Transorbital Approach Clipping of Middle Cerebral Artery Aneurysm: A Virtual Reality Morphometric Anatomic Study.

BACKGROUND: The transorbital approach (TOA) has a unique advantage to the more common lateral approaches as it provides direct access to the anterior middle fossa and medial sylvian fissure (SF) without significant dissection or retraction. However, when to use the TOA for surgical treatment of middle cerebral artery (MCA) aneurysms remains unclear. This study details the feasibility of clipping unruptured MCA aneurysms via the TOA by highlighting the anatomic features that either facilitate or hinder the approach. METHODS: Virtual reality (VR) models of 25 MCA aneurysms from computed tomography angiograms of actual patients were rendered with the relevant anatomic structures, including the neighboring temporal lobe and SF. TOA was performed on the models in VR and the globe was translated medially and inferiorly, replicating retraction used intraoperatively. Anatomic data, including the area of surgical freedom (AOF) at the aneurysm, were recorded. Trials of aneurysm clipping were conducted in VR and each aneurysm was classified as "possible" or "impossible" candidates for clipping via TOA. Separately, the relationship between surgical view and SF visualized was analyzed. RESULTS: Sixteen aneurysms were eliminated as candidates for TOA treatment either through VR clip trial and/or because the SF was inaccessible. The remaining 9 (36%) were candidates for TOA. Comparing the details of these 2 aneurysm categories with Mann Whitney U tests, there was a statistically significant difference in the AOF of the TOA approach and the width of the aneurysm dome. A clinical case report is also provided highlighting the VR rehearsal similarity with surgery. CONCLUSIONS: Given the minimally invasive, technically challenging approach, the feasibility and safety of TOA for MCA aneurysms must be evaluated before wide clinical adoption. This study identified AOF, aneurysm width, and SF accessibility as three features that may significantly impact the possibility of clipping MCA aneurysms via TOA.

An overview of decision-making in cerebrovascular treatment strategies: Part I - unruptured aneurysms.

Introduction: Unruptured intracranial aneurysm treatment has evolved over the last two centuries, starting from the introduction of aneurysm ligation and clipping, up until the inception of endovascular treatment and further advancements in both fields. Research question: The wide variety of aneurysm presentations and possible treatment modalities, complicates the understanding of decision-making for the treatment of a given aneurysm. The goal of this article is to provide an overview of the best available evidence concerning unruptured intracranial aneurysm decision-making and identify insights and hiatuses, as well as providing a scaffold to surpass the subjectiveness of decision-making. Materials and methods: A literature review was performed for the most impactful articles on decision-making in unruptured intracranial aneurysm treatment, to provide an overview on current practice. Results: Two groups of decision-altering factors were identified; patient-related and aneurysm-related factors. A summary is presented of the general evidence, and the influence of age, aneurysmal mass-effect, as well as size, morphological aspects and specific anatomical locations on decision-making. Discussion and conclusion: Decision-making for an unruptured intracranial aneurysm often comes down to combining these different patient- and aneurysm-related factors. In this paper, an evidence-based overview is provided into these different factors which alter management of unruptured saccular aneurysms.

Endoscopic clipping combined with cyanoacrylate injection vs. transjugular intrahepatic portosystemic shunt in the treatment of isolated gastric variceal bleeding: Randomized controlled trial.

OBJECTIVES: Although the incidence of isolated gastric varices type 1 (IGV1) bleeding is low, the condition is highly dangerous and associated with high mortality, making its treatment challenging. We aimed to compare the safety and efficacy of endoscopic clipping combined with cyanoacrylate injection (EC-CYA) vs. transjugular intrahepatic portosystemic shunt (TIPS) in treating IGV1. METHODS: In a single-center, randomized controlled trial, patients with IGV1 bleeding were randomly assigned to the EC-CYA group or TIPS group. The primary end-points were gastric variceal rebleeding rates and technical success. Secondary end-points included cumulative nonbleeding rates, mortality, and complications. RESULTS: A total of 156 patients between January 2019 and April 2023 were selected and randomly assigned to the EC-CYA group (n = 76) and TIPS group (n = 80). The technical success rate was 100% for both groups. The rebleeding rates were 14.5% in the EC-CYA group and 8.8% in the TIPS group, showing no significant difference (P = 0.263). Kaplan-Meier analysis revealed that the cumulative nonbleeding rates at 6, 12, 24, and 36 months for the two groups lacked statistical significance (P = 0.344). Similarly, cumulative survival rates at 12, 24, and 36 months for the two groups were not statistically significant (P = 0.916). The bleeding rates from other causes were 13.2% and 6.3% for the respective groups, showing no significant difference (P = 0.144). No instances of ectopic embolism were observed in either group. The incidence of hepatic encephalopathy (HE) in the TIPS group was statistically higher than that in the EC-CYA group (P = 0.001). CONCLUSION: Both groups are effective in controlling IGV1 bleeding. Notably, EC-CYA did not result in ectopic embolism, and the incidence of HE was lower than that observed with TIPS.

