Intraoperative Rupture Rate Research Articles

Comparative Analysis of Tailored Minicraniotomy versus Standard Pterional Craniotomy in the Treatment of Anterior Circulation Aneurysms: A Single-Center Case–Control Observational Study

Abstract Introduction Multiple minicraniotomies (Mct) have been proposed as alternatives to standard pterional craniotomy (Pct) for intracranial aneurysm treatment. These approaches offer limited surgical corridors and distinct working angles, posing challenges in addressing all aneurysm types with one method. We suggest a tailored Mct technique, comprising three minimally invasive approaches targeting anterior circulation aneurysm sites (middle cerebral artery, internal carotid artery, anterior communicating artery). Methods We conducted a retrospective, case–control study at a single center comparing Pct and Mct outcomes for ruptured and unruptured aneurysms. Parameters evaluated included conversion rates to Pct or decompressive hemicraniectomy (DHC), intraoperative rupture (IOR), surgical complications, complete aneurysm exclusion, 6-month modified Rankin Scale (mRS) scores, and aesthetic outcomes using a visual analog scale. A total of 146 patients were included, with 103 in the Mct group and 43 in the Pct group, comparable in mean age, sex, and aneurysm topography. Hunt–Hess scores and Fisher grades were lower in the Mct group initially. Results No cases required conversion from Mct to Pct or DHC. No significant differences were observed in IOR, surgical complications, and aneurysm exclusion rates between groups. The Mct group demonstrated better 6-month mRS scores and aesthetic outcomes. Conclusion Our study indicates that tailored Mct is as safe and effective as standard Pct for intracranial aneurysms, with significant cosmetic benefits. Thus, tailored Mct can be considered a valuable alternative not only to Pct but also to other minimally invasive surgical methods for these aneurysms.

Anterior Communicating Artery Aneurysms: Surgical Strategy and Outcome based on Proposed Newer Classification

Background: The ruptured anterior communicating artery aneurysm is the most frequent intra-cranial aneurysm treated at any neurosurgical department. These aneurysms arise from either the A1-A2-Acom artery junction or Acom artery. The surgical outcome depends on the age of the patient, time duration between ictus and surgery, and Hunt and Hess grade at admission. In this article, we intend to analyze the surgical outcome based on our proposed classification with our overall experience of Acom aneurysm. Methods: A retrospective review of our surgical database with 250 patients of ruptured Acom was done, and the location, morphology, and direction of aneurysm, along with other clinical parameters including the demographic profile, radiological findings, and intra-operative details, were studied. We classified the Acom based on both site of origin and morphology (Type I, junctional on the dominant side; Type II, fusiform with an ill-defined neck and branching pattern; Type III, saccular true Acom A) and secondarily as described in the literature on the basis of the direction of fundus (Type A–E). The clinical parameters were compared among the above groups using Fischer-exact and one-way analysis of variance test. Results: A total of 250 patients (M: F =113:137) were included (mean age 52.1 ± 11.5 standard deviation years). 55.2% patients had left A1 dominance. Type I Acom A was commonly found on the left dominant circulation (P = 0.00). The difference in aspect ratio of Type I (2.0 ± 0.8) and Type II (1.8 ± 0.52) aneurysms was insignificant (P = 0.28). However, a significant difference in post-operative vasospasm among different types of aneurysms was found (P < 0.05). The Type I Acom A were anteriorly directed, while Type II and III were posteriorly directed (P = 0.001). The mean follow-up of the study was 44.4 ± 25.7 months, with age (P = 0.007) and Hunt and Hess grade (P = 0.001) at admission correlating with surgical outcome. Conclusion: Classifying the Acom A pre-operatively based on site and morphology, location, and direction of fundus helps in surgical planning and prognosis. The junctional ‘Type IA aneurysms’ are most common and possess a high intra-operative rupture rate. The anteriorly directed aneurysms have a better prognosis, and visual complaints are usually associated with anterior-inferiorly directed aneurysms.

