A135 ENDOSCOPIC SUBMUCOSAL DISSECTION OF GASTRIC ADENOMAS AND EARLY CARCINOMAS

Background

Management of gastric adenoma and early gastric cancer requires endoscopic resection. This can often be achieved with endoscopic mucosal resection (EMR), which has been shown to be effective with a good safety profile. One disadvantage of EMR is that it is often completed piecemeal, leading to indeterminant margins and higher rates of recurrences that require additional intervention. Endoscopic submucosal dissection (ESD) is a more advanced endoscopic resection technique that has been shown to be more effective than EMR at en-bloc resection. ESD requires high technical proficiency but it is becoming more widely available in western countries.

Purpose

The purpose of this study is to report on the outcomes and rates of complications of gastric ESD completed in a tertiary centre in British Columbia.

Method

All gastric ESD was completed by a senior therapeutic endoscopist who has previously received training in Japan. Retrospective data were collected on all gastric ESD procedures done in St. Paul’s Hospital from May 7th, 2015, when the procedure first became available, to Aug 30th, 2022. Inclusion criteria were all adults who have undergone ESD for resection of a gastric lesion. Exclusion criteria were patients younger than 18. Data collected included demographic variables, polyp characteristics, procedural outcomes, and complications.

Result(s)

A total of 49 ESD procedures were completed. The mean size of the resected lesions was 25.3 mm (range: 5 – 100 mm). Technical success, defined as successful resection of all polypoid tissue, was achieved in 48/49 procedures (98.0%). En bloc resection was achieved in 42/48 (87.5%) completed ESD. The rate of R0 resection was also 42/48 (87.5%). Curative resection, defined as technically successful ESD with an R0 margin and no lymphovascular invasion, was achieved in 41/49 (83.7%) of the cases. In our cohort, 8 patients had adenocarcinoma, 5 of which had a curative resection with no evidence of recurrence. None of the ESD resulted in any intra-procedural or delayed perforation. 5/49 (10.2%) patients had clinically significant post-endoscopic resection bleeding. Out of 37 patients that completed follow-up, 3 (8.1%) had recurrence, and all of them were managed endoscopically. 4/49 (8.2%) of patients required surgery post-ESD.

Conclusion(s)

In our cohort, ESD is an effective endoscopic resection modality for gastric lesions with a high rate of technical success and curative resection. Despite a deeper plane of resection versus other endoscopic resection modalities, its complication rate remains low. Although ESD requires high technical proficiency, its favorable outcomes along with low rates of complication make ESD highly feasible for the resection of gastric lesions. Further research will be needed to study the implementation and outcomes of

ESD in a western setting.

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Disclosure of Interest

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A131 ENDOSCOPIC SUBMUCOSAL DISSECTION OF COLORECTAL ADENOMAS AND EARLY ADENOCARCINOMAS: OUTCOMES FROM BRITISH COLUMBIA

Background

Endoscopic resection is the standard of care for the management of colorectal polyps. Larger and more complex polyps require endoscopic mucosal resection (EMR). While complications have been low, EMR is often piecemeal, resulting in indeterminant margins and often a higher recurrence rate. Endoscopic submucosal dissection (ESD) is an advanced endoscopic resection technique with a higher rate of en bloc resection. While more data exist for the resection of gastric lesions with ESD, ESD is becoming more widely used in western countries for the resection of colorectal lesions.

Purpose

The purpose of this study is to report on the outcomes and rates of complications for colorectal ESD completed in a tertiary centre in British Columbia.

Method

All colorectal ESD was completed by a senior therapeutic endoscopist who has previously received training in Japan. Retrospective data were collected on all colorectal ESD procedures done in St. Paul’s Hospital from July 11th, 2016, when the procedure first became available, to Aug 30th, 2022. Inclusion criteria were all adults who have undergone ESD for resection of a colorectal lesion. Exclusion criteria were patients younger than 18. Data collected included demographic variables, polyp characteristics, procedural outcomes, and complications.

Result(s)

A total of 39 ESD procedures were completed. The mean size of the resected lesion was 30.4 mm (range: 5 – 60 mm). Technical success, defined as successful resection of all polypoid tissue, was achieved in 35/39 procedures (89.7%). En-bloc resection was achieved in 27/35 (77.1%) of the completed ESD. The rate of R0 resection was 22/35 (62.9%). Curative resection, defined as technically successful ESD with R0 margin and no lymphovascular invasion, was achieved in 23/39 (59.0%) of the cases and the majority of the patients with non-curative resection that underwent endoscopic surveillance had no recurrence on follow-up. In our cohort, 3/39 (7.7%) patients had adenocarcinoma. None of the ESD resulted in any intra-procedural or delayed perforation. 3/39 (7.7%) patients had clinically significant post-endoscopic resection bleeding. Out of 24 patients that completed follow-up, 4 (16.7%) had recurrence at the resection site that was managed endoscopically. 4/39 (10.3%) of patients required surgery post-ESD.

Conclusion(s)

In our cohort, ESD is an effective endoscopic resection modality for the management of colorectal adenomas and early adenocarcinoma with a high rate of technical success and low rates of complications. Although the rate of curative resection was low, most were the result of R1 or Rx resection and a majority of the follow-ups in this subgroup demonstrated no further recurrence. The rate of en bloc resection is high, especially given the average size of adenomas in this cohort. Although ESD requires high technical proficiency, its favorable outcomes and low complication rates make ESD highly feasible for the resection of colorectal lesions.

