bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vitamin D hypovitaminosis and efficacy of supplementation in spine surgery patients
Authors: Lindley Emily M. , Perry James , Patel Manishi , Noshchenko Andriy , Bond Amy , Burger Evalina L. , Cain Christopher M.J. , Patel Vikas V. 
Published: March 2019

Background:
Although there is evidence that hypovitaminosis D is present in many otherwise healthy adults, there is little information on supplementation in patients undergoing spine surgery. Thus, the purpose of this study was to determine the prevalence of preoperative hypovitaminosis D in spine surgery patients and evaluate the efficacy of postoperative vitamin D supplement regimens.

Methods:
Per standard of care, serum 25-hydroxyvitamin D levels were regularly drawn preoperatively and at 6 mo postoperatively; patients with hypovitaminosis D were prescribed a 3-month supplementation regimen based on their level of deficiency: 2000 IU/day, 50,000 IU/wk, or both 50,000 IU/wk and 2000 IU/day. For this analysis, we retrospectively reviewed charts of patients who had spine surgery to identify those with preoperative vitamin D levels. Rates of hypovitaminosis D were compared before and after treatment with supplementation.

Results:
Of 853 patients with preoperative serum vitamin D levels, 505 (59.2%) had hypovitaminosis D (<30 ng/mL). The rate of insufficiency (20-29 ng/mL) was 31.5%, and the rate of deficiency was 27.7%. At 6 mo postoperatively, the mean serum vitamin D level of patients with hypovitaminosis D increased from 19.7 ng/mL to 30.0 ng/mL (P<0.001). However, only 42.6% of patients achieved sufficiency at 6 mo. There were no differences in improvements between the supplementation regimens.

Conclusions:
Hypovitaminosis D is common among patients undergoing spine surgery. Patients should be tested preoperatively and prescribed a supplementation for at least 3 mo postoperatively. Serum levels should be checked regularly postoperatively, especially in deficient patients, to determine if further treatment is needed.
Are Serum Metal Ion Levels a Concern at Mid-term Followup of Revision Knee Arthroplasty With a Metal-on-metal Hinge Design?
Authors: Klasan Antonio , Meine Esko , Fuchs-Winkelmann Susanne , Efe Turgay , Boettner Friedrich , Heyse Thomas Jan 
Published: March 2019

Abstract

Background
Elevated serum levels of chromium and cobalt ions in metal-on-metal (MoM) bearing surfaces is a well-known phenomenon in THA. However, few studies have addressed this issue in complex primary and revision knee arthroplasty using a MoM hinged mechanism, and no study, to our knowledge, has investigated knees with MoM hinges in patients without megaprostheses (tumor prostheses).

Questions/purposes
We analyzed a series of patients who received MoM hinged revision knee prostheses and asked: (1) What are the serum metal ion levels at short-term followup? (2) Is there any correlation between metal ion levels and the Knee Society Score (KSS) at this followup?

Methods
Between 2013 and 2017, we performed 198 revision knee arthroplasties, of which 32 (17.7%) were performed with a latest-generation MoM hinge knee design. In addition, three complex primary TKAs utilizing the same design were included in this study. The device features a metal-on-polyethylene bearing with a MoM hinge. During that period, our general indications for using a hinge were single-stage and two-stage revision surgeries, revisions with large bone defects, and primary TKA with > 20° mechanical malalignment or collateral ligament insufficiency. Of the 35 patients who received this device, 23 patients (65% of the overall group who received this implant; 11 males, 12 females) were available for followup at a median of 28 months (range, 13-61 months), and the remaining 12 (35%) patients were lost to followup. Our rationale for reporting before the more typical 2-year minimum was the finding of elevated serum ion levels with unclear clinical significance. Median age at the time of surgery was 68 years (range, 52-84 years). None of the patients included in the study had other implants with MoM bearings. Serum ion levels of chromium (III) and cobalt were assessed using mass spectrometry. Ion levels > 5 ppb were considered elevated. Clinical outcome was assessed using the original KSS.

Results
Median chromium serum level was 6.3 ppb (range, 0.6–31.9 ppb) and median cobalt serum level was 10.5 (range, 1.0–47.5 ppb). Of the 23 patients, 16 had elevated serum ion levels. There was a moderate correlation between KSS and both chromium (p = 0.029, r = 0.445) and cobalt (p = 0.012, r = 0.502) levels.

