Comparison of short-term outcomes of robotic and laparoscopic transabdominal peritoneal repair for unilateral inguinal hernia: a propensity-score matched analysis

PURPOSE

This study aimed to compare perioperative outcomes of robotic and laparoscopic transabdominal peritoneal repair (TAPP) for unilateral inguinal hernia.

METHODS

This single institutional retrospective cohort study used de-identified data of patients who underwent robotic TAPP (R-TAPP) or laparoscopic TAPP (L-TAPP) for unilateral inguinal hernia between January 1, 2016 and October 31, 2021. Two cohorts were propensity matched, and data were analyzed. The learning curve was evaluated in the R-TAPP group.

RESULTS

Among 938 patients analyzed, 704 were included. After propensity-score matching, 80 patients were included in each group. The difference in operative time between R-TAPP and L-TAPP groups was 10 min (99.5 and 89.5 min, p = 0.087); however, console/laparoscopic time was similar (67 and 66 min, p = 0.71). The dissection time for medial-type hernia in the R-TAPP group was marginally shorter than that in the L-TAPP group (17 and 27 min, p = 0.056); however, there was no difference for lateral-type hernia (38.5 and 40 min p = 0.37). Perioperative variables, including estimated blood loss, postoperative hospital stay, and postoperative pain, had no significant difference, and chronic pain, which needed medication or intervention, was not observed in each group. The number of cases needed to achieve plateau performance was 7-10 in the R-TAPP group.

CONCLUSION

This study suggests that R-TAPP was safely introduced, and its perioperative outcomes were not inferior to those of L-TAPP. A shorter dissection time for medial-type hernia might be due to the robot's advantages, and a fast-learning curve could help with the early standardization of the procedure.

Impact of transcatheter aortic valve implantation on coronary flow reserve by transthoracic Doppler echocardiography 1-year after the intervention in severe aortic stenosis patients

Background

Coronary flow reserve (CFR) which is one of indexes reflecting coronary microcirculation in patients without significant epicardial coronary lesions can be impaired in patients with severe aortic stenosis (AS). It has been shown that CFR is an independent predictor for future cardiovascular events in AS patients. Transcatheter aortic valve implantation (TAVI) has rapidly become widespread and is becoming the standard treatment for severe AS. This procedure may have a good effect on CFR due to reduction of severe afterload in patients with severe AS. Although the recent reports evaluated change in CFR immediately and 6 months after TAVI, it has not been evaluated whether impaired CFR improves 1-year after TAVI in AS patients with preserved left ventricular ejection fraction (LVEF).

Purpose

The purpose of the present study was to investigate whether impaired CFR improves 1-year after TAVI in severe AS patients with preserved LVEF.

Methods

The study population consists of consecutive 105 patients with severe AS undergoing TAVI. Exclusion criteria were atrial fibrillation, old myocardial infarction, history of coronary artery bypass grafting, significant lesions in the left anterior descending artery (LAD), moderate or severe mitral valve disease, history of valve replacement, LVEF <50% and preoperative CFR >2.2. CFR was obtained from coronary flow velocity by transthoracic echocardiography at rest and maximal hyperemia in LAD before, immediately and 1-year after TAVI. We compared CFR between before and after TAVI in the study patients who did not meet the exclusion criteria.

Results

After exclusion of 76 patients who met the exclusion criteria, the final study patients consist of 29 patients (8 male, 84.9±5.2 years). There was no significant difference in LVEF (61.3±3.4% vs 61.6±4.4%, P=0.667) and LV end-diastolic volume (LVEDVI; 58.2±9.2 mL/m2 vs 55.8±9.0 mL/m2, P=0.089) between before and immediately after TAVI. LVEF (61.0±2.8%, P=0.721) and LVEDVI (58.0±9.1 mL/m2, P=0.949) 1-year after TAVI were similar to those before TAVI. There was no significant difference in coronary flow velocity at rest between before and immediately after TAVI (27.4±8.9 vs 24.4±7.0 cm/s, P=0.051) and between before and 1-year after TAVI (25.9±8.3 cm/s, P=0.396). Coronary flow velocity at maximal hyperemia 1-year after TAVI significantly increased compared with that before TAVI (from 48.8±13.9 to 67.9±21.0 cm/s, P<0.001) while there was no significant difference between before and immediately after TAVI (52.0±12.0 cm/s, P=0.186). Impaired CFR before TAVI (1.82±0.28) increased immediately (2.03±0.39, P=0.009) and 1-year after TAVI (2.69±0.57, P<0.001).

Conclusions

The present results suggest that impaired CFR in patients with preserved LVEF improves 1-year after TAVI. TAVI may have a good effect on CFR in severe AS patients with preserved LVEF.

Funding Acknowledgement

Type of funding sources: None.

3D Quantitative Synthetic MRI in the Evaluation of Multiple Sclerosis Lesions

BACKGROUND AND PURPOSE

Synthetic MR imaging creates multiple contrast-weighted images based on a single time-efficient quantitative scan, which has been mostly performed for 2D acquisition. We assessed the utility of 3D synthetic MR imaging in patients with MS by comparing its diagnostic image quality and lesion volumetry with conventional MR imaging.

