Exploring the impact of super-resolution deep learning on MR angiography image quality.

PURPOSE: The aim of this study is to assess the effect of super-resolution deep learning-based reconstruction (SR-DLR), which uses k-space properties, on image quality of intracranial time-of-flight (TOF) magnetic resonance angiography (MRA) at 3 T. METHODS: This retrospective study involved 35 patients who underwent intracranial TOF-MRA using a 3-T MRI system with SR-DLR based on k-space properties in October and November 2022. We reconstructed MRA with SR-DLR (matrix = 1008 × 1008) and MRA without SR-DLR (matrix = 336 × 336). We measured the signal-to-noise ratio (SNR), contrast, and contrast-to-noise ratio (CNR) in the basilar artery (BA) and the anterior cerebral artery (ACA) and the sharpness of the posterior cerebral artery (PCA) using the slope of the signal intensity profile curve at the half-peak points. Two radiologists evaluated image noise, artifacts, contrast, sharpness, and overall image quality of the two image types using a 4-point scale. We compared quantitative and qualitative scores between images with and without SR-DLR using the Wilcoxon signed-rank test. RESULTS: The SNRs, contrasts, and CNRs were all significantly higher in images with SR-DLR than those without SR-DLR (p < 0.001). The slope was significantly greater in images with SR-DLR than those without SR-DLR (p < 0.001). The qualitative scores in MRAs with SR-DLR were all significantly higher than MRAs without SR-DLR (p < 0.001). CONCLUSION: SR-DLR with k-space properties can offer the benefits of increased spatial resolution without the associated drawbacks of longer scan times and reduced SNR and CNR in intracranial MRA.

Effect of deep learning-based reconstruction on high-resolution three-dimensional T2-weighted fast asymmetric spin-echo imaging in the preoperative evaluation of cerebellopontine angle tumors.

PURPOSE: We aimed to evaluate the effect of deep learning-based reconstruction (DLR) on high-spatial-resolution three-dimensional T2-weighted fast asymmetric spin-echo (HR-3D T2-FASE) imaging in the preoperative evaluation of cerebellopontine angle (CPA) tumors. METHODS: This study included 13 consecutive patients who underwent preoperative HR-3D T2-FASE imaging using a 3 T MRI scanner. The reconstruction voxel size of HR-3D T2-FASE imaging was 0.23 × 0.23 × 0.5 mm. The contrast-to-noise ratios (CNRs) of the structures were compared between HR-3D T2-FASE images with and without DLR. The observers' preferences based on four categories on the tumor side on HR-3D T2-FASE images were evaluated. The facial nerve in relation to the tumor on HR-3D T2-FASE images was assessed with reference to intraoperative findings. RESULTS: The mean CNR between the tumor and trigeminal nerve and between the cerebrospinal fluid and trigeminal nerve was significantly higher for DLR images than non-DLR-based images (14.3 ± 8.9 vs. 12.0 ± 7.6, and 66.4 ± 12.0 vs. 53.9 ± 8.5, P < 0.001, respectively). The observer's preference for the depiction and delineation of the tumor, cranial nerves, vessels, and location relation on DLR HR-3D T2FASE images was superior to that on non-DLR HR-3D T2FASE images in 7 (54%), 6 (46%), 6 (46%), and 6 (46%) of 13 cases, respectively. The facial nerves around the tumor on HR-3D T2-FASE images were visualized accurately in five (38%) cases with DLR and in four (31%) without DLR. CONCLUSION: DLR HR-3D T2-FASE imaging is useful for the preoperative assessment of CPA tumors.

Optimizing High-Resolution MR Angiography: The Synergistic Effects of 3D Wheel Sampling and Deep Learning-Based Reconstruction.

