Comparison of the Outcomes of Total Endovascular Aortic Arch Repair Between Branched Endograft and Chimney Endograft Technique in Zone 0 Landing.

PURPOSE: Zone 0 landing in thoracic endovascular aortic repair (TEVAR) has recently gained increasing attention for the treatment of high-risk patients. The aim of this study was to compare the outcomes of total endovascular aortic arch repair between branched TEVAR (bTEVAR) and chimney TEVAR (cTEVAR) in the landing zone (LZ) 0. MATERIALS AND METHODS: This was a single-center, retrospective, and observational cohort study. From January 2010 to March 2020, 40 patients (bTEVAR, n=25; cTEVAR, n=15; median age: 79 years) were enrolled in this study, with a median follow-up period of 4.1 years. These patients were considered unsuitable for open surgical treatment. RESULTS: All procedures were successful and no cases of conversion to open repair were noted during the 30-day postoperative period. The 30-day mortality was 2.5% (n=1; bTEVAR [0 of 25, 0%] vs cTEVAR [1 of 15, 6.7%]; p=0.375), the perioperative stroke rate was 10.0% (n=4; bTEVAR [4 of 25, 16.0%] vs cTEVAR [0 of 15, 0%], p=0.278), and type 1a endoleak rate was 15.0% (n=6; bTEVAR [0 of 25, 0%] vs cTEVAR [6 of 15, 40.0%], p=0.001). The risk factor for stroke was atheroma grade of ≥2 in the brachiocephalic artery (p<0.001). The risk factor for type 1a endoleak was cTEVAR (p=0.001). The 8-year survival rate was 49.9%. The aorta-related death-free rate and aortic event-free rate at 8 years were 94.4% (bTEVAR: 95.5% vs cTEVAR: 93.3%, p=0.504) and 60.7% (bTEVAR: 70.7% vs cTEVAR: 40.0%, p=0.048), respectively. CONCLUSIONS: Total endovascular aortic arch repair using bTEVAR and cTEVAR is feasible for the treatment of aortic arch diseases in high-risk patients who are unsuitable for open surgery. However, as the rate of stroke is high, strict preoperative evaluation to prevent stroke is needed. No rupture of the aneurysm was observed in cTEVAR, but patients should be selected carefully because of the high incidence of type 1a endoleak.

Impact of the Patency of Inferior Mesenteric Artery on 7-Year Outcomes After Endovascular Aneurysm Repair.

PURPOSE: The impact of preoperative patent inferior mesenteric artery (IMA) on late outcomes following endovascular aneurysm repair (EVAR) remains unclear. This study aimed to investigate the specific influence of IMA patency on 7-year outcomes after EVAR. MATERIALS AND METHODS: In this retrospective cohort study, 556 EVARs performed for true abdominal aortic aneurysm cases between January 2006 and December 2019 at our institution were reviewed. Endovascular aneurysm repairs performed using a commercially available device with no type I or type III endoleak (EL) during follow-up and with follow-up ≥12 months were included. A total of 336 patients were enrolled in this study. The cohort was divided into the patent IMA group and the occluded IMA group according to preoperative IMA status. The late outcomes, including aneurysm sac enlargement, reintervention, and mortality rates, were compared between both groups using propensity-score-matched data. RESULTS: After propensity score matching, 86 patients were included in each group. The median follow-up period was 56 months (interquartile range: 32-94 months). The incidence of type II EL at discharge was 50% in the patent IMA group and 19% in the occluded IMA group (p<0.001). The type II EL from IMA and lumbar arteries was significantly higher in the patent IMA group than in the occluded IMA group (p<0.001 and p=0.002). The rate of freedom from aneurysm sac enlargement with type II EL was significantly higher in the occluded IMA group than in the patent IMA group (94% vs 69% at 7 years; p<0.001). The rate of freedom from reintervention was significantly higher in the occluded IMA group than in the patent IMA group (90% vs 74% at 7 years; p=0.007). Abdominal aortic aneurysm-related death and all-cause mortality did not significantly differ between groups (p=0.32 and p=0.34). CONCLUSIONS: Inferior mesenteric artery patency could affect late reintervention and aneurysm sac enlargement but did not have a significant impact on mortality. Preoperative assessment and embolization of IMA might be an important factor for improvement in late EVAR outcomes. CLINICAL IMPACT: The preoperative patency of the inferior mesenteric artery was significantly associated with a higher incidence of sac enlargement and reintervention with type II endoleak following endovascular aneurysm repair, even after adjustment for patient background. Preoperative assessment and embolization of inferior mesenteric artery might be an important factor for improvement in late EVAR outcomes.

