Predictors of 30-day perioperative morbidity and mortality of unruptured intracranial aneurysm surgery

Microsurgical clipping of unruptured intracranial aneurysms: Clinical and radiological outcomes

BACKGROUND AND OBJECTIVES

The prevalence of unruptured intracranial aneurysms is 1-3%. The annual rupture rate increases in patients with multiple aneurysms that presented a previous hemorrhage from another aneurysm.

OBJECTIVES

To evaluate outcomes of clipping unruptured aneurysms, comparing patients with single or multiple aneurysms clipped, describe the complications related to surgery and to identify risk factors predicting an unfavorable outcome.

MATERIALS AND METHODS

Retrospective study including patients who underwent clipping of unruptured aneurysms between 2020-2023 at our center. Occlusion rate, complications, and functional outcome were analyzed. Risk factors for poor prognosis are identified using univariate model.

RESULTS

82 patients with 114 aneurysms were treated with microsurgery. Multiple aneurysms were clipped in 22 patients. A mini-open approach was used in 86,5% of cases. Complete occlusion in angio3D was found in 78.6% of clipped aneurysms. Complication rate was 12.2%, including asymptomatic cases. Mortality was 0%. The probability of 1 point mRS worsening was 7.3% and 2 or more points was 1.2%, with a good functional outcome in 98.9%. Clipping multiple aneurysms, miniopen approaches, or surgery in patients with previous subarachnoid hemorrhage did not increase the risk of complications. Posterior circulation aneurysms surgery increased the risk of ischemia.

CONCLUSIONS

The management for unruptured intracranial aneurysms should be multimodal and based on clinical and radiological outcomes. Microsurgery is a valid and safe technique, with 0% mortality and bleeding rates and 1,2% rate of severe morbidity in our series.

Feasibility, Safety, and Efficacy of Endovascular vs. Surgical Treatment of Unruptured Multi-Sac Intracranial Aneurysms in a Single-Center Retrospective Series

PURPOSE

Multi-sac aneurysms (MSAs) are not uncommon, but studies on their management are scarce. This study aims to evaluate and compare the feasibility, safety, and efficacy of MSAs treated with either clipping or coiling after interdisciplinary case discussion at our center.

MATERIALS AND METHODS

We retrospectively analyzed MSAs treated by microsurgical clipping, coiling, or stent-assisted coiling (SAC). Treatment modalities, complications, angiographic results, and clinical outcomes were evaluated. Major neurological events were defined as a safety endpoint and complete occlusion as an efficacy endpoint.

RESULTS

Ninety patients (mean age, 53.2±11.0 years; 73 [81.1%] females) with MSAs met our inclusion criteria (clipping, 50; coiling, 19; SAC, 21). Most aneurysms were located in the middle cerebral artery (48.9%). All clipping procedures were technically successful, but endovascular treatment failed in 1 coiling case, and a switch from coiling to SAC was required in 2 cases. The major event rates were 4.0% after clipping (1 major stroke and 1 intracranial hemorrhage) and 0% after endovascular therapy (P=0.667). At mid-term angiographic follow-up (mean 12.0±8.9 months), all 37 followed clipped aneurysms were completely occluded, compared to 8/17 (41.7%) after coiling and 11/15 (73.3%) after SAC (P<0.001). Coiling was significantly associated with incomplete occlusion in the adjusted analysis (odds ratio, 11.7; 95% confidence interval, 2.7-52.6; P=0.001).

CONCLUSION

Both endovascular and surgical treatment were feasible and safe for MSAs. As coiling was associated with comparatively high recanalization rates, endovascular treatment may be preferred with stent support.

Global Outcomes for Microsurgical Clipping of Unruptured Intracranial Aneurysms: A Benchmark Analysis of 2245 Cases

BACKGROUND AND OBJECTIVES

Benchmarks represent the best possible outcome and help to improve outcomes for surgical procedures. However, global thresholds mirroring an optimal and reachable outcome for microsurgical clipping of unruptured intracranial aneurysms (UIA) are not available. This study aimed to define standardized outcome benchmarks in patients who underwent clipping of UIA.

METHODS

A total of 2245 microsurgically treated UIA from 15 centers were analyzed. Patients were categorized into low- ("benchmark") and high-risk ("nonbenchmark") patients based on known factors affecting outcome. The benchmark was defined as the 75th percentile of all centers' median scores for a given outcome. Benchmark outcomes included intraoperative (eg, duration of surgery, blood transfusion), postoperative (eg, reoperation, neurological status), and aneurysm-related factors (eg, aneurysm occlusion). Benchmark cutoffs for aneurysms of the anterior communicating/anterior cerebral artery, middle cerebral artery, and posterior communicating artery were determined separately.

RESULTS

Of the 2245 cases, 852 (37.9%) patients formed the benchmark cohort. Most operations were performed for middle cerebral artery aneurysms (53.6%), followed by anterior communicating and anterior cerebral artery aneurysms (25.2%). Based on the results of the benchmark cohort, the following benchmark cutoffs were established: favorable neurological outcome (modified Rankin scale ≤2) ≥95.9%, postoperative complication rate ≤20.7%, length of postoperative stay ≤7.7 days, asymptomatic stroke ≤3.6%, surgical site infection ≤2.7%, cerebral vasospasm ≤2.5%, new motor deficit ≤5.9%, aneurysm closure rate ≥97.1%, and at 1-year follow-up: aneurysm closure rate ≥98.0%. At 24 months, benchmark patients had a better score on the modified Rankin scale than nonbenchmark patients.