OBJECTIVE: The aim of this study was to assess the utility of the combined use of 3D wheel sampling and deep learning-based reconstruction (DLR) for intracranial high-resolution (HR)-time-of-flight (TOF)-magnetic resonance angiography (MRA) at 3 T. METHODS: This prospective study enrolled 20 patients who underwent head MRI at 3 T, including TOF-MRA. We used 3D wheel sampling called "fast 3D" and DLR for HR-TOF-MRA (spatial resolution, 0.39 × 0.59 × 0.5 mm3) in addition to conventional MRA (spatial resolution, 0.39 × 0.89 × 1 mm3). We compared contrast and contrast-to-noise ratio between the blood vessels (basilar artery and anterior cerebral artery) and brain parenchyma, full width at half maximum in the P3 segment of the posterior cerebral artery among 3 protocols. Two board-certified radiologists evaluated noise, contrast, sharpness, artifact, and overall image quality of 3 protocols. RESULTS: The contrast and contrast-to-noise ratio of fast 3D-HR-MRA with DLR are comparable or higher than those of conventional MRA and fast 3D-HR-MRA without DLR. The full width at half maximum was significantly lower in fast 3D-MRA with and without DLR than in conventional MRA (P = 0.006, P < 0.001). In qualitative evaluation, fast 3D-MRA with DLR had significantly higher sharpness and overall image quality than conventional MRA and fast 3D-MRA without DLR (sharpness: P = 0.021, P = 0.001; overall image quality: P = 0.029, P < 0.001). CONCLUSIONS: The combination of 3D wheel sampling and DLR can improve visualization of arteries in intracranial TOF-MRA.

Motion robust coronary MR angiography using zigzag centric ky-kz trajectory and high-resolution deep learning reconstruction.

PURPOSE: To develop a new MR coronary angiography (MRCA) technique by employing a zigzag fan-shaped centric ky-kz k-space trajectory combined with high-resolution deep learning reconstruction (HR-DLR). METHODS: All imaging data were acquired from 12 healthy subjects and 2 patients using two clinical 3-T MR imagers, with institutional review board approval. Ten healthy subjects underwent both standard 3D fast gradient echo (sFGE) and centric ky-kz k-space trajectory FGE (cFGE) acquisitions to compare the scan time and image quality. Quantitative measures were also performed for signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) as well as sharpness of the vessel. Furthermore, the feasibility of the proposed cFGE sequence was assessed in two patients. For assessing the feasibility of the centric ky-kz trajectory, the navigator-echo window of a 30-mm threshold was applied in cFGE, whereas sFGE was applied using a standard 5-mm threshold. Image quality of MRCA using cFGE with HR-DLR and sFGE without HR-DLR was scored in a 5-point scale (non-diagnostic = 1, fair = 2, moderate = 3, good = 4, and excellent = 5). Image evaluation of cFGE, applying HR-DLR, was compared with sFGE without HR-DLR. Friedman test, Wilcoxon signed-rank test, or paired t tests were performed for the comparison of related variables. RESULTS: The actual MRCA scan time of cFGE with a 30-mm threshold was acquired in less than 5 min, achieving nearly 100% efficiency, showcasing its expeditious and robustness. In contrast, sFGE was acquired with a 5-mm threshold and had an average scan time of approximately 15 min. Overall image quality for MRCA was scored 3.3 for sFGE and 2.7 for cFGE without HR-DLR but increased to 3.6 for cFGE with HR-DLR and (p < 0.05). The clinical result of patients obtained within 5 min showed good quality images in both patients, even with a stent, without artifacts. Quantitative measures of SNR, CNR, and sharpness of vessel presented higher in cFGE with HR-DLR. CONCLUSION: Our findings demonstrate a robust, time-efficient solution for high-quality MRCA, enhancing patient comfort and increasing clinical throughput.

Intracranial aneurysms treated with stent-assisted coil embolization: evaluation with four-dimensional ultrashort-TE MR angiography.