Effectiveness of Proximal Landing Zones 0, 1, and 2 Hybrid Thoracic Endovascular Aortic Repair: A Single Centre 12 Year Experience.

OBJECTIVE: Hybrid thoracic endovascular aortic repair (TEVAR) is being accepted increasingly as a first line treatment for arch repair at the present authors' institution. This study aimed to clarify the effectiveness of zones 0, 1, and 2 landing hybrid TEVAR. METHODS: This was a retrospective single centre case series. From April 2008 to March 2020, 348 patients (median age 72 years; interquartile range [IQR] 65, 77 years) were enrolled, with a median follow up period of 5.6 years (IQR 2.6, 8.7 years). The procedures included zone 0 in 135 patients (38.8%), zone 1 in 82 patients (23.6%), and zone 2 proximal landing zone (LZ) hybrid TEVAR in 131 patients (37.6%). The pathologies consisted of dissecting aortic aneurysms in 123 (35.3%) patients. Emergency procedures were performed in 39 (11.2%) patients. RESULTS: The 30 day mortality (n = 2, 0.6%) and hospital deaths (n = 6, 1.7%) were registered. The stroke rate was 1.1% (n = 4), while early and late endoleak rates were 4.8% (n = 17) and 1.7% (n = 6), respectively. Type 1a endoleak and retrograde type A dissection occurred in seven (2.0%) and three (0.9%) patients, respectively. The cumulative survival, freedom from aorta related deaths, and freedom from aortic events in 10 years were 75.0%, 97.2%, and 84.1%, respectively. The freedom from aortic events in each landing zone in 10 years was 82.3%, 81.4%, and 87.9% for zones 0, 1, and 2, respectively. The 10 year survival rates were 82.5% and 73.6%; the 10 year aorta related death free rates were 94.9% and 98.6%, and the 10 year aortic event free rates were 82.3% and 85.5% in the zone 0 and zone 1 and 2 TEVAR, respectively. CONCLUSION: Satisfactory early and long term results of hybrid arch repair at zones 0, 1, and 2 were achieved. To avoid complications and aortic events, the treatment strategy of hybrid arch repair for aortic arch pathologies should be tailored using accurate pre-operative assessment of the ascending aorta and the aortic arch.

Risk Analysis of Aneurysm Sac Enlargement Caused by Type II Endoleak after Endovascular Aortic Repair.

BACKGROUND: Although the preoperative risk factors associated with the occurrence of type II endoleak (ETII) after endovascular aortic repair (EVAR) have gradually become more evident, the preoperative risk factors associated with aneurysm sac enlargement caused by ETII remain unclear. This study aimed to determine the preoperative risk factors associated with aneurysm sac enlargement caused by ETII after EVAR. METHODS: This retrospective cohort study reviewed 519 EVARs performed for true abdominal aortic aneurysm between January 2006 and December 2018 at our institution. EVARs using commercially available bifurcated devices with no type I or III endoleaks during follow-up and with ≥12 months follow-up were included. A total of 320 patients were enrolled in the study. To identify the preoperative risk factors of sac enlargement after EVAR, Cox regression analysis was used to assess preoperative data. RESULTS: The median follow-up period was 60.8 months. Overall, 135 of 320 patients (42%) had ETII during follow-up, and 47 of 135 patients (35%) developed aneurysm sac enlargement. Multivariate analysis revealed that chronic kidney disease (CKD) stage ≥4 (hazard ratio [HR], 4.65; 95% confidence interval [CI], 2.13-10.15; P = 0.001), patent inferior mesenteric artery (IMA) (HR, 17.85; 95% CI, 2.46-129.73; P< 0.001), and number of patent lumbar arteries (LAs) (HR, 1.37; 95% CI, 1.13-1.68; P= 0.002) were risk factors of aneurysm sac enlargement caused by ETII. CONCLUSIONS: CKD stage ≥4, patent IMA, and number of patent LAs were independent risk factors for aneurysm sac enlargement after EVAR. In particular, patent IMA had the highest HR and seemed to have the greatest impact on long-term aneurysm sac enlargement. Hence, taking preoperative measures to address a patent IMA appears to be important in reducing the incidence of sac enlargement.

