bluuebunny/crossref_metadata_2025 huggingface dataset:
Velocity modeling of supercritical pore fluids through porous media under reservoir conditions with applications for petroleum secondary migration and carbon sequestration plumes
Authors: Burke Lauri A.
Published: March 2022

Computational methods to characterize secondary migration in porous media traditionally rely on fluid transport equations with assumptions of time invariance, such as flow-path modeling of buoyancy vectors, statistical percolation algorithms, capillary pressure curves, or a form of Darcy’s law, which presumes instantaneous fluid transport. However, in petroleum systems modeling, the timeframe of secondary migration from source to reservoir is important to quantify in relation to other geologic factors, such as the timing of petroleum generation, fault movement, and seal formation. In addition, quantifying migration velocities enables an estimation of the distance a plume of geologically sequestered carbon dioxide travels over time, as well as the identification of low-permeability strata appropriate for long-term containment. This study introduces a method to quantify transport velocities of supercritical fluids in low-permeability lithologies for a broad range of rock and fluid properties likely encountered in the sedimentary sequence. A time-dependent form of Darcy’s law for pressure-driven viscous flow through homogeneous isotropic porous media was used to model flow velocities within a carrier bed. Thermodynamic equations of state were used to determine thermophysical properties of supercritical pore fluids under reservoir pressures ranging from 0 MPa to 200 MPa (0–29,000 psi) to constrain the momentum equations. Three case studies were examined that (1) estimated fluid flow velocities of methane within the low-permeability Upper Jurassic Haynesville Formation, (2) defined permeability-based flow units to evaluate saline formations for long-term geologic carbon sequestration, and (3) calculated the migration distance of carbon dioxide plumes at the Decatur, Illinois injection and sequestration project.
Quality of Life and its Determinants in Patients With Adrenal Insufficiency: A Survey Study at 3 Centers in the United States
Authors: Li Dingfeng , Brand Sarah , Hamidi Oksana , Westfall Ashleigh A , Suresh Malavika , Else Tobias , Vaidya Anand , Bancos Irina
Published: March 2022

Context

Current evidence on determinants of quality of life (QoL) in patients with adrenal insufficiency (AI) is limited.

Objective

This work aimed to identify the determinants of QoL in different subtypes of AI.

Methods

This multicenter cross-sectional survey study was conducted using a patient-centered questionnaire, the Short Form-36.

Results

Of 529 participants, 223 (42.2%) had primary AI, 190 (35.9%) had secondary AI, and 116 (21.9%) had glucocorticoid-induced AI. Median age was 58 years (interquartile range: 43-68 years) and 342 (64.8%) were women. In multivariable analyses, patients were more likely to report worse physical scores if they were women (odds ratio [OR]: 3.3; 95% CI, 1.8-6.0), had secondary AI or glucocorticoid-induced AI (OR: 2.5; 95% CI, 1.4-4.3), had shorter duration of AI (OR: 2.0; 95% CI, 1.1-3.6), were treated with more than 25 mg hydrocortisone equivalent daily (OR: 2.3; 95% CI, 1.2-4.6), had more comorbidities related to glucocorticoid excess (OR: 2.3; 95% CI, 1.3-4.0), reported a higher financial burden from AI (OR: 2.1; 95% CI, 1.3-3.6), and reported difficulties with AI management (OR: 2.5; 95% CI, 1.2-5.2). Women (OR: 2.1; 95% CI, 1.08-4.0), shorter duration of AI (OR: 2.4; 95% CI, 1.4-4.3), higher financial burden (OR: 2.3; 95% CI, 1.3-4.0), difficulties with AI management (OR: 2.6; 95% CI, 1.4-4.9), and lack of family support (OR: 9.1; 95% CI, 2.3-33.3) were associated with worse mental component scores.

Conclusion

In patients with AI, QoL could be improved by addressing certain determinants, such as avoiding GC overreplacement, providing in-depth education on self-management, offering more comprehensive insurance coverage, and ensuring better family support.
High Prevalence of Vertebral Fractures Associated With Preoperative GH Levels in Patients With Recent Diagnosis of Acromegaly
Authors: Frara Stefano , Melin Uygur Meliha , di Filippo Luigi , Doga Mauro , Losa Marco , Santoro Simona , Mortini Pietro , Giustina Andrea
Published: March 2022

Context

Osteopathy and morphometric vertebral fractures (VFs) are emerging complications in acromegaly. However, the prediction of VFs in this clinical setting is still a matter of uncertainty, and it is debated whether they are an early event in the natural history of the disease.

Objective

We aimed to evaluate the prevalence and determinants of morphometric VFs in patients with recently diagnosed acromegaly.

Methods

We enrolled 92 patients (43 men/49 women) on admission to the neurosurgery unit before transsphenoidal surgery, and compared them with control individuals without secondary forms of osteoporosis and pituitary disorders. We performed a VF assessment on preoperative chest x-ray images and collected biochemical, demographic, and clinical data.