OBJECTIVES: As a novel follow-up method for intracranial aneurysms treated with stent-assisted coil embolization (SACE), we developed four-dimensional magnetic resonance angiography (MRA) with minimized acoustic noise utilizing ultrashort-echo time (4D mUTE-MRA). We aimed to assess whether 4D mUTE-MRA is useful for the evaluation of intracranial aneurysms treated with SACE. METHODS: This study included 31 consecutive patients with intracranial aneurysm treated with SACE who underwent 4D mUTE-MRA at 3 T and digital subtraction angiography (DSA). For 4D mUTE-MRA, five dynamic MRA images with a spatial resolution of 0.5 × 0.5 × 0.5 mm3 were obtained every 200 ms. Two readers independently reviewed the 4D mUTE-MRA images to evaluate the aneurysm occlusion status (total occlusion, residual neck, and residual aneurysm) and the flow in the stent using a 4-point scale (from 1 [not visible] to 4 [excellent]). The interobserver and intermodality agreement was assessed using κ statistics. RESULTS: On DSA images, 10 aneurysms were classified as total occlusion, 14 as residual neck, and 7 as residual aneurysm. In terms of aneurysm occlusion status, the intermodality and interobserver agreement was excellent (κ = 0.92 and κ = 0.96, respectively). For the flow in the stents on 4D mUTE-MRA, the mean score was significantly higher for single stents than multiple stents (p < .001) and for open-cell type stents than closed-cell type (p < .01). CONCLUSIONS: 4D mUTE-MRA is a useful tool with a high spatial and temporal resolution for the evaluation of intracranial aneurysms treated with SACE. KEY POINTS: • In the evaluation of intracranial aneurysms treated with SACE on 4D mUTE-MRA and DSA, the intermodality and interobserver agreement in aneurysm occlusion status was excellent. • 4D mUTE-MRA shows good to excellent visualization of flow in the stents, especially for cases treated with a single or open-cell stent. • 4D mUTE-MRA can provide hemodynamic information related to embolized aneurysms and the distal arteries to stented parent arteries.

Feasibility study of super-resolution deep learning-based reconstruction using k-space data in brain diffusion-weighted images.

PURPOSE: The purpose of this study is to evaluate the influence of super-resolution deep learning-based reconstruction (SR-DLR), which utilizes k-space data, on the quality of images and the quantitation of the apparent diffusion coefficient (ADC) for diffusion-weighted images (DWI) in brain magnetic resonance imaging (MRI). METHODS: A retrospective analysis was performed on 34 patients who had undergone DWI using a 3 T MRI system with SR-DLR reconstruction based on k-space data in August 2022. DWI was reconstructed with SR-DLR (Matrix = 684 × 684) and without SR-DLR (Matrix = 228 × 228). Measurements were made of the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) in white matter (WM) and grey matter (GM), and the full width at half maximum (FWHM) of the septum pellucidum. Two radiologists assessed image noise, contrast, artifacts, blur, and the overall quality of three image types using a four-point scale. Quantitative and qualitative scores between images with and without SR-DLR were compared using the Wilcoxon signed-rank test. RESULTS: Images with SR-DLR showed significantly higher SNRs and CNRs than those without SR-DLR (p < 0.001). No statistically significant variances were found in the apparent diffusion coefficients (ADCs) in WM and GM between images with and without SR-DLR (ADC in WM, p = 0.945; ADC in GM, p = 0.235). Moreover, the FWHM without SR-DLR was notably lower compared to that with SR-DLR (p < 0.001). CONCLUSION: SR-DLR has the potential to augment the quality of DWI in DL MRI scans without significantly impacting ADC quantitation.

A preliminary study of deep learning-based reconstruction specialized for denoising in high-frequency domain: usefulness in high-resolution three-dimensional magnetic resonance cisternography of the cerebellopontine angle.

