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A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing an ambiguity between the planetary and binary-source interpretations. In this paper, we present the analysis of the microlensing event MOA-2012-BLG-486, for which the light curve exhibits a short-lived perturbation. Routine modeling not considering data taken in different passbands yields a best-fit planetary model that is slightly preferred over the best-fit binary-source model. However, when allowed for a change in the color during the perturbation, we find that the binary-source model yields a significantly better fit and thus the degeneracy is clearly resolved. This event not only signifies the importance of considering various interpretations of short-term anomalies, but also demonstrates the importance of multi-band data for checking the possibility of false-positive planetary signals. [ABSTRACT FROM AUTHOR]

Background: Various essential thrombocythemia (ET)-related stroke mechanisms have been proposed, including microcirculatory disturbance due to coagulopathy, vasculitis, and embolism due to thrombus formation in large vessels. However, the stroke mechanism in ET remains largely unexplored. The purpose of this study was to evaluate magnetic resonance image (MRI) features of ischemic stroke in ET and determine the potential stroke mechanism., Methods: We retrospectively collected data from 21 acute ischemic stroke patients with ET who were admitted to two stroke centers between 2010 and 2023. ET was diagnosed according to the World Health Organization criteria. We evaluated MRI features including the diffusion-weighted image (DWI) lesion pattern, and the presence of hemorrhagic transformation and intracranial artery steno-occlusive lesion, as well as other etiological workup results., Results: Of 21 patients, 20 exhibited multiple ischemic lesions on DWI, mainly within a single vascular territory. Cortical infarcts were observed in 19 patients. Hemorrhagic transformation occurred in 15 patients. Additionally, 15 patients had intracranial steno-occlusive arteries, which regressed to normal in 11 patients during follow-up. Out of all patients, only 2 had potential causes of stroke other than ET (1 with atrial fibrillation and 1 with intracranial atherosclerotic stenosis). The remaining 19 patients had ET as the only identified potential cause., Conclusions: MRI features, including DWI lesion pattern in ischemic stroke patients with ET, suggested embolic etiology despite the absence of major embolic sources. Intra-arterial thrombus appears to be part of the stroke mechanism related to ET and may contribute to ischemic stroke in ET., Competing Interests: Declaration of competing interest The authors have no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background and Purpose: The susceptibility vessel sign, a hypointense signal on MR T2-weighted gradient-recalled echo images, is associated with erythrocyte-predominant thrombi, which are often present in cardioembolism. In contrast, cancer-associated hypercoagulability (CAH)-related stroke, which is presumably caused by fibrin-predominant thrombi, is associated with the absence of the susceptibility vessel sign. We hypothesized that the prevalence of the susceptibility vessel sign may be helpful in distinguishing CAH-related stroke from cardioembolism. This study attempted to validate this hypothesis and investigated the usefulness of the susceptibility vessel sign in differentiating CAH-related stroke from cardioembolism., Materials and Methods: We retrospectively studied patients with both CAH-related stroke (CAH group) and cardioembolism (cardioembolism group) who had major cerebral artery occlusion on MRA that was performed within 6 hours of stroke onset. All patients visited our department from 2015 to 2021. CAH-related stroke was defined as the following: 1) complication of active cancer, 2) pretreatment D-dimer value of >3 μg/mL, 3) multiple vascular territory infarctions, and 4) lack of any other specifically identified causes of stroke. We compared susceptibility vessel sign positivity rates within each group. Multivariable logistic regression analysis was used to assess the association between the absence of the susceptibility vessel sign and CAH-related stroke., Results: Of 691 patients with CAH-related stroke or cardioembolism, major cerebral artery occlusion was observed in 10 patients in the CAH group and 198 patients in the cardioembolism group. The absence of the susceptibility vessel sign was identified in 55 of 208 patients and was significantly more frequent in the CAH group versus the cardioembolism group (90% versus 24%, P  < .05). For predicting CAH-related stroke, the absence of the susceptibility vessel sign demonstrated a sensitivity of 90% (95% CI, 59%-99%), specificity of 78% (95% CI, 71%-83%), a positive predictive value of 18% (95% CI, 10-31), a negative predictive value of 99% (95% CI, 96%-99%), and a likelihood ratio of 4.06. Multivariable logistic regression analysis revealed that the absence of the susceptibility vessel sign was independently associated with CAH-related stroke (OR, 43; 95% CI, 6.8-863; P  < .01)., Conclusions: The absence of the susceptibility vessel sign was more frequent in CAH-related stroke than in cardioembolism. These findings could potentially be helpful for clinical management and differentiating cardioembolism and CAH-related stroke., (© 2024 by American Journal of Neuroradiology.)

