PACS-integrated machine learning breast density classifier: clinical validation.

OBJECTIVE: To test the performance of a novel machine learning-based breast density tool. The tool utilizes a convolutional neural network to predict the BI-RADS based density assessment of a study. The clinical density assessments of 33,000 mammographic examinations (164,000 images) from one academic medical center (Site A) were used for training. MATERIALS AND METHODS: This was an IRB approved HIPAA compliant study performed at two academic medical centers. The validation data set was composed of 500 studies from one site (Site A) and 700 from another (Site B). At Site A, each study was assessed by three breast radiologists and the majority (consensus) assessment was used as truth. At Site B, if the tool agreed with the clinical reading, then it was considered to have correctly predicted the clinical reading. In cases where the tool and the clinical reading disagreed, then the study was evaluated by three radiologists and the consensus reading was used as the clinical reading. RESULTS: For the classification into the four categories of the Breast Imaging Reporting and Data System (BI-RADS®), the AI classifier had an accuracy of 84.6% at Site A and 89.7% at Site B. For binary classification (dense vs. non-dense), the AI classifier had an accuracy of 94.4% at Site A and 97.4% at Site B. In no case did the classifier disagree with the consensus reading by more than one category. CONCLUSIONS: The automated breast density tool showed high agreement with radiologists' assessments of breast density.

FDA's dilemma with the aducanumab approval: public pressure and hope, surrogate markers and efficacy, and possible next steps.

Accelerating Food and Drug Administration (FDA) product approval to market based on surrogate markers in the absence of proven efficacy creates a risk of adverse outcomes for affected patients, even in response to a life-threatening condition, such as in this case, Alzheimer's disease. FDA's recent unexpected approval of aducanumab, despite the unified opposition of its own highly respected advisory committee after the early termination of two efficacy trials, creates the potential risk of adverse effects and lack of clinical efficacy at very high costs. In view of these concerns, a thorough review of the issues and pressures that led to this decision is worth the careful consideration of the clinical and scientific communities with regard to whether this approval represents a calculated and balanced compassionate decision versus a disturbing precedent.

Clinical Characteristics and Pharmacological Management of COVID-19 Vaccine-Induced Immune Thrombotic Thrombocytopenia With Cerebral Venous Sinus Thrombosis: A Review.

Importance: The COVID-19 pandemic saw one of the fastest developments of vaccines in an effort to combat an out-of-control pandemic. The 2 most common COVID-19 vaccine platforms currently in use, messenger RNA (mRNA) and adenovirus vector, were developed on the basis of previous research in use of this technology. Postauthorization surveillance of COVID-19 vaccines has identified safety signals, including unusual cases of thrombocytopenia with thrombosis reported in recipients of adenoviral vector vaccines. One of the devastating manifestations of this syndrome, termed vaccine-induced immune thrombotic thrombocytopenia (VITT), is cerebral venous sinus thrombosis (CVST). This review summarizes the current evidence and indications regarding biology, clinical characteristics, and pharmacological management of VITT with CVST. Observations: VITT appears to be similar to heparin-induced thrombocytopenia (HIT), with both disorders associated with thrombocytopenia, thrombosis, and presence of autoantibodies to platelet factor 4 (PF4). Unlike VITT, HIT is triggered by recent exposure to heparin. Owing to similarities between these 2 conditions and lack of high-quality evidence, interim recommendations suggest avoiding heparin and heparin analogues in patients with VITT. Based on initial reports, female sex and age younger than 60 years were identified as possible risk factors for VITT. Treatment consists of therapeutic anticoagulation with nonheparin anticoagulants and prevention of formation of autoantibody-PF4 complexes, the latter being achieved by administration of high-dose intravenous immunoglobin (IVIG). Steroids, which can theoretically inhibit the production of new antibodies, have been used in combination with IVIG. In severe cases, plasma exchange should be used for clearing autoantibodies. Monoclonal antibodies, such as rituximab and eculizumab, can be considered when other therapies fail. Routine platelet transfusions, aspirin, and warfarin should be avoided because of the possibility of worsening thrombosis and magnifying bleeding risk. Conclusions and Relevance: Adverse events like VITT, while uncommon, have been described despite vaccination remaining the most essential component in the fight against the COVID-19 pandemic. While it seems logical to consider the use of types of vaccines (eg, mRNA-based administration) in individuals at high risk, treatment should consist of therapeutic anticoagulation mostly with nonheparin products and IVIG.