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Disclosure of Interest

None Declared

Risk factors for delirium among patients with advanced cancer in palliative care: a multicenter, patient-based registry cohort in South Korea

OBJECTIVE

Previous studies have comprehensively investigated the prevalence and various potential risk factors for delirium among patients with advanced cancer admitted to the acute palliative care unit (APCU). Our objective was to evaluate the comprehensive association between delirium and various risk factors among patients with advanced cancer in an acute palliative care setting using a patient-based multicenter registry cohort.

PATIENTS AND METHODS

We performed a multicenter, patient-based registry cohort study collected in South Korea between January 1, 2019, and December 31, 2020. Delirium was identified using a medical record review based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.

RESULTS

In total, 2,124 eligible patients with advanced cancer in the APCU met the inclusion criteria. There were 127 out of 2,124 patients (prevalence, 6.0%; 95% CI, 5.0 to 7.1) with delirium during admission. Delirium in patients with advanced cancer was associated with age >70 years (OR, 1.793; 95% CI, 1.246 to 2.581), male sex (OR, 1.675; 95% CI, 1.131 to 2.479), no chemotherapy during hospitalization (OR, 2.019; 95% CI, 1.236 to 3.298), hearing impairment (OR, 3.566; 95% CI, 1.176 to 10.810), underweight (OR, 1.826; 95% CI, 1.067 to 3.124), current use of opioid medication (OR, 1.942; 95% CI, 1.264 to 2.982), previous history of delirium (OR, 12.497; 95% CI, 6.920 to 22.568), and mental illness (OR, 2.333; 95% CI, 1.251 to 4.352).

CONCLUSIONS

In a large-scale multicenter patient-based registry cohort, delirium was associated with old age, male sex, no chemotherapy during hospitalization, hearing impairment, underweight, current use of opioid medication, and a history of delirium and mental illness. Our findings suggest physicians should pay attention to delirium in patients with advanced cancer admitted to the APCU with the above risk factors.

Measurement of extracellular volume fraction using magnetic resonance-based conductivity tensor imaging

Conductivity tensor imaging (CTI) using MRI is an advanced method that can non-invasively measure the electrical properties of living tissues. The contrast of CTI is based on underlying hypothesis about the proportionality between the mobility and diffusivity of ions and water molecules inside tissues. The experimental validation of CTI in both in vitro and in vivo settings is required as a reliable tool to assess tissue conditions. The changes in extracellular space can be indicators for disease progression, such as fibrosis, edema, and cell swelling. In this study, we conducted a phantom imaging experiment to test the feasibility of CTI for measuring the extracellular volume fraction in biological tissue. To mimic tissue conditions with different extracellular volume fractions, four chambers of giant vesicle suspension (GVS) with different vesicle densities were included in the phantom. The reconstructed CTI images of the phantom were compared with the separately-measured conductivity spectra of the four chambers using an impedance analyzer. Moreover, the values of the estimated extracellular volume fraction in each chamber were compared with those measured by a spectrophotometer. As the vesicle density increased, we found that the extracellular volume fraction, extracellular diffusion coefficient, and low-frequency conductivity decreased, while the intracellular diffusion coefficient slightly increased. On the other hand, the high-frequency conductivity could not clearly distinguish the four chambers. The extracellular volume fraction measured by the spectrophotometer and CTI method in each chamber were quite comparable, i.e., (1.00, 0.98 ± 0.01), (0.59, 0.63 ± 0.02), (0.40, 0.40 ± 0.05), and (0.16, 0.18 ± 0.02). The prominent factor influencing the low-frequency conductivity at different GVS densities was the extracellular volume fraction. Further studies are needed to validate the CTI method as a tool to measure the extracellular volume fractions in living tissues with different intracellular and extracellular compartments.

A novel cardiac arrest severity score for the early prediction of hypoxic-ischemic brain injury and in-hospital death

Funding Acknowledgements

Type of funding sources: None.

Background

Out-of-hospital cardiac arrest (OHCA) outcomes are unsatisfactory despite postcardiac arrest care. Early prediction of prognoses might help stratify patients and provide tailored therapy.

Purpose

In this study, we derived and validated a novel scoring system to predict hypoxic-ischaemic brain injury (HIBI) and in-hospital death (IHD).

Methods

We retrospectively analysed Korean Hypothermia Network prospective registry data collected from in Korea between 2015 and 2018. Patients without neuroprognostication data were excluded, and the remaining patients were randomly divided into derivation and validation cohorts. HIBI was defined when at least one prognostication predicted a poor outcome. IHD meant all deaths regardless of cause. In the derivation cohort, stepwise multivariate logistic regression was conducted for HIBI and IHD scores, and model performance was assessed. We then classified patients into four categories and analysed associations between the categories and cerebral performance categories (CPCs) at hospital discharge. Finally, we validated our models in the internal validation cohort.

Results

Among 1373 patients, 240 were excluded, and 1133 were randomised into derivation (n=754) and validation cohorts (n=379). In the derivation cohort, 7 and 8 predictors were selected for HIBI (0–8) and IHD scores (0–11), respectively, and the area under the curve (AUC) was 0.85 (95% CI 0.82–0.87) and 0.80 (95% CI 0.77–0.82), respectively. Applying optimum cutoff values of ≥6 points for HIBI and ≥7 points for IHD, patients were classified as follows: HIBI (-)/IHD (-), Category 1 (n=424); HIBI (-)/IHD (+), Category 2 (n=100); HIBI (+)/IHD (-), Category 3 (n=21); and HIBI (+)/IHD (+), Category 4 (n=209). CPCs at discharge were significantly different in each category (p<0.001). In the validation cohort, the model showed moderate discrimination (AUC 0.83, 95% CI 0.79–0.87 for HIBI and AUC 0.77, 95% CI 0.72–0.81 for IHD) with good calibration. Each category of the validation cohort showed a significant difference in discharge outcomes (p<0.001) and a similar trend to the derivation cohort.