An overview of decision-making in cerebrovascular treatment strategies: Part II - Ruptured aneurysms.

Introduction: Decision-making for the treatment of ruptured aneurysms is an intricate process, which involves several factors. There has been a rapid advancement in endovascular, but also in the surgical treating field of ruptured intracranial aneurysms, with a growing body of evidence for either treatment technique. Research question: As there is a wide variety of treatment possibilities, it can be hard to understand the intricacies which lie behind the decision-making process for a given aneurysm. Materials and methods: An overview of the most relevant literature in decision-making on ruptured intracranial aneurysms is given. Results: Different decision-altering factors were identified, which can be divided into information from the general evidence, to influential factors such as the patient's age, initial presenting status, and aneurysmal factors such as size, morphology and aneurysmal location. Discussion and conclusion: This review provides an evidence-based overview of the most pertinent literature on these different aspects of decision-making in ruptured aneurysm cases and provides some recommendations after each of these segments. As always, all different aspects of the patient and aneurysmal factors should be taken into consideration before coming to a conclusion, as to obtain the best possible result for an individual patient.

Detection of Trypanosoma cruzi DNA in lizards: Using non-lethal sampling techniques in a sylvatic species with zoonotic reservoir potential in Chile.

Several reptile species have been described as hosts of Trypanosoma cruzi, the causative agent of Chagas disease, and therefore, they have become vertebrates of epidemiological interest. In recent decades, there has been a growing interest in animal welfare, especially in populations with small numbers where lethal sampling could have catastrophic consequences, and non-lethal methodologies have been developed for detecting zoonotic parasites. In this study, we compared three non-lethal sampling methodologies for detecting T. cruzi DNA in 21 captured specimens of the native lizard Liolaemus monticola, collected from the semiarid Mediterranean ecosystem of Chile. Specimens were subjected to xenodiagnosis (XD), tail clipping, and living syringe sampling procedures to evaluate whether lizards could serve as sentinel species for T. cruzi in endemic regions. To detect the protozoan, real-time PCR (qPCR) was performed on the DNA extracted from the samples (intestinal contents, tail tissues, and blood from living syringes). Trypanosoma cruzi DNA was detected in 12 of 21 lizards, considering all three methodologies. By XD, 12 specimens showed infection (57.1 %), and both living syringe and tail sampling methodologies detected only one infected lizard (4.8 %). Therefore, T. cruzi can be detected in lizards by qPCR using the three methodologies but XD is by far the most effective non-lethal detection methodology. The use of tail and living syringe methodologies showed a large underestimation; however, they might be options for monitoring the presence of T. cruzi in lizard populations when large sample sizes are available.

Characteristics of middle cerebral artery aneurysms treated endovascularly in a clip-favored institution.