MATERIALS AND METHODS

Twenty-four patients with MS prospectively underwent 3D quantitative synthetic MR imaging and conventional T1-weighted, T2-weighted, FLAIR, and double inversion recovery imaging, with acquisition times of 9 minutes 3 seconds and 18 minutes 27 seconds for the synthetic MR imaging and conventional MR imaging sequences, respectively. Synthetic phase-sensitive inversion recovery images and those corresponding to conventional MR imaging contrasts were created for synthetic MR imaging. Two neuroradiologists independently assessed the image quality on a 5-point Likert scale. The numbers of cortical lesions and lesion volumes were quantified using both synthetic and conventional image sets.

RESULTS

The overall diagnostic image quality of synthetic T1WI and double inversion recovery images was noninferior to that of conventional images (P = .23 and .20, respectively), whereas that of synthetic T2WI and FLAIR was inferior to that of conventional images (both Ps < .001). There were no significant differences in the number of cortical lesions (P = .17 and .53 for each rater) or segmented lesion volumes (P = .61) between the synthetic and conventional image sets.

CONCLUSIONS

Three-dimensional synthetic MR imaging could serve as an alternative to conventional MR imaging in evaluating MS with a reduced scan time.

Changes of QT interval in the acute phase after pulmonary vein isolation for paroxysmal atrial fibrillation

Introduction

Pulmonary vein isolation (PVI) affects ganglionated plexi (GP) around the atrium, leading to a modification of the intrinsic cardiac autonomic system (ANS). In animal models, GP ablation has a potential risk of QT prolongation and ventricular arrhythmias. However, the impact of PVI on QT intervals in humans remains unclear.

Purpose

This study aims to evaluate the Impact of PVI on QT interval in patients with paroxysmal atrial fibrillation.

Methods

We analyzed consecutive 117 PAF patients for their first PVI procedures. 12-lead ECG was evaluated at baseline, 4 hr, day 1, 1 month, and 3 months after ablation. Only patients with sinus rhythm on 12-lead ECG at each evaluation point without antiarrhythmic drugs were included.

Results

Heart rate significantly increased at 4 hr, day 1, and 1 month. Raw QT interval prolonged at 4 hr (417.1±41.6 ms, P&lt;0.001) but shortened at day 1 (376.4±34.1 ms, P&lt;0.001), 1 month (382.2±31.5 ms, P&lt;0.001), and 3 months (385.1±32.8 ms, P&lt;0.001) compared to baseline (391.6±31.4 ms). Bazett- and Fridericia- corrected QTc intervals significantly prolonged at 4hr (Bazett: 430.8±27.9 ms, P&lt;0.001; Fridericia: 425.8±27.4 ms, P&lt;0.001), day1 (Bazett: 434.8±22.3 ms, P&lt;0.001; Fridericia: 414.1±23.7 ms, P&lt;0.001), 1M (Bazett: 434.8±22.3 ms, P&lt;0.001; Fridericia: 408.2±21.0 ms, P&lt;0.05), and 3M (Bazett: 420.1±21.8 ms, P&lt;0.001; Fridericia: 407.8±21.1 ms, P&lt;0.05) compared to baseline (Bazett: 404.9±25.2 ms; Fridericia: 400.0±22.6 ms). On the other hand, Framingham- and Hodges- corrected QTc interval significantly prolonged only at 4hr (Framingham: 424.1±26.6 ms, P&lt;0.001; Hodges: 426.8±28.4 ms, P&lt;0.001) and at day1 (Framingham: 412.3±29.3 ms, P&lt;0.01; Hodges: 410.6±40.2 ms, P&lt;0.05) compared to baseline (Framingham: 399.2±22.7 ms; Hodges: 400.7±22.8 ms). At 4 hr after ablation, raw QT and QTc of all formulas significantly prolonged than baseline. Raw QT and QTc prolongation at 4hr after ablation were more frequently observed in female patients. Multiple regression analysis revealed that female patient is a significant predictor of raw QT and QTc interval prolongation of all formulas 4hr after PVI.

Conclusions

Raw QT and QTc prolonged after PVI, especially in the acute phase. Female patient is a risk factor for QT prolongation in the acute phase after PVI.

Funding Acknowledgement

Type of funding source: None

AB1137 CLASSIFICATION OF THE EARLY STAGE OF RAPIDLY DESTRUCTIVE COXOPATHY ACCORDING TO THE FEMORAL HEAD DESTRUCTION

Background:

Rapidly destructive coxopathy (RDC) is an unusual subset of osteoarthritis of the hip characterized by rapid chondrolysis with progressive loss of the joint space as the first manifestation of the disease. Because rapid progression of RDC makes it difficult to obtain sequential radiographs in its early stage, the process of disease progression in the early stage remains unclear. Although the pathogenesis of RDC is still unclarified, the potential causes of RDC include subchondral insufficiency fracture of the femoral head resulting from osteoporosis, pelvic posterior inclination in RDC as a mechanical factor, and increased serum levels of matrix metalloproteinase (MMP)-3 as a biological factor.

Objectives:

This study aimed to differentiate the process of disease progression in the early stage of RDC and provide its new classification system.

Methods:

This monocentric retrospective study included 42 female patients who met the criteria of RPOH, chondrolysis >2 mm during 12 months from the onset of hip pain based on a series of radiographs and computed tomography (CT). This study also included 9 female patients with osteoarthritis secondary to developmental dysplasia of the hip (DDH), who demonstrated chondrolysis >2 mm during 12 months from the onset of hip pain. Cortical thickness index (CTI) correlated with bone mineral density of the hip, pelvic tilt, and serum concentrations of matrix metalloproteinase (MMP)-3 were analyzed.