Successful Hybrid Zone 0 Landing Thoracic Endovascular Aortic Repair for Ascending Aortic Pseudoaneurysm after Bentall Procedure and Coronary Artery Bypass Grafting in Takayasu Arteritis.

Pseudoaneurysm at the suture line is one of the most common complications in aortic surgery for Takayasu arteritis (TA) and is associated with a high mortality rate. A 52-year-old man with TA, who previously underwent the Bentall procedure and 2 redo surgeries for coronary artery obstruction and a pseudoaneurysm of a coronary button, was diagnosed with an anastomotic pseudoaneurysm in the ascending aorta. Hybrid zone 0 debranching thoracic endovascular aortic repair was performed, and the patient was discharged uneventfully on postoperative day 8.

[Adjuvant hormonal treatment for estrogen receptor-positive breast cancer-a questionnaire survey conducted by Japanese breast cancer society-authorized facilities in Hokkaido].

According to the Japanese Breast Cancer Society national breast cancer registration, 71.8%of breast cancer cases reported in 2004 and 79.8% of cases reported in 2010 were estrogen receptor(ER)positive. The frequency of ER-positive breast cancer is increasing annually in Japan. Many clinical trials have proven that adjuvant hormonal treatment affects both progression- free survival and overall survival in ER-positive breast cancer cases. However, some clinical questions remain, including those regarding the definition of preoperative hormonal treatment, appropriate dosage period, and therapeutic drug choice. In January 2013, we conducted a questionnaire survey of 53 medical doctors engaged in breast cancer treatment at 15 Japanese Breast Cancer Society-authorized facilities in Hokkaido. This survey included 6 clinical questions about preoperative hormonal treatment, 5 clinical questions about postoperative hormonal treatment for premenopausal breast cancer, and 4 clinical questions about postoperative hormonal treatment for postmenopausal breast cancer. We obtained replies from 35 medical doctors at 27 facilities. The response rate was 66%. We accumulated and analyzed these data. The discussion of questionnaire results in the medical administration field facilitates the sharing of information regarding differences in the approaches of different facilities to breast cancer patients. As a result, standardization of the breast cancer medical treatment system in this area has been accomplished.

[Prognosis of Papillary Thyroid Carcinoma with Local Invasion].

OBJECTIVE: The aim of this study was to detect prognostic factors in patients with locally advanced papillary thyroid carcinoma. PATIENTS: The study included 72 patients (T4a/T4b 72/0, N0/N1a/N1b 25/15/32, M0/M1 68/4, mean follow-up 8.1 4.4 years) who underwent initial surgical treatment at Osaka Red Cross Hospital between April 1993 and April 2011. RESULTS: Eleven patients died of PTC, 3 patients with recurrence died of unrelated disease and 10 patients are alive with recurrence. The overall 5-year survival rate was 88.3%, and the 10-year survival rate was 73.4%. The disease-specific 5-year survival rate was 91.4%, and the 10-year survival rate was 88.6%. The 5-year local control rate was 94.1%, and the 10-year local control rate was 85.4%. Patients with distant metastasis (M1), tracheal invasion and/or multiple organs invasion showed a significantly worse disease-specific survival rate based on a univariate analysis, which also revealed that tracheal invasion, laryngeal invasion, esophageal invasion and multiple organs invasion were risk factors linked to the development of distant metastasis during follow-up (recurrence as distant metastasis). The following were found to be clinically significant risk factors, based on the multivariate analysis among tracheal invasion, laryngeal invasion, esophageal invasion and recurrent laryngeal nerve invasion : Tracheal invasion was a risk factor for disease-specific survival, and tracheal invasion and laryngeal invasion were risk factors for recurrence as distant metastasis. CONCLUSIONS: In this study, distant metastasis, multiple organs invasion, tracheal invasion and/or laryngeal invasion were shown to be higher risk factors.

