Background: This study evaluated the use of brainstem score (BSS) on pre-procedural diffusion-weighted imaging (DWI) to predict outcomes after mechanical thrombectomy (MT) in acute basilar artery occlusion (ABAO) patients and compared its predictive effectiveness to the critical area perfusion score (CAPS) on perfusion magnetic resonance imaging (MRI) using RAPID. Methods: This study focused on ABAO patients who underwent MT after MRI at Dong-A University Hospital from 2013 to 2023. Ischemic lesion volume and DWI BSS were measured for all. For the group that underwent perfusion MRI using RAPID, CAPS were measured. The primary end point was a poor outcome at 90 days (modified Rankin scale [mRS], >2). Results: 71 patients had ABAO and underwent MT after MRI. The poor outcome group (66.2%) had significantly larger ischemic lesion volume and higher DWI BSS compared with the good outcome group. In the multiple logistic regression analysis, DWI BSS (odds ratio, 8.27; 95% confidence interval, 1.93-35.50; p<0.01) was an independent predictor of poor outcomes. In 26 patients, CAPS was measured on perfusion MRI. In this subgroup, poor outcome group (50.0%) had higher DWI BSS and CAPS than the good outcome group. In the multiple logistic regression analysis, DWI BSS remained a valid independent predictor for predicting outcomes, but CAPS did not function as an independent predictor. Conclusion In this study, the DWI BSS before MT in ABAO patients emerged as a useful imaging marker for predicting post-procedural outcomes. Its predictive ability is not only comparable to but even superior to CAPS on perfusion MRI.

Objective: Acute coronary syndrome often requires urgent intervention. The 2023 European Society of Cardiology guidelines recommend invasive procedures within 24 hours for high-risk cases. Nevertheless, there have been limited studies on non-ST-segment elevation myocardial infarction (NSTEMI) in South Korea. This study compared the risk of complications based on the timing of intervention. Methods: A retrospective observational study was conducted on patients with chest pain and elevated high-sensitivity troponin T from January to December 2021 in the emergency department. Patients were categorized into early (≤24 hr) and late (>24 hr) intervention groups. Primary outcomes (death, restenosis, or stroke) at 12 months were compared. Survival and subgroup analyses were performed to examine the factors affecting the outcomes in the two groups. Results: Three hundred seventy six patients were enrolled in the study, and 115 patients were excluded. Among 261 patients, 106 and 155 patients were in the early intervention group (≤24 hr), and late intervention group (>24 hr), respectively. The primary outcome (death or restenosis) showed no significant difference (hazard ratio [HR] in the early intervention group at 12 mo; 1.03; 95% confidence interval [CI], 0.63-1.70; P=0.905). However, risk of stroke was lower in the early intervention group (HR in the early, 0.08; 95% CI, 0.00-0.66; P=0.013). Subgroup analysis showed no significant advantage for early intervention. Conclusion In NSTEMI patients, early intervention does not reduce death or restenosis but lowers stroke incidence. No specific risk factors favored early intervention.

Background: and Purpose This study evaluated the diagnostic utility of an anti-signal-recognition particle 54 (anti-SRP54) antibody-based enzyme-linked immunosorbent assay (ELISA) as well as the clinical, serological, and pathological characteristics of patients with SRP immune-mediated necrotizing myopathy (IMNM). Methods: We evaluated 87 patients with idiopathic inflammatory myopathy and 107 healthy participants between January 2002 and December 2023. The sensitivity and specificity of the ELISA for anti-SRP54 antibodies were assessed, and the clinical profiles of patients with antiSRP54 antibodies were determined. Results: The ELISA for anti-SRP54 antibodies had a sensitivity and specificity of 88% and 99%, respectively, along with a test–retest reliability of 0.92 (p<0.001). The 32 patients diagnosed with anti-SRP IMNM using a line-blot immunoassay included 28 (88%) who tested positive for anti-SRP54 antibodies using the ELISA, comprising 12 (43%) males and 16 (57%) females whose median ages at symptom onset and diagnosis were 43.0 years and 43.5 years, respectively. Symptoms included proximal muscle weakness in all 28 (100%) patients, neck weakness in 9 (32%), myalgia in 15 (54%), dysphagia in 5 (18%), dyspnea in 4 (14%), dysarthria in 2 (7%), interstitial lung disease in 2 (7%), and myocarditis in 2 (7%). The median serum creatine kinase (CK) level was 7,261 U/L (interquartile range: 5,086–10,007 U/L), and the median anti-SRP54 antibody level was 2.0 U/mL (interquartile range: 1.0–5.6 U/mL). The serum CK level was significantly higher in patients with coexisting anti-Ro-52 antibodies. Conclusions This study has confirmed the reliability of the ELISA for anti-SRP54 antibodies and provided insights into the clinical, serological, and pathological characteristics of South Korean patients with anti-SRP IMNM.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: and Purpose This study evaluated the diagnostic utility of an anti-signal-recognition particle 54 (anti-SRP54) antibody-based enzyme-linked immunosorbent assay (ELISA) as well as the clinical, serological, and pathological characteristics of patients with SRP immune-mediated necrotizing myopathy (IMNM). Methods: We evaluated 87 patients with idiopathic inflammatory myopathy and 107 healthy participants between January 2002 and December 2023. The sensitivity and specificity of the ELISA for anti-SRP54 antibodies were assessed, and the clinical profiles of patients with antiSRP54 antibodies were determined. Results: The ELISA for anti-SRP54 antibodies had a sensitivity and specificity of 88% and 99%, respectively, along with a test–retest reliability of 0.92 (p<0.001). The 32 patients diagnosed with anti-SRP IMNM using a line-blot immunoassay included 28 (88%) who tested positive for anti-SRP54 antibodies using the ELISA, comprising 12 (43%) males and 16 (57%) females whose median ages at symptom onset and diagnosis were 43.0 years and 43.5 years, respectively. Symptoms included proximal muscle weakness in all 28 (100%) patients, neck weakness in 9 (32%), myalgia in 15 (54%), dysphagia in 5 (18%), dyspnea in 4 (14%), dysarthria in 2 (7%), interstitial lung disease in 2 (7%), and myocarditis in 2 (7%). The median serum creatine kinase (CK) level was 7,261 U/L (interquartile range: 5,086–10,007 U/L), and the median anti-SRP54 antibody level was 2.0 U/mL (interquartile range: 1.0–5.6 U/mL). The serum CK level was significantly higher in patients with coexisting anti-Ro-52 antibodies. Conclusions This study has confirmed the reliability of the ELISA for anti-SRP54 antibodies and provided insights into the clinical, serological, and pathological characteristics of South Korean patients with anti-SRP IMNM.