Abstract 113: Treatment of Tiny (≤ 3mm) Unruptured Middle Cerebral Artery Aneurysms Are Associated With High Risk of Procedural Complications: An Analysis of the Neurovascular Quality Initiative-Quality Outcomes Database

Introduction: Improved imaging modalities have led to an increased detection of intracranial aneurysms, many of which are small. While studies have shown that many ruptured intracranial aneurysms are small (≤7 mm), the natural history of tiny (≤3 mm) aneurysms, particularly in certain locations such as the middle cerebral artery (MCA) is thought to be relatively benign with a reported rupture rate of less than 0.5% per year. The objective of this study is to evaluate the safety and efficacy of treatment of tiny unruptured MCA aneurysms. Methods: The NVQI-QOD registry was queried for patients with tiny unruptured MCA aneurysms who underwent either microsurgical or endovascular repair. Tiny size was defined as an aneurysm with a maximum dimension of ≤3 mm. Demographics, aneurysm characteristics and treatment safety were queried. Safety data included intra-operative and post-operative complications. Outcomes included modified Rankin Score (mRS) at discharge and last follow up as well as aneurysm occlusion status at discharge. Results: Of 670 treated, unruptured MCA aneurysms, 43 were tiny (6.4%). The mean aneurysm width was 1.9 mm with a mean patient age of 56.3 years. The median pre-operative mRS was 0 (range 0-4). The majority of patients underwent microsurgery (27/43). The overall intra-operative complication rate was 7% (3/43) with an intra-operative rupture rate of 4.7% (2/43). The post-operative complication rate was 9.3% (4/43). New intracerebral hemorrhage occurred in 7% of patients (3/43) and unplanned return to OR occurred in 14.8% of patients who underwent microsurgery (4/27). There were no mortalities. 16.3% (7/43) of patients were discharged to inpatient rehabilitation or a skilled nursing facility. At discharge, 37 (88.1%) patients had complete aneurysm occlusion. In the subgroup of patients with recorded follow up data, only 40% (10/25) had a mRS of 0 at discharge and 40% (6/15) had an mRS of 0 at last follow up (median follow up: 165 days). Conclusions: Our analysis showed that treatment of tiny unruptured MCA aneurysms is associated with a high rate of complications. We suggest that many tiny, unruptured MCA aneurysms should be observed given that the morbidity associated with treatment is likely significantly higher than the risk of rupture.

Giant Aneurysms: Not So Giant in Behavior.

Giant intracranial aneurysms (GIAs) are very complex in their behavior and treatment procedure. There are various modalities of treatment. The annual rupture rate of GIA (6%) is higher than that of small aneurysms (1-3%). Neurosurgeons handle these aneurysms during operations. We tried to analyze the intraoperative rupture rate (IRR) of GIA in relation to small aneurysms. IRR is concerned with the rupture of the aneurysms during operative handling. For conducting the study, we compared the IRR of 7 GIAs and 45 small aneurysms during a span of 10 years. All the operations were performed by the same team and the same principal surgeon. IRR was compared by statistical analysis. Z-test was done to compare the two rates: Z = 0.68 and P = 0.49. According to our study, the IRR of GIA is not statistically different from small aneurysms. The IRR of GIA is not higher because of three factors which we have analyzed: 1) layers of intraaneurysmal thrombus, 2) fibrin deposition on the aneurysm wall, and 3) blocked neck of the aneurysm by thrombus. The IRR of GIA is not different from small aneurysms.

Endoscopic Eyebrow Approach for Aneurysms.

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. 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. 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.

