Rise of Ruppia in Chesapeake Bay: Climate change-driven turnover of foundation species creates new threats and management opportunities.

Global change has converted many structurally complex and ecologically and economically valuable coastlines to bare substrate. In the structural habitats that remain, climate-tolerant and opportunistic species are increasing in response to environmental extremes and variability. The shifting of dominant foundation species identity with climate change poses a unique conservation challenge because species vary in their responses to environmental stressors and to management. Here, we combine 35 y of watershed modeling and biogeochemical water quality data with species comprehensive aerial surveys to describe causes and consequences of turnover in seagrass foundation species across 26,000 ha of habitat in the Chesapeake Bay. Repeated marine heatwaves have caused 54% retraction of the formerly dominant eelgrass (Zostera marina) since 1991, allowing 171% expansion of the temperature-tolerant widgeongrass (Ruppia maritima) that has likewise benefited from large-scale nutrient reductions. However, this phase shift in dominant seagrass identity now presents two significant shifts for management: Widgeongrass meadows are not only responsible for rapid, extensive recoveries but also for the largest crashes over the last four decades; and, while adapted to high temperatures, are much more susceptible than eelgrass to nutrient pulses driven by springtime runoff. Thus, by selecting for rapid post-disturbance recolonization but low resistance to punctuated freshwater flow disturbance, climate change could threaten the Chesapeake Bay seagrass' ability to provide consistent fishery habitat and sustain functioning over time. We demonstrate that understanding the dynamics of the next generation of foundation species is a critical management priority, because shifts from relatively stable habitat to high interannual variability can have far-reaching consequences across marine and terrestrial ecosystems.

Sequential Flow Diversion After Nitinol Stent Placement for a Large, Matricidal Cavernous Internal Carotid Artery Aneurysm: Technical Video.

The Surpass Evolve flow diverter is a novel 64-wire braided intravascular stent approved to treat unruptured large or giant saccular wide-neck or fusiform intracranial aneurysms of the intracranial internal carotid artery.1-3 Flow diverting stents have been used for the treatment of previously stented aneurysms, including residual aneurysms following prior flow diversion.5-8 This patient initially presented with a large symptomatic matricidal cavernous ICA aneurysm4 that was treated with stand-alone Neuroform Atlas stenting at an outside hospital. Here we present a video demonstrating the placement of sequential Surpass Evolve flow diverter stents within a Neuroform Atlas nitinol stent.

Direct, Indirect, and Combined Extracranial-to-Intracranial Bypass for Adult Moyamoya Disease: An Updated Systematic Review and Meta-Analysis.