Results

We detected a significantly higher prevalence of VFs (33.7%) in patients with acromegaly than in controls (P = .001). Among the patients with acromegaly and VFs, 12 (38.7%) showed multiple VFs, and 5 (16.1%) showed moderate/severe VFs. Patients with VFs had higher random serum growth hormone (GH) levels than those with no VFs (P = .03), but there was no difference in insulin-like growth factor-1 (IGF-1) (P = .07) and IGF-1/Upper Normal Limit ratio (P = .08). Free 3,5,3′-triiodothyronine was slightly lower in patients with acromegaly and VFs than in those without VFs (P = .05). In multiple logistic analysis, GH was independently associated with risk for VFs (P = .003). The preoperative serum GH cutoff value that predicted VFs was 12 ng/mL.

Conclusion

For the first time, high prevalence of radiological VFs is reported in patients with recent diagnosis of acromegaly. Therefore, we can hypothesize that VFs are an early phenomenon of acromegaly and related to GH levels. VF assessment should be included in the workup at the diagnosis of acromegaly.
Improving Agricultural Practices: Science and the Australian Sugarcane Grower, 1864–1915
Authors: Griggs Peter
Published: March 2022

Sugarcane emerged by 1884 as the most favored crop cultivated in the coastal lands of Eastern Australia between Cairns and Grafton. Initially, Australian canegrowers invested as little labor and capital as possible. Contemporary commentators, however, were very critical of the agricultural practices adopted by the country’s first canegrowers, noting a lack of careful cultivation and plowing, fertilizer use, drainage, and paddock design. Various reasons for the use of these "inadequate techniques" are discussed in this essay, with the conclusion being offered that the most important factor was a lack of scientific knowledge about farming under Australian conditions. By 1891 cane-growing techniques were reported to be "on the upgrade," with improved cane and sugar yields. Such a transformation had commenced due to the introduction of some mechanization and the dissemination of research findings and technical information about scientific cultivation methods under Australian conditions. This detail had been assembled during the 1890s and 1900s mainly by the Colonial Sugar Refining Company and the Queensland government Sugar Experiment Stations, which had been established following pressure from canegrowers who increasingly sought advice on the correct farming methods.
Red Gold of the Ozarks: The Rise and Decline of Tomato Canning, 1885–1955
Authors: Dicke Tom
Published: March 2022

Tomato growing and canning was an important part of Ozarks life for sixty years. For a few months every year, from before the start of the twentieth century until shortly after the end of World War II, tens of thousands of Ozarkers picked or processed a significant portion of the United States canned tomato pack. During most of these years, they processed millions of cases of canned tomatoes either on the farm or in small, family-owned and operated canneries. The social and economic environment of the area largely determined the rise and decline of canning in the Ozarks and the organization of the industry. It expanded rapidly, not because of any natural advantage in soil or climate, but rather because it fit well with the needs of small, and often poor, farmers raising a variety of crops. It peaked during the 1920s and 1930s and faded a generation later. Canning largely disappeared when changes to local life and work patterns, most notably the decline of small-scale mixed farming, altered the Ozarks in ways that made the area incompatible with small-scale canning.
Rural Police and the Defense of the Cattleman’s Empire in Texas and Alberta, 1875–1900
Authors: Graybill Andrew R.
Published: March 2022

During the cattle boom of the late nineteenth century, homesteaders at either end of the Great Plains raised livestock in conjunction with the cultivation of crops. In order to support their small herds of cattle, these individuals relied on unfettered access to grass and especially water, a resource in short supply on the semi-arid prairies of Texas and Alberta. Larger ranchers and cattle syndicates resented the challenge posed by the settlers and feared the competition for water and grass. Supported by officials in Austin and Ottawa--who favored rapid industrial development on the Plains--cattlemen seized control of the range by fencing pastures and water holes and evicting squatters. When homesteaders resisted this exclusion, government authorities dispatched their rural constabularies--the Texas Rangers and the North-West Mounted Police--to protect a closed but embattled range.
Selling Safety: The Farm Safety Movement’s Emergence and Evolution from 1940–1975
Authors: Oden Derek
Published: March 2022

This paper examines both the farm accident problem and the institutional response it engendered. Farm safety leaders fashioned a largely educational movement to address farm families’ technologically complex environments, since farming’s entrepreneurial nature required a different approach than did efforts in other occupational domains. The nation’s rural policymakers had largely neglected the issue until the Second World War, when they recognized that farm accidents threatened the nation’s wartime mobilization efforts. The farm safety movement was characterized by a cooperative effort, which included the National Safety Council, the United States Department of Agriculture, land grant colleges, and the nation’s rural youth organizations. However, efforts to impose more stringent regulations faced resistance from farmers after the creation of the Occupational Safety and Health Administration.
“The More They Listen, the More They Buy” Radio and the Modernizing of Rural America, 1930–1939
Authors: Craig Steve
Published: March 2022

Radio was one of several technologies that early twentieth-century reformers promoted as a means of modernizing and improving rural American life. Although the new medium was introduced in the 1920s, it was during the Depression decade of the 1930s that most rural families bought their first set. With the coming of radio, formerly isolated rural homes had access to world news, current weather and market reports, and a host of USDA-produced agricultural programs. However, it was the national network entertainment programs with their many advertisements that promised Depression-era rural listeners a better tomorrow in the form of a modernized urban consumer lifestyle. This article explores the coming of radio to rural areas during the 1930s and reviews some contemporary industry research findings on rural radio usage and consumer behavior.
The Changing Nature of Country Roads: Farmers, Reformers, and the Shifting Uses of Rural Space, 1880–1905
Authors: Wells Christopher W.
Published: March 2022