Is laparoscopic approach feasible in early-stage ovarian cancer? A retrospective study in single tertiary center.

e17560 Background: Laparoscopic approach for early-stage ovarian cancer is a controversy. Current studies showed no negative impacts on these patients. However, some limitations were noted, such as small case numbers, heterogeneity, and retrospective study. Methods: We retrospectively reviewed our cases who was diagnosed as early-stage ovarian cancer and received staging surgery from 2009 through 2017. There patients were divided into two groups, via laparoscopic staging or laparotomy. The primary outcome was progression-free survival. The secondary outcomes were overall survival and intra-operative rupture rate. We performed the Kaplan-Meier method and chi-square test for analyzing survival outcome and factors, in order to evaluate impacts on different surgical methods. Results: Total 520 patients (2014 FIGO stage IA-IC3) were enrolled, including 355 patients who underwent open surgery and 165 patients who underwent laparoscopic surgery. The median follow-up time for survivors was 71(range,39.7-102.3）months. The progression-free survival was similar between two groups and all subgroups. The overall survival was also similar between two surgical methods and all subgroups, except subgroup of clear cell carcinoma. The p-value of overall survival in clear cell carcinoma patients was 0.05. However, the case numbers of clear cell carcinoma 81 in laparotomy group and 31 in laparoscopy group, respectively. The intra-operative rupture rate was increased in laparoscopic group. The relative risk and p-value were 1.139 and 0.043, respectively. Conclusions: Laparoscopic may be feasible in early-stage ovarian cancer in selected patients and expert surgeon due to higher intra-operative rupture rate. If clear cell carcinoma of ovary was highly suspected, the surgeon should be alerted because poorer overall survival in clear cell carcinoma of ovary patients was observed.

Laparoscopically assisted ovarian cystectomy with totally enclosed protective device for tumor isolation.

To present a novel totally enclosed protective device for tumor isolation in laparoscopic ovarian cystectomy. A retrospective study was conducted of 16 patients with unilateral ovarian teratoma in the Department of Obstetrics and Gynecology of the China-Japan Friendship Hospital. Laparoscopic surgery was performed with a totally enclosed protective device for tumor isolation, followed by a case series retrospective study. The indexes measured included size of cyst, rate of intraoperative rupture, duration of operation, amount of intraoperative blood loss, and postoperative length of stay in the hospital. An intact cyst resected in the device with no spillage seen indicated a successful surgery. A total of 16 operations were performed successfully. The mean diameter of the cysts was 7.2 ± 1.4cm. Of them, 12 (75%) had an intraoperative cyst rupture without spillage. The mean duration of surgery was 1.3 ± 0.1h and the mean amount of intraoperative blood loss was 12.5 ± 3.2ml. All postoperative histology tests showed benign cysts. The mean length of stay after surgery was 2.4 ± 0.5 days. No peritonitis-related symptoms or complaints were reported. Laparoscopically assisted ovarian cystectomy with a totally enclosed protective device for tumor isolation was confirmed safe and feasible.

The Lateral Supraorbital Craniotomy Approach for Anterior Circulation Aneurysms: A Modern Surgical Case Series in the Endovascular Era

The lateral supraorbital (LSO) approach is a minimally invasive modification of the standard pterional approach to anterior circulation aneurysms. This study aimed to describe a dual-trained cerebrovascular neurosurgeon's first 18-month experience with the LSO approach, including decision-making criteria and lessons learned. This retrospective case series analyzed 50 consecutive patients treated with LSO craniotomy for aneurysm clipping by a single surgeon. Aneurysms were separated into 3 categories by location: internal carotid artery, anterior communicating artery, and middle cerebral artery. Surgical characteristics were evaluated for differences by location and rupture status. Aneurysm clipping via LSO was performed on 57 aneurysms in 50 patients. Fixed retraction was employed less often in patients with internal carotid artery aneurysms than in patients with anterior communicating artery, middle cerebral artery, or multiple aneurysms (10% vs. 68.2%, 45.5%, and 42.9, P= 0.02). Of patients, 26 (52%) presented with subarachnoid hemorrhage; the majority of patients (92.3%) had Hunt and Hess grade I-III. No differences were noted in intraoperative rupture rates, fixed retractor use, operative duration, or estimated blood loss by rupture status. Adverse events included permanent frontalis nerve palsy in 1 patient (2%), temporalis atrophy in 1 patient, and transient aphasia in 1 patient. No postoperative hematomas or strokes were observed. The LSO approach can safely and effectively treat anterior circulation aneurysms and should be considered a viable minimally invasive option for aneurysm clipping. Further studies comparing the LSO approach with other cranial approaches are needed.

