Perioperative visual loss (POVL) accompanying nonocular surgery is a rare and potentially devastating complication but its frequency in commonly performed inpatient surgery is not well defined. We ...used the Nationwide Inpatient Sample to estimate the rate of POVL in the United States among the eight most common nonocular surgeries.
More than 5.6 million patients in the Nationwide Inpatient Sample who underwent principal procedures of knee arthroplasty, cholecystectomy, hip/femur surgical treatment, spinal fusion, appendectomy, colorectal resection, laminectomy without fusion, coronary artery bypass grafting, and cardiac valve procedures from 1996 to 2005 were included. Rates of POVL, defined as any discharge with an International Classification of Diseases, Ninth Revision, Clinical Modification code of ischemic optic neuropathy (ION), cortical blindness (CB), or retinal vascular occlusion (RVO), were estimated. Potential risk factors were assessed by univariate and multivariable analyses.
Cardiac and spinal fusion surgery had the highest rates of POVL. The national estimate in cardiac surgery was 8.64/10,000 and 3.09/10,000 in spinal fusion. By contrast, POVL after appendectomy was 0.12/10,000. Those undergoing cardiac surgery, spinal fusion, and orthopedic surgery had a significantly increased risk of developing ION, RVO, or CB. Patients younger than 18 yr had the highest risk for POVL, because of higher risk for CB, whereas those older than 50 yr were at greater risk of developing ION and RVO. Other significant positive predictors for some diagnoses of POVL were male gender, Charlson comorbidity index, anemia, and blood transfusion. There was no increased risk associated with hospital surgical volume. During the 10 yr from 1996 to 2005, there was an overall decrease in POVL in the procedures we studied.
The results confirm the clinical suspicion that the risk of POVL is higher in cardiac and spine fusion surgery and show for the first time a higher risk of this complication in patients undergoing lower extremity joint replacement surgery. The prevalence of POVL in the eight most commonly performed surgical operations in the United States has decreased between 1996 and 2005. Increased odds of POVL with male gender and comorbidity index indicate that some risk factors for POVL may not presently be modifiable. The conclusions of this study are limited by factors affecting data accuracy, such as lack of data on the intraoperative course and inability to confirm the diagnostic coding of any of the discharges in the database.
Every second year, the community experiment “Critical Assessment of Techniques for Structure Prediction” (CASP) is conducting an independent blind assessment of structure prediction methods, ...providing a framework for comparing the performance of different approaches and discussing the latest developments in the field. Yet, developers of automated computational modeling methods clearly benefit from more frequent evaluations based on larger sets of data. The “Continuous Automated Model EvaluatiOn (CAMEO)” platform complements the CASP experiment by conducting fully automated blind prediction assessments based on the weekly pre‐release of sequences of those structures, which are going to be published in the next release of the PDB Protein Data Bank. CAMEO publishes weekly benchmarking results based on models collected during a 4‐day prediction window, on average assessing ca. 100 targets during a time frame of 5 weeks. CAMEO benchmarking data is generated consistently for all participating methods at the same point in time, enabling developers to benchmark and cross‐validate their method's performance, and directly refer to the benchmarking results in publications. In order to facilitate server development and promote shorter release cycles, CAMEO sends weekly email with submission statistics and low performance warnings. Many participants of CASP have successfully employed CAMEO when preparing their methods for upcoming community experiments. CAMEO offers a variety of scores to allow benchmarking diverse aspects of structure prediction methods. By introducing new scoring schemes, CAMEO facilitates new development in areas of active research, for example, modeling quaternary structure, complexes, or ligand binding sites.
The Protein Model Portal (PMP) has been developed to foster effective use of 3D molecular models in biomedical research by providing convenient and comprehensive access to structural information for ...proteins. Both experimental structures and theoretical models for a given protein can be searched simultaneously and analyzed for structural variability. By providing a comprehensive view on structural information, PMP offers the opportunity to apply consistent assessment and validation criteria to the complete set of structural models available for proteins. PMP is an open project so that new methods developed by the community can contribute to PMP, for example, new modeling servers for creating homology models and model quality estimation servers for model validation. The accuracy of participating modeling servers is continuously evaluated by the Continuous Automated Model EvaluatiOn (CAMEO) project. The PMP offers a unique interface to visualize structural coverage of a protein combining both theoretical models and experimental structures, allowing straightforward assessment of the model quality and hence their utility. The portal is updated regularly and actively developed to include latest methods in the field of computational structural biology. Database URL: http://www.proteinmodelportal.org.
