The empty pelvis syndrome: a core data set from the PelvEx collaborative

BACKGROUND

Empty pelvis syndrome (EPS) is a significant source of morbidity following pelvic exenteration (PE), but is undefined. EPS outcome reporting and descriptors of radicality of PE are inconsistent; therefore, the best approaches for prevention are unknown. To facilitate future research into EPS, the aim of this study is to define a measurable core outcome set, core descriptor set and written definition for EPS. Consensus on strategies to mitigate EPS was also explored.

METHOD

Three-stage consensus methodology was used: longlisting with systematic review, healthcare professional event, patient engagement, and Delphi-piloting; shortlisting with two rounds of modified Delphi; and a confirmatory stage using a modified nominal group technique. This included a selection of measurement instruments, and iterative generation of a written EPS definition.

RESULTS

One hundred and three and 119 participants took part in the modified Delphi and consensus meetings, respectively. This encompassed international patient and healthcare professional representation with multidisciplinary input. Seventy statements were longlisted, seven core outcomes (bowel obstruction, enteroperineal fistula, chronic perineal sinus, infected pelvic collection, bowel obstruction, morbidity from reconstruction, re-intervention, and quality of life), and four core descriptors (magnitude of surgery, radiotherapy-induced damage, methods of reconstruction, and changes in volume of pelvic dead space) reached consensus-where applicable, measurement of these outcomes and descriptors was defined. A written definition for EPS was agreed.

CONCLUSIONS

EPS is an area of unmet research and clinical need. This study provides an agreed definition and core data set for EPS to facilitate further research.

Free-water diffusion magnetic resonance imaging under selegiline treatment in Parkinson's disease

INTRODUCTION

Monoamine oxidase type B inhibitors, including selegiline, are established as anti-Parkinsonian Drugs. Inhibition of monoamine oxidase type B enzymes might suppress the inflammation because of inhibition to generate reactive oxygen species. However, its effect on brain microstructure remains unclear. The aim of this study is to elucidate white matter and substantia nigra (SN) microstructural differences between Patients with Parkinson's disease with and without selegiline treatment by two independently recruited cohorts.

METHODS

Diffusion tensor imaging and free water imaging indices of WM and SN were compared among 22/15 Patients with Parkinson's disease with selegiline (PDselegiline(+)), 33/23 Patients with Parkinson's disease without selegiline (PDselegiline(-)), and 25/20 controls, in the first/second cohorts. Two cohorts were analyzed with different MRI protocols.

RESULTS

Diffusion tensor imaging and free-water indices of major white matter tracts were significantly differed between the PDselegiline(-) and controls in both cohorts, although not between the PDselegiline(+) and controls except for restricted areas. Compared with the PDselegiline(+), free-water was significantly higher in the PDselegiline(-) in the inferior fronto-occipital fasciculus, superior longitudinal fasciculus, and superior and posterior corona radiata (first cohort) and the forceps major and splenium of the corpus callosum (second cohort). There were no significant differences in free-water of anterior or posterior substantia nigra between PDselegiline(+) and PDselegiline(-).

CONCLUSIONS

Selegiline treatment might reduce the white matter microstructural abnormalities detected by free-water imaging in Parkinson's disease.

Factors associated with self-perceived treatment-resistance in bipolar disorder

Patients with bipolar disorder often report self-perceived treatment resistance. However, it is not known to what extent it is due to actual treatment resistance. The Juntendo University provides "Bipolar Disorder Treatment Rebuilding Program," in which patients with self-reported treatment resistant bipolar disorder are hospitalized for 2 weeks and undergo detailed examinations. In this study, we report our experience with the initial 43 patients hospitalized during the one and half years after the launch of the program. Among the patients who underwent full assessment, only one was regarded as having genuine treatment-resistant bipolar disorder without comorbidity. In other cases, ten were not diagnosed with bipolar disorder, 3 had organic brain diseases, 12 had comorbid mental disorders and its symptoms were regarded as treatment-resistant bipolar symptoms by the patients, and 18 did not receive adequate treatment because attendant physicians did not adhere to the treatment guidelines or patients did not adhere to the treatment because of lack of insight. The number of participants was not large, and selection bias hampered the generalization of the findings. Insight and adherence were assessed without the use of validated tools. We could not verify recovery after adequate treatment because of the limited hospitalization period. The findings suggest that most patients with self-perceived treatment-resistant bipolar disorder may not have genuine treatment-resistant bipolar disorder. These results shed light on the difficulties of public education of bipolar disorder and importance of providing appropriate services for diagnosis and treatment of bipolar disorder in the community.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Three-dimensional gait analysis of the effect of directional steering on gait in patients with Parkinson's disease

INTRODUCTION

Deep Brain Stimulation (DBS) is an option to treat advanced Parkinson's Disease (PD), but can cause gait disturbance due to stimulation side efffects. This study aims to evaluate the objective effect of directional current steering by DBS on gait performance in PD, utilizing a three-dimensional gait analysis system.

METHODS

Eleven patients diagnosed with PD and were implanted with directional lead were recruited. The direction of the pyramidal tract (identified by the directional mode screening) was set as 0°. Patients performed the six-meter-walk test and the time up-and-go (TUG) test while an analysis system recorded gait parameters utilizing a three-dimensional motion capture camera. The gait parameters were measured for the baseline, the directional steering at eight angles (0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°), and the conventional ring mode with 1, 2, and 3 mA. Pulse width and frequency were fixed. Placebo stimulation (0 mA) was used for a control.