The period from the end of the Civil War to about 1905 saw some key changes in American country roads, including the passage of the first state-aid road laws, the creation of the first federal road agency, and the growth of a strong urban-rural coalition promoting rural road improvements. Although these have been well discussed, two significant but unrecognized changes lay at their heart. First, the effect of the good-roads campaigns of the 1890s in convincing farmers to embrace a major intellectual shift: trading the belief that roads were "natural"--local resources to be husbanded--for the idea that they were "technological"--publicly owned tools to be engineered in the service of social ends. Second, how the shifting uses of rural roads, from groups of urban cyclists touring the countryside to mail carriers delivering letters to farmhouses, not only strengthened the growing ties between rural and urban areas but also helped transform the basic political relationships between isolated communities and county, state, and national governments. Together these turn-of-the-century changes paved the way, literally and figuratively, for the growth of the extensive highway system that today is such a dominating characteristic of the American landscape.
Bandits, Mad Men, and Suicides: Fear, Anger, and Death in a Troubled Iowa Landscape, 1929–1933
Authors: Ossian Lisa L.
Published: March 2022

Iowa experienced two well-known incidents of rural violence in the early 1930s with the "Cow War of Cedar County" during 1931 and the Farmers’ Holiday Movement Strike in northwest Iowa in August 1932. However, the violence in rural Iowa from 1930 to 1933 became far more widespread, insidious, and personal than these two nationally covered mob incidents. The most extensive violence during the early Depression years involved hired hands and family members attacking and killing each other on scattered farmsteads, bandits robbing vulnerable country folk for their hidden money, gangsters stealing from small town banks, prohibition officers raiding rural stills, or farmers hanging themselves from barn rafters. The climate of financial fear, whether real of exaggerated, added to this overall morbid tension, and midwestern rural society no longer projected an idealistic image of strength, peace, and prosperity but rather one of fear and violence.
The Shelterbelt Project: Cooperative Conservation in 1930s America
Authors: Orth Joel
Published: March 2022

During the Shelterbelt Project of the 1930s, foresters trained and instilled with Progressive-era values confronted an uncooperative public and nature on the Great Plains. Foresters assumed planting trees in shelterbelts was primarily a scientific and technical task. However, they quickly compromised technical guidelines in the face of bureaucratic pressure and local desire. Foresters assumed compromise undermined technical success, but this was too simple an explanation. In some cases, such as the overuse of cottonwood, public pressure undermined long-term success, but in other cases, such as the narrowing of belt width, public pressure improved long-term prospects. Public unwillingness to engage in drawn-out and uncertain solutions and a bureaucratic refusal to open up the planning process consistently undermined the overall success of the project. Conservation planning in a democratic state is inherently multifaceted: political and social realities demand equal billing with technical ones, and natural and scientific uncertainties require that conservation planning be a process, rather than an immediate solution.
The Environmental Origins of Shifting Cultivation: Climate, Soils, and Disease in the Nineteenth-Century US South
Authors: Majewski John , Tchakerian Viken
Published: March 2022

Farmers and planters in the antebellum South held large tracts of unimproved land because they practiced shifting cultivation. Southern cultivators burned tracts of forest growth to quickly release nutrients into the soil. After five or six years, when the soil had been depleted, the old field was abandoned for as long as twenty years. Environmental factors such as poor soils, rugged topography, and livestock diseases accounted for the persistence of this practice, more so than slavery or the availability of western lands. Shifting cultivation slowly declined in the postbellum era, but southern farmers continued to improve a far smaller percentage of their land well into the twentieth century.
"No Responsibility and No Rice": The Rise and Fall of Agricultural Collectivization in Vietnam
Authors: Raymond Chad
Published: March 2022

Communist leaders in Vietnam attempted to use agricultural collectivization to transform a poor, agrarian country into a modern, socialist nation with an industrialized economy. Collectivized agricultural production lacked sufficient economic incentives for Vietnamese farmers; they preferred to produce privately for household consumption or the free market. State-initiated reforms to collectivize agriculture failed to improve the performance of the agricultural sector, and eventually the Vietnamese Communist Party was forced to abandon collectivization altogether. Once farmers were freed from collective labor and could pursue private production for the free market, Vietnam’s agricultural output skyrocketed.
"Esteeme a Little of Fish": Fish, Fishponds, and Farming in Eighteenth–Century New England and the Mid–Atlantic
Authors: Roberts Strother E.
Published: March 2022

Prior to the advent of scientific aquaculture in the mid-nineteenth century, English farming manuals of the seventeenth and eighteenth centuries instructed American colonists in the "art of husbandry," imparting advice and passing on the best-known strategies for keeping and rearing fish in enclosed ponds. The development of such ponds in the New England and Mid-Atlantic colonies during the eighteenth century marked the culmination of a long process by which British-American colonists adapted to declines in natural fish populations brought on by over-fishing and disruption of habitat by water-powered mills. The development of private fish-ponds as an increasingly important component of American mixed husbandry practices in long-settled areas by the end of the eighteenth century illustrates early American farmers’ ability to successfully adapt to self-wrought changes in their physical environment.
More a Plowshare than a Sword: The Legacy of US Cold War Agricultural Diplomacy
Authors: McGlade Jacqueline
Published: March 2022

