Moths in space: The below-canopy structure of forest drives abundance and mobility-related traits of moth communities

The distribution of species is primarily driven by the availability of trophic resources. In a given forest type, insects trophically related to the dominant tree are expected to be evenly distributed due to the abundance of their foodplant. However, their distribution is also influenced by complex relationships with abiotic and biotic parameters such as available space, predatory pressure, and morphometric traits. In this study, we investigated how the three-dimensional structure of space below the canopy may affect the composition of nocturnal lepidoptera communities. To synthesise the complexity of the dispersal behaviour of these insects, we evaluated easily measurable traits such as wingspan and the presence of tympanic organs, both connected to their mobility and thus potentially influenced by the structure of the available flight space. The study was conducted in the Sila National Park (Italy), where 12 sampling sites were selected in pine forests and an additional 12 in beech forests. Forest spatial structure was investigated using a portable terrestrial laser scanner. Moths were sampled monthly using light traps from May to October in both 2019 and 2020. Among measured forest traits, we observed that the space above three meters from the ground is the only factor influencing community composition. Larger species with tympanic organs prefer environments with less space below tree canopies. Our findings could be the starting point for future studies that investigate a potential defence strategy of moths against bats, as tympanate and larger species not only actively avoid chiropter predation but could also choose denser forests because of a lower bat activity. Moths' distribution and community composition thus appear to be significantly shaped by the spatial structure of forests.

Clinical experience in intracranial stenting of Wingspan stent system under local anesthesia

Objective

The use of endovascular treatments for symptomatic intracranial atherosclerosis disease (ICAD) remains contentious due to high periprocedural complications. Many centers resort to general anesthesia for airway protection and optimal periprocedural conditions; however, this approach lacks real-time monitoring of patients' neurological status during procedures. In this study, we employed intracranial stenting with the Wingspan system under local anesthesia to address this challenge.

Methods

We conducted a retrospective study of 45 consecutive ICAD patients who underwent intracranial stenting with the Wingspan system at our hospital from August 2013 to May 2021. These stenting procedures were performed under local anesthesia in a hybrid operation room. Neurological assessments were conducted during the procedure. The patients with periprocedural complications were analyzed for the risk factors.

Results

The study included 45 ICAD patients (median age 62 years; 35 male and 10 female individuals). Among them, 30 patients had anterior circulation ICAD, and 15 had posterior circulation ICAD. The periprocedural complication rate was 8.9% (4/45), with an overall mortality rate of 2.2% (1/45). Notably, no procedure-related perforation complications were found, and all ischemic complications occurred in the perforating bearing artery, specifically in patients with stents placed in the middle cerebral artery or basilar artery, while no complications were observed in the non-perforating bearing artery of the internal carotid artery and vertebral artery (p = 0.04).

Conclusion

Our study demonstrates the safety and efficacy of the Wingspan stent system when performed on selected patients under local anesthesia. This approach seems to reduce procedural-related morbidity and be a safe intervention. In addition, it is crucial for surgeons to be aware that patients with perforator-bearing artery stenosis may be at a higher risk of complications.

Japanese Postmarket Surveillance of Percutaneous Transluminal Angioplasty and Wingspan Stenting for Intracranial Atherosclerotic Disease

BACKGROUND

The Wingspan stent system was approved as a rescue device for angioplasty of intracranial atherosclerotic disease (ICAD) in 2012. We conducted the government-recommended Japanese Postmarket Surveillance of Percutaneous Transluminal Angioplasty and Wingspan Stenting for Intracranial Atherosclerotic Disease to monitor Wingspan safety and performance.

METHODS

In this open-label, single-arm study at 76 centers in Japan, ICAD subjects were treated with the Wingspan stent between 2014 and 2016. Efficacy end points were successful stent deployment and technical success, defined as stenosis improvement to <50%. Safety end points were ischemic stroke, modified Rankin Scale and National Institutes of Health Stroke Scale scores, adverse events, and mortality. Subjects were considered treated outside of current recommendations if not already receiving antithrombotics or if percutaneous transluminal angioplasty and stenting occurred within 7 days of onset.

RESULTS

The safety cohort included 305 subjects (mean age: 68.7 + 9.6; 83.3% male). Four subjects were removed due to being out of contract. Therefore, 301 subjects were included (mean age: 68.7 ± 9.7; 84.1% male). Successful stent placement was 96.7%. Technical success was observed in 86.8% of lesions. At 1 year, the rate of restenosis was 15.7%, ischemic stroke was 3.9%, and any stroke was 7.9%. Functionally independent outcome (modified Rankin Scale: 0-2) was 88.9% and mortality 3.0%. Significantly more serious adverse events occurred in subjects treated outside of current recommendations (17.9%) versus subjects treated per current recommendations (8.8%) (P = 0.045).