Introduction: The aim of this study was to determine the safety and efficacy of intravenous (IV) alteplase at 0.6 mg/kg for patients with acute wake-up or unclear-onset strokes in clinical practice., Methods: This multicenter observational study enrolled acute ischemic stroke patients with last-known-well time &gt;4.5 h who had mismatch between DWI and FLAIR and were treated with IV alteplase. The safety outcomes were symptomatic intracranial hemorrhage (sICH) after thrombolysis, all-cause deaths, and all adverse events. The efficacy outcomes were favorable outcome defined as an mRS score of 0-1 or recovery to the same mRS score as the premorbid score, complete independence defined as an mRS score of 0-1 at 90 days, and change in NIHSS at 24 h from baseline., Results: Sixty-six patients (35 females; mean age, 74 ± 11 years; premorbid complete independence, 54 [82%]; median NIHSS on admission, 11) were enrolled at 15 hospitals. Two patients (3%) had sICH. Median NIHSS changed from 11 (IQR, 6.75-16.25) at baseline to 5 (3-12.25) at 24 h after alteplase initiation (change, -4.8 ± 8.1). At discharge, 31 patients (47%) had favorable outcome and 29 (44%) had complete independence. None died within 90 days. Twenty-three (35%) also underwent mechanical thrombectomy (no sICH, NIHSS change of -8.5 ± 7.3), of whom 11 (48%) were completely independent at discharge., Conclusions: In real-world clinical practice, IV alteplase for unclear-onset stroke patients with DWI-FLAIR mismatch provided safe and efficacious outcomes comparable to those in previous trials. Additional mechanical thrombectomy was performed safely in them., (© 2023 S. Karger AG, Basel.)

Study Design: Retrospective review of spine surgery patients with new major neurologic complication., Objective: To define the causes and severity of new neurologic damage to the spinal cord or cauda equina caused by spinal surgery., Materials and Methods: Consult records were reviewed for all postoperative spine surgery patients referred to a tertiary spinal cord injury rehabilitation center over a 12-year period. Any patients with a new perioperative surgery-related decrement in American Spinal Injury Association (ASIA) Impairment Scale (AIS), loss of bowel or bladder function, or loss of ability to ambulate were examined and final 1-year gaps for neurologic loss reported., Results: 64 patients had a new perioperative major neurologic event with: 41% thoracic, 39% cervical, and 20% lumbar; 61% intraoperative, 31% in the immediate 2-week postoperative period, 8% unknown. Chronic myelopathy (44%) was the most common indication. The causes of neurologic injury were postoperative fluid collection (25%), malposition of instrumentation (14%), traumatic decompression (14%), cord infarct (11%), deformity correction (2%), and unknown (34%). Overall, 87% lost the ability to ambulate and 66% lost volitional bowel-bladder control. AIS decrement and loss of ambulation and bowel-bladder function did not differ statistically significantly by surgical indication. However, among the main root causes, traumatic decompressions and cord infarcts had significantly worse neurologic deterioration than fluid collections or malposition of instrumentation., Conclusion: The relative rate of major neurologic injury in spine surgery is higher in thoracic and cervical cases at spinal cord levels, especially when done for myelopathy, even though lumbar surgeries are most common. The most common causes of neurologic injury were potentially avoidable postoperative fluid collections, malposition of instrumentation, and traumatic decompression., (© 2021. The Author(s), under exclusive licence to International Spinal Cord Society.)

Study Design: Retrospective case series., Objectives: To examine the patterns and relative rates of occurrence of spinal cord injury (SCI) in automobiles compared to motorcycles and bicycles., Setting: Los Angeles County, California., Methods: A retrospective chart review of SCI consults at Rancho Los Amigos National Rehabilitation Center in Los Angeles County, California between 2003 and 2013 were selected and screened for a mechanism of injury involving a vehicular accident. Chart review was performed to determine neurological levels and extent of impairment, which were graded according to the International Standards for Neurological Classification of Spinal Cord Injury., Results: We identified 398 cases of SCI from 2003 to 2013 that fit the inclusion criteria. Overall, the relative percentages of ASIA impairment scale (AIS) A/B/C/D did not differ statistically across automobiles, motorcycles, or bicycles. When stratified by spinal region, motorcycles had a higher percentage of thoracic SCIs compared to automobiles. Automobiles resulted in more cervical SCIs with few injuries in the lumbar region. Bicycle patterns followed automobiles, not motorcycles. Thoracic SCIs were more likely graded motor complete than cervical or lumbar injuries, regardless of the mechanism., Conclusions: Automobile, motorcycle, and bicycle related SCIs occur primarily in the cervicothoracic region. SCIs due to motorcycle accidents have a higher predilection for the thoracic region, and there is a statistically higher percentage of motor complete injuries. A higher percentage of cervical SCIs occur as a result of automobile and bicycle accidents. Extrapolations from motor vehicle usage data suggest that the relative rate of occurrence of SCI for motorcycles is higher than for automobiles.

