Evaluating the Impact of the COVID-19 Pandemic on Late-Canceled and No-Show Appointments at the Department of Neurological Surgery.

The coronavirus disease 2019 (COVID-19) pandemic resulted in unprecedented restrictions on the general public and disturbances to the routines of hospitals worldwide. These restrictions are now being relaxed as the number of vaccinated individuals increases and as the rates of incidence and prevalence decrease; however, they left a lasting impact on healthcare systems that is still being felt today. This retrospective study evaluated the total number of canceled or missed outpatient clinic appointments in a Neurological Surgery department before and after peak COVID-19 restrictions and attempted to assess the impact of these disruptions on neurosurgical clinical attendance. We also attempted to compare our data with the data from another surgical subspecialty department. We evaluated 32,558 scheduled appointments at the Loyola University Medical Center Department of Neurological Surgery, as well as 139,435 scheduled appointments with the Department of Otolaryngology. Appointments before April 2020 were defined as pre-COVID, while appointments during or after April 2020 were defined as post-COVID. Here, we compare no-show and non-attendance rates (no-shows plus late-canceled appointments) within the respective time range. Overall, we observed that before COVID-19 restrictions were put into place, there was an 8.9% no-show rate and a 17.4% non-attendance rate for the Department of Neurological Surgery. After COVID restrictions were implemented, these increased to 10.9% and 18.3%, respectively. Greater no-show and cancellation rates (9.8% in the post-COVID era vs 8.0% in the pre-COVID era) were associated with varying socioeconomic and racial demographics. African-American patients (2.56 times higher), new-visit patients (1.67 times higher), and those with Medicaid/Medicare insurance policies (1.48 times higher) were at the highest risk of no-show in the post-COVID era compared to the pre-COVID era.

A Predictive Model for Intraoperative CSF Leak During Endonasal Pituitary Adenoma Resection Using a Convolutional Neural Network.

INTRODUCTION: Cerebrospinal fluid (CSF) leak during endoscopic endonasal transsphenoidal surgery (EETS) can lead to postoperative complications. The clinical and anatomic risk factors of intraoperative CSF leak are not well defined. We applied a 2D convolutional neural network (CNN) machine learning (ML) model to identify risk factors from preoperative magnetic resonance imaging (MRI). METHODS: All adults who underwent EETS at our institution from January 2007 to March 2023 who had accessible preoperative stereotactic MRIs were included. A retrospective classic statistical analysis was performed to identify demographic, clinical, and anatomic risk factors of intraoperative CSF leak. Stereotactic T2 brain MRIs were utilized to train and test a 2D CNN model. RESULTS: 220 patients were included, 81 (36.8%) of whom experienced intraoperative CSF leak. Amongst all preoperative variables, visual disturbance was the only statistically significant identified risk factor (p-value:0.008). The trained 2D CNN model predicted CSF leak with 92% accuracy and area under receiver operative characteristic curve of 0.90 (sensitivity of 86% and specificity of 93%). Class activation mapping (CAM) of this model revealed that anatomic regions of CSF flow were most important in predicting CSF leak. CONCLUSION: Further review of the CAM gradients revealed regions of the diaphragma sellae, clinoids, temporal horns, and the optic nerves to have anatomical correlation to the risks of intraoperative CSF leak. Additonally, visual disturbances from anatomic compression of the optic chiasm was the only identified clinical risk factor. We believe that our 2D CNN model can help improve a treating team's anticipation of and preparation for an intraoperative leak.

A systematic review and meta-analysis of major blood protein biomarkers that predict unfavorable outcomes in severe traumatic brain injury.

