Potential authentication of re-esterified triacylglycerol-type omega-3 oils using multivariate analysis of lipid profiles.

This study aimed to authenticate re-esterified triacylglycerol (rTG)-type omega-3 oils prone to adulteration with fatty acid ethyl ester (FAEE)-type oils via hierarchical cluster analysis (HCA) and principal component analysis (PCA) of their lipid profiles. A total of 104 rTG-type omega-3 oil samples, consisting of seven authentic (two commercial and five laboratory-made), 60 adulterated, and 37 unauthenticated commercial samples, were analyzed for their acylglycerol, FAEE, and total EPA/DHA contents. Type 1 authentic samples contained higher triacylglycerols (TG) (63.0-86.3 wt%), lower diacylglycerols (DG) (8.1-31.5 wt%), and no FAEE compared to type 2 authentic samples (36.9-62.1 wt% TG, 9.4-36.9 wt% DG, and 14.9-27.3 wt% FAEE). HCA and PCA differentiated authentic samples from adulterated samples, although type 2 samples were closer to adulterated samples. Both analyses showed that 30/37 commercial samples exhibited higher similarity in lipid profiles to authentic samples than to adulterated samples, indicating their potential for authentication.

Fatty acids and epigenetics in health and diseases.

Lipids are crucial for human health and reproduction and include diverse fatty acids (FAs), notably polyunsaturated FAs (PUFAs) and short-chain FAs (SCFAs) that are known for their health benefits. Bioactivities of PUFAs, including ω-6 and ω-3 FAs as well as SCFAs, have been widely studied in various tissues and diseases. Epigenetic regulation has been suggested as a significant mechanism affecting the progression of various diseases, including cancers and metabolic and inflammatory diseases. Epigenetics encompasses the reversible modulation of gene expression without altering the DNA sequence itself, mediated by mechanisms such as DNA methylation, histone acetylation, and chromatin remodeling. Bioactive FAs have been demonstrated to regulate gene expression via epigenetic modifications that are potentially important for modulating metabolic control and disease risk. This review paper discusses the evidence in support of bioactive FAs, including ω-6 and ω-3 FAs and SCFAs, eliciting various disease prevention via epigenetic regulation including methylation or acetylation.

Concentration of docosahexaenoic acid from tuna oil via a two lipase-catalyzed reaction.

Docosahexaenoic acid (DHA) was concentrated successfully in the glyceride fractions from tuna oil via a two-step enzyme reaction involving hydrolysis and ethanolysis. In the first step, Candida rugosa lipase-catalyzed hydrolysis was carried out to concentrate DHA in the glyceride fractions. The DHA content in the glyceride fraction after hydrolysis increased from 30% in the initial tuna oil to 46%. In the second step, Lipozyme RM IM-catalyzed ethanolysis was conducted with the reaction mixture from the first step to further concentrate DHA in the glyceride fraction. In this step, the reaction mixture obtained from the first step was employed directly in Lipozyme RM IM-catalyzed ethanolysis without additional steps needed to remove free fatty acid. Finally, DHA was concentrated from an initial content of 30% in the tuna oil to 68.4% in the glyceride fractions via a novel two-step enzyme reaction strategy.

Evaluation of sterols as markers of fungal spoilage in red pepper powder.

Red pepper powder (RPP) made from ground dried red pepper (Capsicum annuum L.) is prone to adulteration with fungal-spoiled RPP to gain unfair profits in Korea. This study aimed to investigate the effects of fungal infection on the ergosterol and phytosterol content of RPP and evaluate the potential of the sterol content as a marker for identifying fungal-spoiled RPP. Ergosterol was detected only in fungal-spoiled RPP and not in unspoiled RPP [

Occurrence and health risk assessment of tropane alkaloids in cereal foods consumed in Korea.

Tropane alkaloids (TA) are natural toxins found in certain plants, including cereals, of which atropine and scopolamine are the main species of concern due to their acute toxicity. This study aimed to determine the occurrence of TA in cereal foods and assess the potential health risks associated with their consumption in Korea. TA levels were analyzed in 80 raw and 71 processed cereal samples, which were distributed throughout Korea in 2021, using ultra-performance liquid chromatography-tandem mass spectrometry. At least one of the six TA species, namely atropine, scopolamine, pseudotropine, tropinone, scopine, and 6-hydroxytropinone, was detected in 10 out of the 151 samples at levels ranging from 0.12 to 88.10 µg kg-1. Dietary exposure (mean, 0.23 ng kg-1 bw day-1) to atropine and scopolamine in the Korean population was estimated to be low across all age groups. This is despite considering worst-case scenarios using the total concentrations of atropine and scopolamine in a millet sample, both of which were detected, and 95th percentile consumption for consumers of millet only. Both the hazard index and margin of exposure methods indicated that the current levels of TA exposure from millet consumption were unlikely to pose significant health risks to the Korean population.

