Diagnostic performance of computed tomography-digital subtraction angiography and conventional magnetic resonance imaging for evaluating the vascularity of osseous spinal tumors.

BACKGROUND AND PURPOSE: Patients with hypervascular spinal tumors may have severe blood loss during tumor resection, which increases the risks of perioperative morbidity and mortality. However, the preoperative evaluation of tumor vascularity may be challenging; moreover, the reliability of the data obtained in conventional preoperative noninvasive imaging is debatable. In this study, we compared conventional magnetic resonance imaging (MRI) and subtraction computed tomography angiography (CTA) in terms of their performance in vascularity evaluation. The catheter digital subtraction angiography (DSA) technique was used as a reference standard. METHODS: This study included 123 consecutive patients with spinal tumor who underwent subtraction CTA, catheter DSA, and subsequent surgery between October 2015 and October 2021. Data regarding qualitative and semiquantitative subtraction CTA parameters and conventional MRI signs were collected for comparison with tumor vascularity graded through catheter DSA. The diagnostic performance of qualitative CTA, quantitative CTA, and conventional MRI in assessing spinal tumor vascularity was analyzed. RESULTS: Qualitative subtraction CTA was the best noninvasive imaging modality in terms of diagnostic performance (area under the receiver operating characteristic curve [AUROC], 0.95). Quantitative CTA was relatively inferior (AUROC, 0.87). MRI results had low reliability (AUROC, 0.51 to 0.59). Intratumoral hemorrhage and prominent foraminal venous plexus were found to be the specific signs for hypervascularity (specificity 93.2%). CONCLUSIONS: Qualitative subtraction CTA offers the highest diagnostic value in evaluating spinal tumor vascularity, compared to quantitative CTA and MRI. Although conventional MRI may not be a reliable approach, certain MRI signs may have high specificity, which may be crucial for assessing spinal tumor vascularity.

An optimization model for reducing thrombectomy center rotations while maintaining medical accessibility.

BACKGROUND/PURPOSE: This study addresses the delicate balance between healthcare personnel burnout and medical accessibility in the context of endovascular thrombectomy (EVT) services in urban areas. We aimed to determine the minimum number of hospitals providing EVT on rotation each day without compromising patient access. METHODS: Employing an optimization model, we developed shift schedules based on patient coverage rates and volumes during the pre-pandemic (2016-2018) and pandemic (2019-2021) periods. Starting with a minimum of two hospitals on duty per day, we gradually increased to a maximum of eight. Patient coverage rates, defined as the proportion of patients meeting bypass criteria and transported to rotating hospitals capable of EVT, were the primary outcomes. Sensitivity analyses explored the impact of varying patient transport intervals and accumulating patients over multiple years. RESULTS: Results from 7024 patient records revealed patient coverage rates of 92.5% (standard deviation [SD] 2.8%) during the pre-pandemic and 91.4% (SD 2.8%) during the pandemic, with at least two rotating hospitals daily. No significant differences were observed between schedules based on the highest patient volume and coverage rate months. A patient coverage rate of 98.99% was achieved with four rotating hospitals per day during the pre-pandemic period, with limited improvement beyond this threshold. Changing patient transport intervals and accumulating patients over six years (p = 0.83) had no significant impact on coverage rates. CONCLUSION: Our optimization model supports reducing the number of daily rotating hospitals by half while preserving a balance between patient accessibility and alleviating strain on medical teams.

The Clinical Outcome of Carotid Blowout Syndrome Showing Non-bleeding Angiography.