Results:

RDC were classified into two types based on the absence (type 1, n=17) and presence (type 2, n=25) of subsequent femoral head destruction shown by CT within 12 months after the onset of hip pain. MMP-3 significantly increased in RDC type 2 compared with type 1 and DDH. Increased posterior pelvic tilt was found in RDC type 2 compared with DDH. Logistic regression and receiver operating characteristic curve analyses indicated that MMP-3 may be associated with differentiation between RDC types 1 and 2. No difference was found in CTI between RDC types and DDH.

RDC type 2 hips developed partial (type 2A) and massive (type 2B) femoral head destruction within the first 12 months. Whereas partial destruction showed <20% collapse ratio, massive destruction demonstrated >40% collapse ratio. Increased posterior pelvic tilt was found in massive destruction. Femoral head destruction started earlier within the first 6 months in massive destruction compared with that in partial destruction. From receiver operating characteristic curve analysis, pelvic tilt differentiated the femoral head destruction types using the initial radiograph at the onset before first demonstration of femoral head destruction. No difference was found in CTI or MMP-3 between the two subtypes.

Conclusion:

Disease progression of RDC during 12 months after the onset of hip pain could be classified into two distinct types based on the absence (type 1) and presence (type 2) of femoral head destruction in association with MMP-3 and pelvic tilt as biological and mechanical factors, respectively. MMP-3 may be helpful to differentiate those two types in the early stage of RPOH. The extent of femoral head destruction could further differentiate RDC type 2 into two subtypes based on pelvic tilt.

Acknowledgments :

This study was supported by the Japan Hip Joint Foundation.

Disclosure of Interests:

None declared

Long-term follow-up of the randomized trial of mesorectal excision with or without lateral lymph node dissection in rectal cancer (JCOG0212)

BACKGROUND

Japan Clinical Oncology Group (JCOG) 0212 (ClinicalTrials.gov NCT00190541) was a non-inferiority phase III trial of patients with clinical stage II-III rectal cancer without lateral pelvic lymph node enlargement. The trial compared mesorectal excision (ME) with ME and lateral lymph node dissection (LLND), with a primary endpoint of recurrence-free survival (RFS). The planned primary analysis at 5 years failed to confirm the non-inferiority of ME alone compared with ME and LLND. The present study aimed to compare ME alone and ME with LLND using long-term follow-up data from JCOG0212.

METHODS

Patients with clinical stage II-III rectal cancer below the peritoneal reflection and no lateral pelvic lymph node enlargement were included in this study. After surgeons confirmed R0 resection by ME, patients were randomized to receive ME alone or ME with LLND. The primary endpoint was RFS.

RESULTS

A total of 701 patients from 33 institutions were assigned to ME with LLND (351) or ME alone (350) between June 2003 and August 2010. The 7-year RFS rate was 71.1 per cent for ME with LLND and 70·7 per cent for ME alone (hazard ratio (HR) 1·09, 95 per cent c.i. 0·84 to 1·42; non-inferiority P = 0·064). Subgroup analysis showed improved RFS among patients with clinical stage III disease who underwent ME with LLND compared with ME alone (HR 1·49, 1·02 to 2·17).

CONCLUSION

Long-term follow-up data did not support the non-inferiority of ME alone compared with ME and LLND. ME with LLND is recommended for patients with clinical stage III disease, whereas LLND could be omitted in those with clinical stage II tumours.

A two-way molecular dialogue between embryo and endosperm is required for seed development

The plant embryonic cuticle is a hydrophobic barrier deposited de novo by the embryo during seed development. At germination, it protects the seedling from water loss and is, thus, critical for survival. Embryonic cuticle formation is controlled by a signaling pathway involving the ABNORMAL LEAF SHAPE1 subtilase and the two GASSHO receptor-like kinases. We show that a sulfated peptide, TWISTED SEED1 (TWS1), acts as a GASSHO ligand. Cuticle surveillance depends on the action of the subtilase, which, unlike the TWS1 precursor and the GASSHO receptors, is not produced in the embryo but in the neighboring endosperm. Subtilase-mediated processing of the embryo-derived TWS1 precursor releases the active peptide, triggering GASSHO-dependent cuticle reinforcement in the embryo. Thus, a bidirectional molecular dialogue between embryo and endosperm safeguards cuticle integrity before germination.

P1518 Relationship between post-operative asymptomatic status and reverse remodeling of large left atrium in patients with aortic stenosis who underwent aortic valve replacement

Introduction

Recently, we have reported that large left atrial volume (minimum left atrial volume index : LAVImin ≥30ml/m²) at end-diastole determined by direct exposure of left ventricular (LV) end-diastolic pressure can predict post-operative symptomatic status after aortic valve replacement (AVR) in aortic stenosis (AS) patients with high sensitivity and modest specificity. Reverse remodeling of large LAVImin after AVR may contribute to false positive for the prediction of post-operative symptomatic status in patients with AS.

Purpose

The purpose of this study was to evaluate relationship between post-operative symptomatic status and reverse remodeling of large LAVImin in patients with AS who underwent AVR.

