Early results of transcatheter electrosurgical aortic septotomy for endovascular repair of chronic dissecting aortoiliac aneurysms

Objective

Endovascular repair of chronic dissecting aortoiliac aneurysms is challenging given the rigid septum, compressed true lumen (TL), and target vessels frequently originating in the false lumen. We have used transcatheter electrosurgical aortic septotomy (TEAS) before stent graft implantation under intravascular ultrasound (IVUS) and fusion guidance. The purpose of this study is to assess the outcomes of TEAS during complex endovascular repair of dissecting aneurysms.

Methods

From 2021 to 2023, 17 patients underwent TEAS. The primary end point was technical success, with secondary end points of proximal and distal seals, target vessel instability, aortic and iliac TL and cross-sectional area (CSA) expansion, and aortic-related death. During the procedure, the aortic septum is crossed through a pre-existing entry or via electrocautery-activated 0.018-in. Astato XS20 wire (Asahi-Intecc) under IVUS and fusion guidance. The penetrated wire is then snared in the false lumen and pulled through the ipsilateral femoral access. A 1-cm length of the middle of the Astato wire coating is kinked in a three-sided polygonal configuration, denuded the inner surface of the wire using a no. 15 blade, and positioned at the apex of the septum. Both ends of the Astato wire are insulated with 0.018-in. microcatheters, and the back end of the wire is denuded and connected to cautery. Gentle traction is applied to the wire, and short bursts of electrocautery cutting are applied at 60 to 80 W.

Results

The technical success of the septotomy was 100%. No incidence of visceral or lower extremity malperfusion, vascular injury, or distal embolization occurred. Of the 17 patients, 4 underwent thoracic endovascular aneurysm repair, 2 underwent endovascular aortic repair, and 11 underwent fenestrated/branched endovascular aneurysm repair after septotomy. All target vessels were successfully stented. A distal landing zone seal with exclusion of the false lumen was achieved in 16 of the 17 patients (94.1%). One patient required embolization of the false lumen of the celiac artery after septotomy. The TL mean diameter and CSA of the descending thoracic aorta after septotomy was expanded by 7.01 ± 1.9 mm (relative mean diameter expansion, 42.3%; P < .0001) and 2.71 ± 0.4 cm2 (relative mean CSA expansion, 57.3%, P<.0001). For patients who required septotomy through the common iliac arteries, the mean TL was expanded by 8.1 ± 3.7 mm (relative mean diameter expansion, 76%; P < .0001) and 1.76 ± 0.91 cm2 (relative mean CSA expansion, 209%; P < .0001). The 1-year freedom from target vessel instability was 91%.

Conclusions

The use of IVUS and fusion-guided TEAS offers a promising technique to facilitate TL expansion and false lumen exclusion in chronic dissecting aortic aneurysms before repair. The durability and long-term outcomes of this technique in a larger cohort remain to be elucidated.

Impact of head and neck radiation on long-term outcomes after carotid revascularization

OBJECTIVE

Radiation-induced carotid artery stenosis (RICS) is a well-described phenomenon seen after head and neck cancer radiation. Previously published literature suggests that, compared with atherosclerotic disease, RICS may result in worse long-term outcomes and early restenosis. This study aims to evaluate the effect of radiation on long-term outcomes after various carotid revascularization techniques using a multi-center registry database.

METHODS

Patients in the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) registry for carotid artery intervention (carotid endarterectomy [CEA]; transfemoral carotid artery stenting [CAS]; transcarotid artery revascularization [TCAR]), who are 65 years or older were included in the study. VQI Vascular Implant Surveillance and Interventional Outcomes Network (VISION) Medicare-linked database was used to obtain long-term procedure-specific outcomes. Primary endpoints were 3-year death, stroke, and reintervention. We performed propensity matching between patients with prior radiation and those without. Kaplan-Meier analysis and a multivariate logistic regression model were used to analyze the outcome variables.

RESULTS

A total of 56,472 patients had undergone carotid revascularization (CEA, n = 48,307; TCAR, n = 4593; CAS, n = 3572), 1244 patients with prior radiation and 54,925 patients without prior radiation. The prior radiation group was more likely to be male (71.9% vs 60.3%; P < .01), to receive a stent (47.5% vs 13.5%; P < .01), and to be on P2Y12 inhibitor (55.2% vs 38.3%; P < .01). Propensity matching was performed on 1223 patients (CEA, n = 655; TCAR, n = 292; CAS, n = 287). There were no significant differences in 30-day outcomes for death, stroke, or major adverse cardiovascular events for all three procedures. The prior radiation group had higher rates of cranial nerve injury (3.7% vs 1.8%; P = .04) and 90-day readmission (23.5% vs 18.3%; P = .01) after CEA. For long-term outcomes, prior radiation significantly increased mortality risk for CEA and CAS (hazard ratio [HR], 1.77; 95% confidence interval [CI], 1.38-2.27 and HR, 1.56; 95% CI, 1.02-2.36, respectively). The 3-year risk of stroke for CEA in radiated patients was also significantly higher (HR, 1.47; 95% CI, 1.03-2.09) compared with non-radiated patients. Prior radiation did not significantly affect death and stroke in patients undergoing TCAR. Prior radiation also did not impact the rates of short and long-term reintervention after CEA, CAS, or TCAR.

CONCLUSIONS

Prior head and neck radiation significantly increases the risk for mortality and stroke for CEA and the risk for mortality after CAS. Long-term outcomes for TCAR are not significantly affected by prior radiation. TCAR may be the preferred treatment modality for patients with radiation-induced carotid stenosis.

Digital coincidence counting with 4πβ(PPC)-γ for the standardization of 60Co

A 4πβ(PPC)-γ coincidence system has been made at KRISS based on a digital DAQ. 60Co sources were measured to verify the system. The maximum detection efficiency for beta particles was estimated to be 96.7 %. Massic activities for sample sources had 0.005 % of the sample variability error, which was well within the expanded standard uncertainty of 0.54 % (k = 2).

A simplified cranial cavity model to understand the relationship between intracranial pressure and dural sinus pressure

Although accurate intracranial pressure (ICP) monitoring is essential for the diagnosis and treatment of severe brain diseases, current methods are performed invasively. Therefore, a safe and less invasive ICP measurement is required. The purpose of our study was to develop a simplified cranial cavity model for a better understanding of the relationship between the ICP and the pressure measurement within the dural venous sinus (DVS) to support the validity of using sinus pressure as the surrogate of the ICP. The in-house cranial cavity model had three components: the brain part, the DVS part, and the subarachnoid space (SAS) part. Pressure in other parts was measured when the pressure in the SAS part and, separately, brain part was increased from 0 (baseline) to 50 mmHg at intervals of 10 mmHg. When the pressure in the SAS part was increased from 10 to 50 mmHg at 10 mmHg interval, pressures of both the brain and DVS parts increased without significant difference (all P > 0.05). However, pressures in both the SAS and DVS parts differed while the pressure in the brain part was increased. The pressures in both parts showed about 70% of the increase in the brain part. Nevertheless, the pressures in the SAS and DVS parts were not significantly different (P > 0.05). A simplified in-house cranial cavity model was developed consisting of three compartments to represent the actual intracranial spaces. The pressure measurement within the DVS was feasible to use as a surrogate for the ICP measurement.

Superior mesenteric artery aneurysm endovascular repair

Superior mesenteric artery aneurysms are rare and associated with high mortality rates in cases of rupture. Current Society for Vascular Surgery guidelines recommend treatment of all superior mesenteric artery aneurysms regardless of size. A 53-year-old woman who was admitted for abdominal pain was found with a 14-cm, ruptured superior mesenteric artery branch aneurysm. Endovascular approach was performed with microvascular plug embolization of a feeding branch and aneurysm sac exclusion with a stent graft. Four months later, the patient demonstrated a 21% regression of the aneurysm and stent patency. Thus, timely diagnosis and treatment of superior mesenteric artery aneurysms with endovascular techniques can reduce potential complications.

Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at sqrt[s]=510 GeV in p[over →]+p[over →] Collisions

We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510  GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510  GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02<x<0.08, with direct sensitivity to the sign of the gluon contribution.

Early Results and Feasibility of Total Endovascular Aortic Arch Repair Using 3-Vessel Company-Manufactured and Physician-Modified Stent-Grafts

OBJECTIVE

Total endovascular repair of aortic arch aneurysms is feasible in select patients. This study aims to evaluate the feasibility and early outcomes of total endovascular arch repair using 3-vessel company-manufactured devices (CMDs) and physician-modified endo grafts (PMEGs).