Retrospective cohort study.
(a) Compare operative variables, complications, and patient-reported outcomes (PROs) in patients with an upper instrumented vertebrae (UIV) of C2 versus C3/4, and (b) ...assess outcomes based on C2 screw type.
When performing elective posterior cervical laminectomy and fusion (PCLF), spine surgeons must choose the upper instrumented vertebrae (UIV) at the subaxial cervical spine (C3/4) versus C2. Differences in long-term complications and PROs remain unknown.
A single-institution, retrospective cohort study from a prospective registry was conducted. All patients undergoing elective, degenerative PCLF from December 2010 to June 2018 were included. Patients were divided into a UIV of C2 versus C3/4. Groups were 2:1 propensity matched for fusion extending to the thoracic spine. Demographics, operative, perioperative, complications, and 1-year PRO data were collected.
One hundred seventeen patients underwent elective PCLF and were successfully propensity matched (39 C2 vs. 78 C3/4). Groups were similar in fusion extending to the thoracic spine (P = 0.588). Expectedly, the C2 group had more levels fused (5.63 ± 1.89) compared with the C3/4 group (4.50 ± 0.91) (P = 0.001). The C2 group had significantly longer operative time (P < 0.001), yet no differences were seen in estimated blood loss (EBL) (P = 0.494) or length of stay (LOS) (P = 0.424). Both groups significantly improved all PROs at 1-year (EQ-5D; NRS-NP/AP; NDI). Both groups had the same percentage of surgical adverse events at 6.8% (P = 1.00). Between C2 screw type, no differences were seen in operative time, EBL, LOS, complications, or PROs.
In patients undergoing elective PCLF, those instrumented to C2 had only longer operative times compared with those stopping at C3/4. No differences were seen in EBL, LOS, 1-year PROs, and complications. Type of C2 screw had no impact on outcomes. Besides increased operative time, instrumenting to C2 had no detectable difference on surgical outcomes or adverse event rates.Level of Evidence: 3.
Intraocular pressure (IOP) increases in steep Trendelenburg positioning, but the magnitude of the increase has not been quantified. In addition, the factors contributing to this increase have not ...been studied in robot-assisted prostatectomy cases. In this study, we sought to quantify the changes in IOP and examine perioperative factors responsible for these changes while patients are in the steep Trendelenburg position during robotic prostatectomy.
In this prospective study, we measured IOP using a Tono-pen XL in 33 patients undergoing robot-assisted prostatectomy. The IOP was measured before anesthesia while supine and awake (baseline T1), anesthetized and supine (T2), anesthetized after insufflation of the abdomen with carbon dioxide (CO(2)) (T3), anesthetized in steep Trendelenburg (T4), anesthetized in steep Trendelenburg at the end of the procedure (T5), anesthetized supine before awakening (T6), and 1 hr after awakening in the supine position (T7).
On average, IOP was 13.3 +/- 0.58 (mean +/- SE) mm Hg higher at the end of the period of steep Trendelenburg position (T5) compared with supine position T1 (P < 0.0001). The least square estimates for each time point in mm Hg were as follows: T1 = 15.7, T2 = 10.7, T3 = 14.6, T4 = 25.2, T5 = 29.0, T6 = 22.2, T7 = 17.0. Using univariate mixed effects models for the T1-T5 time periods, peak airway pressure, mean arterial blood pressure, ETco(2), and time were significant predictors of the IOP increase, whereas age, body mass index, blood loss, volume of IV fluid administered, mean airway pressure, and desflurane concentration were not predictive. In T4-T5, which involved no significant positional or perioperative interventions, we performed a multivariate analysis to evaluate predictors of IOP increases. Surgical duration (in minutes) and ETco(2) were the only significant variables predicting changes in IOP during stable and prolonged Trendelenburg positioning. On average, IOP increased 0.21 mm Hg per mm Hg increase in ETco(2) after adjusting for time. An increase of 0.05 mm Hg in IOP per minute of surgery on average was observed during this period in the Trendelenburg position after adjusting for ETco(2).