CONCLUSION

This study presents internationally applicable benchmarks for clinically relevant outcomes after microsurgical clipping of UIA. These benchmark cutoffs can serve as reference values for other centers, patient registries, and for comparing the benefit of other interventions or novel surgical techniques.

Microsurgical Clipping of Unruptured Anterior Circulation Aneurysms-A Global Multicenter Investigation of Perioperative Outcomes

BACKGROUND AND OBJECTIVES

Microsurgical aneurysm repair by clipping continues to be highly important despite increasing endovascular treatment options, especially because of inferior occlusion rates. This study aimed to present current global microsurgical treatment practices and to identify risk factors for complications and neurological deterioration after clipping of unruptured anterior circulation aneurysms.

METHODS

Fifteen centers from 4 continents participated in this retrospective cohort study. Consecutive patients who underwent elective microsurgical clipping of untreated unruptured intracranial aneurysm between January 2016 and December 2020 were included. Posterior circulation aneurysms were excluded. Outcome parameters were postsurgical complications and neurological deterioration (defined as decline on the modified Rankin Scale) at discharge and during follow-up. Multivariate regression analyses were performed adjusting for all described patient characteristics.

RESULTS

Among a total of 2192 patients with anterior circulation aneurysm, complete occlusion of the treated aneurysm was achieved in 2089 (95.3%) patients at discharge. The occlusion rate remained stable (94.7%) during follow-up. Regression analysis identified hypertension (P < .02), aneurysm diameter (P < .001), neck diameter (P < .05), calcification (P < .01), and morphology (P = .002) as preexisting risk factors for postsurgical complications and neurological deterioration at discharge. Furthermore, intraoperative aneurysm rupture (odds ratio 2.863 [CI 1.606-5.104]; P < .01) and simultaneous clipping of more than 1 aneurysm (odds ratio 1.738 [CI 1.186-2.545]; P < .01) were shown to be associated with an increased risk of postsurgical complications. Yet, none of the surgical-related parameters had an impact on neurological deterioration. Analyzing volume-outcome relationship revealed comparable complication rates (P = .61) among all 15 participating centers.

CONCLUSION

Our international, multicenter analysis presents current microsurgical treatment practices in patients with anterior circulation aneurysms and identifies preexisting and surgery-related risk factors for postoperative complications and neurological deterioration. These findings may assist in decision-making for the optimal therapeutic regimen of unruptured anterior circulation aneurysms.

Mortality After Microsurgical Treatment of Unruptured Intracranial Aneurysms in the Modern Era

BACKGROUND

The incidence of mortality after treatment of unruptured intracranial aneurysms (UIAs) has been described historically. However, many advances in microsurgical treatment have since emerged, and most available data are outdated. We analyzed the incidence of mortality after microsurgical treatment of patients with UIAs treated in the past decade.

METHODS

The medical records of all patients with UIAs who underwent elective treatment at our large quaternary center from January 1, 2014, to December 31, 2020, were reviewed retrospectively. We analyzed mortality at discharge and 1-year follow-up as the primary outcome using univariate to multivariable progression with P < 0.20 inclusion.

RESULTS

During the 7-year study period, 488 patients (mean [SD] age = 58 [12] years) had UIAs treated microsurgically. Of these patients, 61 (12.5%) had a prior subarachnoid hemorrhage. One patient (0.2%) with a dolichoectatic vertebrobasilar aneurysm died while hospitalized, and 7 other patients (8 total; 1.6%) were determined to have died at 1-year follow-up (1 trauma, 2 myocardial infarction, 2 cerebrovascular accident, 1 pulmonary embolism, and 1 subdural hematoma complicated by abscess). On univariate analysis, significant risk factors for mortality at follow-up included diabetes mellitus, preoperative anticoagulant or antiplatelet use, aneurysm calcification, nonsaccular aneurysm, and higher American Society of Anesthesiologists grades (all P < 0.03). On multivariable logistic regression analysis, only nonsaccular aneurysms and higher American Society of Anesthesiologists grades were predictors of mortality.

CONCLUSIONS

A low mortality rate is associated with recent microsurgical treatment of UIAs. However, nonsaccular aneurysms and higher American Society of Anesthesiologists grades appear to be predictors of mortality.

Benchmarking short-term postoperative mortality across neurosurgery units: is hospital administrative data good enough for risk-adjustment?

BACKGROUND

Surgical mortality indicators should be risk-adjusted when evaluating the performance of organisations. This study evaluated the performance of risk-adjustment models that used English hospital administrative data for 30-day mortality after neurosurgery.

METHODS

This retrospective cohort study used Hospital Episode Statistics (HES) data from 1 April 2013 to 31 March 2018. Organisational-level 30-day mortality was calculated for selected subspecialties (neuro-oncology, neurovascular and trauma neurosurgery) and the overall cohort. Risk adjustment models were developed using multivariable logistic regression and incorporated various patient variables: age, sex, admission method, social deprivation, comorbidity and frailty indices. Performance was assessed in terms of discrimination and calibration.