RESULTS

Eleven patients completed the study. No significant difference were observed between gait parameters during the directional, baseline, placebo, or ring modes during the six-meter-walk test (p > 0.05). During the TUG test, stride length was significantly different between 0° and other directions (p < 0.001), but no significant differences were observed for the other gait parameters. Stride width was non-significantly narrower in the direction of 0°.

CONCLUSION

Controlling stimulation using directional steering may improve gait in patients with PD, while avoiding pyramidal side effects.

Anti-Inflammatory Actions of Expectorants in a Rat Carrageenan-Induced Footpad Edema Model

S-Carboxymethyl-L-cysteine (SCMS) exhibits sputum-regulating and anti-inflammatory actions. Previous studies reported the anti-inflammatory effects of SCMS on chronic inflammatory diseases, but no study has examined these effects on acute inflammatory diseases. In this study, we investigated the anti-inflammatory effects of SCMS in a rat carrageenan-induced footpad edema model, which is routinely used as an acute inflammation model. Expectorants were administered to rats with footpad edema induced by subcutaneously administering 1%λ-carrageenan to the footpad of the left posterior limb, and the dose dependency of the anti-inflammatory effects was evaluated. As a result, even when the dose of SCMS was increased to 400 mg/kg, there were no inhibitory effects on edema. Furthermore, we examined the inhibitory effects of other expectorants (ambroxol hydrochloride, N-acetyl-L-cysteine, L-cysteine ethylester hydrochloride, and L-cysteine methylester hydrochloride), which were reported to exhibit anti-inflammatory effects on chronic inflammation, on edema. However, none of these expectorants inhibited edema.

A potent allele marker related to low bull conception rate in Japanese Black bulls

Over the years, there has been considerable variation in the bull conception rate (BCR) of Japanese Black cattle; moreover, several Japanese Black bulls with a low BCR of ≤10% have been identified. However, the alleles responsible for the low BCR are not determined yet. Therefore, in this study, we aimed to identify single-nucleotide polymorphisms (SNPs) for predicting low BCR. To this end, the genome of Japanese Black bulls was comprehensively examined by a genome-wide association study with whole-exome sequencing (WES), and the effect of the identified marker regions on BCR was determined. The WES analysis of six sub-fertile bulls with a BCR of ≤10% and 73 normal bulls with a BCR of ≥40% identified a homozygous genotype for low BCR in Bos taurus autosome 5 in the region between 116.2 and 117.9 Mb. The g.116408653G > A SNP in this region had the most significant effect on the BCR (P-value = 1.0 × 10^-23), and the GG (55.4 ± 11.2%) and AG (54.4 ± 9.4%) genotypes in the SNP had a higher phenotype than the AA (9.5 ± 6.1%) genotype for the BCR. The mixed model analysis revealed that g.116408653G > A was related to approximately 43% of the total genetic variance. In conclusion, the AA genotype of g.116408653G > A is a useful index for identifying sub-fertile Japanese Black bulls. Some positive and negative effects of SNP on the BCR were presumed to identify the causative mutations, which can help evaluate bull fertility.

Safety and real-world efficacy of lemborexant in the treatment of comorbid insomnia

Aim

To investigate the real-world effectiveness and safety of lemborexan for treating comorbid insomnia associated with other psychiatric disorders, and whether lemborexant helps reduce the dose of benzodiazepines (BZs).

Methods

This retrospective observational study was conducted on outpatients and inpatients treated by physicians of Juntendo University Hospital Mental Clinic between April 2020 and December 2021.

Results

Data of 649 patients who were treated with lemborexant were eventually enrolled. About 64.5% of patients were classified as the responder group. Response rates of ≥60% were recorded for most psychiatric disorders. Upon administration of lemborexant, diazepam-equivalent dose of BZs had been significantly reduced in participants (3.7 ± 8.2 vs. 2.9 ± 7.9, p < 0.001). The results of logistic regression analysis showed that outpatient (odds ratios: 2.310; 95% confidence interval [CI]: 1.32-4.05), shorter duration of BZ use (<1 year) (odds ratios: 1.512; 95% CI: 1.02-2.25), no adverse events (odds ratios: 10.369; 95% CI: 6.13-17.54), larger reduction of diazepam-equivalent dose of BZs upon introducing lemborexant prescription (odds ratios: 1.150; 95% CI: 1.04-1.27), and suvorexant was the replacement drug (odds ratios: 2.983; 95% CI: 1.44-6.19), which were significant predictors of good response.

Conclusion

Although this is a retrospective and observational study with many limitations, our study results suggest that lemborexant is effective and safe.

Deep brain stimulation in posterior subthalamic area for Holmes tremor: Case reports with review of the literature

Background

Holmes tremor (HT) is a refractory tremor associated with cortico-basal ganglia loops and cerebellothalamic tract abnormalities. Various drug treatments have been attempted; however, no treatment method has yet been established. Historically, thalamic deep brain stimulation (DBS) has been performed in medically refractory cases. Recently, the posterior subthalamic area (PSA) has been used for HT. Here, we report cases of HT and review the effectiveness and safety of PSA-DBS for HT.

Cases

We conducted a retrospective chart review of two patients with HT who underwent PSA-DBS. Improvement in tremors was observed 1 year after surgery without apparent complications.

Literature review

We identified 12 patients who underwent PSA-DBS for HT, including our cases. In six patients, PSA was targeted alone; for the rest, the ventralis intermediate nucleus (Vim) of the thalamus and PSA were simultaneously targeted. The Fahn-Tolosa-Marin Tremor Rating Scale improvement rates were 56.8% (range, 33.9-82.1%; n = 6) and 77.8% (range, 42.6-100%; n = 5) for the PSA-DBS and PSA+Vim-DBS, respectively.