BACKGROUND: The emergence of flow disruptors has brought a dynamic transition in the selection of treatment for middle cerebral artery (MCA) aneurysms, and the number of MCA aneurysms clipped is acceleratingly decreasing. Still, retreatment after endovascular treatment is still a dilemma, which may necessitate surgical clipping. It is all the more important to elucidate characteristics of MCA aneurysms that make clipping unfavorable. Thus, the practical characteristics of MCA aneurysms treated endovascularly in a clip-favored institution before the usage of flow disruption devices were investigated. METHODS: This is a retrospective, single-center observational study. The clinical and imaging characteristics of treated MCA aneurysms from January 2012 to May 2022 were analyzed. RESULTS: A total of 83 aneurysms were included; 70 aneurysms (84%) were clipped, and 13 (16%) were treated endovascularly. Eighteen aneurysms (22%) were ruptured (clipping, 12; endovascular, 6). The reasons for an endovascular treatment were as follows: distal (3); subacutely ruptured with burdens of spasm (2); multiple aneurysms (6: another clipped in 3, coiled in 1, and conservatively managed in 2); no access to the operating room due to COVID-19 (1); and retreatment after coiling (1). Endovascular group aneurysms were smaller (maximum diameter 5.2 vs 7.3 mm, p < 0.01, as well as dome, neck, and height) without differences in the dome/neck and aspect (height/neck) ratios. In a subgroup analysis of 78 MCA bifurcation aneurysms, the endovascular group was still smaller (dome 4.4 vs 5.8 mm, p = 0.025; neck 2.8 vs 3.9, p = 0.03). CONCLUSION: In a limited series from a clip-favored institution before the flow disruption era, factors guided to endovascular treatments on MCA aneurysms were rather anatomical and clinical factors such as distal location, subacutely ruptured, multiple, or retreatment after coiling, than morphological factors such as dome/neck and aspect ratios albeit smaller size.

Development and assessment of case-specific physical and augmented reality simulators for intracranial aneurysm clipping.

BACKGROUND: Microsurgical clipping is a delicate neurosurgical procedure used to treat complex Unruptured Intracranial Aneurysms (UIAs) whose outcome is dependent on surgeon's experience. Simulations are emerging as excellent complements to standard training, but their adoption is limited by the realism they provide. The aim of this study was to develop and validate a microsurgical clipping simulator platform. METHODS: Physical and holographic simulators of UIA clipping have been developed. The physical phantom consisted of a 3D printed hard skull and five (n = 5) rapidly interchangeable, perfused and fluorescence compatible 3D printed aneurysm silicone phantoms. The holographic clipping simulation included a real-time finite-element-model of the aneurysm sac, allowing interaction with a virtual clip and its occlusion. Validity, usability, usefulness and applications of the simulators have been assessed through clinical scores for aneurysm occlusion and a questionnaire study involving 14 neurosurgical residents (R) and specialists (S) for both the physical (p) and holographic (h) simulators by scores going from 1 (very poor) to 5 (excellent). RESULTS: The physical simulator allowed to replicate successfully and accurately the patient-specific anatomy. UIA phantoms were manufactured with an average dimensional deviation from design of 0.096 mm and a dome thickness of 0.41 ± 0.11 mm. The holographic simulation executed at 25-50 fps allowing to gain unique insights on the anatomy and testing of the application of several clips without manufacturing costs. Aneurysm closure in the physical model evaluated by fluorescence simulation and post-operative CT revealed Raymond 1 (full) occlusion respectively in 68.89% and 73.33% of the cases. For both the simulators content validity, construct validity, usability and usefulness have been observed, with the highest scores observed in clip selection usefulness Rp=4.78, Sp=5.00 and Rh=4.00, Sh=5.00 for the printed and holographic simulators. CONCLUSIONS: Both the physical and the holographic simulators were validated and resulted usable and useful in selecting valid clips and discarding unsuitable ones. Thus, they represent ideal platforms for realistic patient-specific simulation-based training of neurosurgical residents and hold the potential for further applications in preoperative planning.

From conservative to interventional management in unruptured intracranial aneurysms.

OBJECTIVE: Indication for treatment of unruptured intracranial aneurysms (UIAs) is based on several factors, such as patient age, previous medical history, and UIA location and size. For patients harboring UIAs initially managed noninvasively, the treatment strategy during follow-up (FU) can be changed to include surgical or endovascular intervention. This study aims to identify characteristic patterns and potential predictors of UIAs that require revision of the initial management strategy. METHODS: The authors identified intracranial aneurysm (IA) cases newly diagnosed between 2006 and 2022 and initially assigned conservative management. These cases were retrospectively reviewed for 1) patient and UIA characteristics at the time of diagnosis (patient age, comorbidities, previous medical history, potential risk factors, as well as UIA angioarchitecture, location, and size), and 2) any changes in treatment strategy (reason for change, time until intervention, modality of intervention). RESULTS: Among 1041 IA cases diagnosed in the study period, 144 were initially assigned conservative management. In 10 (6.9%) of these 144 cases, the treatment indication was modified to microsurgical clipping (n = 6) or endovascular embolization (n = 4) after a median FU of 26 months (IQR 8.5-64.5 months). In these 10 cases, the indication for intervention was attributable to IA growth (n = 7), a change in IA configuration (n = 2), or both (n = 1). Exploratory analyses of the effects of UIA size on diagnosis in terms of the hazard for a change of decision suggested an effect starting from 3 mm. No conservatively managed UIAs (n = 144) ruptured during the study period (median FU 24.5 months, IQR 7.75-55.75 months). CONCLUSIONS: The likelihood of a shift to invasive UIA treatment is relatively low if a conservative therapeutic strategy was initially established. However, for cases with changes to the treatment strategy, the change is most often attributable to UIA growth over time. UIAs measuring < 3 mm at initial diagnosis are less likely to be later treated interventionally than those > 3 mm at diagnosis. Therefore, conservatively managed patients with UIAs should be closely monitored with regular radiographic FUs, particularly if the UIA measured > 3 mm at the time of diagnosis.