RESULTS

The cohort included 49,044 patients. Overall, 30-day mortality rate was 4.9%, with unadjusted organisational rates ranging from 3.2 to 9.3%. The variables in the best performing models varied for the subspecialties; for trauma neurosurgery, a model that included deprivation and frailty had the best calibration, while for neuro-oncology a model with these variables plus comorbidity performed best. For neurovascular surgery, a simple model of age, sex and admission method performed best. Levels of discrimination varied for the subspecialties (range: 0.583 for trauma and 0.740 for neurovascular). The models were generally well calibrated. Application of the models to the organisation figures produced an average (median) absolute change in mortality of 0.33% (interquartile range (IQR) 0.15-0.72) for the overall cohort model. Median changes for the subspecialty models were 0.29% (neuro-oncology, IQR 0.15-0.42), 0.40% (neurovascular, IQR 0.24-0.78) and 0.49% (trauma neurosurgery, IQR 0.23-1.68).

CONCLUSIONS

Reasonable risk-adjustment models for 30-day mortality after neurosurgery procedures were possible using variables from HES, although the models for trauma neurosurgery performed less well. Including a measure of frailty often improved model performance.

Nomogram model for predicting oculomotor nerve palsy in patients with intracranial aneurysm

AIM

To explore the risk factors of oculomotor nerve palsy (ONP) in patients with intracranial aneurysm (IA) and develop a nomogram model for predicting ONP of IA patients.

METHODS

A total of 329 IA patients were included. Logistic regression analysis was applied to identify independent factors, which were then integrated into the nomogram model. The performance of the nomogram model was evaluated by calibration curve, receiver operating curve (ROC), and decision curve analysis.

RESULTS

Univariate and multivariate logistic regression analysis indicated posterior communicating artery (PCoA) aneurysm [hazard ratio (HR)=17.13, P<0.001] and aneurysm diameter (HR=1.31, P<0.001) were independent risk factors of ONP in IA patients. Based on the results of logistic regression analysis, a nomogram model for predicting the ONP in IA patients was constructed. The calibration curve indicated the nomogram had a good agreement between the predictions and observations. The nomogram showed a high predictive accuracy and discriminative ability with an area under the curve (AUC) of 0.863. The decision curve analysis showed that the nomogram was powerful in the clinical decision. PCoA aneurysm (HR=3.38, P=0.015) was identified to be the only independent risk factor for ONP severity.

CONCLUSION

PCoA aneurysm and aneurysm diameter are independent risk factors of ONP in IA patients. The nomogram established is performed reliably and accurately for predicting ONP. PCoA aneurysm is the only independent risk factor for ONP severity.

Procedural complications in patients undergoing microsurgical treatment of unruptured intracranial aneurysms: a single-center experience with 1923 aneurysms

BACKGROUND

With the growing use of endovascular therapy (EVT) to manage unruptured intracranial aneurysms (IAs), detailed information regarding periprocedural complication rates of microsurgical clipping and EVT becomes increasingly important in determining the optimal treatment for individual cases. We report the complication rates associated with open microsurgery in a large series of unruptured IAs and highlight the importance of maintaining surgical skill in the EVT era.

METHODS

We reviewed all cases of unruptured IAs treated with open microsurgery by a single neurosurgeon between July 1997 and June 2019. We analyzed surgical complications, deaths, and patient-reported outcomes.

RESULTS

A total of 1923 unruptured IAs in 1750 patients (mean age 44 [range: 6-84], 62.0% [1085/1750] female) were treated surgically during the study period. Of the aneurysms treated, 84.9% (1632/1923) were small, 11.1% (213/1923) were large, and 4.1% (78/1923) were giant. Aneurysm locations included the middle cerebral artery (44.2% [850/1923]), internal carotid artery (29.1% [560/1923]), anterior cerebral artery (21.0% [404/1923]), and vertebrobasilar system (5.7% [109/1923]). The overall mortality rate was 0.3% (5/1750). Surgical complications occurred in 7.4% (129/1750) of patients, but only 0.4% (7/1750) experienced permanent disability. The majority of patients were able to return to their preoperative lifestyles with no modifications (95.9% [1678/1750]).

CONCLUSIONS

At a high-volume, multidisciplinary center, open microsurgery in carefully selected patients with unruptured IAs yields favorable clinical outcomes with low complication rates. The improvement of EVT techniques and the ability to refer cases for EVT when a high complication rate with open microsurgery was expected have contributed to an overall decrease in surgical complication rates. These results may serve as a useful point of reference for physicians involved in treatment decision-making for patients with unruptured IAs.

Endovascular management of large and giant intracranial aneurysms: Experience from a tertiary care neurosurgery institute in India

Objective

With the development of endovascular technique and devices, large and giant intracranial aneurysms are increasingly being managed by this less invasive method. Here we discuss our experience on managing such aneurysms via endovascular technique.

Methods

Retrospective data on 42 patients with large and giant intracranial aneurysms managed by endovascular techniques between September 2015 to December 2017 at our neurosurgery institute were included in this analysis.