Conclusion

Reasonable improvements in HT were observed after PSA-DBS. PSA might be an appropriate target for improving the symptoms of HT. Long-term observations, accumulation of cases, and randomized studies are required in future.

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.

Increasing the class of foundational medication for heart failure is associated with improved prognosis in hospitalized patients with heart failure with reduced or mildly reduced ejection fraction

Aim

To clarify the association between changes in the number of foundational medications for heart failure (FMHF) during hospitalization for worsening heart failure and post-discharge prognosis.

Methods and results

We retrospectively analyzed a combined dataset of three large-scale registries of hospitalized patients with heart failure in Japan (NARA-HF, WET-HF, and REALITY-AHF) and included patients already diagnosed with heart failure with reduced or mildly reduced left ventricular ejection fraction (HFr/mrEF) before admission. Patients were stratified by changes in the number of prescribed FMHF classes, namely angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, beta blockers, and mineralocorticoid receptor blockers, from admission to discharge. The primary endpoint was defined as the combined endpoint of heart failure rehospitalization and all-cause death within 1-year of discharge. The cohort consisted of 1,113 patients, and 482 combined endpoints were observed. In total, 413 (37.1%) patients were on increased FMHF (increased group), 607 (54.5%) remained unchanged (unchanged group), and 93 (8.4%) had a decreased number of FMHF (decreased group) at discharge compared to the time of admission. In multivariable analysis, the increased group was associated with a significantly lower incidence of the primary endpoint compared with the unchanged group (hazard ratio 0.56, 95% confidence interval 0.45–0.60; P&lt;0.001) and decreased group (hazard ratio 0.58, 95% confidence interval 0.40–0.84; P=0.004).

Conclusion

Increasing the number of FMHF cases during heart failure hospitalization is associated with a better prognosis in patients with HFr/mrEF.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): REALITY registry was funded by the Cardiovascular Research Fund of Japan.WET-HF registry was supported by a Grant-in-Aid for Young Scientists (Y.S. JSPS KAKENHI, 18K15860).

Aberrant interaction between TEAD1 and Lamin A/C causes cardiomyopathy

Background

Mutations in the LMNA gene encoding Lamin A/C, a major component of the nuclear lamina, cause laminopathies including dilated cardiomyopathy (DCM). DCM patients with LMNA mutations have particularly severe clinical courses such as heart transplantation and death due to heart failure. However, underlying mechanisms of LMNA-induced DCM remains elusive.

Methods and results

We identified LMNA Q353R mutation in a DCM family with severe heart failure. We generated Q353R heterozygous knock-in mice, which showed sarcomere dysplasia and perinatal lethality. Integrative single-cell analyses of the fetal murine hearts and patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSCMs) revealed that transcriptional regulation of cardiomyocyte maturation/development genes governed by TEAD1 was impaired in LMNA mutant cardiomyocytes. Protein array and immunostaining uncovered increased binding of TEAD1 to mutant Lamin A/C protein and abnormal localization of TEAD1 at the nuclear periphery. Furthermore, TT-10, a Hippo pathway inhibitor, rescued the dysregulation of cardiac developmental genes in LMNA mutant cardiomyocytes. Single-cell RNA-seq of cardiac tissues from DCM patients with the LMNA Q353R mutation confirmed the dysregulated expression of TEAD1 and its target genes. These results demonstrated abnormal interaction between TEAD1 and mutant Lamin A/C impairs structural maturation of cardiomyocytes and suggests that LMNA Q353R-related DCM can be treated through intervention in the Hippo pathway.

Conclusion

TEAD1 trapped by mutant Lamin A/C protein at the nuclear membrane perturbs transcriptional maturation in LMNA Q353R-related DCM.

Funding Acknowledgement

Type of funding sources: None.

O-006 Annotation-free embryo score calculated by iDAScore® correlated with live birth and has no correlation with neonatal outcomes after single vitrified-warmed blastocyst transfer

Study question

Does the embryo score calculated by annotation-free embryo scoring system based on deep learning and time-lapse sequence images correlate with live birth (LB) and neonatal outcomes?

Summary answer

Annotation-free embryo score calculated by iDAScore correlates with decreased miscarriage and increased LB and has no correlation with neonatal outcomes.

What is known already

Embryo ranking models have recently been developed based on artificial intelligence (AI) and deep learning to rank embryos according to their potential for pregnancy. The practicability and usability of such models have been reported. And the previous report suggested iDAScore which is one of the deep learning models for embryo scoring was superior to traditional morphological assessment methods and morphokinetic embryo assessment models. However, few studies have used independent datasets to analyze the correlation between the score calculated by AI models, LB, and neonatal outcomes.

Study design, size, duration

A total of 3,010 single vitrified-warmed blastocyst transfer (SVBT) cycles were analyzed retrospectively. The quality and scoring of embryos were assessed using iDAScore v1.0 (iDAScore, Vitrolife, Sweden). The cohort was divided into four groups based on the iDAScore according to the percentile (9.9-9.3, 9.2-8.7, 8.6-7.3 and, 7.2-1.0).

Participants/materials, setting, methods

Scores were calculated using the iDAScore software module in the Vitrolife Technology Hub (Vitrolife, Gothenburg, Sweden). The correlation between iDAScore, LB rates and total miscarriage (TM), including 1st and 2nd trimester miscarriage, were analysed using a trend-test and multivariable logistic regression analysis. Furthermore, similarly, correlation between the iDAScore and neonatal outcomes were analysed.