Conclusions

We presented a novel approach for assessing illness severity after OHCA. Although external prospective studies are warranted, risk stratification for HIBI and IHD could help provide OHCA patients with appropriate treatment.

Association between Fiber Intake and Risk of Incident Chronic Kidney Disease: The UK Biobank Study

OBJECTIVES

Dietary fiber intake is associated with a lower risk of diabetes, cardiovascular disease, and cancer. However, it is unknown whether dietary fiber has a beneficial effect on preventing the development of chronic kidney disease (CKD).

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

Using the UK Biobank prospective cohort, 110,412 participants who completed at least one dietary questionnaire and had an estimated glomerular filtration rate ≥60 mL/min/1.73 m2, urinary albumin-to-creatinine ratio <30 mg/g, and no history of CKD were included. The primary exposure was total dietary fiber density, calculated by dividing the absolute amount of daily total fiber intake by total energy intake (g/1,000 kcal). We separately examined soluble and insoluble fiber densities as additional predictors. The primary outcome was incident CKD based on diagnosis codes.

RESULTS

A total of 3,507 (3.2%) participants developed incident CKD during a median follow-up of 9.9 years. In a multivariable cause-specific model, the adjusted hazard ratios (aHRs; 95% confidence intervals [CIs]) for incident CKD were 0.85 (0.77-0.94), 0.78 (0.70-0.86), and 0.76 (0.68-0.86), respectively, for the second, third, and highest quartiles of dietary fiber density (reference: lowest quartile). In a continuous model, the aHR for each +∆1.0g/1,000 kcal increase in dietary fiber density was 0.97 (95% CI, 0.95-0.99). This pattern of associations was similar for both soluble and insoluble fiber densities and did not differ across subgroups of sex, age, body mass index, hypertension, diabetes, smoking, and inflammation.

CONCLUSION

Increased fiber intake was associated with a lower risk of CKD in this large well-characterized cohort.

Measurement of extracellular volume fraction using magnetic resonance-based conductivity tensor imaging

Conductivity tensor imaging (CTI) using MRI is an advanced method that can non-invasively measure the electrical properties of living tissues. The contrast of CTI is based on underlying hypothesis about the proportionality between the mobility and diffusivity of ions and water molecules inside tissues. The experimental validation of CTI in both in vitro and in vivo settings is required as a reliable tool to assess tissue conditions. The changes in extracellular space can be indicators for disease progression, such as fibrosis, edema, and cell swelling. In this study, we conducted a phantom imaging experiment to test the feasibility of CTI for measuring the extracellular volume fraction in biological tissue. To mimic tissue conditions with different extracellular volume fractions, four chambers of giant vesicle suspension (GVS) with different vesicle densities were included in the phantom. The reconstructed CTI images of the phantom were compared with the separately-measured conductivity spectra of the four chambers using an impedance analyzer. Moreover, the values of the estimated extracellular volume fraction in each chamber were compared with those measured by a spectrophotometer. As the vesicle density increased, we found that the extracellular volume fraction, extracellular diffusion coefficient, and low-frequency conductivity decreased, while the intracellular diffusion coefficient slightly increased. On the other hand, the high-frequency conductivity could not clearly distinguish the four chambers. The extracellular volume fraction measured by the spectrophotometer and CTI method in each chamber were quite comparable, i.e., (1.00, 0.98 ± 0.01), (0.59, 0.63 ± 0.02), (0.40, 0.40 ± 0.05), and (0.16, 0.18 ± 0.02). The prominent factor influencing the low-frequency conductivity at different GVS densities was the extracellular volume fraction. Further studies are needed to validate the CTI method as a tool to measure the extracellular volume fractions in living tissues with different intracellular and extracellular compartments.

Effects of Irradiation on Brain Tumors Using MR-Based Electrical Conductivity Imaging

Ionizing radiation delivers sufficient energy inside the human body to create ions, which kills cancerous tissues either by damaging the DNA directly or by creating charged particles that can damage the DNA. Recent magnetic resonance (MR)-based conductivity imaging shows higher sensitivity than other MR techniques for evaluating the responses of normal tissues immediately after irradiation. However, it is still necessary to verify the responses of cancer tissues to irradiation by conductivity imaging for it to become a reliable tool in evaluating therapeutic effects in clinical practice. In this study, we applied MR-based conductivity imaging to mouse brain tumors to evaluate the responses in irradiated and non-irradiated tissues during the peri-irradiation period. Absolute conductivities of brain tissues were measured to quantify the irradiation effects, and the percentage changes were determined to estimate the degree of response. The conductivity of brain tissues with irradiation was higher than that without irradiation for all tissue types. The percentage changes of tumor tissues with irradiation were clearly different than those without irradiation. The measured conductivity and percentage changes between tumor rims and cores to irradiation were clearly distinguished. The contrast of the conductivity images following irradiation may reflect the response to the changes in cellularity and the amounts of electrolytes in tumor tissues.

Regional Analysis of Liver Surface Nodularity in a Single Axial MR Image for Staging Liver Fibrosis

BACKGROUND

The assessment of liver surface nodularity (LSN) for staging hepatic fibrosis is restricted in clinical practice because it requires customized software and time-consuming procedures. A simplified method to estimate LSN score may be useful in the clinic.

PURPOSE

To evaluate the regional analysis of LSN and processing time in a single axial liver MR image for staging liver fibrosis.