Results

There were a total 42 patients with 9 giant and 33 large aneurysms in this study. Eight aneurysms were treated by parent vessel occlusion, 22 aneurysms with coils and rest 12 aneurysms were treated with stent assisted coiling. Following the procedure, Raymond class I occlusion was accomplished in 31 (73.8%) patients while class Ⅱ in 9 (21.4%) and class Ⅲ in 2 (4.8%) patients. Overall morbidity and mortality were 9.5% and 14.3% respectively and favorable outcome was seen in 80.9% patients. Significant correlation was observed with clinical outcome and initial neurological status.

Conclusions

The study indicates that endovascular intervention is a safe and effective method in managing large and giant intracranial aneurysms with lesser morbidity and mortality.

Using a Data-Driven Improvement Methodology to Decrease Surgical Site Infections in a Community Neurosurgery Practice: Optimizing Preoperative Screening and Perioperative Antibiotics

OBJECTIVE

We used a data-driven methodology to decrease the departmental surgical site infection rate to a goal of 1%.

METHODS

A prospective interventional study with historical controls comparing preimplementation/intervention (unknown methicillin-sensitive Staphylococcus aureus [MSSA]/methicillin-resistant Staphylococcus aureus [MRSA] status and standard weight and drug allergy-based preoperative antibiotics) with postimplementation/intervention (optimized preoperative chlorhexidine showers, MSSA/MRSA screening, MSSA/MRSA decolonization, and optimized preoperative antibiotic order set implementation). The American College of Surgeons National Surgical Quality Improvement Program was used for case surveillance. The primary outcome was the presence of a surgical site infection with a secondary outcome of cost(s) of implementation.

RESULTS

A total of 317 National Surgical Quality Improvement Program abstracted neurosurgical cases were analyzed, 163 cases before implementation and 154 cases after implementation. There were no significant differences between the preimplementation and postimplementation cohorts regarding patient demographics and baseline comorbidities, with the exceptions of inpatient and functional status (P < 0.001). The most common procedures were lumbar decompression (31%), lumbar discectomy (27%), and anterior cervical discectomy and fusion (10.4%). After implementation, 30 patients were MSSA positive (20%) and 4 MRSA positive (2.6%). Thirty patients received preoperative intranasal mupirocin decolonization (88%), and 4 patients received adjusted preoperative antibiotics (12%). After protocol implementation, the surgical site infection rate decreased from 6.7% (odds ratio, 2.82) to 0.96% (odds ratio, 0.91). The cost of implementation was $27,179, or $58 per patient.

CONCLUSIONS

The findings highlight the importance of systematically investigating areas of gap in existing clinical practice and quality improvement projects to increase patient safety and enhance the value of care delivered to neurosurgical patients.

Clinical features of ischemic complications after unruptured middle cerebral artery aneurysm clipping: patients and radiologically related factors

Postoperative ischemic complication results in neurological sequelae and longer hospitalization after unruptured middle cerebral artery (MCA) aneurysm clipping surgery. We evaluated the radiological and patient-related factors associated with ischemic complications after unruptured MCA aneurysm clipping surgery. Patient demographics, radiological findings, and intraoperative factors were compared between patients with and without postoperative ischemic complications. The clinical courses and outcomes of postoperative ischemic complications were compared according to the types of ischemic complication. Forty-two out of 2227 patients (1.9%) developed postoperative ischemic complications after MCA aneurysm clipping. Multivariate analysis revealed that diabetes mellitus (DM) was a patient-related factor. Intraarterial (IA) calcification of the distal internal carotid artery (ICA), preoperative M1 stenosis, and M1 aneurysm were radiological factors that increased the risk of postoperative ischemic complications. DM was significantly associated with divisional branch territory infarction (P = 0.04). The time to first presentation of ischemic complication was significantly longer in divisional branch territory infarction than perforator territory infarction (67.8 ± 75.9 h vs. 22 ± 20.7, P = 0.023). Twelve out of 42 patients with ischemic complications (28.6%) had unfavorable outcome (mRS > 3). Perforator territory infarction was significantly associated with an unfavorable outcome (mRS > 3, P = 0.019). IA calcification of the distal ICA, M1 stenosis and aneurysms, and DM were significantly associated with postoperative ischemic complications after unruptured MCA aneurysm clipping. Patients with DM should be closely monitored postoperatively to detect delayed occurrence of divisional branch infarction. Trial registration number: 2019-1002, Date of registration: January 1, 2005, "retrospectively registered".

Adverse events after clipping of unruptured intracranial aneurysms: the NSQIP unruptured aneurysm scale

OBJECTIVE

The complex decision analysis of unruptured intracranial aneurysms entails weighing the benefits of aneurysm repair against operative risk. The goal of the present analysis was to build and validate a predictive scale that identifies patients with the greatest odds of a postsurgical adverse event.

METHODS

Data on patients who underwent surgical clipping of an unruptured aneurysm were extracted from the prospective National Surgical Quality Improvement Program registry (NSQIP; 2007-2014); NSQIP does not systematically collect data on patients undergoing intracranial endovascular intervention. Multivariable logistic regression evaluated predictors of any 30-day adverse event; variables screened included patient demographics, comorbidities, functional status, preoperative laboratory values, aneurysm location/complexity, and operative time. A predictive scale was constructed based on statistically significant independent predictors, which was validated using both NSQIP (2015-2016) and the Nationwide Inpatient Sample (NIS; 2002-2011).

