
Neurosurgery 72:143–150, 2013
It is not known what effect pregnancy or delivery has on the risk of rupture of an intracranial aneurysm, and, consequently, the optimal management of unruptured aneurysms in pregnancy is unclear.
OBJECTIVE: To study the effect of pregnancy and delivery on the risk of rupture of intracranial aneurysms and to delineate trends in neurosurgical and obstetric management of pregnant women with intracranial aneurysms.
METHODS: The Nationwide Inpatient Sample data were analyzed for years 1988 to 2009 to estimate the risk of aneurysm rupture during pregnancies and deliveries. We calculated the risk by dividing the observed number of patients with ruptured aneurysm during pregnancy and delivery by the expected number based on the incidence among women of pregnancy age.
RESULTS: There were 714 and 172 hospitalizations involving ruptured aneurysms with pregnancy and delivery, respectively. Assuming 1.8% prevalence of unruptured aneurysms among all women of pregnancy age, we estimated that 48 873 women hospitalized for pregnancy and 312 128 women hospitalized for delivery had unruptured aneurysms. The risks of rupture during pregnancy and deliveries were 1.4% (95% confidence interval [CI] = [1.35, 1.57]) and 0.05% (95% CI = [0.0468, 0.0634]), respectively. Of 218 deliveries performed with unruptured aneurysm, 153 were cesarean deliveries (70.18%, 95% CI = [64.06, 76.30%]), suggesting that the rate of cesarean deliveries in patients with unruptured aneurysms is significantly higher than in the general population (P < .001).
CONCLUSION: We were not able to find an increased association between pregnancy or delivery and the risk of rupture of cerebral aneurysms. The significantly higher rate of cesarean deliveries performed in patients with unruptured aneurysms may not be necessary.

Neurosurgery 71:994–1002, 2012
Recognizing an aneurysmal basal rupture using angiographic evaluation is crucial for optimal treatment.
OBJECTIVE: To evaluate the incidence of a small basal outpouching (the most common angiographic configuration suggesting a basal rupture), the incidence of a ruptured basal outpouching, and the results of surgical and endovascular treatments.
METHODS: The occurrence of small basal outpouchings was determined in the initial angiographic examinations of 471 patients with a ruptured aneurysm. Information was also obtained from patient charts, surgical and interventional reports, operative video records, and reviews of radiological investigations.
RESULTS: A small basal outpouching was identified in 41 (8.7%) of the 471 ruptured aneurysms. In the surgical series (n = 286), a basal rupture was identified in 8 (30.8%) of the 26 cases of a basal outpouching and successfully treated by aneurysm clip placement. In the endovascular series (n = 185), intraprocedural aneurysm rebleeding developed in 5 of the 15 patients (33.3%) with a basal outpouching, which was most commonly observed with anterior communicating artery aneurysms.
CONCLUSION: The current surgical series included a 9% incidence of ruptured intracranial aneurysms with a small basal outpouching, and a 31% incidence of these basal outpouchings being identified as the rupture point. The results also suggested that endovascular coiling of a basal outpouching carries a high risk of intraprocedural aneurysm rebleeding, whereas surgical clipping is safer and provides more protection against rebleeding of aneurysms with a basal rupture.

J Neurosurg 117:20–25, 2012
In this paper, the authors’ goals were to clarify the characteristics of growing unruptured cerebral aneurysms detected by serial MR angiography and to establish the recommended follow-up interval.
Methods. A total of 1002 patients with 1325 unruptured cerebral aneurysms were retrospectively identified. These patients had undergone follow-up evaluation at least twice. Aneurysm growth was defined as an increase in maximum aneurysm diameter by 1.5 times or the appearance of a bleb.
Results. Aneurysm growth was observed in 18 patients during the period of this study (1.8%/person-year). The annual rupture risk after growth was 18.5%/person-year. The proportion of females among patients with growing aneurysms was significantly larger than those without growing aneurysms (p = 0.0281). The aneurysm wall was reddish, thin, and fragile on intraoperative findings. Frequent follow-up examination is recommended to detect aneurysm growth before rupture.