Inactivated Four-Factor Prothrombin Complex Concentrate Dosing Practices for Reversal of Warfarin-Related Intracranial Hemorrhage.

BACKGROUND/OBJECTIVE: Inactivated four-factor prothrombin complex concentrate (I4F-PCC, Kcentra®) has become an important agent for the urgent or emergent reversal of bleeding associated with vitamin K antagonists such as warfarin. There is recognized inter-institutional variability with the use of I4F-PCC, especially as it relates to dosing practices. We sought to characterize variations in I4F-PCC dosing practices and their impact on patient outcomes and describe overall real-world clinical practice surrounding I4F-PCC utilization in the context of the management of warfarin-related intracranial hemorrhage (ICH). METHODS: This is a multicenter retrospective pragmatic registry study of adult patients admitted at a participating study site between January 1, 2014, and December 31, 2015, who received I4F-PCC for reversal of warfarin-related ICH. Practices around warfarin-related ICH reversal in context of I4F-PCC utilization are described, including repeat I4F-PCC dosing, adjunctive reversal agents, and dose rounding policies (i.e., rounding doses to nearest vial size vs preparing exact/unrounded doses). All research was approved by local human investigation committees at each institution. RESULTS: Seventeen institutions contributed data on 528 patients to this registry. These institutions were primarily urban centers (74%), located in the southeast USA (47%), with Level 1 Trauma designation (79%), and with Comprehensive Stroke Center designation (74%). Most patients included in the study had sustained a non-traumatic ICH (68%), had a median admission GCS of 14 (IQR 7-15), and were receiving warfarin for atrial fibrillation (57.4%). There was substantial time latency between baseline INR and I4F-PCC (median 2.4 h, IQR 1.4-4.5 h). Most patients received adjunctive reversal agents, including vitamin K (89.5%) and fresh frozen plasma (FFP) (31.9%). A smaller proportion (6.0%) of patients received repeat I4F-PCC dosing. The median ICU length of stay (LOS) was 3 days (IQR 2-7 days), median hospital LOS was 6 days (IQR 3-12 days), and overall mortality rate was 28.8%. For institutions rounding doses to the nearest vial size, the first post-I4F-PCC dose INR was statistically but not clinically significantly lower than for institutions without vial size dose rounding, with comparable degrees of INR reduction from baseline. No differences were observed between dose rounding cohorts in adverse effects, ICU or hospital LOS, modified Rankin score at discharge, or mortality rates. CONCLUSIONS: Most patients received single doses of I4F-PCC, with adjunctive reversal agents and rounding doses to vial size. The time difference from baseline INR to factor product administration is a potential opportunity for process improvement in the management of warfarin-related ICH.

Expanded Access Programs, compassionate drug use, and Emergency Use Authorizations during the COVID-19 pandemic.

The US Food and Drug Administration (FDA) Expanded Access (EA) Program, which allows for compassionate uses of unapproved therapeutics and diagnostics outside of clinical trials, has gained significant traction during the Coronavirus 2019 (COVID-19) pandemic. While development of vaccines has been the major focus, uncertainties around new vaccine safety and effectiveness have spawned interest in other pharmacological options. Experimental drugs can also be approved under the FDA Emergency Use Authorization (EUA) program, designed to combat infectious disease and other threats. Here, we review the US experience in 2020 with pharmacological EA and EUA approvals during the pandemic. We also provide a description of, and clinical rationale for, each of the EA- or EUA-approved drugs (e.g. remdesivir, convalescent plasma, propofol 2%, hydroxychloroquine, ruxolitinib, bamlanivimab, baricitinib, casirivimab plus imdevimab) during the pandemic and concluding reflections on the EA program and its potential future uses.