Recently, agriculture has assumed an elevated role in world diplomacy due to pressing issues like international poverty relief, changing environmental conditions, farm trade imbalances, rising food prices, and the diversion of crops into bio-fuel production. Consequently, agricultural interests and production have become increasingly entwined with the politics of national protectionism and identity, domestic security, and preservation of trading advantage in developed and developing countries alike. This study examines the current impasse in world agricultural negotiations as an outgrowth of US foreign aid and trade policymaking as it evolved during the Cold War. In particular, it chronicles the historic shift in US foreign policy away from "give-away" food aid and surplus sales and toward the championing of global agricultural redevelopment under such programs as the Marshall Plan and PL 480, the Food for Peace program. As more a plowshare than a sword, the American Cold War push for worldwide agricultural modernization led many countries to experience new levels of food self-efficiency and export capabilities. Along with production parity, however, has come escalating levels of trade competition and national protectionism, which challenges again the achievement of world agricultural stability and prosperity.
Good for a National Cemetery: Questions of Land Use and an 1888 Botanical Expedition across Northern Michigan
Authors: JONES JOSEPH J.
Published: March 2022

In the second half of the nineteenth century, lumbermen logged the virgin pine forests of northern Michigan. The assumption was that the u plow would follow the axe, "and agriculture would dominate the region as it did in the southern half of the state. When farming did not quickly take root, William James Beai and Liberty Hyde Bailey led an expedition of scientists and journalists on a trip across northern Michigan in June 1888 to collect botanical samples, to find a site for a state forest reserve, and to recommend appropriate farming enterprises. This essay contends that without a key reforestation advocate in Charles Garfield the explorers focused too much on the questions related to botany and agriculture. While agriculture would ultimately thrive in some parts of the cutover, much of the region was unsuitable for intensive farming. The failure of the scientists to convey these limits adequately in newspaper articles and subsequent reports allowed for their work to be used by agricultural boosters throughout the region. The result was a cycle of erosion, fire, and farm abandonment that proved to be a political problem in Michigan for the first three decades of the twentieth century.
Colonial Foresters versus Agriculturalists: The Debate over Climate Change and Cocoa Production in the Gold Coast
Authors: HODGE JOSEPH M.
Published: March 2022

This article draws attention to the unfolding debate concerning forest cover loss, climatic change, and declining cocoa production in the Gold Coast (Colonial Ghana) during the early twentieth century. It argues that, although desiccationist theory was prevalent, its acceptance among colonial authorities in the Gold Coast was far from hegemonic. There were important dissenting colonial voices, particularly among agriculturalists, who argued that declining cocoa yields were due to plant diseases, most notably cocoa swollen shoot disease. It was based on the latter’s non-environmental model of disease transmission, rather than the premises of desiccation science, that the government’s postwar "cutting out campaign" of cocoa was predicated. Nevertheless, the foresters ’ correlation of the deterioration of cocoa areas with fears of desiccation was not without its effects on state practice, providing the rationale for an accelerated program of forest reservations in the 1930s.
The Hitherto Unknown: Toward a Theory of Synthetic Sound
Authors: Frank Hannah
Published: March 2022

In the 1920s and 1930s, filmmakers in Germany, the Soviet Union, and the United States created synthetic sounds by printing photographic or drawn patterns directly onto a filmstrip's optical soundtrack. This essay examines these practices alongside the radical film theories of Dziga Vertov and Jean Epstein in order to test the limits of sonic epistemology—and, ultimately, to imagine what it might mean to conceive of synthetic sound as documentary sound.
117 Identifying Patient Specific Variables Influencing Decisions to Perform Fusion in Grade I Spondylolisthesis Based on Expert Panel Recommendations from SLIP II Study
Authors: Schmidt Bradley T. , Parmar Vikas K. , Ghogawala Zoher , Resnick Daniel K.
Published: March 2022

INTRODUCTION:

The role of fusion as an adjunct to decompression in patients with stenosis associated with spondylolisthesis remains an area of controversy. We recently reported significant variation in treatment recommendations regarding fusion from an expert panel using data from the SLIP II study. We found that this variability was due to both surgeon specific and patient specific variables

METHODS:

A pilot study using de-identified data from the SLIP II study was performed. Expert panel recommendations were examined and patients whose recommendations reflected a consensus for decompression alone or decompression and fusion were identified. A consensus was defined as >80% agreement among panelists. Five patients were identified where there was >80% consensus for decompression alone and ten patients were identified where there was >80% consensus for decompression and fusion. Each of these 15 cases was then carefully examined to determine which characteristics (from the clinical vignette, imaging, and other patient collected data) most consistently differed between the two cohorts.