126 Neurosurgical Clipping Versus Endovascular Coiling for Unruptured and Ruptured Distal Anterior Cerebral Artery Aneurysms: A Systematic Review and Meta-Analysis

Abstract Aim To assess outcomes after clipping or coiling of distal anterior cerebral artery (DACA) aneurysms via a meta-analysis. Method Systematic searches of Medline, Embase and Cochrane Central were undertaken from 1st January 1973 until 1st May 2020 for published studies reporting microsurgical clipping and endovascular coiling of DACA aneurysms. Primary outcome measure was independent functional outcome (modified Rankin scale (mRS) 0–2, or Glasgow Outcome Scale (GOS) 4–5). Secondary outcomes were poor clinical outcome and mortality, perioperative complications, aneurysm occlusion rates, rebleeding and recurrence. Results 938 and 223 patients with ruptured and unruptured DACA aneurysms, respectively, were reported across 28 studies. Pooled rate of procedure-related morbidity was 6.8% (95%CI: 3.2 – 11.2) and 1.3% (95%CI: 0.0 – 9.1) for clipped and coiling ruptured DACA aneurysms respectively. Pooled rate of intraoperative rupture for clipped and coiled ruptured DACA aneurysms was 10.0% (95%CI: 2.5 – 20.6) and 5.7% (95%CI: 1.1 – 12.5) respectively. Pooled rate of acute hydrocephalus for clipped and coiled ruptured DACA aneurysms was 7.8% (95%CI: 0.5 – 19.7) and 1.4% (95% CI: 0.0 – 11.3) respectively. Pooled rate of perioperative mortality was 0.002% (95% CI: 0.0 – 0.7) ruptured DACA aneurysms treated by clipping. For clipped unruptured DACA aneurysms, pooled rates of procedure-related morbidity, intraoperative rupture, acute hydrocephalus were 2.5% (95%CI: 0.0 – 7.5), 0.002% (95%CI: 0.0 – 3.1) and 0.5% (95%CI: 0.0 – 5.1) respectively. Conclusions Clipping results in poorer short-term outcomes when compared to coiling. However, the final decision-making should be shared with the patient and be performed on a selective, case-by-case basis in order to maximize patient benefits.

Woven EndoBridge device for the treatment of ruptured intracranial aneurysms: A systematic review of clinical and angiographic results.

The clinical outcome and angiographic outcome data of Woven EndoBridge (WEB) device for the treatment of ruptured intracranial aneurysms (IAs) are limited. We conducted a meta-analysis of the latest literature on the WEB device in the treatment of ruptured IAs. A comprehensive literature search of 4 databases (PubMed, Web of Science, Cochrane library, and Embase) was conducted for studies published from January 1, 2010 to December 31, 2020. Two reviewers independently extracted variables (aneurysm and patient characteristics) using a prespecified data-collection sheet. Outcomes studied included initial and latest follow-up angiographic outcomes, technical success rate, perioperative mortality, retreated rate, perioperative re-bleeding, complication, intraoperative rupture, favorable neurologic outcome at discharge. We used random-effects model to pool the data. We finally presented the results of 7 articles including 276 patients with 283 aneurysms. Initial complete and adequate occlusion rate were 38% (95% CI, 25%-50%) and 98% (95% CI, 95%-100%), respectively. Latest follow-up complete and adequate occlusion rate were 61% (95% CI, 46%-75%) and 91% (95% CI, 84%-98%), respectively.Technical success rate was 99% (95% CI, 98%-100%). Perioperative mortality rates and perioperative re-bleeding rate were 9% (95% CI, 3%-15%) and 1% (95% CI, 0%-2%), respectively. Retreated rate was 6% (95% CI, 3%-10%). Overall and WEB treatment-related thromboembolic complication was 10% (95% CI, 6%-13%) and 7% (95% CI, 2%-12%), respectively. Intraoperative rupture rate was 3% (95% CI, 0%-6%). Endovascular treatment of ruptured IAs with the WEB device has a good safety profile and an acceptable aneurysm occlusion rate.

