Cigarette Smoking and Observed Growth of Unruptured Intracranial Aneurysms: A Systematic Literature Review and Meta-Analysis.

BACKGROUND: Smoking and observed growth of intracranial aneurysms are known risk factors for rupture. The mechanism by which smoking increases this risk is not completely elucidated. Furthermore, an association between smoking and aneurysm growth has not been clearly defined in the literature. We hypothesize that smoking is associated with aneurysm growth, which, in turn, may serve as one of the mechanisms by which smoking drives rupture risk. METHODS: We report a systematic review of the literature in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Using the R software, we performed a meta-analysis to investigate the association between smoking and the growth of unruptured intracranial aneurysms. Studies on familial aneurysms and genetic syndromes known to increase the risk of aneurysms were excluded. RESULTS: Eighteen observational studies were included with a total of 3535 patients and 4289 aneurysms with a mean follow-up period ranging from 17 to 226 months. The mean age among the studies ranged from 38.4 to 73.9 years; 74% of patients were female. Ever-smoking status (odds ratio, 1.10 [95% CI, 0.87-1.38]) and current smoking status (odds ratio, 1.43 [95% CI, 0.84-2.43]) did not show a statistically significant association with growth of intracranial aneurysms. Patients currently smoking did not have a statistically significant association with the growth of intracranial aneurysms (odds ratio, 1.18 [95% CI, 0.72-1.93]) compared with patients without a smoking history. No significant association was found in patients who previously smoked compared with patients who never smoked (odds ratio, 1.46 [95% CI, 0.88-2.43]). CONCLUSIONS: Smoking is not clearly associated with the growth of unruptured intracranial aneurysms, despite trends being observed, there is no statistical association. The mechanism by which smoking increases rupture risk might not be growth. In patients for whom observation is recommended, the absence of growth over time in the setting of smoking history does not, therefore, imply protection from rupture.

Natural History of Cavernous Carotid Artery Aneurysms: A Systematic Review and Meta-Analysis.

BACKGROUND: Cavernous carotid artery aneurysms (CCAAs) represent a common condition seen in clinical practice with significant practice variability. The aim of this systematic review and meta-analysis was to aggregate current evidence on the natural history of CCAAs. METHODS: MEDLINE/PubMed, EMBASE, and Cochrane Library were queried from inception until December 2023. The primary outcome of this study was CCAA-related mortality. The secondary outcomes of this study were aneurysm growth, intracranial ischemic and hemorrhagic events, improved non-cerebrovascular symptoms, and new or worsened non-cerebrovascular symptoms during follow-up. RESULTS: Ten studies met our inclusion criteria, involving 835 patients and 975 CCAAs. CCAA-related mortality had an incidence rate of 0.28 (95% CI 0.12-0.64) per 100 person-years (PYs) of follow-up. The incidence rate of CCAA growth was 2.91 (1.05-8.07) per 100 PYs of follow-up. The incidence rate of CCAA-related intracranial ischemic events was 0.4 (0.16-1.01) per 100 PYs of follow-up. The incidence rate of CCAA-related intracranial hemorrhagic events was 0.54 (0.33-0.87) per 100 PYs of follow-up. The incidence rate of improved non-cerebrovascular symptoms was 2.51 (1.18-5.33) per 100 PYs of follow-up. The incidence rate of new or worsened non-cerebrovascular symptoms was 3.41 (2.03-5.73) per 100 PYs of follow-up. CONCLUSIONS: CCAAs are typically benign lesions with a low risk of rupture and life-threatening complications. CCAAs tend to follow an indolent course regarding non-cerebrovascular outcomes, and new or worsening symptoms are infrequent during the clinical course. However, spontaneous resolution of non-cerebrovascular symptoms and cranial nerve deficits at presentation is uncommon.

Remote magnetic navigation enables precision telesurgery.

Medical devices actuated by external magnetic fields can create opportunities for clinical adoption of precision telesurgery.

Microsurgical Treatment of Pineal Tumors: Anatomy and Techniques.