Normal Values of Central, Peripheral, and Root Motor Conduction Times in a Healthy Korean Population.

PURPOSE: Central, peripheral, and root motor conduction times (CMCTs, PMCTs, and RMCTs, respectively) are valuable diagnostic tools for spinal cord and motor nerve root lesions. We investigated the normal values and the effects of age and height on each motor conduction time. METHODS: This study included 190 healthy Korean subjects who underwent magnetic stimulation of the cortex and spinous processes at the C7 and L1 levels. Recording muscles were abductor pollicis brevis and abductor digiti minimi in the unilateral upper limb and extensor digitorum brevis and abductor hallucis in the contralateral lower limb. F-wave and compound motor nerve action potentials were also recorded. Central motor conduction time was evaluated as the difference between cortical motor evoked potential onset latency and PMCT using calculation and spinal stimulation methods. Root motor conduction time was computed as the difference between spinal stimulated and calculated CMCTs. RESULTS: The average age and height of the participants were 41.21 ± 14.39 years and 164.64 ± 8.27 cm, respectively; 39.5% (75/190) patients were men. In the linear regression analyses, upper limb CMCTs showed a significant and weak positive relationship with height. Lower limb CMCTs demonstrated a significant and weak positive relationship with age and height. Peripheral motor conduction times were significantly and positively correlated with age and height. Root motor conduction times showed no significant relationship with age and height, except for abductor pollicis brevis-RMCT, which had a weak negative correlation with height. CONCLUSIONS: This study provides normal values of CMCTs, PMCTs, and RCMTs, which have potential clinical applications. When interpreting CMCTs, age and height should be considered.

Immobilized Candida antarctica lipase B as an sn-1,3 regiospecific biocatalyst for the interesterification of triacylglycerols with fatty acid ethyl esters.

Candida antarctica lipase B (CALB) is regarded as non-regiospecific. This study aimed to investigate the regiospecificity of CALB in the solvent-free interesterification of high-oleic sunflower oil with stearic acid ethyl ester for 1,3-distearoyl-2-oleoylglycerol (SOS)-rich fat preparation using a packed bed reactor. The content ratio of 1,2-distearoyl-3-oleoylglycerol (SSO) to SOS (denoted by SSO/SOS content) obtained using Lipozyme 435 (a commercially immobilized CALB; 0-4.1%), at residence times (1-32 min) was similar to that obtained using Lipozyme RM IM (0-3.0%), but lower than that obtained using Lipozyme TL IM (6.0-39.4%). When immobilized on Lewatit VP OC 1600, Lipozyme CALB had an SSO/SOS content of 0-10.4%, which was greater than that of Palatase 20,000 L (0-1.1%) but was lower than that of Lipozyme TL 100 L (8.8-97.7%). Our findings suggest that immobilized CALB shows distinct sn-1,3 regiospecificity in the interesterification of triacylglycerol with fatty acid ethyl esters.

Lipase-catalyzed preparation of deacidified Buah Merah (Pandanus conoideus) oil.

Buah Merah oil (BMO) is unrefined edible oil containing a high level of free fatty acids (FFA; ∼30% w/w). This study was aimed at preparing deacidified BMO from BMO via lipase-catalyzed esterification of FFA in BMO with added glycerol, using Duolite A568-immobilized Eversa Transform 2.0 (Thermomyces lanuginosus lipase) as biocatalyst. BMO containing 2.4% w/w FFA and 94.6% w/w triacylglycerol was obtained under optimal reaction conditions (temperature, 70°C; FFA-to-glycerol molar ratio, 3:1; enzyme loading based on the protein quantity, 3.75 mg/g BMO, and reaction time, 48 h). No significant difference was found in the contents of ß-carotene, tocopherols, and phytosterols between raw and deacidified BMO. The induction period of oxidation was significantly longer in deacidified BMO (16.37 h) than in raw BMO (0.03 h). These results suggest that deacidified BMO could be enzymatically prepared without the loss of health-beneficial minor components while enhancing the oxidative stability. PRACTICAL APPLICATION: Although BMO has recently received much attention for its potential biological activities, the commercial use of BMO as a healthy oil has been limited due to its high FFA content. Unlike conventional alkali and steam refining, enzymatic deacidification of BMO employed in this study might help the commercialization of BMO, because this procedure enables the improvement of oil yield and the retaining of health-beneficial minor components.

