Fabrication, Evaluation, and Multiscale Simulation of Piezoelectric Composites Reinforced Using Unidirectional Carbon Fibers for Flexible Motion Sensors.

Piezoelectric composite materials can convert mechanical energy into electrical energy, thus promoting battery-free motion-sensing systems. However, their substandard mechanical performance limits the capability of sensors developed using flexible piezoelectric materials. This study introduces a novel design strategy for preparing high-strength flexible piezoelectric composite materials comprising unidirectional carbon fiber-reinforced potassium sodium niobate (K0.5Na0.5NbO3) nanoparticle-filled epoxy resin (UDCF/KNN-EP). The fibers significantly improve the Young's modulus of UDCF/KNN-EP along the fiber direction, which reaches 282.5 MPa. Moreover, the composite exhibits excellent stretchability and piezoelectric response ( V pp ∼ 1.1 V ${V}_{{\mathrm{pp}}}\ \sim \ 1.1\ V$ ) in the cross-fiber direction under cyclic tensile loading. Multiscale finite element analysis is performed via simulation, which allows theoretical examination of the experimental results and the material's mechanical response mechanism. Finally, UDCF/KNN-EP is seamlessly incorporated into athletic gear and used to measure the impact caused by baseball catching and track footfall patterns. This study harnesses the superior strength of carbon fibers to enhance the durability and dependability of self-powered sensors without compromising flexibility in specific directions.

Indocyanine green fluorescence imaging via endoscopic nasal biliary drainage during laparoscopic deroofing of liver cysts.

Laparoscopic deroofing of liver cysts is widely accepted as the treatment of symptomatic huge liver cysts. As bile leakage is a common complication of this procedure, indocyanine green (ICG) imaging has played an active role in detecting intrahepatic biliary tract. However, infusion ICG imaging needs time rag after injection due to moving from bloodstream to bile, and also, additional injection is needed when the fluorescent imaging is not clear. To cover this weakness of ICG imaging, we first applied ICG imaging via 5-Fr endoscopic nasal biliary drainage (ENBD) during laparoscopic deroofing of liver cysts. This technique promptly gives us ICG imaging after ICG injection from ENBD; in addition, direct ICG imaging sometimes reveals minor leakage from sealing line and staple lines; therefore, we believe that direct ICG imaging via ENBD helps us to prevent post-operative bile leakage.

[Improved Neural Imaging Sequence and Comparison with Conventional Methods].

The purpose of this study was to improve the contrast between the nerves and blood by reconsidering the imaging parameters of the sampling perfection with application-optimized contrasts using different flip angle evolutions (SPACE) method, and to compare it with conventional methods, including the constructive interference in steady state (CISS) and T2-weighted SPACE (T2-SPACE) methods. In the phantom study, the repetition time (TR), echo time (TE), flip angle (FA), and turbo factor (TF) of SPACE were varied using the restore pulse. The parameters for which the nerve-blood contrast (C1) and cerebrospinal fluid-nerve contrast (C2) were equal were selected. Though multiple conditions resulted in C1 and C2 equivalence, we determined/set the TR=500 ms, TE=21 ms,  FA=120°, and  TF=30, considering the acquisition time, specific absorption rate (SAR), and artifacts. This sequence was called "short TR and short TE SPACE with restore pulse (SSSR)". In the phantom and healthy volunteer studies, the contrast between the nerves and blood in the SSSR method was statistically superior in both the physical and visual assessments compared with conventional methods. In the healthy volunteer study, C1 improved from 0.08 for CISS and 0.18 for T2-SPACE to 0.43 for SSSR. This is because the nerve signals in conventional methods were low due to the heavy T2-weighted, while those in the SSSR method were high due to the short TE and effect of the restore pulse. In conclusion, the contrast between the nerves and blood was significantly higher in the SSSR method compared with conventional methods.

Comparison of Single-Incision Laparoscopic Cholecystectomy versus Needlescopic Cholecystectomy: A Single Institutional Randomized Clinical Trial.