OBJECTIVE: Patient with carotid blowout syndrome (CBS) may demonstrated non-bleeding digital subtraction angiography (DSA) without identifying pseudoaneurysm or contrast extravasation. Our objective is to evaluate the clinical outcomes for this specific subset of patients. MATERIALS AND METHODS: A retrospective observational study was conducted on 172 CBS patients who received DSA for evaluation of transarterial embolization (TAE) between 2005 and 2022, of whom 19 patients had non-bleeding DSA and did not undergo TAE. RESULTS: The age (55.2 ± 7.3 vs. 54.8 ± 11.1), male sex (17/19 vs. 135/153), tumor size (5.6 ± 2.4 vs. 5.2 ± 2.2), cancer locations were similar (P > 0.05) between both groups; except for there were more pseudoaneurysm/active bleeding (85.6% vs. 0%) and less vascular irregularity (14.4% vs. 94.7%) in the TAE group (P < 0.001). In the multivariable Cox regression model adjusting for age, sex, and tumor size, non-bleeding DSA group was independently associated with recurrent bleeding compared to TAE group (adjusted hazard ratio = 3.5, 95% confidence interval: 1.9-6.4, P < 0.001). Furthermore, the presence of vascular irregularity was associated with segmental recurrent bleeding (adjusted HR = 8.0, 95% CI 2.7-23.3, P < 0.001). CONCLUSION: Patient showing non-bleeding DSA thus not having TAE had higher risk of recurrent bleeding, compared to patient who received TAE. Level of Evidence Level 4, Case Series.

Prevalence and clinical features of carotid artery web in patients undergoing endovascular thrombectomy for acute ischemic stroke.

PURPOSE: Carotid artery web (CaW) is a rare focal fibromuscular dysplasia that can lead to embolic strokes with large vessel occlusion. This condition can be effectively treated with endovascular thrombectomy (EVT). Our study aims to assess the prevalence of CaW among patients with acute ischemic stroke (AIS) who underwent EVT and to compare the clinical characteristics of CaW with other carotid artery pathologies. METHODS: We enrolled consecutive patients with AIS who underwent EVT at a single medical center and two regional teaching hospitals in Taiwan from September 2014 to December 2021. We compared CaW with carotid dissection (CaD) and carotid large artery atherosclerosis (CaLAA) in terms of patient demographics and thrombus histological findings. RESULTS: Of the 576 AIS patients who underwent EVT, four (mean age: 50 years) were diagnosed with CaW, resulting in a prevalence of 0.69%. Among these four patients, three experienced successful reperfusion after EVT and achieved functional independence (defined as a modified Rankin Scale score ≤2) three months post-stroke. Importantly, none of the CaW patients suffered a recurrent stroke within one year. Patients with CaW were younger than those with CaD or CaLAA, and exhibited fewer vascular risk factors. Additionally, CaW was associated with distal occlusion sites. The thrombus composition in CaW patients was similar to that in CaD patients. CONCLUSIONS: In conclusion, CaW is a rare finding among Asian patients with carotid artery disease who undergo for AIS. It is more prevalent in younger patients with a limited number of vascular risk factors.

Comparing Low- or Standard-Dose Alteplase in Endovascular Thrombectomy: Insights From a Nationwide Registry.

BACKGROUND: Timely intravenous thrombolysis and endovascular thrombectomy are the standard reperfusion treatments for large vessel occlusion stroke. Currently, it is unknown whether a low-dose thrombolytic agent (0.6 mg/kg alteplase) can offer similar efficacy to the standard dose (0.9 mg/kg alteplase). METHODS: We enrolled consecutive patients in the multicenter Taiwan Registry of Endovascular Thrombectomy for Acute Ischemic Stroke who had received combined thrombolysis (within 4.5 hours of onset) and thrombectomy treatment from January 2019 to April 2023. The choice of low- or standard-dose alteplase was based on the physician's discretion. The outcomes included successful reperfusion (modified Thrombolysis in Cerebral Infarction score, 2b-3), symptomatic intracerebral hemorrhage, 90-day modified Rankin Scale score, and 90-day mortality. The outcomes between the 2 groups were compared using multivariable logistic regression and inverse probability of treatment weighting-adjusted analysis. RESULTS: Among the 2242 patients in the Taiwan Registry of Endovascular Thrombectomy for Acute Ischemic Stroke, 734 (33%) received intravenous alteplase. Patients in the low-dose group (n=360) were older, had more women, more atrial fibrillation, and longer onset-to-needle time compared with the standard-dose group (n=374). In comparison to low-dose alteplase, standard-dose alteplase was associated with a lower rate of successful reperfusion (81% versus 87%; adjusted odds ratio, 0.63 [95% CI, 0.40-0.98]), a numerically higher incidence of symptomatic intracerebral hemorrhage (6.7% versus 3.9%; adjusted odds ratio, 1.81 [95% CI, 0.88-3.69]), but better 90-day modified Rankin Scale score (functional independence [modified Rankin Scale score, 0-2], 47% versus 31%; adjusted odds ratio, 1.91 [95% CI, 1.28-2.86]), and a numerically lower mortality rate (9% versus 15%; adjusted odds ratio, 0.73 [95% CI, 0.43-1.25]) after adjusting for covariates. Similar results were observed in the inverse probability of treatment weighting-adjusted models. The results were consistent across predefined subgroups and age strata. CONCLUSIONS: Despite the lower rate of successful reperfusion and higher risk of symptomatic intracerebral hemorrhage with standard-dose alteplase, standard-dose alteplase was associated with a better functional outcome in patients receiving combined thrombolysis and thrombectomy.