METHODS

Patients unfit for open repair who underwent 3-vessel total arch repair at a single institution from 2018 to 2021 were reviewed. Patients received either 3-vessel inner-branch CMDs or PMEGs. Three-vessel designs were used to incorporate the innominate, left common carotid, and left subclavian arteries. The antegrade inner branches in both devices were accessed via right brachial or carotid approach. The left carotid was accessed via carotid cutdown or femoral approach. The left subclavian artery was accessed via transfemoral approach. The study endpoints included procedural technical success, patient survival, neurologic events, cardiac complications, reinterventions, and target artery patency.

RESULTS

Nine patients underwent treatment. Four patients were treated with PMEGs, and 5 with CMDs. Procedural technical success was 100%. There were no in-hospital deaths. There were no strokes, transient ischemic attacks, myocardial infarction, or spinal ischemia in the perioperative period. Major adverse events occurred in 3 patients (33%). Two (22%) vascular access complications and one (11%) acute kidney injury occurred. One (11%) patient required early reintervention for an access complication. The median follow-up period was 358 days (CMD, 392 days; PMEG, 198 days). There was a late reintervention and conversion to open repair at 142 days of follow-up in a patient with a PMEG that developed an aortic infection, leading to death on postoperative day 239. The mean length of stay was 7±4 days. Computed tomography imaging obtained during the immediate postoperative period revealed endoleak in 6 (66%) patients, out of which 5 resolved spontaneously and 1 required reintervention via left subclavian artery stenting. Target artery patency was 100% at the end of the follow-up period.

CONCLUSIONS

Three-vessel total endovascular aortic arch repair using a CMD or PMEG is feasible with optimal early outcomes. Physician-modified stent-grafts are a feasible option for patients who do not meet anatomic criteria for CMDs.

CLINICAL IMPACT

Management of aortic arch disease remains a significant challenge in vascular surgery. This study showcases the feasibility and safety of using a total endovascular approach to repair the aortic arch, which could potentially reduce morbidity and mortality associated with traditional surgical approaches. The results suggest that this minimally invasive technique could be an alternative treatment option for high-risk patients and could significantly improve outcomes for those requiring aortic arch repair. Overall, this study represents a promising development in the field of endovascular surgery and highlights the potential to improve patient outcomes.

Endovascular repair of traumatic axillary artery transection associated with scapulothoracic dissociation complicated by stent separation

We report the case of a 23-year-old female pedestrian who had been struck by a car and had presented with axillary artery transection in the setting of scapulothoracic dissociation. The initial endovascular repair was compromised by her shoulder instability and had required the addition of bridging stent placement. Caution is advised with endovascular repair in this clinical scenario because of possible stent separation.

Endovascular Reconstruction Aortic Bifurcation for Aortic Pseudoaneurysm in a Pediatric Trauma Patient

Endovascular treatment options for vascular injury in pediatric patients are quite limited owing to concerns regarding long-term durability and the lack of devices suitable for the pediatric anatomy. However, in rare circumstances, open surgical therapy will not be an option, and patients will require unconventional endovascular solutions for lifesaving or limb-saving therapies. In the present report, we describe an endovascular treatment of a pediatric patient for whom initial surgical management of a blunt abdominal aortic injury had failed, with subsequent development of an aortic pseudoaneurysm. A 10-year-old girl had presented after a high-speed motor vehicle accident with a seatbelt sign. Multiple abdominal injuries were identified, including blunt aortic injury, significant devitalization of the small bowel, colonic perforation with fecal contamination, multiple lumbar spine fractures, and pulmonary contusions. The patient developed bilateral lower extremity ischemia from the aortic injury and had initially undergone open repair. One month later, the patient had developed a pseudoaneurysm of the aorta near the aortic bifurcation. Because of the hostile abdomen and ensuing short gut syndrome, the pseudoaneurysm was managed using endovascular techniques. The limb of an Excluder internal iliac branch endoprosthesis (W.L. Gore & Associates, Flagstaff, AZ) was used as the endograft. The aortic bifurcation was raised and reconstructed using four Viabahn self-expanding stents (W.L. Gore & Associates). The completion angiogram showed complete resolution of the pseudoaneurysm. The follow-up computed tomography angiogram showed widely patent stent grafts with complete resolution of the pseudoaneurysm. Endovascular management of traumatic vascular injuries in pediatric patients is feasible. The likelihood of reintervention in the future is high with patient growth. However, it is a viable option in lifesaving or limb-saving situations in which open repair is high risk.

Three-dimensional navigation-guided percutaneous trans-symphyseal screw for mechanically unstable pubic symphysis diastasis

Minimally invasive trans-symphyseal screw (TSS) for pubic symphysis diastasis was recently advocated, and its feasibility and reproducibility under 3D-navigation guidance are explored. Fifteen cases between 2016 and 2021 with a background of pubic symphysis diastasis are reviewed in this case series. Twenty-two TSS were inserted with an average Injury Severity Score of 35.3. Sixty percent received a one-stage procedure including fracture reduction, intra-operative 3D imaging, and planning followed by execution. The mean operative time and blood loss were 132 minutes and 160 ml, respectively. Average fracture healing was 5.8 months with two delayed unions at 9 months. The pubic symphysis distance was maintained in all cases at 6 months post-op. The average Marjeed score, Multicenter Study Group Pelvic Outcome Score, and Numeric pain rating scale were 60.2, 6.5, and 2.7, respectively. We conclude that 3D-navigation-guided percutaneous TSS restores pelvic stability and provides satisfactory pain control, and thus a safe and effective alternative to open reduction internal fixation.

Standardization of 129I using the movable 4πβ(LS)-X(NaI(Tl)) system

The ¹²⁹I standardization, using the movable 4πβ(LS)-X(NaI(Tl)) coincidence system, was performed for two ¹²⁹I radioactive sources - one was dissolved in 0.1M NaOH solution and the other in 0.1M HNO₃ solution. The system incorporates three movable PM tubes for a β-counter placed on a plane and a X-ray detector that can be moved up to the bottom of the vial. The β-efficiency depending on the amount of radioactive solution was investigated with 14 liquid scintillation samples prepared by gravimetrically dispensing 4.4-145 mg of ¹²⁹I radioactive solution. The β-efficiencies above 90% were observed at less than 56 mg, but it was at most 70% at 145 mg. This occurred regardless of the activity of the sample or the type of chemical solution used to dissolve ¹²⁹I source. The activity concentration of each ¹²⁹I source was determined by efficiency-extrapolation method for samples with an activity range of 0.28-4.5 kBq. The β-efficiency points were derived over 10 intervals by moving 3-PM tubes in fine steps of about 1 mm from the sample. The highest value for β-efficiency was 95%. The combined uncertainty were 0.25% and 0.26%, respectively. The stated precision obtained using the system is better than that previously reported in the literature obtained by the triple to double coincidence ratio (TDCR) or the CIEMAT/NIST efficiency tracing method.

Photocurable bioresorbable adhesives as functional interfaces between flexible bioelectronic devices and soft biological tissues

Flexible electronic/optoelectronic systems that can intimately integrate onto the surfaces of vital organ systems have the potential to offer revolutionary diagnostic and therapeutic capabilities relevant to a wide spectrum of diseases and disorders. The critical interfaces between such technologies and living tissues must provide soft mechanical coupling and efficient optical/electrical/chemical exchange. Here, we introduce a functional adhesive bioelectronic-tissue interface material, in the forms of mechanically compliant, electrically conductive, and optically transparent encapsulating coatings, interfacial layers or supporting matrices. These materials strongly bond both to the surfaces of the devices and to those of different internal organs, with stable adhesion for several days to months, in chemistries that can be tailored to bioresorb at controlled rates. Experimental demonstrations in live animal models include device applications that range from battery-free optoelectronic systems for deep-brain optogenetics and subdermal phototherapy to wireless millimetre-scale pacemakers and flexible multielectrode epicardial arrays. These advances have immediate applicability across nearly all types of bioelectronic/optoelectronic system currently used in animal model studies, and they also have the potential for future treatment of life-threatening diseases and disorders in humans.

Fully implantable and bioresorbable cardiac pacemakers without leads or batteries

Temporary cardiac pacemakers used in periods of need during surgical recovery involve percutaneous leads and externalized hardware that carry risks of infection, constrain patient mobility and may damage the heart during lead removal. Here we report a leadless, battery-free, fully implantable cardiac pacemaker for postoperative control of cardiac rate and rhythm that undergoes complete dissolution and clearance by natural biological processes after a defined operating timeframe. We show that these devices provide effective pacing of hearts of various sizes in mouse, rat, rabbit, canine and human cardiac models, with tailored geometries and operation timescales, powered by wireless energy transfer. This approach overcomes key disadvantages of traditional temporary pacing devices and may serve as the basis for the next generation of postoperative temporary pacing technology.

