Toward global availability of low-cost, patient-specific cranial implants: creation and validation of automated CranialRebuild freeware application.

PURPOSE: Financial restrictions limit the options for hermetically precise, patient-specific cranial implants (PSCIs) after decompressive hemicraniectomy (DHC) in low-income countries. Use of image segmentation, modeling software, and 3D printers has lowered costs associated with PSCIs. However, requirements of time and technical expertise have prevented widespread utilization. Our objective was to create a fully automated software algorithm that is able to generate a virtual model (.STL) of a negative of an implant using CT imaging following DHC. METHODS: A freeware algorithm (CranialRebuild) was constructed with the following capabilities: (1) after the upload of digital imaging and communications in medicine files, the normal side is analyzed in reference to the side of DHC, (2) Boolean subtraction is used to obtain a virtual image of the desired implant, and (3) a two-piece virtual model (.STL) of the PSCI mold is generated. In four cadaveric specimens, a standard DHC was performed. Post-DHC CT imaging was used to obtain a .STL of the negative of the implant, which was then printed using poly-lactic acid (PLA). Methylmethacrylate cement was used to generate a PSCI from the mold. The PSCIs were implanted into the index specimens; cosmesis was subjectively evaluated using a 5-point Likert scale. RESULTS: Two specimens were graded as 4/5, indicating that minor post-processing modification was needed for optimal cosmesis. Two specimens were graded as 3/5, indicating that optimal cosmesis could be obtained following moderate post-processing modification. CONCLUSIONS: CranialRebuild can be used to create hermetically precise PSCIs at a fraction of the price of third-party vendors. Validation of this technology has significant implications for the accessibility of customized cranial implants worldwide.

Feasibility and Utility of a Flexible Outcome Assessment Battery for Longitudinal Traumatic Brain Injury Research: A TRACK-TBI Study.

The effects of traumatic brain injury (TBI) are difficult to measure in longitudinal cohort studies, because disparate pre-injury characteristics and injury mechanisms produce variable impairment profiles and recovery trajectories. In preparation for the Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) study, which followed patients with injuries ranging from uncomplicated mild TBI to coma, we designed a multi-dimensional Flexible outcome Assessment Battery (FAB). The FAB relies on a decision-making algorithm that assigns participants to a Comprehensive (CAB) or Abbreviated Assessment Battery (AAB) and guides test selection across all phases of recovery. To assess feasibility of the FAB, we calculated the proportion of participants followed at 2 weeks (2w) and at 3, 6, and 12 months (3m, 6m, 12m) post-injury who completed the FAB and received valid scores. We evaluated utility of the FAB by examining differences in 6m and 12m Glasgow Outcome Scale-Extended (GOSE) scores between participant subgroups derived from the FAB-enabled versus traditional approach to outcome assessment applied at 2w. Among participants followed at 2w (n = 2094), 3m (n = 1871), 6m (n = 1736), and 12m (n = 1607) post-injury, 95-99% received valid completion scores on the FAB, in full or in part, either in person or by telephone. Level of function assessed by the FAB-enabled approach at 2w was associated with 6m and 12m GOSE scores (proportional odds p < 0.001). These findings suggest that the participant classification methodology afforded by the FAB may enable more effective data collection to improve detection of natural history changes and TBI treatment effects.

Gender disparities in academic rank achievement in neurosurgery: a critical assessment.

OBJECTIVE: The objective of this study was to evaluate whether there are disparities in academic rank and promotion between men and women neurosurgeons. METHODS: The profiles of faculty members from 50 academic neurosurgery programs were reviewed to identify years in practice, number of PubMed-indexed publications, Doctor of Philosophy (PhD) attainment, and academic rank. The number of publications at each academic rank was compared between men and women after controlling for years in practice by using a negative binomial regression model. The relationship between gender and each academic rank was also determined after controlling for clustering at the institutional level, years in practice, and number of publications. RESULTS: Of 841 faculty members identified, 761 (90%) were men (p = 0.0001). Women represented 12% of the assistant and associate professors but only 4% of the full professors. Men and women did not differ in terms of the percentage holding a PhD, years in practice, or number of publications at any academic rank. After controlling for years in practice and clustering at the facility level, the authors found that men were twice as likely as women to be named full professor (OR 2.2, 95% CI 1.09-4.44, p = 0.03). However, when institution, years in practice, PhD attainment, h-index, and number of publications were considered, men and women were equally likely to attain full professorship (OR 0.9, 95% CI 0.42-1.93). CONCLUSIONS: Data analysis of the top neurosurgery programs suggests that although there are fewer women than men holding positions in academic neurosurgery, faculty rank attainment does not seem to be influenced by gender.