Conclusions
Elevated metal ion levels and radiolucent lines are common after surgery with this MoM hinge design at short-term followup, and we believe this finding is of great concern. Although no patient has yet been revised, these patients will be closely monitored. We recommend that serum ion analysis become a routine part of followup after any hinge TKA in an attempt to better understand the potential consequences of this phenomenon.

Level of Evidence
Level IV, therapeutic study.
Polymethylmethacrylate Collagen Gel–Injectable Dermal Filler for Full Face Atrophic Acne Scar Correction
Authors: Joseph John H. , Shamban Ava , Eaton Laura , Lehman Alayne , Cohen Steven , Spencer James , Bruce Suzanne , Grimes Pearl , Tedaldi Ruth , Callender Valerie , Werschler Phillip 
Published: March 2019

BACKGROUND/OBJECTIVES
This trial evaluated the effectiveness and safety of Bellafill for full-face acne scar treatment.

PATIENTS AND METHODS
In this open-label, nonrandomized, multicenter pilot study investigating the use of polymethylmethacrylate for full-face atrophic acne scar correction, 42 adult subjects with a mean age of 43 years were treated and assessed for safety and effectiveness at Months 4 and 7. There were no hypersensitivity reactions to pretreatment skin testing or during scar treatments.

RESULTS
At 4 and 7 months after initial treatment, 92% and 95% of subjects, respectively, were responders with ≥1-point improvement on the 5-point Acne Scar Assessment Scale. Subjects reported very high levels of improvement on the Global Aesthetic Improvement Scale (GAIS), with 95% of subjects reporting “improved or better” at 4 months and 90% at 7 months. The outcome of the physician GAIS was also high with 92% of patients classified as “improved or better” at 4 months and 97% at 7 months. There were only 2 device-related adverse events, both mild events related to Bellafill skin test (bruising, ecchymosis). There were no serious adverse events in response to the treatment product in this short-term follow-up study.

CONCLUSION
Polymethylmethacrylate is effective for treating full-face acne scarring. Clinicaltrials.gov #NCT02642627.
Histologic Characterization of Polymethylmethacrylate Dermal Filler Biostimulatory Properties in Human Skin
Authors: Ronan Stephen J. , Eaton Laura , Lehman Alayne , Pilcher Brian , Erickson Christof P. 
Published: March 2019

BACKGROUND
Little literature exits on the mechanism of action of implanted polymethylmethacrylate (PMMA) filler.

OBJECTIVE
To characterize PMMA-induced dermal extracellular matrix production in the skin.

MATERIALS AND METHODS
Single-center, open-label prospective study in healthy volunteers undergoing removal of redundant skin was injected intradermally and subdermally with PMMA dermal filler (Bellafill). Punch biopsies were harvested over a time course and evaluated for the deposition of collagen-3 and procollagen-1, proteoglycans and elastin using immunohistochemistry. Blinded histopathologic readings were performed by a dermatopathologist to characterize the nature of the dermal extracellular matrix findings.

RESULTS
Normal inflammatory infiltrate was exhibited at all timepoints after PMMA injection with an influx of fibroblasts and new vasculature. Tissue proteoglycans were noted within the injectate beginning at Week 1 and persisted through the study end point. Increased collagen Type 3 was evident following the first week after injection, peaked at Month 2 and diminished through Months 3 through 6. Procollagen-1 was noted at Month 1 and continued to increase in intensity and organization through the study end point (6 months). Elastin staining was inconclusive. Polymethylmethacrylate microspheres remained within the initial injection area and became encapsulated within new collagen fibers. The growth and pattern of new connective tissue mimicked a normal wound healing response.