Adjuvant Analgesic Use in the Critically Ill: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis addresses the efficacy and safety of nonopioid adjunctive analgesics for patients in the ICU. DATA SOURCES: We searched PubMed, Embase, the Cochrane Library, CINAHL Plus, and Web of Science. STUDY SELECTION: Two independent reviewers screened citations. Eligible studies included randomized controlled trials comparing efficacy and safety of an adjuvant-plus-opioid regimen to opioids alone in adult ICU patients. DATA EXTRACTION: We conducted duplicate screening of citations and data abstraction. DATA SYNTHESIS: Of 10,949 initial citations, we identified 34 eligible trials. These trials examined acetaminophen, carbamazepine, clonidine, dexmedetomidine, gabapentin, ketamine, magnesium sulfate, nefopam, nonsteroidal anti-inflammatory drugs (including diclofenac, indomethacin, and ketoprofen), pregabalin, and tramadol as adjunctive analgesics. Use of any adjuvant in addition to an opioid as compared to an opioid alone led to reductions in patient-reported pain scores at 24 hours (standard mean difference, -0.88; 95% CI, -1.29 to -0.47; low certainty) and decreased opioid consumption (in oral morphine equivalents over 24 hr; mean difference, 25.89 mg less; 95% CI, 19.97-31.81 mg less; low certainty). In terms of individual medications, reductions in opioid use were demonstrated with acetaminophen (mean difference, 36.17 mg less; 95% CI, 7.86-64.47 mg less; low certainty), carbamazepine (mean difference, 54.69 mg less; 95% CI, 40.39-to 68.99 mg less; moderate certainty), dexmedetomidine (mean difference, 10.21 mg less; 95% CI, 1.06-19.37 mg less; low certainty), ketamine (mean difference, 36.81 mg less; 95% CI, 27.32-46.30 mg less; low certainty), nefopam (mean difference, 70.89 mg less; 95% CI, 64.46-77.32 mg less; low certainty), nonsteroidal anti-inflammatory drugs (mean difference, 11.07 mg less; 95% CI, 2.7-19.44 mg less; low certainty), and tramadol (mean difference, 22.14 mg less; 95% CI, 6.67-37.61 mg less; moderate certainty). CONCLUSIONS: Clinicians should consider using adjunct agents to limit opioid exposure and improve pain scores in critically ill patients.

Defects in Processes of Care for Pharmacologic Prophylaxis Are Common Among Neurosurgery Patients Who Develop In-Hospital Postoperative Venous Thromboembolism.

BACKGROUND: Venous thromboembolism (VTE) is a cause of considerable morbidity and mortality in hospitalized patients. An evidence-based algorithm was developed and implemented at our institution to guide perioperative VTE prophylaxis management. OBJECTIVE: We evaluated compliance with prescription of risk-appropriate VTE prophylaxis and administration of prescribed VTE prophylaxis in neurosurgery patients. METHODS: This was a retrospective analysis of postoperative neurosurgery patients at a single institution with subsequent diagnosis of acute VTE during their inpatient stay. Descriptive statistics were used to characterize pharmacologic VTE prophylaxis and prescribing patterns. RESULTS: The incidence of VTE in our neurosurgery population was 248/13,913 (1.8%). Of the 123 patients, the median time to VTE diagnosis was 96 hours after surgery (interquartile range [IQR], 58-188 hours). A total of 108 patients (87.8%) were prescribed risk-appropriate VTE prophylaxis, among whom 61 (56.5%) received all doses as prescribed. Fifty-three patients (43.1%) missed ≥1 dose of prescribed prophylaxis and the median missed doses was 3 (IQR, 0-3). The median time to first dose of pharmacologic VTE prophylaxis was 42 hours (IQR, 28-51). More than half (n = 63, 51.2%) of the VTE risk assessments contained ≥1 error, of which 15 (23.8%) would have resulted in a change in recommendation. CONCLUSIONS: Our evidence-based VTE prophylaxis algorithm was not accurately completed in more than half of patients. Many patients who developed VTE had a defect in their VTE prophylaxis management during their inpatient stay. Research to improve optimal VTE prevention practice in neurosurgery patients is needed.

Contrast-Enhanced Mammography: A Scientific Review.

In this paper we provide an overview of contrast-enhanced mammography (CEM) and a review of the published literature in order to provide a picture of the current state of the evidence on the performance of CEM. Clinical research was fairly sparse following the demonstration of the technique in research subjects about 18 years ago, but the number of publications rapidly increased following commercialization 9 years ago, and even more so in the last 5 years. Initial studies compared CEM with mammography, and clearly showed that CEM could detect cancers not visible on mammography. More recent studies have primarily focused on comparing the performance of CEM with contrast-enhanced magnetic resonance imaging (MRI) in selected cohorts. These studies have almost uniformly shown CEM and MRI to have similar sensitivities, with sensitivity and accuracy showing more variability from study to study. With increasing clinical use, a large number of retrospective reviews of CEM have appeared, showing utility of CEM in the diagnostic clinical setting. Most recently, a small number of papers have been published looking at CEM for high-risk and dense breast screening, two potentially large applications of the technique, showing it to outperform mammography in both populations. CEM has clearly been shown to have clinical utility, but more prospective studies, including screening studies, are needed to further evaluate its performance, especially in comparison with MRI.