RESULTS:

With regard to demographic factors, the fusion cohort was younger (60 years vs 67.2 years, p = 0.077), and had a lower health state based on EQ-5D scores (0.50 vs 0.68, p = 0.04). There was no difference in the ODI between the cohorts (37.2 vs 37, p = 0.49).With regard to imaging characteristics, we found that greater degree of spondylolisthesis (24% vs 12%, p < 0.001), greater facet angle from horizontal (54 vs 48 degrees p = 0.12), and movement on dynamic images all predicted a recommendation for fusion.

CONCLUSION:

In examining the subset of patients with consensus from the expert panel regarding the utility of fusion, it is apparent that younger age, lower EQ-5D, sagittally-oriented facets, mobile spondylolisthesis, and degree of anterolisthesis were all associated with recommendation for fusion. This information provides significant evidence that particular patient characteristics drive senior surgeon decision making regarding the utility of fusion as an adjunct to decompression in this patient population. This has important policy implications and may help to explain disparate results from contemporary clinical trials.
118 Delayed Cranial Decompression Rates After Initiation of Unfractionated Heparin Versus Low-Molecular-Weight Heparin in Traumatic Brain Injury
Authors: Maragkos Georgios A. , Cho Logan , Legome Eric , Wedderburn Raymond , Margetis Konstantinos
Published: March 2022

INTRODUCTION:

Both unfractionated heparin (UH) and low-molecular weight heparin (LMWH) are routinely used prophylactically after traumatic brain injury (TBI) to prevent deep vein thrombosis. Their comparative risk for intracranial hemorrhage (ICH) development or worsening necessitating cranial decompression after prophylaxis initiation is unclear. Furthermore, the absence of a specific antidote for LMWH may lead to UH being used more often for high-risk patients.

METHODS:

We compared the incidence of delayed cranial decompression occurring after initiation of prophylactic UH vs. LMWH using the National Trauma Data Bank. Cranial decompression procedures included craniotomy, craniectomy, and external ventricular drain placement. Multiple imputation was utilized for missing data. To account for selection bias between UH and LMWH, we conducted propensity score matching using factors that were significantly different between the two groups. The matched UH and LMWH groups were then compared using logistic regression for the primary outcome of post-prophylaxis cranial decompression.

RESULTS:

A total of 218,594 TBI patients were included, with 61,998 (28.3%) receiving UH and 156,596 (71.7%) receiving LMWH as DVT prophylaxis. The UH group had significantly higher patient age, BMI, comorbidity rates, injury severity score, and worse motor Glasgow coma scale. After matching the UH and LMWH groups for these factors, logistic regression demonstrated lower rates of post-prophylaxis cranial decompression for the LMWH group (OR 0.13, 95% CI 0.11-0.16, P < 0.001).

CONCLUSION:

Despite the absence of a specific antidote, LMWH was associated with substantially lower rates of post-DVT-prophylaxis cranial decompression. This indicates that UH may not be the safer alternative in TBI patients at high risk for intracranial hemorrhagic complications.
134 Racial Disparities in Healthcare Resource Utilization After Pediatric Cervical and/or Thoracic Spinal Injuries: Is it Black and White?
Authors: Elsamadicy Aladine A. , Sandhu Mani , Freedman Isaac G. , Koo Andrew B. , Hengartner Astrid , Reeves Benjamin , Havlik John , Sarkozy Margot , Kundishora Adam , Tuason Dominick , DiLuna Michael
Published: March 2022

INTRODUCTION:

Racial disparities ubiquitously pervade the United States healthcare system. While there have been efforts to look at racial disparities in adult spinal trauma, there exists a paucity of data in pediatrics.

METHODS:

A retrospective cohort was performed using the 2017 admission year from 753 facilities. All pediatric patients (1-17 years) with cervical and/or thoracic spine injuries were identified using the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) diagnosis coding system. These patients were dichotomized by their race, either African American/Black or Caucasian/White. Demographic, comorbidiites, and injury presentations were collected. The total length of hospital stay, length of ICU stay, total days on ventilator, and hospital complications were also collected. A linear and logistic multivariate regression analysis was performed to determine the risk-ratio for hospital LOS as well as complication rate, respectively

RESULTS:

A total of 3,187 pediatric patients were identified, 637 were African-American (AA) and 2,550 were White (W). Compared to White patients, African-American cohort had a greater prevalence of cervical-only injuries (AA: 50.39% vs W: 37.18%, p < 0.001). While transport accident was most common injury etiology for both cohorts, African-American cohort had a greater prevalence of assault (AA: 18.05% vs W: 1.61%, p < 0.001) than White cohort. Overall complication rates were significantly higher among African-American patients (AA: 15.38% vs W: 9.33%, p < 0.001). Compared to their White counterparts, African-American patients had a 3.4 day longer mean hospital LOS (AA: 9.6 ± 21.55 days vs W: 6.23 ± 9.13 days, p < 0.001) and a 1.7 day longer mean ICU LOS (AA: 4.42 ± 9.98 days vs W: 2.69 ± 6.53 days, p < 0.001). African-American race was identified as a significant predictor of increased LOS on multivariate regression analysis [RR: 1.27, CI (0.52, 2.03), p < 0.001] but not hospital complications (p = 0.286).

