Endoscopic Eyebrow Approach for Aneurysms.

INTRODUCTION: Considerable effort has been made to reduce surgical invasiveness, since Axel Perneczky introduced the supraorbital eyebrow approach as a core part of his keyhole concept in neurosurgery. But a limited approach does not facilitate an already serious and demanding task as aneurysm surgery. In this regard, the enhancement of the visual field before, during, and after microsurgical aneurysm occlusion is a safe and effective method to increase the quality of treatment. Indications/Contraindications: Based on the individual anatomical findings, the supraorbital keyhole approach provides access to most aneurysms of the anterior circulation. The approach is not recommended in large complex aneurysms, giant aneurysms, BA aneurysms located beneath the dorsum sellae, as well as cases of severe subarachnoid hemorrhage (SAH) and expected brain edema. COMPLICATIONS: Experience with endoscopic procedures in aneurysm surgery is limited to several clinical retrospective articles, and no major complications in conjunction with the endoscope were observed. Outcome and Prognosis: The supraorbital eyebrow approach has a low rate of complications and provides highly favorable cosmetic results. Endoscopic inspection prior to clipping might reduce overexposure and mobilization of the aneurysm. It was found that the rate of intraoperative rupture was decreased. The endoscopic post-clipping control helped significantly to reduce aneurysm remnants and unattended parent, branch, or perforator occlusion. CONCLUSION: The supraorbital eyebrow approach is a safe, effective and elegant approach in the treatment of most aneurysms of the anterior circulation. The additional enhancement of the visual field provided by the endoscope before, during, and after microsurgical aneurysm clipping might decrease the rate of intraoperative aneurysm ruptures and unexpected findings concerning aneurysm remnant occlusion and compromise of involved parent, branching, and perforating vessels.

Efficacy and safety of adenosine, rapid ventricular pacing and hypothermia in cerebral aneurysms clipping: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Cerebral aneurysms in complex anatomical locations and intraoperative rupture can be challenging. Many methods to reduce blood flow can facilitate its exclusion from the circulation. This study evaluated the safety and efficacy of using adenosine, rapid ventricular pacing, and hypothermia in cerebral aneurysm clipping. METHODS: Databases (PubMed, Embase, and Web of Science) were systematically searched for studies documenting the use of adenosine, rapid ventricular pacing, and hypothermia in cerebral aneurysm clipping and were included in this single-arm meta-analysis. The primary outcome was 30-day mortality. Secondary outcomes included neurological outcomes by mRs and GOS, and cardiac outcomes. We evaluated the risk of bias using ROBIN-I, a tool developed by the Cochrane Collaboration. OpenMetaAnalyst version 2.0 was used for statistical analysis and I2 measured data heterogeneity. Heterogeneity was defined as an I2 > 50%. RESULTS: Our systematic search yielded 10,100 results. After the removal of duplicates and exclusion by title and abstract, 64 studies were considered for full review, of which 29 were included. The overall risk of bias was moderate. The pooled proportions of the adenosine analysis for the different outcomes were: For the primary outcome: 11,9%; for perioperative arrhythmia: 0,19%; for postoperative arrhythmia: 0,56%; for myocardial infarction incidence: 0,01%; for follow-up good recovery (mRs 0-2): 88%; and for neurological deficit:14.1%. In the rapid ventricular pacing analysis, incidences were as follows: peri operative arrhythmia: 0,64%; postoperative arrhythmia: 0,3%; myocardial infarction: 0%. In the hypothermia analysis, the pooled proportion of 30-day mortality was 11,6%. The incidence of post-op neurological deficits was 35,4% and good recovery under neurological analysis by GOS was present in 69.2%. CONCLUSION: The use of the three methods is safe and the related complications were very low. Further studies are necessary, especially with comparative analysis, for extended knowledge.

Optimizing surgical approaches for anterior communicating artery aneurysms: Development and internal validation of a novel surgical scoring system.