Methods

The study population consisted of 75 patients with AS who underwent AVR and were followed up for 600 days after AVR, after the exclusion of the followings; atrial fibrillation, significant coronary artery disease, significant mitral valve disease, pacemaker rhythm, and inadequate echocardiographic images. We measured LAVImin by biplane Simpson"s method before and after AVR. Preoperative large LAVImin (≥30ml/m²) according to the previous study was observed in 32 (43%) of 75 patients. We divided these 32 patients into two groups according to the post-operative symptomatic status during the follow-up period.

Results

There was no significant difference in pre-operative LAVImin between patients with and without post-operative symptom (46.5 ± 13.4 vs 40.4 ± 8.6 ml/m²). On the other hand, post-operative LAVImin in patients without post-operative symptom was significantly smaller than that in patients with post-operative symptom (31.5 ± 8.6 vs 54.8 ± 14.0 ml/m², p &lt; 0.01). While significant regression in LAVImin after AVR was observed in patients without post-operative symptom (40.4 ± 8.6 to 31.5 ± 8.6 ml/m², p &lt; 0.05), no regression in LAVImin after AVR was observed in patients with post-operative symptom (46.5 ± 13.4 to 54.8 ± 14.0 ml/m²).

Conclusions

Reverse remodeling of large LAVmin in patients with AS who underwent AVR was observed in post-operative asymptomatic group, but not in symptomatic group. These results suggest that reverse remodeling of large LAVImin after AVR could contribute to the post-operative asymptomatic status in patients with AS who underwent AVR.

P2850Time to isolation guided hot balloon ablation for pulmonary vein isolation

Background

One disadvantage of hot balloon ablation (HBA) system is that real time monitoring of pulmonary vein (PV) potential is technically impossible. Therefore, the optimal radiofrequency-generated thermal energy application duration and application number are not completely established.

Purpose

The aim of this study is to evaluate the utility of 2Fr 4-electrode unidirectional catheter inserted into PV along with HB for real time monitoring of PV potential and investigate the time to isolation (TTI) guided optimal application strategy for HB based PV isolation in the acute phase.

Methods

We evaluated 23 consecutive patients who performed PV isolation using HBA system. Real time monitoring of PV potential was performed by 2Fr 4-electrode unidirectional catheter inserted into PV along with HB (Figure1A). After HBA applications, PV isolation was validated by high-resolution mapping with the 20-pole steerable mapping (PENTARAY) catheter as a standard. PV potentials during HBA application were categorized into five patterns. PV potentials disappeared during HBA applications and not emerged again (acute isolation), disappeared but verified by PENTARAY catheter (pseudo isolation), once disappeared but emerged again during the same application (acute reconnection), visible but not disappeared (ineffective application) and Invisible (Figure1B).

TTI, difference between TTI and time to reach target temperature (TTRT), balloon temperature at isolation and ablation time after isolation were examined for each applications.

Results

Out of 92 PVs, 69/92 (75.0%) PVs were isolated using HBA and 23/92 (25.0%) PVs required touch up ablation. In total, 120 applications were performed. Real time monitoring of the PV activity was obtained in 114 of 120 applications (95.0%). The distribution of PV potential patterns were 64/120 (53.3%), 2/120 (1.7%), 27/120 (22.5%), 23/120 (19.2%), for acute isolation, pseudo isolation, acute reconnection, ineffective application, respectively.

TTI and difference between TTI and TTRT were significantly shorter in the acute isolation group. Balloon temperature at isolation was significantly lower, TTRT and ablation time after isolation was significantly longer in the acute isolation group. Among them, TTI and difference between TTI and TTRT were highly predictive by receiver operation characteristics curve analysis. TTI <36.5s predicted successful application with sensitivity 83.9% and specificity 79.3%. Difference between TTI and TTRT <6.5s predicted with sensitivity 82.3% and specificity 89.7%.

Figure 1

Conclusions

In HBA system, real time monitoring of PV potentials can be obtained using 2Fr 4-electrode unidirectional catheter and accuracy to confirm an ostial PV isolation is relatively high.

TTI <36.5s and difference between TTI and TTRT <6.5s could be a suitable target for effective application.

P5636Lipid core burden index is associated with microcirculatory dysfunction even in stable angina pectoris; Insights from intracoronary electrocardiography

Background

Combined near-infrared spectroscopy (NIRS) and intravascular ultrasonography (NIRS-IVSU) is an imaging modality for precise detection of lipid core burden. Distal embolization has been reported to be a mechanism of microcirculatory dysfunction (MD) caused by percutaneous coronary intervention (PCI). High lipid core burden index at the 4-mm maximal segment (max-LCBI(4)) has been associated with the cardiovascular event. A max-LCBI(4) of >500 was related to perioperative myocardial infarction even in patients with stable angina pectoris. Unlike 12-lead electrocardiography, intracoronary electrocardiography can detect slight ischemia during PCI, maybe indicating distal embolization. However, whether PCI for culprit plaques with a low max-LCBI(4) can cause MD is unclear. Thus, this study aimed to investigate whether plaques with low max-LCBI(4) influence MD, using intracoronary electrocardiography.

Methods

Forty consecutive patients who underwent PCI for stable angina pectoris due to stenosis of the proximal segment of the left anterior descending artery were enrolled. NIRS-IVUS was performed in all the patients before predilatation to evaluate for the culprit lesion. Total LCBI and max-LCBI(4) within the culprit lesion were measured. On gray-scale IVUS, vessel area, lumen area, plaque volume, and percent (%) plaque volume were measured. Intracoronary electrography was performed at stent implantation to measure the time from the initiation of S-T segment elevation from the isoelectric baseline to the return of S-T segment to the isoelectric baseline after the deflation of the stent balloon, which was defined as the severity of the MD. The patients were divided into 2 groups according to median max-LCBI(4) (high [n=20] and low LCBI groups [n=20]).

