Treatment strategy for splenic artery aneurysms and novel classification based on imaging.

OBJECTIVE: The incidence of splenic artery aneurysms (SAAs) has increased with advances in imaging techniques, necessitating a comprehensive classification to guide treatment strategies. This study aims to propose a novel classification system for SAAs based on aneurysm characteristics and to review treatment outcomes at our center. METHODS: This retrospective study included 113 patients with SAAs admitted to Peking Union Medical College Hospital from January 2019 to December 2023, assessed using computed tomography angiography or digital subtraction angiography. A new classification system was devised based on the aneurysm location, morphology, integrity, and parent artery anatomy. Treatment strategies were determined based on these characteristics, with interventions ranging from endovascular therapy to laparoscopic and open surgery. Patients were followed up after the intervention to assess mortality, complications, reinterventions, and aneurysm-related outcomes. RESULTS: The study cohort of 113 patients with 127 SAAs had a predominance of female patients (63.7%) and a mean age of 52.7 years. The SAAs were classified into five types, with type I being the most common. The intervention techniques varied across types, with sac embolization, covered stent implantation, and artery embolization being the most frequently used. The overall technical success rate was 94.7%, with perioperative complication and reintervention rates of 25.0% and 0.9%, respectively, and no deaths within 30 days after the intervention. The median follow-up duration was 21 months, with overall complications rate of 3.5% and no aneurysm-related complications or deaths. CONCLUSIONS: The proposed classification system effectively guides the selection of treatment strategies for SAAs, incorporating key anatomical and morphological features. This system facilitated high technical success and low complication rates, underscoring the importance of tailored techniques in managing SAAs.

Endovascular Embolization for Idiopathic Serial Right Internal Mammary Artery Aneurysms.

CLINICAL IMAPCT: This article showed images of a patient with idiopathic serial right internal mammary artery true aneurysms treated by endovascular embolization, which is a rare diagnosis and should be considered in differential diagnosis of paratracheal mass.

Risk Factors for Access-Related Adverse Events Related to the Preclose Technique in Thoracic Endovascular Aortic Repair.

PURPOSE: To analyze the risk factors for access-related adverse events (AEs) of the preclose technique in thoracic endovascular aortic repair (TEVAR). MATERIALS AND METHODS: Ninety-one patients with Stanford type B aortic dissection who underwent the preclose technique in TEVAR between January 2013 and December 2021 were included. According to the occurrence of access-related AEs, the patients were divided into 2 groups: those with AE and those without AE. Age, sex, combined diseases, body mass index, skin depth, femoral artery diameter, access calcification, iliofemoral artery tortuosity, and sheath size were recorded for risk factor analysis. The sheath-to-femoral artery ratio (SFAR), the ratio of the femoral artery inner diameter (in millimeters) to the sheath's outer diameter (in millimeters), was also included in the analysis. RESULTS: SFAR was identified as an independent risk factor for AEs using multivariable logistic analysis (odds ratio, 251.748; 95% CI, 7.004-9,048.534; P = .002). The cutoff value of SFAR was 0.85 and was related to a higher incidence of access-related AEs (5.2% vs 33.3%, P = .001), especially to a higher stenosis rate (0.0% vs 21.2%, P = .001). CONCLUSIONS: SFAR is an independent risk factor for access-related AEs of preclose in TEVAR with a cutoff value of 0.85. SFAR could be a new criterion for preoperative access evaluation in high-risk patients that may allow the detection and treatment of access-related AEs at the early stage.

Placement of Bare Self-Expanding Metal Stent for Isolated Superior Mesenteric Artery Dissection.

BACKGROUND: To evaluate the safety and efficacy of placing bare self-expanding metal stent (SEMS) for treating isolated superior mesenteric artery dissection (ISMAD). METHOD: Patients with ISMAD who received bare SEMS from January 2014 to December 2021 at the authors' center were included. Baseline characteristics, clinical manifestation, radiological findings, and treatment outcomes, including symptom relief and SMA remodeling, were analyzed. RESULT: A total of 26 patients were included in this study. Among the patients, 25 were admitted due to persistent abdominal pain, and 1 was admitted based on computed tomography angiography (CTA) during physical examination. According to CTA scan, the percentage of stenosis was 91% (53.8-100%), and the length of dissection was 100.2 ± 8.4 mm. All patients received bare SEMS placement. The median time to symptom relief was 1 day (interquartile range, 1 3 days). The the median follow-up time of CTA was 6.8 months (range, 2-85 months), with an average of 16.2 months. Complete remodeling of the superior mesenteric artery (SMA) was recorded in 24 patients. The median time to remodeling was 3 months with an average of 4.7 months. Survival analysis indicated no significance difference in remodeling time between different ISMAD types based on Yun classification (P = 0.888) or between acute and nonacute disease (P = 0.423). Incomplete remodeling was noted in 2 patients. Distal stent occlusion without SMA-related symptoms was seen in 1 patient. Proximal stent stenosis occurred in 1 patient, and restenting was performed. The median follow-up time by telephone was 20.8 (4-91.5) months, and no intestinal ischemic symptoms were observed in any patient. CONCLUSIONS: Bare SEMS placement can effectively relieve SMA-related symptoms in a short time and promote dissection remodeling in ISMAD. Time from symptom onset and classification of ISMAD seem not to have effects on SMA remodeling after bare SEMS placement.

Analysis of Low-Frequency 1/f Noise Characteristics for MoTe2 Ambipolar Field-Effect Transistors.

Low-frequency electronic noise is an important parameter used for the electronic and sensing applications of transistors. Here, we performed a systematic study on the low-frequency noise mechanism for both p-channel and n-channel MoTe2 field-effect transistors (FET) at different temperatures, finding that low-frequency noise for both p-type and n-type conduction in MoTe2 devices come from the variable range hopping (VRH) transport process where carrier number fluctuations (CNF) occur. This process results in the broad distribution of the waiting time of the carriers between successive hops, causing the noise to increase as the temperature decreases. Moreover, we found the noise magnitude for p-type MoTe2 FET hardly changed after exposure to the ambient conditions, whereas for n-FET, the magnitude increased by nearly one order. These noise characteristics may provide useful guidelines for developing high-performance electronics based on the emerging transition metal dichalcogenides.