Conclusions. Despite the relatively short period, the annual rupture risk of growing unruptured cerebral aneurysms detected by MR angiography was not as low as previously reported. Surgical or endovascular treatment can be considered if aneurysm growth is detected during the follow-up period.

Neuroradiology (2012) 54:597–606. DOI 10.1007/s00234-011-0945-0
Endovascular treatment of cerebral aneurysms includes follow-up imaging to identify aneurysms that may need retreatment. The aim of this study was to determine predictors of incomplete aneurysm occlusion at 1 year after endovascular coiling for ruptured cerebral aneurysms.
Methods In 129 patients of the Prospective Registry of Subarachnoid Aneurysms Treatment cohort, ruptured aneurysms were coiled within 14 days of onset and both initial post-coiling and 1-year follow-up digital subtraction angiography or magnetic resonance angiography were obtained. Factors predicting 1-year incomplete aneurysm occlusion (retreatment within 1-year or residual aneurysms at 1 year) were determined using multivariate logistic regression analyses.
Results One-year incomplete aneurysm occlusion was identified in 59 patients, including ten patients who were retreated within 1-year post-coiling. Dome size ≥7.5 mm (P=0.007, odds ratio (OR)=5.00, 95% confidence interval (CI)=1.55– 16.15), pre-treatment aneurysm re-rupture (P=0.023, OR= 3.50, 95% CI=1.19–10.31), non-small size/small neck aneurysm (dome size, ≥10 mm or neck size, ≥4 mm; P= 0.022, OR=3.26, 95% CI=1.19–8.96), and residual aneurysms on immediate post-coiling angiograms (P=0.017, OR= 1.43, 95% CI=1.07–1.93) significantly predicted incomplete aneurysm occlusion at 1-year post-coiling.
Conclusions In addition to the characteristics of aneurysm and initially incomplete aneurysm occlusion, this study showed pre-treatment aneurysm re-rupture to be a predictor that favors closer imaging follow-ups for coiled aneurysms.
Neurosurgery 70:537–554, 2012 DOI: 10.1227/NEU.0b013e3182350da5
Coil instability possibly translating into higher delayed rebleeding rates remains a concern in the endovascular management of cerebral aneurysms.
OBJECTIVE: To report on 127 patients with endovascular aneurysmal remnants who underwent re-treatment over an 18 year period.
METHODS: Patients presenting with aneurysm residuals .20% of the original lesion, unstable neck remnants, aneurysmal regrowth, or new aneurysmal daughter sacs were treated by an individualized approach, using both endovascular and surgical techniques.
RESULTS: Seventy-five aneurysmal remnants (59.1%) were treated by further re-embolization. Standard coil embolization was used in 65 cases, stent-protected coiling in 9 cases, and balloon remodeled coiling in 1 case, respectively. Fifty-two (40.9%) aneurysmal remnants were treated surgically. Standard microsurgical clipping was used in 44 patients, parent artery occlusion or trapping under bypass protection in 5 cases, deliberate clipping of the basilar artery trunk in 2 cases, and aneurysm wrapping in one case, respectively. Mechanisms of aneurysm recurrence were coil compaction in 93 cases and regrowth in 34 cases. A single reembolization was sufficient to occlude 78.7% of recurrences from coil compaction, but only 14.3% of recurrences from aneurysm regrowth.
CONCLUSION: The individualized approach resulted in complete occlusion of 114 aneurysms (89.7%), with neck remnants and residual aneurysms detectable in 11 (8.7%) and 2 (1.6%) cases, respectively. Treatment morbidity was 11.9%, without significant differences between surgical (15.6%) and endovascular (9.3%) patients (P = .09). Recurrences from coil compaction were safely treated by re-embolization, whereas recurrences from aneurysmal regrowth may best be managed surgically when technically feasible.
Neurosurgery 68[ONS Suppl 2]:ons300–ons309, 2011 DOI: 10.1227/NEU.0b013e3182124810
Neurovascular surgeons have been trying to find a solution to the problem of surgical invasiveness by applying minimally invasive keyhole approaches.