Intraoperative surgical strategy changes in patients with chronic and end-stage renal disease undergoing coronary artery bypass grafting

OBJECTIVES

Factors such as more diffuse atherosclerosis, plaque instability and accelerated vascular calcification in patients with chronic and end-stage renal disease (ESRD) can potentially present intraoperative challenges in coronary artery bypass grafting (CABG) procedures. We evaluated whether patients with chronic and ESRD experienced more surgical strategy changes and/or graft revisions than patients with normal renal function when undergoing CABG procedures according to a protocol for intraoperative high-frequency ultrasound and transit-time flow measurement (TTFM).

METHODS

Outcomes of CABG for patients with chronic and ESRD and patients with normal renal function enrolled in the multicentre prospective REQUEST (REgistry for QUality assESsmenT with Ultrasound Imaging and TTFM in Cardiac Bypass Surgery) study were compared retrospectively. The primary end point was frequency of intraoperative surgical strategy changes. The secondary end point was post-protamine TTFM parameters.

RESULTS

There were 95 patients with chronic and ESRD and 921 patients with normal renal function. Patients with chronic and ESRD undergoing CABG according to a protocol for intraoperative high-frequency ultrasound and TTFM had a higher rate of strategy changes overall [33.7% vs 24.3%; odds ratio (OR) = 1.58; 95% confidence interval (CI) = 1.01-2.48; P = 0.047] and greater revisions per graft (7.0% vs 3.4%; odds ratio = 2.14; 95% CI = 1.17-3.71; P = 0.008) compared to patients with normal renal function. Final post-protamine graft TTFM parameters were comparable between cohorts.

CONCLUSIONS

Patients with chronic and ESRD undergoing CABG procedures with high-frequency ultrasound and TTFM experience more surgical strategy changes than patients with normal renal function while achieving comparable graft flow.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT02385344.

Development of a movable 4πβ(LS)-γ coincidence counting system for activity standardization of β-γ emitters

A new movable 3PM-γ coincidence system, based on 4πβ(LS)-γ coincidence counting, for activity measurement of β-γ emitters has been designed at the Korea Research Institute of Standards and Science (KRISS). The system incorporates 3 PM tubes on the plane and two detectors placed above and below the center of the plane. The 3 PM tubes for β-counters in the plane are movable up to 100 mm from a liquid scintillation vial, thus enabling the variation of β-detection efficiencies by a geometrical technique. A NaI(Tl) γ-counter was set above for the present work. The β-event is determined by counting the logical sum of three double coincidences. All the necessary electronics, i.e., logical sum, adjusting the duration of dead-time of each counting channel and coincidence resolving times, and analyzing coincidence relation, were specially designed to be fabricated in an integrated circuit. Details of the detectors, the electronics, the overall movable 3PM-γ coincidence system are presented, as well as the results of investigations to assess its operating characteristics. Validation measurements have been performed with ⁶⁰Co and ⁵⁷Co sources. The highest β-detection efficiency achieved with ⁶⁰Co and ⁵⁷Co was 97% and 95%, respectively. The activity concentration determined with a new system agreed with calibrated values within the uncertainty range. Further results from validation measurements and the corresponding uncertainty budgets are presented.

Fenestrated Endovascular Aneurysm Repair Affords Fewer Renal Complications than Open Surgical Repair for Juxtarenal Abdominal Aortic Aneurysms in Patients with Chronic Renal Insufficiency

OBJECTIVE

Although fenestrated endovascular aneurysm repair (FEVAR) has been associated with lower morbidity and mortality than open surgical repair (OSR) in juxtarenal aneurysms (JAAA), there is a paucity of data in the literature comparing outcomes of the approaches specifically in patients with chronic renal insufficiency (CRI). We hypothesized that benefits of FEVAR over OSR observed in the general patient population may be diminished in CRI patients due to their heightened vulnerability to renal dysfunction stemming from contrast-induced nephropathy. This study compares 30-day outcomes between FEVAR and OSR for JAAA in patients with non-dialysis dependent CRI.

METHODS

All adults with estimated glomerular filtration rate (eGFR) < 60 mL/min (but not requiring dialysis) undergoing elective, non-ruptured JAAA repairs were identified in the American College of Surgeons - National Surgical Quality Improvement (ACS-NSQIP) Targeted EVAR and AAA databases from 2012-2018. JAAA were identified by recorded proximal aneurysm extent. FEVAR patients were identified in the Targeted EVAR database as those receiving the "Cook Zenith Fenestrated" endograft. OSR cases were defined as those that required proximal clamp positions "above one renal" or "between SMA & renals." Infra-renal or supra-celiac proximal clamp placement, or cases involving concomitant renal/visceral revascularization were excluded. Thirty-day outcomes including mortality, major adverse cardiovascular events (MACE), pulmonary, and renal complications were compared between FEVAR and OSR groups.

RESULTS

There were 284 patients with CRI who underwent elective repair of JAAA (FEVAR: 89; OSR: 195). FEVAR patients were significantly older than those undergoing OSR (77.3±7.2 vs. 74.2±7.7, P=0.001) and less likely to be smokers (25.8% vs 42.1%; P = 0.009). Other baseline demographic and pre-operative parameters were comparable between the two groups.Multivariable analysis revealed no significant difference between FEVAR and OSR in 30-day mortality (4.5% vs 4.6%; OR=1.22; 95% CI=0.35 - 4.22; P=0.753) or unplanned re-operation (4.5% vs 5.1%; OR=0.78; 95% CI=0.22 - 2.70; P=0.693). Patients undergoing FEVAR had significantly fewer pulmonary complications (3.4% vs 18.5%; OR=0.12; 95% CI=0.03 - 0.42; P<0.001) and renal dysfunction (3.4% vs 11.8%; OR 0.24 95% CI=0.07 - 0.86; P=0.029) compared to OSR. FEVAR was also associated with significantly shorter ICU and hospital lengths of stay (ICU stay: 0 days vs 3 days, P<0.0001; hospital stay: 3 days vs 8 days, P<0.0001).

CONCLUSION

For patients with chronic renal insufficiency, FEVAR offered improved perioperative renal morbidity compared to OSR without a corresponding mortality benefit. Future studies will be required to determine long term outcomes of this procedure in this vulnerable population.

Outcomes of Paraesophageal Hernia Repair: Analysis of the Veterans Affairs Surgical Quality Improvement Program Database

BACKGROUND

While there have been many outcome studies on paraesophageal hernia repair in the civilian population, there is sparse recent data on the veteran population. This study analyzes the mortality and morbidities of veterans who underwent paraesophageal hernia repair in the Veterans Affairs Surgical Quality Improvement Program database.

METHODS

Veterans who underwent paraesophageal hernia repair from 2010 to 2017 were identified using Current Procedural Terminology codes. Multivariable analysis was used to compare laparoscopic and open, including abdominal and thoracic approaches, groups. The outcomes were postoperative complications and mortality.

RESULTS

There were 1607 patients in the laparoscopic group and 366 in the open group, with 84.1% men and mean age of 61 years. Gender and body mass index did not influence the type of surgical approach. The mortality rates at 30 and 180 days were 0.5% and 0.7%, respectively. Postoperative complications, including reintubation (2.2%), pneumonia (2.0%), intubation > 48 h (2.0%), and sepsis (2.0%) were higher in the open group (15.9% versus 7.2%, p < 0.001). The laparoscopic group had a significantly shorter length of stay (4.3 versus 9.6 days, p < 0.001) and a lower percentage of return to surgery within 30 days (3.9% versus 8.2%, p < 0.001) than the open group. The ratio of open versus laparoscopic paraesophageal hernia repairs varied significantly by different Veterans Integrated Services Network regions.

CONCLUSIONS

Veterans undergoing laparoscopic paraesophageal hernia repair experience similar outcomes as patients in the private sector. Veterans who underwent laparoscopic paraesophageal hernia repair had significantly less complications compared to an open approach even after adjusting for patient comorbidities and demographics. The difference in open versus laparoscopic practices between various regions requires further investigation.

Outcomes of open and endovascular interventions in patients with chronic limb threatening ischemia

OBJECTIVES

Widespread adoption of endovascular therapy for the treatment of chronic limb-threatening ischemia has transformed the field of vascular surgery. In this modern era, we aimed to define where open surgical interventions are of greatest benefit for limb salvage.

METHODS

Patients who underwent interventions for chronic limb-threatening ischemia were identified in the vascular-targeted lower extremity National Surgical Quality Improvement Program database for open surgical interventions (OPEN) and endovascular surgical interventions (ENDO) from 2011 to 2017. Patients were further stratified based on the criteria of chronic limb-threatening ischemia (rest pain or tissue loss), and the location of the diseased arteries (femoropopliteal or tibioperoneal). The main outcomes measured included 30-day mortality, amputation, and major adverse cardiovascular events.