BACKGROUND: Both single-incision laparoscopic cholecystectomy (SILC) and needlescopic cholecystectomy (NSC) are superior to conventional laparoscopic cholecystectomy in terms of cosmetic outcome and incisional pain. We conducted a prospective, randomized clinical trial to evaluate the surgical outcome, postoperative pain, and cosmetic outcome for SILC and NSC procedures. METHODS: In this trial, 105 patients were enrolled (52 in the SILC group; 53 in the NSC group). A visual analogue scale (VAS) was used to evaluate the cosmetic outcome and incisional pain for patients. Logistic regression analyses were used to evaluate the operative difficulty that was present for both procedures. RESULTS: There were no significant differences in patient characteristics or surgical outcomes, including operative time and blood loss. The mean VAS scores for cosmetic satisfaction were similar in both groups. There were significant differences in the mean VAS scores for incisional pain on postoperative day 1 (p = 0.009), and analgesics were required within 12 h of surgery (p = 0.007). Obesity (body mass index ≥25 kg/m2) was the only significant influential factor for operating time over 100 min (p = 0.031). CONCLUSION: NSC is superior to SILC in terms of short-term incisional pain. Experienced laparoscopic surgeons can perform both SILC and NSC without an increase in operative time.

Retrospective case-matched study between reduced port laparoscopic rectopexy and conventional laparoscopic rectopexy for rectal prolapse.

INTRODUCTION: Reduced port laparoscopic Well's procedure (RPLWP) is a novel technique used to overcome the limitations of single-incision laparoscopic surgery. The aim of this study was to compare outcomes between RPLWP and conventional laparoscopic Well's procedure (CLWP) and to investigate the learning curve of RPLWP. PATIENTS AND METHODS: From January 2006 to March 2017, a retrospective review of a prospectively maintained laparoscopic surgery database was performed to identify patients had undergone CLWP and RPLWP. From these patients, each of 10 cases were manually matched for age, sex, body mass index. From January 2006 to March 2015, CLWP was used for all procedures whereas, from April 2015, RPLWP was routinely performed as a standard procedure for rectal prolapse. RESULTS: No significant differences were observed between the two groups in terms of operating time, blood loss, intraoperative complications, and conversion to CLWP or open rectopexy. Based on the postoperative outcomes, the hospital stay was significantly shorter in the RPLWP group. The estimated learning curve for RPLWP was fitted and defined as y = 278.47e-0.064x with R2 = 0.838; therefore, a significant decrease in operative time was observed by using the more advanced surgical procedure. CONCLUSIONS: RPLWP is an effective, safe, minimally invasive procedural alternative to CLWP with no disadvantage for patients when a skilled surgeon performs it.

[Exposure Dose Reduction for Radiologists with Combination of Angular Beam Modulation and Radiation Protection Drape in CT Fluoroscopy: A Phantom Study].

PURPOSE: To assess the dose reduction of radiologists by using angular beam modulation (ABM) and radiation protection drape during computed tomography (CT) fluoroscopy. MATERIALS AND METHODS: The phantom was set on the lower that is 15 cm from the isocenter position. We measured the radiation exposure around the phantom with radiophotoluminescence glass dosimeters. The space radiation dose rate was measured with an ionization chamber dosimeter in the CT room. RESULTS: The dose rate of finger radiation exposure was 67% at assumed assist tool position with ABM. And the dose rate of finger radiation exposure with the combination of ABM and radiation protection drape was 33%. The space dose rate of exposure with the combination of ABM and radiation protection drape was 49% at 150 cm. CONCLUSION: The combination of ABM and radiation protection drape can reduce finger radiation exposure at assumed assist tool position. The space dose rate of the standing position of radiologists can get a clear dose of radiation reduction by the combination of both.

[Injection Pressure Evaluation of the New Venous Catheter with Side Holes for Contrast-enhanced CT/MRI].

The simulation study was conducted for the new venous catheter with side holes of contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) to evaluate the infusion pressure on four contrast media and several injection speeds. All infusion pressure of the new venous catheter with side holes were less than 15 kg/cm2 as limitation of extension tube and also reduced the infusion pressure by 15% at the maximum compared to the catheter with single hole. The results suggest that the new venous catheter with side holes can reduce the infusion pressure by power injection of contrast-enhanced CT and MRI.