BACKGROUND: The objective was to provide comprehensive preoperative information on both the aneurysm orientation and the side and method of surgical approach for optimal preoperative information and safe clipping using 3D imaging modalities. This was achieved by making an objective risk assessment on the surgical side/method and evaluating its effectiveness with internal validation. MATERIALS AND METHODS: Radiologic data of 61 ACoA aneurysm patients between 2012 and 2020 were retrospectively analyzed. A scoring system based on five criteria; ACoA aneurysm dome orientation, A1 symmetry/control, perforating artery control, A2 trace orientation, and A2 fork symmetry was developed. The system is designed to align with the most common surgical approaches in ACoA aneurysm surgery. The patients were categorized into three groups based on the scoring results to determine the most appropriate surgical method. Group I was recommended, Group II was less recommended, and Group III was least recommended. Internal validation was performed to assess the system's effectiveness. Outcomes and complication rates were statistically evaluated. RESULTS: When the scoring system was utilized, the mean score difference between the first group and the other groups was 2.71 and 4.62, respectively. There was a homogeneous distribution among the groups in terms of age, sex, WFNS, and Fisher scores. Complication occurred in three patients in Group I and nine patients each in Group II and Group III. The further the deviation from the first option, the higher the complication rate (p = 0.016), and a significant cause-effect relationship was identified (p = 0.021). The ROC curve established a cut-off value of 12.5 points for complications and outcomes. CONCLUSION: Our study introduces a new scoring system for ACoA aneurysms, enhancing the use of 3D CTA in daily practice and providing internal validation for the proposed approach. By evaluating objective criteria, this scoring system helps predict surgical risks, prevent complications, and supports personalized evaluation and selection of the surgical approach based on objective criteria.

An evaluation of physical and augmented patient-specific intracranial aneurysm simulators on microsurgical clipping performance and skills: a randomized controlled study.

OBJECTIVE: In the era of flow diversion, there is an increasing demand to train neurosurgeons outside the operating room in safely performing clipping of unruptured intracranial aneurysms. This study introduces a clip training simulation platform for residents and aspiring cerebrovascular neurosurgeons, with the aim to visualize peri-aneurysm anatomy and train virtual clipping applications on the matching physical aneurysm cases. METHODS: Novel, cost-efficient techniques allow the fabrication of realistic aneurysm phantom models and the additional integration of holographic augmented reality (AR) simulations. Specialists preselected suitable and unsuitable clips for each of the 5 patient-specific models, which were then used in a standardized protocol involving 9 resident participants. Participants underwent four sessions of clip applications on the models, receiving no interim training (control), a video review session (video), or a video review session and holographic clip simulation training (video + AR) between sessions 2 and 3. The study evaluated objective microsurgical skills, which included clip selection, number of clip applications, active simulation time, wrist tremor analysis during simulations, and occlusion efficacy. Aneurysm occlusions of the reference sessions were assessed by indocyanine green videoangiography, as well as conventional and photon-counting CT scans. RESULTS: A total of 180 clipping procedures were performed without technical complications. The measurements of the active simulation times showed a 39% improvement for all participants. A median of 2 clip application attempts per case was required during the final session, with significant improvement observed in experienced residents (postgraduate year 5 or 6). Wrist tremor improved by 29% overall. The objectively assessed aneurysm occlusion rate (Raymond-Roy class 1) improved from 76% to 80% overall, even reaching 93% in the extensively trained cohort (video + AR) (p = 0.046). CONCLUSIONS: The authors introduce a newly developed simulator training platform combining physical and holographic aneurysm clipping simulators. The development of exchangeable, aneurysm-comprising housings allows objective radio-anatomical evaluation through conventional and photon-counting CT scans. Measurable performance metrics serve to objectively document improvements in microsurgical skills and surgical confidence. Moreover, the different training levels enable a training program tailored to the cerebrovascular trainees' levels of experience and needs.

Cortical perfusion measurements with laser speckle contrast imaging during adenosine induced cardiac arrest for aneurysm clipping: a case report.