CONCLUSION
Polymethylmethacrylate-collagen gel filler stimulates collagen-3 and procollagen-1 when injected into human skin. This combination of neocollagenesis followed by microencapsulation of PMMA microspheres in the new tissue provides for long-lasting results.
Linear No-threshold (LNT) vs. Hormesis: Paradigms, Assumptions, and Mathematical Conventions that Bias the Conclusions in Favor of LNT and Against hormesis
Authors: Sacks Bill , Meyerson Gregory 
Published: March 2019

Abstract
The linear no-threshold assumption misunderstands the complex multiphasic biological response to ionizing radiation, focusing solely on the initial physical radiogenic damage. This misunderstanding is enabled (masked and amplified) by a number of mathematical approaches that bias results in favor of linear no-threshold and away from alternatives, like hormesis, that take biological response into account. Here we explore a number of these mathematical approaches in some detail, including the use of frequentist rather than Bayesian statistical rules and methods. We argue that a Bayesian approach cuts through an epidemiological stalemate, in part because it enables a better understanding of the concept of plausibility, which in turn properly rests on empirical evidence of actual physical and biological mechanisms. Misuse of the concept of plausibility has sometimes been used to justify the mathematically simple and convenient linearity-without-a-threshold assumption, in particular with the everywhere-positive slope that is central to linear no-threshold and its variants. Linear no-threshold’s dominance in the area of dose regulation further rests on a misapplication of the precautionary principle, which only holds when a putative caution has positive effects that outweigh the negative unintended consequences. In this case the negative consequences far outweigh the presumed hazards.
Factors Influencing Primary Care Follow-Up After Pediatric Mild Traumatic Brain Injury
Authors: Currie Dustin , Snedden Traci , Pierpoint Lauren , Comstock R. Dawn , Grubenhoff Joseph A. 
Published: March 2019

Objective:
To identify socioeconomic, demographic, and caregiver factors associated with children attending primary care provider (PCP) follow-up after emergency department (ED) evaluation for mild traumatic brain injury (mTBI).

Setting:
Pediatric trauma center ED.

Participants:
Children 8 to 18 years of age sustaining mTBI less than 48 hours prior to an ED visit. Mean age of the 183 participants was 12 years with no significant differences between those who attended follow-up and those who did not in race, ethnicity, insurance provider, or PCP office setting.

Design:
Thirty-day longitudinal cohort study.

Main Measures:
Insurance type, PCP practice setting, and a caregiver attitudes survey regarding mTBI recovery and management (5 questions each scored on a 5-point Likert scale). The primary outcome was attending a PCP follow-up visit within 1 month of injury.

Results:
Females were more likely than males to attend PCP follow-up (adjusted odds ratio: 2.27 [95% confidence interval: 1.00-5.18]). Increasing scores on the caregiver attitudes survey indicating greater concerns about recovery were significantly associated with attending PCP follow-up (adjusted odds ratio: 1.12 per unit increase in composite score [95% confidence interval: 1.02-1.23]). No other socioeconomic, demographic, or injury characteristics were associated with attending PCP follow-up.

Conclusions:
The ED counseling regarding PCP follow-up of mTBI should stress the importance of follow-up care to monitor recovery and identify presence of lingering symptoms.
Acceptance of Rehabilitation Technology in Adults With Moderate to Severe Traumatic Brain Injury, Their Caregivers, and Healthcare Professionals: A Systematic Review
Authors: Vaezipour Atiyeh , Whelan Brooke-Mai , Wall Kylie , Theodoros Deborah 
Published: March 2019

Background:
Moderate to severe traumatic brain injuries (TBIs) commonly result in persistent physical, cognitive, and/or emotional deficits that require long-term rehabilitation. Technology-enabled rehabilitation provides an innovative alternative to traditional intervention models. End-user acceptance of these interventions, however, is a critical factor in determining the effective implementation and acceptance of these technologies.

Objective:
To systematically review the literature to identify methods and measures used to evaluate user acceptance relating to rehabilitation technologies for adults with moderate to severe TBI, their caregivers, and healthcare professionals.

Methods:
Six key databases including Medline, Embase, CINAHL, Cochrane, Scopus, and Web of Science were searched using the relevant search terms.

Results:
From a yield of 2059 studies, 13 studies met the eligibility criteria. The review revealed limited research that formally evaluated user acceptance in relation to rehabilitation technologies designed for adults with TBI. Furthermore, where such evaluations were conducted, comprehensive research designs incorporating theoretical frameworks of technology acceptance were sparse. Importantly, a range of technologies and recommendations that positively influenced user acceptance were identified. Future directions for research in this area include the use of theory-driven research designs to enhance our understanding of technology acceptance, to support the development of rehabilitation technologies that maximize functional outcomes for individuals with TBI.
Limited Prediction of Performance Validity Using Embedded Validity Scales of the Neurobehavioral Symptom Inventory in an mTBI Veteran Sample
Authors: Menatti Andrew R. R. , Melinder Meredith R. D. , Warren Stacie L. 
Published: March 2019

Objective:
To test embedded symptom validity scales of the Neurobehavioral Symptom Inventory (NSI) as predictors of performance validity.