Irregular Antibody Screening Using a Microdroplet Platform.

The screening procedure for antibodies is considered the most tedious among the three pretransfusion operations, i.e., ABO and Rhesus (Rh) typing, irregular antibody screening/identification, and crossmatching tests. The commonly used screening method for irregular antibodies in clinics at present is a manual polybrene test (MP). The MP test involves numerous reagent replacement and centrifuge procedures, and the sample volume is expected to be relatively less. Herein, screening red blood cells (RBCs) and serum irregular antibodies are encapsulated in microdroplets with a diameter of ~300 µm for a hemagglutination reaction. Owing to the advantage of spatial limitation in microdroplets, screening RBCs and irregular antibodies can be directly agglutinated, thereby eliminating the need for centrifugation and the addition of reagents to promote agglutination, as required by the MP method. Furthermore, the results for a large number of repeated tests can be concurrently obtained, further simplifying the steps of irregular antibody screening and increasing accuracy. Eight irregular antibodies are screened using the proposed platform, and the results are consistent with the MP method. Moreover, the volume of blood samples and antibodies can be reduced to 10 µL and 5 µL, respectively, which is ten times less than that using the MP method.

The Extent of Tumor Invasion and Therapeutic Embolization Are Associated with Recurrent Hemorrhage in Patients with External Carotid Artery Blowout Syndrome.

PURPOSE: To explore the optimal strategies of therapeutic embolization for patients with carotid blowout syndrome in the external carotid artery (ECA), who may also present with arterial tumor invasion or necrosis extending to the internal carotid artery (ICA) or common carotid artery (CCA). MATERIALS AND METHODS: The study included 110 patients with ECA blowout between 2005 and 2022. Antecedent cross-sectional imaging features were examined, including tumor size, extent of arterial invasion, and air-containing necrosis. Patients were divided into Groups 1 (n = 53, simultaneous ICA/CCA invasion + ECA therapeutic embolization), 2 (n = 18, simultaneous ICA/CCA invasion + ECA-ICA/CCA therapeutic embolization), and 3 (n = 39, no ICA/CCA invasion + ECA therapeutic embolization). Kaplan-Meier and multivariable Cox regression analyses were performed to evaluate associations of clinical, imaging, and therapeutic embolization characteristics with recurrent bleeding. RESULTS: Multivariable Cox regression revealed that Group 1 was independently associated with a higher risk of recurrent bleeding than that in Group 2 (adjusted hazard ratio, 6.3; 95% CI, 1.7‒23.4; P = .005) and Group 3 (adjusted hazard ratio, 3.8; 95% CI, 1.8‒8.3; P = .001). In the subgroup with simultaneous ICA/CCA invasion, air-containing necrosis around the ICA/CCA was independently associated with recurrent bleeding after therapeutic embolization of the ECA (adjusted hazard ratio, 5.0; 95% CI, 1.8‒13.6; P = .002). CONCLUSIONS: In patients with ECA blowout treated with therapeutic embolization, there was a lower risk of recurrent bleeding when the extents of arterial invasion and therapeutic embolization were concordant. Air-containing necrosis around the ICA/CCA was associated with recurrent bleeding, so extensive therapeutic embolization to the ICA/CCA should be evaluated in such patients.

Association of Ferroptosis with Severity and Outcomes in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy: A Case-control Study.

