumably caused by a prominent A1 segment arising from the terminal ICA aneurysm itself. Apart from that, mid-term complete / partial occlusion rates of 80% / 20% could be demonstrated.ConclusionOur case series - although suffering from restricted sample size - suggests a potential effectiveness of D2HED in managing intracranial aneurysms. Further studies with larger samples are warranted to quantify long-term occlusion efficacy and the impact of antithrombogenic surface coating on the necessary (d)APT.

Benign Natural Progression of Small Cavernous Carotid Aneurysms Suggests Limited Clinical Utility of Serial Longitudinal Follow-up.

Aneurysms in the cavernous segment of the internal carotid artery (ICA) often present in an indolent fashion with limited morbidity. However, their growth progression and possible rupture over time remains poorly defined, thereby limiting optimization of serial follow-up. Thus, we aim to describe the progression of cavernous ICA aneurysms over time, as well as the patient and aneurysm characteristics associated with possible growth and rupture status. We identified a consecutive cohort of 157 patients from 2007 to 2021 with cavernous ICA aneurysms. Patient demographic data, possible risk factors, presenting symptoms, radiographic features of aneurysms, size progression, rupture status, and concomitant noncavernous aneurysm rupture data were manually extracted. One hundred and fifty-seven patients (mean age at diagnosis 57.2 ± 15.6 years; 85.4% females) with 174 cavernous carotid aneurysms (CCAs) were followed for an average of 7.1 ± 4.8 years. 76.4% of aneurysms were identified incidentally, with predominantly ocular palsies as the presenting symptoms in remaining primary cases. Most aneurysms were small, and of the 168 aneurysms that were followed, 98.2% did not demonstrate appreciable growth. Of the aneurysms that grew, it took an average of 6.0 years to grow 1.6 ± 0.2 mm. Demographic data, hypertension, and smoking status were not associated with aneurysm growth. Most radiographic features also were not associated with growth, except long-axis diameter, which had an odds ratio of 1.4 (CI: 1.2, 1.8) on multivariable analysis. Presenting clinical symptoms were not associated with growth. No CCAs ruptured during follow-up. Cavernous ICA aneurysms in our series demonstrate no rupture and limited growth over years of clinical follow-up. No radiographic or patient risk factors were associated with growth except initial aneurysm size. Hence, small CCAs may not require close follow-up over time.

Treatment of an intracranial aneurysm in the setting of fenestration of cranial division of the internal carotid artery: Technical considerations and a literature review.

Although rare, cerebral arterial fenestration may present challenges in diagnosis and treatment. Here we present a case of a supraclinoid internal carotid artery (ICA) fenestration adjacent to an ICA aneurysm, successfully treated with balloon-assisted coil embolization. A female in her 50's presented with an acute subarachnoid hemorrhage from a ruptured left ICA-ophthalmic artery (OA) aneurysm. Digital subtraction angiography revealed a focal ICA fenestration distal to the posterior communicating artery (Pcom). The patient underwent successful coil embolization of the aneurysm using the balloon-assisted technique. No immediate hemorrhagic, thromboembolic, or neurological complications were observed. The patient was discharged in good condition after 2 weeks of hospitalization. A comprehensive literature review of 33 cases was subsequently performed to understand the characteristics of this condition. Cases involving the cranial division of the ICA forming the fenestration exhibited caliber differences significantly more frequently (p = 0.02). Embryological insights revealed distinctions between the cranial divisions of the ICA, influencing fenestration morphology and associated aneurysm formation. Endovascular treatment poses the risk of vascular injury, necessitating the identification of this variation and procedural planning.