BACKGROUND: Moyamoya disease is a chronic, progressive cerebrovascular disease involving occlusion or stenosis of the terminal portion of the internal carotid artery. We conducted an updated systematic review and meta-analysis to investigate clinical and angiographic outcomes comparing direct, combined, and indirect bypass for the treatment of moyamoya disease in adults. METHODS: Two independent authors performed Preferred Reporting Items for Systematic reviews and Meta-Analyses guided literature searches in December 2021 to identify articles reporting clinical/angiographic outcomes in adult moyamoya disease patients undergoing bypass. Primary end points used were ischemic and hemorrhagic strokes, clinical outcomes, and angiographic revascularization. Study quality was evaluated with Newcastle-Ottawa and the Oxford Center for Evidence-Based Medicine scales. RESULTS: Four thousand four hundred fifty seven articles were identified in the initial search; 143 articles were analyzed. There were 3827 direct, 3826 indirect, and 3801 combined bypasses. Average length of follow-up was 3.59±2.93 years. Pooled analysis significantly favored direct (odds ratio [OR], 0.62 [0.48-0.79]; P<0.0001; OR, 0.44 [0.32-0.59]; P<0.0001; OR, 0.56 [0.42-0.74]; P<0.0001; OR, 3.1 [2.5-3.8]; P=0.0001) and combined (OR, 0.53 [0.41-0.69]; P<0.0001; OR, 0.28 [0.2-0.41]; P<0.0001; OR, 0.41 [0.3-0.56]; P<0.0001; OR, 3.1 [2.8-4.3]; P=0.0001) over indirect bypass for early stroke, late stroke, late intracerebral hemorrhage, and favorable outcomes, respectively. Indirect bypass was favored over combined (OR, 3.1 [1.7-5.6]; P<0.0001) and direct (OR, 4.12 [2.34-7.25]; P<0.0001) for early intracerebral hemorrhage. The meta-analysis significantly favored direct (OR, 0.37 [0.23-0.60]; P<0.001; OR, 0.49 [0.31-0.77]; P=0.002) and combined (OR, 0.23 [0.12-0.43]; P<0.00001; OR, 0.30 [0.18-0.49]; P<0.00001) bypass over indirect bypass for late stroke and late hemorrhage, respectively. Combined bypass was favored over indirect bypass for favorable outcomes (OR, 2.06 [1.18-3.58]; P=0.01). CONCLUSIONS: Based on combined meta-analysis (43 articles) and pooled analysis (143 articles), the existing literature indicates that combined and direct bypasses have significant benefits for patients suffering from late stroke and hemorrhage versus indirect bypass. Combined bypass was favored over indirect bypass for favorable outcomes. This is a strong recommendation based on low-quality evidence when utilizing the Grades of Recommendation, Assessment, Development, and Evaluation system. These findings have important implications for bypass strategy selection.

Data synthesis for environmental management: A case study of Chesapeake Bay.

Synthesizing large, complex data sets to inform resource managers towards effective environmental stewardship is a universal challenge. In Chesapeake Bay, a well-studied and intensively monitored estuary in North America, the challenge of synthesizing data on water quality and land use as factors related to a key habitat, submerged aquatic vegetation, was tackled by a team of scientists and resource managers operating at multiple levels of governance (state, federal). The synthesis effort took place over a two-year period (2016-2018), and the results were communicated widely to a) scientists via peer review publications and conference presentations; b) resource managers via web materials and workshop presentations; and c) the public through newspaper articles, radio interviews, and podcasts. The synthesis effort was initiated by resource managers at the United States Environmental Protection Agencys' Chesapeake Bay Program and 16 scientist participants were recruited from a diversity of organizations. Multiple short, immersive workshops were conducted regularly to conceptualize the problem, followed by data analysis and interpretation that supported the preparation of the synthetic products that were communicated widely. Reflections on the process indicate that there are a variety of structural and functional requirements, as well as enabling conditions, that need to be considered to achieve successful outcomes from synthesis efforts.

Woven EndoBridge Embolized Aneurysm Clippings: 2-Dimensional Operative Video.

The Woven EndoBridge (WEB) device (MicroVention, Aliso Viejo, California) is an intrasaccular flow disruptor used for the treatment of both unruptured and ruptured intracranial aneurysms. WEB has been shown to have 54% complete and 85% adequate aneurysm occlusion rates at 1-yr follow-up.1 Residual and recurrent ruptured aneurysms have been shown to have a higher risk of re-rupture than completely occluded aneurysms.2 With increased utilization of WEB in the United States, optimizing treatment strategies of residual aneurysms previously treated with the WEB device is essential, including surgical clipping.3,4 Here, we present an operative video demonstrating the surgical clip occlusion of previously ruptured middle cerebral artery and anterior communicating artery aneurysms that had been treated with the WEB device and had sizable recurrence on follow-up angiography. Informed consent was obtained from both patients. Lessons learned include the following: (1) the WEB device is highly compressible, unlike coils; (2) proximal WEB marker may interfere with clip closure; (3) no evidence of WEB extrusion into the subarachnoid space; (4) no more scarring than expected in ruptured cases; and (5) clipping is a feasible option for treating WEB recurrent or residual aneurysms.