Adenosine induced cardiac arrest (AiCA) is one of the methods used to facilitate microsurgical aneurysm clipping by providing more visibility and less pressure in the aneurysmal sac and neighboring vessels. We report the use of laser speckle contrast imaging (LSCI) during AiCA to monitor the changes in pulsation and perfusion on the cortical surface during adenosine induced cardiac arrest for aneurysm clipping surgery. Application of this technology for perfusion monitoring may improve workflow and surgical guidance and provide valuable feedback continuously throughout the procedure. ClinicalTrials.gov identifier: NCT0502840.

[Russian study on brain aneurysm surgery: a continuation (RIHA II)]. / Rossiiskoe issledovanie po khirurgii anevrizm golovnogo mozga: prodolzhenie (RIKhA II).

OBJECTIVE: To assess the main performance indicators of neurosurgical departments in surgical treatment of cerebral aneurysms in the Russian Federation. MATERIAL AND METHODS: We analyzed 22 neurosurgical departments (19 regional and 3 federal hospitals) in 2017 and 2021. The study enrolled 6.135 patients including 3.160 ones in 2017 and 2.975 ones in 2021. We studied the features of surgical treatment of cerebral aneurysms in different volume hospitals and factors influencing postoperative outcomes. RESULTS: The number of surgeries for cerebral aneurysms decreased from 2.950 in 2017 to 2.711 in 2021. Postoperative mortality rate was 6.3% and 5.6%, respectively. The number of microsurgical interventions decreased from 60% in 2017 to 48% in 2021. The share of endovascular interventions increased from 40% to 52%, respectively. Endovascular embolization was accompanied by stenting in 55% of cases. Simultaneous revascularization was carried out in 2% of cases. In 2021, the number of patients undergoing surgery in acute period of hemorrhage increased to 70% (in 2017 - 61%). The number of hospitals performing more than 50 surgical interventions for cerebral aneurysms annually increased from 14 in 2017 to 17 in 2021. CONCLUSION: Certain changes in neurosurgical service occurred in 2021 compared to 2017. Lower number of surgical interventions for cerebral aneurysms, most likely caused by the COVID-19 pandemic, is accompanied by lower postoperative mortality. Endovascular interventions and revascularization techniques became more common. The number of surgeries in acute period after aneurysm rupture and hospitals performing more than 50 surgical interventions for cerebral aneurysms annually increased.

Complication of Middle Cerebral Artery Aneurysm Surgery: An M2 Tear at the Neck, Managed with a Salvage M2-to-M2 In Situ Bypass.

An unexpected rupture at the aneurysm neck, with or without adjacent arterial injury or compromise of distal branches during microsurgical clipping, can be a challenging surgical problem to resolve. In this presented case of a neurologically intact 65-year-old woman, elective clipping of an unruptured right middle cerebral artery bifurcation aneurysm was complicated by an unexpected M2 tear at the neck, involving the origin of the frontal M2. Attempts to seal the tear directly, using various techniques, failed; therefore, it was ultimately managed with sacrifice of the vessel and a salvage side-to-side M2-to-M2 in situ bypass. Six months after surgery, the patient demonstrated moderate disability but was able to ambulate with a cane.

Management of Intraoperative Rupture of Intracranial Aneurysms: Agony and Ecstasy.

Intraoperative rupture (IOR) of an intracranial aneurysm is a serious complication, often with catastrophic consequences that are difficult to manage even by the best hands. Like most surgical complications, this one is better to avoid than to treat, but any vascular neurosurgeon should know how to deal with IOR of an aneurysm, because it is bound to occur. The aims of this study were to evaluate the incidence and factors associated with IOR during clipping of intracranial aneurysms, to analyze strategies for controlling hemorrhage in such cases, and to assess outcomes. Overall, 911 cases of intracranial aneurysms, which were treated surgically by the author during 26 years of his professional career, were reviewed. IOR was never noted during clipping of an unruptured intracranial aneurysm (65 cases) but was encountered in 49 of 846 cases (5.8%) presenting with subarachnoid hemorrhage. This complication occurred most often in cases of internal carotid artery aneurysms (22 cases; 45%), followed by anterior communicating artery aneurysms (12 cases; 24%), distal anterior cerebral artery aneurysms (6 cases; 12%), middle cerebral artery aneurysms (6 cases; 12%), and posterior circulation aneurysms (3 cases; 6%). IOR was mostly encountered during early surgery (within 3 days) after the ictus (26 cases; 53%) and most frequently occurred during dissection of the aneurysm (26 cases; 53%). Overall, 22 patients (45%) had good outcome, 18 (37%) had variable morbidity, and 9 (18%) died. Fatal consequences of IOR were noted only in cases of big or multilobulated internal carotid artery aneurysms. Detailed planning of the surgical procedure, application of meticulous microdissection techniques, and anticipation of possible intraoperative incidents during intervention aimed at clipping of an intracranial aneurysm can reduce the risk of IOR, as well as the associated morbidity and mortality.