Efficient Synthesis of Stearidonic Acid Enriched Triacylglycerol from Ahiflower Seed Oil via a Two-Step Enzyme Reaction.

Stearidonic acid (SDA) is a plant-based n-3 polyunsaturated fatty acid with multiple biological activities. The enrichment of SDA and synthesis of triacylglycerol (TAG) were carried out consecutively via two lipase-catalyzed reactions, hydrolysis, and esterification. First, SDA was enriched into a glyceride fraction from ahiflower seed oil by Candida rugosa lipase-catalyzed hydrolysis. Under the optimum conditions of 35°C, 0.1% lipase powder of Lipase OF, and 50% buffer solution (based on the weight of total substrate), SDA was enriched from 21.6 to 40.7 wt% in glyceride fraction. SDA-enriched TAG was then synthesized from the SDA-enriched glyceride and the SDA-enriched fatty acid via esterification using an in-house immobilized lipase as a biocatalyst. The SDA-enriched fatty acid was obtained from part of the SDA-enriched glyceride by saponification and the in-house immobilized lipase was prepared from Eversa® Transform 2.0 using Lewatit VP OC 1600 as a carrier. The optimum reaction conditions for the synthesis of TAG were a temperature of 50°C, an enzyme loading of 10%, and a vacuum of 10 mmHg. A maximum conversion to TAG of ca. 94% was achieved after 12 h under the optimum conditions.

Combined analysis of inorganic elements and sugars for the identification of red pepper powder containing undeclared ingredients.

This study sought to identify adulterated red pepper powder (RPP) containing undeclared ingredients, such as salts, glucose, Monascus red pigments, and other plant ingredients (e.g., wheat flour, garlic powder, onion powder) using element and sugar analysis methods. Analytical data were obtained for 66 samples of authentic RPP and 12 samples of adulterated RPP. The variables selected to identify the authenticity of RPP include Na, Cl, K, maltohexaose, and maltoheptaose, which partly or totally originate from RPP, salts, or Monascus red pigments. All the 12 samples of commercial seasoned RPP used as models of adulterated RPP and all the 20 blind samples containing ≥10% (w/w) of commercial seasoned RPP were correctly identified by applying the range of the five variables found for the authentic RPP samples. Our findings suggest that combined analyses of the above five constituents could be used to identify adulterated RPP containing undeclared ingredients. PRACTICAL APPLICATION: Adulteration of high-priced spice products, including red pepper powder (RPP), has increasingly become a public concern worldwide as it endangers consumer health and represents economic fraud. This study provides analytical methods that can accurately determine the authenticity of RPP. They would become effective means for protecting producers and suppliers against unfair competition and consumers against health threats.

Clinical Usefulness of the Korean Version of the Dysphagia Handicap Index: Reliability, Validity, and Role as a Screening Test.

This study aimed to measure the validity and reliability of the Korean version of the Dysphagia Handicap Index (K-DHI) and evaluate its diagnostic efficacy for predicting aspiration. We enrolled 104 patients with dysphagia symptoms (D group) and 88 controls (ND group). Among controls, there were 43 patients without dysphagia symptoms (ND patient group). All subjects completed the K-DHI survey. The D and ND group patients underwent the Gugging Swallowing Screen (GUSS) and videofluoroscopic swallowing study (VFSS). Two weeks later, the D group completed the second session of the K-DHI survey. The internal consistency of the K-DHI was good to excellent (Cronbach's α: 0.79-0.95). The test-retest reliability of the K-DHI survey was also high (interclass correlation coefficient = 0.88). There were moderate correlations between the K-DHI and GUSS (r = - 0.65, p < 0.001) as well as findings of VFSS-videofluoroscopic dysphagia scale (r = 0.55, p < 0.001) and American Speech-Language-Hearing Association National Outcome Measurement System swallowing scale (r = - 0.55, p < 0.001). For predicting aspiration, the K-DHI cutoff value was 11 (sensitivity, 0.82; specificity, 0.72; positive predictive value, 0.34; and negative predictive value, 0.96). K-DHI ≥ 11 [odds ratio (OR), 6.43; 95% Confidence Interval (CI) (1.87-22.16); p = 0.003] and GUSS ≤ 15 [OR 4.73; 95% CI (1.59-14.07); p = 0.005] were independent risk factors for aspiration on VFSS. The K-DHI is a reliable and valid self-reporting instrument for evaluating patient's quality of life associated with dysphagia among the Korean language population. It is also useful for the screening of aspiration.