RESULTS

A total of 17,193 patients were revascularized for chronic limb-threatening ischemia: 10,532 were OPEN and 6661 were ENDO. OPEN had higher 30-day mortality, major adverse cardiovascular events, pulmonary, renal dysfunction, and wound complications. However, OPEN resulted in significantly lower 30-day major amputation (3.8% vs. 5.0%, odds ratio (OR): 0.83 [0.72-0.97], P = .018). Subgroup analysis revealed a higher mortality rate in OPEN was observed only in tibioperoneal intervention for tissue loss. Major adverse cardiovascular event was higher in OPEN for most subgroups. OPEN for patients with tissue loss had significantly lower amputation rate than ENDO in both femoropopliteal and tibioperoneal subgroups (3.7% vs. 5.1%, OR: 0.76 [0.59-0.98], P = .036, and 4.7% vs. 6.6%, OR: 0.74 [0.57-0.96], P = .024, respectively). The benefit of open surgery in reducing the amputation rate was not seen in patients with rest pain.

CONCLUSIONS

Open surgical intervention is associated with significantly better limb salvage than endovascular intervention in patients with tissue loss. Surgical options should be given more emphasis as the first-line option in this cohort of patients unless the cardiopulmonary risk is prohibitive.

Open surgical repair of juxtarenal abdominal aortic aneurysms in the elderly is not associated with increased thirty-day mortality compared with fenestrated endovascular grafting

OBJECTIVE

Endovascular repair of juxtarenal abdominal aortic aneurysms (JAAAs) with fenestrated grafts (fenestrated endovascular aneurysm repair [FEVAR]) has been reported to decrease operative mortality and morbidity compared with open surgical repair (OSR). However, previous comparisons of OSR and FEVAR have not necessarily included patients with comparable clinical profiles and aneurysm extent. Although FEVAR has often been chosen as the first-line therapy for high-risk patients such as the elderly, many patients will not have anatomy favorable for FEVAR. At present, a paucity of data has examined the operative outcomes of OSR in elderly patients for JAAAs relative to FEVAR. Therefore, we chose to perform a propensity-matched comparison of OSR and FEVAR for JAAA repair in patients aged ≥70 years.

METHODS

Patients aged ≥70 years who had undergone elective nonruptured JAAA repairs from 2012 to 2018 were identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) targeted endovascular aneurysm repair (EVAR) and AAA databases. Patients who had undergone FEVAR were identified in the targeted EVAR database as those who had received the Cook Zenith Fenestrated endograft (Cook Medical, Bloomington, Ind). Because our study specifically examined JAAAs, those patients who had undergone OSR with supraceliac proximal clamping or concomitant renal/visceral revascularization were excluded. A 1:1 propensity-match algorithm matched the OSR and FEVAR patients by preoperative clinical and demographic characteristics, operative indications, and aneurysm extent. The 30-day outcomes, including mortality, major adverse cardiovascular events, and pulmonary and renal complications, were compared between the propensity-matched OSR and FEVAR groups.

RESULTS

A 1:1 propensity match was achieved, and the final analysis included 136 OSR patients and 136 FEVAR patients. No significant differences were found in 30-day mortality (4.4% vs 3.7%; odds ratio [OR], 1.21; 95% confidence interval [CI], 0.36-4.06; P = .759) between the OSR and FEVAR groups. OSR was associated with a higher incidence of major adverse cardiovascular events compared with FEVAR; however, the trend was not statistically significant (8.1% vs 3.7%; OR, 2.31; 95% CI, 0.78-6.82; P = .131). Compared with FEVAR, the OSR group had significantly greater rates of pulmonary complications (19.1% vs 3.7%; OR, 6.19; 95% CI, 2.30-16.67; P < .001) and renal complications (8.1% vs 2.2%; OR, 3.90; 95% CI, 1.06-14.31; P = .040).

CONCLUSIONS

In the samples assessed in the present study, the results with OSR of JAAAs in the elderly did not differ from those of FEVAR with respect to 30-day mortality despite a greater incidence of pulmonary and renal complications. Although FEVAR should remain the first-line therapy for JAAAs in elderly patients, OSR might be an acceptable alternative for select patients with anatomy unfavorable for FEVAR.

Thirty-day outcomes of open abdominal aortic aneurysm repair by proximal clamp level in patients with normal and impaired renal function

OBJECTIVE

Open surgical repair (OSR) of abdominal aortic aneurysms (AAAs) has often been reserved in contemporary practice for complex aneurysms requiring a suprarenal or supraceliac proximal clamp level. The present study investigated the associated 30-day outcomes of different proximal clamp levels in OSR of complex infrarenal/juxtarenal AAA in patients with normal renal function and those with chronic renal insufficiency (CRI).

METHODS

All patients undergoing elective OSR of infrarenal and juxtarenal AAA were identified in the American College of Surgeons National Surgical Quality Improvement Program-targeted AAA database from 2012 to 2018. The patients were stratified into two cohorts (normal renal function [estimated glomerular filtration rate, ≥60 mL/min] and CRI [estimated glomerular filtration rate, <60 mL/min and no dialysis]) before further substratification into groups by the proximal clamp level (infrarenal, inter-renal, suprarenal, and supraceliac). The 30-day outcomes, including mortality, renal and pulmonary complications, and major adverse cardiovascular event rates, were compared within each renal function cohort between proximal clamp level groups using the infrarenal clamp group as the reference. Supraceliac clamping was also compared with suprarenal clamping.

RESULTS

A total of 1284 patients with normal renal function and 524 with CRI were included in the present study. The proximal clamp levels for the 1808 patients were infrarenal for 1080 (59.7%), inter-renal for 337 (18.6%), suprarenal for 279 (15.4%), and supraceliac for 112 (6.2%). In the normal renal function cohort, no difference was found in 30-day mortality with any clamp level. Increased 30-day acute renal failure was only observed in the supraceliac vs infrarenal clamp level comparison (5.9% vs 1.5%; adjusted odds ratio [aOR], 3.97; 95% confidence interval [CI], 1.04-5.18; P = .044). In the CRI cohort, supraceliac clamping was associated with an increased rate of renal composite complications (22.7% vs 5.6%; aOR, 8.81; 95% CI, 3.17-24.46; P < .001) and ischemic colitis (13.6% vs 3.0%; aOR, 4.78; 95% CI, 1.38-16.62; P = .014) compared with infrarenal clamping and greater 30-day mortality (13.6% vs 2.4%; aOR, 6.00; 95% CI, 1.14-31.55; P = .034) and renal composite complications (22.7% vs 10.8%; aOR, 2.87; 95% CI, 1.02-8.13; P = .047) compared with suprarenal clamping. Suprarenal clamping was associated with greater renal dysfunction (10.8% vs 5.6%; aOR, 2.77; 95% CI, 1.08-7.13; P = .035) compared with infrarenal clamping, with no differences in mortality. No differences were found in 30-day mortality or morbidity for inter-renal clamping compared with infrarenal clamping in either cohort. No differences were found in major adverse cardiovascular events with higher clamp levels in either cohort.

CONCLUSIONS

In elective OSR of infrarenal and juxtarenal AAAs for patients with CRI, this study found a heightened mortality risk with supraceliac clamping and increased renal morbidity with suprarenal clamping, though these effects were not present for patients with normal renal function. Every effort should be made to keep the proximal clamp level as low as possible, especially in patients with CRI.

Failed Prior Endovascular Interventions Do Not Affect 30-day Cardiovascular or Limb-related Outcomes of Infrainguinal Bypasses for Chronic Limb Threatening Ischemia

BACKGROUND

It is often hypothesized that failed prior endovascular intervention could adversely affect the outcome of subsequent infrainguinal bypass in the corresponding limb. However, this perception is not well supported in the literature because of conflicting data. The aim of this study is to address this controversial issue via analysis of a multicenter prospectively collected database.

METHODS

Patients who underwent infrainguinal bypass for chronic limb threatening ischemia (CLTI) were identified in the targeted American College of Surgeons National Surgical Quality Improvement Program database from 2011 to 2017. These patients were stratified into 4 groups: first time femoral-popliteal bypass, femoral-popliteal bypass after failed prior endovascular revascularization, first time femoral-tibial bypass, and femoral-tibial bypass after failed prior endovascular revascularization. Thirty-day outcomes including mortality, graft patency, major amputations, and major organ dysfunction were measured.