PURPOSE: Deep learning-based reconstruction (DLR) has been developed to reduce image noise and increase the signal-to-noise ratio (SNR). We aimed to evaluate the efficacy of DLR for high spatial resolution (HR)-MR cisternography. METHODS: This retrospective study included 35 patients who underwent HR-MR cisternography. The images were reconstructed with or without DLR. The SNRs of the CSF and pons, contrast of the CSF and pons, and sharpness of the normal-side trigeminal nerve using full width at half maximum (FWHM) were compared between the two image types. Noise quality, sharpness, artifacts, and overall image quality of these two types of images were qualitatively scored. RESULTS: The SNRs of the CSF and pons were significantly higher with DLR than without DLR (CSF 21.81 ± 7.60 vs. 15.33 ± 4.03, p < 0.001; pons 5.96 ± 1.38 vs. 3.99 ± 0.48, p < 0.001). There were no significant differences in the contrast of the CSF and pons (p = 0.225) and sharpness of the normal-side trigeminal nerve using FWHM (p = 0.185) without and with DLR, respectively. Noise quality and the overall image quality were significantly higher with DLR than without DLR (noise quality 3.95 ± 0.19 vs. 2.53 ± 0.44, p < 0.001; overall image quality 3.97 ± 0.17 vs. 2.97 ± 0.12, p < 0.001). There were no significant differences in sharpness (p = 0.371) and artifacts (p = 1) without and with DLR. CONCLUSION: DLR can improve the image quality of HR-MR cisternography by reducing image noise without sacrificing contrast or sharpness.

Psychiatric symptoms influence reward-seeking and loss-avoidance decision-making through common and distinct computational processes.

AIM: Psychiatric symptoms are often accompanied by impairments in decision-making to attain rewards and avoid losses. However, due to the complex nature of mental disorders (e.g., high comorbidity), symptoms that are specifically associated with deficits in decision-making remain unidentified. Furthermore, the influence of psychiatric symptoms on computations underpinning reward-seeking and loss-avoidance decision-making remains elusive. Here, we aim to address these issues by leveraging a large-scale online experiment and computational modeling. METHODS: In the online experiment, we recruited 1900 non-diagnostic participants from the general population. They performed either a reward-seeking or loss-avoidance decision-making task, and subsequently completed questionnaires about psychiatric symptoms. RESULTS: We found that one trans-diagnostic dimension of psychiatric symptoms related to compulsive behavior and intrusive thought (CIT) was negatively correlated with overall decision-making performance in both the reward-seeking and loss-avoidance tasks. A deeper analysis further revealed that, in both tasks, the CIT psychiatric dimension was associated with lower preference for the options that recently led to better outcomes (i.e. reward or no-loss). On the other hand, in the reward-seeking task only, the CIT dimension was associated with lower preference for recently unchosen options. CONCLUSION: These findings suggest that psychiatric symptoms influence the two types of decision-making, reward-seeking and loss-avoidance, through both common and distinct computational processes.

Effects of Deep Learning Reconstruction Technique in High-Resolution Non-contrast Magnetic Resonance Coronary Angiography at a 3-Tesla Machine.

PURPOSE: To evaluate the effects of deep learning reconstruction (DLR) in qualitative and quantitative image quality of non-contrast magnetic resonance coronary angiography (MRCA). METHODS: Ten healthy volunteers underwent conventional MRCA (C-MRCA) and high-resolution (HR) MRCA on a 3T magnetic resonance imaging with a voxel size of 1.8 × 1.1 × 1.7 mm3 and 1.8 × 0.6 × 1.0 mm3, respectively, for C-MRCA and HR-MRCA. High-resolution magnetic resonance coronary angiography was also reconstructed with the DLR technique (DLR-HR-MRCA). We compared the contrast-to-noise ratio (CNR) and visual evaluation scores for vessel sharpness and traceability of proximal and distal coronary vessels on a 4-point scale among 3 image series. RESULTS: The vascular CNR value on the C-MRCA and the DLR-HR-MRCA was significantly higher than that on the HR-MRCA in the proximal and distal coronary arteries (13.9 ± 6.4, 11.3 ± 4.4, and 7.8 ± 2.6 for C-MRCA, DLR-HR-MRCA, and HR-MRCA, P < .05, respectively). Mean visual evaluation scores for the vessel sharpness and traceability of proximal and distal coronary vessels were significantly higher on the HR-DLR-MRCA than the C-MRCA (P < .05, respectively). CONCLUSION: Deep learning reconstruction significantly improved the CNR of coronary arteries on HR-MRCA, resulting in both higher visual image quality and better vessel traceability compared with C-MRCA.