CONCLUSIONS

Endovascular treatment using the Wingspan stent for ICAD is safe and effective in the Japanese population.

Anterior cerebral artery dissection for a patient with ipsilateral aplastic or twig-like middle cerebral artery: An illustrative case report

Background

An aplastic or twig-like middle cerebral artery (Ap/T-MCA) is a rare anomaly, which sometimes causes ischemic infarction. Collateral flow from the ipsilateral anterior cerebral artery (ACA) is important for patients with Ap/T-MCA. If ipsilateral ACA stenosis or occlusion occurs, a large infarction with a wider field than the ACA territory could happen. First, mechanical thrombectomy was performed for the right ACA near occlusion caused by arterial dissection with ipsilateral Ap/T-MCA in this case. Second, Wingspan stenting was performed for the right ACA restenosis.

Case Description

A 77-year-old female presented to the hospital with the left hemiparesis. We diagnosed a right ACA infarction caused by right ACA occlusion. Digital subtraction angiography showed right Ap/T-MCA and ipsilateral ACA near occlusion. Thrombectomy was performed, and recanalization was achieved with mild ACA stenosis. The lesion was the dissection due to angiographical finding. Two months after treatment, transient left hemiparesis occurred and right ACA stenosis progressed. Computed tomography perfusion showed hypoperfusion of the right hemisphere. Wingspan stenting was performed from the left internal carotid artery through the anterior communicating artery with an intermediate catheter. The patient was discharged without any neurological deficit.

Conclusion

We reported the first case of a patient who underwent Wingspan stenting for the right ACA dissection with Ap/T-MCA. Short-term follow-up and aggressive intervention should be considered for collateral pathway dissection with Ap/T-MCA because the symptoms can become serious. The patients with Ap/T-MCA should be cautious about the collateral pathway arterial changes in particular ipsilateral ACA due to the increasing hemodynamic stress.

Dilation of proximal internal carotid artery collapse due to severe distal stenosis after angioplasty for distal stenosis: A case report

Background

We report a case of proximal internal carotid artery (ICA) collapse due to severe distal stenosis that dilated after angioplasty for distal stenosis.

Case Description

A 69-year-old woman underwent thrombectomy for the left ICA occlusion due to stenosis of C3 portion and was discharged home with a modified Rankin Scale score of 0. One year later, she developed cerebral infarction due to progressive stenosis of the C3 portion of the left ICA with proximal ICA collapse and underwent emergency percutaneous transluminal angioplasty (PTA) for distal stenosis. Device guidance to the stenosis was difficult due to proximal ICA collapse. After PTA, blood flow in the left ICA increased, and proximal ICA collapse dilated over time. Due to severe residual stenosis, she underwent more aggressive PTA followed by Wingspan stenting. Device guidance to the residual stenosis was facilitated because proximal ICA collapse had already dilated. Six months later, proximal ICA collapse further dilated.

Conclusion

PTA for severe distal stenosis with proximal ICA collapse may result in dilation of proximal ICA collapse over time.

A Comparison of Safety and Effectiveness Between Wingspan and Neuroform Stents in Patients With Middle Cerebral Artery Stenosis

Background: Percutaneous transluminal angioplasty and stenting with the Wingspan stent has proven safe and effective in patients with middle cerebral artery stenosis (MCAS), but the off-label use of the Neuroform stent might be an alternative treatment. This study aimed to compare the safety and effectiveness of the above two intracranial stents in patients with MCAS. Methods: We retrospectively analyzed consecutive patients with symptomatic MCAS who had been treated with the Neuroform EZ or the Wingspan stent. A propensity score was generated to control for differences in baseline characteristics. The endpoints were the rate of peri-procedural complications within 30 days after stenting, the in-stent restenosis rate, and any target-vessel-related stroke or deaths during follow-up. Results: After matching for propensity score, the peri-procedural complication rate in the Wingspan group was 7.4% compared with 5.6% in the Neuroform group (p = 1.00), while the follow-up in-stent restenosis rates were 23.3 vs. 14.3%, respectively (p = 0.41). In the restenosis group, the patients tended to be younger (p < 0.01) and the degree of artery stenosis before stenting was higher (p < 0.01). Conclusion: This study indicated that in patients with symptomatic MCAS, Neuroform EZ stents are an alternative to Wingspan. Moreover, younger age and higher degree of artery stenosis before stenting might be a risk factor of in-stent restenosis.