STUDY TYPE

Retrospective.

POPULATION

A total of 210 subjects, a multicenter study.

FIELD STRENGTH/SEQUENCE

A 3 T/noncontrast gradient echo T1WI.

ASSESSMENT

Subjects were divided into five fibrosis groups (F₀  = 29; F₁  = 20; F₂  = 32; F₃  = 50; F₄  = 79) based on the METAVIR fibrosis scoring system. The mean LSN (on three slices) and regional LSN (on one slice) measurements, and the processing times, are compared. The regional LSN scores in five regions-of-interests (ROI_1-5 ) were analyzed in a single axial MRI at the level of the hilum by two independent observers.

STATISTICAL TESTS

Regional variations in LSN scores were compared using ANOVA with Tukey test. Agreement between the mean and regional LSN measurements was evaluated using Pearson correlation coefficients (r) and Bland-Altman plots. The diagnostic performance of mean and regional LSN scores according to fibrosis stage was evaluated with the AUROC. A P value < 0.05 was considered statistically significant.

RESULTS

Total processing time for a regional LSN measurement (3.6 min) was 75.5% less than that for mean LSN measurement (14.7 min). Mean LSN scores and all five regional LSN scores showed significant differences between fibrosis groups. Among regional LSN scores, ROI₅ showed the highest AUROC (0.871 at cut-off 1.12) for discriminating F_0-2 vs. F_3-4 and the best correlation with mean LSN score (r = 0.800, -0.07 limit of agreement).

CONCLUSION

Quantitative regional LSN measurement in a single axial MR image reduces processing time. Regional ROI₅ LSN score might be useful for clinical decision-making and for distinguishing the difference between early fibrosis (F_0-2 ) and advanced fibrosis (F_3-4 ) in the liver.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Minimum standards of pelvic exenterative practice: PelvEx Collaborative guideline

This document outlines the important aspects of caring for patients who have been diagnosed with advanced pelvic cancer. It is primarily aimed at those who are establishing a service that adequately caters to this patient group. The relevant literature has been summarized and an attempt made to simplify the approach to management of these complex cases.

Prognostic impact of plasma glucose on cardiogenic shock patients with or without diabetes ellitus: smart rescue trial

Background

Even though the presence of hyperglycemia has shown to affect the clinical outcome of cardiogenic shock patients, the extent of hyperglycemia and its association with prognosis have not been fully addressed in large population

Purpose

Investigate the clinical relationship between hyperglycemic status and in-hospital mortality in cardiogenic shock patients

Method

A total of 1,177 consecutive cardiogenic shock patients were enrolled from January 2014 to December of 2018 at 12 hospitals in South Korea. The primary outcome was in-hospital mortality. Patients were divided into four groups according to their initial plasma glucose level in each of diabetes patients (n=752) and non-diabetes patients (n=425); group 1 (≤8 mmol/L), group 2 (8–12 mmol/L), group 3 (12–16 mmol/L) and group 4 (≥16 mmol/L).

Results

The groups with higher admission plasma glucose were associated with lower systolic blood pressure and higher lactic acid level in both diabetic and non-diabetic patients. In-hospital mortality increased in groups with higher admission plasma glucose level in non-diabetic patients (group-1:24.2%, group-2: 28.6%, group-3: 38.1%, group-4: 49.0%, p&lt;0.01) whereas in diabetic patients, mortality and admission plasma glucose level showed no significant association (group-1: 45%, group-2: 35.4%, group-3: 33.3%, group-4: 43.1%, p=0.26). Even after Multivariate analysis, high plasma glucose was an independent predictor of in-hospital mortality in non-diabetic patients

Conclusion

In cardiogenic shock patients, plasma glucose obtained at admission was associated with in-hospital mortality in non-diabetic patients

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): Inha University hospital

Impact of obesity paradox between genders on in-hospital mortality in cardiogenic shock: a retrospective cohort study

Background

In a few studies, obesity was associated with better outcomes in patients with cardiogenic shock (CS). Although this phenomenon, the “obesity paradox”, reportedly manifests differently based on sex in other disease entities, it has not yet been investigated in CS patients.

Methods and results

1,227 patients with CS from The REtrospective and prospective observational Study to investigate Clinical oUtcomes and Efficacy of left ventricular assist device for Korean patients with cardiogenic shock (RESCUE) registry in Korea were analyzed. The study population was classified into obese and non-obese groups according to Asian-Pacific criteria (BMI &gt;25.0 kg/m2 for obese). Clinical impact of obesity on in-hospital mortality according to sex was analyzed using logistic regression analysis and restricted cubic spline curves. In-hospital mortality rate was significantly lower in obese men than non-obese men (34.2% vs. 24.1%, p=0.004) while the difference was not significant in women (37.3% vs. 35.8%, p=0.884). As a continuous variable, higher BMI showed a protective effect in men conversely, BMI was not associated with clinical outcomes in women. Comparing to normal-weight patients, obesity was associated with a decreased risk of in-hospital death in men (multivariable-adjusted OR 0.63, CI 0.43–0.92, p=0.016), not in women (multivariable-adjusted OR 0.94, 95% CI 0.55–1.61, p=0.828). Interaction P value for the association between BMI and sex was 0.023.

Conclusions

Obesity paradox exists and apparently occurs in men among CS patients. The differential effect of BMI on in-hospital mortality was observed according to sex.

Funding Acknowledgement

Type of funding sources: None.