A 2.5-year-old male French Bulldog was evaluated for seizures. Cranial magnetic resonance imaging (MRI) suggested a glioma in the left piriform area. Radiation therapy (RT) and continuous chemotherapy were administered. Although the lesion had regressed significantly 2 months after RT, a follow-up MRI revealed meningeal enhancement in the left piriform area, which expanded further, with hydrocephalus, by day 310 (8 months after RT). Because of the poor prognosis, the dog was euthanized on day 356 and necropsy was performed. Histopathological examination confirmed anaplastic oligodendroglioma with leptomeningeal dissemination. This case suggests that the possibility of leptomeningeal dissemination and hydrocephalus should be considered even after RT and chemotherapy for anaplastic oligodendroglioma.

This study attempted to investigate the effects of the target shape and the movement direction on the pointing time using an eye-gaze input system and extend Fitts' model so that these factors are incorporated into the model and the predictive power of Fitts' model is enhanced. The target shape, the target size, the movement distance, and the direction of target presentation were set as within-subject experimental variables. The target shape included: a circle, and rectangles with an aspect ratio of 1:1, 1:2, 1:3, and 1:4. The movement direction included eight directions: upper, lower, left, right, upper left, upper right, lower left, and lower right. On the basis of the data for identifying the effects of the target shape and the movement direction on the pointing time, an attempt was made to develop a generalized and extended Fitts' model that took into account the movement direction and the target shape. As a result, the generalized and extended model was found to fit better to the experimental data, and be more effective for predicting the pointing time for a variety of human-computer interaction (HCI) task using an eye-gaze input system., (Copyright © 2017. Published by Elsevier Ltd.)