A novel technique for stenting in cases of refractory intracranial stenosis

Endovascular management of intracranial stenosis is one of the most controversial subjects in neurointervention. Previous level 1 evidence shows superiority of medical management but more recent studies have shown improved outcomes in selective patients. We describe a case demonstrating a new method for stenting of intracranial stenosis using a single system with Coyote angioplasty balloon (Boston Scientific) and the Atlas stent (Stryker).

Wingspan stent delivery catheter fracture and the TRAP technique for endovascular salvage

Background Intracranial atherosclerotic disease may result in ischemic infarction and has a high rate of recurrent ischemic strokes despite medical therapy. Patients who fail medical therapy may undergo endovascular treatment with cerebral artery angioplasty and possible Wingspan stent placement. We present a unique case of Wingspan delivery microcatheter fracture that resulted in a retained foreign body and an endovascular salvage maneuver. Case description An elderly patient presented with an acute ischemic stroke due to a severe stenosis in the proximal left middle cerebral artery (MCA). The patient failed non-invasive medical treatment and underwent endovascular treatment with angioplasty and Wingspan stent placement. Following Wingspan stent deployment, the stent delivery catheter fractured, and the retained catheter fragment resulted in MCA occlusion. The foreign body was retrieved by balloon catheter inflation within an intermediate catheter adjacent to the proximal end of the fractured catheter and removal of the entire construct (TRAP technique). Conclusions Wingspan delivery microcatheter fracture is a rare event. The TRAP technique may be used for successful retrieval of a retained foreign body.

Stenting and angioplasty of small cerebral arteries in symptomatic intracranial atherosclerotic disease

BACKGROUND

Intracranial atherosclerotic disease (ICAD) is a common cause of stroke with a poor natural history despite medical therapy. Few studies have investigated endovascular therapies for the treatment of symptomatic ICAD in distal intracranial arteries. Here, we present the feasibility and safety of balloon angioplasty with and without stenting in patients with medically refractory small artery symptomatic ICAD.

METHOD

Personal logs were reviewed to identify patients who were treated for small artery ICAD (stenosis > 50%) using angioplasty ± stenting. Small cerebral arteries were defined by a diameter ≤ 2 mm or any branch distal to a large intracranial vessel (i.e. distal to ICA, M1, A1, Vertebrobasilar trunk). Patient characteristics, clinical manifestations, treatment, hospital course, and follow up data was collected and analyzed.

RESULTS

Ten patients (12 arteries) were treated with either primary balloon angioplasty (58.3%) or angioplasty with stenting (41.6 %) with 100% technical success rate. Mean pre-treatment stenosis was 79.9% while mean post-treatment stenosis was 19.0%. There were no major peri-procedural complications including symptomatic intracranial hemorrhage or mortality; three cases were complicated by groin hematoma. Patients were followed for a mean total of 18.6 months with only one symptomatic restenosis which was re-treated successfully. All patients had good functional outcome with a mRS of either 0 (80%) or 1 (20%) on follow up.

CONCLUSION

In our case series, treatment of symptomatic small artery ICAD with angioplasty ± stenting was safe and effective. These interventions should be considered as an alternative treatment for ICAD patients refractory to medical therapy.

Endovascular treatment of symptomatic intracranial atherosclerotic disease

Symptomatic intracranial atherosclerotic disease (ICAD) is responsible for approximately 10% of all ischemic strokes in the United States. The risk of recurrent stroke may be as high as 35% in patient with critical stenosis >70% in diameter narrowing. Recent advances in medical and endovascular therapy have placed ICAD at the forefront of clinical stroke research to optimize the best medical and endovascular approach to treat this important underlying stroke etiology. Analysis of symptomatic ICAD studies lead to the question that whether angioplasty and/or stenting is a safe, suitable, and efficacious therapeutic strategy in patients with critical stenoses that are deemed refractory to medical management. Most of the currently available data in support of angioplasty and/or stenting in high risk patients with severe symptomatic ICAD is in the form of case series and randomized trial results of endovascular therapy versus medical treatment are awaited. This is a comprehensive review of the state of the art in the endovascular approach with angioplasty and/or stenting of symptomatic ICAD.