Results

The mean age was 72±6 years. Of the patients, 80% were male. The mean overall max-LCBI(4) was 140±100. Max-LCBI(4) was significantly higher in the high-LCBI(4) group than in the low-LCBI(4) group. No significant differences in age, body mass index, American College of Cardiology and American Heart Association classification, and low-density lipoprotein level were found between the groups, as well as in the gray-scale IVUS parameters such as %plaque volume. The mean time from the initiation of the initiation of S-T segment elevation from the isoelectric baseline to the return of S-T segment to the isoelectric baseline was significantly longer in the high LCBI group than in the low LCBI group (33 vs 12 sec, P=0.01) despite no change in the S-T segment on 12-lead electrography. The S-T segment elevation occurred only during stent balloon inflation and returned to the isoelectric baseline immediately after stent balloon deflation at a max-LCBI(4) of 0. The no-reflow and slow flow phenomena were not observed.

Conclusion

Even low max-LCBI(4) on NIRS-IVUS was associated with MD during PCI in patients with stable angina pectoris.

P6257Low systolic blood pressure on admission as a predictor of outcome in octogenarian patients with heart failure and preserved ejection fraction

Background

Heart failure (HF) is an epidemic in healthcare worldwide including Asia. It appears that HF will become more serious with aging of the population. The patients with heart failure and preserved ejection fraction (HFpEF) were older, more often female, and frequently have comorbidities including hypertension. However, lower systolic blood pressure (SBP) on admission is associated with poor outcomes in patients with HF. It remains unclear whether this association is similar in very elderly patients with HFpEF.

Purpose

To investigate clinical features and prognosis in octogenarian HFpEF subjects.

Methods

We analyzed 87 consecutive subjects aged 80 years or older who were hospitalized for acute decompensated HF with left ventricular ejection fraction (LVEF) ≥50% between 2015 and 2017. Clinical characteristics and a composite event of cardiac death and HF hospitalization were compared in two groups according to SBP cut-off of 140 mmHg on admission.

Results

The prevalence of lower SBP subjects (mean BP = 118 mmHg) and higher SBP (mean BP = 166 mmHg) subjects were 41.4% and 58.6%, respectively. Lower SBP subjects were more comorbid with atrial fibrillation (72.2 vs. 45.1%, p=0.01). In the lower SBP group, diuretics, mineralocorticoid receptor antagonists (MRA), beta-blockers and ACE inhibitors/ARBs were more commonly used than higher SBP group (Table). During the observational period (median = 1.0 year), lower SBP on admission was associated with a 2.65-fold [95% confidence interval (CI): 1.29–5.55, p=0.009] greater likelihood of experiencing the composite events of cardiac death and rehospitalization for HF (Figure). This observation was still consistent even after adjusting clinical demographics and comorbidity [hazard ratio = 2.95, 95% CI: 1.30–6.87, p=0.01].

Table 1 Lower SBP group (n=36) Higher SBP group (n=51) P-value Atrial fibrillation (%) 72.2 0.01 0.01 Loop diuretic (%) 97.1 83.7 0.08 MRA (%) 47.1 24.5 0.04 Beta-blocker (%) 52.9 44.9 0.51 ACE inhibitor/ARB (%) 59.2 29.4 0.01

Figure 1

Conclusions

In octogenarian patients with acute decompensated HF and preserved LVEF, SBP on admission less than 140 mmHg is significantly associated with poor outcomes. Future studies need to prospectively evaluate optimal SBP treatment goals in very elderly patients with HFpEF.

White Matter Abnormalities in Multiple Sclerosis Evaluated by Quantitative Synthetic MRI, Diffusion Tensor Imaging, and Neurite Orientation Dispersion and Density Imaging

BACKGROUND AND PURPOSE

A number of MR-derived quantitative metrics have been suggested to assess the pathophysiology of MS, but the reports about combined analyses of these metrics are scarce. Our aim was to assess the spatial distribution of parameters for white matter myelin and axon integrity in patients with relapsing-remitting MS by multiparametric MR imaging.

MATERIALS AND METHODS

Twenty-four patients with relapsing-remitting MS and 24 age- and sex-matched controls were prospectively scanned by quantitative synthetic and 2-shell diffusion MR imaging. Synthetic MR imaging data were used to retrieve relaxometry parameters (R1 and R2 relaxation rates and proton density) and myelin volume fraction. Diffusion tensor metrics (fractional anisotropy and mean, axial, and radial diffusivity) and neurite orientation and dispersion index metrics (intracellular volume fraction, isotropic volume fraction, and orientation dispersion index) were retrieved from diffusion MR imaging data. These data were analyzed using Tract-Based Spatial Statistics.

RESULTS

Patients with MS showed significantly lower fractional anisotropy and myelin volume fraction and higher isotropic volume fraction in widespread white matter areas. Areas with different isotropic volume fractions were included within areas with lower fractional anisotropy. Myelin volume fraction showed no significant difference in some areas with significantly decreased fractional anisotropy in MS, including in the genu of the corpus callosum and bilateral anterior corona radiata, whereas myelin volume fraction was significantly decreased in some areas where fractional anisotropy showed no significant difference, including the bilateral posterior limb of the internal capsule, external capsule, sagittal striatum, fornix, and uncinate fasciculus.