The Woven EndoBridge embolization device for the treatment of intracranial wide-necked bifurcation aneurysms.

Wide-necked bifurcation aneurysms are common when evaluating both ruptured and unruptured intracranial aneurysms and can pose unique challenges. The Woven EndoBridge device (recently approved in the US) is specifically designed for the treatment of these aneurysms. This article serves to introduce the device to a wider audience with a thorough review of the literature, device design, indications, pre-operative evaluation, procedural usage and potential pitfalls.

Lay abstract The Woven EndoBridge device recently received approval by the US FDA for use in certain types of difficult to treat brain aneurysms. This article is primarily a descriptive and technical article aimed at doctors who use catheter-based techniques to treat problems of the blood vessels. Initial studies show that the device is at least as effective as previously existing methods, though more research needs to be done regarding long-term outcomes.

Restoration of seagrass habitat leads to rapid recovery of coastal ecosystem services.

There have been increasing attempts to reverse habitat degradation through active restoration, but few large-scale successes are reported to guide these efforts. Here, we report outcomes from a unique and very successful seagrass restoration project: Since 1999, over 70 million seeds of a marine angiosperm, eelgrass (Zostera marina), have been broadcast into mid-western Atlantic coastal lagoons, leading to recovery of 3612 ha of seagrass. Well-developed meadows now foster productive and diverse animal communities, sequester substantial stocks of carbon and nitrogen, and have prompted a parallel restoration for bay scallops (Argopecten irradians) Restored ecosystem services are approaching historic levels, but we also note that managers value services differently today than they did nine decades ago, emphasizing regulating in addition to provisioning services. Thus, this study serves as a blueprint for restoring and maintaining healthy ecosystems to safeguard multiple benefits, including co-benefits that may emerge as management priorities over time.

Morphometric Comparison of the Pterional Trans-Sylvian and the Pretemporal Trans-Clinoidal Approaches to the Posterior Communicating Artery.

BACKGROUND: Posterior communicating (Pcom) aneurysms in the modern era have tended toward increased complexity and technical difficulties. The pretemporal approach is a valuable extension to the pterional approach for basilar apex aneurysms, but its advantages for Pcom aneurysms have not been previously elucidated. OBJECTIVE: To quantify characteristics of the pretemporal approach to the Pcom. METHODS: We dissected 6 cadaveric heads (12 sides) with a pretemporal transclinoidal approach and measured the following variables: (1) exposed length of internal carotid artery (ICA) proximal to the Pcom artery; (2) exposed circumference of ICA at the origin of Pcom; (3) deep working area between the optic nerve and tentorium/oculomotor nerve; (4) superficial working area; (5) exposure depth; and (6) the frontotemporal (superior posterolateral) and (7) orbito-sphenoidal (inferior anterolateral) angles of exposure. RESULTS: Compared with pterional craniotomy, the pretemporal transclinoidal approach increased the exposed length of the proximal ICA from 3.3 to 11.7 mm (P = .0001) and its circumference from 5.1 to 7.8 mm (P = .0003), allowing a 210° view of the ICA (vs 137.9°). The deep and superficial working areas also significantly widened from 53.7 to 92.4 mm2 (P = .0048) and 252.8 to 418.2 mm2 (P = .0001), respectively; the depth of the exposure was equivalent. The frontotemporal and spheno-Sylvian angles increased by 17° (P = .0006) and 10° (P = .0037), respectively. CONCLUSION: The pretemporal approach can be useful for complex Pcom aneurysms by providing easier proximal control, wider working space, improved aneurysm visualization, and more versatile clipping angles. Enhanced exposure results in a potentially higher rate of complete aneurysm obliteration and complication avoidance.

Safety and efficacy of brainstem biopsy in children and young adults.