Main results and the role of chance

LB rates decreased as the iDAScore decreased (P &lt; 0.05), and a similar inverse trend was observed for the TM rates (P &lt; 0.05). Additionally, multivariate logistic regression analysis showed that iDAScore significantly correlated with increased LB (adjusted odds ratio: 1.742, 95% CI: 1.601–1.904, P &lt; 0.05) and decreased TM (adjusted odds ratio: 0.799, 95% CI: 0.706–0.905, P &lt; 0.05). There was no significant correlation between iDAScore and neonatal outcomes, including congenital malformations, sex, gestational age, and birth weight. Multivariate logistic regression analysis, which included maternal and paternal age, maternal body mass index, parity, smoking, and the presence or absence of caesarean section as confounding factors, revealed no significant difference in any neonatal characteristics (low birth weight, small for gestation, large for gestation, preterm birth, male sex rates, and major congenital malformation).

Limitations, reasons for caution

SVBT was performed following minimal stimulation and natural cycle in vitro fertilisation. Therefore, only a few cycles of elective blastocyst transfer were available. However, there was no bias in selecting embryos for SVBT.

Wider implications of the findings

Objective embryo assessment using a completely automatic and annotation-free model, like iDAScore, showed a good correlation with increased LB and decreased TM. Furthermore, it did not correlate with neonatal outcomes. Therefore, iDAScore may be an optimal LB prediction model after SVBT without affecting neonatal outcomes.

Trial registration number

not applicable

White matter microstructures in Parkinson's disease with and without impulse control behaviors

BACKGROUND

Impulse control behaviors (ICBs) in Parkinson's disease (PD) are thought to be caused by an overdose of dopaminergic therapy in the relatively spared ventral striatum, or by hypersensitivity of this region to dopamine. Alterations in brain networks are now also thought to contribute to the development of ICBs.

OBJECTIVE

To comprehensively assess white matter microstructures in PD patients with ICBs using advanced diffusion MRI and magnetization transfer saturation (MT-sat) imaging.

METHODS

This study included 19 PD patients with ICBs (PD-ICBs), 18 PD patients without ICBs (PD-nICBs), and 20 healthy controls (HCs). Indices of diffusion tensor imaging (DTI), diffusion kurtosis imaging, neurite orientation dispersion and density imaging, and MT-sat imaging were evaluated using tract-based spatial statistics (TBSS), regions of interest (ROIs), and tract-specific analysis (TSA).

RESULTS

Compared with HCs, PD-nICBs had significant alterations in many major white matter tracts in most parameters. In contrast, PD-ICBs had only partial changes in several parameters. Compared with PD-ICBs, TBSS, ROI, and TSA analyses revealed that PD-nICBs had lower axial kurtosis, myelin volume fraction, and orientation dispersion index in the uncinate fasciculus and external capsule, as well as in the retrolenticular part of the internal capsule. These are components of the reward system and the visual and emotional perception areas, respectively.

INTERPRETATION

Myelin and axonal changes in fibers related to the reward system and visual emotional recognition might be more prominent in PD-nICBs than in PD-ICBs.

Analysis of the linear oscillation dynamics of Fluidyne engines

A Fluidyne engine is a liquid piston Stirling engine that uses thermally induced self-sustained oscillations of water and air that are filled in a looped tube and tuning column. It presents high potential for use as a low-temperature-difference Stirling engine with a simple structure. This study analyzes the linear oscillation dynamics of the Fluidyne from a thermoacoustic point of view, with particular emphasis on the local specific acoustic impedance of the working gas, which is given by the ratio of the complex amplitudes of the pressure and velocity oscillations in the regenerator of the Fluidyne. The frequency dependence of the specific acoustic impedance indicates that the gas in the regenerator region undergoes a thermodynamic cycle equivalent to the Stirling cycle when the oscillation frequency is equal to the natural oscillation frequency of the U-shaped liquid column in the Fluidyne. The analysis of the natural oscillation modes determined two key parameters for the desired specific acoustic impedance: the tuning column length and the connecting position to the loop. Experimental verification was achieved via measurements of the onset temperature ratio and acoustic field of a prototype Fluidyne engine.

White matter and nigral alterations in multiple system atrophy-parkinsonian type

Multiple system atrophy (MSA) is classified into two main types: parkinsonian and cerebellar ataxia with oligodendrogliopathy. We examined microstructural alterations in the white matter and the substantia nigra pars compacta (SNc) of patients with MSA of parkinsonian type (MSA-P) using multishell diffusion magnetic resonance imaging (dMRI) and myelin sensitive imaging techniques. Age- and sex-matched patients with MSA-P (n = 21, n = 10 first and second cohorts, respectively), Parkinson’s disease patients (n = 19, 17), and healthy controls (n = 20, 24) were enrolled. Magnetization transfer saturation imaging (MT-sat) and dMRI were obtained using 3-T MRI. Measurements obtained from diffusion tensor imaging (DTI), free-water elimination DTI, neurite orientation dispersion and density imaging (NODDI), and MT-sat were compared between groups. Tract-based spatial statistics analysis revealed differences in diffuse white matter alterations in the free-water fractional volume, myelin volume fraction, and intracellular volume fraction between the patients with MSA-P and healthy controls, whereas free-water and MT-sat differences were limited to the middle cerebellar peduncle in comparison with those with Parkinson’s disease. Region-of-interest analysis of white matter and SNc revealed significant differences in the middle and inferior cerebellar peduncle, pontine crossing tract, corticospinal tract, and SNc between the MSA-P and healthy controls and/or Parkinson’s disease patients. Our results shed light on alterations to brain microstructure in MSA.