Distinguishing Korean and Chinese red pepper powder using inductively coupled plasma and X-ray fluorescence-based analysis.

This study aimed to distinguish between Korean and Chinese red pepper powder (RPP) using inorganic elemental analysis data combined with orthogonal partial least squares-discriminant analysis (OPLS-DA). Elemental concentrations were obtained for 31 Korean and 31 Chinese RPP samples that were collected in Korea. Energy dispersive X-ray fluorescence spectroscopy detected 11 elements in these samples. Rb and Cl concentrations were selected as the variables which best allowed distinguishing between Korean and Chinese RPP using an S-plot from OPLS-DA. Rb and Cl concentrations in the Korean RPP samples were ≤ 1.6 mg/100 g (measured by inductively coupled plasma-optical emission spectroscopy) and ≤ 215 mg/100 g, respectively. A blind trial demonstrated that Korean RPP containing ≥ 50 g/100 g of Chinese RPP could be identified by applying predetermined ranges of Rb and Cl concentrations, suggesting that analysis of these two elements is a possible approach to distinguish between Korean and Chinese RPP.

Can Evoked Potential Changes during the Superficial Temporal Artery-Middle Cerebral Artery Bypass Surgery Predict Postoperative Improvement of Cerebral Perfusion and Functional Status?

BACKGROUND: We investigated evoked potential (EP) changes during superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery and their correlations with imaging and clinical findings postoperatively. METHODS: This retrospective study included patients who underwent STA-MCA bypass surgery due to ischemic stroke with large artery occlusion (MB group). Patients who underwent unruptured MCA aneurysm clipping were enrolled in the control group (MC group). Median and tibial somatosensory evoked potentials (SSEP), and motor evoked potentials recorded from the abductor pollicis brevis (APB-MEP) and abductor hallucis (AH-MEP) were measured intraoperatively. Modified Rankin scale (mRS) and perfusion-weighted imaging (PWI) related variables, i.e., mean transit time (MTT) and time to peak (TTP), were assessed. RESULTS: Δmedian SSEP, ΔAPB-MEP, and ΔAH-MEP were significantly higher in the MB group than in the MC group (p = 0.027, p = 0.006, and p = 0.015, respectively). APB-MEP and AH-MEP amplitudes were significantly increased at the final measurement (p = 0.010 and p < 0.001, respectively). The ΔTTP asymmetry index was moderately correlated with ΔAPB-MEP (r = 0.573, p = 0.005) and ΔAH-MEP (r = 0.617, p = 0.002). ΔAPB-MEP was moderately correlated with ΔMTT (r = 0.429, p = 0.047) and ΔmRS at 1 month (r = 0.514, p = 0.015). CONCLUSIONS: MEP improvement during STA-MCA bypass surgery was partially correlated with PWI and mRS and could reflect the recovery in cerebral perfusion.

Application of digital infrared thermography for carpal tunnel syndrome evaluation.

We investigated the thermographic findings of carpal tunnel syndrome (CTS). We enrolled 304 hands with electrodiagnostically identified CTS and 88 control hands. CTS hands were assigned to duration groups (D1, < 3 months; D2, 3‒6 months; D3, 6‒12 months; D4, ≥ 12 months) and severity groups (S1, very mild; S2, mild; S3, moderate; S4, severe). The temperature difference between the median and ulnar nerve territories (ΔM-U territories) decreased as CTS duration and severity increased. Significant differences in ΔM-U territories between the D1 and D3, D1 and D4, D2 and D4, and S1 and S4 groups (P = 0.003, 0.001, 0.001, and < 0.001, respectively) were observed. Thermal anisometry increased as CTS duration and severity increased. Significant differences in thermal anisometry between the D1 and D4 as well as the D2 and D4 groups (P = 0.005 and 0.04, respectively) were noted. Thermal anisometry was higher in the S4 group than in the S1, S2, and S3 groups (P = 0.009, < 0.001, and 0.003, respectively). As CTS progresses, skin temperature tends to decrease and thermal variation tends to increase in the median nerve-innervated area. Thermographic findings reflect the physiological changes of the entrapped median nerve.