Association between oral candidiasis and bacterial pneumonia: A retrospective study.

OBJECTIVE: To investigate associated risk factors for oral candidiasis in elderly patients hospitalized in a community-based acute-care hospital with no dental units. METHODS: Two hundred and twenty-eight elderly patients (male: 105, female: 123), who were hospitalized with several systemic diseases in a community-based acute-care hospital from May 2014 to October 2016, were retrospectively analysed by multiple logistic regression. RESULTS: Multiple logistic regression analysis shows that bacterial pneumonia has a statistically strong relationship with oral candidiasis (p = 0.000, OR: 5.173, 95% CI: 2.368-11.298). The order followed is poor oral hygiene (p = 0.001, OR: 6.095, 95% CI: 2.003-18.545) and severe dry mouth (p = 0.043, OR: 2.507, 95% CI: 1.031-6.098). Other correlated factors including diabetes mellitus, denture wearer, dysphagia, malnutrition, requiring care and use of inhalation steroids, were not statistically significant in this study. CONCLUSIONS: Bacterial pneumonia correlates with oral candidiasis.

Introducing laparoscopic total gastrectomy for gastric cancer in general practice: a retrospective cohort study based on a nationwide registry database in Japan.

BACKGROUND: Although laparoscopic total gastrectomy (LTG) is considered a technically demanding procedure with safety issues, it has been performed in several hospitals in Japan. Data from a nationwide web-based data entry system for surgical procedures (NCD) that started enrollment in 2011 are now available for analysis. METHODS: A retrospective cohort study was conducted using data from 32,144 patients who underwent total gastrectomy and were registered in the NCD database between January 2012 and December 2013. Mortality and morbidities were compared between patients who received LTG and those who underwent open total gastrectomy (OTG) in the propensity score-matched Stage I cohort and Stage II-IV cohort. RESULTS: There was no significant difference in mortality rate between LTG and OTG in both cohorts. Operating time was significantly longer in LTG while the blood loss was smaller. In the Stage I cohort, LTG, performed in 33.6% of the patients, was associated with significantly shorter hospital stay but significantly higher incidence of readmission, reoperation, and anastomotic leakage (5.4% vs. 3.6%, p < 0.01). In the Stage II-IV cohort, LTG was performed in only 8.8% of the patients and was associated with significantly higher incidence of leakage (5.7% vs. 3.6%, p < 0.02) although the hospital stay was shorter (15 days vs. 17 days, p < 0.001). CONCLUSION: LTG was more discreetly introduced than distal gastrectomy, but remained a technically demanding procedure as of 2013. This procedure should be performed only among the well-trained and informed laparoscopic team.

Surgical risk and benefits of laparoscopic surgery for elderly patients with gastric cancer: a multicenter prospective cohort study.

BACKGROUND: Laparoscopic gastrectomy (LG) might have greater clinical benefits for elderly patients as less invasive surgery; however, there is still little evidence to support its benefit. We evaluated the surgical outcomes of elderly patients in a nationwide prospective cohort study. METHODS: One hundred and sixty-nine participating institutions were identified by stratified random sampling, and were adjusted for hospital volume, type and location. During 1 year from 2014 to 2015, consecutive patients who underwent gastrectomy for gastric cancer were prospectively enrolled. 'Elderly' was defined as ≥ 75 years of age, based on the prevalence of comorbidities and the activities of daily living of patients of this age. We compared the surgical outcomes of LG to those of open gastrectomy (OG) in non-elderly and elderly patients. The primary outcome was the incidence of severe morbidities (Grade ≥ 3). RESULTS: Eight thousand nine hundred and twenty-seven patients were enrolled [non-elderly, n = 6090 (OG, n = 2602; LG, n = 3488); elderly, n = 2837 (OG, n = 1471; LG, n = 1366)]. Grade ≥ 3 complications occurred in 161 (10.9%) patients who underwent OG and 98 (7.2%) who underwent LG (p < 0.001). After adjusting for confounding factors, we confirmed that laparoscopic surgery was not an independent risk factor (odds ratio = 0.81, 0.60-1.09). OG was associated with a significantly longer median length of postoperative stay in comparison to LG (16 versus 12 days, p < 0.001). There were no significant differences in the incidence of other postoperative comorbidities. CONCLUSION: The safety of LG in elderly patients was demonstrated. LG shortened the length of postoperative hospital stay.