Effects of Sodium Nitroprusside Administered Via a Subdural Intracranial Catheter on the Microcirculation, Oxygenation, and Electrocortical Activity of the Cerebral Cortex in a Pig Cardiac Arrest Model

Background

Postischemic cerebral hypoperfusion has been indicated as an important contributing factor to secondary cerebral injury after cardiac arrest. We evaluated the effects of sodium nitroprusside administered via a subdural intracranial catheter on the microcirculation, oxygenation, and electrocortical activity of the cerebral cortex in the early postresuscitation period using a pig model of cardiac arrest.

Methods and Results

Twenty‐nine pigs were resuscitated with closed cardiopulmonary resuscitation after 14 minutes of untreated ventricular fibrillation. Thirty minutes after restoration of spontaneous circulation, 24 pigs randomly received either 4 mg of sodium nitroprusside (IT‐SNP group) or saline placebo (IT‐saline group) via subdural intracranial catheters and were observed for 5 hours. The same dose of sodium nitroprusside was administered intravenously in another 5 pigs. Compared with the IT‐saline group, the IT‐SNP group had larger areas under the curve for tissue oxygen tension and percent changes of arteriole diameter and number of perfused microvessels from baseline (all P<0.05) monitored on the cerebral cortex during the 5‐hour period, without severe hemodynamic instability. This group also showed faster recovery of electrocortical activity measured using amplitude‐integrated electroencephalography. Repeated‐measures analysis of variance revealed significant group–time interactions for these parameters. Intravenously administered sodium nitroprusside caused profound hypotension but did not appear to increase the cerebral parameters.

Conclusions

Sodium nitroprusside administered via a subdural intracranial catheter increased post–restoration of spontaneous circulation cerebral cortical microcirculation and oxygenation and hastened electrocortical activity recovery in a pig model of cardiac arrest. Further studies are required to determine its impact on the long‐term neurologic outcomes.

Heterointerface Effect on Two-Step Nucleation Mechanism of Bi Particles

The nucleation and crystallization of Bi particles on two matrices, crystalline bismuth sulfide (c-Bi₂S₃) and amorphized bismuth titanium oxide (a-Bi₁₂TiO₂₀), were studied by using in situ transmission electron microscopy (TEM) analysis. The atomic structures of the Bi particles were monitored by acquiring high-resolution TEM images in real time. The Bi particles were grown on c-Bi₂S₃ and a-Bi₁₂TiO₂₀ via a two-step nucleation mechanism; dense liquid clusters were clearly observed at the initial stage of nucleation, and the coalescence of clusters was frequently observed during the growth. However, the nucleation and crystallization behaviors of Bi particles were governed by the matrix; in particular, the evolution of their morphology and atomic structure was confined on c-Bi₂S₃ but free from matrix effects on a-Bi₁₂TiO₂₀. The matrix effect on the two-step nucleation mechanism was demonstrated from a thermodynamic point of view.

Factors associated with treatment escalation among MS specialists and general neurologists: Results from an International cojoint study

BACKGROUND

Previous studies in multiple sclerosis (MS) showed that therapeutic inertia (TI) affects 60-90% of neurologists and up to 25% of daily treatment decisions. The objective of this study was to determine the most common factors and attribute levels associated with decisions to treatment escalation in an international study in MS care.

METHODS

300 neurologists with MS expertise from 20 countries were invited to participate. Participants were presented with 12 pairs of simulated MS patient profiles described by 13 clinically relevant factors. We used disaggregated discrete choice experiments to estimate the weight of factors and attributes affecting physicians' decisions when considering treatment selection. Participants were asked to select the ideal candidate for treatment escalation from modest to higher-efficacy therapies.

RESULTS

Overall, 229 neurologists completed the study (completion rate: 76.3%). The top 3 weighted factors associated with treatment escalation were: previous relapses (20%), baseline expanded disability status scale [EDSS] (18%), and MRI activity (13%). Patient demographics and desire for pregnancy had a modest influence (≤ 3%). We observed differences in the weight of factors associated with treatment escalation between MS specialists and non-MS specialists.

CONCLUSIONS

Our results provide critical information on factors influencing neurologists' treatment decisions and should be applied to continuing medical education strategies.

Associations between changing patterns of ST-T waves morphologies in rest electrocardiography and cardiovascular risk in an asymptomatic low risk population: a report from Ansan-Ansung cohort study

Background

While clinical significance of ST-T wave abnormalities (STA) in rest electrocardiography (ECG) on long-term cardiovascular outcomes has been on debate, few studies have been reported on the association between the changes in ST-T waves in rest ECG and cardiovascular outcomes in low risk populations. We investigate the changing patterns of STA in rest ECG and the predictive value of the changes in ST-T wave in rest ECG for cardiovascular events in an asymptomatic general population.

Methods

A longitudinal community-based cohort study was conducted for 12 years. Koreans aged 40–69 years were followed biennially through scheduled revisit for comprehensive assessments. Among 10,030 participants, 6,648 participants who did not have any cardiovascular diseases, angina-related symptoms or pathologic Q waves in rest ECG at baseline were included for analysis. Changes in STAs were defined using the changes between ECG at baseline and that at the first revisit. A major adverse cardiovascular events was defined as a composite of cardiac death, myocardial infarction, clinical diagnosis of coronary artery disease and stroke.