CONCLUSION:

Our study demonstrates that race may have a significant impact on healthcare resource utilization following pediatric cervical and/or thoracic spinal trauma.
135 Natural History of Midline Brain Shift Following Hemispherectomy and its Association with Cerebral Spinal Fluid Diversion in Pediatric Epilepsy
Authors: Phillips H. Westley , Maniquis Cassia A. B. , Duby Shannon L. , Chen Jia-Shu , Bergeron David , Nagahama Yasunori , Ibrahim George , Weil Alexander G. , Fallah Aria
Published: March 2022

INTRODUCTION:

Hemispherectomy and its modern variants are effective surgical treatments for medically intractable unihemispheric epilepsy. While complications of hemispherectomy such as postoperative hydrocephalus are well documented, a less-studied phenomenon of postoperative midline brain shift (MLBS) has only been described anecdotally and never formally studied.

METHODS:

A retrospective review of consecutive pediatric patients who underwent hemispherectomy for medically refractory epilepsy at UCLA between 1994 and 2018 was performed. Patients were stratified by severity of MLBS, shunt placement, type of shunt valve, and opening pressure. MLBS progression was evaluated within groups using repeated measures ANOVA and compared between groups using ANCOVA while adjusting for follow-up time and baseline postoperative MLBS.

RESULTS:

In total, 97 patients with a median follow-up of 17.7 months were analyzed in this study. Of these patients, 27 (28%) required CSF diversion via shunt placement in the ipsilateral cavity for post-hemispherectomy hydrocephalus. In non-shunted patients, average MLBS immediately following hemispherectomy and at last follow-up was 4.8 ± 4.7 and 8.3±6.4 mm, respectively. In shunted patients, average MLBS immediately after hemispherectomy and at latest follow-up following shunt placement was 6.5 ± 3.3 and 14.6 ± 9.5 mm, respectively. MLBS increased for both shunted and non-shunted patients between first and last follow-up. However, MLBS progression between first and last follow-up was significantly greater in the shunted cohort than the non-shunted cohort [F (1,92) = 5.33, p = 0.023]. Placement of valves with higher opening pressure settings did not significantly increase MLBS relative to non-shunted patients [F (1,73) = 0.1, p = 0.765], whereas MLBS was significantly greater with low opening pressure settings [F (1,85) = 8.5, p = 0.004]. Furthermore, severe MLBS was significantly associated with debilitating headaches (p = 0.042).

CONCLUSION:

Patients undergoing hemispherectomy often develop postoperative MLBS. The progression of MLBS is significantly exacerbated by CSF shunting of the ipsilateral post-surgical cavity, specifically when accomplished with lower opening pressure settings. Severe MLBS is associated with severe headaches, suggesting that MLBS exacerbation may be related to overshunting.
136 Assessment of Peripheral Nerve Damage with a Myelin Specific MRI Method
Authors: Dortch Richard , Roth Alison , Murphy Rory
Published: March 2022

INTRODUCTION:

Management of peripheral nerve injuries relies on patient history/exam and electromyography. Unfortunately, the determination of a successful repair can take months to years using these methods, which delays decision-making and increases the likelihood of permanent sensorimotor deficits. Therefore, new biomarkers that monitor nerve de/regeneration prior to muscle reinnervation may allow for earlier detection of failed repairs, earlier reoperations, and improved restoration of function.

METHODS:

Peripheral nerve MRI was performed at 3 Tesla in 4 subjects (27-60 y.o., two female). Bilateral thigh/knee MRI was performed in two subjects with chronic traumatic neuropathies to the peroneal or sciatic nerves, and bilateral elbow MRI was performed in two subjects five months after posterior interosseous or ulnar nerve decompression. MTR maps were estimated from high-resolution magnetization transfer-weighted and proton density-weighted images. MTR values were estimated in (i) regions immediately distal to the site of damage, (ii) proximal regions in the same nerves, and (iii) healthy contralateral nerves. Damaged nerves (i) were compared to proximal/healthy nerves (ii, iii) using a Wilcoxon rank-sum test.

RESULTS:

MRI was well tolerated and free of motion and fat artifacts. Furthermore, nerves were readily distinguished from surrounding fat and muscle in the high-resolution MTR maps. MTR values were significantly reduced distal to the injury site (23.6 ± 3.6%) relative to proximal regions in the same nerves (33.9 ± 6.0%, p = 0.03) and healthy contralateral nerves (37.3±3.8%, p = 0.03).

CONCLUSION:

MTR detects decreases in myelin related to nerve damage and, therefore, may be a viable biomarker of Wallerian degeneration. Subject enrollment in a larger longitudinal study is ongoing, which will allow us to determine if MTR values are responsive to regeneration and predictive of outcomes. We are also investigating novel methods with improved specificity in the presence of edema, which may confound MTR acutely after trauma.
140 Social Determinants of Health: A Critical Factor in Adult Traumatic Brachial Plexus Injury Outcomes
Authors: Maasarani Samantha , Khalid Syed I. , Noland Shelley
Published: March 2022

INTRODUCTION:

Over the past three decades, there has been an accumulation of evidence pointing to social determinants of health (SDOH) as inherent causes for an array of health outcomes.