Comparison of Analytical Values in Diffusion Kurtosis Imaging among Different MRI Units.

Diffusion kurtosis imaging (DKI) is a method of analyzing restricted diffusion. Mean kurtosis (MK) is obtained from DKI. It is not known how different MRI scanners and coil systems will change MK when the same imaging parameters are used. The purpose of this study is to identify tendencies in MK when using various MRI scanners and coil systems. A total of 27 healthy volunteers were enrolled in this study. DKI was performed on the brain for each volunteer on five MRI scanner/coil system combinations using the same scan parameters. MK of 10 anatomical areas of the brain were compared, and the signal-noise ratios (SNRs) of b-2000 s/mm2 images were measured in identical areas. There were no significant differences among MKs from multi transmit (MT) MRI systems, but MK was significantly lower on the single transmit MRI system because of pepper artifact caused by low SNR. In conclusion, we found no significant differences in MK among MT systems, and MK was significantly lower without MT.

Effects of changes in adipocyte hormones and visceral adipose tissue and the reduction of obesity-related comorbidities after laparoscopic sleeve gastrectomy in Japanese patients with severe obesity.

The aim of this study was to evaluate the relative contribution of serum adipokines and adipokines from the patient's omentum-derived adipocytes (PODAs) and visceral adipose tissue (VAT) of Japanese patients with severe obesity. Secondarily, we analyzed patients' metabolic changes after laparoscopic sleeve gastrectomy (LSG). Twenty-three LSG patients and 23 non-obese patients undergoing elective abdominal surgery were enrolled. The levels of adipokines in the serum and the PODAs were measured. The clinical and metabolic data were evaluated at 6 months after LSG. The mean serum leptin levels and the mean serum plasminogen activator inhibitor type-1 (PAI-1) levels were significantly greater (p < 0.001) and the mean adiponectin levels were significantly lower in the LSG group (p = 0.006). In the measurements of the PODAs, the mean leptin levels (p < 0.001) were significantly greater and the mean adiponectin levels (p < 0.001) were significantly lower in the LSG group. The mean BMI (-12 kg/m², p < 0.001) and mean VAT (-135.5 cm², p = 0.001) were significantly decreased after LSG. In nine patients with type 2 diabetes mellitus, the reduction in VAT correlated with the change in high-sensitivity C-reactive protein (p = 0.006) and the homeostasis model of assessment of insulin resistance (p = 0.001). After 6 months, LSG markedly improved most obesity-related comorbidities. Our results suggest that LSG may contribute to VAT reduction, improved adipocyte hormone levels, and changes in gut physiology and endocrinology.

[Efficacy and safety of panitumumab for K-ras wild-type unresectable or recurrent colorectal cancer - a study focusing on first-line treatment].

Panitumumab was approved in June 2010 for use in the treatment of unresectable advanced/recurrent colorectal cancer. Here, we report outcomes and adverse events of panitumumab combination therapy or single-agent chemotherapy for K-ras wild-type unresectable or recurrent colorectal cancers. Our study focused on first-line treatments. The study involved 18 patients who started receiving panitumumab in October 2010. Nine patients received panitumumab as a first-line treatment; 4, as a second-line treatment; and 5, as a third-line or subsequent treatment. The overall response rate was 27.8%. Among the patients who received panitumumab as a first-line treatment, the response rate was 55.6%. Grade 1 and 2 skin disorders were common adverse events. Grade 2 interstitial pneumonia was observed in 1 patient(5.6%). Grade 3 or higher events comprised peripheral neuropathy in 1 patient(5.6%)and neutropenia in another patient(5.6%). The treatment was beneficial, and metastatic foci were resected in 3 patients. In this study, the only adverse events of Grade 3 or higher were 1 case each of peripheral neuropathy and neutropenia. Accordingly, adequate control seemed possible. The specific line of treatment that panitumumab should belong to remains controversial. However, active initiation as first-line treatment should be considered for cases in which resection of metastatic foci can be expected from tumor reductions due to panitumumab.