RESULTS

The NSQIP unruptured aneurysm scale was proposed: 1 point was assigned for a bleeding disorder; 2 points for age 51-60 years, cardiac disease, diabetes mellitus, morbid obesity, anemia (hematocrit < 36%), operative time 240-330 minutes; 3 points for leukocytosis (white blood cell count > 12,000/μL) and operative time > 330 minutes; and 4 points for age > 60 years. An increased score was predictive of postoperative stroke or coma (NSQIP: p = 0.002, C-statistic = 0.70; NIS: p < 0.001, C-statistic = 0.61), a medical complication (NSQIP: p = 0.01, C-statistic = 0.71; NIS: p < 0.001, C-statistic = 0.64), and a nonroutine discharge (NSQIP: p < 0.001, C-statistic = 0.75; NIS: p < 0.001, C-statistic = 0.66) in both validation populations. Greater score was also predictive of increased odds of any adverse event, a major complication, and an extended hospitalization in both validation populations (p ≤ 0.03).

CONCLUSIONS

The NSQIP unruptured aneurysm scale may augment the risk stratification of patients undergoing microsurgical clipping of unruptured cerebral aneurysms.

Multimodal management of giant cerebral aneurysms: review of literature and case presentation

The pathophysiology of giant cerebral aneurysms renders them difficult to treat. Advances in technology have attempted to address any shortcomings associated with open surgery or endovascular therapies. Since the introduction of the flow diversion technique, the endovascular approach with flow diversion has become the first-line modality chosen to treat giant aneurysms. A subset of these giant aneurysms may persistent despite any treatment modality. Perhaps the best option for these recurrent and/or persistent giant aneurysms is to employ a multimodal approach-both surgical and endovascular-rather than any single technique to provide a curative result with favourable patient outcomes. This paper provides a review of the histopathology and treatment options for giant cerebral aneurysms. Additionally, an illustrative case is presented to highlight the unique challenges of a curative solution for giant cerebral aneurysms that persist despite initial treatment.

Quality of British and American Nationwide Quality of Care and Patient Safety Benchmarking Programs: Case Neurosurgery

BACKGROUND

Multiple nationwide outcome registries are utilized for quality benchmarking between institutions and individual surgeons.

OBJECTIVE

To evaluate whether nationwide quality of care programs in the United Kingdom and United States can measure differences in neurosurgical quality.

METHODS

This prospective observational study comprised 418 consecutive adult patients undergoing elective craniotomy at Helsinki University Hospital between December 7, 2011 and December 31, 2012.We recorded outcome event rates and categorized them according to British Neurosurgical National Audit Programme (NNAP), American National Surgical Quality Improvement Program (NSQIP), and American National Neurosurgery Quality and Outcomes Database (N2QOD) to assess the applicability of these programs for quality benchmarking and estimated sample sizes required for reliable quality comparisons.

RESULTS

The rate of in-hospital major and minor morbidity was 18.7% and 38.0%, respectively, and 30-d mortality rate was 2.4%. The NSQIP criteria identified 96.2% of major but only 38.4% of minor complications. N2QOD performed better, but almost one-fourth (23.2%) of all patients with adverse outcomes, mostly minor, went unnoticed. For NNAP, a sample size of over 4200 patients per surgeon is required to detect a 50.0% increase in mortality rates between surgeons. The sample size required for reliable comparisons between the rates of complications exceeds 600 patients per center per year.

CONCLUSION

The implemented benchmarking programs in the United Kingdom and United States fail to identify a considerable number of complications in a high-volume center. Health care policy makers should be cautious as outcome comparisons between most centers and individual surgeons are questionable if based on the programs.

Big Data Defined: A Practical Review for Neurosurgeons

BACKGROUND

Modern science and healthcare generate vast amounts of data, and, coupled with the increasingly inexpensive and accessible computing, a tremendous opportunity exists to use these data to improve care. A better understanding of data science and its relationship to neurosurgical practice will be increasingly important as we transition into this modern "big data" era.

METHODS

A review of the literature was performed for key articles referencing big data for neurosurgical care or related topics.

RESULTS

In the present report, we first defined the nature and scope of data science from a technical perspective. We then discussed its relationship to the modern neurosurgical practice, highlighting key references, which might form a useful introductory reading list.

CONCLUSIONS

Numerous challenges exist going forward; however, organized neurosurgery has an important role in fostering and facilitating these efforts to merge data science with neurosurgical practice.

Intraoperative neuromonitoring during microsurgical clipping for unruptured anterior choroidal artery aneurysm

OBJECTIVE

To investigate the safety and unexpected finding of the intraoperative neuromonitoring (IONM) including somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) during microsurgical clipping of an unruptured anterior choroidal artery (AChA) aneurysm.