Predicting anxiety state using smartphone-based passive sensing.

This study predicts the change of stress levels using real-world and online behavioral features extracted from smartphone log information. Previous studies of stress detection using smartphone data focused on a single feature and did not consider all features simultaneously. We propose a method to extract a co-occurring combination of a user's real-world and online behavioral features by converting raw sensor data into categorical features. We conducted an experiment in which the State Trait Anxiety Inventory (STAI) was used to assess the anxiety-related stress levels of 20 healthy participants. The participants installed a log-collecting application on their smartphones and answered the STAI questions once a day for one month. The proposed method showed an F-score of 74.2%, which is 4.0% higher than the F-score of previous studies (70.2%) that used single non-combined features. The results demonstrate that anxiety-related stress levels can be predicted using combined features extracted from smartphone log data.

Higher incidence of pancreatic fistula in laparoscopic gastrectomy. Real-world evidence from a nationwide prospective cohort study.

BACKGROUND: Laparoscopic distal gastrectomy (LDG) is becoming the standard procedure for gastric cancer. However, supporting evidence thus far has been derived primarily from randomized control trials conducted by centers of excellence. In the present study we used the National Clinical Database (NCD) in Japan to prospectively accumulate data from diverse types of hospitals and examine whether LDG is a safe and valid standard procedure. METHODS: From the NCD, 169 institutions were selected to form a cohort that was considered to be representative of Japan. From August 2014 to July 2015, 5288 patients who underwent LDG were registered prospectively, and clinical data were acquired through the NCD. To compare surgical outcomes between open distal gastrectomy (ODG) and LDG, we adjusted for confounding factors using propensity score matching, ultimately retrieving data from 1067 patients in each group. RESULTS: There were no significant differences in the number of in-hospital deaths in the ODG and LDG groups (3/1067 vs. 6/1067; P = 0.51) or in the number of reoperations (20/1067 vs. 29/1067; P = 0.19). However, the length of hospital stay was significantly shorter in the LDG. Although wound infection and dehiscence were more common in the ODG group, LDG was more often associated with grade B or higher pancreatic fistulas. CONCLUSION: The safety and minimal invasiveness of LDG were confirmed in the present Japanese nationwide survey. However, care must be taken to prevent the formation of pancreatic fistulas with LDG, and further improvements in surgical quality are warranted in this regard.

Bladder pressure monitoring and CO2 gas-related adverse events during per-oral endoscopic myotomy.

Per-oral endoscopic myotomy (POEM) is a minimally invasive treatment for esophageal achalasia. However, POEM has the potential risk of inducing carbon dioxide (CO2) gas-related adverse events, such as pneumoperitoneum, pneumomediastinum, and pneumothorax. The aim of this study was to evaluate the usability of bladder pressure monitoring as an index of CO2 gas-related pneumoperitoneum. The monitoring of bladder pressure and lung compliance and the incidence of iatrogenic pneumoperitoneum were retrospectively studied in 20 patients who underwent POEM between June 2013 and March 2015. The bladder pressure was measured using a Foley catheter. Abdominal distention was found in nine patients. The bladder pressure was significantly higher in the nine patients with the distention findings compared with patients without distention [7 (6-9) mmHg vs. 1 (0-2) mmHg; P < 0.05]; however, the decrease in dynamic lung compliance was not significantly different compared with patients without distention [- 7 (- 9.3 to - 5.1) vs. - 5 (- 10.2 to - 1.3) ml/cmH2O; P = 0.62]. Based on postoperative changes on CT scans; the following were the observations: pneumomediastinum (55%), minor pneumothorax (5%), pleural effusion (45%), atelectasis (15%), pneumoperitoneum (85%), and subcutaneous emphysema (15%). No significant clinical status was found among the patients postoperatively. Bladder pressure monitoring might be useful for detecting pneumoperitoneum during POEM.