Intraoperative Aneurysm Rupture: Surgical Experience and the Rate of Intraoperative Rupture in a Series of 1000 Aneurysms Operated on by a Single Neurosurgeon

This study aims to examine the risk factors that can cause intraoperative rupture (IOR), and especially, the role of surgical experience. To our knowledge, this is the first study to analyze the effect of the surgeon's experience on the IOR rate in 2 different perspectives. A total of 1000 aneurysms in 775 patients were operated on by a single neurosurgeon. The clinical and radiologic data and intraoperative video recordings of all patients were retrospectively analyzed. To evaluate the role of the surgeon's experience on the IOR rate, the aneurysms were divided chronologically into both 5-year periods and each 100 aneurysms. Number, stage, severity, location, management of IORs, and patients' outcomes were determined. IOR occurred in 55 aneurysms (5.5% per aneurysm). The incidence of IOR decreased gradually in the first 2 groups of 5-year periods (11.4% and 5.9%, respectively). However, in the last 3 groups, the decline remained stable (4%-5%). Considering all groups, this decrease was statistically significant (P= 0.037). When this evaluation was made for each group of 100 aneurysms, similar results were obtained. Mortality also gradually decreased over the years (P= 0.035). Of 8 possible risk factors, rupture status was found to be the only independent predictor for IOR (OR, 8.68; 95% confidence interval, 3.69-20.47; P <0.001). Increased surgical experience reduces the IOR rate from 10%-11% to 4%-5% after an average of 250 aneurysm operations. However, this rate does not decrease further with more experience. To our knowledge, a learning curve regarding IOR is presented for the first time in the literature.

Impact of aneurysm shape and neck configuration on cerebral infarction during microsurgical clipping of intracranial aneurysms.

Cerebral infarction is a significant cause of morbidity and mortality related to microsurgical clipping of intracranial aneurysms. The objective of this study was to determine the impact of aneurysm shape and neck configuration on cerebral infarction after aneurysm surgery. The authors retrospectively reviewed consecutive cases of ruptured and unruptured aneurysms treated with microsurgical clipping at their institution between 2010 and 2018. Three-dimensional reconstructions from preoperative computed tomography and digital subtraction angiography were used to determine aneurysm shape (regular/complex) and neck configuration (regular/irregular). Morphological and procedure-related risk factors for cerebral infarction were identified using univariate and multivariate statistical analyses. Among 243 patients with 252 aneurysms (148 ruptured, 104 unruptured), the overall cerebral infarction rate was 17.1%. Infarction tended to occur more often in aneurysms with complex shape (p = 0.084). Likewise, aneurysms with an irregular neck had a significantly higher rate of infarction (37.5%) than aneurysms with regular neck configuration (10.1%, p < 0.001). Aneurysms with an irregular neck were associated with a higher rate of intraoperative rupture (p = 0.003) and temporary parent artery occlusion (p = 0.037). In the multivariate analysis, irregular neck configuration was identified as an independent risk factor for infarction (OR 4.2, 95% CI 1.9-9.4, p < 0.001), whereas the association between aneurysm shape and infarction was not significant (p = 0.966). Irregular aneurysm neck configuration represents an independent risk factor for cerebral infarction during microsurgical clipping of both ruptured and unruptured aneurysms.