OBJECTIVE: To evaluate the feasibility and surgical outcomes of a superciliary keyhole approach for unruptured intracranial aneurysms (UIAs) as an alternative to a pterional approach.
METHODS: The authors report on a consecutive series of patients who underwent a superciliary approach for clipping UIAs smaller than 15 mm arising at the supraclinoid internal carotid artery (ICA), A1 segment, anterior communicating artery (ACoA), and M1 segment including the middle cerebral artery (MCA) bifurcation. The data were compared with a historical control group (n = 90) who underwent a pterional approach for UIAs.
RESULTS: A total of 120 aneurysms were successfully clipped in 102 patients with a mean age of 58 years. There was no direct mortality related to the surgery, and only 1 (1.0%) patient developed significant morbidity adversely affecting the Glasgow Outcome Scale score. The superciliary approach demonstrated statistically significant advantages over the pterional approach, including a shorter operative duration (mean, 120 min), no intraoperative blood transfusion, and extremely rare postoperative epidural hemorrhages. In addition, temporalis atrophy was rare and palsy of the frontalis persisting more than 6 months only occurred in 6 patients (5.9%) and was resolved within 2 years. The overall cosmetic outcome was excellent.
CONCLUSION: A superciliary approach can be a reasonable alternative to a pterional approach for small (,15 mm) UIAs arising at the supraclinoid ICA, A1, ACoA, and M1 segment including the MCA bifurcation.
J Neurosurg 113:774–780, 2010. DOI: 10.3171/2010.2.JNS09376
The purpose of this study was to identify predictors of shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage (SAH).
Methods. The authors evaluated the incidence of shunt-dependent hydrocephalus in a consecutive cohort of 580 patients with SAH who were admitted to the Neurological Intensive Care Unit of Columbia University Medical Center between July 1996 and September 2002. Patient demographics, 24-hour admission variables, initial CT scan characteristics, daily transcranial Doppler variables, and development of in-hospital complications were analyzed. Odds ratios and 95% CIs for candidate predictors were calculated using multivariate nominal logistic regression.
Results. Admission glucose of at least 126 mg/dl (adjusted OR 1.6; 95% CI 1.0–2.6), admission brain CT scan with a bicaudate index of at least 0.20 (adjusted OR 1.43; 95% CI 1.0–2.0), Fisher Grade 4 (adjusted OR 2.71; 95% CI 1.2–5.7), fourth ventricle hemorrhage (adjusted OR 1.78; 95% CI 1.1–2.7), and development of nosocomial meningitis (adjusted OR 2.2; 95% CI 1.4–3.7) were independently associated with shunt dependency.
Conclusions. These data suggest that permanent CSF diversion after aneurysmal SAH may be independently predicted by hyperglycemia at admission, findings on the admission CT scan (Fisher Grade 4, fourth ventricle intraventricular hemorrhage, and bicaudate index ≥ 0.20), and development of nosocomial meningitis. Future research is needed to assess if tight glycemic control, reduction of fourth ventricle clot burden, and prevention of nosocomial meningitis may reduce the need for permanent CSF diversion after aneurysmal SAH.
Neurosurgery 67:844-854, 2010 DOI: 10.1227/01.NEU.0000374684.10920.A2
Multidetector computerized tomography angiography (MDCTA) is now a widely accepted technique for the management of intracranial aneurysms.
OBJECTIVE: To evaluate its accuracy for the postoperative assessment of clipped intracranial aneurysms.
METHODS:We analyzed a consecutive series of 31 patients that underwent direct surgical clipping procedures of 38 aneurysms. A 64 slice MDCT scanner (Aquilion 64, Toshiba) was used and results were compared with digital subtraction angiographies (DSA). Two independent neuroradiologists analyzed the following data: examination quality, artifacts, aneurysm remnant, and patency of collateral branches. Interobserver agreement, sensitivity, and specificity were calculated.