Enhance Safety in Aneurysm Surgery: Strategies for Prevention of Intraoperative Vascular Complications.

Complications during surgery for intracranial aneurysms can be devastating. Notorious pitfalls include premature rupture, parent vessel occlusion, local cerebral injury and brain contusion, and incomplete neck obliteration. These unfavorable intraoperative events can result in major neurological deficits with permanent morbidity and even mortality. Herein, the author highlights the relevant surgical strategies used in his daily practice of aneurysm surgery (e.g., aneurysm clipping with adenosine-induced temporary cardiac arrest), application of which may help prevent vascular complications and enhance surgical safety through reduction of the associated risks, thus allowing improvement of postoperative outcomes. Overall, all described methods and techniques should be considered as small pieces in the complex puzzle of prevention of vascular complications during aneurysm surgery.

How I do it: the endoscopic endonasal transclival approach for clipping of the ruptured vertebral artery aneurysm.

BACKGROUND: Vertebral artery aneurysms account for less than 5% of all cerebral aneurysms. They have a high risk of rupture and are associated with threatening clinical outcomes compared with anterior circulation aneurysms. METHOD: The endoscopic endonasal transclival approach (EETA) was used. During the temporary clipping, the neck of the aneurysm was dissected, and a permanent clip was applied. The repair of the skull base defect was carried out with the nasoseptal mucoperiosteal flap on the vascular pedicle. CONCLUSION: The EETA is a feasible alternative for the clipping of the medially located ruptured vertebral artery aneurysm. EETA can be recommended for centers with a large volume of cerebrovascular and endoscopic neurosurgical procedures.

Comparative outcomes of the treatment of unruptured paraophthalmic aneurysms in the era of flow diversion.

BACKGROUND: Paraophthalmic aneurysms present a challenge to surgeons and their ideal management remains up for debate. We studied recent outcomes of these lesions in a single center. METHODS: A retrospective chart review of all patients undergoing treatment for paraophthalmic aneurysms from 2017-2019 was performed. Factors including patient demographics, aneurysm characteristics, treatment modality, radiographic treatment outcome, clinical outcome, and length of stay were collected, and bivariate analysis was performed. RESULTS: In total 84.5% (82/97) of aneurysms were treated endovascularly and 15.5% (15/97) surgically. In the surgery cohort, there were three transient perioperative complications (20%) and one minor postoperative complication (6.7%). Complete aneurysm occlusion or near complete (<2mm residual) was achieved in 100% (15/15). All but one patient had mRS ≤1 at the last follow-up. In the endovascular group, 78.1% (64/82) underwent flow diversion alone. Endovascular treatment was associated with a 4.9% (4/82) rate of periprocedural complications: 3 transient events, and 1 death, and a 3.7% (3/82) rate of delayed complications: 2 transient vision changes, and one death. Rate of total occlusion was 87.8% (72/82). 76 patients (92.7%) had mRS ≤1 at the last follow-up. Length of stay was significantly shorter in the endovascular group (3.4 days vs. 7.0 days) [p < 0.001]. CONCLUSIONS: This series demonstrates similar safety to previously reported series as well as the efficacy of both surgical clipping and endovascular embolization of paraophthalmic aneurysms. Rate of complications and treatment efficacy were similar in both groups although this represents a single institution series not generalizable to all centers.