Pineal region tumors are challenging lesions in terms of surgical accessibility and removal.1 The complexity is compounded by the infrequency and heterogeneity of pineal neoplasms.2,3 In Video 1, we present the case of a 39-year-old woman who presented with progressive headaches and vision impairment. She underwent microsurgical resection for a pineal parenchymal tumor of intermediate differentiation. We discuss the rationale, risks, and benefits of treatment for this patient, as well as provide a detailed overview of the alternative approaches that may be considered. Additionally, we discuss the unique anatomic considerations for each approach and include a virtual reality-compatible 3-dimensional fly-through to highlight the relationship between the tumor and relevant venous anatomy. The patient tolerated the procedure well with excellent neurologic outcome, and her follow-up imaging showed no evidence of tumor recurrence.

Predictive Model Evaluating Risk of Hemorrhage in Intracranial Aneurysms: Analysis from Prospectively Collected HEAT Trial Database.

OBJECTIVE: We analyzed the data of patients enrolled in the Hydrogel Endovascular Aneurysm Treatment (HEAT) trial to develop and validate a model to predict the risk of aneurysmal hemorrhage. METHODS: Analysis included data from 600 patients enrolled for the HEAT trial and included single saccular aneurysms of 3-14 mm size. Baseline characteristics were compared between patients with ruptured and unruptured aneurysms. Regression analysis was performed in the training set to identify significant risk factors and was validated in the validation dataset. The complete dataset was used to formulate a scoring model in which positive and negative predictors were assigned 1 and -1 points, respectively. RESULTS: Data from 593 patients were analyzed in which 169 (28.5%) patients had ruptured aneurysms. The training (n = 297) and validation dataset (n = 296) had a comparable proportion of ruptured aneurysms (29.3% and 27.7%). Dome-to-neck ratio >2.5 (odds ratio [OR] 3.66), irregular shape (OR 3.79), daughter sac (OR 5.89), and anterior and posterior communicating artery locations (OR 3.32 and 3.56, respectively) had a higher rupture rate. Use of aspirin was associated with lower risk of hemorrhage (OR 0.16). The area under the curve from the receiver operating curve analysis was 0.88, 0.87, and 0.87 in the training, validation, and combined data set, respectively. The scoring model created a score of -1 to 2, yielding an of aneurysmal hemorrhage probability from 1.5% (score -1) to 70% (score 2). CONCLUSIONS: This prospective study identifies dome-to-neck ratio >2.5, irregular shape, presence of daughter sac, absence of aspirin use, and aneurysm location at anterior communicating and posterior communicating artery as factors associated with increased risk of hemorrhagic presentation in small- to medium-sized intracranial aneurysms. Our model provides an estimate of rupture risk based on the presence or absence of these factors.

Cerebrospinal Venous Fistula Presenting with Cognitive Decline: Systematic Literature Review and Report of Two Cases.

OBJECTIVE: A cerebrospinal fluid (CSF) venous fistula (CVF) is an aberrant connection between the subarachnoid space and a vein resulting in CSF loss. The presentation and management of CVF with cognitive decline is incompletely understood. METHODS: A systematic review was completed following the PRISMA guidelines. Articles that included at least 1 case of imaging-confirmed CVF with details on patient treatment were included. A separate review of cases of patients with spontaneous intracranial hypotension (SIH) with frontotemporal dementia (FTD) or dementia symptoms was also completed. RESULTS: Ten CVF articles (69 patients; average age, 51.5 years) and 5 SIH with FTD or dementia articles (n = 41; average age, 55.9 years) were identified. Only 1 patients with CVF with cognitive abnormalities was identified. The most common symptom was headache in both reviews. Brain sag was identified in all patients, whereas CSF leak was identified in only 2 patients with SIH with FTD or dementia (4.9%). An epidural blood or fibrin glue patch was used in all patients with CVF and in 33 patients with SIH with FTD or dementia. Fifty-five patients with CVF (79.7%) and 27 patients with SIH with FTD or dementia (65.9%) had surgery. CONCLUSIONS: The 2 cases and literature reviews show the difficulty in diagnosis and treatment of CVF with cognitive decline. Novel imaging techniques should be used in patients with cognitive decline in whom a CSF leak is suspected. Transvenous embolization or surgery should be considered before patching for treatment of CVF-induced brain sag and resulting dementia.

Microsurgical Technique for Resection of a Cerebellopontine Angle Epidermoid Tumor.