Ferroptosis, an iron-dependent form of cell death, is characterized by intracellular accumulation of iron and reactive oxygen species-induced lipid peroxidation. Animal experiments have shown the important roles of ferroptosis in ischemic stroke, but the evidence in human stroke is insufficient. This prospective study evaluated the associations between plasma ferroptosis biomarkers at hyperacute stage and long-term outcomes in patients with acute ischemic stroke undergoing endovascular thrombectomy (EVT). The plasma samples were collected immediately before and after EVT (T1 and T2) and at 24 h (T3) for the 126 stroke patients and once for the 50 stroke-free control subjects. Compared with controls, stroke patients had higher 4-hydroxynonenal (4-HNE) levels at T1 and T2 while lower homocysteine and soluble transferrin receptor (sTfR) levels at T3. In stroke patients, higher National Institutes of Health Stroke Scale scores at admission were correlated with higher 4-HNE and lower sTfR levels. Lower Alberta Stroke Program Early CT (ASPECT) scores and larger infarct core volumes on CT perfusion before EVT were correlated with higher 4-HNE and homocysteine levels. After adjusting for significant parameters, homocysteine levels at T2 were significantly associated with poor functional outcome and mortality at 3 months. In the receiver operating characteristic (ROC) models, adding homocysteine levels at T2 and hemoglobin levels to the reference model for predicting poor functional outcome significantly increased the area under the ROC curve. In summary, this study provides evidence that ferroptosis is associated with stroke severity and outcomes in patients with acute ischemic stroke undergoing EVT.

Temporalis and masseter muscle thickness as predictors of post-stroke dysphagia after endovascular thrombectomy.

PURPOSE: Post-stroke dysphagia (PSD) is a common sequela of stroke. Given the association between dysphagia and sarcopenia, we aimed to investigate the association between PSD and temporal muscle thickness (TMT) and masseter muscle thickness (MMT) following endovascular thrombectomy (EVT) in patients with large-vessel occlusion (LVO). METHODS: This retrospective cohort study included hospitalized patients with LVO stroke who underwent EVT between January 1, 2018, and October 31, 2022. TMT and MMT were measured using brain computed tomography (CT) angiography. The correlation between relevant clinicodemographic factors and both TMT and MMT was examined. The relationship between each of two parameters (TMT and MMT) and PSD, which was defined as the retention of the nasogastric (NG) tube at 4 and 12 weeks, was evaluated in adjusted logistic regression models. RESULTS: Among the 148 participants, the mean TMT and MMT was 5.9 ± 1.6 and 11.2 ± 2.3 mm, respectively. Lower age, male sex, higher body mass index (BMI), higher albumin levels, and a lower initial National Institute of Health Stroke Scale (NIHSS) score were associated with higher TMT and MMT (p < 0.05). In the logistic regression analysis adjusted for age, sex, BMI, serum albumin, and NIHSS score, lower TMT and MMT significantly correlated with PSD at weeks 4 and 12 (p < 0.001). CONCLUSION: TMT and MMT are associated with age, sex, BMI, albumin, and the initial NIHSS score. Both TMT and MMT are independent indicators of post-EVT PSD in stroke patients and serve as reliable predictors of NG removal.

Clinical characteristics and prognosis of optic neuritis in Taiwan - a hospital-based cohort study.

BACKGROUND: Optic neuritis (ON) is an inflammatory disease of optic nerve. The distinct etiologies of ON significantly influence its clinical manifestation, neuroimaging findings, and visual outcomes. However, the clinical characteristics might be influenced by the racial differences. The purpose of this study is to investigate the clinical characteristics of various types of ON at a Taiwanese tertiary center. METHODS: This cohort study analyzed 163 patients who received treatment and continued following-up for ON between 2015 and 2022. We selected patients who had been tested for anti-aquaporin-4 antibody (AQP4-Ab) and anti-myelin oligodendrocyte glycoprotein antibody (MOG-Ab). The participants were classified into four groups on the basis of their etiologies, specifically (1) multiple sclerosis (MS)-related, (2) AQP4-Ab-positive, (3) MOG-Ab-positive, or (4) idiopathic ON. The researchers recorded the patients' clinical characteristics, treatment course, magnetic resonance imaging and optical coherence tomography (OCT) findings, and visual outcomes. RESULTS: MOG-Ab-positive group had higher percentages of disk swelling and pain with eye movement. Long optic nerve and perineural enhancement are the hallmarks of MOG-Ab-related ON. The ON relapse rate was higher in AQP4-Ab-positive group. Although members of AQP4-Ab-positive group received immediate steroid pulse therapy, these patients experienced the worst visual outcomes. Moreover, a thinner retinal nerve fiber layer (RNFL) was noted in AQP4-Ab-positive group. MS group had a higher incidence of extra-optic nerve lesions. Multivariate regression identified pretreatment visual acuity and RNFL thickness as the important factors affecting visual outcomes. CONCLUSIONS: This cohort study identified the clinical features of different types of ON. Patients with AQP4-Ab-positive ON had poorer visual outcomes, which may be attributed to multiple relapses and profound nerve damage, as revealed by OCT findings. Patients with MOG-Ab-positive ON displayed long optic nerve enhancement but had more favorable prognoses. Thus, antibody-based classification facilitates treatment and prognosis in ON.