Assessment of first-time and repeated acute adverse reactions to gadolinium-based contrast agents in MRI: A retrospective study.

PURPOSE: To identify gadolinium-based contrast agents (GBCAs)-related and patient-related risk factors for acute adverse reactions (AARs), and to examine the incidence and severity of repeated AARs. METHODS: This study retrospectively evaluated all intravenous GBCA injections in MRI studies at a single institution from January 2012 to September 2019. First-time AARs in patients without a past history of AARs and risk factors were assessed using multivariable regression models with generalized estimating equations. For patients with a past history of AAR(s), we evaluated the incidence of repeated AARs using the Fisher's exact test, as well as the severity of these repeated AARs. RESULTS: First-time AARs occurred in 129 of 41,827 GBCA injections (0.31 %; 0.70 % of 18,431 patients). With gadoterate meglumine as the reference, the odds ratio (OR) for allergic-like reactions to three GBCAs ranged from 3.27 to 8.03 (p = 0.012 to <0.001). For chemotoxic reactions, the OR was 3.75 (p = 0.001) for gadoteridol. Outpatients had a lower OR for chemotoxic reactions, while higher ORs were observed in head/neck and breast MRI (p < 0.05). The OR for age was 0.99 (p < 0.05). Patients with a past history of AAR(s) had a 3.6 % incidence of mild repeated AARs for all GBCA, significantly higher than the 0.31 % in first-time AARs (p < 0.001). No effectiveness was found for steroid premedication. CONCLUSION: The occurrence of first-time AARs was related to the GBCA used and other factors. The incidence of repeated AARs was higher than first-time AARs, though all were mild in severity.

Optimization of 3D imaging time reduction by assessing spatial resolution in the slice selective direction using the ladder method.

PURPOSE: Assessing spatial resolution in MRI is challenging due to non-linearity. Despite the widespread use of 3D imaging in clinical practice for lesion detection and multi-planar reconstruction (MPR), the extended acquisition time poses a shortcoming. To address this, the "Slice resolution" parameter is utilized; however, its impact on MPR images is unclear. This study aims to assess spatial resolution using the ladder method, investigate the effects of diverse slice resolution settings in various imaging sequences, and propose optimal conditions. METHODS: Images were acquired using various 3D imaging sequences-SPACE T1WI, SPACE T2WI, and VIBE T1WI-with different slice resolutions. Axial cross-section images were acquired and reconstructed into coronal cross-sections. The ladder method was employed for objective evaluation, including spatial frequency analysis. Additionally, visual evaluation was conducted and compared with ladder method results. RESULTS: For three imaging sequences, the evaluated value of ladder method remained relatively constant from 100 % to 80 % slice resolution. However, the evaluated value decreased in low-spatial frequency for slice resolution below 70 %. CONCLUSIONS: Results from both ladder method and visual evaluations indicated image quality remained stable when the slice resolution was decreased to 80 %, potentially enabling a 20 % reduction in imaging time while preserving resolution in other cross-sections reconstructed by MPR.

Contrast-induced anaphylaxis: does it occur in the medical environment and is it being responded to appropriately?

PURPOSE: To analyze the appropriateness of primary response for anaphylaxis due to iodinated contrast media (ICM) or gadolinium-based contrast agents (GBCA). MATERIALS AND METHODS: This retrospective study included all patients in whom intravenous contrast agents (five types of ICMs and four types of GBCAs) were administered at our hospital between April 2016 and September 2021. For the patients who developed anaphylaxis, we obtained data on the time records of contrast injection, anaphylaxis onset, and intramuscular adrenaline (epinephrine) administration. RESULTS: Of the 76,555 ICM and 30,731 GBCA administrations, anaphylaxis occurred in 49 cases (0.05%), and in 48 cases (98.0%) the onset was within 30 min after administration with widely distributed times (median, 7.5 min; interquartile range, 4.5-10.8 min; max, 26 min). Intramuscular adrenaline administration was performed in 43 cases (87.8%), and this was done within five minutes after the onset in 37 cases (75.5%). Only in 24 cases (49.0%), there were time records of both the onset and adrenaline administration (if performed). CONCLUSION: Anaphylaxis occurred within 30 min after contrast injection in the majority of the cases, but times were widely distributed. Only in 75.5% of cases, appropriate primary treatment was performed, and the importance of keeping exact time records in patients' charts should be re-emphasized.

Clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis.

PURPOSE: To evaluate the clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis. METHODS: This retrospective study included all patients undergoing contrast-enhanced computed tomography (CT) with intravenous ICM administration (iopamidol, iohexol, iomeprol, iopromide, ioversol) at our hospital between April 2016 and September 2021. Medical records of patients who experienced anaphylaxis were reviewed, and the multivariable regression model using generalized estimating equations was employed to eliminate the effect of intrapatient correlation. RESULTS: Of the 76,194 ICM administrations (44,099 men [58 %] and 32,095 women; age, median, 68 years) to 27, 696 patients, anaphylaxis occurred in 45 cases in 45 different patients (0.06 % of administration and 0.16 % of patients), all with onset within 30 min after administration. Thirty-one (69 %) had no risk factors for ADRs, including 14 (31 %) who had previously used the same ICM that caused anaphylaxis. Thirty-one patients (69 %) had a history of ICM use without any ADRs. Four patients (8.9 %) received oral steroid premedication. The only factor associated with anaphylaxis was the type of ICM, with an odds ratio (OR) of 6.8 (p < 0.001) for iomeprol with iopamidol as a reference. No significant differences in OR of anaphylaxis were found for patients' age, sex, or premedication. CONCLUSION: The overall incidence of anaphylaxis due to ICM was very low. More than half of the cases had no risk factors for ADRs and had no ADRs on past ICM administration, although the ICM type was associated with a higher OR.

Comparison of olanexidine versus povidone-iodine as a preoperative antiseptic for reducing surgical site infection in both scheduled and emergency gastrointestinal surgeries: A single-center randomized clinical trial.

Aim: Surgical site infection (SSI) is one of the most common postoperative complications in gastrointestinal surgery. To clarify the superiority of 1.5% olanexidine, we conducted a randomized prospective clinical trial that enrolled patients undergoing gastrointestinal surgery with operative wound classes II-IV. Methods: To evaluate the efficacy of 1.5% olanexidine in preventing SSIs relative to 10% povidone-iodine, we enrolled 298 patients in each group. The primary outcome was a 30-day SSI, and the secondary outcomes were incidences of superficial and deep incisional SSI and organ/space SSI. In addition, subgroup analyses were performed. Results: The primary outcome of the overall 30-day SSI occurred in 38 cases (12.8%) in the 1.5% olanexidine group and in 53 cases (18.0%) in the 10% povidone-iodine group (adjusted risk ratio: 0.716, 95% confidence interval: 0.495-1.057, p = 0.083). Organ/space SSI occurred in 18 cases (6.1%) in the 1.5% olanexidine group and in 31 cases (10.5%) in the 10% povidone-iodine group, with a significant difference (adjusted risk ratio: 0.587, 95% confidence interval: 0.336-0.992, p = 0.049). Subgroup analyses revealed that SSI incidences were comparable in scheduled surgery (relative risk: 0.809, 95% confidence interval: 0.522-1.254) and operative wound class II (relative risk: 0.756, 95% confidence interval: 0.494-1.449) in 1.5% olanexidine group. Conclusion: Our study revealed that 1.5% olanexidine reduced the 30-day overall SSI; however, the result was not significant. Organ/space SSI significantly decreased in the 1.5% olanexidine group. Our results indicate that 1.5% olanexidine has the potential to prevent SSI on behalf of povidone-iodine.

Usefulness of simulation in optimizing imaging settings for pediatric technetium-99m-dimercaptosuccinic acid single-photon emission computed tomography.