Results

Among 5,924 participants without STA at baseline, only 187 participants (3.2%) developed new STA. Among 724 patients (10.9%) with STA at baseline, 274 patients (37.8%) persistently showed STA at the first revisit. MACEs occurred more frequently in the participants persistently with STA and those with newly-developed STA than in the participants persistently without STA (Figure 1). Multivariate Cox-proportional hazard models showed that a higher risk of MACE was only associated with the persisted STA (HR 1.69; 95% CI 1.10–2.63). In participants with baseline STA, persisted T-wave flattening was associated with a higher risk of MACE, whereas T-wave inversion, either persisted or fluctuated was not associated with a higher risk of MACE, compared with persistent absence of STA (Figure 2). In the participants without baseline STAs, multivariate Cox-proportional hazard model showed that newly-developed T-wave flattening (HR 1.85; 95% CI 0.20–2.84), not T-wave inversion (HR 1.50; 95% CI 0.85–2.65) was associated with a higher risk of MACE. Survival receiver operating curve analysis showed that the changes in STAs had a C-index of 0.538 (95% CI 0.511–0.558), a sensitivity of 13.0% and a specificity of 92.5% and add only a small value to the predictive power of 10-year atherosclerotic cardiovascular diseases risk estimator (C-index without STA changes 0.708 [0.681–0.736] vs. C-index with STA changes 0.721 [0.694–0.748]).

Conclusions

STAs uncommonly developed while frequently disappeared spontaneously in the asymptomatic general population. Persisted STA and newly developed STA in rest ECG were predictive of future cardiovascular events in the asymptomatic general population. However, the changes in STAs did not significantly improve the predictive value of the conventional risk estimator, when added.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research Foundation of Korea Figure 1Figure 2

Simulation and validation for count-based binary decision of target blood pressure achievement in home blood pressure monitoring data analysis for clinical practice

Introduction

Home blood pressure monitoring (HBPM) is a useful tool to identify hypertension and to decide whether a patient's blood pressure (BP) is controlled. The use of automatized oscillometric BP measurement devices has become increasingly popular with help of information technology and internet of things to the devices. However, applying HBPM to daily clinical practices is still challenging, because most patients with hypertension are in age groups not familiar to digital devices and internet and high BP criteria using average home BP values are often useless in outpatient clinics without easily accessible average BP calculation tools. Therefore, we developed a simple and straightforward method to interpret HBPM through counts of BP ≥135/85 mmHg.

Methods

We simulated 400 cases of HBPM using a random number generator function in statistical software. The simulated average home systolic BP (SBP) and its standard deviation (SD) were 125±15 mmHg and 12±5 mmHg and the number of HBP readings was 24 times. The simulated diastolic BP (DBP) was randomly selected to 50–75% of the SBP. The validation of the binary interpretation method was conducted using actual HBPM data from 386 subjects in a rural area of South Korea. Receiver operating characteristics curve analysis was conducted, and linear regression and logarithmic models were fitted between the numbers of home BP ≥135/85 mmHg and mean BP. Hypertension was defined with average home BP ≥135/85 mmHg.

Results

In the simulated cohort, hypertension was presented in 197 cases (49.3%). The C-index of the numbers of BP readings ≥135/85 mmHg was 0.994 (95% confidence interval [CI] 0.990–0.998), and ≥12 of 24 BP readings ≥135/85 mmHg showed a sensitivity of 95.4%, a specificity of 95.1% and an accuracy of 95.3% for the diagnosis of hypertension. In validation cohort, the numbers of home BP measurements varied from 8 to 81 times. The validation cohort similarly showed that the C-index of the ratio between the number of high BP readings (≥135/85 mmHg) to the number of BP measurements (R-NHBP/NBP) was 0.985 (95% CI, 0.976–0.994) and the best accuracy was shown at R-NHBP/NBP of ≥0.45. R-NHBP/NBP of ≥0.5 showed a sensitivity of 0.957, a specificity of 0.907 and an accuracy of 0.927. The accuracy of the R-NHBP/NBP of ≥0.5 decreased as SD and the range of SBP increased, whereas it did not change with the number of measurements (Figure 1). R-NHBP/NBP &lt;0.2 predicted normotension and R-NHBP/NBP &gt;0.8 predicted hypertension in 95% confidence. Mean widths of the 95 prediction intervals for the average SBP and DBP were 18.2 mmHg and 12.6 mmHg, respectively (Figure 2).

Conclusion

Counting the number of BP ≥135/85 mmHg can provide accurate assessments for the BP levels. R-NHBP/NBP of ≥0.5 is a simple and accurate marker of high BP in HBPM, and R-NHBP/NBP could be a useful tool to assess BP levels in patients practicing HBPM.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

High-frequency electrical properties tomography at 9.4T as a novel contrast mechanism for brain tumors

PURPOSE

To establish high-frequency magnetic resonance electrical properties tomography (MREPT) as a novel contrast mechanism for the assessment of glioblastomas using a rat brain tumor model.

METHODS

Six F98 intracranial tumor bearing rats were imaged longitudinally 8, 11 and 14 days after tumor cell inoculation. Conductivity and mean diffusivity maps were generated using MREPT and Diffusion Tensor Imaging. These maps were co-registered with T2 -weighted images and volumes of interests (VOIs) were segmented from the normal brain, ventricles, edema, viable tumor, tumor rim, and tumor core regions. Longitudinal changes in conductivity and mean diffusivity (MD) values were compared in these regions. A correlation analysis was also performed between conductivity and mean diffusivity values.

RESULTS

The conductivity of ventricles, edematous area and tumor regions (tumor rim, viable tumor, tumor core) was significantly higher (P < .01) compared to the contralateral cortex. The conductivity of the tumor increased over time while MD from the tumor did not change. A marginal positive correlation was noted between conductivity and MD values for tumor rim and viable tumor, whereas this correlation was negative for the tumor core.

CONCLUSION

We demonstrate a novel contrast mechanism based on ionic concentration and mobility, which may aid in providing complementary information to water diffusion in probing the microenvironment of brain tumors.