Setting:
A Veterans Affairs Level II TBI/Polytrauma outpatient care unit in the Midwestern United States.

Participants:
Veterans with a history of mild traumatic brain injury undergoing neuropsychological assessment as part of their routine care within the TBI/Polytrauma clinic.

Design:
Retrospective analysis of the existing clinical data.

Main Measures:
The NSI, the b Test, Test of Memory Malingering, Reliable Digit Span, California Verbal Learning Test-II Forced Choice.

Results:
Embedded NSI validity scales were positively correlated with number of performance validity test failures. Participants identified as invalid responders scored higher on embedded NSI validity scales than participants identified as valid responders. Using receiver operating characteristic analysis, the embedded NSI validity scales showed poor sensitivity and specificity for invalid responding using previously published cutoff scores. Only 1 scale differentiated valid from invalid responders better than chance.

Conclusion:
The embedded NSI validity scales' usefulness in predicting invalid neuropsychological performance validity was limited in this sample. Continued measurement of both symptom and performance validity in clinical settings involving traumatic brain injury treatment is recommended, as the present results support the existing research suggesting symptom validity tests and performance validity tests tap into related but ultimately distinct constructs.
Cognitive Reserve Protects Against Memory Decrements Associated With Neuropathology in Traumatic Brain Injury
Authors: Krch Denise , Frank Lea E. , Chiaravalloti Nancy D. , Vakil Eli , DeLuca John 
Published: March 2019

Objective:
To evaluate whether cognitive reserve (CR) moderates the relationship between neuropathology and cognitive outcomes after traumatic brain injury (TBI).

Setting:
Outpatient research organization.

Participants:
Patients with complicated mild (n = 8), moderate (n = 9), and severe (n = 44) TBI.

Design:
Prospective, cross-sectional study.

Main Measures:
Cognitive reserve was estimated using a test of word reading (Wechsler Test of Adult Reading). Diffusion tensor imaging (functional anisotropy) was used to quantify neuropathology. Neuropsychological test scores were submitted to principal components analyses to create cognitive composites for memory, attention, executive function, and processing speed domains.

Results:
At lower levels of neuropathology, people with higher CR exhibited better memory than those with lower CR. This benefit diminished as neuropathology increased and disappeared at the highest levels of neuropathology. Cognitive reserve ceased exerting a protective effect at premorbid intelligence levels below average.

Conclusion:
Cognitive reserve may differentially protect some cognitive domains against neuropathology relative to others. A clinical cutoff below which CR is no longer protective, together with a possible neuropathology ceiling effect, may be instructive for prognostication and clinical decision-making in cognitive rehabilitation.
Mobile Ecological Momentary Assessment of Postconcussion Symptoms and Recovery Outcomes
Authors: Sufrinko Alicia M. , Howie Erin K. , Charek Daniel B. , Elbin R. J. , Collins Michael W. , Kontos Anthony P. 
Published: March 2019

Objective:
Evaluate mobile ecological momentary assessment (mEMA) as an approach to measure sport-related concussion (SRC) symptoms, explore the relationships between clinical outcomes and mEMA, and determine whether mEMA was advantageous for predicting recovery outcomes compared to traditional symptom report.

Setting:
Outpatient concussion clinic.

Participants:
20 athletes aged 12 to 19 years with SRC.

Methods:
Prospective study of mEMA surveys assessing activity and symptoms delivered via mobile application (3 time blocks daily) and clinical assessment at visit 1 (<72 hours postinjury) and visit 2 (6-18 days postinjury). Linear mixed models examined changes in mEMA symptoms over time and relationships among simultaneous report of activity type (cognitive, physical, sedentary, vestibular) and symptoms. Linear regressions evaluated the association among symptoms for activity types and clinical outcomes.

Main Measures:
mEMA symptom scores, Post-Concussion Symptom Scale, neurocognitive testing, vestibular/oculomotor screening (VOMS).