INTRODUCTION: Severe traumatic brain injury (TBI) presentation and late clinical outcomes are usually evaluated by the Glasgow Outcome Scale-Extended (GOS-E), which lacks strong prognostic predictability. Several blood biomarkers have been linked to TBI, such as Tau, GFAP, UCH-L1, S-100B, and NSE. Clinical values of TBI biomarkers have yet to be evaluated in a focused multi-study meta-analysis. We reviewed relevant articles evaluating potential relationships between TBI biomarkers and both early and 6-month outcomes. METHODS: All PubMed article publications from January 2000 to November 2023 with the search criteria "Protein Biomarker" AND "Traumatic Brain Injury" were included. Amongst all comparative studies, the sensitivity means and range values of biomarkers in predicting CT Rotterdam scores, ICU admission in the early period, or predicting GOS-E < 4 at the 6-month period were calculated from confusion matrices. Sensitivity values were modeled for each biomarker across studies and compared statistically for heterogeneity and differences. RESULTS: From the 65 articles that met the criteria, 13 were included in this study. Six articles involved early-period TBI outcomes and seven involved 6-month outcomes. In the early period TBI outcomes, GFAP had a superior sensitivity to UCH-L1 and S-100B, and similar sensitivity to the CT Rotterdam score. In the 6-month period TBI outcomes, total Tau and NSE both had significant interstudy heterogeneity, making them inferior to GFAP, phosphorylated Tau, UCH-L1, and S-100B, all four of which had similar sensitivities at 75 %. This sensitivity range at 6-month outcomes was still relatively inferior to the CT Rotterdam score. Total Tau did not show any prognostic advantage at six months with GOS-E < 4, and phosphorylated Tau was similar in its sensitivity to other biomarkers such as GFAP and UCH-L1 and still inferior to the CT Rotterdam score. CONCLUSION: This data suggests that TBI protein biomarkers do not possess better prognostic value with regards to outcomes.

Evaluation of Retrospective Patient Preference on Extent of Resection of Nonfunctioning Pituitary Adenomas.

BACKGROUND: Neurosurgeons treat nonfunctioning pituitary adenomas by surgical resection. Based on the adherence of the tumor to the normal pituitary gland, operative risks may include hormone replacement therapy for postoperative hypopituitarism with gross total resection that injures the gland or recurrent tumor with subtotal resection and purposeful avoidance of gland manipulation. None of the patients presented in this article had a preoperative preference regarding extent of resection. This study aimed to evaluate postoperative patient preferences regarding extent of resection. METHODS: Adult patients who underwent resection of adenomas between 2015 and 2023 were retrospectively reviewed and surveyed. After surgery, participating patients were asked for their preference regarding 100% tumor resection with lifelong daily hormone replacement therapy versus 90% tumor resection with a chance of recurrence in the hypothetical situation where the neurosurgeon encounters tumor adherent to the normal gland. RESULTS: Of the 73 patients included, 54 (74.0%) responded to the survey, with the majority (36 [66.7%]) preferring 90% resection with the chance of tumor recurrence. Tumor recurrence (odds ratio 2.3, 95% confidence interval 2.1-2.5, P = 0.03) and steroid avoidance (odds ratio 2.2, 95% confidence interval 2.0-2.4, P = 0.04) were the 2 variables that were significant predictors of patient preference in multivariate regression analysis. CONCLUSIONS: Although patients may not have the preoperative insight or experience to have a strong conviction regarding the extent of adenoma resection, the consequences following surgery clearly influence their preference. Most patients in our study, including patients with gross total resection and especially patients who experienced side effects of steroid therapy, preferred subtotal resection with the chance of tumor recurrence over hormone replacement therapy.

Risk Factors Associated with Spinal Cord Ischemia During Aortic Aneurysm Repair.

