The Enterprise stent still useful after all these years.

BACKGROUND: The Enterprise stent (Codman Neuro, Massachusetts, USA) received Food and Drug Administration (FDA) approval in 2007 for stent-assisted coiling (SAC). Since its introduction, newer stents and devices for aneurysm treatment have been developed resulting in a shift in the utilization of this stent from SAC to other off-label indications. OBJECTIVE: To describe our experience with the Enterprise stent being used for SAC and other off-label indications. METHODS: This is a multi-center retrospective review of the use of the Enterprise stent between 2018 and 2023. All patients in which the Enterprise stent was successfully deployed were included in the study. RESULTS: Our study cohort comprised of 194 patients, mostly females (n = 112, 57.7%), with a mean age of 63.2 years ± 14.3. The Enterprise stent was used for SAC in only 24 (12.4%) patients and was used for rescue stenting in stroke in 101 patients (52.1%), treatment of intracranial stenosis in 53 patients (27.3%), treatment of in-stent stenosis in 1 patient (0.5%), and for treatment of dissections in 15 patients (7.7%). From 2018 to 2023, the use of Enterprise stents for SAC significantly decreased (p < 0.0001) while the use of Enterprise stents for non-SAC purposes was insignificantly variable (p = 0.05). CONCLUSION: Our study shows that the Enterprise stent remains a reliable tool in neuroendovascular procedures, even if its original intended use has been supplanted by other devices.

Artificial intelligence improves transfer times and ischemic stroke workflow metrics.

INTRODUCTION: Rapid initiation of mechanical thrombectomy (MT) for the treatment of large-vessel occlusion (LVO) critically improves patient outcomes. Artificial intelligence algorithms aid in the identification of LVOs and improve door to puncture times as well as patient transfer times. OBJECTIVES: We aimed to determine whether the implementation of an LVO detection algorithm that provides immediate active notification to the thrombectomy team provider's cell phone would improve ischemic stroke workflow at our institution and aid in patient transfer from outlying hospitals when compared to our prior system of passive computed tomography perfusion software analysis and radiologist interpretation and notification. METHODS: A retrospective review of our institutional thrombectomy registry was performed for all patients who underwent MT between January 2020 and March 2022. Demographic, radiographic, and stroke workflow metrics and notification times were collected. Transfer times and stroke metrics were compared pre- and post-implementation of the Viz.ai (Viz.ai, San Francisco, California, USA) smartphone application. RESULTS: Two hundred sixty-two patients underwent MT during the study period. Door-to-puncture time decreased 15 min (p = 0.009) after the implementation of Viz.ai at our Comprehensive Stroke Center. Transfer time from outside hospitals that implemented Viz.ai was reduced by 37 min (p = 0.04). There was no significant change in transfer time over the same time period in outlying hospitals that did not implement the Viz.ai software. CONCLUSION: Active notification of the neurosurgical team significantly reduces patient transfer time and initiation of MT.

Post-operative weight loss in venous sinus stenting patients: A multi-center review, systematic review, and meta-analysis.

INTRODUCTION: Idiopathic intracranial hypertension (IIH) can result in headaches, pulsatile tinnitus, papilledema, and other neurological symptoms. Weight loss can alleviate some symptoms of IIH. This study aims to investigate the effect of venous sinus stenting on post-operative weight and body mass index (BMI) changes among IIH patients. The secondary objective is to investigate the relationship between post-operative weight changes and papilledema resolution. METHODS: Patients with papilledema undergoing venous sinus stenting for IIH were retrospectively reviewed from two comprehensive North American cerebrovascular centers. Patient demographics, surgical course, post-operative outcomes, and weight were analyzed. A systematic review and meta-analysis of post-operative weight in stented IIH patients was conducted. RESULTS: Twenty-eight patients with a diagnosis of IIH and papilledema who underwent venous sinus stenting were identified across two institutions. Patients had a mean pre-operative weight of 103.2 kg, which decreased to 101.5 kg at 3-month follow up (p = 0.0757). Patients at 6-month follow-up saw a weight decrease to 97.4 kg (p = 0.0066). Patients who saw papilledema resolution saw a mean greater decrease in weight (-4.5%) at 6-month follow up than those whose papilledema did not resolve (-1.7%), although this was insignificant (p = 0.1091). A total of 41 patients were included in the meta-analysis. Patients had an average of 1.1 increase in BMI at 3-month follow up. CONCLUSIONS: This study shows that venous sinus stenting leads to modest weight reduction in IIH patients, and those with resolved papilledema experience slightly greater weight loss. Further research is necessary to determine the clinical significance of these findings.