Results:
mEMA response rate was 52.4% (N = 1155) for prompts and 50.4% per participant. Symptoms were lower in the morning (P < .001) compared with afternoon and evening. Higher mEMA symptoms were reported during vestibular compared with physical (P = .035) and sedentary (P = .001) activities. mEMA symptoms were positively associated with Post-Concussion Symptom Scale (PCSS) (P = .007), VOMS (P = 0.001-0.002), and recovery time (P < .001), but not neurocognitive scores. mEMA symptom score (P = .021) was a better predictor of recovery time than PCSS at either clinic visit.

Conclusion:
mEMA overcomes barriers of traditional symptom scales by eliminating retrospective bias and capturing fluctuations in symptoms by time of day and activity type, ultimately helping clinicians refine symptom management strategies.
CLINICOPATHOLOGIC CORRELATION OF GEOGRAPHIC ATROPHY SECONDARY TO AGE-RELATED MACULAR DEGENERATION
Authors: Li Miaoling , Dolz-Marco Rosa , Huisingh Carrie , Messinger Jeffrey D. , Feist Richard M. , Ferrara Daniela , Freund K. Bailey , Curcio Christine A. 
Published: March 2019

Purpose:
In an eye with geographic atrophy (GA) secondary to age-related macular degeneration, we correlated ex vivo histologic features with findings recorded in vivo using optical coherence tomography (OCT), near-infrared reflectance imaging, and fundus autofluorescence.

Methods:
In the left eye of an 86-year-old white woman, in vivo near-infrared reflectance and eye-tracked OCT B-scans at each of 6 clinic visits and a baseline fundus autofluorescence image were correlated with high-resolution histologic images of the preserved donor eye.

Results:
Clinical imaging showed a small parafoveal multilobular area of GA, subfoveal soft drusen, refractile drusen, hyperreflective lines near the Bruch membrane, subretinal drusenoid deposit (reticular pseudodrusen), and absence of hyperautofluorescent foci at the GA margin. By histology, soft drusen end-stages included avascular fibrosis with highly reflective cholesterol crystals. These accounted for hyperreflective lines near the Bruch membrane in OCT and plaques in near-infrared reflectance imaging. Subretinal drusenoid deposit was thick, continuous, extracellular, extensive outside the fovea, and associated with distinctive retinal pigment epithelium dysmorphia and photoreceptor degeneration. A hyporeflective wedge corresponded to ordered Henle fibers without cellular infiltration. The external limiting membrane descent, which delimits GA, was best visualized in high-quality OCT B-scans. Retinal pigment epithelium and photoreceptor changes at the external limiting membrane descent were consistent with our recent histologic survey of donor eyes.

Conclusion:
This case informs on the extent, topography, and lifecycle of extracellular deposits. High-quality OCT scans are required to reveal all tissue features relevant to age-related macular degeneration progression to GA, especially the external limiting membrane descent. Histologically validated signatures of structural OCT B-scans can serve as references for other imaging modalities.
SUTURELESS CLOSURE OF 23- AND 25-GAUGE LEAKING SCLEROTOMIES WITH THE SCLERAL NEEDLING TECHNIQUE
Authors: Felfeli Tina , Altomare Filiberto , Mandelcorn Efrem D. 
Published: March 2019

Purpose:
To describe and evaluate the efficacy of a novel technique, scleral needling (SN), for securing 23- and 25-gauge leaking sclerotomies in microincision vitrectomy surgery.

Methods:
A retrospective comparative review of consecutive cases of 23- and 25-gauge pars plana vitrectomy performed by a single vitreoretinal surgeon before the introduction of the SN technique (pre-SN; November 2016 to January 2017) and after the introduction of the SN technique (post-SN; November 2017 to January 2018) was conducted. The SN technique was implemented as an alternative to suturing, using a 30-gauge needle inserted perpendicularly through the full thickness of the sclera adjacent to the scleral opening, with the needle then immediately removed and sclerotomy closure confirmed.

Results:
A total of 203 eyes, 105 from pre-SN and 98 from post-SN, were included in the study. The number of eyes requiring suture closure was significantly reduced from 39% in the pre-SN group to 2% in the post-SN group (P < 0.001). The mean postoperative intraocular pressure and incidence of hypotony on Days 1 to 2, Days 3 to 20, and Days 21 to 50 was not significantly different between the pre-SN and post-SN groups. No major complications associated with the SN technique were noted during the study period.

Conclusion:
The SN technique is a safe and simple method for effectively securing leaking sclerotomies in microincision vitrectomy surgery.