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Nevin Manimala Statistics

Postoperative outcomes and the association with overlap before or after the critical step of lumbar fusion

J Neurosurg Spine. 2021 Oct 1:1-10. doi: 10.3171/2021.5.SPINE202105. Online ahead of print.

ABSTRACT

OBJECTIVE: This study assesses how degree of overlap, either before or after the critical operative portion, affects lumbar fusion outcomes.

METHODS: The authors retrospectively studied 3799 consecutive patients undergoing single-level, posterior-only lumbar fusion over 6 years (2013-2019) at a university health system. Outcomes recorded within 30-90 and 0-90 postoperative days included emergency department (ED) visit, readmission, reoperation, overall morbidity, and mortality. Furthermore, morbidity and mortality were recorded for the duration of follow-up. The amount of overlap that occurred before or after the critical portion of surgery was calculated as a percentage of total beginning or end operative time. Subsequent to initial whole-population analysis, coarsened exact-matched cohorts of patients were created with the least and most amounts of either beginning or end overlap. Univariate analysis was performed on both beginning and end overlap exact-matched cohorts, with significance set at p < 0.05.

RESULTS: Equivalent outcomes were observed when comparing exact-matched patients. Among the whole population, the degree of beginning overlap was correlated with reduced ED visits within 30-90 and 0-90 days (p = 0.007, p = 0.009; respectively), and less 0-90 day morbidity (p = 0.037). Degree of end overlap was correlated with fewer 30-90 day ED visits (p = 0.015). When comparing only patients with overlap, degree of beginning overlap was correlated with fewer 0-90 day reoperations (p = 0.022), and no outcomes were correlated with degree of end overlap.

CONCLUSIONS: The degree of overlap before or after the critical step of surgery does not lead to worse outcomes after lumbar fusion.

PMID:34598156 | DOI:10.3171/2021.5.SPINE202105

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Nevin Manimala Statistics

Depth resolution in multifocus laser speckle contrast imaging

Opt Lett. 2021 Oct 1;46(19):5059-5062. doi: 10.1364/OL.436334.

ABSTRACT

Laser speckle contrast imaging (LSCI) can be used to evaluate blood flow based on spatial or temporal speckle statistics, but its accuracy is undermined by out-of-focus image blur. In this Letter, we show how the fraction of dynamic versus static light scattering is dependent on focus, and describe a deconvolution strategy to correct for out-of-focus blur. With the aid of a z-splitter, which enables instantaneous multifocus imaging, we demonstrate depth-resolved LSCI that can robustly extract multi-plane structural and flow-speed information simultaneously. This method is applied to in vivo imaging of blood vessels in a mouse cortex and provides improved estimates of blood flow speed throughout a depth range of 300µm.

PMID:34598268 | DOI:10.1364/OL.436334

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Nevin Manimala Statistics

Long-term health-related quality of life and neurocognitive functioning after treatment in skull base meningioma patients

J Neurosurg. 2021 Oct 1:1-13. doi: 10.3171/2021.4.JNS203891. Online ahead of print.

ABSTRACT

OBJECTIVE: Patients with skull base meningioma (SBM) often require complex surgery around critical neurovascular structures, placing them at high risk of poor health-related quality of life (HRQOL) and possibly neurocognitive dysfunction. As the survival of meningioma patients is near normal, long-term neurocognitive and HRQOL outcomes are important to evaluate, including evaluation of the impact of specific tumor location and treatment modalities on these outcomes.

METHODS: In this multicenter cross-sectional study including patients 5 years or more after their last tumor intervention, Short-Form Health Survey (SF-36) and European Organisation for Research and Treatment of Cancer (EORTC) QLQ-BN20 questionnaires were used to assess generic and disease-specific HRQOL. Neurocognitive functioning was assessed with standardized neuropsychological assessment. SBM patient assessments were compared with those of 1) informal caregivers of SBM patients who served as controls and 2) convexity meningioma patients. In addition, the authors compared anterior/middle SBM patients with posterior SBM patients and anterior/middle and posterior SBM patients separately with controls. Multivariable and propensity score regression analyses were performed to correct for possible confounders.