Epidermoid tumors are slow-growing, benign, congenital lesions.1 They commonly arise in the cerebellopontine angle, fourth ventricle, suprasellar region, or spinal cord.2 Symptoms may include hearing loss, facial pain, and headaches. The management options include observation or surgical resection. If the patient has symptoms, surgical resection is the treatment option of choice with the goal of gross total resection. In Video 1, we discuss the microsurgical technique for the resection of a right cerebellopontine angle epidermoid tumor. A 22-year-old male patient presented with chronic headache, decreased right-sided hearing, right facial pain, and right facial twitching. Magnetic resonance imaging revealed the characteristic finding of an epidermoid tumor, which appeared as isointense on T1 and hyperintense on T2 with diffusion-weighted imaging. The patient was taken to the operating room, and a retrosigmoid craniotomy was performed on the basis of the transverse and sigmoid sinuses. The tumor capsule was opened, and the tumor was decompressed by removing the internal components consisting of epithelial keratin and cholesterol crystals, allowing for a gross total resection to be achieved. The patient's postoperative computed tomography scan showed no residual tumor, and the patient was discharged on postoperative day 1 in stable condition.

Clinical outcomes of first- and second-generation hydrogel coils compared with bare platinum coils: a systematic literature review.

Endovascular coiling has revolutionized intracranial aneurysm treatment; however, recurrence continues to represent a major limitation. The hydrogel coil was developed to increase packing density and improve neck healing and therefore decrease recurrence rates. In this paper, we review treatment outcomes of first- (1HCs) and second-generation (2HCs) hydrogel coils and compare them to those of bare platinum coils (BPC). A query of multiple databases was performed. Articles with at least 10 aneurysms treated with either 1HC or 2HC were selected for analysis. Collected data included aneurysm size, rupture status, initial occlusion, initial residual neck/aneurysm, packing density, mortality, morbidity, recurrence, and retreatment rates. The primary endpoint was recurrence at final follow-up. Secondary endpoints included residual neck and dome rates as well as procedure-related complications and functional dependence at final follow-up. Studies that compared 1HC to BPC showed significant lower recurrence (24% vs. 30.8%, p = 0.02) and higher packing density (58.5% vs. 24.1%, p < 0.001) in 1HC but no significant difference in initial occlusion rate (p = 0.08). Studies that compared 2HC to BPC showed lower recurrence (6.3% vs. 14.3%, p = 0.007) and retreatment rates (3.4% vs. 7.7%, p = 0.010) as well as higher packing density (36.4% vs. 29.2%, p = 0.002) in 2HC, with similar initial occlusion rate (p = 0.86). The rate of complications was not statistically different between HC (25.5%) and BPC (22.6%, p = 0.06). Based on our review, the 1HC and 2HC achieved higher packing density and lower recurrence rates compared to BPC. The safety profile was similar between both groups.

Real-Time MRI-Guided Stereotactic Aspiration of Spontaneous Intracerebral Hematoma: A Preclinical Feasibility Study.

BACKGROUND: Minimally invasive surgical techniques have reinvigorated the role of surgical options for spontaneous intracranial hematomas; however, they are limited by the lack of real-time feedback on the extent of hematoma evacuation. OBJECTIVE: To describe the development of a MRI-guided catheter-based aspiration system, the ClearPoint Pursuit Neuroaspiration Device (ClearPoint Neuro) and validation in phantom models. METHODS: In this preclinical experimental trial, 8 phantom brains with skull models were created to simulate an intracranial hematoma with 2 clot sizes, 30 cc (small clot) and 60 cc (large clot). After registration, the aspiration catheter (Pursuit device) was aligned to the desired planned trajectory. The aspiration of the clot was performed under real-time MRI scan in 3 orthogonal views. The primary end point was reduction of the clot volume to less than 15 cc or 70% of the original clot volume. RESULTS: Successful completion of clot evacuation was achieved in all models. The average postaspiration clot volume was 9.5 cc (8.7 cc for small clots and 10.2 cc for large clots). The average percentage reduction of clot volume was 76.3% (range 58.7%-85.2%). The average total procedure time (from frame registration to final postaspiration clot assessment) was 50 min. The average aspiration time was 6.9 min. CONCLUSION: This preclinical trial confirms the feasibility and efficacy of MRI-guided aspiration under real-time image guidance in simulation models for intracranial hematoma. Clinical use of the system in patients would further validate its efficacy and safety.