IOP reached peak levels at the end of steep Trendelenburg position (T5), on average 13 mm Hg higher than the preanesthesia induction (T1) value. Surgical duration and ETco(2) were the only significant predictors of IOP increase in the Trendelenburg position (T4-T5).
BACKGROUND AND OBJECTIVES: Competition for neurosurgical residency training positions remains fierce. The support provided by applicants' home neurosurgery residency training programs (NRTP) is ...suspected to play a key role in the National Resident Matching Program (NRMP) process. We sought to evaluate the impact of the presence of an Accreditation Council for Graduate Medical Education–accredited NRTP at medical students' home institutions has on NRMP match outcomes. METHODS: Our cross-sectional observational study examined all US allopathic senior student Electronic Residency Application Service applications to a single NRTP from 2016 to 2022. RESULTS: We analyzed a total of 1650 Electronic Residency Application Service applications to a single NRTP, of which 1432 (86.8%) were from schools with an Accreditation Council for Graduate Medical Education–accredited NRTP (NRTP+) and 218 (13.2%) were from schools without a residency (NRTP−). NRTP+ applicants matched a higher rate on both pooled analysis (80.8% vs 71.6%, P = .002) and paired analysis ( P = .02) over the seven-cycle study period. This difference was present before (82.4% vs 73.9%, P = .01) and after (77.2% vs 65.6%, P = .046) the COVID-19 pandemic. Cohorts were overall similar; however, NRTP+ applicants had more publication experiences (19.6 ± 19.0 vs 13.1 ± 10.2, P < .001) and were more likely to complete a research gap year (RGY) (25.8% vs 17.0%, P = .004). Completing a RGY was associated with an increased likelihood of matching for NRTP+ applicants but not for NRTP− applicants: NRTP+: 84.9% vs 78.1% ( P = .0056); NRTP−: 70.3% vs 70.9% ( P = .94). CONCLUSION: The presence of a NRTP at a medical student's home institution is associated with improved NRMP match outcomes. This held true both before and after the COVID-19 pandemic. Applicants from schools with a NRTP had more publication experiences and were more likely to complete a RGY. Completion of a RGY is associated with an increased likelihood of matching only for students with an affiliated NRTP.
The Notch signaling cascade is an evolutionarily ancient system that allows cells to interact with their microenvironmental neighbors through direct cell-cell interactions, thereby directing a ...variety of developmental processes. Recent research is discovering that Notch signaling is also responsive to a broad variety of stimuli beyond cell-cell interactions, including: ECM composition, crosstalk with other signaling systems, shear stress, hypoxia, and hyperglycemia. Given this emerging understanding of Notch responsiveness to microenvironmental conditions, it appears that the classical view of Notch as a mechanism enabling cell-cell interactions, is only a part of a broader function to integrate microenvironmental cues. In this review, we summarize and discuss published data supporting the idea that the full function of Notch signaling is to serve as an integrator of microenvironmental signals thus allowing cells to sense and respond to a multitude of conditions around them.
•In addition to adjacent cells, Notch responds to a wide variety of microenvironmental signals.•Notch activation by microenvironmental signals might reflect the evolutionary origins of Notch.•The physiological importance of microenvironmental signal integration by Notch is not fully understood.
Spinal cord compression caused by spinal tumors is measured using the epidural spinal cord compression scale, also known as the Bilsky score. Whether Bilsky score predicts short-/long-term outcomes ...remains unknown. The objectives were to determine the correlation of Bilsky score 0-1 vs 2-3 with regards to (1) preoperative presentation, (2) perioperative variables, and (3) long-term outcomes.
A single-center, retrospective evaluation of a cohort of patients undergoing metastatic spine surgery was performed between 01/2010 and 01/2021. Multivariable logistic/linear/Cox regression were performed controlling for age, body mass index, race, total decompressed levels, tumor size, other organ metastases, and postoperative radiotherapy/chemotherapy.