Pre-rupture syndrome

Oculomotor nerve palsy can be a strong indicator of an internal carotid artery aneurysm, specifically of the posterior communicating artery, due to the anatomical positioning within the basal cisterns of the subarachnoid space, which allows for nerve compression. This condition can predict an acute subarachnoid haemorrhage, associated with a high mortality rate, often presenting with sudden, severe headaches, with or without deficits. The pathophysiology theories include direct mechanical compression by the aneurysmal sac, arterial pulsations, and nerve tissue oedema from venous obstruction. In cases of unruptured aneurysms, nerve irritation is less common. This palsy occurs in about one-third of cases. Aneurysmal orientation can vary (lateral, superior, inferior, medial, posterior), and due to the nerve’s anatomical position, aneurysms in the postero-lateral-inferior position are more likely to cause nerve damage. Treatment opinions vary from observation to intervention, with options including traditional neurosurgery and endovascular embolization. The latter is increasingly preferred due to its efficacy and lower risk profile. A clinical case involves a 56-year-old female presenting with ptosis, diplopia, and ipsilateral mydriasis. Imaging confirmed a posterior communicating artery aneurysm with a maximum diameter of 5.3 mm and a 3 mm bleb. Endovascular coiling was performed successfully, excluding the aneurysm from circulation without complications. Post-treatment, the patient was discharged in good condition with recommendations for periodic monitoring. In conclusion, while no single best treatment exists for posterior communicating artery aneurysms with oculomotor nerve palsy, early intervention (surgical or endovascular) and patient monitoring are crucial for preventing complications and ensuring quality of life.

Flow Diverter

The flow diverter is a relatively new but revolutionary technology in the realm of Endo vascular management of complex cerebral aneurysms. The traditional approach in the past has been stent deployment assisted coil embolisation. However, this maybe associated with partial occlusion or late recanalisation of the aneurysm. While planning the procedure for any cerebral aneurysm, the neurosurgeon needs to consider the morphology of the intracranial aneurysm as well as its proximity to the vascular branches and perforators. Giant (&gt;25mm diameter), large (&gt;10mm diameter), wide necked and fusiform aneurysms are the most challenging ones to treat.(1) The flow diverter works on the following principles (a)the stent deployed disrupts the blood flow from the parent vessel into the aneurysm (b) the stent works like a scaffolding for the growth of endothelial cells and separates the aneurysm from the parent vessel and gradually blocks it.(2) It is inducing endoluminal reconstruction in contrast to endosaccular filling in the older procedures. Moreover, it spares the origin of perforators from getting occluded. The sac gradually shrinks and finally collapses. This has excellent outcomes in comparison to conventional procedures for large or wide-necked aneurysms. This fascinating, innovative technology is associated with lesser complications and higher success rates. It is backed by landmark trials including the ‘Pipeline Embolisation Device for the Intracranial treatment of Aneurysms (PITA)’ trial and the ‘Pipeline for Uncoilable or Failed Aneurysms (PUFs) trial.(1) The device has thrombogenic potential and the patient needs to be on anti platelet therapy to prevent thromboembolism and late in-stent stenosis. A diversified complex case of multiple giant internal carotid artery aneurysms managed by latest phenomenal advanced technique of flow diversion in Neurointervention spectrum, that is, FLOW DIVERTER (FD). This young lady presented with sudden onset right sided complete opthalmoplegia and headache. Her investigations revealed bilateral ICA large to giant aneurysms. Considering all aspects of her case, she was counselled and planned for FD placement with some coils.

Clinical and Hemodynamic Features of Aneurysm Rupture in Coil Embolization of Intracranial Aneurysms.