Association of temporalis muscle thickness with functional outcomes in patients undergoing endovascular thrombectomy.

INTRODUCTION: Temporalis muscle thickness (TMT) is a surrogate marker for sarcopenia. This study investigated the association of TMT with clinical outcomes in patients receiving endovascular thrombectomy (EVT) for stroke involving acute large vessel occlusion (LVO). MATERIAL AND METHODS: We enrolled consecutive patients who had undergone EVT between September 2014 and December 2021 at three thrombectomy-capable institutes. TMT was measured through preprocedural computerized tomography angiography. The clinical variables affecting TMT were investigated. The associations between TMT and clinical functional outcomes, defined using the modified Rankin scale, were also studied. RESULTS: A total of 657 patients were included (mean age: 72.0 ± 12.7 years; male: 52.1%). The mean TMT was 6.35 ± 1.84 mm. Younger age, male sex, higher body mass index, and premorbid functional independence were associated with larger TMT in both univariate and multivariate linear regression (P <.05). Ordinal logistic regression revealed that TMT was associated with better clinical outcomes at 90 days (Ptrend = 0.047); multivariate logistic regression indicated that larger TMT was an independent predictor (adjusted odds ratio: 1.14, 95% confidence interval: 1.03-1.27, P = 0.02) of favorable functional independence (modified Rankin scale score: 0-2). The effect was stronger in older patients (≥80 years) than younger patients, as revealed by interaction modeling analysis (Pinteraction = 0.06). CONCLUSION: TMT is associated with age, sex, body mass index, and premorbid functional status. Larger TMT is associated with better outcomes after EVT. The effects of TMT are more pronounced in older adults, indicating that sarcopenia may have influence on stroke outcomes.

DYNC1H1 variant associated with epilepsy: Expanding the phenotypic spectrum.

DYNC1H1 variants are associated with peripheral neuronal dysfunction and brain morphology abnormalities resulting in neurodevelopmental delay. However, few studies have focused on the association between DYNC1H1 variants and epilepsy. Herein, we report a case of drug-resistant focal epilepsy associated with a pathogenic variant of DYNC1H1. We further summarized the clinical, genetic, and neuroimaging characteristics of patients with DYNC1H1 variant-associated epilepsy from the relevant literature. This report expands the phenotypic spectrum of DYNC1H1-related disorder to include early-onset epilepsy, which is frequently associated with neurodevelopmental delay and intellectual disability, malformations of cortical development, and neuromuscular, ophthalmic, and orthopedic involvement.

Efficacy of preoperative embolization for metastatic spinal tumor surgery using angiographic vascularity assessment.