Comparison of pipeline embolization device, flow re-direction endoluminal device and surpass flow diverters in the treatment of intracerebral aneurysms.

OBJECTIVES: The use of flow diversion for the treatment of intracranial aneurysms has gained broad acceptance. Three flow-diverting stents are approved by the Food and Drug Administration for use in the United States. We sought to compare the outcomes and safety profiles between the three devices at our institution. METHODS: A retrospective review of aneurysms treated with pipeline embolization device (PED), flow re-direction endoluminal device (FRED), and SURPASS was performed for aneurysms treated between 2018 and 2022 at our institution. RESULTS: The study cohort consisted of 142 patients. Precisely, 86 aneurysms were treated with a pipeline, 33 aneurysms were treated with FRED, and 23 aneurysms were treated with SURPASS. The 1-year complete occlusion rates were 59.4%, 60%, and 65%, respectively (0.91). Linear regression models found that only adjunctive coiling predicted aneurysm occlusion at 6 months (p = 0.02), but this effect was lost at 1 year and beyond. There was no significant difference in acute thrombotic or acute hemorrhagic complications between the three cohorts. There was a higher rate of delayed hemorrhagic complications in the SURPASS cohort (10%) compared to the PED (1.3%) and FRED (0%) cohorts (p = 0.04). There was also a higher rate of in-stent stenosis in the SURPASS cohort (20%) compared to the PED (5%) and FRED (3.1%) cohorts (p < 0.01). CONCLUSIONS: Treatment with PED, FRED, and SURPASS all resulted in similar complete occlusion rates at 6 months and 1 year. SURPASS was associated with higher in-stent stenosis as well as delayed hemorrhagic complications. Additional future studies evaluating the newest generation of flow-diverting stents with long-term follow-up will be necessary to make any definitive conclusions.

Drainage, Irrigation, and Fibrinolytic Therapy (DRIFT) for Adult Intraventricular Hemorrhage Associated with Primary Hypertensive Hemorrhages Using IRRAflow Self-Irrigating Catheter: A Report of Three Cases and Prior Historical Controls.

BACKGROUND: Spontaneous primary intracerebral hemorrhage (ICH) accounts for 10%-15% of strokes and is accompanied by ventricular involvement in 10%-30% of cases. Intraventricular hemorrhage (IVH) is a poor prognostic factor and the current treatment paradigm of external ventricular drainage requires frequent flushing and replacement. Given the documented high rate of failure standard EVD catheters, we sought to determine if the use of the IRRAflow system with the addition of alteplase would be beneficial in this patient population for the treatment of IVH associated with primary hypertensive ganglionic hemorrhages. METHODS: Three patients with ganglionic hemorrhages and IVH underwent treatment with the IRRAflow system at our institution from December 2022 to January 2023. A retrospective review was then performed of patients with primary hypertensive ganglionic hemorrhages and EVD placement at our institution from January 2021 to present day. RESULTS: Three patients underwent treatment with the IRRAflow system and continuous lavage of Tissue Plasminogen Activator (tPA). The IVH was efficiently cleared in all cases and the drains were removed within 8 days in all cases. No patients required replacement of the drain and there were no hemorrhagic complications noted. In our retrospective review, 28 patients were identified who underwent placement of a standard EVD for the treatment of primary hypertensive ganglionic hemorrhages. When patients who had early withdrawal of care were excluded, the average length of EVD treatment was 11.3 days and the EVD replacement rate was 24%. CONCLUSIONS: We demonstrate here that the use of the IRRAflow system for the treatment of primary hypertensive hemorrhages with IVH results in rapid clearance of the IVH without safety concerns. Compared to historical controls there was a decrease in EVD duration, EVD replacement and, ICU LOS.

Use of intravenous cangrelor in the treatment of ruptured and unruptured cerebral aneurysms: an updated single-center analysis and pooled analysis of current studies.