RESULTS: Seventy-nine percent of the aneurysms were located in the anterior circulation. Significant artifacts were found with multiple and cobalt-alloy clips. According to DSA, remnants >2 mm were found in 21% of the cases, and 2 patients had one collateral branch occluded. Sensitivity and specificity of 64-MDCTA for the detection of aneurysm remnants were 50% and 100%, respectively. Sensitivity and specificity of 64-MDCTA for the detection of a significant remnant (>2 mm) and the detection of the occlusion of a collateral branch were, respectively, 67% and 100% and 50% and 100%. No relationship was found with the location, type, shape, size, or number of clips, but missed remnants tended to be larger with cobalt-alloy clips.
CONCLUSIONS: 64-MDCTA is a valuable technique to assess the presence of a significant postoperative remnant in single titanium clip application cases and might be useful for longterm follow-up. DSA remains the most accurate postoperative radiological examination.
Neurosurgery 00:000-000, 2010 DOI: 10.1227/01.NEU.0000374684.10920.A2
Multidetector computerized tomography angiography (MDCTA) is now a widely accepted technique for the management of intracranial aneurysms.
OBJECTIVE: To evaluate its accuracy for the postoperative assessment of clipped intracranial aneurysms.
METHODS:We analyzed a consecutive series of 31 patients that underwent direct surgical clipping procedures of 38 aneurysms. A 64 slice MDCT scanner (Aquilion 64, Toshiba) was used and results were compared with digital subtraction angiographies (DSA). Two independent neuroradiologists analyzed the following data: examination quality, artifacts, aneurysm remnant, and patency of collateral branches. Interobserver agreement, sensitivity, and specificity were calculated.
RESULTS: Seventy-nine percent of the aneurysms were located in the anterior circulation. Significant artifacts were found with multiple and cobalt-alloy clips. According to DSA, remnants >2 mm were found in 21% of the cases, and 2 patients had one collateral branch occluded. Sensitivity and specificity of 64-MDCTA for the detection of aneurysm remnants were 50% and 100%, respectively. Sensitivity and specificity of 64-MDCTA for the detection of a significant remnant (>2 mm) and the detection of the occlusion of a collateral branch were, respectively, 67% and 100% and 50% and 100%. No relationship was found with the location, type, shape, size, or number of clips, but missed remnants tended to be larger with cobalt-alloy clips.
CONCLUSIONS: 64-MDCTA is a valuable technique to assess the presence of a significant postoperative remnant in single titanium clip application cases and might be useful for longterm follow-up. DSA remains the most accurate postoperative radiological examination.
J Neurosurg 112:1200–1207, 2010. DOI: 10.3171/2009.10.JNS08754
The aim of the study was to assess postprocedural neurological deterioration and outcome in patients older than 70 years of age in whom treatment was managed in an interdisciplinary context.
Methods. This prospective longitudinal study included all patients 70 years of age or older treated for ruptured cerebral aneurysm over 10 years (June 1997–June 2007). The population was composed of 64 patients. The neurovascular interdisciplinary team jointly discussed the early obliteration procedure for each aneurysm. Neurological deterioration during the postprocedural 2 months and outcome at 6 months were assessed during consultation according to the modified Rankin Scale (mRS) as follows: favorable (mRS score ≤ 2) and unfavorable (mRS score > 2).
Results. Aneurysm sac obliteration was performed by microvascular clipping in 34 patients (53.1%) and by endovascular coiling in 30 (46.9%). Postprocedural neurological deterioration occurred in 30 patients (46.9%), related to ischemia in 19 (29.7%), rebleeding in 1 (1.6%), and hydrocephalus in 10 (15.6%). At 6 months, the outcome was favorable in 39 patients (60.9%). By multivariate regression logistic analysis, the independent factors associated with unfavorable outcome were age exceeding 75 years (p = 0.005), poor initial grade (p < 0.0001), and the occurrence of ischemia (p < 0.0001).
Conclusions. The baseline characteristics of SAH in the elderly were only slightly different from those in younger patients. In the elderly, the interdisciplinary approach may be considered useful to decrease the ischemic consequences.
Acta Neurochir (2010) 152:793–802 DOI 10.1007/s00701-009-0465-4
The aim of our study was to evaluate the diagnostic efficacy of multislice computed tomographic angiography (MSCTA) regarding exclusion quality after aneurysm clipping.