Hybrid endovascular repair of a dissecting thoracoabdominal aortic aneurysm with stent graft implantation through the false lumen.

We report the first successful hybrid endovascular technique for treating a residual dissecting thoracoabdominal aortic aneurysm with a compressed true lumen in a 48-year-old man in whom multiple stent grafts were deployed through the false lumen. The first stage of the procedure involved debranching of the visceral vessels from the right external iliac artery. In the second stage, a Gore excluder iliac extender (W. L. Gore and Associates, Flagstaff, Ariz) was deployed through the false lumen of the left common iliac artery; then, a Powerlink bifurcated stent graft (Endologix, Irvine, Calif) was positioned at the false lumen of the abdominal aorta. Overlapping with this stent graft, three Gore TAG stent grafts were deployed upward toward the Dacron (DuPont, Wilmington, Del) graft implanted during a previous operation on the descending aorta. Subsequently, the patient had an uneventful postoperative course, with no complications at the 3-year follow-up. The successful results of our new hybrid endovascular technique suggest the feasibility and efficacy of stent graft implantation through the false lumen.

Aortic remodeling as a prognostic factor for late aortic events after thoracic endovascular aortic repair in type B aortic dissection with patent false lumen.

PURPOSE: To assess the significance of aortic remodeling in the prevention of the late aortic events after thoracic endovascular aortic repair (TEVAR) for aortic dissection. METHODS: The study involved 52 patients (41 men; mean age was 59.7±13.3 years) with type B aortic dissections and patent false lumens treated with TEVAR between 2004 and 2011. Of the 52 patients, 18 were treated in the acute phase for rupture (n=1), malperfusion (n=10), aortic diameter over 40 mm at onset (n=3), and rapid enlargement of the false lumen (n=4). In the chronic setting, the indications for TEVAR were rupture (n=1), malperfusion (n=2), aortic diameter >50 mm (n=18), and rapid enlargement of the false lumen (n=13). Aortic remodeling was evaluated at 6 months postoperatively, and risk factors for late aortic events were evaluated in multivariate analysis using aortic remodeling and other pre-, peri-, and postoperative factors. RESULTS: Over a mean 36.0±18.9 months, 19 aortic events were documented: enlargement of the false lumen (n=4), type I endoleak (n=2), and erosion at the stent-graft edges (n=13). Multivariate analysis revealed that failure to achieve aortic remodeling at 6 months postoperatively was the only significant risk factor for late aortic events (hazard ratio 0.20, p=0.037). Patients with aortic remodeling had a higher rate of freedom from aortic events compared with those without aortic remodeling (100% vs. 81.5% at 1 year and 79.3% vs. 48.4% at 3 years, respectively). CONCLUSION: Aortic remodeling after TEVAR is a significant prognostic factor for better long-term results for type B aortic dissection.

A multi-institutional retrospective study of 340 cases of sinonasal malignant tumor.