RESULTS

We identified 7,044 patients who underwent surgical bypasses for CLTI. Patients were mostly well matched among the 4 groups except for differences in sex, hypertension, and preoperative renal function. In terms of major adverse cardiovascular events and major adverse limb events, femoral-popliteal or femoral-tibial bypasses after failed prior endovascular intervention had comparable 30-day outcomes to first-time bypasses. However, patients with failed prior endovascular intervention had increased rates of postoperative wound infection, required significantly more blood transfusions, and had longer operative time.

CONCLUSIONS

Failed prior endovascular intervention does not adversely affect 30-day outcomes of subsequent infrainguinal bypass surgery in mortality, limb salvage, or other major cardiovascular complications.

Erratum: Evolution of π^{0} Suppression in Au+Au Collisions from sqrt[s_{NN}]=39 to 200 GeV [Phys. Rev. Lett. 109, 152301 (2012)]

This corrects the article DOI: 10.1103/PhysRevLett.109.152301.

Long-term Outcomes of Coronary Artery Bypass Grafting in Veterans with Left Main Coronary Artery Disease

BACKGROUND

Studies of the civilian population with left main coronary artery disease (LMCAD) who underwent coronary artery bypass grafting (CABG) have shown 2% to 4.2% 30-day mortality. However, there is a lack of reporting from the veteran population. Here we analyze the outcomes of veterans with LMCAD who underwent CABG by a single surgeon at a single Veterans Affairs Medical Center (VAMC).

METHODS

Veterans who underwent isolated CABG between 1998 to 2018 at a VAMC were further divided into a group with significant left main coronary artery disease (LMCAD) of stenosis greater than or equal to 50% and a group without left main coronary artery stenosis (non-LMCAD). The primary outcome was mortality. Secondary outcomes included postoperative complications. Multivariable regression analysis and Kaplan-Meier survival analysis were used to compare the two cohorts.

RESULTS

The demographics and comorbidities are similar between the two cohorts except for higher average age and percentage of stroke in the LMCAD group (n = 509) compared to non-LMCAD (n = 927). Perioperative complications are comparable between the two groups except for increased length of stay (LOS) in the LMCAD group (12.9 ± 15.9 days versus 10.9 ± 9.0 days in non-LMCAD, P < .001). 30-day mortality in the LMCAD group is 4.1% versus 1.4% in non-LMCAD. However, Kaplan-Meier curves show no significant difference in adjusted overall survival throughout 15 years between the groups (P = .560).

CONCLUSION

Veterans with LMCAD who underwent CABG have similar postoperative complications compared to non-LMCAD group. The 30-day mortality is higher in the LMCAD group; however, there is no difference in long-term survival.

The primary system for measurement of beta emitting radioactive gases at KRISS

Korea Research Institute of Standards and Science (KRISS) is developing a length-compensated proportional counting (LCPC) system as a primary system for standardization of beta emitting radioactive gases. The pilot experiment was performed with ⁸⁵Kr and the optimized high voltage and pressure were found to be 1700 V and 0.203 MPa, respectively. The total activity of ⁸⁵Kr was deduced by the length compensation of each count. The expanded uncertainty was estimated to be around 0.8% (k = 2) for the ⁸⁵Kr measurement.

Design of optimal digital filter and digital signal processing for a CdZnTe high resolution gamma-ray system

We have developed an online digital signal processing system based on an FPGA. The system consists of pile-up rejection, baseline restorer, peak detection and pole-zero cancellation for evaluation of deposited energy in the detector. The shaping algorithm employed is a Moving Window Deconvolution (MWD) to shape digitized data into a trapezoidal form. For the purpose of verification, the developed digital system was tested for ¹³⁷Cs gamma rays. The entire system is programmed using the LabVIEW environment.

Long-Term Outcomes of Coronary Artery Bypass Grafting in Veterans with Ischemic Cardiomyopathy

BACKGROUND

The Surgical Treatment for Ischemic Heart Failure (STICH) trial showed that surgical revascularization in ischemic cardiomyopathy (ICM) patients improves long-term mortality compared with medical treatment alone. This study examines how veterans with ICM undergoing revascularization fare against patients without ICM; it also examines the outcomes in the veteran population.

METHODS

This is a retrospective review of a single-center database. From 2000 to 2018, 1,461 patients underwent isolated coronary artery bypass grafting (CABG). Two-hundred-one patients with an ejection fraction less than 35% were classified as the ICM cohort. The primary outcome was mortality. Secondary outcomes included postoperative complications. Subgroup analysis was performed within the ICM cohort comparing off-pump CABG (OPCAB) versus on-pump CABG (ONCAB).

RESULTS

ICM patients had a higher incidence of myocardial infarction (MI), diabetes, chronic kidney disease (CKD), and preoperative intra-aortic balloon pump (IABP) use. The non-ICM cohort was more functionally independent. OPCAB was performed in 80.1% of ICM and 66.3% of non-ICM cohorts. There was no statistical difference between ICM and non-ICM cohorts in 30-day mortality (OR 1.94[0.79 - 4.75], P = .15). The ICM cohort had an increased 5-year mortality (OR 1.75[1.14 - 2.69], P = .01) and 10-year mortality (OR 1.71[1.09 - 2.67], P = .02). The ICM cohort showed improved, although not statistically significant, short-term mortality with OPCAB compared with ONCAB (3.1% versus 12.5%, OR 0.31[0.05 - 1.82], P = .20).

CONCLUSION

Veterans with ICM undergoing CABG demonstrated similar short-term survival compared with non-ICM veterans. The long-term survival in the ICM cohort still is inferior to patients without ICM. There is a trend toward improved short-term survival in patients with ICM undergoing OPCAB.

Association between time to treatment and functional outcomes according to the Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score in endovascular stroke therapy

BACKGROUND AND PURPOSE

The rate at which the chance of a good outcome of endovascular stroke therapy (EVT) decays with time when eligible patients are selected by baseline diffusion-weighted magnetic resonance imaging (DWI-MRI) and whether ischaemic core size affects this rate remain to be investigated.

METHODS

This study analyses a prospective multicentre registry of stroke patients treated with EVT based on pretreatment DWI-MRI that was categorized into three groups: small [Diffusion-Weighted Imaging Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS)] (8-10), moderate (5-7) and large (<5) cores. The main outcome was a good outcome at 90 days (modified Rankin Scale 0-2). The interaction between onset-to-groin puncture time (OTP) and DWI-ASPECTS categories regarding functional outcomes was investigated.

RESULTS

Ultimately, 985 patients (age 69 ± 11 years; male 55%) were analysed. Potential interaction effects between the DWI-ASPECTS categories and OTP on a good outcome at 90 days were observed (P_interaction  = 0.06). Every 60-min delay in OTP was associated with a 16% reduced likelihood of a good outcome at 90 days amongst patients with large cores, although no associations were observed amongst patients with small to moderate cores. Interestingly, the adjusted rates of a good outcome at 90 days steeply declined between 65 and 213 min of OTP and then remained smooth throughout 24 h of OTP (P_nonlinearity  = 0.15).

CONCLUSIONS

Our study showed that the probability of a good outcome after EVT nonlinearly decreased, with a steeper decline at earlier OTP than at later OTP. Discrepant effects of OTP on functional outcomes by baseline DWI-ASPECTS categories were observed. Thus, different strategies for EVT based on time and ischaemic core size are warranted.

Preservation of pelvic perfusion with iliac branch devices does not decrease ischemic colitis compared with hypogastric embolization in endovascular abdominal aortic aneurysm repair

OBJECTIVE

Ischemic colitis is a rare but devastating complication of endovascular repair of infrarenal abdominal aortic aneurysms. Although it is rare (0.9%) in standard endovascular aneurysm repair (EVAR), the incidence increases to 2% to 3% in EVAR with hypogastric artery embolization (HAE). This study investigated whether preservation of pelvic perfusion with iliac branch devices (IBDs) decreases the incidence of ischemic colitis.

METHODS

We used the targeted EVAR module in the American College of Surgeons National Surgical Quality Improvement Program database to identify patients undergoing EVAR of infrarenal abdominal aortic aneurysm from 2012 to 2017. The cohort was further stratified into average-risk and high-risk groups. Average-risk patients were those who underwent elective repair for sizes of the aneurysms, whereas high-risk patients were repaired emergently for indications other than asymptomatic aneurysms. Within these groups, we examined the 30-day outcomes of standard EVARs, EVAR with HAE, and EVAR with IBDs. The primary outcome was the incidence of ischemic colitis. Secondary outcomes included mortality, major organ dysfunction, thromboembolism, length of stay, and return to the operating room. The χ² test, Fisher exact test, Kruskal-Wallis test, and multivariate regression models were used for data analysis.