OBJECTIVE: Biopsies of brainstem lesions are performed to establish a diagnosis in the setting of an atypical clinical or radiological presentation, or to facilitate molecular studies. A better understanding of the safety and diagnostic yield of brainstem biopsies would help guide appropriate patient selection. METHODS: All patients who underwent biopsy of a brainstem lesion during the period from January 2011 to June 2019 were reviewed. Demographic, radiological, surgical, and outcome data were collected. RESULTS: A total of 58 patients underwent 65 brainstem biopsies during the study period. Overall, the median age was 7.6 years (IQR 3.9-14.2 years). Twenty-two of the 65 biopsies (34%) were open, 42 (65%) were stereotactic, and 1 was endoscopic. In 3 cases (5%), a ventriculoperitoneal shunt was placed, and in 9 cases (14%), a posterior fossa decompression was performed during the same operative session as the biopsy. An intraoperative MRI (iMRI) was performed in 28 cases (43%). In 3 of these cases (11%), the biopsy was off target and additional samples were obtained during the same procedure. New neurological deficits were noted in 5 cases (8%), including sensory deficits, ophthalmoparesis/nystagmus, facial weakness, and hearing loss; these deficits persisted in 2 cases and were transient in 3 cases. A pseudomeningocele occurred in 1 patient; no patients developed a CSF leak or infection. In 8 cases (13%) an additional procedure was needed to obtain a diagnosis. CONCLUSIONS: Brainstem biopsies are safe and effective. Target selection and approach should be a collaborative effort. iMRI can be used to assess biopsy accuracy in real time, thereby allowing any adjustment if necessary.

An Analysis of Publication Productivity During Residency for 1506 Neurosurgical Residents and 117 Residency Departments in North America.

BACKGROUND: Bibliometrics is defined as the study of statistical and mathematical methods used to quantitatively analyze scientific literature. The application of bibliometrics in neurosurgery continues to evolve. OBJECTIVE: To calculate a number of publication productivity measures for almost all neurosurgical residents and departments within North America. These measures were correlated with survey results on the educational environment within residency programs. METHODS: During May to June 2017, data were collected from departmental websites and Scopus to compose a bibliometric database of neurosurgical residents and residency programs. Data related to authorship value and study content were collected on all articles published by residents. A survey of residency program research and educational environment was administered to program directors and coordinators; results were compared with resident academic productivity. RESULTS: The median number of publications in residency was 3; median h-index and Resident index were 1 and 0.17 during residency, respectively. There was a statistically significant difference in academic productivity among male neurosurgical residents compared with females. The majority of articles published were tier 1 clinical articles. Residency program research support was significantly associated with increased resident productivity (P < .001). Scholarly activity requirements were not associated with increased resident academic productivity. CONCLUSION: This study represents the most comprehensive bibliometric assessment of neurosurgical resident academic productivity during training to date. New benchmarks for individual and department academic productivity are provided. A supportive research environment for neurosurgical residents is associated with increased academic productivity, but a scholarly activity requirement was, surprisingly, not shown to have a positive effect.

Long-term nutrient reductions lead to the unprecedented recovery of a temperate coastal region.

Humans strongly impact the dynamics of coastal systems, yet surprisingly few studies mechanistically link management of anthropogenic stressors and successful restoration of nearshore habitats over large spatial and temporal scales. Such examples are sorely needed to ensure the success of ecosystem restoration efforts worldwide. Here, we unite 30 consecutive years of watershed modeling, biogeochemical data, and comprehensive aerial surveys of Chesapeake Bay, United States to quantify the cascading effects of anthropogenic impacts on submersed aquatic vegetation (SAV), an ecologically and economically valuable habitat. We employ structural equation models to link land use change to higher nutrient loads, which in turn reduce SAV cover through multiple, independent pathways. We also show through our models that high biodiversity of SAV consistently promotes cover, an unexpected finding that corroborates emerging evidence from other terrestrial and marine systems. Due to sustained management actions that have reduced nitrogen concentrations in Chesapeake Bay by 23% since 1984, SAV has regained 17,000 ha to achieve its highest cover in almost half a century. Our study empirically demonstrates that nutrient reductions and biodiversity conservation are effective strategies to aid the successful recovery of degraded systems at regional scales, a finding which is highly relevant to the utility of environmental management programs worldwide.