Current Practices of Intraventricular Antibiotic Therapy in the Treatment of Meningitis and Ventriculitis: Results from a Multicenter Retrospective Cohort Study.

BACKGROUND: Central nervous system (CNS) infections are particularly prevalent in the adult neurocritical care patient population and are associated with significant morbidity and mortality. Factors relevant to the nature of CNS infections pose significant challenges to clinicians treating afflicted patients. Intraventricular (IVT) administration of antibiotics may offer several benefits over systemic therapy; however, the outcomes and current practices of such treatments are poorly described in the literature. OBJECTIVE: To describe current practices and outcomes of patients receiving intraventricular antibiotic treatment for CNS infections in neurological intensive care units of academic medical centers nationwide. METHODS: A retrospective cohort study was conducted on patients admitted to intensive care units who received IVT antibiotic treatment at participating centers in the USA between January 01, 2003, and December 31, 2013. Clinical and laboratory parameters, microbiology, surgical and antimicrobial management, and treatment outcomes were collected and described. RESULTS: Of the 105 patients included, all received systemic antimicrobial therapy along with at least one dose of IVT antimicrobial agents. Intraventricular vancomycin was used in 52.4% of patients. The average dose was 12.2 mg/day for a median duration of 5 days. Intraventricular aminoglycosides were used in 47.5% of the patients, either alone or in combination with IVT vancomycin. The average dose of gentamicin/tobramycin was 6.7 mg/day with a median duration of 6 days. Overall mortality was 18.1%. Cerebrospinal fluid (CSF) culture sterilization occurred in 88.4% of the patients with a rate of recurrence or persistence of positive cultures of 9.5%. CONCLUSION: Intraventricular antimicrobial agents resulted in a high CSF sterilization rate. Contemporary use of this route typically results in a treatment duration of less than a week. Prospective studies are needed to establish the optimal patient population, as well as the efficacy and safety of this route of administration.

Correction to: Phase 2 Open-Label Trial Investigating Percutaneous Laser Ablation for Treatment of Early-Stage Breast Cancer: MRI, Pathology, and Outcome Correlations.

The article "Phase 2 Open-Label Trial Investigating Percutaneous Laser Ablation for Treatment of Early-Stage Breast Cancer: MRI, Pathology, and Outcome Correlations", written by Barbara Schwartzberg et al., was originally published electronically on the publisher's internet portal (currently SpringerLink) on July 9, 2018, without open access.

Phase 2 Open-Label Trial Investigating Percutaneous Laser Ablation for Treatment of Early-Stage Breast Cancer: MRI, Pathology, and Outcome Correlations.

BACKGROUND: An institutional review board-approved, multicenter clinical trial was designed to determine the efficacy and outcome of percutaneous laser ablation (PLA) in the treatment of invasive ductal breast carcinoma (IDC). Post-ablation magnetic resonance imaging (MRI) was compared with surgical pathology in evaluation of residual post-ablation IDC and ductal carcinoma in situ. METHODS: Patients with a single focus of IDC 20 mm or smaller by pre-ablation MRI were treated with PLA. The patients underwent a 28-day post-ablation MRI, followed by surgical resection. Cell viability criteria were applied to pre- and post-ablation pathology specimens, which evaluated hematoxylin-eosin (H&E), cytokeratin (CK) 8/18, estrogen receptor, and Ki67 staining patterns. RESULTS: In this study, 61 patients were reported as the intention-to-treat cohort for determination of PLA efficacy. Of these 61 patients, 51 (84%) had complete tumor ablation confirmed by pathology analysis. One subject's MRI imaging was not performed per protocol, which left 60 subjects evaluable for MRI pathology correlation. Five patients (8.3%) had residual IDC shown by both MRI and pathology. Post-ablation discordance was noted between MRI and pathology, with four patients (6.7%) false-positive and four patients (6.7%) false-negative. The negative predictive value (NPV) of MRI for all the patients was 92.2% (95% confidence interval [CI], 71.9-91.9%). Of the 47 patients (97.9%) with tumors 15 mm or smaller, 46 were completely ablated, with an MRI NPV of 97.7% (95% CI, 86.2-99.9%). CONCLUSIONS: Percutaneous laser ablation is a potential alternative to surgery for treatment of early-stage IDC. Strong correlations exist between post-ablation MRI and pathologic alterations in CK8/18, ER, and Ki67 staining.