Machine learning-based approach for disease severity classification of carpal tunnel syndrome.

Identifying the severity of carpal tunnel syndrome (CTS) is essential to providing appropriate therapeutic interventions. We developed and validated machine-learning (ML) models for classifying CTS severity. Here, 1037 CTS hands with 11 variables each were retrospectively analyzed. CTS was confirmed using electrodiagnosis, and its severity was classified into three grades: mild, moderate, and severe. The dataset was randomly split into a training (70%) and test (30%) set. A total of 507 mild, 276 moderate, and 254 severe CTS hands were included. Extreme gradient boosting (XGB) showed the highest external validation accuracy in the multi-class classification at 76.6% (95% confidence interval [CI] 71.2-81.5). XGB also had an optimal model training accuracy of 76.1%. Random forest (RF) and k-nearest neighbors had the second-highest external validation accuracy of 75.6% (95% CI 70.0-80.5). For the RF and XGB models, the numeric rating scale of pain was the most important variable, and body mass index was the second most important. The one-versus-rest classification yielded improved external validation accuracies for each severity grade compared with the multi-class classification (mild, 83.6%; moderate, 78.8%; severe, 90.9%). The CTS severity classification based on the ML model was validated and is readily applicable to aiding clinical evaluations.

Discriminant Analysis of the Geographical Origin of Asian Red Pepper Powders Using Second-Derivative FT-IR Spectroscopy.

This study aimed to discriminate between the geographical origins of Asian red pepper powders distributed in Korea using Fourier-transform infrared (FT-IR) spectroscopy coupled with multivariate statistical analyses. Second-derivative spectral data were obtained from a total of 105 red pepper powder samples, 86 of which were used for statistical analysis, and the remaining 19 were used for blind testing. A one-way analysis of variance (ANOVA) test confirmed that eight peak variables exhibited significant origin-dependent differences, and the canonical discriminant functions derived from these variables were used to correctly classify all the red pepper powder samples based on their origins. The applicability of the canonical discriminant functions was examined by performing a blind test wherein the origins of 19 new red pepper powder samples were correctly classified. For simplicity, the four most significant variables were selected as discriminant indicator variables, and the applicable range for each indicator variable was set for each geographical origin. By applying the indicator variable ranges, the origins of the red pepper powders of all the statistical and blind samples were correctly identified. The study findings indicate the feasibility of using FT-IR spectroscopy in combination with multivariate analysis for identifying the geographical origins of red pepper powders.

Preparation of Low-Diacylglycerol Cocoa Butter Equivalents by Hexane Fractionation of Palm Stearin and Shea Butter.

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.

Electrodiagnostic, Sonographic, and Clinical Features of Carpal Tunnel Syndrome with Bifid Median Nerve.

PURPOSE: A bifid median nerve (BMN) is not a rare variant. This study aimed to investigate the features of carpal tunnel syndrome (CTS) accompanied by BMN. PATIENTS AND METHODS: In this retrospective study, we defined a BMN group as CTS with BMN and a non-bifid median nerve (NMN) group as CTS without BMN. All hands were assigned to four severity grades according to the findings of electrodiagnosis (EDx): very mild, mild, moderate, and severe. The cross-sectional area (CSA) of the median nerve, palmar bowing of the flexor retinaculum, and persistent median artery (PMA) were assessed by ultrasonography. Numerical pain rating scale (NRS) and symptom duration were assessed as clinical variables. RESULTS: Sixty-four hands (57 patients) and 442 hands (341 patients) were enrolled in the BMN and the NMN groups, respectively. BMN was prevalent in 12.6% of all CTS hands. The distribution of EDx severity grade was milder in the BMN group than in the NMN group (P<0.001). The CSA of the BMN group was 16.2±4.1 mm2, slightly larger than 15.1±4.2 mm2 in the NMN group (P=0.056). The BMN group showed higher NRS than the NMN group (5.5±1.5 and 4.4±1.7, respectively; P<0.001). In the subgroup analysis, NRS was significantly higher in the BMN group than in the NMN group at all EDx severity grades. In the BMN group, the PMA group showed greater EDx severity (P=0.037) and higher NRS (6.0 and 5.0, respectively; P=0.012) than the non-PMA group. The radial side branch's CSA was larger than that of the ulnar side branch (10.0 mm2 and 6.0 mm2, respectively; P<0.001). CONCLUSION: CTS with BMN presented more severe symptoms and relatively milder EDx severity. When assessing the severity of CTS with BMN, the clinical symptoms should primarily be considered, as well as we should complementarily evaluate the EDx and ultrasonography.