MRI-Visible Perivascular Spaces in the Centrum Semiovale Are Associated with Brain Amyloid Deposition in Patients with Alzheimer Disease-Related Cognitive Impairment

BACKGROUND AND PURPOSE

The association of perivascular spaces in the centrum semiovale with amyloid accumulation among patients with Alzheimer disease-related cognitive impairment is unknown. We evaluated this association in patients with Alzheimer disease-related cognitive impairment and β-amyloid deposition, assessed with [¹⁸F] florbetaben PET/CT.

MATERIALS AND METHODS

MR imaging and [¹⁸F] florbetaben PET/CT images of 144 patients with Alzheimer disease-related cognitive impairment were retrospectively evaluated. MR imaging-visible perivascular spaces were rated on a 4-point visual scale: a score of ≥3 or <3 indicated a high or low degree of MR imaging-visible perivascular spaces, respectively. Amyloid deposition was evaluated using the brain β-amyloid plaque load scoring system.

RESULTS

Compared with patients negative for β-amyloid, those positive for it were older and more likely to have lower cognitive function, a diagnosis of Alzheimer disease, white matter hyperintensity, the Apolipoprotein E ε4 allele, and a high degree of MR imaging-visible perivascular spaces in the centrum semiovale. Multivariable analysis, adjusted for age and Apolipoprotein E status, revealed that a high degree of MR imaging-visible perivascular spaces in the centrum semiovale was independently associated with β-amyloid positivity (odds ratio, 2.307; 95% CI, 1.036-5.136; P = .041).

CONCLUSIONS

A high degree of MR imaging-visible perivascular spaces in the centrum semiovale independently predicted β-amyloid positivity in patients with Alzheimer disease-related cognitive impairment. Thus, MR imaging-visible perivascular spaces in the centrum semiovale are associated with amyloid pathology of the brain and could be an indirect imaging marker of amyloid burden in patients with Alzheimer disease-related cognitive impairment.

Mask-induced dermatoses during the COVID-19 pandemic: a questionnaire-based study in 12 Korean hospitals

BACKGROUND

During the coronavirus disease 2019 (COVID-19) pandemic, various adverse skin reactions to long-term mask wearing have been reported.

AIM

To assess the clinical features of mask-induced dermatoses and to recommend prevention and treatment options.

METHODS

From April to August 2020, questionnaires including topics such as demographic information, pre-existing skin disorders, reported mask-related symptoms, daily mask-wearing duration and frequency, types of masks used and whether the participant was a healthcare worker, were distributed to patients in 12 hospitals. Dermatologists assessed skin lesions, confirmed diagnosis and recorded treatments.

RESULTS

Itchiness was the most frequent symptom, mostly affecting the cheeks. The most common skin disease was new-onset contact dermatitis (33.94%), followed by new-onset acne (16.97%) and worsening of pre-existing acne (16.97%). Daily wearing of masks was significantly (P = 0.02) associated with new-onset contact dermatitis. More than half of patients with pre-existing skin problems experienced disease worsening while wearing masks. Longer duration of wearing (> 6 h/day, P = 0.04) and use of cotton masks (P < 0.001) significantly increased acne flare-up. Healthcare workers had a higher incidence of skin disease. Skin lesions were generally mild and well tolerated with topical treatment. The study had some limitations: the effect of seasonal characteristics and other risk factors were not assessed, and the patients were visiting dermatological clinics and had interest in their skin status, thus, there may have been selection bias.

CONCLUSION

Mask-induced/-triggered dermatoses contribute to increase the dermatological burden during the pandemic.

An initial experience with a novel technique of single-port robotic resection for rectal cancer

BACKGROUND

The da Vinci single-port (SP) system is designed to facilitate single-incision robotic surgery in a narrow space. We developed a new procedure of rectal resection using this system. The aim of the present study was to evaluate the technical feasibility and safety of SP robotic rectal resection for rectal cancer patients based on our initial experience.

METHODS

A study was conducted on consecutive patients with mid or low rectal cancer who had SP robotic resection at our institution between July and September 2020. The demographic characteristics, perioperative data, and pathology results of the patients were retrospectively analyzed.

RESULTS

There were 5 patients (3 males, 2 females, median age 57 years (range 36-73 years). The median tumor height from the anal verge was 4 cm (range 3-5 cm). Two patients received preoperative chemoradiotherapy for advanced rectal cancer. A single docking was conducted, and the median docking time was 4 min 20 s (range 3 min 30 s to 5 min). The median total operation time was 195 min (range 155-240 min), and the median time of pelvic dissection was 45 min (range 36-62 min). All patients had circumferential and distal tumor-free resection margins. One patient experienced an anastomosis-related complication. The median duration of hospital stay was 7 days (range 7-8 days).

CONCLUSIONS

Our initial experience suggests that SP robotic rectal resection is safe and feasible. Further clinical trials comparing SP and multiport robotic rectal resection should be conducted to verify the superior aspects of this new system.

Familial risk for endometriosis and its interaction with smoking, age at menarche and body mass index: a population-based cohort study among siblings

OBJECTIVE

To quantify familial risk of endometriosis among full siblings and examine interactions between family history and smoking, age at menarche or body mass index (BMI).

DESIGN, SETTING AND POPULATION

Population-based nationwide cohort study.

METHODS

Using data from the Korean National Health Insurance and Screening Programme databases on kinship, healthcare utilisation, lifestyle and anthropometrics, we identified 2 109 288 women with full siblings and their environmental risk factors from 2002 to 2018. Familial risks were estimated using Cox proportional-hazards models, represented as incidence risk ratios (IRR) with 95% CI. Interaction between family history and smoking, age at menarche or BMI were assessed on an additive scale.