BACKGROUND: Intracranial stent placement for the treatment of cerebral aneurysms is increasingly utilized in both ruptured and unruptured scenarios. Intravenous (IV) cangrelor is a relatively new antiplatelet agent that was initially approved for coronary interventions. In addition to our institution, five other centers have published their results using IV cangrelor in neurointerventional procedures. This article combines the aneurysm treatment data from all prior studies to provide insight into the safety and efficacy of cangrelor for intracranial aneurysm treatment. METHODS: A prospectively maintained database was reviewed to identify all cases of IV cangrelor administration during aneurysm embolization. 20 additional patients were identified who had not been previously published. In addition, a literature search was performed to identify prior publications regarding cangrelor in neurointervention. The data from these were combined with our institutional results in a pooled-analysis. RESULTS: Overall, 85 patients who received IV cangrelor during aneurysm embolization were identified, including 46 ruptured and 39 unruptured cases. The asymptomatic and symptomatic intracranial hemorrhage rates were 4% (2/46) for ruptured cases and 2.6% (1/39) for unruptured cases. The rate of retroperitoneal hematoma and gastrointestinal bleeding was 0%. There were no incidents of intraprocedural thromboembolic complication or intraprocedural in-stent thrombosis in either cohort. One subject suffered an ischemic stroke at 24 hours secondary to in-stent thrombosis in a ruptured case. CONCLUSIONS: IV cangrelor during aneurysm embolization appears to be safe, with a symptomatic intracranial hemorrhage rate of 4% in ruptured cases and 2.6% in unruptured cases. More research is needed to determine the ideal dosing regimen.

Developing a fast-track discharge protocol for patients with cerebral aneurysms treated via neuroendovascular techniques.

INTRODUCTION: As we emerge from the current pandemic, hospitals, staff, and resources will need to continue to adjust to meet ongoing healthcare demands. Lessons learned during past shortages can be used to optimize peri-procedural protocols to safely improve the utilization of hospital resources. METHODS: Retrospective review of patients who underwent elective endovascular intracranial aneurysm treatment was performed. Multivariable logistic regression was used to identify factors associated with patients who were able to be discharged within 24 h of elective procedures. Rates of complications (particularly readmission) were determined. RESULTS: 330 patients underwent elective endovascular aneurysm treatment with 86 (26.1%) discharged within 24 h. Factors associated with earlier discharge included procedure years (2019-2021) and male sex. Patients were more likely to be discharged later (after 24 h) if they underwent stent-coil embolization or flow-diversion. There was no association between discharge timing and likelihood of readmission. DISCUSSION: Our review highlights the safety of earlier discharge and allowed us to prepare a fast-track protocol for same-day discharge in these patients. This protocol will be studied prospectively in the next phase of this study. As we gain more comfort with emerging, minimally invasive endovascular therapies, we hope to safely achieve same-day discharge on a protocolized and routine basis, reducing the demand of elective aneurysm treatments on our healthcare system. CONCLUSION: We retrospectively demonstrate that early discharge following elective aneurysm treatment is safe in our cohort and provide a fast-track pathway based on these findings for other centers developing similar protocols.

Comparison of hydrogel coils versus bare platinum coils for the treatment of anterior communicating artery aneurysms.

INTRODUCTION: While endovascular coiling has been shown to be a safe treatment option for intracranial aneurysms, there remains concern regarding increased recurrence and retreatment rates. Preliminary studies evaluating hydrogel coated coils have demonstrated decreased recurrence rates compared to bare metal coils. METHODS: A retrospective chart review was done on all patients with anterior communicating artery aneurysms (ACoAAs) treated with endovascular coiling between 2014 and 2018. Treatment groups were divided into hydrogel coated coils or bare metal coils. Patients were categorized into the hydrogel group when ≥ 70% of the coil length was hydrogel coated. RESULTS: Eighty-four ACoAAs were treated with coil embolization between 2014 and 2018. Postoperative imaging was available for 68 patients. Twenty-six patients were categorized into the hydrogel treatment group. Aneurysm recurrence was seen in 7.7% (2/26) of patients treated with hydrogel coated coils compared to 33.3% (14/42) of those treated with bare metal coils (P = 0.03). Subanalysis of patients with ruptured aneurysms revealed decreased recurrence rates in patients treated with hydrogel coated coils at 5.9% (1/17) compared to patients treated with bare metal coils at 39.4% (13/33) (P = 0.01). CONCLUSIONS: Hydrogel-coated coils may reduce recurrence rates in the treatment of both ruptured and unruptured ACoAAs.