Intraprocedural rupture (IPR) during coil embolization (CE) of an intracranial aneurysm is a significant clinical concern that necessitates a comprehensive understanding of its clinical and hemodynamic predictors. Between January 2012 and December 2023, 435 saccular cerebral aneurysms were treated with CE at our institution. The inclusion criterion was extravasation or coil protrusion during CE. Postoperative data were used to confirm rupture points, and computational fluid dynamics (CFD) analysis was performed to assess hemodynamic characteristics, focusing on maximum pressure (Pmax) and wall shear stress (WSS). IPR occurred in six aneurysms (1.3%; three ruptured and three unruptured), with a dome size of 4.7 ± 1.8 mm and a D/N ratio of 1.5 ± 0.5. There were four aneurysms in the internal carotid artery (ICA), one in the anterior cerebral artery, and one in the middle cerebral artery. ICA aneurysms were treated using adjunctive techniques (three balloon-assisted, one stent-assisted). Two aneurysms (M1M2 and A1) were treated simply, yet had relatively small and misaligned domes. CFD analysis identified the rupture point as a flow impingement zone with Pmax in five aneurysms (83.3%). Time-averaged WSS was locally reduced around this area (1.3 ± 0.7 [Pa]), significantly lower than the aneurysmal dome (p < 0.01). Hemodynamically unstable areas have fragile, thin walls with rupture risk. A microcatheter was inserted along the inflow zone, directed towards the caution area. These findings underscore the importance of identifying hemodynamically unstable areas during CE. Adjunctive techniques should be applied with caution, especially in small aneurysms with axial misalignment, to minimize the rupture risk.

Intracranial Aneurysms Managed by Parent Artery Reconstruction Using Tubridge Flow Diverter study: 1-year outcomes.

Previous randomized controlled trials have reported a significantly higher occlusion rate of large and giant aneurysms when utilizing the Tubridge flow diverter (FD). In the present trial, the safety and efficacy of the Tubridge FD in treating unruptured internal carotid artery (ICA) or vertebral artery (VA) aneurysms were assessed in a real-world setting. The Intracranial Aneurysms Managed by Parent Artery Reconstruction Using Tubridge Flow Diverter (IMPACT) study is a prospective, multicenter, single-arm clinical trial assessing the efficacy of the Tubridge FD in the management of unruptured aneurysms located in the ICA or VA. The primary endpoint was the complete occlusion (Raymond-Roy class 1) rate at the 1-year follow-up. The secondary endpoints included the technical success rate, the successful occlusion rate of the aneurysm, which is the degree of aneurysm embolization scored as Raymond-Roy class 1 or 2, major (> 50%) in-stent stenosis, and incidence of disabling stroke or neurological death associated with the target aneurysms. This study included 14 interventional neuroradiology centers, with 200 patients and 240 aneurysms. According to angiographic core laboratory assessment, 205 (85.4%) aneurysms were located in the ICA, 34 (14.2%) in the VA, and 1 (0.4%) in the middle cerebral artery. Additionally, 189 (78.8%) aneurysms were small (< 10 mm). At the 12-month follow-up, the total occlusion rate was 79.0% (166/210, 95% CI 72.91%-84.34%). Additionally, the occurrence of disabling stroke or neurological death related to the specified aneurysms was 1% (2/200). The 1-year results from the IMPACT trial affirm the safety record of use of the Tubridge FD in the treatment of intracranial aneurysms in real-world scenarios. These results reveal low morbidity and mortality rates of 3.5% and 1.5%, respectively. Furthermore, they provide evidence of the effectiveness of the Tubridge FD, as demonstrated by the complete occlusion achieved in 166 of 210 (79%) cases.

Catastrophic rupture of an internal carotid aneurysm in a neurofibromatosis type 1 patient: A critical case study

Catastrophic rupture of an internal carotid aneurysm in a neurofibromatosis type 1 patient: A critical case study

Patient-specific cerebral 3D vessel model reconstruction using deep learning

Three-dimensional vessel model reconstruction from patient-specific magnetic resonance angiography (MRA) images often requires some manual maneuvers. This study aimed to establish the deep learning (DL)-based method for vessel model reconstruction. Time of flight MRA of 40 patients with internal carotid artery aneurysms was prepared, and three-dimensional vessel models were constructed using the threshold and region-growing method. Using those datasets, supervised deep learning using 2D U-net was performed to reconstruct 3D vessel models. The accuracy of the DL-based vessel segmentations was assessed using 20 MRA images outside the training dataset. The dice coefficient was used as the indicator of the model accuracy, and the blood flow simulation was performed using the DL-based vessel model. The created DL model could successfully reconstruct a three-dimensional model in all 60 cases. The dice coefficient in the test dataset was 0.859. Of note, the DL-generated model proved its efficacy even for large aneurysms (> 10 mm in their diameter). The reconstructed model was feasible in performing blood flow simulation to assist clinical decision-making. Our DL-based method could successfully reconstruct a three-dimensional vessel model with moderate accuracy. Future studies are warranted to exhibit that DL-based technology can promote medical image processing.Graphical