PURPOSE: Technetium-99m (99mTc) dimercaptosuccinic acid (DMSA) single-photon emission computed tomography (SPECT) has been used to diagnose renal scarring. The Japanese Society of Nuclear Medicine recently revised the 'Consensus Guidelines for Pediatric Nuclear Medicine Examination.' In this study, we compared simulation data with actual data obtained using a pediatric phantom for 99mTc-DMSA examinations and evaluated the usefulness of simulations in determining the optimal acquisition conditions for SPECT images. METHODS: A SPECT quality assurance (QA) phantom study produced images with a renal-to-background 99mTc ratio of 283:1 kBq/ml. The projection data for the simulation were simulated using the simulation of imaging nuclear detectors. To compare the actual measurements and simulations, recovery factors were used for the SPECT QA phantom for image quality assessment. Defect contrast and visual evaluation using Scheffe's method of pairwise comparison were used for the pediatric kidney phantom. RESULTS: The optimal imaging settings using a kidney phantom required an acquisition time of more than 8 min. The maximum difference in the recovery coefficient between the simulation and actual measurement using the SPECT QA phantom was 6%. CONCLUSION: We showed that an acquisition time of more than 8 min was necessary for DMSA-SPECT. In addition, phantom simulations were approximately equivalent to the actual measurement data and the adaptability of simulations was confirmed.

Post-contrast Acute Kidney Injury Following Emergency Transcatheter Arterial Embolization for Uncontrollable Postpartum Hemorrhage.

The aim of this study was to investigate the incidence of post-contrast acute kidney injury (PC-AKI) in patients with uncontrollable postpartum hemorrhage undergoing emergency transcatheter arterial embolization (TAE). Data collected included patient characteristics, serum creatinine (SCr) level before and after TAE, iodine quantity of contrast media, time between computed tomography and TAE, diabetes mellitus, hemorrhage volume, and blood transfusion volume. For the diagnosis of PC-AKI, the criteria of the European Society of Urogenital Radiology Guidelines (version 10.0) were used. A total of 71 TAE procedures were performed over a 5-year period, and 47 patients met the inclusion criteria. Preprocedural renal function and change of SCr were positively correlated (P < .001), although no patients met the PC-AKI criteria and none showed renal impairment on the follow-up examination (95% upper confidence limit = 6.2%). Total iodine quantity was not correlated with SCr change. Postpartum hemorrhage was finally controlled in all 47 patients, and they were subsequently discharged. In conclusion, emergency TAE for patients with uncontrollable postpartum hemorrhage was a safe and effective procedure, not only in terms of bleeding-related and other outcomes but also with respect to the risk of PC-AKI.

Reliability of ultrasound hepatorenal index and magnetic resonance imaging proton density fat fraction techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy as the reference standard.

PURPOSE: To evaluate the reliability of ultrasound hepatorenal index (US-HRI) and magnetic resonance imaging proton density fat fraction (MRI-PDFF) techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy proton density fat fraction (MRS-PDFF) as the reference standard. MATERIALS AND METHODS: Fifty-two adult volunteers (30 men, 22 women; age, 31.5 ± 6.5 years) who had no history of kidney disease or viral/alcoholic hepatitis were recruited to undergo abdominal US, MRI, and MRS examinations. US-HRI was calculated from the average of three pairs of regions of interest (ROIs) measurements placed in the liver parenchyma and right renal cortex. On MRI, the six-point Dixon technique was employed for calculating proton density fat fraction (MRI-PDFF). An MRS sequence with a typical voxel size of 27 ml was chosen to estimate MRS-PDFF as the gold standard. The data were evaluated using Pearson's correlation coefficient and receiver operating characteristic (ROC) curves. RESULTS: The Pearson correlation coefficients of US-HRI and MRI-PDFF with MRS-PDFF were 0.38 (p = 0.005) and 0.95 (p<0.001), respectively. If MRS-PDFF ≥5.56% was defined as the gold standard of fatty liver disease, the areas under the curve (AUCs), cut-off values, sensitivities and specificities of US-HRI and MRI-PDFF were 0.74, 1.54, 50%, 91.7% and 0.99, 2.75%, 100%, 88.9%, respectively. The intraclass correlation coefficients (ICCs) of US-HRI and MRI-PDFF were 0.70 and 0.85. CONCLUSION: MRI-PDFF was more reliable than US-HRI in diagnosing hepatic steatosis.