OBJECTIVE: Sinonasal malignant tumors (SNMT) are relatively rare among head and neck malignant tumors. Most are squamous cell carcinomas, and malignant melanomas, olfactory neuroblastomas, adenoid cystic carcinomas, sarcomas, and others also occur. The most common primary site of nasal sinus squamous cell carcinoma is the maxillary sinus. In recent years, a decrease in incidence of maxillary sinus squamous cell carcinoma (MSSCC) has been reported along with a decrease in the incidence of sinusitis. MSSCC is treated with a combination of surgery, radiation, and chemotherapy. Treatment decisions are made according to the progression of the disease, the patient's general condition, and the patient's own wishes. There are variations in treatment policies among facilities due to the specialty of staff and cooperation with other departments at each facility. We conducted a multi-institutional retrospective study to compare outcomes by treatment strategy. METHODS: In this study, 340 patients with SNMT who were treated at 13 Hospitals (Head and Neck Oncology Group (Kyoto-HNOG) ) during the 12-year period from January 2006 to December 2017 were included. There were 220 patients with squamous cell carcinoma, 32 with malignant melanoma, 21 with olfactory neuroblastoma, and 67 with other malignancies. Of the squamous cell carcinomas, 164 were of maxillary sinus origin. One hundred and forty cases of MSSCC that were treated radically were included in the detailed statistical analysis. RESULTS: There were 5 cases of cStage I, 9 cases of cStage II, 36 cases of cStage III, 74 cases of cStage IVa, and 16 cases of cStage IVb. There were 92 cases without clinical lymph node metastasis (cN(-)) and 48 cases with clinical lymph node metastasis(cN(+)). Primary tumors were treated mainly by surgery in 85 cases (Surg) and by radical radiation therapy (with or without chemotherapy) of 6-70 Gy in 55 cases(non-Surg). The 5-year overall/disease-free survival rate (OS/DFS) for MSSCC was 65.1%/51.6%. Old age, renal dysfunction, and clinical T progression were independent risk factors for OS, and renal dysfunction was an independent risk factor for DFS. In cN(-) patients, OS and DFS were significantly better in Surg group than in non-Surg group. In cN(+) patients, there was no significant difference in OS and DFS between Surg and non-Surg groups. CONCLUSION: For patients with MSSCC without lymph node metastasis, aggressive surgery on the primary tumor contributes to improved prognosis.

Impact of cervical lymph node metastasis on transoral surgery for hypopharyngeal squamous cell carcinoma: A retrospective multicenter study.

BACKGROUND: Hypopharyngeal carcinoma is likely to spread to the lymph nodes, but there is no established strategy for management in transoral surgery. METHODS: We compared oncologic and functional outcomes in a retrospective multicenter study of patients who underwent transoral surgery for hypopharyngeal carcinoma between 2015 and 2021. RESULTS: Two-hundred and thirty-two patients were included. Comparing patients with and without adjuvant radiotherapy, 3-year regional recurrence-free survival (RRFS) was not significantly different in pN2b and pN2c, but was significantly worse in pN3b without adjuvant radiotherapy. In patients without neck dissection, the 3-year RRFS was 85.6%, 76.8%, and 70.0% for T1, T2, and T3 primary lesions, respectively, and was significantly worse for T2 or higher (p = 0.035). CONCLUSIONS: In the absence of extracapsular invasion, regional control did not deteriorate without adjuvant therapy. If prophylactic neck dissection is not performed, careful follow-up is necessary if the primary lesion is T2 or greater.

Complications including dysphagia following transoral non-robotic surgery for pharyngeal and laryngeal squamous cell carcinoma: A retrospective multicenter study.

OBJECTIVE: Transoral surgery is a minimally invasive treatment but may cause severe dysphagia at a lower rate than chemoradiotherapy. METHODS: We compared clinical information, surgical complications, and swallowing function in patients who underwent transoral nonrobotic surgery for laryngo-pharyngeal squamous cell carcinoma between 2015 and 2021 in a multicenter retrospective study. RESULTS: Six hundred and forty patients were included. Postoperative bleeding was observed in 20 cases (3.1%), and the risk factor was advanced T category. Postoperative laryngeal edema was observed in 13 cases (2.0%), and the risk factors were prior radiotherapy, advanced T stage, and concurrent neck dissection in patients with resected HPC. Dysphagia requiring nutritional support was observed in 29 cases (4.5%) at 1 month postoperatively and in 19 cases (3.0%) at 1 year postoperatively, respectively. The risk factors for long-term dysphagia were prior radiotherapy and advanced T category. Short-term risk factors for dysphagia were prior radiotherapy, advanced T category, and concurrent neck dissection, while long-term risk factors for dysphagia were only prior radiotherapy and advanced T category. CONCLUSION: Prior radiotherapy, advanced T stage, and concurrent neck dissection increased the incidence of postoperative laryngeal edema and short-term dysphagia, but concurrent neck dissection did not affect long-term dysphagia. Such features should be considered when considering the indication for transoral surgery and postoperative management.

Local recurrence and metachronous multiple cancers after transoral nonrobotic surgery for pharyngeal and laryngeal squamous cell carcinoma: A retrospective multicenter study.