PATIENTS AND METHODS

From January 2011 to March 2018, the neurophysiological, clinical, and radiological data of 115 patients who underwent microsurgical clipping for an unruptured AChA aneurysm under IONM were retrospectively analyzed. The incidence of ischemic complications after microsurgical clipping of unruptured AChA aneurysms as well as the false-negative rate, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of IONM during surgery were calculated.

RESULTS

Ischemic complications after the microsurgical clipping of an AChA aneurysm under IONM occurred in 7 of 115 patients (6.08%). Among them, 3 were symptomatic (2.6%). The false-negative rate of IONM for ischemic complications was 6.08% (7 patients). High specificity; 100% (95% confidence interval [95% CI] = 0.972-1.000), PPVs; 100% (95% CI = 0.055-1.000), and NPVs; 93% (95% CI = 0.945-0.973) with low sensitivity; 11.1% (95% CI = 0.006-0.111) were calculated.

CONCLUSIONS

IONM including transcranial MEP during microsurgical clipping of unruptured AChA aneurysm might have limited usefulness. Therefore, other MEP monitoring using direct cortical stimulation or modified transcranial methodology should be considered to compensate for it.

Anterior Cervical Corpectomy and Fusion Versus Anterior Cervical Discectomy and Fusion for Treatment of Multilevel Cervical Spondylotic Myelopathy: Insights from a National Registry

BACKGROUND

Anterior cervical discectomy and fusion (ACDF) is the most common procedure for single-level cervical spondylotic myelopathy (CSM); however, for multilevel CSM, some patients may also undergo anterior cervical corpectomy and fusion (ACCF). We sought to assess differences in clinical outcomes between patients undergoing ACDF and those undergoing ACCF for multilevel CSM.

METHODS

The National Surgical Quality Improvement Program (NSQIP) database was queried from 2007 to 2017 to identify patients diagnosed with CSM undergoing 1- or 2-level ACCF and 2- or 3-level ACDF. Three-to-one propensity scoring was used to match patients undergoing 1-level ACCF to those undergoing 2-level ACDF. Multivariable regression was performed to compare 30-day clinical outcomes between ACCF and ACDF recipients.

RESULTS

A total of 3708 patients undergoing 1-level ACCF (n = 729; 18.7%) or 2-level ACDF (n = 3179; 81.3%) were identified. On multivariable regression, 1-level ACCF was associated with significantly longer length of stay (coefficient, 0.79; 95% confidence interval [CI], 0.46-1.11; P < 0.001), longer operative time (coefficient, 19.01; 95% CI, 11.94-26.08; P < 0.001), decreased odds of readmissions (odds ratio [OR], 0.95; 95% CI, 0.91-0.99; P = 0.018), and increased odds of complications (OR, 1.02; 95% CI, 1.00-1.04; P = 0.028) compared with those undergoing 2-level ACDF. A total of 939 patients undergoing either 2-level ACCF (n = 348; 37.1%) or 3-level ACDF (n = 591; 62.9%) were identified. On multivariable regression, 2-level ACCF was associated with significantly longer length of stay (coefficient, 1.17; 95% CI, 0.55-1.79; P < 0.001) and increased risk of complications (OR, 1.05; 95% CI, 1.01-1.08; P = 0.004) compared with 3-level ACDF.

CONCLUSIONS

Our analyses indicate that ACCF may be associated with worse clinical outcomes than ACDF following multilevel treatment for CSM.

Impact of Dialysis on 30-Day Outcomes After Spinal Fusion Surgery for Pathologic Fractures: Insights from a National Quality Registry

BACKGROUND

Patients with chronic renal failure undergoing hemodialysis have been shown to have poor overall health, osteoporosis, and altered bone metabolism. However, the impact of hemodialysis on patient outcomes after spinal fusion remains unknown. We sought to assess the effect of dialysis on 30-day perioperative and postoperative outcomes after cervical and lumbar fusion for pathologic compression fractures.

METHODS

We queried the National Surgical Quality Improvement Program from 2009 to 2016 for patients undergoing cervical or lumbar fusion for compression fractures. Three-to-one propensity score matching using sex, age, body mass index, and number of operated levels was used to match patients not undergoing dialysis with those undergoing dialysis. Multivariable conditional regression was used to identify the association between dialysis and 30-day clinical outcomes, after adjusting for confounders.

RESULTS

A total of 48,492 patients undergoing cervical fusion were identified; 156 (0.32%) of these were on dialysis. On multivariable regression, dialysis dependency was associated with increased operative time (regression coefficient [coef.], 15.93; 95% CI, 0.4-31.5; P = 0.045), length of stay (coef. 6.06; 95% CI, 4.64-7.48; P < 0.001), 30-day readmissions (odds ratio [OR], 1.07; 95% CI, 1.02-1.12; P = 0.009), any complications (OR 1.08; 95% CI, 1.03-1.13; P = 0.002), and serious complications (OR, 1.08; 95% CI, 1.02-1.14; P = 0.012). A total of 25,417 patients undergoing lumbar fusion were identified; 51 of these (0.2%) were on dialysis. On multivariable regression, dialysis dependency was associated with significantly higher length of stay (coef. 2.98; 95% CI, 1.28-4.68; P < 0.001).

CONCLUSIONS

Our analyses indicated that dialysis dependency is associated with poor perioperative and postoperative outcomes after cervical/lumbar fusion for pathologic compression fractures.