BACKGROUND: The risk of spinal cord ischemia (SCI) with aortic aneurysm repair can cause significant neurological morbidity. Prevention of SCI is critical. We sought to identify risk factors that predispose to SCI that may guide strategies to mitigate the occurrence of SCI during and following these procedures. METHODS: This study includes all adults who underwent atraumatic, unruptured, thoracic, and suprarenal aortic aneurysm repairs (endovascular or open) at our institution over 11 years (2010-2020). Our database included patient demographics, aneurysm anatomic features, and operative characteristics and an extreme gradient boost (XGB) machine method was used to develop a predictive model for SCI. The model was trained on an 80% randomly stratified cohort of the data and tested on the remaining 20% testing cohort. Shapley values were used to determine the most important predictive factors of SCI and decision trees were used to identify risk factor threshold values and highest risk factor combinations. RESULTS: Information was collected for 174 adult patients undergoing thoracic and suprarenal aortic repair from 2010 to 2020. Fifty eight percent of the patients were male. Ninety seven (55.7%) patients had open aortic repair and 87 (44.3%) had endovascular repair. Twenty seven (15%) of all patients had major complications and were considered to have SCI. The XGB model converged over the training cohort with a testing cohort accuracy of 0.841 [Sensitivity = 75%, Specificity = 68%] and area under the curve of receiver operating characteristic of 0.774. The XGB model identified older age (> 65 years), history of neurologic disease, hyperlipidemia, diabetes, coronary artery disease, heart failure, poor renal function, < 6 months since last aortic repair, chronic anticoagulant use, preoperational anemia (Hemoglobin < 9), thrombocytopenia (platelet < 90,000), coagulopathy (prothrombin time > 15s and activated partial thromboplastin time > 40s), hypotension (mean arterial pressure < 70 mm Hg), longer operations (> 100 min), aneurysms longer than 5 cm, and anatomic location of aneurysm caudal to T-11 as risk factors for SCI in all types of aortic repair. Diabetic and heart failure patients undergoing longer operations (> 100 min) with thrombocytopenia or aneurysms longer than 5 cm were at the highest risk. CONCLUSIONS: The XGB model accurately identified risk factors of SCI with aortic aneurysm repair that may guide patient selection, timing of surgery, and strategies to minimize the risk of SCI.

Concomitant Orthopedic Injury is the Strongest Predictor of Amputation in Extremity Vascular Trauma.

BACKGROUND: Although the risk of extremity amputation related to an isolated vascular injury is low, it increases significantly with concomitant orthopedic injury. Our study aims to evaluate and quantify the impact of risk factors associated with trauma-related extremity amputation in patients with vascular injury. We sought to determine whether there are other potential predictors of amputation. METHODS: A retrospective review of patients with extremity vascular injury presenting to a single level 1 academic trauma center between January 1, 2007, and December 31, 2018, was performed. All patients diagnosed with major vascular injury to the upper or lower extremity were included. Data on patient demographics, medical comorbidities, anatomic location of vascular injury, and the presence of soft tissue or orthopedic injury were collected. The main outcome measure was major amputation of the affected extremity. Major amputation included below-the-knee amputation, above-the-knee amputation, as well as any amputation of the upper extremity at or proximal to the wrist. RESULTS: We identified 250 extremities with major vascular injury in 234 patients. Of these, 216 (86.4%) were male and 34 (13.6%) female. The mean age was 32.2 years (range 18-79 years) and mean follow-up was 6.9 (standard deviation: 3.3) years. Just over half of injuries, 130 (52.0%) involved the lower extremity. Forty extremities (29 lower and 11 upper), or 16.0%, of total injured extremities, required major amputation during the follow-up period. Concomitant orthopedic injury was present in 106 of 250 (42%) injured extremities. Using univariable logistic regression models, variables with a significant association with major amputation included older age, higher body mass index, blunt mechanism of injury, concomitant orthopedic injury, soft tissue injury, and nerve injury, and the need for fasciotomy (P < 0.05). In multivariable analyses, blunt mechanism of injury (odds ratio [OR] (confidence ratio {CI}): 6.51 (2.29, 18.46), P < 0.001) and concomitant orthopedic injury (OR [CI]: 7.23 [2.22, 23.55], P = 0.001) remained significant predictors of amputation. CONCLUSIONS: Concomitant orthopedic injury and blunt mechanism in the setting of vascular injury are associated with a higher likelihood of amputation in patients with extremity vascular injury. Further development of a vascular extremity injury protocol may be needed to enhance limb salvage. Findings may guide patient discussion regarding limb-salvage decision-making.

Comparison of transarterial n-BCA and Onyx embolization of brain arteriovenous malformations: A single-center 18-year retrospective analysis.