Of 343 patients with extradural spinal metastasis, 92 (26.8%) were Bilsky 0-1 and 251 (73.2%) were Bilsky 2-3. Preoperatively, patients with Bilsky 2-3 lesions were older ( P = .008), presented more with sensory deficits ( P = .029), and had worse preoperative Karnofsky Performance Scale (KPS) ( P = .002). Perioperatively, Bilsky 2-3 patients had more decompressed levels ( P = .005) and transpedicular decompression ( P < .001), with similar operative time ( P = .071) and blood loss ( P = .502). Although not statistically significant, patients with Bilsky 2-3 had more intraoperative neuromonitoring changes ( P = .412). Although rates of complications ( P = .442) and neurological deficit ( P = .852) were similar between groups, patients with Bilsky 2-3 lesions had a longer length of stay ( P = .007) and were discharged home less frequently ( P < .001). No difference was found in 90-day readmissions ( P = .607) and reoperation ( P = .510) Long-term: LR ( P =.100) and time to LR (log-rank; P =0.532) were not significantly different between Bilsky 0-1 and Bilsky 2-3 lesions. However, patients with Bilsky 2-3 lesions had worse postoperative KPS ( P < .001), worse modified McCormick scale score ( P = .003), shorter overall survival (OS) (log-rank; P < .001), and worse survival at 1 year ( P = .012). Bilsky 2-3 lesions were associated with shorter OS on multivariable Cox regression (hazard ratio = 1.78, 95% CI = 1.27-2.49, P < .001), with no significant impact on time to LR (hazard ratio = 0.73, 95% CI = 0.37-1.44, P = .359).
Bilsky 2-3 lesions were associated with longer length of stay, more nonhome discharge, worse postoperative KPS/modified McCormick scale score, shorter OS, and reduced survival at 1 year. Higher-grade Bilsky score lesions appear to be at a higher risk for worse outcomes. Efforts should be made to identify metastatic spine patients before they reach the point of severe spinal cord compression..
Retrospective cohort.
In a cohort of patients undergoing adult spinal deformity (ASD) surgery, we used artificial intelligence to compare three models of preoperatively predicting radiographic ...proximal junction kyphosis (PJK) using: (1) traditional demographics and radiographic measurements, (2) raw preoperative scoliosis radiographs, and (3) raw preoperative thoracic magnetic resonance imaging (MRI).
Despite many proposed risk factors, PJK following ASD surgery remains difficult to predict.
A single-institution, retrospective cohort study was undertaken for patients undergoing ASD surgery from 2009 to 2021. PJK was defined as a sagittal Cobb angle of upper-instrumented vertebra (UIV) and UIV+2>10° and a postoperative change in UIV/UIV+2>10°. For model 1, a support vector machine was used to predict PJK within 2 years postoperatively using clinical and traditional sagittal/coronal radiographic variables and intended levels of instrumentation. Next, for model 2, a convolutional neural network (CNN) was trained on raw preoperative lateral and posterior-anterior scoliosis radiographs. Finally, for model 3, a CNN was trained on raw preoperative thoracic T1 MRIs.
A total of 191 patients underwent ASD surgery with at least 2-year follow-up and 89 (46.6%) developed radiographic PJK within 2 years. Model 1: Using clinical variables and traditional radiographic measurements, the model achieved a sensitivity: 57.2% and a specificity: 56.3%. Model 2: a CNN with raw scoliosis x-rays predicted PJK with a sensitivity: 68.2% and specificity: 58.3%. Model 3: a CNN with raw thoracic MRIs predicted PJK with average sensitivity: 73.1% and specificity: 79.5%. Finally, an attention map outlined the imaging features used by model 3 elucidated that soft tissue features predominated all true positive PJK predictions.
The use of raw MRIs in an artificial intelligence model improved the accuracy of PJK prediction compared with raw scoliosis radiographs and traditional clinical/radiographic measurements. The improved predictive accuracy using MRI may indicate that PJK is best predicted by soft tissue degeneration and muscle atrophy.
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