Frequency dependence and harmonic distortion of stapes displacement and intracochlear pressure in response to very high level sounds.

Previous reports have suggested that intracochlear pressures (PIC) measured at the base of the cochlea increase directly proportionally with stapes displacement (DStap) in response to moderately high (<130 dB SPL) level sounds. Consistent with this assumption, we have reported that for low frequency sounds (<1 kHz), stapes displacement and intracochlear pressures increase linearly with sound pressure level (SPL) for moderately high levels (<130 dB SPL), but saturate at higher exposure levels (>130 dB SPL). However, the magnitudes of each response were found to be frequency dependent, thus the relationship between DStap and PIC may vary at higher frequencies or higher levels. In order to further examine this frequency and level dependence, measurements of DStap and PIC were made in cadaveric human temporal bones prepared with a mastoidectomy and extended facial recess to expose the ossicular chain. PIC was measured in scala vestibuli (PSV) and scala tympani (PST) simultaneously with SPL in the external auditory canal (PEAC) and laser Doppler vibrometry (LDV) measurements of stapes velocity (VStap). Consistent with prior reports, DStap and PSV increased proportionally with sound pressure level in the ear canal up to a frequency-dependent saturation point, above which both DStap and PSV showed a distinct deviation from proportionality with PEAC, suggesting that their relationship may remain constant at these high frequencies. Likewise, while the asymptotic value, and SPL at which saturation occurred were frequency dependent in both DStap and PSV, the reduction in gain with increasing SPL above this level was constant above this level at all frequencies, and the magnitude of responses at harmonics of the driving frequency increased with increasing level, consistent with harmonic distortion via peak clipping. Importantly, this nonlinear distortion shifts the energy arriving at the inner ear to higher frequencies than are present in incident stimulus, thus exposing the high frequency sensitive components of the auditory system to more noise than would be expected from measurement of that stimulus on its own. Overall, responses suggest that the cochlear representation of very high-level air conducted stimuli is limited by nonlinearities in the middle ear, and that this peak limiting leads to increased high frequency cochlear exposures than are present in the driving stimulus.

Preoperative Simulation of Intraoperative Findings in Surgical Clipping of Posterior Communicating Artery Aneurysms Using T2-Weighted 3D Images.

BACKGROUND: Tentorium resection and detachment from the oculomotor nerve are sometimes required for surgical clipping of unruptured posterior communicating artery (PCoA) aneurysms. Using T2-weighted 3D images, we aimed to identify the preoperative radiological features required to determine the necessity of these additional procedures. METHODS: We reviewed 30 patients with unruptured PCoA aneurysms who underwent surgical clipping and preoperative simulation using T2-weighted 3D images for measurement of the distance between the tentorium and aneurysm. Aneurysms were classified into superior type (superior to the tentorium) and inferior type (inferior to the tentorium). RESULTS: Seven patients (23%) underwent tentorium resection; all had the inferior type (superior vs. inferior, 0% vs. 33%, p = 0.071). In the 21 patients with the inferior type, the distance from the tentorium to the aneurysmal neck was 2.2 ± 1.1 mm and 0.0 ± 0.5 mm without and with tentorium resection (p < 0.01), respectively. An optimal cutoff value of ≤ +0.84 mm was identified for tentorium resection (area under the curve (AUC) = 0.96). Furthermore, 17 patients (57%) showed tight aneurysm attachment to the oculomotor nerve; all had the inferior type (0% vs. 81%, p < 0.01). The distance from the aneurysm tip to the tentorium was 1.1 ± 1.2 mm and -1.7 ± 1.4 mm without and with attachment (p < 0.01). The optimal cutoff value was ≤ +0.45 mm (AUC = 0.92). CONCLUSIONS: Measurement of the distance between the tentorium and aneurysmal neck or tip with T2-weighted 3D images is effective for preoperative simulation for surgical clipping of PCoA aneurysms.