Methods. Sixty patients (74 aneurysms) underwent microsurgical exclusion using titanium clips. The presence of aneurysm remnants on MSCTA was compared by a neuroradiologist to 2D digital subtraction angiography (DSA), which was considered as a reference examination. The contribution of 3D DSA was assessed in a subpopulation of 29 patients (35 aneurysms).
Results. With 2D DSA, six aneurysm remnants (8%) were diagnosed, and only five (7%) by MSCTA. The specificity and sensitivity were 98.5 and 83%, respectively. MSCTA failed to demonstrate one large remnant (>2 mm) because of clip artifacts (six clips). With 3D DSA six supplementary remnants were diagnosed. Two were large remnants blinded by vessel overlaps and clip artifacts. Four were small “dogeared” remnants (≤2 mm). No additional treatment was required for small remnants.
Conclusion. In the postoperative period, MSCTA was considered a useful tool to evaluate the large remnants as well as a non-invasive ulterior examination for suspected bifurcation. Nevertheless, 3D DSA is still required for an accurate evaluation of aneurysms treated by more than three clips.
Neurosurg Rev (2010) 33:205–216. DOI 10.1007/s10143-009-0234-0
Non-saccular aneurysms (NSAs) of the internal carotid artery trunk include blood blister-like aneurysms (BBAs) and dissecting aneurysms (DAs), which are susceptible to disastrous intra- and postoperative bleeding. This study was conducted to clarify the clinical features of NSAs and the results of early bypass and trapping. Nineteen ruptured NSAs were identified in 937 patients with subarachnoid hemorrhage (SAH). The principal treatment was to trap the aneurysm following bypass surgery as soon as possible after SAH onset. Angiography revealed nine BBAs and ten DAs. Eight patients (four BBA and four DA) were treated in the chronic stage because of delayed arrival (n=3) or lack of aneurysm on initial angiography (n=3), or other reasons (n=2). The remaining 11 patients underwent early surgery using trapping after bypass, except for one BBA-type (clipped). During surgery, corresponding intraoperative findings were confirmed for each aneurysm type. There were six preoperative reruptures; five were determinant of patient outcome. In 14 patients without preoperative rerupture influencing outcome, 11 patients were independent at discharge and three patients dependent due to surgical complication. There was one case of minor intraoperative bleeding; no postoperative rerupture occurred. There was no delayed vasospasm-related deficit, although temporary symptomatic spasm occurred in three patients. Early bypass and trapping appeared to be an acceptable treatment strategy for these NSAs eliminating intra- and postoperative bleeding and not increasing a chance of delayed vasospasm.
Neurosurgery 65:719–726, 2009 DOI: 10.1227/01.NEU.0000354350.88899.07
OBJECTIVE: With improvements in endovascular techniques, fewer aneurysms are treated by surgical clipping, and those aneurysms targeted for open surgery are often complex and difficult to treat. We devised a hollow, 3-dimensional (3D) model of individual cerebral aneurysms for preoperative simulation and surgical training. The methods and initial experience with this model system are presented.
METHODS:The 3D hollow aneurysm models of 3 retrospective and 8 prospective cases were made with a prototyping technique according to data from 3D computed tomographic angiograms of each patient. Commercially available titanium clips used in our routine surgery were applied, and the internal lumen was observed with an endoscope to confirm the patency of parent vessels. The actual surgery was performed later.
RESULTS: In the 8 prospective cases, the clips were applied during surgery in the same direction and configuration as in the preoperative simulation. Fine adjustments were necessary in each case, and 2 patients needed additional clips to occlude the atherosclerotic aneurysmal wall. With these 3D models, it was easy for neurosurgical trainees to grasp the vascular configuration and the concept of neck occlusion. Practicing surgery with these models also improved their handling of the instruments used during
aneurysm surgery, such as clips and appliers.
CONCLUSION: Using the hollow 3D models to simulate clipping preoperatively, we could treat the aneurysms confidently during live surgery. These models allow easy and concrete recognition of the 3D configuration of aneurysms and parent vessels.