Characterization of antiplatelet response to low-dose cangrelor utilizing platelet function testing in neuroendovascular patients.

STUDY OBJECTIVES: The optimal antiplatelet therapy for emergent neuroendovascular stenting is uncertain. Cangrelor is an intravenous P2Y12 inhibitor that is an attractive option due its favorable pharmacokinetic profile and ease of measurability but optimal dosing remains unclear. The primary objective of this study is to characterize the dose response of low dose cangrelor (<2 mcg/kg/min) with the utilization of platelet function testing (PFT). DESIGN: A retrospective review of all patients treated with cangrelor for either procedural stenting or bridging was conducted between January 1st, 2019 and October 31st, 2020. Seventy-two patients met inclusion criteria. An in-depth analysis of dose response to low dose cangrelor based on PFT was performed. PATIENTS: Neuroendovascular patients treated with cangrelor. SETTING: Albany Medical Center Hospital. INTERVENTION AND MAIN RESULTS: Patients who underwent procedural stenting were given a bolus of 5 mcg/kg and an initial infusion rate of either 0.75 mcg/kg/min or 1 mcg/kg/min. Patients who were bridged with cangrelor were administered an initial infusion rate of 0.75 mcg/kg/min or 1 mcg/kg/min. Twelve patient's doses were titrated to achieve a platelet reactivity unit (PRU) between 50-150; three patient's doses were titrated multiple times. Based on initial PFT results, utilizing the 1 mcg/kg/min maintenance dose resulted in more patients being in the acceptable (10-180) and desired (50-150) PRU range than the 0.75 mcg/kg/min dose (47% vs 56% and 70% vs 80%, respectively). Final recorded PRU results showed that 64% of patients had PRUs in the optimal range (50-150) and 88% of patients had PRUs in the desire range (10-180). CONCLUSIONS: Utilizing low doses of cangrelor with platelet function testing is an option during emergent neuroendovascular stenting and bridging. Cangrelor demonstrates significant variability in response at low doses and exhibits a dose response relationship when PFT is utilized.

Delayed hypersensitivity reaction to a dural repair substitute.

BACKGROUND: Modern neurosurgeons commonly rely on dural grafts to aid in obtaining watertight closures when the native dura itself cannot be approximated. CASE PRESENTATION: We present a patient who developed a symptomatic, delayed hypersensitivity reaction to a cellulose-based synthetic dural graft, which resolved after reoperation and removal of the graft. DISCUSSION: Dural grafts are a safe and common implant utilized in neurosurgery. Nevertheless, as with all implanted material, there is a chance for symptomatic immune reactions to occur. CONCLUSION: This type of response is exceedingly uncommon, but recognition of this rare presentation may help other providers recognize it in the future.

The Role of Gender in Neurosurgical Residency Applicants' Letters of Recommendation.

BACKGROUND: Letters of recommendation (LORs) are one of the most important components of the neurosurgical residency application. Studies in other fields and surgical subspecialties have found gender bias. OBJECTIVE: To determine whether neurosurgical LORs contain significant linguistic gendered differences. METHODS: We performed a retrospective review and linguistic analysis of all LORs submitted on behalf of applicants offered an interview invitation to a single neurosurgical residency program at an academic medical center between 2015-2016 and 2018-2019. RESULTS: A total of 599 letters from 156 applicants (120 males and 36 females) were included. Background demographics, including United States Medical Licensing Examination (USMLE) Step 1 score and publications, were not significantly different between applicants. Male faculty authored 93% of all letters. Female faculty were more likely to write letters for female applicants than male applicants (12.1% vs 5.5%, P < .001). Letters for women were significantly longer (334 words vs 277 words, P < .001). Overall, 1754 agentic terms and 854 communal terms were coded. Letters for men contained significantly fewer agentic terms (10.7 vs 13.1, per applicant, P < .01) and communal terms (5.2 vs 6.4, P < .034). This difference, however, is nonsignificant when word count was used as a covariate. Female applicants were more significantly likely to be labeled "Outstanding" (2.4 vs 1.6 mentions per applicant). CONCLUSION: Overall, there are more similarities than differences between genders in LORs for neurosurgical applicants. This finding is at odds with what has previously been reported in most other surgical specialties.