RESULTS

There were 11,137 patients who had infrarenal EVAR identified. We designated this the all-risk cohort, which included 9263 EVAR, 531 EVAR-HAE, and 1343 EVAR-IBD procedures. These were further stratified into 9016 cases with average-risk patients and 2121 cases with high-risk patients. In the average-risk group, 7482 had EVAR, 411 had EVAR-HAE, and 1123 had EVAR-IBD. In the high-risk group, 1781 had EVAR, 120 had EVAR-HAE, and 220 had EVAR-IBD. There was no significant difference in 30-day outcomes (including ischemic colitis) between EVAR, EVAR-HAE, and EVAR-IBD in the all-risk and high-risk groups. In the average-risk cohort, EVAR-HAE was associated with a higher mortality rate than EVAR (2.2% vs 1.0%; adjusted odds ratio, 2.58; P = .01). Although EVAR-IBD was not superior to EVAR-HAE in 30-day mortality, major organ dysfunction, or ischemic colitis in this average-risk cohort, EVAR-IBD exhibited a trend toward lower mortality compared with EVAR-HAE in this cohort, but it was not statistically significant (1.0% vs 2.2%; adjusted odds ratio, 0.42; P = .07).

CONCLUSIONS

Ischemic colitis is a rare complication of EVAR. HAE does not appear to increase the risk of ischemic colitis, and preservation of pelvic perfusion with IBDs does not decrease its incidence. Although HAE is associated with significantly higher mortality than standard EVAR in average-risk patients, the preservation of pelvic perfusion with IBDs does not appear to improve mortality over HAE.

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

A unified multidisciplinary fragility hip fracture pilot pathway in a trauma centre in Hong Kong: One-year outcome in the acute phase

Introduction:

The growing impact of fragility hip fracture (FHF) on the healthcare system and the society has become a major concern worldwide. A unified multidisciplinary FHF pathway from admission to rehabilitation and back to community was established in 2015. The acute phase of the pathway was put into pilot in our hospital to evaluate the outcome.

Method:

A designated FHF team was established in our centre since January 2015. The FHF pathway was piloted since June 2015. Patients admitted with a hip fracture resulting from fall on standing height were included. Major outcome parameters were compared in three phases: (1) before FHF team and FHF pathway (January to December 2014), (2) after FHF team but before FHF pathway (January to May 2015) and (3) after FHF team and FHF pathway (June 2015 to May 2016).

Result:

In phases 1, 2 and 3, 631, 263 and 634 patients were included, respectively. From phases 1 to 3, the average key performance indicator (KPI) has improved from 49.2% to 65.8% to 70.0% significantly; average acute length of stay (days) has improved from 13.7 to 13.4 to 11.3 significantly; total surgical complication rates have improved from 6.2% to 7.6% to 5.8%. The 30-day mortality rate and the unplanned readmission rate (within 28 days) have remained below 2.7% and 2.2%, respectively.

Conclusions:

Implementation of an FHF pathway can form a multidisciplinary platform that can improve the standard of care and outcome for our FHF patients in terms of KPI and also length of stay.

New knowledge added by this study:

A newly designed and implemented fragility hip fracture pathway in our centre as a pilot with the results evaluated.

Implications for clinical practice or policy:

With the increasing elderly population in Hong Kong and globally, there is a need to design and implement a fragility hip fracture (FHF) pathway to improve the care and effectiveness for FHF patients.

Abstract P3-03-31: Is sentinel lymph node biopsy necessary in all patients with early breast cancer?

Background and objectives : Since the results of the American College of Surgeons Oncology Group Z0011 published, the criteria for applying axillary lymph node (ALN) dissection was relaxed among early breast cancer patients who were scheduled for breast conserving surgery, adjuvant chemotherapy therapy, and adjuvant radiation therapy. SLNB criteria may be established if pathologic nodal status can be predicted. The aim of this study was to develop a nomogram for preoperative prediction of axillary node metastasis.

Methods: The records of 1650 patients with T1, T2 primary invasive breast cancer who were treated between January 2013 and September 2016 were selected from the medical database of Yonsei University (Seoul, South Korea). Those whom a preoperative diagnosis of axillary node metastases were excluded. Two nomogram that predicted three or more axillary metastasis and one or more axillary metastasis were developed using a binary logistic regression model with a training cohort. Internal validation was carried out adopting bootstrap method by validation cohort 500 times resampling.

Result: A total of 82 (4.8%) patients had three or more ALNs metastasis. Three hundred seventy five (17.4%) patients had one or more ALNs metastasis. Axillary metastasis was associated with Preoperative ALN suspicious image findings, clinical tumor size, Number of neoplastic foci, estrogen receptor status, Ki-67 expression, tumor marker. The nomogram was developed based on the clinical and statistically significant predictors. It had good discrimination performance (AUC 0.79, 95% CI, 0.73–0.85), (AUC 0.71, 95% CI, 0.67–0.74) and calibration fit.

Conclusion:Our nomogram might help predict the ALN metastasis in breast cancer patients. Patients with a low probability of ALN metastasis could be spared SLNB.

Citation Format: Yoon KH, Lee KB, Lee H, Lee J, Kim JY, Park HS, Park S, Kim SI, Cho YU, Park B-W. Is sentinel lymph node biopsy necessary in all patients with early breast cancer? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-31.

Abstract OT2-01-03: A prospective pilot study of simultaneous robotic assisted nipple sparing mastectomy and immediate reconstruction

Endoscopic breast surgery was expected to be an adequate technique to complete cancer clearance and preservation of the patient's body image. However, this technique has limitations including incomplete internal movements and unstable vision of a two dimensional camera due to inflexible endoscopic instruments especially during the skin flap formation. High resolution, ten-fold image magnification, and three-dimensional optics of robotic surgery help overcome the limitations of endoscopic surgery, and thus robotic surgery has been adopted in a wide range of intracorporeal procedures including breast surgery. However, few studies have evaluated feasibility and safety of robotic assisted nipple sparing mastectomy (RANSM) and immediate breast reconstruction (IBR) for the treatment of breast cancer. There were not any investigation to assess patients' satisfaction of cosmetic effect after performing RANSM and IBR. This study is aim to verify the feasibility and the safety of RANSM and IBR and to analyze cosmetic effect of the procedure and satisfaction of patients. The target number of enrollments is 15 patients. Patients who are diagnosed with early breast cancer or BRCA 1/2 mutation carriers are enrolled. Female patients over 20 years old who are candidates to preserve nipple areolar complex and considered to perform reconstruction with implants are prospectively collected. Written informed consents are mandatory. Patients who are considered the high possibility of postoperative radiation therapy according to preoperative stage are not included in this study. We exclude patients who want to undergo other methods of breast reconstruction than breast reconstruction with implants. Patients will undergo RANSM and IBR through a single axillary skin incision simultaneously. Regular follow-up at 1 month and 6 months after RANSM and IBR is scheduled to record recovery of a patient, amount of a drain, date of drain removal, and postoperative complications. Patient satisfaction questionnaire will be completed on the last follow-up day. To evaluate the safety of robotic assisted surgery, the oncologic safety (margin status of nipple areolar complex), postoperative recovery of a patient, and postoperative complications are investigated. We compare preoperative and postoperative 6 month photographs of patients and estimate the surgical outcome by objective indicators to evaluate the cosmetic grading by plastic surgeons. Patients' satisfaction are assessed by questionnaire (BREAST-Q) at the 6-month visit.

Citation Format: Lee J, Park HS, Kim JH, Lee DW, Song SY, Lew DH, Kim JY, Kim SI, Cho YU, Lee H, Lee KB, Yoon KH. A prospective pilot study of simultaneous robotic assisted nipple sparing mastectomy and immediate reconstruction [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-01-03.

Results of an international comparison of activity measurements of 68Ge

An international key comparison, identifier CCRI(II)-K2.Ge-68, has been performed. The National Institute of Standards and Technology (NIST) served as the pilot laboratory, distributing aliquots of a 68Ge/68Ga solution. Results for the activity concentration, CA, of 68Ge at a reference date of 12h00 UTC 14 November 2014 were submitted by 17 laboratories, encompassing many variants of coincidence methods and liquid-scintillation counting methods. The first use of 4π(Cherenkov)β-γ coincidence and anticoincidence methods in an international comparison is reported. One participant reported results by secondary methods only. Two results, both utilizing pure liquid-scintillation methods, were identified as outliers. Evaluation using the Power-Moderated Mean method results in a proposed Comparison Reference Value (CRV) of 621.7(11)kBqg-1, based on 14 results. The degrees of equivalence and their associated uncertainties are evaluated for each participant. Several participants submitted 3.6mL ampoules to the BIPM to link the comparison to the International Reference System (SIR) which may lead to the evaluation of a Key Comparison Reference Value and associated degrees of equivalence.