MAIN OUTCOME MEASURES

IRR of endometriosis among women with and without affected siblings.

RESULTS

From 19 195 women with affected siblings, 1126 developed endometriosis with an incidence of 35.45/10 000 person-years. Familial risk of endometriosis with versus without affected siblings was increased to IRR 2.75 (95% CI 2.25-3.36), and the highest risk was with affected twins (IRR 6.98; 95% CI 4.19-11.62). Women with both a family history and either smoking, early menarche or low BMI had a significantly higher risk of endometriosis compared with the general population and can be regarded as a high-risk group, the IRRs were 4.28 (95% CI 2.43-7.55), 3.47 (95% CI 2.82-4.26) and 3.09 (95% CI 2.68-3.56), respectively. Substantial effect modification of the associations was noted by smoking and early menarche, as their combined risk with family history exceeded the sum of their individual risks, which was also statistically significant.

CONCLUSION

Genetic factors are the primary contributor to the familial aggregation of endometriosis. Significant gene-environment interaction exists between family history and smoking or early menarche.

High-frequency conductivity at Larmor-frequency in human brain using moving local window multilayer perceptron neural network

Magnetic resonance electrical properties tomography (MREPT) aims to visualize the internal high-frequency conductivity distribution at Larmor frequency using the B1 transceive phase data. From the magnetic field perturbation by the electrical field associated with the radiofrequency (RF) magnetic field, the high-frequency conductivity and permittivity distributions inside the human brain have been reconstructed based on the Maxwell’s equation. Starting from the Maxwell’s equation, the complex permittivity can be described as a second order elliptic partial differential equation. The established reconstruction algorithms have focused on simplifying and/or regularizing the elliptic partial differential equation to reduce the noise artifact. Using the nonlinear relationship between the Maxwell’s equation, measured magnetic field, and conductivity distribution, we design a deep learning model to visualize the high-frequency conductivity in the brain, directly derived from measured magnetic flux density. The designed moving local window multi-layer perceptron (MLW-MLP) neural network by sliding local window consisting of neighboring voxels around each voxel predicts the high-frequency conductivity distribution in each local window. The designed MLW-MLP uses a family of multiple groups, consisting of the gradients and Laplacian of measured B1 phase data, as the input layer in a local window. The output layer of MLW-MLP returns the conductivity values in each local window. By taking a non-local mean filtering approach in the local window, we reconstruct a noise suppressed conductivity image while maintaining spatial resolution. To verify the proposed method, we used B1 phase datasets acquired from eight human subjects (five subjects for training procedure and three subjects for predicting the conductivity in the brain).

Accelerated decomposition of Bi2S3 nanorods in water under an electron beam: a liquid phase transmission electron microscopy study

Evaluating the stability of semiconductor photocatalysts is critical in the development of efficient catalysts. The morphological and microstructural behaviors of nanorod-shaped Bi₂S₃ semiconductors in aqueous solution were studied using a liquid cell transmission electron microscopy (TEM) technique. The rapid decomposition of Bi₂S₃ in water was observed under electron beam irradiation during TEM. Rounded bright spots due to a reduction in thickness were observed on the Bi₂S₃ nanorods at the initial stage of the decomposition, and rounded dark particles appeared outside of the nanorods in the solution, continuing the decomposition. This was confirmed by analyzing the atomic structure of the newly formed small particles, which consisted of an orthorhombic Bi₂S₃ phase. The stability-related decomposition of the Bi₂S₃ nanorods was demonstrated by considering the reduction and oxidation potentials of Bi₂S₃ in an aqueous solution. The effect of water radiolysis by the incident electron during TEM observations on the decomposition process was also determined by considering the time-dependent concentration behavior of the chemical species. Our study therefore reflects a novel route to evaluate the stabilities of semiconductor photocatalysts, which could ultimately solve a range of energy and environmental pollution problems.

Airflow limitation as a risk factor for vascular stiffness

BACKGROUND: Cardiovascular disease is one of the main causes of mortality in patients with chronic obstructive pulmonary disease (COPD), and atherosclerosis is a cause of cardiac comorbidities in COPD. However, it is not clear whether airflow limitation is associated with atherosclerosis irrespective of smoking.OBJECTIVE: To investigate whether airflow limitation is independently associated with vascular stiffness.METHODS: We enrolled 18 893 participants (male 70.5%; mean age 47.5 ± 9.8 years; never smokers 44.2%) who underwent spirometry and brachial-ankle pulse wave velocity (baPWV) as part of a standard health examination at Ajou University Hospital, Suwon, South Korea, from January 2010 to December 2015.We defined vascular peripheral atherosclerosis as baPWV ≥ 1400 cm/s and airflow limitation as pre-bronchodilator ratio of forced expiratory volume in 1 sec (FEV₁) to forced vital capacity (FVC) <70%.RESULTS: Mean baPWV was higher in subjects with airflow limitation (1477.6 ± 331.7 cm/sec, n = 638) than in those without airflow limitation (1344.1 ± 231.8 cm/sec, n = 18255, P < 0.001). In multivariate logistic regression analysis, the following were independent predictors associated with peripheral atherosclerosis (P < 0.05): age, male sex, fasting serum glucose, mean blood pressure, serum leukocyte count, serum low density lipoprotein level and FEV₁.CONCLUSION: Airflow limitation was an independent predictor of vascular stiffness irrespective of smoking history, which suggests that airflow limitation is linked with atherosclerosis.