Intracranial chordoma presenting as acute hemorrhage in a child: Case report and literature review.

BACKGROUND: Chordomas are rare, slow-growing malignant neoplasms derived from remnants of the embryological notochord. Pediatric cases comprise only 5% of all chordomas, but more than half of the reported pediatric chordomas are intracranial. For patients of all ages, intracranial chordomas typically present with symptoms such as headaches and progressive neurological deficits occurring over several weeks to many years as they compress or invade local structures. There are only reports of these tumors presenting acutely with intracranial hemorrhage in adult patients. CASE DESCRIPTION: A 10-year-old boy presented with acute onset of headache, emesis, and diplopia. Head computed tomography and magnetic resonance imaging of brain were suspicious for a hemorrhagic mass located in the left petroclival region, compressing the ventral pons. The mass was surgically resected and demonstrated acute intratumoral hemorrhage. Pathologic examination was consistent with chordoma. CONCLUSION: There are few previous reports of petroclival chordomas causing acute intracranial hemorrhage. To the authors' knowledge, this is the first case of a petroclival chordoma presenting as acute intracranial hemorrhage in a pediatric patient. Although uncommon, it is important to consider chordoma when evaluating a patient of any age presenting with a hemorrhagic lesion of the clivus.

DHA diet reduces AD pathology in young APPswe/PS1 Delta E9 transgenic mice: possible gender effects.

Epidemiological and clinical trial findings suggest that consumption of docosahexaenoic acid (DHA) lowers the risk of Alzheimer's disease (AD). We examined the effects of short-term (3 months) DHA enriched diet on plaque deposition and synaptic defects in forebrain of young APPswe/PS1 Delta E9 transgenic (tg) and non-transgenic (ntg) mice. Gas chromatography revealed a significant increase in DHA concomitant with a decrease of arachidonic acid in both brain and liver in mice fed with DHA. Female tg mice consumed relatively more food daily than ntg female mice, independent of diet. Plaque load was significantly reduced in the cortex, ventral hippocampus and striatum of female APPswe/PS1 Delta E9 tg mice on DHA diet compared to female tg mice on control diet. Immunoblot quantitation of the APOE receptor, LR11, which is involved in APP trafficking and A beta production, were unchanged in mice on DHA or control diets. Moreover drebrin levels were significantly increased in the hippocampus of tg mice on the DHA diet. Finally, in vitro DHA treatment prevented amyloid toxicity in cell cultures. Our findings support the concept that increased DHA consumption may play and important role in reducing brain insults in female AD patients.

Fate of tributyltin in a created tidal wetland.

The ability of Spartina alterniflora to degrade tributyltin (TBT) in contaminated dredge spoils was investigated in a created wetland at Little Creek Naval Amphibious Base in Norfolk, Virginia, USA. Concentrations of TBT up to 250 ng/g did not inhibit S. alterniflora growth over a 16-month period. Disappearance rates of TBT in vegetated and unvegetated treatments were similar, with half-lives of 300 to 330 d. Disappearance rates were not constant, but they were correlated to temperature changes and were possibly due to microbial degradation within the sediment. Of the initial amount of TBT in the sediment, only 0.4% accumulated in S. alterniflora biomass. Uptake of TBT by S. alterniflora was greatest in belowground biomass (43 ng/g). During plant senescence, most of the TBT was retained in the detrital material. Whereas S. alterniflora did not expedite the degradation of TBT, using TBT-contaminated dredge spoils to create wetlands is plausible. However, this should only be undertaken after further investigation into the potential for plant biomass to become a biovector for TBT.