Antiepileptic drugs in critically ill patients.

BACKGROUND: The incidence of seizures in intensive care units ranges from 3.3% to 34%. It is therefore often necessary to initiate or continue anticonvulsant drugs in this setting. When a new anticonvulsant is initiated, drug factors, such as onset of action and side effects, and patient factors, such as age, renal, and hepatic function, should be taken into account. It is important to note that the altered physiology of critically ill patients as well as pharmacological and nonpharmacological interventions such as renal replacement therapy, extracorporeal membrane oxygenation, and target temperature management may lead to therapeutic failure or toxicity. This may be even more challenging with the availability of newer antiepileptics where the evidence for their use in critically ill patients is limited. MAIN BODY: This article reviews the pharmacokinetics and pharmacodynamics of antiepileptics as well as application of these principles when dosing antiepileptics and monitoring serum levels in critically ill patients. The selection of the most appropriate anticonvulsant to treat seizure and status epileptics as well as the prophylactic use of these agents in this setting are also discussed. Drug-drug interactions and the effect of nonpharmacological interventions such as renal replacement therapy, plasma exchange, and extracorporeal membrane oxygenation on anticonvulsant removal are also included. CONCLUSION: Optimal management of antiepileptic drugs in the intensive care unit is challenging given altered physiology, polypharmacy, and nonpharmacological interventions, and requires a multidisciplinary approach where appropriate and timely assessment, diagnosis, treatment, and monitoring plans are in place.

Comparison of Contrast-Enhanced Mammography and Contrast-Enhanced Breast MR Imaging.

Contrast-enhanced mammography (CEM) is a contrast-enhanced modality for breast cancer detection that utilizes iodinated contrast and dual-energy imaging performed on a digital mammography unit with only slight modifications. It is approved by the US Food and Drug Administration, commercially available, and in routine clinical use at centers around the world. It has similar sensitivity and specificity to MR Imaging and has advantages in terms of cost, patient acceptability, and examination time. MR Imaging has some advantages compared with CEM, especially in its ability to image the complete axilla and the chest wall.

Initial Experience of Tomosynthesis-Guided Vacuum-Assisted Biopsies of Tomosynthesis-Detected (2D Mammography and Ultrasound Occult) Architectural Distortions.

OBJECTIVE: As experience and aptitude in digital breast tomosynthesis (DBT) have increased, radiologists are seeing more areas of architectural distortion (AD) on DBT images compared with standard 2D mammograms. The purpose of this study is to report our experience using tomosynthesis-guided vacuum-assisted biopsies (VABs) for ADs that were occult at 2D mammography and ultrasound and to analyze the positive predictive value for malignancy. MATERIALS AND METHODS: We performed a retrospective review of 34 DBT-detected ADs that were occult at mammography and ultrasound. RESULTS: We found a positive predictive value of 26% (nine malignancies in 34 lesions). Eight of the malignancies were invasive and one was ductal carcinoma in situ. The invasive cancers were grade 1 (4/8; 50%), grade 2 (2/8; 25%), or grade 3 (1/8; 13%); information about one invasive cancer was not available. The mean size of the invasive cancers at pathologic examination was 7.5 mm (range, 6-30 mm). CONCLUSION: Tomosynthesis-guided VAB is a feasible method to sample ADs that are occult at 2D mammography and ultrasound. Tomosynthesis-guided VAB is a minimally invasive method that detected a significant number of carcinomas, most of which were grade 1 cancers. Further studies are needed.

Contrast Enhanced Spectral Mammography: A Review.