Background Context: We receive a large number of patients with spinal cord injury (SCI) due to penetrating gunshot wounds (GSW) at our national rehabilitation center. Although many patients are labeled American Spinal Injury Association (ASIA) B sensory incomplete because of sensory sparing, especially deep anal pressure, with purported prognostic value, we have not observed a clinical difference from patients labeled ASIA A complete. We hypothesized that sensory sparing, if meaningful, should reduce the occurrence of pressure ulcers., Purpose: To determine if ASIA classifications A and B are important distinctions for patients with SCIs secondary to civilian gunshot wounds., Design/setting: A retrospective chart review was performed on all patients with civilian gunshot-induced SCI transferred to Rancho Los Amigos Rehabilitation Center between 1999 and 2014. Outcome measures were occurrence of pressure ulcers and surgical intervention for pressure ulcers., Patient Sample: We included a total of 487 patients who sustained civilian gunshot wounds to the spine and were provided care at Rancho Los Amigos Rehabilitation Center from 2001 to 2014., Outcome Measures: Occurrence of pressure ulcers and surgical intervention for pressure ulcers among patients who suffered civilian-induced gunshot wounds to the spine., Methods: Retrospective chart review identified 487 SCIs due to gunshot wounds that were treated at Rancho Los Amigos from 2001 to 2014. Injury characteristics including ASIA classification, pressure ulcers, and pressure ulcer surgeries were recorded. Comprehensive surgical data were obtained for all patients. Chart reviews and telephone interviews were performed to determine the occurrence of any pressure ulcers and pressure ulcer surgeries. Statistical analysis was performed to compare data by spinal region and ASIA grade. There were no conflicts of interest from any of the authors, and there was no funding obtained for this study., Results: There was no statistical difference for cervical ASIA A versus ASIA B for the occurrence of pressure ulcers or the percentage requiring surgery, nor for thoracic A versus B. When grouped, there was a statistically higher occurrence of pressure ulcers in cervical A or B classification than in thoracic A or B classification, but a higher rate of surgery for thoracic A or B classification. Lumbosacral cauda equina levels were not statistically different in occurrence of pressure ulcers or pressureulcer surgery by ASIA grades A-D. Overall, when grouped C1-T12, cord-level cervicothoracic A and B classifications were statistically equivalent. C1-T12 cord level C or D classification with motor sparing had statistically lower occurrence and need of surgery for pressure ulcers and were equivalent to lumbosacral cauda equina level A-D., Conclusion: ASIA A and B distinctions are not meaningful at spinal cord levels in the cervicothoracic spine due to gunshot wounds as shown by similar occurrence of pressure ulcers and pressure ulcer surgery, and should be treated as if the same. Meaningful decrease of pressure ulcers at cord levels does not occur until there is motor sparing ASIA C or D. Furthermore, cauda equina lumbosacral injuries are a lower risk, which is independent of ASIA grade A-D and statistically equivalent to cord level C or D. Motor sparing at cord levels or any cauda equina level is most determinative neurologically for the occurrence of pressure ulcers or pressure ulcer surgery., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Study Design: Retrospective chart review., Objective: Assess appropriate utilization of surgery for civilian gunshot-induced spinal cord injuries (CGSWSCI) according to literature standards in a large cohort., Summary of Background Data: CGSWSCI are mechanically stable injuries that rarely require surgery. Nonetheless, we continue to see high numbers of these patients undergo surgical treatment. This study compares indications for surgeries performed in a large cohort of CGSWSCI patients to established indications for surgical management of such injuries. The rate of over-utilization of surgical management was calculated., Methods: Four hundred eighty-nine CGSWSCI patients transferred for rehabilitation to our institution between 2000 and 2014 were identified. Retrospective chart review was performed to identify patients who underwent initial surgical treatment, the specific surgeries performed, and indications given. We assessed appropriateness of surgery according to literature standards. Patients treated surgically were followed to assess for complications and the need for additional intervention and compared to nonsurgical patients. Secondarily, visual analog scale pain scores (0-10) and patient perceived improvement were compared between surgical and nonsurgical patients after telephone survey of both groups., Results: Of 489 patients, 91 (18%) underwent initial surgery. Of 91 surgeries, 69 (75%) were not indicated by literature standards. Five of 91 (5.5%) of initially operated patients required a secondary surgery compared with two of 398 (0.5%) of the nonoperative group (P = 0.003). Over-utilization rate of the entire cohort was 14.1%. No difference was seen for pain scores or patient perceived improvement between operative and nonoperative patients., Conclusion: We report a high overutilization rate (14%) of surgery for CGSWSCI in our cohort. Surgical management was associated with higher infection and secondary surgery rates compared to nonsurgical management. Surgery done without a clear, demonstrable benefit poses unnecessary risk to patients and accumulates unwarranted healthcare costs., Level of Evidence: 3.

OBJECTIVE Penetrating gunshot wounds (GSWs) to the spinal column are stable injuries and do not require spinal orthoses or bracing postinjury. Nonetheless, a high number of GSW-related spinal cord injury (SCI) patients are referred with a brace to national rehabilitation centers. Unnecessary bracing may encumber rehabilitation, create skin breakdown or pressure ulcers, and add excessive costs. The aim of this study was to confirm the stability of spinal column injuries from GSWs and quantify the overutilization rate of bracing based on long-term follow-up. METHODS This retrospective cohort study was performed at a nationally renowned rehabilitation center. In total, 487 GSW-related SCI patients were transferred for rehabilitation and identified over the last 14 years. Retrospective chart review and telephone interviews were conducted to identify patients who were braced at the initial treating institution and determine if late instability, deformity, or neurological deterioration resulted in secondary surgery or intervention. In addition, 396 unoperated patients were available for analysis after 91 patients were excluded for undergoing an initial destabilizing surgical dissection or laminectomy, thereby altering the natural history of the injury. All of these 396 patients who presented with a brace had bracing discontinued upon reaching the facility. RESULTS In total, 203 of 396 patients were transferred with a spinal brace, demonstrating an overutilization rate of 51%. No patients deteriorated neurologically or needed later surgery for spinal column deformity or instability attributable to the injury. All patients had stable injuries. The patterns of injury and severity of neurological injury did not vary between patients who were initially braced or unbraced. The average follow-up was 7.8 years (range 1-14 years) and the average age was 25 years (range 10-62 years). CONCLUSIONS The incidence of brace overutilization for penetrating GSW-related SCI was 51%. Long-term follow-up in this study confirmed that these injuries were stable and thus did not require bracing. No patients deteriorated neurologically, whether or not they were initially braced. The unnecessary use of spinal orthoses increases costs and patient morbidity. Reeducation and dissemination of this information is warranted.