Comorbidities and Medical Complications in Hospitalized Subarachnoid Hemorrhage Patients.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (SAH) remains a devastating condition with a case fatality of 36% at 30 days. Risk factors for mortality in SAH patients include patient demographics and the severity of the neurological injury. Pre-existing conditions and non-neurological medical complications occurring during the index hospitalization are also risk factors for mortality in SAH. The magnitude of the effect on mortality of pre-existing conditions and medical complications, however, is less well understood. In this study, we aim to determine the effect of pre-existing conditions and medical complications on SAH mortality. METHODS: For a 25% random sample of the Greater Montreal Region, we used discharge abstracts, physician billings, and death certificate records, to identify adult patients with a new diagnosis of non-traumatic SAH who underwent cerebral angiography or surgical clipping of an aneurysm between 1997 and 2014. RESULTS: The one-year mortality rate was 14.76% (94/637). Having ≥3 pre-existing conditions was associated with increased one-year mortality OR 3.74, 95% CI [1.25, 9.57]. Having 2, or ≥3 medical complications was associated with increased one-year mortality OR, 2.42 [95% CI 1.25-4.69] and OR, 2.69 [95% CI 1.43-5.07], respectively. Sepsis, respiratory failure, and cardiac arrhythmias were associated with increased one-year mortality. Having 1, 2, or ≥3 pre-existing conditions was associated with increased odds of having medical complications in hospital. CONCLUSIONS: Pre-existing conditions and in-hospital non-neurological medical complications are associated with increased one-year mortality in SAH. Pre-existing conditions are associated with increased medical complications.

Traumatic intracranial aneurysms (TICA) in children: a description of two clinical cases of successful treatment and review of literature.

OBJECTIVE: Traumatic intracranial aneurysms (TICA) across all age groups make up less than 1% of all aneurysms. Traumatic aneurysms in children occur from 10 to 39%, and their treatment requires special considerations. Even though readily diagnosed, the management of traumatic intracranial aneurysms in children is still a subject for discussion. Two cases of traumatic aneurysms following penetrating and blunt trauma are presented. CASE DESCRIPTION: Two cases of traumatic aneurysms are presented. The first patient presented with an aneurysm of the distal M4 segment of the left middle cerebral artery (MCA) 1 week following blunt traumatic brain injury with skull fractures. The aneurysm was excised without complications. The second patient presented with a saccular aneurysm of the A2 segment of the left anterior cerebral artery (ACA) following penetrating traumatic brain injury with a metal rod. The aneurysm was discovered incidentally on computed tomography angiography (CTA) performed to exclude a brain abscess when the patient developed a persistent fever. After numerous unsuccessful attempts at endovascular embolization, microsurgical aneurysm clipping was performed without complications. CONCLUSION: Traumatic intracerebral aneurysms are relatively more common in childhood. They commonly occur in the first 21 days post-trauma but can also occur in the late period. We, therefore, recommend that CTA or direct cerebral angiography should be performed within the first 3 weeks to exclude TICA and in all patients with sudden deterioration in the early postoperative period. Considering the high mortality rate associated with conservative management, surgical and/or endovascular management should be performed once the diagnosis is made.

Left middle cerebral artery M1-2 segment dissecting aneurysm resection and reanastomosis under double-barrel STA-MCA bypass protection.

BACKGROUND: Middle cerebral artery (MCA) M1-related dissecting aneurysms involving the M1 segment are difficult because of the involvement of M1 perforators and the short duration of ischemia tolerance during bypass. METHOD: We report a case of MCA M1-2 dissecting aneurysm resection and reanastomosis under bypass blood flow protection. Histological staining was used to show aneurysm pathological characteristics. CONCLUSION: This case demonstrates the value of distal bypass for blood flow protection in MCA M1-2 dissecting aneurysm dissection and reanastomosis. Pathological staining showed intramural thrombus, cell dysfunction, microtube formation, and obvious inflammation.