OBJECTIVE: Brain arteriovenous malformations (AVM) are commonly treated with endovascular embolization. Due to the rapid evolution of endovascular technology and lack of consistent practice guidelines regarding AVM embolization, further study of AVM embolization outcomes is warranted. METHODS: We conducted a retrospective review of AVMs embolized at a single center from 2002-2019. Patient demographics, AVM characteristics, intention of embolization, and angiographic and clinical outcome after embolization were recorded. We compared the embolization results of those treated with n-butyl cyanoacrylate (n-BCA) and Onyx. RESULTS: Over an 18-year period at our institution, 30 (33%) of 92 AVMs were treated with embolization. n-BCA was used in 12 cases and Onyx in 18 cases. Eighty-seven pedicles were embolized over 47 embolization sessions. Fifty percent of AVMs treated with n-BCA underwent more than one embolization session compared to 22% when Onyx was used. The median total percent volume reduction in the n-BCA AVMs was 52% compared to 51% in Onyx AVMs. There were 2 periprocedural complications in the n-BCA cohort and none in the Onyx cohort. CONCLUSIONS: In this small retrospective series, Onyx and n-BCA achieved similar occlusion results, although n-BCA required more sessions and pedicles embolized to do so.

Angioarchitectural features amongst patients with unruptured brain arteriovenous malformations presenting with headache: findings from a single center retrospective review of 76 patients.

BACKGROUND: Brain arteriovenous malformations (AVMs) consist of abnormal connections between arteries and veins via an interposing nidus. While hemorrhage is the most common presentation, unruptured AVMs can present with headaches, seizures, neurological deficits, or be found incidentally. It remains unclear as to what AVM characteristics contribute to pain generation amongst unruptured AVM patients with headaches. METHODS: To assess this relationship, the current study evaluates angiographic and clinical features amongst patients with unruptured brain AVMs presenting with headache. Loyola University Medical Center medical records were queried for diagnostic codes corresponding to AVMs. In patients with unruptured AVMs, we analyzed the correlation between the presenting symptom of headache and various demographic and angiographic features. RESULTS: Of the 144 AVMs treated at our institution between 1980 and 2017, 76 were unruptured and had sufficient clinical data available. Twenty-three presented with headaches, while 53 patients had other presenting symptoms. Patients presenting with headache were less likely to have venous stenosis compared to those with a non-headache presentation (13 % vs. 36 %, p = 0.044). CONCLUSIONS: Our study suggests that the absence of venous stenosis may contribute to headache symptomatology. This serves as a basis for further study of correlations between AVM angioarchitecture and symptomatology to direct headache management in AVM patients.

Lumbar Drains for Vascular Procedures: An Institutional Protocol Review and Guidelines.

BACKGROUND: Aortic disease requiring open or endovascular repair may result in spinal cord injury in approximately 2%-10% of patients. Cerebrospinal fluid diversion using lumbar drains (LDs) has been validated as a protective measure to mitigate this complication. METHODS: This single-institution retrospective study analyzed the implementation of a standardized protocol and subsequent educational intervention for LDs for aortic vascular procedures over a 4-year period. RESULTS: In 2016-2019, 45 patients had LDs placed for open or endovascular procedures; group 1 included 19 patients with LDs placed before protocol implementation, and group 2 included 26 patients with LDs placed as per the institutional protocol. Demographics and procedural details in both groups were similar. However, there was a significant difference in the number of patients who had emergent versus planned placement of the LD (group 1, 89.5%; group 2, 50%; P < 0.01), volume of cerebrospinal fluid drained (group 1, 453 mL; group 2, 197 mL; P < 0.01), and compliance with 10 mL/hour drainage recommendation (group 1, 68.4%; group 2, 100%; P < 0.01). In group 1, 5 (31.6%) patients experienced neurological complications compared with only 1 (3.8%) in group 2. LD-related complications occurred 3 patients (15.8%) in group 1, whereas none occurred in group 2. Survey results suggested increased health care worker protocol familiarity with educational interventions. CONCLUSIONS: Implementation of an institutional protocol for LDs for open or endovascular procedures is feasible and beneficial. Educational modules improve familiarity among all health care providers, which can improve patient care and complication avoidance.

Acute thoracic disc heralded by change in spinal cord stimulation pattern: illustrative case.