Renocardiac protective effects of SGLT2 inhibitor combined with angiotensin receptor blocker in salt sensitive Dahl rats

Background

Kidney plays a central role in regulating salt-sensitivity of blood pressure (BP) to governs sodium excretion via several mechanisms including pressure natriuresis and the actions of renal sodium transporters.

Purpose

We clarified the effects of combination treatment of sodium-glucose cotransporter 2 (SGLT2) inhibitor and angiotensin receptor blocker (ARB) on BP and the pathogenesis of renocardiac injuries, and elucidated underlying molecular mechanisms involved in the regulation of renal sodium handling in the development of salt-sensitivity by comparing with each monotreatment in Dahl salt-sensitive (DSS) hypertensive rats.

Methods

DSS rats were treated orally for 8-weeks with normal salt diet (0.3% NaCl) (NS/Cont group), high salt diet (8% NaCl) (HS/Cont group), high salt diet with ipragliflozin (0.04%) (HS/Ipra group), high salt diet with losartan (0.05%) (HS/Los group), or high salt diet with combination of ipragliflozin and losartan (HS/Ipra+Los group).

Results

The combination group significantly reduced systolic BP compared with either high salt diet control group, losartan or ipragliflozin monotreatment groups (HS/Ipra+Los: 182.5±18.4mmHg vs HS/Cont: 227.7±26.1; HS/Ipra: 216.6±26.9; HS/Los: 208.6±21.6, at 8-weeks of treatment, P&lt;0.05, respectively) (Figure 1A). The slope of pressure-natriuresis curve was significantly increased in the HS/Ipra+Los group compared to that in the HS/Cont group (interaction P=0.024), HS/Ipra group (P=0.009), and HS/Los group (P=0.084) using the linear regression model (Figure 1B), which indicated that only the combination treatment of ipragliflozin and losartan improved salt-sensitivity. The combined treatment significantly improved creatinine clearance (HS/Ipra+Los: 3.3±0.9mL/min vs HS/Cont: 1.1±0.5; HS/Ipra: 1.7±0.6; HS/Los: 1.9±0.8, P&lt;0.05, respectively). The combination treatment also significantly ameliorated glomerulosclerosis, and improved cardiomyocyte hypertrophy and perivascular fibrosis (Figure 1C). Angiotensin II type 1 receptor (AT1R) protein expression level in the kidney was remarkably suppressed in the combination treatment group compared to the other high salt diet groups. The protein expression level of Na+/H+ exchanger isoform 3 (NHE3) and Na+-K+-Cl– cotransporter 2 (NKCC2), two of major sodium transports in the renal tubules, were significantly decreased with losartan monotreatment and combination treatment, but not with ipragliflozin monotreatment (Figure 2).

Conclusions

The dual inhibition of SGLT2 and AT1R effectively improved salt-sensitivity via reducing renal expression levels of the sodium transporters, which eventually lead to renocardiac protection. Thus, the combination treatment could be a novel and useful therapeutic strategy for treating salt-sensitive hypertension and renal injury in non-diabetic patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research

Basidiomycetous Yeast, Glaciozyma antarctica, Forming Frost-Columnar Colonies on Frozen Medium

The basidiomycetous yeast, Glaciozyma antarctica, was isolated from various terrestrial materials collected from the Sôya coast, East Antarctica, and formed frost-columnar colonies on agar plates frozen at −1 °C. Thawed colonies were highly viscous, indicating that the yeast produced a large number of extracellular polysaccharides (EPS). G. antarctica was then cultured on frozen media containing red food coloring to observe the dynamics of solutes in unfrozen water; pigments accumulated in frozen yeast colonies, indicating that solutes were concentrated in unfrozen water of yeast colonies. Moreover, the yeast produced a small quantity of ice-binding proteins (IBPs) which inhibited ice crystal growth. Solutes in unfrozen water were considered to accumulate in the pore of frozen colonies. The extracellular IBPs may have held an unfrozen state of medium water after accumulation in the frost-columnar colony.

O-220 An annotation-free embryo scoring system (iDAScore®) based on deep learning shows high performance for pregnancy prediction after single-vitrified blastocyst transfer

Study question

How is the performance of an automated embryo scoring system for pregnancy prediction after single-vitrified blastocyst transfer (SVBT) compared to other, annotation-dependent blastocyst grading systems?

Summary answer

Automatic embryo ranking by iDAScore shows a higher or equal performance, with regards to pregnancy prediction after SVBT, compared to manual, annotation-dependent grading systems.

What is known already

Blastocyst viability can be assessed by blastocyst morphology grades and/or morphokinetic parameters. However, morphological and morphokinetic embryo assessment is prone to both inter- and intra-observer variation. Recently, embryo ranking models have been developed based on artificial intelligence (AI) and deep learning. Such models rank embryos according to their potential for pregnancy only based on images and do not require any user-dependent annotation. So far, no study has independently assessed the performance of AI models compared to other embryo scoring models, including traditional morphological grading.

Study design, size, duration

A total of 3,014 SVBT cycles were retrospectively analysed. Embryos were stratified according to SART age groups. The quality and scoring of embryos were assessed by iDAScore v1.0 (iDAS, Vitrolife, Sweden), KIDScoreTM D5 v3 (KS; Vitrolife), and Gardner criteria. The performance of the pregnancy prediction for each embryo scoring model was compared using the area under curve (AUC) of the receiver operating characteristic curve for each maternal age group.

Participants/materials, setting, methods

Embryos were cultured in the EmbryoScope+ and EmbryoScopeFlex (Vitrolife). iDAS was automatically calculated using the iDAScore model running on the EmbryoViewer (Vitrolife). KS was calculated in EmbryoViewer after annotation of the required parameters. ICM and TE were annotated according to the Gardner criteria. The degree of expansion in all blastocysts was Grade 4 due to our freezing policy. Furthermore, Gardner’s scores were stratified into four grades (Excellent: AA, Good: AB BA, Fair: BB, Poor: others).