CONCLUSIONS

We found differences in spatial distribution of abnormality in fractional anisotropy, isotropic volume fraction, and myelin volume fraction distribution in MS, which might be useful for characterizing white matter in patients with MS.

Improving the Quality of Synthetic FLAIR Images with Deep Learning Using a Conditional Generative Adversarial Network for Pixel-by-Pixel Image Translation

BACKGROUND AND PURPOSE

Synthetic FLAIR images are of lower quality than conventional FLAIR images. Here, we aimed to improve the synthetic FLAIR image quality using deep learning with pixel-by-pixel translation through conditional generative adversarial network training.

MATERIALS AND METHODS

Forty patients with MS were prospectively included and scanned (3T) to acquire synthetic MR imaging and conventional FLAIR images. Synthetic FLAIR images were created with the SyMRI software. Acquired data were divided into 30 training and 10 test datasets. A conditional generative adversarial network was trained to generate improved FLAIR images from raw synthetic MR imaging data using conventional FLAIR images as targets. The peak signal-to-noise ratio, normalized root mean square error, and the Dice index of MS lesion maps were calculated for synthetic and deep learning FLAIR images against conventional FLAIR images, respectively. Lesion conspicuity and the existence of artifacts were visually assessed.

RESULTS

The peak signal-to-noise ratio and normalized root mean square error were significantly higher and lower, respectively, in generated-versus-synthetic FLAIR images in aggregate intracranial tissues and all tissue segments (all P < .001). The Dice index of lesion maps and visual lesion conspicuity were comparable between generated and synthetic FLAIR images (P = 1 and .59, respectively). Generated FLAIR images showed fewer granular artifacts (P = .003) and swelling artifacts (in all cases) than synthetic FLAIR images.

CONCLUSIONS

Using deep learning, we improved the synthetic FLAIR image quality by generating FLAIR images that have contrast closer to that of conventional FLAIR images and fewer granular and swelling artifacts, while preserving the lesion contrast.

Medication-related osteonecrosis of the jaw after tooth extraction in cancer patients: a multicenter retrospective study

Root amputation, immunosuppressive therapy, mandibular tooth extraction, pre-existing inflammation, and longer duration of treatment with bone-modifying agents were significantly associated with an increased risk of medication-related osteonecrosis of the jaw. Hopeless teeth should be extracted without drug holiday before the development of inflammation in cancer patients receiving high-dose bone-modifying agents.

INTRODUCTION

No studies have comprehensively analyzed the influence of pre-existing inflammation, surgical procedure-related factors such as primary wound closure, demographic factors, and drug holiday on the incidence of medication-related osteonecrosis of the jaw (MRONJ). The purpose of this study was to retrospectively investigate the relationships between these various factors and the development of MRONJ after tooth extraction in cancer patients receiving high-dose bone-modifying agents (BMAs) such as bisphosphonates or denosumab.

METHODS

Risk factors for MRONJ after tooth extraction were evaluated with univariate and multivariate analyses. The following parameters were investigated in all patients: demographics, type and duration of BMA use, whether BMA use was discontinued before tooth extraction (drug holiday), the duration of such discontinuation, the presence of pre-existing inflammation, and whether additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed.

RESULTS

We found that root amputation (OR = 22.62), immunosuppressive therapy (OR = 16.61), extraction of mandibular teeth (OR = 12.14), extraction of teeth with pre-existing inflammation, and longer duration (≥ 8 months) of high-dose BMA (OR = 7.85) were all significantly associated with MRONJ.

CONCLUSIONS

Tooth extraction should not necessarily be postponed in cancer patients receiving high-dose BMA. The effectiveness of a short-term drug holiday was not confirmed, as drug holidays had no significant impact on MRONJ incidence. Tooth extraction may be acceptable during high-dose BMA therapy until 8 months after initiation.

Automatic DPC Code Selection from Electronic Medical Records

Objectives: We extracted index terms related to diseases recorded in hospital discharge summaries and examined the capability of the vector space model to select a suitable diagnosis with these terms.

Methods: By morphological analysis, we extracted index terms and constructed an original dictionary for the discharge summary analysis. We chose 125 different DPC (Japanese DRG system) codes for the diseases, each of which had more than 20 cases. We divided them into two groups. One group consisted of 5927 cases from 2004 fiscal year and was used to generate the document vector space according to the DPC. The other group of 3187 cases was collected to verify the automatic DPC selection by using data from 2005 fiscal year. The top 200 extracted index terms for each disease were used to calculate the weight of each disease.

Results: The DPC code obtained by the calculated similarity was compared with the original codes of patients for 125 DPCs of 3187 cases. Eighty percent of the cases matched the diagnosis of the DPC (first six digits) and 56% of the cases completely matched all 14 digits of the DPC.

Conclusions: We demonstrated that we could extract suitable terms for each disease and obtain characteristics, such as the diagnosis, from the calculated vectors. This technique can be used to measure the qualification of discharge summaries and to integrate discharge summaries among different facilities. By the text mining technique, we can characterize the contents of electronic discharge summaries and deduce diagnoses with the data.