Adverse intraoperative events during surgical repair of ruptured cerebral aneurysms: a systematic review.

Compared with endovascular techniques, clipping of ruptured cerebral aneurysms has been shown to associate with increased morbidity in several studies. Despite this, clipping remains the preferred option for many aneurysms. The objective of this study is to describe the reported adverse events of open repair of ruptured cerebral aneurysms and their impact on patient outcome. The PubMed, Embase and Cochrane databases were searched between June 1999 and June 2019 to identify original studies of at least 100 patients undergoing surgical repair of ruptured cerebral aneurysms and in which adverse event rates were reported. Thirty-six studies reporting adverse events in a total of 12,410 operations for repair of ruptured cerebral aneurysms were included. Surgical adverse events were common with 36 event types reported including intraoperative rupture (median rate of 16.6%), arterial injury (median rate of 3.8%) and brain swelling (median rate 5.6%). Only 6 surgical events were statistically shown to associate with poor outcomes by any author and for intraoperative rupture (the most frequently analysed), there was an even split between authors finding a statistical association with poor outcome and those finding no association. Even with modern surgical techniques, the technical demands of surgical aneurysm repair continue to lead to a high rate of intraoperative adverse events. Despite this, it is not known which of these intraoperative events are the most important contributors to the poor outcomes often seen in these patients. More research directed towards identifying the events that most drive operative morbidity has the potential to improve outcomes for these patients.

Anatomic feasibility of endoscopic endonasal intracranial aneurysm clipping: a systematic review of anatomical studies.

Clinical studies have suggested the endoscopic endonasal approach (EEA) for aneurysm clipping as a feasible way to treat select intracranial aneurysms. Among neurosurgery, there is not a consensus on the utility of EEA aneurysm clipping. This review aims to define the anatomic feasibility of EEA for aneurysm clipping. Two databases (PubMed, Cochrane) were searched for anatomical studies assessing EEA for intracranial aneurysm clipping. Literature review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Quantitative anatomical studies were included. Eleven studies met inclusion criteria. Vascular exposure and clip placement on vessels of interest were possible, although only one study assessed these parameters with physical aneurysm models. Anterior circulation vessels, although accessible in over 90% of specimens, had low successful clipping rates in a small and large aneurysm models. Small and large model posterior circulation aneurysms were more readily clipped. Proximal and distal controls were readily attainable in posterior circulation aneurysms, but not anterior. This current literature review highlights the relevance of anatomical studies in assessing the feasibility of the EEA for clipping intracranial aneurysms. As such, anterior circulation aneurysms are poor candidates for EEA given difficulties in clip placement and obtaining proximal control and distal control in small and large aneurysms. While our results suggest that clipping of posterior circulation aneurysms is feasible from a technical stand of view, further clinical experience is required to assess its feasibility in terms of safety and efficacy, balancing the indications with endovascular treatment options.

Frequency and risk factors for postoperative aneurysm residual after microsurgical clipping.

OBJECTIVE: Aneurysm residuals after clipping are a well-known problem, but the course of aneurysm remnants in follow-up is not well studied. No standards or follow-up guidelines exist for treatment of aneurysm remnants. The aim of this study was to evaluate the risk factors for postoperative aneurysm remnants and their changes during follow-up. METHODS: We performed a retrospective analysis of 666 aneurysms treated via clipping in our hospital from 2006 to 2016. Postoperative and follow-up angiographic data were analyzed for aneurysm remnants and regrowth. Clinical parameters and aneurysm-specific characteristics were correlated with radiological results. RESULTS: The frequency of aneurysm residuals was 12% (78/666). Aneurysms located in the middle cerebral artery (p = 0.02) showed a significantly lower risk for incomplete aneurysm occlusion. Larger aneurysms with a diameter of 11-25 mm (p = 0.005) showed a significantly higher risk for incomplete aneurysm occlusion. Five patients underwent re-clipping during the same hospital stay. Remnants were stratified based on morphological characteristics into "dog ears" (n = 60) and "broad based" (n = 13). The majority of the "dog ears" stayed stable, decreased in size, or vanished during follow-up. Broad-based remnants showed a higher risk of regrowth. CONCLUSIONS: A middle cerebral artery location seems to lower the risk for the incomplete clip occlusion of an aneurysm. Greater aneurysm size (11-25 mm) is associated with a postoperative aneurysm remnant. The majority of "dog-ear" remnants appear to remain stable during follow-up. In these cases, unnecessarily frequent angiographic checks could be avoided. By contrast, broad-based residuals show a higher risk of regrowth that requires close imaging controls if retreatment cannot be performed immediately.