Use of intravenous cangrelor and stenting in acute ischemic stroke interventions: a new single center analysis and pooled-analysis of current studies.

INTRODUCTION: Emergent stenting of both extra- and intracranial occlusions during acute ischemic stroke procedures is complicated by the need for immediate platelet inhibition to prevent thromboembolic complications. IV cangrelor is a relatively new antiplatelet that was initially approved for coronary interventions. Five prior case series have been published evaluating the results of IV cangrelor in neurointerventional procedures. We sought to combine the data from all prior studies and analyze only ischemic stroke interventions. METHODS: A prospectively maintained database was reviewed to identify all cases of IV cangrelor administration during acute ischemic stroke intervention. Nine additional patients were identified who have not been previously published. In addition, a literature search was performed to identify five prior publications of cangrelor in neurointervention. The data from these was combined with our institution in a pooled-analysis. RESULTS: Overall, 129 patients who received IV cangrelor during an acute ischemic stroke intervention were identified. The asymptomatic intracranial hemorrhage rate was 12.6%(11/87). The symptomatic intracranial hemorrhage rate was 6.2% (8/129). The rate of retroperitoneal hematoma and gastrointestinal bleeding were also low (1.5% and 0.8%, 2/129 and 1/129). There was one case of intraprocedural thromboembolic complication (0.8%) and no cases of intraprocedural in-stent thrombosis(0%). CONCLUSIONS: IV cangrelor during acute ischemic stroke intervention appears to be safe, with a symptomatic intracranial hemorrhage rate of 6.2%. More research is needed to determine the ideal dosing regimen.

Outpatient management of chronic expanding subdural hematomas with endovascular embolization to minimize inpatient admissions during the COVID-19 viral pandemic.

Chronic subdural hematomas are complex collections that usually form after a trauma, particularly in elderly patients. This vulnerable population is at increased risk given the current viral pandemic. We share our experience in managing minimally symptomatic, enlarging subdural collections via middle meningeal embolization through the outpatient setting. This approach minimizes inpatient hospitalizations in hopes or reducing nosocomial spread (e.g., of COVID-19).

Neurosurgical management of vascular compression presenting as visual symptoms secondary to elongated styloid processes (Eagle syndrome).

BACKGROUND: Eagle syndrome (ES) was first described in 1937, to characterize elongation of the styloid process. It is rarely encountered by neurosurgeons but does present the potential for vascular sequelae and neurological complications. DEMONSTRATIVE CASES: We discuss three patients with uncommon presentations of neurovascular compromise with uncommon symptomatology, secondary to ES. Their management ranged from retrospective diagnoses following self-limited events, antiplatelet therapy, and endovascular and surgical interventions. DISCUSSION: While traumatic fractures, chiropractic manipulation, and history of prior neck surgery have been implicated as the etiologies for ES, congenital cases are common. The styloid process intimately interplays with adjacent neurovascular and nervous structures; its elongation can cause symptoms in 10% of patients. CONCLUSION: Awareness of this potentially dangerous but rare disease - more commonly seen by our otolaryngology colleagues - may help reduce diagnostic delays when an elongated styloid process is the cause, as surgery may be required.

Cangrelor dose titration using platelet function testing during cerebrovascular stent placement.

BACKGROUND: Optimal antiplatelet inhibition is vital during cerebrovascular stenting procedures, yet no standardized recommendation exists for antithrombotic therapy in these scenarios. Cangrelor is an intravenous P2Y12 inhibitor with a favorable pharmacokinetic profile for use during neuroendovascular stenting. METHODS: A retrospective review of all neuroendovascular patients who underwent stenting between 1 January 2019 and 22 March 2020 and were treated with cangrelor was conducted. Thirty-seven patients met inclusion criteria. RESULTS: All patients were administered a bolus of 5 mcg/kg of cangrelor followed by a maintenance infusion. Antiplatelet effects of cangrelor were monitored using platelet reactivity units (PRU). Based on the initial PRU, seven patients' doses were adjusted with subsequent PRUs in or near the goal range of 50-150. One patient experienced an acute intraprocedural occlusion likely related to a subtherapeutic PRU which subsequently resolved with cangrelor dose adjustment and intra-arterial tirofiban administration, and one patient experienced a post-procedure stent occlusion which required a thrombectomy and intra-arterial tirofiban administration. No hemorrhagic complications occurred. DISCUSSION: Cangrelor utilization during neuroendovascular stenting with maintenance doses of <2 mcg/kg/min with dose adjustments based on platelet function testing has not been previously described. Cangrelor presents many advantages compared to standard therapy in patients undergoing stent placement related to its pharmacokinetic profile, rapid onset of action, ease of transition to oral P2Y12 antiplatelet agents, and measurability. CONCLUSION: Cangrelor is a promising alternative to currently available therapies, especially in patients with a high hemorrhagic risk.