RESULTS: Patients with SBM (n = 89) with a median follow-up of 9 years after the last intervention did not significantly differ from controls (n = 65) or convexity meningioma patients (n = 84) on generic HRQOL assessment. Statistically significantly but not clinically relevantly better disease-specific HRQOL was found for SBM patients compared with convexity meningioma patients. Anterior/middle SBM patients (n = 62) had significantly and clinically relevantly better HRQOL in SF-36 and EORTC QLQ-BN20 scores than posterior SBM patients (n = 27): physical role functioning (corrected difference 17.1, 95% CI 0.2-34.0), motor dysfunction (-10.1, 95% CI -17.5 to -2.7), communication deficit (-14.2, 95% CI -22.7 to -5.6), and weakness in both legs (-10.1, 95% CI -18.8 to -1.5). SBM patients whose primary treatment was radiotherapy had lower HRQOL scores compared with SBM patients who underwent surgery on two domains: bodily pain (-33.0, 95% CI -55.2 to -10.9) and vitality (-18.9. 95% CI -33.7 to -4.1). Tumor location and treatment modality did not result in significant differences in neurocognitive functioning, although 44% of SBM patients had deficits in at least one domain.

CONCLUSIONS: In the long term, SBM patients do not experience significantly more sequelae in HRQOL and neurocognitive functioning than do controls or patients with convexity meningioma. Patients with posterior SBM had poorer HRQOL than anterior/middle SBM patients, and primary treatment with radiotherapy was associated with worse HRQOL. Neurocognitive functioning was not affected by tumor location or treatment modality.

PMID:34598137 | DOI:10.3171/2021.4.JNS203891

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Nevin Manimala Statistics

The role of an anterior approach in the treatment of ankylosing spondylitis-associated cervical fractures: a systematic review and meta-analysis

Neurosurg Focus. 2021 Oct;51(4):E9. doi: 10.3171/2021.7.FOCUS21333.

ABSTRACT

OBJECTIVE: Cervical fractures in patients with ankylosing spondylitis can have devastating neurological consequences. Currently, several surgical approaches are commonly used to treat these fractures: anterior, posterior, and anterior-posterior. The relative rarity of these fractures has limited the ability of surgeons to objectively determine the merits of each. The authors present an updated systematic review and meta-analysis investigating the utility of anterior surgical approaches relative to posterior and anterior-posterior approaches.

METHODS: After a comprehensive literature search of the PubMed, Cochrane, and Embase databases, 7 clinical studies were included in the final qualitative and 6 in the final quantitative analyses. Of these studies, 6 compared anterior approaches with anterior-posterior and posterior approaches, while 1 investigated only an anterior approach. Odds ratios and 95% confidence intervals were calculated where appropriate.

RESULTS: A meta-analysis of postoperative neurological improvement revealed no statistically significant differences in gross rates of neurological improvement between anterior and posterior approaches (OR 0.40, 95% CI 0.10-1.59; p = 0.19). However, when analyzing the mean change in neurological function, patients who underwent anterior approaches had a significantly lower mean change in postoperative neurological function relative to patients who underwent posterior approaches (mean difference [MD] -0.60, 95% CI -0.76 to -0.45; p < 0.00001). An identical trend was seen between anterior and anterior-posterior approaches; there were no statistically significant differences in gross rates of neurological improvement (OR 3.05, 95% CI 0.84-11.15; p = 0.09). However, patients who underwent anterior approaches experienced a lower mean change in neurological function relative to anterior-posterior approaches (MD -0.46, 95% CI -0.60 to -0.32; p < 0.00001). There were no significant differences in complication rates between anterior approaches, posterior approaches, or anterior-posterior approaches, although complication rates trended lower in patients who underwent anterior approaches.