Main results and the role of chance

The AUCs of the &lt; 35 years age group (n = 389) for pregnancy prediction were 0.72 for iDAS, 0.66 for KS and 0.64 for Gardner criteria. The AUC of iDAS was significantly higher (P &lt; 0.05) compared to the other two models. For the 35–37 years age group (n = 514) the AUCs were 0.68, 0.68, and 0.65 for iDAS, KS and Gardner, respectively, and were not significantly different. The AUCs of the 38–40 years age group (n = 796) were 0.67 for iDAS, 0.65 for KS and 0.64 for Gardner criteria and where was not significantly different. The AUCs of the 41–42 years age group (n = 636) were 0.66, 0.66, and 0.63 for iDAS, KS and Gardner, respectively, and there was no significant difference among the pregnancy prediction models. For the &gt; 42 years age group (n = 389) AUCs were 0.76 for iDAS, 0.75 for KS and 0.75 for Gardner criteria and not significantly different. Thus, for all age groups, iDAS was either highest or equal to the highest AUC, although a significant difference was only observed for the youngest age group.

Limitations, reasons for caution

In this study, SVBT was performed after minimal stimulation and natural cycle in vitro fertilisation (IVF). Therefore, we had only few cycles with elective blastocyst transfer. However, there was also no bias in selecting the embryos for SVBT.

Wider implications of the findings

Our results showed that objective embryo assessment by a completely automatic and annotation-free model, iDAScore, does perform as good or even better than more traditional embryo assessment or an annotation-dependent ranking tool. iDAS could be an optimal pregnancy prediction model after SVBT, especially in young and advanced age patients.

Trial registration number

not applicable

Clinical benefits of precision medicine in treating solid cancers: European Society of Medical Oncology-Magnitude of Clinical Benefit Scale score-based analysis

Background

Precision and matched cancer medicine has the potential to complement the existing biomarker approaches in cancer treatment. However, despite their promising potential, certain negative results have highlighted their limitations in molecular biology-driven treatment strategies. This study aimed to evaluate the clinical benefits of precision therapies.

Materials and methods

Three reviewers independently identified and assessed precision and matched cancer treatment studies published between January 2015 and December 2020. Clinical benefits of the treatments included in our cohort were assessed using two established frameworks; the European Society of Medical Oncology-Magnitude of Clinical Benefit Scale version 1.1 (ESMO-MCBS) and the American Society of Clinical Oncology Value Framework.

Results

Of the 290 eligible studies, 130 were for lung cancer, 51 for solid tumors, 24 for melanoma, and 24 for breast cancer. The common targets were: epidermal growth factor receptor (N = 66), serine/threonine-protein kinase B-Raf (N = 40), anaplastic lymphoma kinase (ALK) (N = 34), breast cancer protein (N = 26), phosphatidylinositol-3 kinase/protein kinase B/phosphatase and tensin homolog (PI3K/AKT/PTEN) pathway (N = 19), receptor tyrosine-protein kinase erbB-2 (HER2) (N = 19), mitogen-activated protein kinase (RAS/RAF/MAPK) pathway (N = 18), programmed death-ligand 1 (N = 12), fibroblast growth factor receptor (N = 8), and others (N = 43). The ESMO-MCBS scales ranged from 0 to 4. Based on the clinical benefit values, tumor mutational burden/mismatch repair-deficient/microsatellite instability-high for immunotherapy, anaplastic lymphoma kinase, and neurotrophic receptor tyrosine kinase therapeutic targets were considered high, whereas RAS/RAF/MAPK and PI3K/AKT/PTEN were considered low. Additionally, we found a significant difference between each average score (P < 0.001).

Conclusions

This study showed that precision and matched cancer therapies require further improvement. This is consistent with the views of the tumor board and of clinicians that precision strategies need to be revised to improve their therapeutic effects.

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Of the 290 eligible studies, 130 were for lung cancer, 51 for solid tumors, 24 for melanoma, and 24 for breast cancer.

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Precision strategies need to be revised to improve their therapeutic effects.

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Therapeutic targets need to be narrowed down to improve the efficacy of precision medicine in the clinical setting.

The long-term prognosis of hippocampal neurogenesis and behavioral changes of offspring from rats exposed to valproic acid during pregnancy

Aim

In pregnant women with epilepsy, it is essential to balance maternal safety and the potential teratogenicity of anticonvulsants. Recently, growing evidence has indicated that valproic acid (VPA) can produce postnatal congenital malformations and impair cognitive function. However, the mechanisms underlying cognitive dysfunction in long‐term prognoses remain unclear.

Methods

Pregnant Wistar rats received daily intraperitoneal injections of VPA (200 mg/kg/day) from embryonic day 12.5 until birth. On postnatal day (PD) 149, the rats received an injection of bromodeoxyuridine (BrdU). On PD 150, the rats were subjected to the open field (OF), elevated plus‐maze (EPM), and Y‐maze tests. After behavioral testing, perfusion fixation was performed and the brain was dissected for immunohistochemistry.

Results

A significant marked decrease was seen in the number of BrdU‐positive cells in the dentate gyrus of offspring of VPA‐treated dams compared to those of control. However, no significant differences in hyperactivity were found based on the results of the OF test among the offspring on PD 150 of 200 VPA‐treated dams. In addition, no significant differences were seen in the EPM test.