Purse-string suture technique using a mini-Pfannenstiel incision to treat large dermoid cysts

This study describes the purse-string suture technique using a mini-Pfannenstiel incision for the surgical treatment of large ovarian dermoid cysts. We investigated intra and postoperative outcomes in 24 patients who underwent removal of large ovarian dermoid cysts through a mini-Pfannenstiel incision using the purse-string suture technique. The surgical procedure was performed by two experienced surgeons. The mean diameter of the cysts was 11.9 cm. The mean operation time was 46 min and the intraoperative rupture rate was 8.3%. No patient developed chemical peritonitis. The length of hospitalisation was 36 h. The recurrence rate was 8.3% in the same ovary at 1-year follow-up. In conclusion, ovarian dermoid cysts measuring >8 cm in diameter can be effectively treated through a mini-Pfannenstiel incision using the purse-string suture technique.Impact StatementWhat is already known on this subject? Dermoid cysts are the most common ovarian germ cell tumours occurring in the second and third decades of life, and these tumours are usually treated surgically. There is a lack of consensus among gynaecologists regarding the optimal surgical treatment modalities for ovarian dermoid cysts; however, laparoscopic cystectomy is the gold standard for the surgical treatment of dermoid cysts. Notably, aspiration of dense cystic contents may be difficult during laparoscopic cystectomy.What do the results of this study add? Our technique enables easy removal of dense cystic materials including hair and bone fragments. The short operation time, low recurrence rate and the minimal incisional scar serve as advantages of our novel method.What are the implications of these findings for clinical practice and/or further research? This surgical technique can be successfully used in clinical settings with limited facilities for laparoscopic surgery.

Ruptured Fisher grade 3 blister aneurysms have a higher incidence of delayed cerebral ischemia than ruptured Fisher grade 3 saccular aneurysms.

BACKGROUND:Blister aneurysms are a rare subclass of aneurysms, which remain challenging to treat both with open cerebrovascular and endovascular techniques, and clinicians continue to see poor outcomes in some cases despite improvements in technology. Based on our clinical observations, we hypothesized that patients with a Fisher grade 3 subarachnoid hemorrhage (SAH) from a ruptured anterior circulation blister aneurysm are significantly more likely to develop poor outcome due to delayed cerebral ischemia than patients with a Fisher grade 3 SAH from a ruptured anterior circulation saccular aneurysm.METHODS:In this consecutive case series, we reviewed management, outcomes, and rates of delayed cerebral ischemia for all ruptured anterior circulation blister aneurysms from 2012 to 2018 at our institution and compared them to a concurrent cohort of ruptured saccular anterior circulation aneurysms. A blister aneurysm was defined as an aneurysm that arises from a nonbranching point and demonstrates hemispherical anatomy on diagnostic angiography.RESULTS:We identified 14 consecutive ruptured anterior circulation blister aneurysms. Thirteen aneurysms were treated operatively– 5 with clip remodeling and 8 with flow diversion embolization. While clip remodeling had a high intraoperative rupture rate (80%), there was only one (12.5%) intraoperative rupture with flow diversion embolization. Outcomes were worsened by delayed cerebral ischemia from vasospasm in patients with Fisher 3 hemorrhages from blister aneurysms (86%). The rate of delayed cerebral ischemia from vasospasm was significantly higher for ruptured blister aneurysms than for a concurrent cohort of ruptured saccular aneurysms (8.6%, P = 0.0001).CONCLUSION:Ruptured Fisher grade 3 anterior circulation blister aneurysms have a significantly higher incidence of delayed cerebral ischemia from vasospasm compared to saccular aneurysms, regardless of the treatment modality.

Impact of Aneurysm Shape on Intraoperative Rupture During Clipping of Ruptured Intracranial Aneurysms

Irregular shape is a known risk factor of intracranial aneurysm rupture causing subarachnoid hemorrhage. The objective of this study was to determine the impact of aneurysm shape on intraoperative rupture (IOR) during microsurgical clipping of ruptured aneurysms. This is a retrospective, single-center study of consecutive patients that underwent clipping between 2010 and 2017. Based on 3-dimensional reconstructions from preoperative computed tomography scan and digital subtraction angiography, aneurysm shape was classified as regular aneurysm (RA) or irregular aneurysm (IRA). Risk factors for IOR were identified using univariate and multivariate statistical analyses. A total of 138 patients with 32 RAs and 102 IRAs were included in the analysis. IRAs had a larger size than RAs (8.3 ± 3.5 vs. 4.6 ± 2.3 mm, respectively; P<0.001). There were 36 instances of IOR (26.1%). The IOR rate was greater in IRAs than in RAs (31.1% vs. 9.4%, respectively; P= 0.02). In multivariate analysis, IRA shape was the only significant independent risk factor for IOR (odds ratio, 3.9; 95% confidence interval, 1.0-14.6; P=0.047). Unfavorable outcome (modified Rankin scale score greater than 2) was not significantly associated with aneurysm shape (P= 0.998) and IOR (P= 0.260). Our results demonstrate that IRA shape is an independent risk factor for IOR. In the analyzed patient cohort, aneurysm shape and IOR had no significant impact on patient prognosis.