CONCLUSIONS: The results of this review and meta-analysis demonstrated the varying benefits of anterior approaches relative to posterior and anterior-posterior approaches in treatment of cervical fractures associated with ankylosing spondylitis. While reports demonstrated lower degrees of neurological improvement in anterior approaches, they may benefit patients with less-severe injuries if lower complication rates are desired.

PMID:34598150 | DOI:10.3171/2021.7.FOCUS21333

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Nevin Manimala Statistics

Visual deterioration after endonasal endoscopic skull base surgery: causes, treatments, and outcomes

J Neurosurg. 2021 Oct 1:1-11. doi: 10.3171/2021.3.JNS204378. Online ahead of print.

ABSTRACT

OBJECTIVE: Visual deterioration after endoscopic endonasal transsphenoidal surgery (EETS) for sellar and parasellar masses is a rare but serious complication caused by either compressive or ischemic mechanisms. Timely diagnosis and intervention may restore vision if instituted appropriately. The associated risk factors and their relation to the success of intervention are not well understood.

METHODS: The authors examined a series of 1200 consecutive EETS cases performed by the senior author at Weill Cornell/NewYork-Presbyterian Hospital from 2010 to 2020. Cases with postoperative visual deterioration were identified. Pre- and postoperative clinical data, mechanism of visual decline, latency to intervention, and long-term visual outcome were retrospectively collected and analyzed with appropriate statistical methods.

RESULTS: Twenty-one patients (1.75%) complained of early postoperative visual deterioration. The most common pathology associated with postoperative visual loss was craniopharyngioma (7.69%), followed by meningioma (5.43%) and then pituitary adenoma (1.94%). Timely intervention restored vision in 81% of patients for a 0.33% rate of permanent visual deterioration. Average time to visual deterioration was 28.8 hours, and over 70% of patients experienced vision loss within the first 13 hours. Compressive etiology (n = 11), consisting of either hematoma (n = 8) or graft displacement (n = 3), occurred 7.3 hours and 70.3 hours after surgery, respectively, and was more common in adenomas. Acute postoperative visual deterioration was more common in firm closures (4.78%) compared with soft closures (1.03%; p = 0.0006). Ischemic etiology (n = 10) occurred 10.3 hours after surgery and was more common with craniopharyngiomas and meningiomas (p = 0.08). Sixteen patients (76.2%) underwent early reoperation to explore and decompress the optic apparatus. Vision was restored to baseline after reoperation in all 11 compressive cases, whereas 6/10 ischemic cases improved with supplemental oxygen and hypervolemic hypertensive therapy (p = 0.02). Fluid expansion from 8 to 16 hours (p = 0.034) and systolic blood pressure elevation from 32 to 48 hours (p = 0.05) after surgery were significantly higher in those ischemic patients who recovered some vision compared with those with persistent visual deficits.

CONCLUSIONS: Visual deterioration after EETS is a rare event but can be effectively treated if acted upon appropriately and in a timely fashion. Compressive etiology is reversible with early reoperation. Ischemic etiology can be successfully treated in roughly half of cases with supplemental oxygen and hypertensive hypervolemic therapy but may result in permanent visual deterioration if not instituted appropriately or if delayed with unnecessary exploratory surgery.

PMID:34598134 | DOI:10.3171/2021.3.JNS204378

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Nevin Manimala Statistics

Surface acoustic wave attenuation in polycrystals: Numerical modeling using a statistical digital twin of an actual sample

Ultrasonics. 2021 Sep 20;119:106585. doi: 10.1016/j.ultras.2021.106585. Online ahead of print.