How I do it: coil extraction and clip reconstruction of a previously coiled giant middle cerebral artery aneurysm.

BACKGROUND: Microsurgical clipping of previously coiled intracranial aneurysms can be technically challenging. We present the case of a 48-year-old female with a partially coiled, previously ruptured giant middle cerebral artery aneurysm and the associated technical nuances. METHODS: We performed a successful coil extraction and clip reconstruction of this aneurysm using an ultrasonic aspirator and stacked fenestrated aneurysm clips. CONCLUSION: Coil extraction and clip occlusion of previously coiled intracranial aneurysms is a complex and technically challenging procedure but can be performed safely and effectively when employed judiciously.

256-row multislice CT angiography in the postoperative evaluation of cerebral aneurysms treated with titanium clips: using three-dimensional rotational angiography as the standard of reference.

OBJECTIVE: To assess the diagnostic accuracy of 256-row multislice computed tomographic angiography (CTA) compared with three-dimensional rotational angiography (3DRA) in the postoperative evaluation of cerebral aneurysms treated with titanium clips. METHODS: A total of 128 patients (42 men, 86 women; mean age, 57.6 years) with 143 cerebral aneurysms treated using titanium clips underwent both CTA and 3DRA. Two reviewers retrospectively evaluated the following parameters on CTA and 3DRA: (1) residual/recurrent aneurysm (absent or present), (2) patency of parent artery (patent or occluded/severe stenotic (> 70%)), and (3) patency of adjacent branch (patent or occluded/absent). RESULTS: A total of 24 residual/recurrent aneurysms were detected by 3DRA. The sensitivity, specificity, and accuracy of CTA for the detection of residual/recurrent aneurysms were 83.3%, 100%, and 97.2% for reviewer 1 and 79.2%, 100%, and 96.5% for reviewer 2, respectively. The sensitivity, specificity, and accuracy of CTA for the evaluation of patency of parent artery were 100%, 100%, and 100%, respectively, for both reviewers. The sensitivity, specificity, and accuracy of CTA for evaluation of the patency of adjacent branch were 85.1%, 100%, and 92.3% for reviewer 1 and 82.4%, 100%, and 90.9% for reviewer 2, respectively. CONCLUSION: A 256-row multislice CTA is a valuable non-invasive tool for assessment of cerebral aneurysms treated with titanium clips. KEY POINTS: • A 256-row multislice CTA is an accurate imaging technique for the postoperative assessment of cerebral aneurysms treated with titanium clips. • Sensitivity of CTA for the detection of residual/recurrent aneurysms was 79-83% compared with 3DRA. • CTA is still limited in detecting residual/recurrent aneurysms of < 2 mm and small adjacent branches.

How I do it: lateral supra-cerebellar infra-tentorial approach for P2-P3 junction cerebral aneurysms.

BACKGROUND: P2-P3 junction aneurysms are challenging to treat surgically because of their frequent complex morphology and their location deep in close proximity to the midbrain. The sub-temporal route requires significant retraction of the temporal lobe in addition to potential injury to the vein of Labbe. We describe the technique for treating such aneurysms via a lateral supra-cerebellar infra-tentorial (LSCIT) approach, which eliminates manipulation of the temporal lobe. METHOD: Cadaveric dissection provided comprehensive understanding of relevant anatomy. Intraoperative video shows clipping of the aneurysm using a LSCIT approach. CONCLUSION: LSCIT approach allows safe clipping of P2-P3 aneurysms with minimal brain manipulation.