Treatment factors to suppress delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage based on VASOGRADE: multicenter cohort study.

Delayed cerebral ischemia (DCI) is one of the most important outcome determinants for aneurysmal subarachnoid hemorrhage (aSAH). VASOGRADE, which combines World Federation of Neurological Surgeons grade and modified Fisher grade, is a useful scale for predicting DCI after aSAH. However, no studies have investigated whether VASOGRADE influences the treatment options. We retrospectively analyzed 781 aSAH patients who were prospectively enrolled in 9 primary stroke centers from 2013 to 2021. The total cohort consisted of 76 patients (9.7%) with VASOGRADE-Green, 390 patients (49.9%) with VASOGRADE-Yellow, and 315 patients (40.3%) with VASOGRADE-Red. Worse VASOGRADE had higher incidences of DCI, which occurred in 190 patients (24.3%). As only 5 patients (6.6%) with VASOGRADE-Green developed DCI, we searched for DCI-associated factors in patients with VASOGRADEs-Yellow and -Red. Multivariate analyses revealed independent treatment factors suppressing DCI as follows: no postoperative hemorrhagic complication, combined administration of fasudil hydrochloride and cilostazol, combination of clipping and cisternal drainage, and coiling for VASOGRADE-Yellow; and clipping, and administration of fasudil hydrochloride with or without cilostazol for VASOGRADE-Red. The findings suggest that treatment strategies should be determined based on VASOGRADE to prevent DCI after aSAH.

Contralateral approach to giant ruptured and unruptured ophthalmic artery aneurysms: patient series.

BACKGROUND: Giant ophthalmic artery (OphA) aneurysms remain surgically challenging despite the progress in endovascular treatments. This study describes the contralateral interoptic corridor in select patients based on imaging criteria suitable for clipping. The aim of this study was to show that despite the growing use of novel endovascular techniques, such as coil embolization and flow diversion, for the treatment of OphA aneurysms, microsurgical clipping may still be preferred for giant ones under certain conditions. OBSERVATIONS: The authors retrospectively reviewed the records of the microsurgical treatment of unruptured and ruptured giant OphA aneurysms at the University Hospital Center "Mother Teresa," Tirana, from 2007 to 2016. Four patients were selected for microsurgery and the contralateral approach using ophthalmic evaluations and coronal imaging on computed tomography, magnetic resonance imaging, and digital subtraction angiography that demonstrated aneurysms with a small neck and an orientation between 11 and 13 on the coronal clock face. A prefixed chiasm was a contraindication to this approach. LESSONS: Giant OphA aneurysms can be safely clipped through a contralateral interoptic corridor without creating new visual deficits or a residual aneurysm. https://thejns.org/doi/10.3171/CASE2473.

Classification of anatomy and treatment approaches for aneurysms originating from the proximal of the A1 segment of the anterior cerebral artery in clinical settings.

Objective: To explore the spatial relationship between A1 segment proximal anterior cerebral artery aneurysms and their main trunks, classify them anatomically and develop targeted treatment strategies. Methods: This single-center retrospective analysis involved 39 patients diagnosed with aneurysms originating from the proximal of A1 segment of the anterior cerebral artery (2014-2023). Classify the patient's aneurysm into 5 types based on the location of the neck involving the carrier artery and the spatial relationship and projection direction of the aneurysm body with the carrier artery, and outcomes from treatment methods were compared. Results: Among 39 aneurysms, 18 cases underwent endovascular intervention treatment, including 6 cases of stent assisted embolization, 1 case of flow-diverter embolization, 5 cases of balloon assisted embolization, and 6 cases of simple coiling. At discharged, the mRS score of all endovascularly treated patients was 0, and the GOS score was 5 at 6 months after discharge. At discharge, the mRS score of microsurgical clipping treated patients was 0 for 15 cases, 3 for 1 case, 4 for 1 case and 5 for 2 cases. Six months after discharge, the GOS score was 5 for 16 cases, 4 for 2 cases, 3 for 2 cases, and 1 for 1 case. GOS outcomes at 6 months were better for endovascularly treated patients (p = 0.047). Conclusion: Results showed better outcomes for the endovascular treatment group compared to microsurgical clipping at 6 months after surgery. The anatomical classification of aneurysms in this region may be of help to develop effective treatment strategies.