ABSTRACT

Grain boundary scattering-induced attenuation and phase-velocity dispersion of Rayleigh-type surface acoustic waves are studied with a time-domain finite-element method (FEM). The FEM simulation incorporates a realistic material model based on matching the spatial two-point correlation function of a Laguerre tessellation with that obtained from optical micrographs of a previously studied aluminum sample. Plane surface acoustic waves are excited in a multitude of statistically equivalent virtual polycrystals, and their surface displacement fields are averaged for subsequent extraction of the coherent-wave attenuation coefficient and phase velocity. Comparisons to previous laser-ultrasonic experiments, an analytical mean-field model, and the FEM results show good agreement in a broad frequency range from about 10 to 130MHz. Observed discrepancies between models and measurement reveal the importance of spatial averaging in the context of mean-field approaches and suggest improvement strategies for future experimental studies and advanced analytical models. A different attenuation power law for Rayleigh waves is found in the stochastic scattering regime compared to bulk acoustic waves.

PMID:34598096 | DOI:10.1016/j.ultras.2021.106585

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Nevin Manimala Statistics

The impact of the national stay-at-home order on emergency department visits for suspected opioid overdose during the first wave of the COVID-19 pandemic

Drug Alcohol Depend. 2021 Aug 28;228:108977. doi: 10.1016/j.drugalcdep.2021.108977. Online ahead of print.

ABSTRACT

BACKGROUND: Although national syndromic surveillance data reported declines in emergency department (ED) visits after the declaration of the national stay-at-home order for COVID-19, little is known whether these declines were observed for suspected opioid overdose.

METHODS: This interrupted time series study used syndromic surveillance data from four states participating in the HEALing Communities Study: Kentucky, Massachusetts, New York, and Ohio. All ED encounters for suspected opioid overdose (n = 48,301) occurring during the first 31 weeks of 2020 were included. We examined the impact of the national public health emergency for COVID-19 (declared on March 14, 2020) on trends in ED encounters for suspected opioid overdose.

RESULTS: Three of four states (Massachusetts, New York and Ohio) experienced a statistically significant immediate decline in the rate of ED encounters for suspected opioid overdose (per 100,000) after the nationwide public health emergency declaration (MA: -0.99; 95 % CI: -1.75, -0.24; NY: -0.10; 95 % CI, -0.20, 0.0; OH: -0.33, 95 % CI: -0.58, -0.07). After this date, Ohio and Kentucky experienced a sustained rate of increase for a 13-week period. New York experienced a decrease in the rate of ED encounters for a 10-week period, after which the rate began to increase. In Massachusetts after a significant immediate decline in the rate of ED encounters, there was no significant difference in the rate of change for a 6-week period, followed by an immediate increase in the ED rate to higher than pre-COVID levels.

CONCLUSIONS: The heterogeneity in the trends in ED encounters between the four sites show that the national stay-at-home order had a differential impact on opioid overdose ED presentation in each state.

PMID:34598100 | DOI:10.1016/j.drugalcdep.2021.108977

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Nevin Manimala Statistics

A novel cluster detection of COVID-19 patients and medical disease conditions using improved evolutionary clustering algorithm star

Comput Biol Med. 2021 Sep 17;138:104866. doi: 10.1016/j.compbiomed.2021.104866. Online ahead of print.

ABSTRACT

With the increasing number of samples, the manual clustering of COVID-19 and medical disease data samples becomes time-consuming and requires highly skilled labour. Recently, several algorithms have been used for clustering medical datasets deterministically; however, these definitions have not been effective in grouping and analysing medical diseases. The use of evolutionary clustering algorithms may help to effectively cluster these diseases. On this presumption, we improved the current evolutionary clustering algorithm star (ECA*), called iECA*, in three manners: (i) utilising the elbow method to find the correct number of clusters; (ii) cleaning and processing data as part of iECA* to apply it to multivariate and domain-theory datasets; (iii) using iECA* for real-world applications in clustering COVID-19 and medical disease datasets. Experiments were conducted to examine the performance of iECA* against state-of-the-art algorithms using performance and validation measures (validation measures, statistical benchmarking, and performance ranking framework). The results demonstrate three primary findings. First, iECA* was more effective than other algorithms in grouping the chosen medical disease datasets according to the cluster validation criteria. Second, iECA* exhibited the lower execution time and memory consumption for clustering all the datasets, compared to the current clustering methods analysed. Third, an operational framework was proposed to rate the effectiveness of iECA* against other algorithms in the datasets analysed, and the results indicated that iECA* exhibited the best performance in clustering all medical datasets. Further research is required on real-world multi-dimensional data containing complex knowledge fields for experimental verification of iECA* compared to evolutionary algorithms.