Comparison between frontolateral approach and pterional approach in the surgical treatment of paraclinoid aneurysms

ObjectiveTo compare the pterional and frontolateral approach to determine the most effective route for paraclinoid aneurysm surgery. MethodsBetween June 2010 and December 2015, a total of 176 patients with paraclinoid aneurysm underwent surgical clipping, 96 through the pterional and 80 through the frontolateral approach. We analyzed the two groups and compared demographic, radiologic, and clinical variables including age, sex, aneurysm type,intraoperative rupture rates, operative time,anatomical obstacles,outcome and postoperative complications. ResultsThe 2 groups were comparable with respect to baseline characteristics. The mean operation time was also signifcantly shorter in frontolateral group than in the pterion group (204.3 min vs. 264.1 min, p < 0.05). Furthermore, the mean craniotomy area was much smaller in the frontolateral group (1255.4 mm2 vs. 2758.5 mm2, p < 0.05). No patient experienced rebleeding in either group. In the frontolateral group, the exploration allows enough room for intracranial manipulation with maximal protection of the brain and other intracranial structures. ConclusionThe frontolateral approach is a simple, reliable, and efficient procedure. The frontolateral approach could be a good alternative to the classic pterional approach for the treatment of paraclinoid aneurysms.

Endovascular treatment of ruptured tiny (⩽3 mm) intracranial aneurysms in the setting of subarachnoid hemorrhage: A case series of 20 patients and literature review

Successful endovascular coiling of ruptured tiny saccular intracranial aneurysms (⩽3mm) is technically challenging and traditionally has been associated with technical failures, as well as morbidity related to thromboembolic events and high intraoperative rupture rates. This study analyzes the feasibility, technical efficacy, and clinical outcomes of coil embolization of ruptured tiny intracranial aneurysms using current coil and microcatheter technology and techniques. We performed a retrospective review of 20 patients with 20 ruptured tiny aneurysms treated with endovascular coil embolization from 2013 to 2016 at a single high-volume academic tertiary care practice. The mean aneurysm size was 2.4mm (median 2.5mm, 1–3). Complete occlusion was achieved in 12 of 20 patients (60%), the remaining 7 of 20 patients (35%) had a small neck remnant, and there was 1 failure (5%) converted to microsurgical clipping. Two patients had a failed attempted surgical clip reconstruction and were subsequently coiled. There was 1 intraprocedural rupture (5%) and 1 severe parent artery vasospasm (5%) during coiling. At discharge, 60% of patients were living independently. At follow-up three patients were deceased. Mean angiographic follow-up was 139days (SD 120). There were no aneurysm recurrences among occluded patients and there were no retreatments among those with neck remnants. Coiling of ruptured aneurysms ⩽3mm is feasible with high occlusion rates and low complication rates. The availability of softer coils with flexible detachment zones has led to safe and effective endovascular treatment of tiny ruptured aneurysms.

Blister Aneurysms of the Internal Carotid Artery: Microsurgical Results and Management Strategy.