Microsurgical clipping of large MCA aneurysm in a 2-month-old child.

BACKGROUND: Cerebral aneurysms in children have a low incidence and accounts for less than 4% of all cerebral aneurysms. These aneurysms have been linked to various factors. Severe headache, seizures, and motor-sensory deficits are common presentations. CASE REPORT: We describe the case of a 2-month-old male patient who presented with generalized tonic-clonic seizures for 4 days. At the hospital, he was stabilized with ventilatory support, sedation, and antiepileptic drugs. A NCCT (Head) showed intraparenchymal hemorrhage in the left fronto-parieto-temporal lobe and subarachnoid hemorrhage. Subsequently a CT angiogram revealed an aneurysm of the left M3 segment of MCA. Successfully, the patient underwent microsurgical clipping of aneurysm and evacuation of hematoma. CONCLUSIONS: Pediatric cerebral aneurysms differ from their adult counterparts, mainly in their etiology and evolution. As per literature, aneurysmal clipping and neurological endovascular therapy have shown similar results.

Comparison of long-term clinical outcome after endovascular versus neurosurgical treatment of ruptured intracranial anterior circulation aneurysms: A single-centre experience.

Introduction: In patients with anterior circulation aneurysmal Subarachnoid Haemorrhage (aSAH), endovascular coiling is currently practiced more frequently than neurosurgical clipping. However, despite multiple previous studies, it is still uncertain whether coiling is favourable in terms of long-term clinical outcome. Research question: What is the effect of clipping versus coiling on long-term functional outcome of patients with an aSAH? Material and methods: All anterior circulation aSAH patients (2012-2015) treated with clipping or coiling in two hospitals in the Netherlands were studied up to five years after treatment. Functional outcome, survival, retreatment- and complication rate were measured. Survival analysis was performed in both groups. A multivariable regression model with covariate adjustment was performed to investigate the likelihood of unfavourable outcome (modified Rankin Scale >2). Results: Out of 204 patients, 75 patients were clipped (37%) and 129 received coiling (63%). Coiling had a higher retreatment rate compared to clipping (7.8% vs. 0.0%). Unfavourable outcome at six, 12, 24 and 60 months after treatment was higher for patients after clipping compared to coiling, but was not significant after correcting for clinical severity as represented by the WFNS grade. In 60 months, no difference in survival was found between clipping and coiling. Discussion and conclusion: No differences between clipping and coiling in survival and long-term functional outcome have been found in this study. More research with prospective design and large cohorts is needed to identify possible differences between the two treatments.

Efficacy of endovascular treatment for distal anterior cerebral artery aneurysms: A multicenter observational study.

OBJECTIVES: Distal anterior cerebral artery (DACA) aneurysms account for 1%-9% of all intracranial aneurysms. Microsurgical treatment is generally preferred for DACA aneurysms; however, it presents challenges owing to the anatomical complexities. Advances in neuro-interventional techniques have yielded promising results. This study aims to compare the clinical outcomes of DACA aneurysms treated with microsurgery and endovascular treatment (EVT) to elucidate the efficacy of EVT. MATERIALS AND METHODS: A multicenter observational registry comprising 16 stroke centers was utilized for this study. Data was retrospectively and prospectively analyzed from 166 patients with DACA aneurysms in our database, which included 4,552 consecutive patients with ruptured or unruptured intracranial aneurysms who underwent microsurgical or endovascular treatment between January 2013 and December 2021. RESULTS: Surgical clipping was performed in 115 patients, and 51 underwent coil embolization. The median follow-up duration was 15.3 months. No significant differences were observed in patient characteristics between the two treatment modalities. There were no differences in complication-related morbidity between the microsurgical treatment and EVT groups in either unruptured (10.5% vs. 9.1%, p=1.00) or ruptured aneurysms (5.2% vs. 6.9%, p=0.66). Coil embolization resulted in higher recurrence and retreatment rates than surgical clipping did, especially for ruptured aneurysms (2.6% vs. 27.6%, p<0.01). CONCLUSIONS: Endovascular treatment is an alternative to microsurgery for DACA aneurysms especially in unruptured cases or the patients who have difficulty undergoing craniotomy due to their general condition, albeit with considerations for higher recurrence and retreatment rates, particularly in ruptured cases. Close follow-up is crucial for the effective management of these challenges. Further studies are needed to refine the treatment strategies for DACA aneurysms.