Concordance of common data elements for assessment of subjective cognitive complaints after mild-traumatic brain injury: a TRACK-TBI Pilot Study.

OBJECTIVE: To determine characteristics and concordance of subjective cognitive complaints (SCCs) 6 months following mild-traumatic brain injury (mTBI) as assessed by two different TBI common data elements (CDEs). RESEARCH DESIGN: The Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) Pilot Study was a prospective observational study that utilized the NIH TBI CDEs, Version 1.0. We examined variables associated with SCC, performance on objective cognitive tests (Wechsler Adult Intelligence Scale, California Verbal Learning Test, and Trail Making Tests A and B), and agreement on self-report of SCCs as assessed by the acute concussion evaluation (ACE) versus the Rivermead Post Concussion Symptoms Questionnaire (RPQ). RESULTS: In total, 68% of 227 participants endorsed SCCs at 6 months. Factors associated with SCC included less education, psychiatric history, and being assaulted. Compared to participants without SCC, those with SCC defined by RPQ performed significantly worse on all cognitive tests. There was moderate agreement between the two measures of SCCs (kappa = 0.567 to 0.680). CONCLUSION: We show that the symptom questionnaires ACE and RPQ show good, but not excellent, agreement for SCCs in an mTBI study population. Our results support the retention of RPQ as a basic CDE for mTBI research. ABBREVIATIONS: BSI-18: Brief Symptom Inventory; 18CDEs: common data elements; CT: computed tomography; CVLT: California Verbal Learning Test; ED: emergency department; GCS: Glasgow coma scale; LOC: loss of consciousnessm; TBI: mild-traumatic brain injury; PTA: post-traumatic amnesia; SCC: subjective cognitive complaints; TBI: traumatic brain injury; TRACK-TBI: Transforming Research and Clinical Knowledge in Traumatic Brain Injury; TMT: Trail Making Test; WAIS-PSI: Wechsler Adult Intelligence Scale, Fourth Edition, Processing Speed Index.

Safety and cost efficiency of a restrictive transfusion protocol in patients with traumatic brain injury.

OBJECTIVE Blood loss and moderate anemia are common in patients with traumatic brain injury (TBI). However, despite evidence of the ill effects and expense of the transfusion of packed red blood cells, restrictive transfusion practices have not been universally adopted for patients with TBI. At a Level I trauma center, the authors compared patients with TBI who were managed with a restrictive (target hemoglobin level > 7 g/dl) versus a liberal (target hemoglobin level > 10 g/dl) transfusion protocol. This study evaluated the safety and cost-efficiency of a hospital-wide change to a restrictive transfusion protocol. METHODS A retrospective analysis of patients with TBI who were admitted to the intensive care unit (ICU) between January 2011 and September 2015 was performed. Patients < 16 years of age and those who died within 24 hours of admission were excluded. Demographic data and injury characteristics were compared between groups. Multivariable regression analyses were used to assess hospital outcome measures and mortality rates. Estimates from an activity-based cost analysis model were used to detect changes in cost with transfusion protocol. RESULTS A total of 1565 patients with TBI admitted to the ICU were included in the study. Multivariable analysis showed that a restrictive transfusion strategy was associated with fewer days of fever (p = 0.01) and that patients who received a transfusion had a larger fever burden. ICU length of stay, ventilator days, incidence of lung injury, thromboembolic events, and mortality rates were not significantly different between transfusion protocol groups. A restrictive transfusion protocol saved approximately $115,000 annually in hospital direct and indirect costs. CONCLUSIONS To the authors' knowledge, this is the largest study to date to compare transfusion protocols in patients with TBI. The results demonstrate that a hospital-wide change to a restrictive transfusion protocol is safe and cost-effective in patients with TBI.