Predictors of Unplanned Returns to the Operating Room within 30 Days in Neurosurgery: Insights from a National Surgical Registry

BACKGROUND

In the modern, increasingly pay-for-performance era, unplanned return to the operating room (ROR) is gaining attention as a surgical quality metric. However, large-scale data on the appropriateness and usefulness of this measure in neurosurgery are scarce.

OBJECTIVE

To provide a comprehensive description of all RORs after neurosurgical procedures in a national surgical registry and identify factors associated with ROR.

METHODS

We queried the American College of Surgeons National Surgical Quality Improvement Program multicenter database for patients undergoing neurosurgical procedures during 2012-2016. Multivariable logistic regression was conducted to identify factors associated with 30-day unplanned ROR after the 3 most common inpatient cranial and spinal operations: craniotomy for intra-axial neoplasm, convexity/falx meningioma, or skull base tumors; anterior cervical discectomy and fusion; and posterior lumbar decompression and posterior lumbar fusion.

RESULTS

A total of 193,459 cases were identified, of which 7067 (3.7%) had at least 1 unplanned ROR within 30 days after the index procedure (inpatient, 4.3%; outpatient, 1.5%). Overall, the most common reasons were wound complication/surgical site infection (0.7%), hematoma evacuation (0.6%), and repeat surgery (0.5%). On multivariable analysis, the relative amount of variation in reoperation risk was found to be 1%-24% for demographics, 1%-19% for comorbidities, 1%-6% for preoperative laboratory values, and 4%-58% for operative characteristics.

CONCLUSIONS

These findings may inform stakeholders on the optimal parameters that need to be taken into account when crafting, endorsing, and implementing quality metrics for neurosurgery that aim to assess surgical performance and reward or penalize hospitals and providers.

Procedural Clinical Complications, Case-Fatality Risks, and Risk Factors in Endovascular and Neurosurgical Treatment of Unruptured Intracranial Aneurysms: A Systematic Review and Meta-analysis

Importance

The risk of procedural clinical complications and the case-fatality rate (CFR) from preventive treatment of unruptured intracranial aneurysms varies between studies and may depend on treatment modality and risk factors.

Objective

To assess current procedural clinical 30-day complications and the CFR from endovascular treatment (EVT) and neurosurgical treatment (NST) of unruptured intracranial aneurysms and risk factors of clinical complications.

Data Sources

We searched PubMed, Excerpta Medica Database, and the Cochrane Database for studies published between January 1, 2011, and January 1, 2017.

Study Selection

Studies reporting on clinical complications, the CFR, and risk factors, including 50 patients or more undergoing EVT or NST for saccular unruptured intracranial aneurysms after January 1, 2000, were eligible.

Data Extraction and Synthesis

Per treatment modality, we analyzed clinical complication risk and the CFR with mixed-effects logistic regression models for dichotomous data. For studies reporting data on complication risk factors, we obtained risk ratios (RRs) or odds ratios (ORs) with 95% CIs and pooled risk estimates with weighted random-effects models.

Main Outcomes and Measures

Clinical complications within 30 days and the CFR.

Results

We included 114 studies (106 433 patients with 108 263 aneurysms). For EVT (74 studies), the pooled clinical complication risk was 4.96% (95% CI, 4.00%-6.12%), and the CFR was 0.30% (95% CI, 0.20%-0.40%). Factors associated with complications from EVT were female sex (pooled OR, 1.06 [95% CI, 1.01-1.11]), diabetes (OR, 1.81 [95% CI, 1.05-3.13]), hyperlipidemia (OR, 1.76 [95% CI, 1.3-2.37]), cardiac comorbidity (OR, 2.27 [95% CI, 1.53-3.37]), wide aneurysm neck (>4 mm or dome-to-neck ratio >1.5; OR, 1.71 [95% CI, 1.38-2.11]), posterior circulation aneurysm (OR, 1.42 [95% CI, 1.15-1.74]), stent-assisted coiling (OR, 1.82 [95% CI, 1.16-2.85]), and stenting (OR, 3.43 [95% CI, 1.45-8.09]). For NST (54 studies), the pooled complication risk was 8.34% (95% CI, 6.25%-11.10%) and the CFR was 0.10% (95% CI, 0.00%-0.20%). Factors associated with complications from NST were age (OR per year increase, 1.02 [95% CI, 1.01-1.02]), female sex (OR, 0.43 [95% CI, 0.32-0.85]), coagulopathy (OR, 2.14 [95% CI, 1.13-4.06]), use of anticoagulation (OR, 6.36 [95% CI, 2.55-15.85]), smoking (OR, 1.95 [95% CI, 1.36-2.79]), hypertension (OR, 1.45 [95% CI, 1.03-2.03]), diabetes (OR, 2.38 [95% CI, 1.54-3.67]), congestive heart failure (OR, 2.71 [95% CI, 1.57-4.69]), posterior aneurysm location (OR, 7.25 [95% CI, 3.70-14.20]), and aneurysm calcification (OR, 2.89 [95% CI, 1.35-6.18]).

Conclusions and Relevance

This study identifies risk factors for procedural complications. Large data sets with individual patient data are needed to develop and validate prediction scores for absolute complication risks and CFRs from EVT and NST modalities.