Anterior choroidal artery aneurysms: a systematic review and meta-analysis of outcomes and ischemic complications following surgical and endovascular treatment.

OBJECTIVE: Anterior choroidal artery (AChA) aneurysms account for 2%-5% of all intracranial aneurysms. Treatment considerations include microsurgical clipping, flow diversion, or coiling with or without adjunctive devices. AChA aneurysms pose challenges in treatment due to the origination of the aneurysm from the origin or proximal segment of the AChA. The AChA is particularly susceptible to vasospasm and occlusion during treatment with devastating neurological deficits, including hemiparesis, hemianesthesia, lethargy, neglect, and hemianopia. In this study, the authors performed a meta-analysis to quantify the outcomes and complication rates across treatment modalities for AChA aneurysms and to identify risk factors reported in the literature. METHODS: The authors performed a systematic review of AChA aneurysms treated with surgical clipping, endovascular coiling, or flow diversion and reported in the PubMed, Embase, Scopus, and Cochrane search databases. Single-arm meta-analyses of the selected outcomes were performed in RStudio. RESULTS: Literature review yielded 25 studies that met the inclusion criteria. In total, 1627 patients were included in the analysis, with 554 males, 1009 females, and 64 unspecified. The rate of any complication in the full cohort was 11.6%, with a rate of ischemic complications of 5.5% and a favorable recovery rate of 90.3% of all patients treated. In total, 1064 patients underwent surgical clipping, 443 were treated with coiling, and 120 patients with flow diversion. In clipped patients, the rate of total surgical complications was 17.6%, with an ischemic complication rate of 9.4%. The rate of good functional recovery, defined on the basis of a Glasgow Outcome Scale score of 4-5 or modified Rankin Scale score of 0-2, was 88.0%, and complete obliteration was achieved in 84.5% of surgically clipped aneurysms. The complication rate in coiled patients was 10.3%, with an ischemic complication rate of 3.0%. Good functional recovery was achieved in 88.6% of coiled patients and complete aneurysm obliteration in 74.1%. Flow diversion resulted in a complication rate of 1.3%, with 0.7% rate of ischemic complications. Good functional recovery was achieved in 98.4% of patients and complete aneurysm obliteration in 79.0% in the flow diversion group. Aneurysm morphological features that impacted the complication rate were also identified to augment quantitative data and to help guide treatment selection for AChA aneurysms. CONCLUSIONS: Flow diversion showed significantly lower total and ischemic complications and improved outcomes compared to clipping and coiling. There may be differences in outcomes between treatment types, especially when considering the varied patient presentations that guide treatment selection.

Comparing surgical clipping with endovascular treatment for unruptured middle cerebral artery aneurysms: a systematic review and updated meta-analysis.

OBJECTIVE: Unruptured middle cerebral artery aneurysm (uMCAA) has traditionally been treated with open surgical clipping (SC). Endovascular treatments (EVTs) were designed to reduce surgical risks in these cases. Nevertheless, despite its potential benefits, many surgeons favor SC for uMCAA. This updated meta-analysis aimed to compare the safety, efficacy, and clinical outcomes of SC and EVT for uMCAA. METHODS: The authors searched the Medline, Embase, and Cochrane Library databases according to the Cochrane and PRISMA guidelines. Eligible studies included those with ≥ 4 patients with uMCAA reporting comparative data of SC and EVT. The endpoints were the complete occlusion rate (Raymond class I and II), good clinical outcomes (modified Rankin Scale score ≤ 2 or Glasgow Outcome Scale score ≥ 4), procedure-related complications (further divided into major and minor), and mortality. The authors pooled OR with 95% CI values with a random-effects model. I2 statistics were used to assess heterogeneity, and sensitivity analysis was conducted to address high heterogeneity. Publication bias was assessed with funnel plot analysis and the Egger's test. RESULTS: The analysis included data from 10 studies. Regarding the complete occlusion assessment, the comparative analysis revealed OR 0.17 (95% CI 0.08-0.40, p < 0.01), favoring SC. In terms of achieving good clinical outcomes, OR 0.44 (95% CI 0.20-0.97, p < 0.05) was determined, favoring SC. No differences regarding total procedure-related complications, major complications, or mortality were identified. However, a higher likelihood of minor complications was identified for EVT, with OR 4.68 (95% CI 2.01-10.92, p < 0.01). CONCLUSIONS: This systematic review and meta-analysis identified a lower likelihood of complete occlusion at last follow-up and lower likelihood of good clinical outcomes in patients treated with EVT when compared with SC. Furthermore, a higher likelihood of minor complications was identified in patients who underwent EVT when compared with SC. The findings reinforce that, based on the currently available data, SC should be considered the primary approach for treating uMCAA. However, EVT is an evolving approach, and this study's findings represent a synthesis of observational studies. Randomized trials are warranted to elucidate which approach should be the mainstay for uMCAA and to identify the nuances that determine whether SC or EVT is more or less indicated for addressing uMCAA with consideration of the individuality of each patient and aneurysm.