Fungal carotiditis with aneurysm - a rare complication of mucormycosis: presentation and management

During the COVID-19 pandemic, cases of mucormycosis (ROCM) had increased drastically, especially in the second wave. Most of these cases involved the paranasal sinuses, orbit and occasionally brain. This case report presents a rare case of mucormycosis complicated with a mycotic aneurysm of the petrous part of the internal carotid artery (ICA). A 43-year-old man presented with left-sided facial weakness for which high resolution computed tomography scan of the Temporal bones was done. A scrutiny of the computed tomography temporal bone showed evidence of osteomyelitis extending to the petrous apex around the foramen Lacerum. Computed tomography and magnetic resonance imaging of the paranasal sinus done later confirmed the diagnosis of mucormycosis. The patient underwent endoscopic surgical debridement of the nose and sinuses, with post-operative amphotericin B. After 3 weeks, the patient presented with bouts of profuse nasal bleed. Computed tomography angiogram showed an aneurysm in the petrous segment of the ICA suggestive of mycotic carotiditis complicated from mucormycosis spread along the skull base. It was successfully managed neurosurgically by a bypass shunting procedure. Mucormycosis is a disease that typically has an aggressive and startling fatality rate. ICA aneurysm is an uncommon occurrence in mucormycosis. Subjects with ROCM should be examined for brain and vascular involvement. Computed tomography angiogram should be performed as soon as possible if the skull base is involved in the ICA area. Morbidity and mortality can often be reduced by early diagnosis and interventions by a multidisciplinary team.

The critical role of neuroimaging in hemicrania continua: Asystematic review and case series.

Hemicrania continua is a primary unilateral headache characterized by ipsilateral parasympathetic and sympathetic autonomic features. A key diagnostic criterion is its dramatic response to indomethacin treatment; however, various vascular or structural abnormalities have been reported to cause secondary hemicrania continua, presenting with clinical features similar to those of the primary headache presentation. We reviewed the literature to compile secondary hemicrania continua cases, highlighting the importance of imaging during the evaluation. Additionally, we also contributed our three cases to the existing studies. We conducted a review of articles from the PubMed and EMBASE databases that described reported cases of secondary hemicrania continua, covering the period from 1993 to 2021. Our review included detailed patient information, signs, and symptoms of hemicrania continua, as well as information on indomethacin usage and headache resolution (if pertinent). Secondary hemicrania continua can result from a remarkably diverse range of structural and vascular lesions, yet clinical reports on long-term follow-up are lacking. Notably, cases may exhibit a classical response to indomethacin, emphasizing the importance of neuroimaging in excluding secondary cases. Our search yielded 41 cases meeting our criteria. We excluded six cases that were not treated with indomethacin or were unresponsive to it. Additionally, we present three cases that highlight the necessity of neuroimaging in evaluating hemicrania continua, along with short- and long-term clinical outcomes following indomethacin and lesion-directed treatments. Case 1 presented with daily right-sided headaches and cranial autonomic symptoms. Her pain completely resolved with indomethacin use. Neuroimaging of the brain revealed a laterally directed saccular aneurysm of the right internal carotid artery. Case 2 presented with continuous left-sided unilateral headaches with superimposed exacerbations. She complained of left-sided photophobia with a dull sensation in the left ear. Her symptoms decreased after 2 weeks of indomethacin use. Neuroimaging of the head indicated a benign tumor with mass effect into the left lateral medulla and inferior cerebellar peduncle. Case 3 presented with a right side-locked headache with daily, severe superimposed exacerbations. She had photophobia in the right eye and a right-sided Horner's syndrome, along with tearing during her exacerbations. Neuroimaging of the brain revealed a pituitary tumor and her pain completely resolved with indomethacin. Hemicrania continua is a rare headache disorder that can be either primary or secondary. Importantly, response to indomethacin can still occur in secondary hemicrania continua. Thus, neuroimaging should be considered to rule out underlying structural etiology in all cases, regardless of their clinical responsiveness to indomethacin therapy.