Blister aneurysms of the supraclinoid internal carotid artery (ICA) are challenging lesions with high intraoperative rupture rates and significant morbidity. An optimal treatment strategy for these aneurysms has not been established. To analyze treatment strategy, operative techniques, and outcomes in a consecutive 17-year series of ICA blister aneurysms treated microsurgically. Seventeen patients underwent blister aneurysm treatment with direct clipping, bypass and trapping, or clip-reinforced wrapping Twelve aneurysms (71%) were treated with direct surgical clipping. Three patients required bypass: 1 superficial temporal artery to middle cerebral artery bypass, 1 external carotid artery to middle cerebral artery bypass, and 1 ICA to middle cerebral artery bypass. One patient was treated with clip-reinforced wrapping. Initial treatment strategy was enacted 71% of the time. Intraoperative rupture occurred in 7 patients (41%), doubling the rate of a poor outcome (57% vs 30% for patients with and without intraoperative rupture, respectively). Severe vasospasm developed in 9 of 16 patients (56%). Twelve patients (65%) were improved or unchanged after treatment, and 10 patients (59%) had good outcomes (modified Rankin Scale scores of 1 or 2). ICA blister aneurysms can be cautiously explored and treated with direct clipping as the first-line technique in the majority of cases. Complete trapping of the parent artery with temporary clips and placing permanent clip blades along normal arterial walls enables clipping that avoids intraoperative aneurysm rupture. Trapping/bypass is used as the second-line treatment, maintaining a low threshold for bypass with extensive or friable pathology of the carotid wall and in patients with incomplete circles of Willis.

Procedure-related Complication Rate for the Endovascular Treatment of Aneurysmal Subarachnoid Hemorrhage under Local Anesthesia.

ObjectiveTo report the procedure related complication rate of endovascular treatments (EVTs) performed on patients with aneurysmal subarachnoid hemorrhage (aSAH) under local anesthesia (LA).Materials and MethodsThis study enrolled 186 patients who underwent EVT for ruptured aneurysm under LA from January 2009 to December 2013. Procedure-related complications rate and factors associated with it were analyzed depending on the patients' factors, aneurysm factors and physician factors.ResultsAmong the 186 patients who underwent EVT under LA, the respective rates of thromboembolic complication (TEC) and intraoperative rupture (IOR) were 12.8% (23 cases) and 12.9% (24 cases), respectively. Aneurysm size (≥ 7 mm) was the only risk factor for TEC (p = 0.048).ConclusionCompared to previous result with under general anesthesia (GA), the rate of TEC was similar in patients treated under LA, but the IOR rate was significantly higher. The main reason for increasing IOR is considered as the unexpected patients' motion and in accordance with the unexpected movement of the microinstruments. Therefore, another methods to stabilize the patients or switching from LA to GA may be necessary when performing EVT, to reduce complications.

Analysis of superiorly projecting anterior communicating artery aneurysms: anatomy, techniques, and outcome. A proposed classification system.

Superiorly projecting (SP) anterior communicating artery (AComA) aneurysms are typically described as a homogenous group. Clinically and microsurgically, these aneurysms vary in multiple important characteristics. We propose a microsurgical classification system for these complex aneurysms and review its implications regarding presentation, microsurgical techniques, and outcome. This retrospective analysis reviews patients undergoing clipping of SP AComA aneurysms (2005-2013). The classification system is based on the virtual plane created by the A2 segments and its relationship to the aneurysm. Aneurysm type was assessed by intraoperative images and videos. Type 1 is defined by bisection of the dome by the virtual plane. Type 2 is defined by dome projection posterior to this plane. Sagittal rotation of the plane defines type 3. We analyzed clinical presentation, morphology, angiographic characteristics, operative technique, and outcome relative to the classification types. There were 44 SP AComA aneurysms. 3D angiographic images predicted classification type in 83%. Type 1 presented more often with SAH (95.5%, p = 0.0046). There was no statistically significant difference between the types regarding patient demographics or aneurysm characteristics. In type 2, fenestrated clips were used frequently (87.5% p= 0.0016), and there was higher rate of intraoperative rupture (37.5%). Although there was no statistically significant difference between the types in respect to HH grade upon presentation, patients with type 2 aneurysms experienced higher rates of poor GOS (50%). The proposed classification system for SP AComA aneurysms has implications regarding surgical planning, micro-dissection, clipping, and outcome. Type 2 aneurysms carry significant surgical risk.