Evaluation of abundance of artificial radionuclides in food products in South Korea and sources

Food samples are collected nationwide from January 2016 to February 2017 and their contents of artificial radionuclides are measured to address the growing concerns regarding the radioactive contamination of food products in Korea. Specifically, 900 food samples are collected for this study and their contents of representative artificial radionuclides ¹³⁴Cs, ¹³⁷Cs, ^239,240Pu, and ⁹⁰Sr are analyzed. The analysis shows that the activity concentrations of ¹³⁷Cs in fish range from minimum detectable activity (MDA) to 340 mBq/kg of fresh weight. The concentration factor (CF) determined for ¹³⁷Cs as a measure of its bioavailability is calculated to be ca. 74 and found to be very similar to that (100) recommended by the International Atomic Energy Agency. With an MDA of <0.221 mBq/kg, the results reveal that ^239,240Pu values in fish are below the MDA. The activity concentrations of ¹³⁷Cs and ⁹⁰Sr are lower than the MDA in both shellfish and seaweed, while the activity concentrations of ^239,240Pu in shellfish range from 0.26 to 2.18 mBq/kg, and for seaweed samples range from 2.07 to 3.38 mBq/kg. The atom ratios of ²⁴⁰Pu/²³⁹Pu in shellfish caught at the Korean coast vary from 0.209 to 0.237, with a mean of 0.227. The higher ²⁴⁰Pu/²³⁹Pu atom ratio determined in shellfish is thought to be caused by the plutonium transported from the Pacific Proving Grounds rather than other sources such as the Fukushima nuclear power plant accident. The activity concentrations of ¹³⁷Cs in mushrooms are found to vary from 1.0 to 21.4 Bq/kg, with the highest concentrations observed in the Oak (shiitake) and Sarcodon asparatus. ¹³⁴Cs is detected in three mushroom specimens collected from Jeju Island and about 3-3.6% of ¹³⁷Cs present in the wild mushrooms native to the Jeju Island are introduced as a result of the Fukushima nuclear plant accident. The annual effective doses of ¹³⁷Cs received through consumption of mushrooms and fish are 2.0 × 10^-4 mSv yr^-1 and 3.9 × 10^-5 mSv yr^-1, and those values are negligible compared to the annual effective doses limit of 1 mSv yr^-1.

Systematic influences on the areas of peaks in gamma-ray spectra that have a large statistical uncertainty

A method is presented for calculating the expected number of counts in peaks that have a large relative peak-area uncertainty and appear in measured gamma-ray spectra. The method was applied to calculations of the correction factors for peaks occurring in the spectra of radon daughters. It was shown that the factors used for correcting the calculated peak areas to their expected values decrease with an increasing relative peak-area uncertainty. The accuracy of taking the systematic influence inducing the correction factors into account is given by the dispersion of the correction factors corresponding to specific peaks. It was shown that the highest accuracy is obtained in the peak analyses with the GammaVision and Gamma-W software.

How well are we managing fragility hip fractures? A narrative report on the review with the attempt to setup a Fragility Fracture Registry in Hong Kong

INTRODUCTION

In setting up a disease registry for fragility fractures in Hong Kong, we conducted a retrospective systematic study on the management of fragility hip fractures. Patient outcomes were compared with the standards from our orthopaedic working group and those from the British Orthopaedic Association that runs a mature fracture registry in the United Kingdom.

METHODS

Clinical data on fragility hip fracture patients admitted to six acute major hospitals in Hong Kong in 2012 were captured. These included demographics, pre- and post-operative assessments, discharge details, complications, and 1-year follow-up information. Analysis was performed according to the local standards with reference to those from the British Orthopaedic Association.

RESULTS

Overall, 91.0% of patients received orthopaedic care within 4 hours of admission and 60.5% received surgery within 48 hours. Preoperative geri-orthopaedic co-management was received by 3.5% of patients and was one of the reasons for the delayed surgery in 22% of patients. Only 22.9% were discharged with medication that would promote bone health. Institutionalisation on discharge significantly increased by 16.2% (P<0.001). Only 35.1% of patients attended out-patient follow-up 1 year following fracture, and mobility had deteriorated in 69.9% compared with the premorbid state. Death occurred in 17.3% of patients within a year of surgery compared with 1.6% mortality rate in a Hong Kong age-matched population.

CONCLUSIONS

The efficiency and quality of acute care for fragility hip fracture patients was documented. Regular geri-orthopaedic co-management can enhance acute care. Much effort is needed to improve functional recovery, prescription of bone health medications, attendance for follow-up, and to decrease institutionalisation. A Fracture Liaison Service is vital to improve long-term care and prevent secondary fractures.

At the Atrioventricular Crossroads: Dual Pathway Electrophysiology in the Atrioventricular Node and its Underlying Heterogeneities

The atrioventricular node (AVN) is a complex structure that performs a variety of functions in the heart. The AVN is primarily an electrical gatekeeper between the atria and ventricles and introduces a delay between atrial and ventricular excitation, allowing for efficient ventricular filling. The AVN is composed of several compartments that safely transmit electrical excitation from the atria to the ventricles via the fast or slow pathways. There are many electrophysiological differences between these pathways, including conduction time and electrical refractoriness, that increase the predisposition of the atrioventricular junction to arrhythmias such as atrioventricular nodal re-entrant tachycardia. These varied electrophysiological characteristics of the fast and slow pathways stem from their unique structural and molecular composition (tissue and cellular geometry, ion channels and gap junctions). This review summarises the structural and molecular heterogeneities of the human AVN and how they result in electrophysiological variations and arrhythmias.

Chronic kidney disease and high eGFR according to body composition phenotype in adults with normal BMI

BACKGROUND AND AIMS

Body composition contributes to the risk of chronic kidney disease (CKD) and glomerular hyperfiltration. In adults with normal body mass index (BMI), the relationships of body composition with CKD and high estimated glomerular filtration rate (eGFR) are largely unknown.

METHODS AND RESULTS

We analyzed 10,734 adults from the Korean National Health and Nutrition Examination Survey (KNHANES), whose body mass index (BMI) was within the normal range (18.5-24.9 kg/m²). Body composition was categorized into four phenotypes (normal, sarcopenia alone, obesity alone, and sarcopenic obesity) based on appendicular lean mass index (ALMI) and total body fat percentage (TBF%) measured by dual-energy X-ray absorptiometry (DXA). We examined the relationship of CKD and high eGFR (eGFR ≥ 120 ml/min per 1.73 m²) with body composition phenotypes. Sarcopenia alone (14.3%), obesity alone (16.0%), and sarcopenic obesity (10.7%) were prevalent. The association between sarcopenia alone and eGFR was J-shaped, while that between sarcopenic obesity and eGFR was U-shaped. In multivariate logistic regression analysis compared with the normal phenotype, sarcopenic obesity had an elevated odds ratio (OR) for CKD (OR: 1.59, 95% CI: 1.16-2.19). Sarcopenia alone (OR: 1.87; 95% CI: 1.41-2.47) and sarcopenic obesity (OR: 2.37, 95% CI: 1.68-3.36) had elevated OR for high eGFR.

CONCLUSION

These findings suggest that decreased muscle mass and coexistence with excess adiposity show associations with CKD and high eGFR even in adults with normal BMI. Body composition measured by DXA could provide information on the relationship of body composition with CKD and high eGFR.

4-n-butylresorcinol enhances proteolytic degradation of tyrosinase in B16F10 melanoma cells

OBJECTIVE

4-n-butylresorcinol is a competitive inhibitor of tyrosinase and has been used as an antimelanogenic agent. However, its inhibition mechanism in intact cells is not fully understood. To elucidate the cellular mechanism, we compared in vitro and in vivo inhibitory effects of 4-n-butylresorcinol on tyrosinase activity.

METHODS

B16F10 melanoma cells were cultured in media containing α-MSH in the presence or absence of 4-n-butylresorcinol. Tyrosinase mRNA levels, protein levels and activity in B16F10 cells were compared by real-time PCR, immunostaining combined with western blot and colorimetric analysis, respectively. Melanin concentration was measured by colorimetry both in the cells and in the media. Tyrosinase glycosylation and proteolytic degradation were analysed by immunoblotting after cells were treated with Endo H/PNGase F and E64/proteasome inhibitors, respectively.