Background: and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation. Methods: We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months. Results: The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections. Conclusions This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.

Background: This study evaluated the use of brainstem score (BSS) on pre-procedural diffusion-weighted imaging (DWI) to predict outcomes after mechanical thrombectomy (MT) in acute basilar artery occlusion (ABAO) patients and compared its predictive effectiveness to the critical area perfusion score (CAPS) on perfusion magnetic resonance imaging (MRI) using RAPID. Methods: This study focused on ABAO patients who underwent MT after MRI at Dong-A University Hospital from 2013 to 2023. Ischemic lesion volume and DWI BSS were measured for all. For the group that underwent perfusion MRI using RAPID, CAPS were measured. The primary end point was a poor outcome at 90 days (modified Rankin scale [mRS], >2). Results: 71 patients had ABAO and underwent MT after MRI. The poor outcome group (66.2%) had significantly larger ischemic lesion volume and higher DWI BSS compared with the good outcome group. In the multiple logistic regression analysis, DWI BSS (odds ratio, 8.27; 95% confidence interval, 1.93-35.50; p<0.01) was an independent predictor of poor outcomes. In 26 patients, CAPS was measured on perfusion MRI. In this subgroup, poor outcome group (50.0%) had higher DWI BSS and CAPS than the good outcome group. In the multiple logistic regression analysis, DWI BSS remained a valid independent predictor for predicting outcomes, but CAPS did not function as an independent predictor. Conclusion In this study, the DWI BSS before MT in ABAO patients emerged as a useful imaging marker for predicting post-procedural outcomes. Its predictive ability is not only comparable to but even superior to CAPS on perfusion MRI.

Objective: Acute coronary syndrome often requires urgent intervention. The 2023 European Society of Cardiology guidelines recommend invasive procedures within 24 hours for high-risk cases. Nevertheless, there have been limited studies on non-ST-segment elevation myocardial infarction (NSTEMI) in South Korea. This study compared the risk of complications based on the timing of intervention. Methods: A retrospective observational study was conducted on patients with chest pain and elevated high-sensitivity troponin T from January to December 2021 in the emergency department. Patients were categorized into early (≤24 hr) and late (>24 hr) intervention groups. Primary outcomes (death, restenosis, or stroke) at 12 months were compared. Survival and subgroup analyses were performed to examine the factors affecting the outcomes in the two groups. Results: Three hundred seventy six patients were enrolled in the study, and 115 patients were excluded. Among 261 patients, 106 and 155 patients were in the early intervention group (≤24 hr), and late intervention group (>24 hr), respectively. The primary outcome (death or restenosis) showed no significant difference (hazard ratio [HR] in the early intervention group at 12 mo; 1.03; 95% confidence interval [CI], 0.63-1.70; P=0.905). However, risk of stroke was lower in the early intervention group (HR in the early, 0.08; 95% CI, 0.00-0.66; P=0.013). Subgroup analysis showed no significant advantage for early intervention. Conclusion In NSTEMI patients, early intervention does not reduce death or restenosis but lowers stroke incidence. No specific risk factors favored early intervention.