[Distortion Reduction Effect of View Angle Tilting (VAT) in Large Field of View Magnetic Resonance Imaging].

With shortening of the gantry of magnetic resonance imaging (MRI) systems, large field-of-view (FOV) imaging has become difficult because static magnetic field nonuniformity and gradient magnetic field nonlinearity exacerbate geometric distortion of MR images. However, results of earlier studies have demonstrated that view angle tilting (VAT) can reduce severe image distortion attributable to local susceptibility effects of metals. Although VAT is usually applied to local magnetic field nonuniformity, in principle VAT is expected to correct distortion also for peripheral images in large-FOV MRI. Results from this phantom experiment using VAT with large-FOV verified the effectiveness of distortion correction. The experiment using VAT showed reduction of maximum distortion from 23.6 to -1.9 mm. Furthermore, results of a volunteer study confirmed the distortion correction capability of VAT: it reduced distortion and improved visibility of the anatomical structure. In conclusion, experimentally obtained results underscore VAT effectiveness for improving distortion in large-FOV MRI.

The Risk Factors for Refractory Fistula after Esophagectomy with Gastric Tube Reconstruction in Patients with Esophageal Cancer.

BACKGROUND/AIMS: Anastomotic leakage (AL) after esophagectomy is associated with high rates of postoperative morbidity and mortality. In cases with leakage, a refractory fistula (RF) is sometimes recognized after esophagectomy. The aim of this study was to evaluate the risk factors for RF after esophagectomy with gastric tube reconstruction. METHODS: This study enrolled 244 consecutive esophageal cancer patients who had undergone esophagectomy with gastric tube reconstruction. RF was defined as a noncurative anastomotic site-cutaneous fistula that had been present for more than 2 months. We evaluated the risk factors for RF. RESULTS: AL occurred in 30 patients (12.3%). There was one mortality case (0.4%) due to mediastinitis caused by AL in the present series. A multivariate analysis revealed that the subcutaneous route was an independent risk factor for AL (OR 4.42, 95% CI 1.42-13.8, p = 0.01), and that the subcutaneous route was an independent risk factor for RF (OR 13.30, 95% CI 2.50-71.30, p = 0.0024). CONCLUSION: The results of this retrospective study suggest that subcutaneous route was associated with an increased risk of RF after esophagectomy with gastric tube reconstruction. The preoperative identification of risk factors may contribute to the prevention of postoperative AL and RF.

Triclosan sutures for surgical site infection in colorectal cancer.

BACKGROUND: Among all procedures, surgical site infections (SSIs) in colorectal surgery continue to have the highest rate, accounting for 5%-45%. To prevent the bacterial colonization of suture material, which disables local mechanisms of wound decontamination, triclosan-coated sutures were developed. We assessed the effectiveness of triclosan-coated sutures used for skin closure on the rate of SSIs in colorectal cancer surgery. METHODS: Until August 2012, we used conventional methods for skin closure in colorectal cancer surgery at the Department of Gastroenterological Surgery, Fukuoka University Faculty of Medicine. Therefore, for the control group, we retrospectively collected surveillance data over a 1.5-y period. From September 2012, we began using triclosan-coated polydioxanone antimicrobial sutures (PDS plus) for skin and fascia closure. Hence, we collected data for the study group from September 2012 to October 2013. Differences in baseline characteristics and selection bias were adjusted using the propensity score-matching method. RESULTS: A total of 399 patients who underwent colorectal surgery were included in this study. There were 214 patients in the control group and 185 patients in the study group. Baseline patient characteristics were similar between the propensity score-matched groups. The incidence of SSIs was less in the study group. Multivariate logistic regression analysis showed that the site of the procedure, laparoscopic surgery, and using triclosan-coated sutures remained the independent predictors of SSIs. CONCLUSIONS: The use of triclosan-coated sutures was advantageous for decreasing the risk of SSIs after colorectal surgery.