Flow Diversion Effect in a Saphenous Vein Graft Aneurysm Using a Double-Layer Micromesh Stent: A Case Report.

A double-layer micromesh stent is designed for the treatment of carotid artery stenosis that has been reported to potentially provide a flow diversion effect. However, the actual flow diversion effect of stents remains unclear. Here, we present a case of a growing saphenous vein graft (SVG) aneurysm treated with the placement of the double-layer micromesh stent using its flow diversion effect. A 66-year-old woman, who underwent high-flow bypass using a SVG for a blister-like internal carotid artery aneurysm 13 years earlier at our institute, was referred to our hospital with a pulsatile cervical mass. Magnetic resonance angiography showed a 9-mm aneurysm on the left SVG, although the aneurysm was a small pouch 4 years earlier. Digital subtracted angiography demonstrated a 9.4 × 8.3-mm aneurysm from the SVG at the auricular level. Because the diameter of the graft was larger than that of the available flow diverter stents in Japan, we decided to place the double-layer micromesh stent (CASPER RX, 7 × 25 mm MicroVention) using its flow diversion effect. Computational fluid dynamics analysis before and after stent deployment showed a significant reduction in the average flow velocity and wall shear stress in the aneurysm, indicating actual flow diversion. An angiogram 2 months postoperatively showed complete obliteration of the aneurysm. Obliteration of the saphenous vein aneurysm was achieved because of the flow diversion effect of the double-layer micromesh stent. The stents might be a feasible alternative for treating cervical carotid aneurysms.

Thromboembolic Events After the Coverage of Anterior Cerebral Artery with Flow Diversion: A Single Institution Series and Systematic Review

Advances in the use of flow diversion (FD) now extend to bifurcation aneurysms; herein, we compare thromboembolic events in patients with internal carotid artery (ICA) aneurysms treated with and without exclusion of the anterior cerebral artery (ACA). Retrospective analysis of aneurysms in the terminal ICA treated with FD from 2013 to 2023 at a single-center study. Procedures were classified according to the coverage at the origin of the ACA and compared through bivariate-analysis. A review was also carried on PubMed, Web of Science, and EMBASE until April 2024, adhering to the PRISMA reporting guidelines. Ninety-five patients harboring 113 aneurysms treated in 102 procedures were evaluated. Fifty-eight were treated covering the ACA origin. Dual antiplatelet regimens included aspirin-clopidogrel (50%), aspirin-ticagrelor (44.1%), and aspirin-prasugrel (4.9%). Thromboembolic events occurred in 6 patients (5.9%), all of which presented with large vessel occlusion of the ICA, but without reaching statistical difference in the 2 treated cohorts (P= 0.46). At a median clinical follow-up of 5.95months, there were no differences in the functional outcomes in the 2 groups (P= 0.22). Contralateral angiographic runs post-treatment after covering the ACA origin demonstrated increase in the A1 (median: 0.45mm; IQR=0.4-1.2) and ICA diameter (median: 0.55mm; IQR=0.1-1.2). After pooling data from literature and our cohort, complete side branch occlusion after the coverage of ACA was seen in 25% of branches (95%CI=0.16-0.36), and thromboembolic events were observed after 3% (95%CI=0.01-0.04) of procedures. Thromboembolic events can occur in distal ICA aneurysms treated with FD, but no significant association was seen with covering the ACA origin.

Contralateral Prechiasmatic Interoptic Approach for Microsurgical Clip Ligation of a Medially Pointing Paraclinoid Internal Carotid Artery Aneurysm

Contralateral Prechiasmatic Interoptic Approach for Microsurgical Clip Ligation of a Medially Pointing Paraclinoid Internal Carotid Artery Aneurysm