METHODS:

Between January 2010—June 2019, a retrospective analysis was performed using PearlDiver’s Mariner. One-to-one exact-matching based on baseline patient demographics was completed, creating three identical groups:

AT-BPI disparity cohort: patients with AT-BPI and presence of at least one SDOH disparity prior to injury:

• economic instability

• food insecurity

• inadequate education

• community and social context problems

• inaccessible healthcare facilities

• neighborhood and physical environment issues

AT-BPI without disparity cohort: patients with AT-BPI and the absence of any SDOH disparity. Control cohort: patients without AT-BPIs. The following primary psychosocial outcomes were included in our study: depression, anxiety, drug abuse, alcohol abuse, suicide attempt, post-traumatic stress disorder, and divorce.

RESULTS:

The matched population analyzed in this study consisted of 1,176 patients that were equally represented in the AT-BPI disparity cohort (n = 392, 33.33%), AT-BPI without disparity cohort (n = 392, 33.33%), and control cohort (n = 392, 33.33%). A total of 301 patients developed any psychosocial condition with four-years of their injury. Patients in the AT-BPI disparity cohort had significantly higher rates of developing any psychosocial condition (31.12%, p < 0.0005), depression (22.70%, p = 0.0032), anxiety (18.62%, p = 0.0203), drug abuse (7.91%, p = 0.0060), and alcohol abuse (4.85%, p = 0.03499) when compared to the other cohorts. Furthermore, the disparity cohort carried a significantly increased risk of developing any psychosocial condition (HR 1.42, 95% CI 1.09-1.86). The rates of suicide attempt, post-traumatic stress disorder, and divorce did not significantly differ between groups.

CONCLUSION:

AT-BPI patients with SDOH disparities are at increased risk of developing new-onset psychosocial conditions, such as depression, anxiety, drug abuse, and alcohol abuse. Clinicians should routinely screen for psychiatric conditions and assess social factors to improve identification of at-risk patients. A multidisciplinary approach incorporating medical, surgical, social, and psychological experts should be considered when managing these injuries.
142 Simultaneous Versus Staged Bilateral Carpal Tunnel Release Surgeries: A Retrospective Propensity-Matched Patient Comorbidity Analysis
Authors: Freedman Zachary , Daggubati Lekhaj C. , Rizk Elias B.
Published: March 2022

INTRODUCTION:

Carpal Tunnel Entrapment is the most common peripheral neuropathy, accounting for ∼ 90% of all neuropathies and frequently, occurs bilaterally. While thousands of carpal tunnel releases are performed each year bilaterally, the current understanding of pre-operative factors and postoperative outcomes in simultaneous and staged bilateral carpal tunnel release remain poor.

METHODS:

We performed a retrospective database analysis of the TriNetX database, consisting of 92 health care networks throughout the United States. Patients were divided into two cohorts: individuals with simultaneous bilateral carpal tunnel release and individuals with staged carpal tunnel releases within 3 months of each other. Numerous pre-operative comorbidities were evaluated for surgical determination and then, matched via propensity score matching. Post-operative outcomes were measured within 180 of surgery with and without propensity score matching. Statistical analysis was done through TriNetX software, which utilizes JAVA, R, and Python programming languages.

RESULTS:

The two cohorts result in 17,513 patients for staged carpal tunnel releases and 9,649 for simultaneous bilateral carpal tunnel release surgery. After propensity score matching, 9,289 patients were used in the analysis. Overall, those that underwent staged surgeries had more pre-operative co-morbidities (Hypertension, obesity, chronic kidney disease, arthritis, etc.). Upon matching, patients with staged releases had significantly higher postprocedural aftercare (OR 2.023; 1.813, 2.258), hand/ joint pain (OR 1.876; 1.212-2.905), pain in the extremity (OR 1.161; 1.055, 1.277), trigger finger (OR 1.608; 1.387-1.865), and an upper respiratory tract infection (OR 1.366; 1.206-1.546). Patients with simultaneous bilateral carpal tunnel release had more emergency room visits (OR .835; .766-.91). Non-significant outcomes pulmonary or venous embolism, intraoperative complications, hematomas, surgical site infection, and rehospitalizations.

CONCLUSION:

These findings demonstrate selection variance between simultaneous and staged carpal tunnel releases. Even after matching, simultaneous bilateral carpal tunnel releases provide fewer post-operative complications while only showing a mild increase in emergency room visits. Further prospective studies could be used to validate these results as well as provide new findings to the management and treatment of these groups.
143 Caudate and Dorsolateral Prefrontal Cortex Beta Power Plays an Important Role in Working Memory Updating
Authors: Qian Helen , Williams Ziv , Bick Sarah K. B.
Published: March 2022

INTRODUCTION:

Working memory, the short-term maintenance and manipulation of information in memory, plays a crucial role in both daily functioning and complex cognitive tasks. Working memory impairment is a prominent feature of multiple neurocognitive disorders. Previous imaging work has demonstrated that caudate and dorsolateral prefrontal cortex (DLPFC) exhibit significant activity during working memory updating and maintenance, and previous animal work has suggested that caudate beta power plays an important role in updating information held in DLPFC. A better understanding of the neurophysiology underlying working memory is needed to develop novel treatment strategies such as neuromodulation.