Postoperative fever workup in pediatric neurosurgery patients.

OBJECTIVE: Fevers are common in the postoperative period, and adult data indicate that workup for an isolated fever is not warranted in the first 4 postoperative days (PODs). Pediatric literature on the subject similarly questions the value of further investigation during the first 2 PODs. The purpose of this study was to determine the incidence of acute fever in the postoperative pediatric neurosurgical population, as well as to assess the utility of performing further workup on these patients. METHODS: A single-institution retrospective study was performed to assess pediatric neurosurgery patients following surgical intervention for the diagnoses of craniosynostosis, Chiari malformation, and brain tumors from 2009 to 2018. Fevers were identified during the first 4 PODs and were defined as a temperature ≥ 38.0°C. The patient charts were queried for urinalysis and urine culture (UA/Ucx), chest radiographs, blood cultures, CSF culture, respiratory viral panel, white blood cell (WBC) count, transfusion history, development of wound infection, and placement of external ventricular drains (EVDs) or lumbar drains. Thirty-day postoperative microbiology results and readmissions were reviewed. Descriptive statistics were performed using logistic regression analysis. RESULTS: Two hundred thirty-five patients were evaluated, and 61% had developed fevers within the first 4 PODs. Thirty-eight (26.6%) of the 143 febrile patients underwent further workup, and those with high fevers (> 39.0°C) were more likely to undergo further evaluation, which most commonly included UA/Ucx (21.7%). Approximately 1% (2/235) of the patients were found to have an infection during the first 4 days, and 8 additional patients developed a complication following the initial 4 days and within the first 30 PODs. The development of infectious complications within the first 4 PODs did not correlate with acute postoperative fevers (p = 0.997), nor did the development of complications within the 30 days following surgery (p = 0.776); however, multiple days of acute postoperative fevers (p = 0.034) and the presence of an EVD (p = 0.001) were associated with the development of infectious complications within 30 days. Acute postoperative fevers were associated with EVD placement (p = 0.038), as well as blood product transfusions and an increased WBC count (p < 0.001). CONCLUSIONS: Isolated fevers manifesting within the first 4 PODs are rarely associated with an infectious etiology. Additional factors should be taken into consideration when deciding to pursue further investigation.

Selection of Neurological Surgery Applicants and the Value of Standardized Letters of Evaluation: A Survey of United States Program Directors.

BACKGROUND: The letter of recommendation (LOR) represents a nonstandardized way to evaluate residency candidates. The goal of this project was to assess the current components of the Electronic Residency Application Service application and to determine and develop support for a standardized letter of evaluation (SLOE) in the resident selection process. METHODS: A 16-question survey was sent to US neurosurgery program directors. In addition to demographic information, respondents were asked to rank 7 aspects of the current application (1-7), evaluate the inclusion of specific standardized questions about applicants (yes or no), note their agreement with statements about LORs (on a 5-point Likert scale), and provide any additional comments. RESULTS: Fifty-three of 113 program directors (47%) completed the survey. The interview (average rank, 2.0 ± 1.4), United States Medical Licensing Exam step 1 score (2.86 ± 1.4), and LOR (2.96 ± 1.5) were ranked as the most important aspects of the application. Agreement was high for items regarding the utility of the current LOR (51%-78% agreement). Almost two-thirds (65%) of program directors agreed that implementing a standardized LOR would improve the resident selection process. Inclusion of questions regarding applicants' work ethic, teamwork, communication, professionalism, and initiative were strongly supported (>80% in favor), whereas including a question on theoretical rank position was mixed (54%). CONCLUSIONS: Most neurosurgical program directors agree that increasing the objectivity of the application would be beneficial, including the addition of standardized questions. However, there is only moderate interest in implementing an SLOE.