RESULTS

4-n-butylresorcinol inhibited tyrosinase activity and melanin synthesis more effectively in intact cells than in cell lysates. Western blotting and real-time RT-PCR showed that 4-n-butylresorcinol reduced protein levels, but not mRNA levels, of tyrosinase in B16F10 cells. 4-n-butylresorcinol showed no effect on the processing of tyrosinase glycosylation or on trafficking to melanosomes. However, treatment of B16F10 cells with E64 or proteasome inhibitor abrogated the 4-n-butylresorcinol-induced decrease of tyrosinase. Moreover, 4-n-butylresorcinol activated p38 MAPK, resulting in increased ubiquitination of tyrosinase.

CONCLUSION

4-n-butylresorcinol inhibits melanogenesis by enhancing proteolytic degradation of tyrosinase as well as competitive binding to tyrosinase. These findings will help to develop new, effective and safe chemicals for the treatment of hyperpigmentation disorders.

Inexplicable Outcome of Early Appearance of Hepatocellular Carcinoma in the Allograft After Deceased Donor Liver Transplantation: A Case Report

BACKGROUND

This case represents the earliest appearance of de novo HCC after liver transplantation (OLT) compared with cases of previously reported literatures.

CASE REPORT

A 45-year-old man underwent deceased donor OLT owing to decompensated liver cirrhosis. He had YMDD viral mutation and hepatitis B (HBV) and C (HCV) coinfection but no tumor was found in the liver on MRI before OLT. The donor was a healthy young female donor who was HCV and HBV negative. There was no tumor in the explant liver. After OLT, HCV RNA and hepatitis B surface antigen became undetectable with DNA-positive HBV. Nine months after OLT, a computed tomography (CT) scan was performed owing to abdominal pain, detecting a mass occupying the right lobe that depicted enhanced characteristics typical of HCC. The chest CT demonstrated metastatic lung nodules in the right basal lower lobe. Fluorescence in situ hybridization showed tumor cells from the recipient.

CONCLUSIONS

To the best of our knowledge, this is the first report of de novo hepatocellular carcinoma that has emerged within a short period of undergoing OLT.

Centrality-Dependent Modification of Jet-Production Rates in Deuteron-Gold Collisions at √[s(NN)]=200 GeV

Jet production rates are measured in p+p and d+Au collisions at sqrt[s_{NN}]=200  GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Jets are reconstructed using the R=0.3 anti-k_{t} algorithm from energy deposits in the electromagnetic calorimeter and charged tracks in multiwire proportional chambers, and the jet transverse momentum (p_{T}) spectra are corrected for the detector response. Spectra are reported for jets with 12<p_{T}<50  GeV/c, within a pseudorapidity acceptance of |η|<0.3. The nuclear-modification factor (R_{dAu}) values for 0%-100% d+Au events are found to be consistent with unity, constraining the role of initial state effects on jet production. However, the centrality-selected R_{dAu} values and central-to-peripheral ratios (R_{CP}) show large, p_{T}-dependent deviations from unity, challenging the conventional models that relate hard-process rates and soft-particle production in collisions involving nuclei.

Preparation of gaseous CRMs from the primary system for (222)Rn activity measurement

For disseminating the gaseous radon standard traceable to the KRISS primary system based on the defined solid angle counting method, two kinds of radon CRM (a glass ampule type and a stainless steel cylinder type) were developed. The activity of the CRM was certified by subtracting a residual activity from the measured activity by the primary system. After certification, the ampule CRM was used to calibrate a radon-monitoring instrument and the cylinder CRM to calibrate an HPGe system. We also improved the measurement procedure of the radon primary system. In a typical radon energy spectrum, the radon peak overlaps with the polonium peak. For more reliable and accurate measurement of radon activity, a fitting method was adopted for the evaluation of radon area in the alpha energy spectrum. The result of radon activity evaluated by using the fitting method is in good agreement with that by the previous integration method.

Development of an optimized Compton suppression gamma-ray spectrometric system using Monte Carlo simulation

We have chosen to establish the Compton Suppression Spectrometer (CSS) for low activity environmental samples with a high purity germanium (HPGe) primary detector and a removable plug-in detector (NaI(Tl)) surrounded with a cylindrical annulus guard detector (NaI(Tl)). Monte Carlo simulation with PENELOPE (PENetration and Energy LOss of Positrons and Electrons) is used to determine the optimal geometry of the CSS. To verify a correlation between experiment and simulation, the energy distribution of (137)Cs and (60)Co point sources is measured and simulated for each condition. The CSS parameters are studied to determine optimal detector geometry and Compton Suppression Factor (CSF). The timing resolution of the CSS was found to be 44ns (FWHM), which is an outstanding result in the semiconductor-based gamma-ray spectrometry. All measured values of CSF agree within 5% with the values obtained from the simulation. The optimum geometry and CSF values are discussed.

New method to incorporate Type B uncertainty into least-squares procedures in radionuclide metrology

We discuss a new method to incorporate Type B uncertainty into least-squares procedures. The new method is based on an extension of the likelihood function from which a conventional least-squares function is derived. The extended likelihood function is the product of the original likelihood function with additional PDFs (Probability Density Functions) that characterize the Type B uncertainties. The PDFs are considered to describe one's incomplete knowledge on correction factors being called nuisance parameters. We use the extended likelihood function to make point and interval estimations of parameters in the basically same way as the least-squares function used in the conventional least-squares method is derived. Since the nuisance parameters are not of interest and should be prevented from appearing in the final result, we eliminate such nuisance parameters by using the profile likelihood. As an example, we present a case study for a linear regression analysis with a common component of Type B uncertainty. In this example we compare the analysis results obtained from using our procedure with those from conventional methods.

Clarification of the calculation of minimum detectable activity in low-level radioactivity measurements

We discuss a new method to determine the value of minimum detectable activity (MDA) in low-level measurements. The method is based on the Feldman-Cousins unified approach which effectively combines the construction of confidence intervals with the determination of the decision threshold and MDA. The new method requires a single probability to be pre-specified for the determination of MDA as well as decision threshold and confidence interval, in contrast with the ISO 11929 method requiring three probabilities.

Low serum magnesium is associated with coronary artery calcification in a Korean population at low risk for cardiovascular disease

BACKGROUND AND AIMS

Previous studies suggested an association between low serum magnesium levels and metabolic or cardiovascular disease. Additionally, several studies have shown that low serum magnesium is associated with vascular calcification, but there are no studies exploring its relation to coronary artery calcification (CAC). We investigated the relationship between low serum magnesium and CAC by using health examination data.

METHODS AND RESULTS

We cross-sectionally analyzed 34,553 participants who underwent coronary multi-detector computed tomography and serum magnesium level measurement in 2010-2012 as part of a health examination program at a tertiary hospital in Korea. CAC was defined as a coronary artery calcium score > 100. Participants were divided into three groups according to their serum magnesium level as follows: low < 1.9 mg/dL (n = 931), normal = 1.9-2.3 mg/dL (n = 32,341), and high > 2.3 mg/dL (n = 1281). The percentages of participants with CAC were 3.7, 1.5, and 2.3 in each group, respectively. According to multivariate analysis, low serum magnesium was associated with CAC after adjustment for age, sex, BMI, diabetes, hypertension, cardiovascular disease, systolic BP, LDL cholesterol, HDL cholesterol, eGFR, serum calcium and phosphorus, hsCRP, current smoking status, alcohol intake and vigorous exercise frequency. The odds ratio for CAC in the low serum magnesium group compared to the normal group was 2.10 (1.40-3.15, P < 0.001).

CONCLUSION

Low serum magnesium level is associated with CAC in a Korean population at low risk for cardiovascular disease. Further studies are needed to generalize this finding and to verify the causal relationship between low serum magnesium and CAC.

Measurements of Elliptic and Triangular Flow in High-Multiplicity 3He+Au Collisions at √(s(NN))=200 GeV

We present the first measurement of elliptic (v(2)) and triangular (v(3)) flow in high-multiplicity (3)He+Au collisions at √(s(NN))=200  GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in (3)He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the (3)He+Au system. The collective behavior is quantified in terms of elliptic v(2) and triangular v(3) anisotropy coefficients measured with respect to their corresponding event planes. The v(2) values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three (3)He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

Measurement of Long-Range Angular Correlation and Quadrupole Anisotropy of Pions and (Anti)Protons in Central d+Au Collisions at sqrt[s_{NN}]=200 GeV

We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sqrt[s_{NN}]=200 GeV. The charged hadron is measured at midrapidity |η|<0.35, and the energy is measured at large rapidity (-3.7<η<-3.1, Au-going direction). An enhanced near-side angular correlation across |Δη|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v_{2} for inclusive charged hadrons at midrapidity up to p_{T}=4.5 GeV/c. We also present the measurement of v_{2} for identified π^{±} and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sqrt[s_{NN}]=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.

Search for bosonic superweakly interacting massive dark matter particles with the XMASS-I detector

Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4)  kg-1 keVee-1 day-1 in the detector.