Effects of Aerobic and Resistance Training Combined with Fortified Milk on Muscle Mass, Muscle Strength, and Physical Performance in Older Adults: A Randomized Controlled Trial

OBJECTIVES

Fortified milk and resistance training (RT) increase muscle mass, muscle strength, and physical performance in older adults, but it remains unclear whether RT combined with aerobic training (AT) would have stronger effects on these outcomes. The purpose of this study was to examine the effects of aerobic and resistance training (ART) combined with fortified milk consumption on muscle mass, muscle strength, and physical performance in older adults.

DESIGN

Open-labeled randomized controlled trial.

SETTING

University of Tsukuba.

PARTICIPANTS

Fifty-six older adults aged 65-79.

INTERVENTION

Participants were randomly allocated into resistance training (RT + fortified milk, n = 28) and aerobic and resistance training (ART + fortified milk, n = 28) groups. All participants attended supervised exercise programs twice a week at University of Tsukuba and ingested fortified milk every day for 12 weeks. Skeletal muscle index ([SMI]: appendicular lean mass/height2) was assessed using dual-energy X-ray absorptiometry as a muscle mass measure. One-repetition maximum strength was measured using four kinds of resistance training machines (chest press, leg extension, leg curl, and leg press) as muscle strength measures. Sit-to-stand and arm curl tests were also assessed as physical performance measures.

MEASUREMENTS

The primary measurements were muscle mass and strength. The secondary outcomes were physical performance, blood samples, habitual diet, habitual physical activity, and medication use.

RESULTS

Although the muscle strength and physical performance measures significantly improved in both groups, SMI significantly improved in only the RT group. There was no significant difference in the change in SMI and muscle strength measures between the two groups. However, the change in sit-to-stand and arm curl measures in the ART group were significantly higher than those in the RT group.

CONCLUSIONS

These results suggest that AT before RT combined with fortified milk consumption has similar effects on skeletal muscle mass and strength compared with RT alone, but it may be a more useful strategy to improve physical performance in older adults. Although the mechanism of our intervention is uncertain, our program would be an effective prevention for sarcopenia in older adults.

Myeloperoxidase in blood neutrophils during normal and abnormal menstrual cycles in women of reproductive age

INTRODUCTION

We previously reported that granulocyte colony-stimulating factor (G-CSF) plays a critical role in ovulation, suggesting that neutrophils may maintain ovulation. We assessed myeloperoxidase (MPO), a major and specific enzyme of neutrophils, in women with abnormal and normal menstrual cycles to clarify the relationship between MPO and ovulation.

METHODS

We analyzed MPO activity in blood neutrophils of women with abnormal menstrual cycles (indicative of anovulation, n = 12) and age- and body mass index-matched normal menstrual cycles (indicative of ovulation, n = 24) using two parameters as a marker of MPO, Neut X and mean peroxidase index (MPXI).

RESULTS

MPO of women with abnormal menstrual cycles was significantly lower than that of women with normal menstrual cycles [Neut X: 62.6 ± 1.1 (mean ± standard error of the mean) vs. 66.2 ± 0.3, P = 0.009; MPXI: -0.54 ± 1.66 vs. 4.91 ± 0.53, P = 0.008]. Among women with normal menstrual cycles, MPO was highest in the follicular phase (Neut X: 67.0 ± 0.3; P = 0.033).

CONCLUSION

The difference in MPO between women with abnormal and normal menstrual cycles and the upregulation of MPO before ovulation suggest that neutrophils and MPO are closely related to ovulation.

Ultrasonographic Abdominal Screening of Atomic Bomb-Exposed Subjects

Abdominal ultrasonographic screening for cancer was performed in 6001 Hiroshima and Nagasaki A-bomb exposed and comparison subjects, all members of the Adult Health Study of the Radiation Effects Research Foundation, formerly the Atomic Bomb Casualty Commission. This study yielded 20 cancers, including 7 hepatocellular, 3 gastric, 3 renal and 2 urinary bladder cancers; one cancer each of the ovary, pancreas, colon and ureter; and one cancer metastatic to the liver, whose primary was unknown. Seventeen of these 20 subjects manifested no symptoms or signs of their disease. A variety of additional tumors, unproven and probably benign, including uterine myomata, and other abnormalities were also detected. Abdominal ultrasonographic screening greatly assisted in the detection of cancers, most of which neither the patients nor their physicians were aware. In this screened fixed population sample the cancer detection rate was 0.33%, exceeding any such rates previously reported in the medical literature.

Male sexual dysfunction after rectal cancer surgery: Results of a randomized trial comparing mesorectal excision with and without lateral lymph node dissection for patients with lower rectal cancer: Japan Clinical Oncology Group Study JCOG0212

BACKGROUND

We conducted a randomized controlled trial (JCOG0212) to determine whether the outcome of mesorectal excision (ME) alone for rectal cancer is not inferior to that of ME with lateral lymph node dissection (LLND). The present study focused on male sexual dysfunction after surgery.

METHODOLOGY

Eligibility criteria included clinical stage II/III rectal cancer, the lower margin of the lesion below the peritoneal reflection, the absence of lateral pelvic lymph node enlargement, and no preoperative radiotherapy. After confirmation of R0 resection by ME, patients were intraoperatively randomized. Questionnaires using the International Index of Erectile Function (IIEF-5) about the sexual function of men were collected before and 1 year after surgery. Sexual dysfunction incidence was defined as the ratio of patients showing sexual dysfunction after surgery relative to the number who had no erectile dysfunction before surgery.