Contrast-enhanced spectral mammography (CESM) provides low-energy 2D mammographic images comparable to standard digital mammography and a post-contrast recombined image to assess tumor neovascularity similar to magnetic resonance imaging (MRI). The utilization of CESM in the United States is currently low but could increase rapidly given many potential indications for clinical use. This article discusses historical background and literature review of indications and diagnostic accuracy of CESM to date. CESM is a growing technique for breast cancer detection and diagnosis that has levels of sensitivity and specificity on par with contrast-enhanced breast MRI. Because of its similar performance and ease of implementation, CESM is being adopted for multiple indications previously reserved for MRI, such as problem-solving, disease extent in newly diagnosed patients, and evaluating the treatment response of neoadjuvant chemotherapy.

Ketamine infusion for refractory status epilepticus: A case report of cardiac arrest.

BACKGROUND: Refractory status epilepticus (RSE) has a high mortality rate and is often difficult to treat. When traditional therapies fail ketamine may be considered. There are limited reports of adverse cardiac events with the use of ketamine for RSE and no reports of cardiac arrest in this context. OBJECTIVE: Evaluate the occurrence of cardiac arrhythmias associated with the use of ketamine for RSE. METHODS: Retrospective chart review of nine patients who underwent ketamine infusion for RSE. RESULTS: Etiology of refractory status epilepticus included autoimmune/infectious process (Zeiler et al., 2014), ischemic stroke (Bleck, 2005) and subarachnoid hemorrhage (Bleck, 2005). Of the nine patients who received ketamine, two had documented cardiac events; one remained clinically stable and the other developed multiple arrhythmias, including recurrent episodes of asystole. Once ketamine was discontinued the latter patient stabilized with the addition of anti arrhythmic therapy. CONCLUSION: Ketamine is utilized to treat refractory status epilepticus, but should be used with caution in patients with subarachnoid hemorrhage, as there may be an increased risk of life threatening arrhythmias and cardiac arrest.

Disparities in hypertension and cardiovascular disease in blacks: The critical role of medication adherence.

Blacks are two to three times as likely as whites to die of preventable heart disease and stroke. Declines in mortality from heart disease have not eliminated racial disparities. Control and effective treatment of hypertension, a leading cause of cardiovascular disease, among blacks is less than in whites and remains a challenge. One of the driving forces behind this racial/ethnic disparity is medication nonadherence whose cause is embedded in social determinants. Eight practical approaches to addressing medication adherence with the potential to attenuate disparities were identified and include: (1) patient engagement strategies, (2) consumer-directed health care, (3) patient portals, (4) smart apps and text messages, (5) digital pillboxes, (6) pharmacist-led engagement, (7) cardiac rehabilitation, and (8) cognitive-based behavior. However, while data suggest that these strategies may improve medication adherence, the effect on ameliorating racial/ethnic disparities is not certain. This review describes the relationship between disparities and medication adherence, which likely plays a role in persistent disparities in cardiovascular morbidity and mortality.

Impact of intraoperative cefazolin on postoperative seizures after elective repair of unruptured cerebral aneurysm.

PURPOSE: The impact of intraoperative cefazolin on postoperative seizures after elective repair of an unruptured cerebral aneurysm was evaluated. METHODS: Chart review of a prospectively accrued database was performed for patients admitted from January 1, 2003, through December 31, 2013. Patients were included in the study if they underwent elective repair of an unruptured aneurysm with surgical clipping or wrapping. The primary objective was to determine if the use of cefazolin increased patients' odds of having a seizure within six hours of surgical intervention. Univariate comparisons were conducted on all variables for patients who received cefazolin and patients who were treated with other antibiotics. Multivariable logistic regression was performed to assess the impact of cefazolin administered intraoperatively on postoperative seizures, while accounting for other covariates. RESULTS: Of the 520 patients included, 53 (10.2%) patients developed seizures within six hours after surgery. A total of 439 (84.4%) patients received cefazolin intraoperatively. There were no differences in baseline characteristics between the patients who received cefazolin compared with those who did not. The frequency of seizures did not significantly differ between patients treated with cefazolin versus other antibiotics (11.2% versus 4.9%, respectively; p = 0.08). Multivariable regression revealed that the use of cefazolin did not increase the odds of having a seizure postoperatively compared with patients treated with other antibiotics (odds ratio, 2.4; 95% confidence interval, 0.82-7.15). CONCLUSION: No relationship was found between the intraoperative use of cefazolin and the development of seizures during the six hours after the repair of unruptured cerebral aneurysms.