A comparison of treating physician versus independent core lab assessments of post-aneurysm treatment imaging outcomes: an analysis of prospectively collected data from a randomized trial.

OBJECTIVE: Aneurysm occlusion has been used as surrogate marker of aneurysm treatment efficacy. Aneurysm occlusion scales are used to evaluate the outcome of endovascular aneurysm treatment and to monitor recurrence. These scales, however, require subjective interpretation of imaging data, which can reduce the utility and reliability of these scales and the validity of clinical studies regarding aneurysm occlusion rates. Use of a core lab with independent blinded reviewers has been implemented to enhance the validity of occlusion rate assessments in clinical trials. The degree of agreement between core labs and treating physicians has not been well studied with prospectively collected data. METHODS: In this study, the authors analyzed data from the Hydrogel Endovascular Aneurysm Treatment (HEAT) trial to assess the interrater agreement between the treating physician and the blinded core lab. The HEAT trial included 600 patients across 46 sites with intracranial aneurysms treated with coiling. The treating site and the core lab independently reviewed immediate postoperative and follow-up imaging (3-12 and 18-24 months, respectively) using the Raymond-Roy occlusion classification (RROC) scale, Meyer scale, and recanalization survey. A post hoc analysis was performed to calculate interrater reliability using Cohen's kappa. Further analysis was performed to assess whether degree of agreement varied on the basis of various factors, including scale used, timing of imaging, size of the aneurysm, imaging modality, location of the aneurysm, dome-to-neck ratio, and rupture status. RESULTS: Minimal interrater agreement was noted between the core lab reviewers and the treating physicians for assessing aneurysm occlusion using the RROC grading scale (k = 0.39, 95% CI 0.38-0.40) and Meyer scale (k = 0.23, 95% CI 0.14-0.38). The degree of agreement between groups was slightly better but still weak for assessing recanalization (k = 0.45, 95% CI 0.38-0.52). Factors that significantly improved degree of agreement were scales with fewer variables, greater time to follow-up, imaging modality (digital subtraction angiography), and wide-neck aneurysms. CONCLUSIONS: Assessment of aneurysm treatment outcome with commonly used aneurysm occlusion scales suffers from risk of poor interrater agreement. This supports the use of independent core labs for validation of outcome data to minimize reporting bias. Use of outcome tools with fewer point categories is likely to provide better interrater reliability. Therefore, the outcome assessment tools are ideal for clinical outcome assessment provided that they are sensitive enough to detect a clinically significant change.

Microsurgical Clipping of a Postcoiling, Residual or Recurrent, Ruptured Anterior Communicating Artery Aneurysm.

Endovascular treatment modalities for intracranial aneurysms have seen a significant increase in popularity since the initial advent of the Guglielmi detachable coils in the early nineties.1 The publication of the International Subarachnoid Aneurysm Trial (ISAT) in addition to significant improvement in catheter and coil technology further cemented the endovascular-first approach, specifically for ruptured aneurysms.2 However, the increase in aneurysm coiling also led to a heightened awareness of its shortcomings, namely a significantly greater rate of recurrence and need for retreatment.3 The Cerebral Aneurysm Rerupture After Treatment (CARAT) study revealed that even though the rate of rerupture is low with both microsurgical and endovascular treatment modalities, the rate of rerupture is greater with incomplete versus complete aneurysm occlusion.4 Previously coiled aneurysms can be challenging to treat. While in some cases further endovascular therapies can be performed, microsurgical clipping remains a compelling alternative, specifically for small recurrent or residual ruptured aneurysms. However, microsurgical clipping of previously coiled aneurysms presents its own set of unique challenges. The presence of coils in the aneurysms increases the complexity of clip reconstruction. In addition, coil extrusion, which is often misdiagnosed as coil compaction on diagnostic imaging and therefore underreported, can further increase the risk of microsurgical dissection. In this operative video, we present a case of a postcoiling, residual or recurrent, ruptured anterior communicating artery aneurysm successfully treated through microsurgical clipping. The patient consented to the procedure as shown in this operative video (Video 1) and gave informed written consent for use of her images in publication.