The safety and utility of the semi-sitting position for clipping of posterior circulation aneurysms.

BACKGROUND: The semi-sitting position offers advantages for surgeries in the posterior cranial fossa. However, data on its safety and effectiveness for clipping aneurysms in the posterior cerebral circulation are limited. This retrospective cohort study evaluates the safety and effectiveness of using the semi-sitting position for these surgeries. METHODS: We conducted a retrospective study of 17 patients with posterior cerebral circulation aneurysms who underwent surgical clipping in the semi-sitting position in the Department of Neurosurgery at Hannover Medical School over a 10-year period. RESULTS: The mean age at surgery was 62 years (range, 31 to 75). Fourteen patients were admitted with subarachnoid hemorrhage and 3 patients had incidental aneurysmas. Fifteen patients had PICA aneurysms, and two had aneurysms of the vertebral artery and the superior cerebellar artery, respectively. The median diameter of the aneurysms was 5 mm (range 3-17 mm). Intraoperative venous air embolism (VAE) occurred in 4 patients, without affecting the surgical or clinical course. VAE was associated with a mild decrease of EtCO2 levels in 3 patients and in 2 patients a decrease of blood pressure occurred which was managed effectively. Surgical procedures proceeded as planned in all instances. There were no complications secondary to VAE. Two patients died secondary to respiratory problems (not related to VAE), and one patient was lost to follow-up. Eleven of fourteen patients were partially or completely independent (Barthel index between 60 and 100) at a median follow-up duration of 13.5 months (range, 3-103 months). CONCLUSION: The semi-sitting position is a safe and effective technique for the surgical clipping of aneurysms in the posterior cerebral circulation. The incidence of VAE is comparable to that seen in tumor surgery. However, it is crucial for the surgical and anesthesiological team to be familiar with potential complications and to react immediately in case of an occurrence of VAE.

Surgical Management of Ipsilateral Internal Carotid Artery Stenosis and Unruptured Intracranial Aneurysm: Case Review and Treatment Considerations.

Introduction The coexistence of carotid artery stenosis and a concomitant downstream ipsilateral unruptured intracranial aneurysm requires unique treatment considerations to balance the risk of thromboembolic complications from carotid artery stenosis and the risk of subarachnoid hemorrhage from intracranial aneurysm rupture. These considerations include the selection of optimal treatment modalities, the order and timing of interventions, and potential management of antiplatelet agents with endovascular approaches. We present strategies to optimize treatment in such a case. Case Report We discuss the case of a 69-year-old woman with 90% stenosis of the right internal carotid artery and an ipsilateral, wide-necked, 4.8-mm, irregular-appearing right A1-2 junction aneurysm with an associated daughter sac. Open, endovascular, and mixed treatment strategies were considered. The patient selected and underwent a staged, open treatment approach with a carotid endarterectomy followed by a right craniotomy for microsurgical clipping of the aneurysm 5 days later. Both procedures were performed on daily full-dose aspirin without complications. On follow-up, the right carotid artery was widely patent, the aneurysm was secured, and the patient remained at her neurologic baseline. Discussion The presented strategy for ipsilateral carotid artery stenosis and an unruptured intracranial aneurysm initially optimized cerebral perfusion to mitigate ischemic risks while permitting timely aneurysm intervention without a need for dual antiplatelet therapy or to traverse an earlier procedure site.