BACKGROUND: Late laryngopharyngeal cancers after transoral surgery include not only local recurrences but also metachronous multiple cancers. METHODS: We compared clinical information, surgical outcomes, and late laryngopharyngeal cancers in patients who underwent transoral nonrobotic surgery for laryngopharyngeal squamous cell carcinoma without lymph node metastases between 2015 and 2021 in a multicenter retrospective study. RESULTS: Four hundred and fifty-seven patients were included. Positive surgical margins were found in 121 patients (26.5%). Twenty-two patients (4.8%) received additional treatment. Positive horizontal margins of invasive carcinoma (p = 0.003) and positive horizontal margins of carcinoma in situ only (p = 0.032) were independent risk factors for local recurrence, and prior radiotherapy (p = 0.001) for metachronous multiple cancers. Local control was significantly worse without additional treatment (p = 0.049), but there was no significant difference in survival. CONCLUSIONS: Patients with positive margins had an increased frequency of local recurrence, but salvage therapy was effective.

A new staged hybrid total arch repair procedure using a branched proximal elephant trunk technique with implantation of stent grafts to the ascending aorta.

We report a new hybrid aortic arch repair procedure for the treatment of extensive thoracic aortic aneurysms involving the ascending aorta, arch, and descending aorta. In the first stage of this procedure, a "double-barrel tube graft" was inserted into the ascending aorta and fixed to the sinotubular junction under short-duration cardiopulmonary bypass in normothermia. In the next stage, after debranching of the left common carotid artery and left subclavian artery, stent grafts were deployed from the double-barrel tube graft to the descending aorta and the brachiocephalic artery to exclude the aneurysms. The patient's postoperative course was uneventful, with no endoleaks. The successful initial result suggests that this procedure could be an attractive treatment option for extensive aortic aneurysms.

Size- and orientation-selective encapsulation of C(70) by cycloparaphenylenes.

The size- and orientation-selective formation of the shortest-possible C70 peapod in solution and in the solid state by using the shortest structural unit of an "armchair" carbon nanotube (CNT), cycloparaphenylene (CPP), has been studied. [10]CPP and [11]CPP exothermically formed 1:1 complexes with C70 , thereby giving the resulting peapods. A van't Hoff plot analysis revealed that the formation of these complexes in 1,2-dichlorobenzene was mainly driven by entropy, whereas the theoretical calculations suggested that the formation of the complex in the gas phase was predominantly driven by enthalpy. C70 was found to exist in two distinct orientations inside the CPP cavity, namely "lying" and "standing", depending on the specific size of the CPP. The theoretical calculations and the X-ray crystallographic analysis revealed that the interactions between [10]CPP and the short axis of C70 in its lying orientation were isotropic and similar to those observed between [10]CPP and C60 . However, the interactions between [11]CPP and C70 in its standing orientation were anisotropic, thereby involving the radial deformation of [11]CPP into an ellipsoidal shape. This "induced fit" maximized the van der Waals interactions with the long axis of C70 . Theoretical calculations revealed that the deformation occurred readily with low energy loss, thus suggesting that CPPs are highly radially elastic molecules. These results also indicate that the same type of radial deformation should occur in CNT peapods that encapsulate anisotropic fullerenes.

[Two cases of multiple liver metastases breast cancer successfully treated with combination chemotherapy by S-1, vinorelbine and medroxyprogesterone].

We report our experience with two cases of postoperative multiple liver metastases that were reduced remarkably by S-1, VNR, and MPA combination therapy for breast cancer. A case diagnosed as Stage II B(T2, N1, M0)breast cancer was treated postoperatively with LH-RH agonist and TAM. Another case, diagnosed as Stage III B(T4b, N2, M0), was treated with postoperative CE therapy. Tumor markers were normalized and liver metastases were shrunk significantly in both cases which received combination chemotherapy of S-1, VNR, and MPA as first-line therapy after recurrence. We conclude that this combination chemotherapy is a useful regimen for metastatic breast cancer patients, because it can be continuously implemented over a long period of time while maintaining high QOL without serious adverse events.