METHODS:

Eight subjects who underwent depth electrode placement for medically refractory epilepsy participated in our study. Subjects participated in an auditory working memory task in which they heard a set of three syllables and then were prompted to repeat the syllables in either the original or reverse order. We computed beta power and coherence in caudate and DLPFC electrodes during working memory updating.

RESULTS:

Both caudate and DLPFC showed a peak in beta power during updating of working memory, and beta power was significantly higher for correct trials during this peak period compared to both incorrect and control trials. Just prior to beta power increase during working memory updating, there was also an increase in beta coherence between caudate and DLPFC. Coherence during this interval was significantly greater for correct trials as well.

CONCLUSION:

Caudate and DLPFC beta power and connectivity are important for updating information held in working memory.
176 Changes in Brain and Spine Trauma Volume, Management, and Outcomes During the COVID-19 Pandemic in Kigali, Rwanda
Authors: Tang Oliver Y. , Uwamahoro Chantal , Marqués Catalina G. , Beeman Aly , Nshuti Steven , Jarmale Spandana , Aluisio Adam
Published: March 2022

INTRODUCTION:

During the COVID-19 pandemic, lockdown policies, movement restriction, and healthcare resource reallocation impacted traumatic brain injury (TBI) and spinal cord injury (SCI) incidence and treatment patterns. However, these trends have not been characterized in the Sub-Saharan Africa setting.

METHODS:

The study setting was Centre Hospitalier Universitaire de Kigali (CHUK), Rwanda’s national referral hospital. Adult injury patients presenting to the CHUK Emergency Department were prospectively enrolled from 1/27/20-6/28/20, excluding a cessation in research activities from March-May due to pandemic restrictions. Study personnel collected data on demographics, injury characteristics, treatments, and clinical outcomes. Differences in patients admitted before (1/27/20-3/22/20) and during (6/1/20-6/28/20) the COVID-19 pandemic were queried using chi-squared and Mann-Whitney tests.

RESULTS:

216 neurosurgical trauma patients at CHUK were included for analysis. 83.8% had TBI, 8.3% had SCI, and 7.9% had both TBI and SCI. The mean age was 34.1 (standard deviation = 12.5) and most patients were male (77.8%). Patients predominantly experienced injury following road traffic accident (65.7%). Weekly volumes for TBI (mean = 16.5 vs. 17.1, P = 0.819) and SCI (mean = 2.0 vs. 3.4, P = 0.086) did not change during the COVID-19 period. Patients during this period had lower Glasgow Coma Scale scores (mean = 13.8 vs. 14.3, P = 0.068) and Kampala Trauma Scores (mean = 14.0 vs. 14.3, P = 0.083) at admission, both denoting higher injury severity, but these differences did not reach significance. Patients admitted during the pandemic were significantly more likely to undergo brain CT imaging (65.7% vs. 50.0%, P = 0.030), with higher rates of documented hemorrhage, contusion, or fracture (35.7% vs. 19.2%, P = 0.008). Craniotomy rates also significantly increased during the pandemic (22.7% vs. 11.4%, P = 0.036). ED discharge (44.8% vs. 53.7%, P = 0.231) and mortality rates (2.9% vs. 4.9%, P = 0.505) did not change during this period.

CONCLUSION:

Neurosurgical trauma volume did not change significantly at CHUK during the COVID-19 pandemic, but presenting patients had higher injury severity and craniotomy rates. To the best of the authors’ knowledge, this is the first such TBI and SCI analysis conducted in Africa.
198 Use of GOLD Laser for the Endoscopic Treatment of Intracranial Cysts: Report of 25 Cases
Authors: Jimenez David F.
Published: March 2022

INTRODUCTION:

The GOLD Laser utilizes an active medium comprised of InGaAsP (Indium-Gallium III-Arsenide Phosphide) and the chemical element Au(gold). It is a solid-state laser that operates in the 980nm-1000nm infrared light spectrum using Wavelength Conversion Technology (TM).

METHODS:

A total of 25 patients presenting with intracranial cysts and elevated intracranial pressure were treated with a GOLD laser using endoscopic techniques. There were 19 intraventricular cysts and 6 middle fossa arachnoid cysts. There were 13 males and 12 females. Ages ranged between 19 days and 12 years with a mean of 14.15 years. In all cases the laser was used to fenestrate the cyst wall.

RESULTS:

The study period extended between February 2018 and May 2021. Surgical time ranged between 1.2 and 2.6 hours with a mean of 1.6 hours. There were no mortalities. There were no infections or complications. In all cases the cyst walls were able to be successful fenestrated. There were no recurrences or cyst reclosure requiring reoperation except for one patient who had multiloculated hydrocephalus secondary to gram negative infection. Total Joules used ranged between 912 and 2237 with a mean of 1779 J. The laser was set between 2 and 10 watts.

CONCLUSION:

The GOLD laser is an excellent tool for fenestrating loculated intracranial cysts successfully. Energy delivery from the laser allows for wall fulguration and permanently keeping the fenestration open and minimizing recurrences. There are no complications associated with its use. Excellent hemostasis and control of bleeding was achieved in all cases.