PMID:34598065 | DOI:10.1016/j.compbiomed.2021.104866

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Nevin Manimala Statistics

The pretreatment platelet count predicts survival outcomes of diffuse large B-cell lymphoma: An analysis of 1007 patients in the rituximab era

Leuk Res. 2021 Sep 25;110:106715. doi: 10.1016/j.leukres.2021.106715. Online ahead of print.

ABSTRACT

BACKGROUND: The prognostic value of platelet count in diffuse large B-cell lymphoma (DLBCL) has not been extensively investigated. We aimed to examine the association of pretreatment platelet count with disease features, and further examine the prognostic significance of platelet count in DLBCL treated with the R-CHOP regimen.

METHODS: Patients with DLBCL diagnosed between Jan 1 st, 2005 and Dec 31 st, 2018 at Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. Propensity score matching (PSM) was used to balance confounding factors.

RESULTS: A total of 1007 eligible patients who received frontline R-CHOP or R-CHOP-like regimens were included in this study. The optimal cutoff value of platelet count was 157 × 109/L, as determined by the Maximally Selected Rank Statistics method. Patients with the platelet count ≤157 × 109/L had significantly inferior overall survival (OS) (5-year OS, 44.4 % vs. 74.9 %, P < 0.001) and progression-free survival (PFS) (5-year PFS, 35.5 % vs. 65.9 %, P < 0.001) than those with the platelet count >157×109/L. Multivariate analyses showed that pretreatment platelet count ≤ 157 × 109/L was an adversely independent prognostic factor for OS (hazard ratio [HR] 1.960, 95 % confidence interval [CI] 1.418-2.709, P<0.001) and PFS (HR 1.443, 95 %CI 1.080-1.927, P = 0.013). The PSM analysis and subgroup analyses further confirmed the significantly negative impact of low platelet count on OS and PFS.

CONCLUSION: The pretreatment platelet count may be a simple, cost-effective and useful prognostic factor in DLBCL patients treated with frontline R-CHOP regimens. Further investigation is warranted to elucidate the biologic mechanism underlying the prognostic significance of platelet count in DLBCL.

PMID:34598076 | DOI:10.1016/j.leukres.2021.106715

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Nevin Manimala Statistics

Testosterone and cortisol do not predict rejecting harm or maximizing outcomes in sacrificial moral dilemmas: A preregistered analysis

Horm Behav. 2021 Sep 28;136:105063. doi: 10.1016/j.yhbeh.2021.105063. Online ahead of print.

ABSTRACT

Contemporary moral psychology explores the biological underpinnings of morality, including how neuromodulators influence moral judgment and decision making. Some studies suggest that higher circulating testosterone is associated with increased acceptance of sacrificial harm, such as killing one person to save five lives, consistent with utilitarian ethics and inconsistent with deontological ethics. However, most studies employ conventional analytic techniques that conflate concern about outcomes with reduced concern about sacrificial harm, many are statistically underpowered, and none examine potential regulating effects of cortisol. Therefore, we examined whether salivary concentrations of testosterone and cortisol jointly predict sacrificial dilemma judgments among a large sample of undergraduates (n = 199). We utilized an advanced cognitive modeling technique (process dissociation) to independently assess sensitivity to causing harm and maximizing outcomes, preregistering the prediction that higher testosterone would predict reduced harm-rejection rather than increased concern for outcomes, especially among people low in cortisol. However, neither testosterone, nor cortisol, nor their interaction predicted sacrificial dilemma response tendencies. Such findings raise questions about the robustness of past evidence suggesting links between testosterone and sacrificial dilemma judgments.

PMID:34598057 | DOI:10.1016/j.yhbeh.2021.105063