Usefulness of Intraoperative Neurophysiological Monitoring During the Clipping of Unruptured Intracranial Aneurysm: Diagnostic Efficacy and Detailed Protocol.

Background: Intraoperative neurophysiological monitoring (IONM) has been widely applied in brain vascular surgeries to reduce postoperative neurologic deficit (PND). This study aimed to investigate the effect of IONM during clipping of unruptured intracranial aneurysms (UIAs). Methods: Between January 2013 and August 2020, we enrolled 193 patients with 202 UIAs in the N group (clipping without IONM) and 319 patients with 343 UIAs in the M group (clipping with IONM). Patients in the M group were intraoperatively monitored for motor evoked potentials (MEPs) and somatosensory evoked potentials (SSEPs). Irreversible evoked potential (EP) change was defined as EP deterioration that did not recover until surgery completion. Sustained PND was defined as neurological symptoms lasting for more than one postoperative month. Results: Ten (3.1%) and 13 (6.7%) in the M and N groups, respectively, presented with PND. Compared with the N group, the M group had significantly lower occurrence rates of sustained PND [odds ratio (OR) = 0.36, 95% confidence interval (CI) = 0.13-0.98, p = 0.04], ischemic complications (OR = 0.39, 95% CI = 0.15-0.98, p = 0.04), and radiologic complications (OR = 0.40, 95% CI = 0.19-0.82, p = 0.01). Temporary clipping was an independent risk factor for ischemic complications (ICs) in the total patient group (OR = 6.18, 95% CI = 1.75-21.83, p = 0.005), but not in the M group (OR = 5.53, 95% CI = 0.76-41.92, p = 0.09). Regarding PND prediction, considering any EP changes (MEP and/or SSEP) showed the best diagnostic efficiency with a sensitivity of 0.900, specificity of 0.940, positive predictive value of 0.321, negative predictive value (NPV) of 0.997, and a negative likelihood ratio (LR) of 0.11. Conclusion: IONM application during UIA clipping can reduce PND and radiological complications. The diagnostic effectiveness of IONM, specifically the NPV and LR negative values, was optimal upon consideration of changes in any EP modality.

Diagnostic Role of Flexion-extension Central Motor Conduction Time in Cervical Spondylotic Myelopathy.

STUDY DESIGN: Retrospective study. OBJECTIVE: The purpose of this study was to assess the diagnostic usefulness of flexion-extension central motor conduction time(CMCT) for patients with cervical spondylotic myelopathy (CSM). SUMMARY OF BACKGROUND DATA: Previous reports have suggested that cervical cord compression can be aggravated by neck motions. Thus, the importance of dynamic magnetic resonance imaging (MRI) has been emphasized. However, authors of this study found no reports conducted at the time of this research on whether flexion-extension CMCT was useful for detecting myelopathy. METHODS: We enrolled 227 patients with CSM for this study. We acquired CMCT recorded from the abductor pollicis brevis muscle. All patients underwent a dynamic CMCT study during neck flexion and extension as well as a static study during neutral neck. Static and dynamic MRIs were also scanned. We read all MR images using Muhle classification (MC). RESULTS: CMCT was significantly delayed with flexion (P < 0.01) and extension (P < 0.01) compared to neutral neck position. Patients with MC grade 1 and 2 showed significant lag in CMCT during flexion and extension. No significant lag by neck motion was observed for those in the MC grade 3. We also evaluated the amount of CMCT variation according to MC grade change (G0, G1, G2) by neck motion. Delta-CMCT of both G1 and G2 were significantly larger than those of G0 in both flexion and extension. In neutral neck, the CMCT showed significant difference between MC grades 1 and 3. They also displayed significant delay with delay with high signal intensity on T2 MRI. More than one-third of the patients whose CMCT was within normal range in neutral neck presented abnormal CMCT in neck flexion (35.3%) and extension (37.8%). CONCLUSION: CMCT is significantly slower in both neck flexion and neck extension than in the neutral neck position. These findings reflect the dynamic cervical cord impingement.Level of Evidence: 4.