OBJECTIVES: Preoperative embolization (PE) for metastatic spinal tumors is a method of minimizing intraoperative blood loss during aggressive surgery. This study specified angiographic standards and investigated the influence of these and other factors on blood loss in patients with spinal metastases and various pathologies. METHODS: The cohort comprised 126 consecutive patients receiving PE from 2015 to 2021. Their clinical, surgical, and angiographic characteristics were reviewed. Standard angiographic grading was used for vascularity assessment. Degree of embolization was divided into complete (≥ 90%), near complete (67 to < 90%), and partial (< 67%). Logistic regression analysis was used to investigate factors predictive of massive blood loss (> 2500 mL). A proportional odds model was used to assess factors predictive of the degree of embolization. RESULTS: Mean intraoperative blood loss was 1676 mL. Among the patients, 62 had hypervascular tumors and 64 had nonhypervascular tumors, according to the angiographic classification. Intraoperative blood loss differed significantly with embolization degree, both overall (p < 0.001) and in the hypervascular and nonhypervascular groups (p = 0.01 and 0.03). Angiographic hypervascularity, spinal metastasis invasiveness index, and embolization degree were significant predictors of massive blood loss in univariate analysis, but only embolization degree was significant in multivariate analysis. Only the presence of the radiculomedullary artery at the target level was significant in both the univariate and multivariate analyses for embolization degree. CONCLUSIONS: In addition to pathological classification, angiographic vascularity assessment is valuable. Although complete embolization is a reasonable goal, it is challenging to achieve in cases of visible radiculomedullary artery. KEY POINTS: • Angiography has a supplementary role in vascularity assessment for spinal metastatic surgery. • Better embolization degree is associated with less intraoperative blood loss in both angiographic hypervascular and nonhypervascular groups. • Presence of radiculomedullary artery in the target level causes worse embolization outcome.

Serum amyloid A predicts poor functional outcome in patients with ischemic stroke receiving endovascular thrombectomy: a case control study.

BACKGROUND: Post-stroke inflammation contributes to poor outcomes, but its impact on patients with stroke receiving endovascular thrombectomy (EVT) remains unknown. METHODS: We enrolled adult patients with stroke who received EVT, with blood sampling immediately before (T1) and after EVT (T2), and at 24 hours after EVT (T3). Non-stroke controls and patients with non-EVT stroke were also enrolled. The medical information, image findings and levels of serum amyloid A (SAA) and C-reactive protein (CRP) were analyzed to clarify the association with poor functional outcome (modified Rankin Scale 4-6) at 3 months after stroke. RESULTS: A total of 93 patients with stroke receiving EVT, 51 non-stroke controls, and 64 with non-EVT stroke were enrolled in this study. The SAA and CRP levels at T1 to T3 in patients with stroke receiving EVT were higher compared with those in controls (all p<0.001), and their levels at T3 were significantly higher than those at T1 (both p<0.0001) while similar to those in patients with non-EVT stroke. The SAA levels at the three time points were significantly associated with poor functional outcome (p=0.003 to 0.009). Furthermore, adding SAA level at T3 significantly improved the basic prediction model for 3-month poor functional outcome by receiver operating characteristic (ROC) analysis (areas under ROC curves from 0.803 to 0.878, p=0.03). CONCLUSIONS: Our findings demonstrate that plasma levels of SAA at an early stage are significant predictors for poor functional outcomes at 3 months in patients with stroke receiving EVT, indicating the substantial role of systemic inflammation in shaping stroke outcomes following EVT.

Delay of Surgery for Spinal Metastasis due to the COVID-19 Outbreak Affected Patient Outcomes.

OBJECTIVE: The present study is to analyze the effects of the coronavirus disease 2019 (COVID 2019) outbreak and the subsequent lockdown on the outcomes of spinal metastasis patients. METHODS: The study was a retrospective analysis of data from a prospective cohort study. All patients underwent surgical intervention for spinal metastases between January 2019 and December 2021 and had at least 3 months of postoperative follow-up. The primary outcome was overall mortality during the 4 different stages (pre-COVID-19 era, COVID-19 pandemic except in Taiwan, national lockdown, lifting of the lockdown). The secondary outcomes were the oncological severity scores, medical/surgical accessibility, and patient functional outcome during the 4 periods as well as survival/mortality. RESULTS: A total of 233 patients were included. The overall mortality rate was 41.20%. During the Taiwan lockdown, more patients received palliative surgery than other surgical methods, and no total en bloc spondylectomy was performed. The time from surgeon visit to operation was approximately doubled after the COVID-19 outbreak in Taiwan (75.97, 86.63, 168.79, and 166.91 hours in the 4 periods, respectively). The estimated survival probability was highest after the national lockdown was lifted and lowest during the lockdown. In the multivariate analysis, increased risk of mortality was observed with delay of surgery, with emergency surgery having a higher risk with delays above 33 hours, urgent surgery (below 59 and above 111 hours), and elective surgery (above 332 hours). CONCLUSION: The COVID-19 pandemic and related policies have altered daily clinical practice and negatively impacted the survival of patients with spinal metastases.