RESULTS

Among 701 patients enrolled between June 2003 and August 2010, 472 males were included. Among them, 343 (73%) completed preoperative and postoperative questionnaires. According to the study protocol, the incidences of sexual dysfunction in patients who underwent ME alone and ME with LLND were 68% (17/25; 95%CI, 47-85%) and 79% (23/29; 95%CI, 60-92%), respectively (p = 0.37). Incidences of sexual dysfunction in patients with no or only mild erectile dysfunction before surgery who underwent ME alone and ME with LLND were 59% (48/81) and 71% (67/95), respectively (p = 0.15). Multivariate analysis identified age as the only risk factor for sexual dysfunction after surgery (p = 0.02).

CONCLUSIONS

LLND may not increase sexual dysfunction incidence after rectal cancer surgery. This incidence is associated with increased age. This trial is registered with ClinicalTrials.gov, number NCT00190541 and University Hospital Medical Information Network Clinical Trials Registry, number C000000034.

New Determination Method of Flowability and Demolding Properties in Polyurethane Rigid Molded Foams

This paper describes a method of determinating the flowability and demolding property of molded polyurethane rigid foams by the dynamic viscoelasticity spectrometer. In response to periodic stimulations, the dynamic viscoelasticity gives us much physical information of polymers, including flowability and demolding properties. The flowability and demolding property can be determined from viscoelasticities and blowing pressures during the foaming process, which are measured with the newly developed apparatus. With this newly developed apparatus we show measurement examples on many kinds of systems, such as variation of base polyols (different functionalities) and blowing agent (CFC-11, HCFC-141b and cyclopentane), etc..

Embolisation of Ruptured Cerebral Aneurysms with Interlocking Detachable Coils in Acute Stage

Twelve cases of ruptured cerebral aneurysm were treated in acute stage with interlocking detachable coils (IDC, Target Therapeutics, Fremont, California) and the outcome was assessed.

IDCs were placed intra-aneurysm for intra-aneurysmal occlusion, or intra-artery for proximal occlusion. Cases: age 36–84 (mean; 60) y.o., 11 females and 1male; 1, 5, 4 and 2 patients were categorised (Hunt and Hess) as grades 1, 2, 3 and 4 respectively. An intra-aneurysmal occlusion in ten cases and a proximal occlusion in two were performed on day 1–11 (mean 4).

On angiograms and CT findings, the ruptured point seemed to have occluded in all cases. The occlusion rate was 100% in five cases, 95% in two, 90% in three, 80% in one, and less than 50% in one.

There were two cases of technical complication, one a coil migration and the other an aneurysmal perforation with IDC.

Their Glasgow Outcome Scale six months after embolisation was graded as good recovery in four cases, moderately disabled state in two, severely disabled state in one, and dead in five. Follow-up angiograms taken four to six months after embolisation showed an intra-aneurysmal coil compaction in five cases. Two of these were treated by a second embolisation or by neck clipping followed by aneurysmal resection, but another two were observed without any treatment and the last one died of rebleeding. Histological examination of the resected embolised aneurysm revealed slight organization around coils but no endothelialisation over the aneurysmal orifice.

In our experience, coil embolisation with IDC for acute ruptured aneurysm is a promising means of preventing rerupture during subacute stage.

Ischemic Preconditioning Enhances Muscle Endurance during Sustained Isometric Exercise

Ischemic preconditioning (IPC) enhances whole-body exercise endurance. However, it is poorly understood whether the beneficial effects originate from systemic (e. g., cardiovascular system) or peripheral (e. g., skeletal muscle) adaptations. The present study examined the effects of IPC on local muscle endurance during fatiguing isometric exercise. 12 male subjects performed sustained isometric unilateral knee-extension exercise at 20% of maximal voluntary contraction until failure. Prior to the exercise, subjects completed IPC or control (CON) treatments. During exercise trial, electromyography activity and near-infrared spectroscopy-derived deoxygenation in skeletal muscle were continuously recorded. Endurance time to task failure was significantly longer in IPC than in CON (mean±SE; 233±9 vs. 198±9 s, P<0.001). Quadriceps electromyography activity was not significantly different between IPC and CON. In contrast, deoxygenation dynamics in the quadriceps vastus lateralis muscle was significantly faster in IPC than in CON (27.1±3.4 vs. 35.0±3.6 s, P<0.01). The present study found that IPC can enhance muscular endurance during fatiguing isometric exercise. Moreover, IPC accelerated muscle deoxygenation dynamics during the exercise. Therefore, we suggest that the origin of beneficial effects of IPC on exercise performance may be the enhanced mitochondrial metabolism in skeletal muscle.

Effect of high energy electrons on H⁻ production and destruction in a high current DC negative ion source for cyclotron

Recently, a filament driven multi-cusp negative ion source has been developed for proton cyclotrons in medical applications. In this study, numerical modeling of the filament arc-discharge source plasma has been done with kinetic modeling of electrons in the ion source plasmas by the multi-cusp arc-discharge code and zero dimensional rate equations for hydrogen molecules and negative ions. In this paper, main focus is placed on the effects of the arc-discharge power on the electron energy distribution function and the resultant H(-) production. The modelling results reasonably explains the dependence of the H(-) extraction current on the arc-discharge power in the experiments.