A prospective analysis of GERD after POEM on anterior myotomy.

BACKGROUND: Peroral endoscopic myotomy (POEM) is an emerging, minimally invasive procedure capable of overcoming limitations of achalasia treatments, but gastroesophageal reflux disease (GERD) after POEM is of concern and its risk factors have not been evaluated. This prospective study examined GERD and the association of POEM with reflux esophagitis. METHODS: Achalasia patients were recruited from a single center. The pre- and postoperative assessments included Eckardt scores, manometry, endoscopy, and pH monitoring. RESULTS: Between September 2011 and November 2014, 105 patients underwent POEM; 70 patients were followed up 3 months after POEM. Postoperatively, significant reductions were observed in lower esophageal sphincter (LES) pressure [from 40.0 ± 22.8 to 20.7 ± 14.0 mmHg (P < 0.05)], LES residual pressure [from 22.1 ± 13.3 to 11.4 ± 6.6 mmHg (P < 0.05)], and Eckardt scores [from 5.7 ± 2.5 to 0.7 ± 0.8 (P < 0.05)]. Symptomatic GERD and moderate reflux esophagitis developed in 5 and 11 patients (grade B, n = 8; grade C, n = 3), respectively, and were well controlled with proton pump inhibitors. Univariate logistic regression analysis revealed integrated relaxation pressure was a predictor of ≥grade B reflux esophagitis. No POEM factors were found to be associated with reflux esophagitis. CONCLUSION: POEM is effective and safe in treating achalasia, with no occurrence of clinically significant refractory GERD. Myotomy during POEM, especially of the gastric side, was not associated with ≥grade B (requiring medical intervention) reflux esophagitis. Extended gastric myotomy (2-3 cm) during POEM is recommended to improve outcomes.

Peroral endoscopic myotomy for esophageal achalasia: outcomes of the first over 100 patients with short-term follow-up.

BACKGROUND: POEM is a recently developed achalasia treatment method, which combines the efficacy of surgical myotomy with the benefits of endoscopic procedures. Very few studies have focussed on the efficacy and usefulness of POEM in over 100 cases. METHODS: The first 100 adult patients treated according to standard POEM technique in a single center and followed up for 3 months were identified and included in this study (men 42; women 58; mean age 48.2 ± 18.8; range 9-91 years) The pre- and postoperative assessments included Eckardt scores, manometry, endoscopy, and monitoring pH. RESULTS: Mean operative time was 150.8 ± 49.3 min (75-370 min). Adverse events over Grade IIIb by the Clavien-Dindo classification were not encountered. The mean preoperative and postoperative lower esophageal sphincter pressures were 43.6 ± 26.2 and 20.9 ± 12.7 mmHg, respectively, indicating a statistically significant decrease after POEM (P < 0.05). The mean preoperative and postoperative integrated relaxation pressure values were 33.5 ± 15.2 and 15.3 ± 6.5 mmHg (P < 0.05). Furthermore, the Eckardt score significantly decreased from 5.9 ± 2.5 preoperatively to 0.8 ± 0.9 postoperatively (P < 0.05). Clinical success was documented in 99 % of the patients. Short-term outcomes after POEM were extremely good and independent of the age, type of achalasia, and previous treatment method. The percent of monitoring time with a pH < 4 was 25.6 % (22/86) in patients not on proton-pump inhibitors. Nine patients were diagnosed with symptomatic gastroesophageal reflux disease (GERD); patients with reflux esophagitis and symptomatic GERD improved with PPI treatment. CONCLUSIONS: Our results confirm the efficacy of POEM in a large patient series and support POEM as one of the first-line achalasia therapies in the near future.