Outcome of endovascular thrombectomy in patients with end-stage renal disease undergoing dialysis.

BACKGROUND: Patients with end-stage renal disease (ESRD) are often excluded from clinical trials of endovascular thrombectomy (EVT). This study investigated the outcome in these patients. METHODS: From September 2014 to July 2021, all patients undergoing EVT for anterior circulation stroke in two stroke centers in Taiwan were included. They were divided into no renal dysfunction (non-RD, estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2), RD (eGFR <60 mL/min/1.73 m2 but no dialysis), and ESRD undergoing dialysis (ESRD-dialysis). The clinical features and outcomes were compared. RESULTS: Of 482 patients included, there were 20 ESRD-dialysis, 110 RD, and 352 non-RD patients. The Alberta Stroke Program Early CT Score (ASPECTS), National Institutes of Health Stroke Scale (NIHSS), use of intravenous thrombolysis, EVT-related time metrics, and successful recanalization rates were comparable among the three groups. However, the ESRD-dialysis patients had more symptomatic intracerebral hemorrhage (ICH, 15% vs 3.6% vs 3.7%), more contrast-induced encephalopathy (15% vs 1.8% vs 0.9%), and a higher mortality at 90 days (35% vs 18% vs 11%) than the other groups. Multivariable analysis revealed that ESRD-dialysis was associated with a less favorable outcome (OR 0.21, 95% CI 0.04 to 0.77) and more severe disability or mortality (modified Rankin Scale 5 or 6; OR 13.1, 95% CI 3.93 to 48.1) at 90 days. In the ESRD-dialysis group, the patients with premorbid functional dependence had a significantly higher mortality than those without (75% vs 8.3%; P=0.004). CONCLUSION: ESRD-dialysis patients were associated with symptomatic ICH and less favorable outcome at 90 days. Patients with premorbid functional dependency had an excessively high mortality.

Ultrafast DNA Amplification Using Microchannel Flow-Through PCR Device.

Polymerase chain reaction (PCR) is limited by the long reaction time for point-of-care. Currently, commercial benchtop rapid PCR requires 30−40 min, and this time is limited by the absence of rapid and stable heating and cooling platforms rather than the biochemical reaction kinetics. This study develops an ultrafast PCR (<3 min) platform using flow-through microchannel chips. An actin gene amplicon with a length of 151 base-pairs in the whole genome was used to verify the ultrafast PCR microfluidic chip. The results demonstrated that the channel of 56 µm height can provide fast heat conduction and the channel length should not be short. Under certain denaturation and annealing/extension times, a short channel design will cause the sample to drive slowly in the microchannel with insufficient pressure in the channel, causing the fluid to generate bubbles in the high-temperature zone and subsequently destabilizing the flow. The chips used in the experiment can complete 40 thermal cycles within 160 s through a design with the 56 µm channel height and with each thermal circle measuring 4 cm long. The calculation shows that the DNA extension speed is ~60 base-pairs/s, which is consistent with the theoretical speed of the Klen Taq extension used, and the detection limit can reach 67 copies. The heat transfer time of the reagent on this platform is very short. The simple chip design and fabrication are suitable for the development of commercial ultrafast PCR chips.

Posterior Limb of Internal Capsule Infarct Predicts Functional Outcome in Acute Terminal Internal Carotid Artery Occlusion After Thrombectomy.