BACKGROUND: Spinal cord stimulation (SCS) uses unique electric stimulation parameters to selectively treat specific regions of chronic or refractory back pain. Changing these parameters can lead to spreading paresthesia and/or pain beyond the desired region. OBSERVATIONS: A patient with a history of stable, successful SCS treatment presented with acute development of paresthesias that were relieved by reduction of stimulation parameters. The patient required paradoxically lower SCS settings for control of chronic back pain. This presentation prompted further investigation, which revealed a new disc protrusion and cord compression at the level of the paddle lead. LESSONS: In patients with SCS, a new onset of back pain accompanied by acute paresthesia that is reversible by reducing the SCS amplitude warrants investigation for new spine pathology.

Trends, Cost, and Mortality From Sepsis After Trauma in the United States: An Evaluation of the National Inpatient Sample of Hospitalizations, 2012-2016.

OBJECTIVES: Identification and outcomes in patients with sepsis have improved over the years, but little data are available in patients with trauma who develop sepsis. We aimed to examine the cost and epidemiology of sepsis in patients hospitalized after trauma. DESIGN: Retrospective cohort study. PATIENTS: National Inpatient Sample. INTERVENTIONS: Sepsis was identified between 2012 and 2016 using implicit and explicit International Classification of Diseases, Ninth and Tenth Revision codes. Analyses were stratified by injury severity score greater than or equal to 15. Annual trends were modeled using generalized linear models. Survey-adjusted logistic regression was used to compare the odds for in-hospital mortality, and the average marginal effects were calculated to compare the cost of hospitalization with and without sepsis. MEASUREMENTS AND MAIN RESULTS: There were 320,450 (SE = 3,642) traumatic injury discharges from U.S. hospitals with sepsis between 2012 and 2016, representing 6.0% (95% CI, 5.9-6.0%) of the total trauma population (n = 5,329,714; SE = 47,447). In-hospital mortality associated with sepsis after trauma did not change over the study period (p > 0.40). In adjusted analysis, severe (injury severity score ≥ 15) and nonsevere injured septic patients had an odds ratio of 1.39 (95% CI, 1.31-1.47) and 4.32 (95% CI, 4.06-4.59) for in-hospital mortality, respectively. The adjusted marginal cost for sepsis compared with nonsepsis was $16,646 (95% CI, $16,294-$16,997), and it was greater than the marginal cost for severe injury compared with nonsevere injury $8,851 (95% CI, $8,366-$8,796). CONCLUSIONS: While national trends for sepsis mortality have improved over the years, our analysis of National Inpatient Sample did not support this trend in the trauma population. The odds risk for death after sepsis and the cost of care remained high regardless of severity of injury. More rigor is needed in tracking sepsis after trauma and evaluating the effectiveness of hospital mandates and policies to improve sepsis care in patients after trauma.

Sequential conditioning-stimulation reveals distinct gene- and stimulus-specific effects of Type I and II IFN on human macrophage functions.

Macrophages orchestrate immune responses by sensing and responding to pathogen-associated molecules. These responses are modulated by prior conditioning with cytokines such as interferons (IFNs). Type I and II IFN have opposing functions in many biological scenarios, yet macrophages directly stimulated with Type I or II IFN activate highly overlapping gene expression programs. We hypothesized that a sequential conditioning-stimulation approach would reveal with greater specificity the differential effects of Type I and II IFN on human macrophages. By first conditioning with IFN then stimulating with toll-like receptor ligands and cytokines, followed by genome-wide RNA-seq analysis, we identified 713 genes whose expression was unaffected by IFN alone but showed potentiated or diminished responses to a stimulus after conditioning. For example, responses to the cytokine TNF were restricted by Type II IFN conditioning but potentiated by Type I IFN conditioning. We observed that the effects of IFN were not uniformly pro- or anti-inflammatory, but highly gene-specific and stimulus-specific. By assessing expression levels of key signal transducers and characterizing chromatin accessibility by ATAC-seq, we identify the likely molecular mechanisms underlying Type I and Type II-specific effects, distinguishing between modulation of cytoplasmic signaling networks and the nuclear epigenome that synergistically regulate macrophage immune responses.