Electron Transfer Reduction by Hydrogen Creates Porosity in Tantalate Crystals and Produce Multifunctionality.

Contrary to partially substituted systems, WO3 molecular sieves that exclusively comprise a d0 transition metal ion and do not possess template ions in the cavity are a new class of materials for photocatalysis owing to their framework structure. Because WO3 thermodynamically lacks proton-reduction capability, exploring diverse synthetic approaches of other materials is desirable for facilitating utilization as H2 evolution and water splitting systems. Herein, we report an efficient approach for the protonation of Ag2Ta4O11 to afford H2Ta4O11 for application as a H2 molecular sieve. Hydrogen reduction of Ag2Ta4O11 at 300 °C and post-treatment using HNO3 afforded H2Ta4O11. Characterizations of H2Ta4O11, coupled with density functional theory (DFT) calculations, reveal that the intrinsic structure of Ag2Ta4O11 is maintained. Moreover, H+ is generated from H2 oxidation and forms OH, and the orientation of OH is parallel to that of the ab plane. Desorption and adsorption of H2 within H2Ta4O11 were achieved by heating H2Ta4O11 to above 90 °C. This is attributed to positive thermal expansion, as confirmed by high-temperature X-ray diffraction. H2Ta4O11 is an active heterogeneous photocatalyst for the half-reactions of water splitting. Moreover, deuteration experiments of H2Ta4O11 in D2O suggest its capability as a H2-D2 conversion catalyst. Furthermore, H2Ta4O11 functions as an active synthetic precursor for new tantalate materials, the direct synthesis of which is challenging.

Delayed Right Ventricular Pacemaker Lead Perforation 9 Years After Implantation.

BACKGROUND Cardiac perforation is a rare complication of cardiac implantable electronic devices, with a reported incidence ranging from 0.1% to 5.2%. Delayed perforation, defined as perforation occurring more than 1 month after implantation, is more uncommon. In this report, we present a case of cardiac perforation involving the right ventricle wall that occurred 9 years after pacemaker implantation. CASE REPORT A 79-year-old woman presented with symptoms of dyspnea and was subsequently admitted to a hospital. She had undergone pacemaker implantation for a complete atrioventricular block 9 years prior to the presentation. The patient had right ventricular failure to capture and a resultant complete atrioventricular block. Computed tomography imaging revealed that the right ventricular lead had clearly protruded outside the heart; however, no pericardial effusion was observed. When the patient underwent open surgical repair, the ventricular tined lead was noted to be traversing the right ventricular apex. Device interrogation revealed a sudden increase followed by a gradual decrease in the right ventricular pacing threshold over the course of 2 months, indicating that the lead had slowly traversed the right ventricular muscle before ultimately rupturing through it. CONCLUSIONS This study described the case of a delayed right ventricular pacemaker lead perforation that occurred 9 years after implantation, which was managed via open surgical repair.

Deep learning for hetero-homo conversion in channel-domain for phase aberration correction in ultrasound imaging.

Echo imaging in ultrasound computed tomography (USCT) using the synthetic aperture technique is performed with the assumption that the speed of sound is constant in the system. However, tissue heterogeneity causes a mismatch between the predicted arrival time and the actual arrival time of the echo signal, which will result in phase aberration, leading to the quality degradation of the reconstructed B-mode image. The conventional correction methods that use the correlation of each different channel require the presence of strong point scatterers and involve the problem of local solutions due to excessive correction. In this study, we propose a novel approach to correcting the signal distortion due to sound speed heterogeneity using a deep neural network (DNN). The DNN was trained to convert the distorted radio frequency (RF) inputs for the heterogeneous medium to the distortion-free RF outputs for the homogeneous medium. The network with U-net architecture using ResNet-34 as a backbone was trained using the hetero-homo corresponding channel-domain RF data generated via numerical simulations. The trained network performed phase aberration correction in the channel-domain RF, with the B-mode images reconstructed with the corrected RF demonstrating a higher contrast and an improved resolution compared with uncorrected cases. It was also demonstrated that the DNN model is robust to both varied reflection intensities and varied sound speed heterogeneities. The successful results demonstrated that the proposed DNN-based method is effective for phase aberration correction in US imaging.