PURPOSES: This study investigated the impact of posterior limb of internal capsule (PLIC) infarct on outcomes of acute internal carotid artery (ICA) occlusion after endovascular thrombectomy (EVT) and the diagnostic accuracy of pretreatment noncontrast computerized tomography (NCCT) and computerized tomography angiography (CTA) findings. METHODS: Patients who underwent EVT for acute ICA occlusion between September 2014 and August 2020 were included in the study. The patients were dichotomized as PLIC infarct or spared. The risk factors for PLIC infarct were investigated, and the association between infarct patterns and clinical outcomes were assessed using logistic regression analysis. Pretreatment NCCT and CTA findings, including PLIC hypodensity, choroid plexus enhancement (CPE), and posterior cerebral artery (PCA) flow status, were calculated for diagnosis of PLIC infarct. RESULTS: Among 72 patients, the mean age was 70.9 years, and the mean stroke scale was 19.4. PLIC infarct was identified in 15 patients (20.8%). PLIC infarct was associated with worse 90-day functional outcome (P = 0.01, shift test). Lack of CPE is the only independent predictor of PLIC infarct (odds ratio: 127.48, P = 0.001). Lack of CPE and impaired PCA flow produce greater diagnostic accuracy for PLIC infarct than does NCCT hypodensity (area under the receiver operating characteristics curve: 0.85 and 0.76, P = 0.0005 and 0.02, respectively). CONCLUSIONS: In acute ICA occlusion, PLIC infarct is an independent risk factor for worse clinical outcome at 90 days. The lack of CPE was associated with PLIC infarct, and pretreatment CTA can be useful for early diagnosis.

Air-containing necrosis as the imaging predictor for imminent carotid blowout in patients with head and neck cancer.

BACKGROUND AND PURPOSE: Carotid blowout syndrome (CBS) is a devastating complication of head and neck cancer (HNC). In this study, we describe radiological features that can predict imminent (<6 months) carotid blowout in patients with HNC. METHODS: Cross-sectional CT or MRI were interpreted from 25 treated HNC patients with acute CBS and 50 treated HNC patients without CBS (controls). The tumor size and the distance from the tumor to the carotid trunk was measured. The following imaging findings of the tumor were also recorded: carotid trunk involvement, enhancement pattern, and the presence of air-containing necrosis. The odds ratios of imminent CBS for each imaging finding were estimated using a multivariable logistic regression model. RESULTS: Compared to the controls, the CBS group had larger tumors (49 ± 18 mm vs. 38 ± 18 mm, p = 0.017), tumors closer to the carotid trunk (0.5 ± 1.7 mm vs. 8.2 ± 14.2 mm, p < 0.001), a higher prevalence of 360° involvement (60% vs. 18%, p < 0.001), more heterogeneous enhancement patterns (84% vs. 50% p < 0.001), and more air-containing necrosis (40% vs. 2% p < 0.001). After multivariable adjustment, the presence of air-containing necrosis remained a significant risk factor for imminent CBS (OR: 20.1, 95% CI: 1.98-204.00; p = 0.011). CONCLUSION: The presence of air-containing necrosis is associated with a higher risk of imminent CBS. This characteristic imaging finding should be evaluated in the follow-up CT or MRI of HNC patients for early warning.

Expanding resources of endovascular thrombectomy: An optimization model.

BACKGROUND/PURPOSE: Recently optimized models for selecting the locations of hospitals capable of providing endovascular thrombectomy (EVT) did not consider the accuracy of the prehospital stroke scale assessment and possibility of secondary transport. Our study aimed to propose a new model for selecting existing hospitals with intravenous thrombolysis capability to become EVT-capable hospitals. METHODS: A sequential order was provided to upgrade hospitals providing intravenous thrombolysis, using a mixed integer programming model based on current medical resource allocation. In addition, we drafted a centralized plan to redistribute existing EVT resources by redetermining locations of EVT-capable hospitals. Using historical data of 7679 on-scene patients with suspected stroke, the model was implemented to determine the hospital that maximizes the number of patients receiving EVT treatment within call-to-definitive-treatment time. RESULTS: All suspected stroke patients were sent to EVT-capable hospitals directly under the current medical resource allocation model. After upgrading one additional hospital to become an EVT-capable hospital, the percentage of patients receiving definitive treatment within the standard call-to-definitive-treatment time was elevated from 68.82% to 72.97%. In the model, assuming that there is no hospital providing EVT, all patients suspected of stroke will be sent to EVT-capable hospitals directly after upgrading three or more hospitals to be able to provide treatment. CONCLUSION: All patients eligible for acute stroke treatment are sent to EVT-capable hospitals in the simulation under the current medical resource allocation model. This model can be utilized to provide insights for capacity redistribution in other regions.