Thirty-day postoperative morbidity and mortality after temporal lobectomy for medically refractory epilepsy

OBJECTIVE

Temporal lobectomy is a well-established treatment modality for the management of medically refractory epilepsy in appropriately selected patients. The aim of this study was to assess 30-day morbidity and mortality after temporal lobectomy in cases registered in a national database.

METHODS

A retrospective cohort analysis was conducted using a multiinstitutional surgical registry compiled between 2006 and 2014. The authors identified patients who underwent anterior temporal lobectomy and/or amygdalohippocampectomy for a primary diagnosis of intractable epilepsy. Univariate and multivariable analyses with regard to patient demographics, comorbidities, operative characteristics, and 30-day outcomes were applied.

RESULTS

A total of 216 patients were included in the study. The median age was 38 years and 46% of patients were male. The median length of stay was 3 days and the 30-day mortality rate was 1.4%. Fourteen patients (6.5%) developed at least one major complication. Return to the operating room was observed in 7 patients (3.2%). Readmission within 30 days and discharge to a location other than home were available for 2011–2014 (n = 155) and occurred in 11% and 10.3% of patients, respectively. Multivariable regression analysis revealed that increasing age was an independent predictor of discharge disposition other than home and that male sex was a significant risk factor for the development of a major complication. Interestingly, the presence of the attending neurosurgeon and a resident during the procedure was significantly associated with decreased odds of prolonged length of stay (i.e., > 75th percentile [5 days]) and discharge to a location other than home.

CONCLUSIONS

Using a multiinstitutional surgical registry, 30-day outcome data after temporal lobectomy for medically intractable epilepsy demonstrates a mortality rate of 1.4%, a major complication rate of 6.5%, and a readmission rate of 11%. Temporal lobectomy is an extremely effective therapy for seizures originating there—however, surgical intervention must be weighed against its morbidity and mortality outcomes.

Treatment of Large and Giant Middle Cerebral Artery Aneurysms: Risk Factors for Unfavorable Outcomes

OBJECTIVE

This study aimed to assess the clinical and radiologic outcomes after neurosurgical treatment of large and giant aneurysms of the middle cerebral artery (MCA). In addition, we aimed to identify risk factors for unfavorable outcomes.

METHODS

This retrospective study included 105 patients with 106 large or giant MCA aneurysms treated with neurosurgical methods, including microsurgery and endovascular treatment, over a 15-year period.

RESULTS

The mean aneurysm size was 15.3 ± 7.1 mm. Ten (9.4%) were giant aneurysms. The MCA bifurcation was the most common aneurysm site, followed by the MCA trunk and distal MCA. Aneurysm clipping was the most common treatment method, followed by clipping or trapping with bypass surgery and endovascular treatment. However, acute cerebral infarction was the most common complication (16.0%), poor outcomes (modified Rankin Scale score, 3-6) developed in 12.3% of aneurysms after treatment, and 6.6% of treated aneurysms needed retreatment. Multivariate analysis showed that independent risk factors for acute cerebral infarction after treatment were aneurysms located on the MCA trunk and 2 or more underlying diseases. Initial presentation with subarachnoid hemorrhage and complications during treatment were independent risk factors for poor outcomes. In addition, endosaccular coiling was an independent risk factor for retreatment.

CONCLUSIONS

Neurosurgical management should be considered a priority for large and giant MCA aneurysms because of the high rupture rate and clinical symptoms. However, treatment outcomes remain unsatisfactory. Therefore, tailored management with consideration of risk factors for unfavorable outcomes should be implemented.

Microsurgical Clipping of Unruptured Intracranial Aneurysms: A Single Surgeon's Experience over 16 Years

BACKGROUND

Unruptured intracranial aneurysms (UIAs) have become an issue of greater significance as their detection rates have increased over the years. We present the overall experience of microsurgical clipping of unruptured aneurysms by a single surgeon over a period of more than 16 years.

METHODS

The clinical and radiologic data were reviewed retrospectively. Clinical outcome at follow-up was assessed with Glasgow Outcome Scale, and angiograms were reviewed for the degree of occlusion.

RESULTS

One hundred ninety-six patients with 221 UIAs were included in the analysis. The median age of patients was 54 years, with a female preponderance. Eighty-two percent of the patients had chronic headache on presentation. Middle cerebral artery aneurysms (32.2%) and posterior-inferior-cerebellar-artery aneurysms (46.1%) were most common in the anterior and posterior circulation, respectively. The perioperative complication rate was 17.3%. The overall surgical morbidity and mortality were 2.1% and 1.5%, respectively. With median follow-up of 11.3 months, 82% of patients were almost asymptomatic with a complete occlusion rate of 94%. The proportion of UIAs being coiled has significantly increased in the last decade, with a concomitant increase in the risk of poor clinical outcome after surgery.

CONCLUSION

Surgical clipping is effective and can provide a good long-term outcome. The most commendable consequence that it provides is a better long-term occlusion rate. The experience of the individual surgeon is important for a superior and enduring overall outcome. An increase in the rate of coiling in recent years has affected the outcome rate after surgery that calls for further evaluation.