Conclusion

The behavioral abnormality observed in young offspring of VPA‐treated dams was not significantly different from that of controls in adult offspring on PD 150. However, compared with controls, the number of BrdU‐positive cells in VPA‐treated rats was halved. The findings suggest that the behavioral abnormality seems to improve as they grow, even if some structural abnormalities may remain in the central nervous system.

Pregnant Wistar rats received daily intraperitoneal injections of VPA (200 mg/kg/d) from embryonic day 12.5 until birth. On postnatal day (PD) 149, the rats received an injection of bromodeoxyuridine (BrdU). A significant marked decrease was seen in the number of BrdU‐positive cells in the dentate gyrus of offspring of VPA‐treated dams compared to those of control.

Prognostic impacts of prehospital age shock index in patients with acute myocardial infarction

Introduction

Early identification of high-risk patients is the cornerstone of managing patients with acute myocardial infarction (AMI). Age Shock index (ASI; age multiplied by the ratio of heart rate/systolic blood pressure) has been reported to be similar to Global Registry of Acute Coronary Events (GRACE) risk score for predicting mortality in patients with AMI. However, prognostic impacts of prehospital ASI (pre-ASI) in patients with AMI remain unknown.

Methods

We analyzed of 2578 AMI patients who underwent emergency primary percutaneous coronary intervention (PCI) from January 2013 to March 2018, using data from Mie ACS Registry, a prospective and multicenter registry in Japan. Pre-ASI was recorded by emergency medical services at the first contact with the patient before admission, and in-hospital ASI (in-ASI) was recorded prior to PCI at admission. The primary end point was defined as all-cause death.

Results

Median follow-up duration was 753 days (497–838 days). All-cause death was observed in 230 (8.9%) patients. The ROC-AUC (Receiver operating characteristic-area under the curve) of pre-ASI for all- cause death was 0.76 (p&lt;0.001), which was similar to that of in-ASI (0.78, p&lt;0.001) (p=0.25 for pre-ASI versus in-ASI). The cut-off value for pre-ASI and in-ASI was for the prediction of all-cause death was both 45 with a sensitivity of 0.66 and a specificity of 0.78, with a sensitivity of 0.68 and a specificity of 0.76 respectively. According to the Kaplan-Meier survival analysis by combination of pre-ASI≥45 and in-ASI≥45, the patients with pre-ASI≥45 and in-ASI≥45 showed significantly higher all-cause mortality compared to the patients with pre-ASI≥45 and in-ASI&lt;45, the patients with pre-ASI&lt;45 and in-ASI≥45, and the patients with pre-ASI&lt;45 and in-ASI&lt;45 (p&lt;0.001) (Figure). The addition of pre-ASI≥45 to in-ASI≥45 (global chi-squared score: 205) resulted in a significantly increased global chi-squared score, suggesting the incremental prognostic value of pre-ASI (267; p&lt;0.001). Multivariate cox proportional hazard regression analysis for all-cause mortality demonstrated pre-ASI≥45 was a significant independent predictor (HR: 4.86; 95% CI: 3.36 to 7.02, p&lt;0.001). It was strongest predictor compared to left ventricular ejection fraction&lt;40% (HR: 2.45; 95% CI 1.67 to 3.58, p&lt;0.001), hemodialysis (HR: 3.45; 95% CI 1.66 to 7.17, p=0.001), door to balloon time&gt;90 minutes (HR: 1.66; 95% CI 1.18 to 2.34, p=0.004).

Conclusions

High pre-ASI predict increase mortality and assessment of both high pre-ASI and high in-ASI enhance risk stratification in patients with AMI. Early recognizing high pre-ASI may help us make better strategies and improve prognosis for high-risk AMI patients.

Figure 1

Funding Acknowledgement

Type of funding source: None

Premature acute coronary syndrome patients do not have a better prognosis for their age than mature ACS patients by propensity score match analysis

Background

Acute coronary syndrome (ACS) is the most important cardiovascular (CV) disease with a prevalence that increases with age. There is no data which compared the prognosis with premature ACS and mature ACS using propensity score matched analysis

Purpose

The purpose of this study was to compare the prognosis of premature ACS patients and mature ACS patients using propensity score matched analysis.

Methods

We analyzed of 4249 ACS patients (69.1±12.6, male 77%) including 773 premature ACS patients (50.1±6.8, male 78%) and 3476 mature ACS (73.3±9.3, male 77%) from January 2013 to December 2018, using data from Mie ACS Registry, a prospective and multicenter registry in Japan.

Premature onset of ACS was defined as younger than 65 years old in male and 55 years old in female.

Primary end point was as major adverse cardiac event (MACE) including cardiovascular death, non-fetal myocardial infarction, heart failure requiring admission and unstable angina.

Results

During median follow duration of 742 days ranging from409 to 828 days, 502 MACE were occurred. Premature ACS patients were younger and showed higher body mass index compared to mature ACS patients (50.1±6.8 vs 73.3±9.3 y.o., 25.5 vs 23.0, P&lt;0.001, respectively). However, premature ACS patients were more likely to be associated with ST elevation myocardial infarction, dyslipidemia, family history of coronary artery disease (CAD) and lower Killip classification compared to mature ACS patients (P&lt;0.01, respectively). Common CAD risk factors such as hypertension, diabetes mellitus and past history of CAD were less associated with premature ACS patients compared to mature ACS patients (P&lt;0.01, respectively). Unadjusted Kaplan-Meier survival curves demonstrated the favorable prognosis in premature ACS patients compared to mature ACS patients with hazard ratio of 0.57 (95% CI 0.45–0.71, P&lt;0.001, see Figure 1A). We compared a 1:1 propensity score-matched cohort of 1208 patients with or without premature onset of ACS adjusting the several factors mentioned above (n=604, respectively). Age could not be introduced as a factor of propensity score match when comparing premature and mature ACS patients. After propensity score-match, premature ACS patients is about 18 years younger than mature ACS patients (50.7±6.5 vs 68.5±8.2 y.o., P&lt;0.001). The average age of premature ACS was younger than that of mature ACS, but MACE by Kaplan-Meier survival analysis for premature ACS patients was equivalent to mature ACS patients (P=0.77, see Figure 1B).

Conclusion

Premature ACS patients are required very careful management because they might have factors with unfavorable prognosis, such as lifestyle habit and genetics, that may be beyond age.

Figure 1

Funding Acknowledgement

Type of funding source: None

Right coronary artery as a culprit artery for better prognosis in patients with acute myocardial infarction (AMI) with or without shock

Background

Although patients with acute myocardial infarction (AMI) complicated by cardiogenic shock, morbidity and mortality remain high even with early revascularization and modern intensive care.

Culprit artery and prognosis were associated in patients with acute myocardial infarction.

Purpose

Evaluation of short- and long-term prognosis of AMI with cardiogenic shock by right coronary artery (RCA) and left coronary artery (LCR)

Method

We investigated 3400 AMI patients (age 68.8±12.7 y.o.) were enrolled from Mie ACS registry. They were divided into 4 groups according to the culprit artery and presence or absence of cardiogenic shock: RCA without shock n=1114, RCA with shock n=74, LCA without shock n=2028, LCA with shock n=184. Primary endpoint was defined as all-cause mortality.

Results

During the median follow-up periods with 743 days, 12.6% of the patients experienced all-cause death. RCA and LAC with shock groups demonstrated significantly higher in-hospital mortality compared to groups without shock (p&lt;0.001, Figure 1A). Interestingly, after discharge, LCA with shock group showed significant higher all-cause mortality compared with other 3 groups. Surprisingly, RCA with shock group showed similar favorable prognosis to that of without shock groups (Figure 1B). Multivariate analyses for after discharge mortality showed that LCA with shock group was strongest independent poor prognostic factor with hazard ratio of 2.3 (95% CI 1.4–3.7), but RCA with shock group was not.

Conclusion

Association of cardiogenic shock is the hazardous risk factor for cases with AMI, especially LCA infarction. Surprisingly, RCA AMI cases with shock showed favorable prognosis as well as AMI without shock.

Kaplan-Meier survival curves

Funding Acknowledgement

Type of funding source: None

Prognostic impact of right ventricular overload in patients with acute coronary syndrome

Background

Right ventricular (RV) overload is associated with adverse outcome in patients with chronic heart failure. However, its prognostic value in acute coronary syndrome (ACS) patients remains unknown.

Purpose

The purpose of this study was to investigate the prevalence and prognostic impact of right ventricular overload in ACS patients.

Methods

We studied 2797 ACS patients from Mie ACS registry, a prospective and multicenter registry in Japan. They were divided into 4 subgroups according to the severity of RV overload and the extent of Left Ventricle Ejection Fraction (LVEF) assessed by echocardiography before hospital discharge. High RV overload was defined as trans-tricuspid pressure gradient (TRPG) ≥40mmHg and preserved LVEF was defined as ≥50%. The primary outcome was defined as 2-year all-cause mortality. Median follow up duration was 730 days (1–2215 days).

Results

High RV overload was detected in 76 patients (2.7%). In basic patients characteristics, high RV overload patients were significantly older and higher killip classification than low RV overload patients (P&lt;0.01, respectively). Laboratory data in high RV overload patients showed lower hemoglobin level and higher serum creatinine level than those in low RV overload patients (P&lt;0.01, respectively).

Echocardiographic findings in high RV overload represented lower LVEF, higher rate of moderate or severe mitral regurgitation and left atrial enlargement than those in low RV overload patients (P&lt;0.01, respectively).

During the follow-up periods (median 730 days), 260 (9.3%) patients experienced all-cause death. Multivariate cox hazard regression analysis for all-cause mortality demonstrated that high RV overload was an independent poor prognostic factor in the entire study population. Among patients with preserved LVEF, high RV overload resulted in an increased risk of all-cause mortality compared to low RV overload (P&lt;0.0001).

Conclusion

In ACS patients, high RV overload strongly contributes to worsening of prognosis regardless of the extent of LVEF.

Kaplan-Meier survival curve

Funding Acknowledgement

Type of funding source: None

A novel surgical training simulator for transanal total mesorectal excision

BACKGROUND

The transanal total mesorectal excision (TaTME) approach for rectal cancer has been gaining popularity. Although TaTME requires specific training, the opportunity to obtain this training is limited. We developed the first dry simulator that includes some important structural landmarks to provide training that includes all the procedural steps of TaTME.

METHODS

The model was structured based on a computed tomography scan data. The simulator mimics the rectum and surrounding key anatomical structures. All material components were made of polyvinyl alcohol and stained with various colors to easily identify these anatomical structures while undergoing the training.

RESULTS

Our simulator is compact in its size and can be easily packed, stacked, and stored. The materials mimic the real one and the model allows us to perform the entire step-by-step TaTME procedures with genuine clinical devices from the attachment of operative platform to the anastomosis. We have held the course 24 times to date, with more than 200 surgeons participating not only from domestic hospitals but also from other countries. The result of the satisfaction survey from 65 participants, which was rated from 0 to 10 points, was an average score of 8.6 (± 1.4) points.

CONCLUSIONS

We present the world's first TaTME simulator and believe that it will play an important role for the safe spread of TaTME surgery.