A Novel Trajectory of C7 Laminar Screws Determined Using Three-Dimensional Computed Tomography and Surgical Simulation Software: Comparison with a Pre-existing Trajectory

Methods@#Computed tomographic scans of a total of 50 male and 50 female patients were utilized. The placement of C7 laminar screws was activated employing the new and old trajectories. The success rate, the causes of failure, and the maximum allowable length of each trajectory were compared. @*Results@#Employing the new trajectory, the success rates of the unilaminar and bilaminar screws were 93% and 83%, respectively, which were significantly better than the old trajectory (80%, p<0.0001 and 70%, p=0.0003). The most prevalent cause of failure was laminar cortical breach followed by facet joint violation. The new trajectory also offered significantly longer maximum allowable screw length in unilaminar (32.5±4.3 mm vs. 26.5±2.6 mm, p<0.001), bilaminar cephalic (29.5±3.8 mm vs. 25.9±2.6 mm, p<0.0001) and bilaminar caudal (33.1±2.6 mm vs. 25.8±3.1 mm, p<0.001) screws than the old trajectory. With the new and old trajectories, 70% vs. 6% of unilaminar, 60% vs. 2% of bilaminar caudal, and 32% vs. 4% of bilaminar cephalic screws could be protracted perfectly into the corresponding lateral mass without any laminar cortical or facet joint violation (p<0.0001). @*Conclusions@#The novel trajectory possesses a substantially higher success rate, longer maximum allowable screw length, and higher chance to be extended into the lateral mass (a condition known as a lamino-lateral mass screw) than the old trajectory.

Research Models of the Nanoparticle-Mediated Drug Delivery across the Blood–Brain Barrier

Brain diseases and damages come in many forms such as neurodegenerative diseases, tumors, and stroke. Millions of people currently suffer from neurological diseases worldwide. While Challenges of current diagnosis and treatment for neurological diseases are the drug delivery to the central nervous system. The Blood–Brain Barrier (BBB) limits the drug from reaching the targeted site thus showing poor effects. Nanoparticles that have advantage of the assembly at the nanoscale of available biomaterials can provide a delivery platform with potential to raising brain levels of either imaging therapeutic drugs or imaging. Therefore, successful modeling of the BBB is another crucial factor for the development of nanodrugs. In this review, we analyze the in vitro and in vivo findings achieved in various models, and outlook future development of nanodrugs for the successful treatment of brain diseases and damages.

Volumetric Assessment of Fusion Mass and Its Clinical Correlations in Posterior Lumbar Interbody Fusion Depending on the Type of Bone Graft

Objectives@#This study was conducted to analyze associations between the volume of the fusion mass and clinical outcomes 1 year after posterior lumbar interbody fusion (PLIF).Summary of Literature Review: No study has investigated associations between the size of the fusion mass and clinical outcomes after PLIF. @*Materials and Methods@#The volume of the fusion mass and its clinical correlations after PLIF were analyzed in all patients and in subgroups. When a sufficient amount of local bone was available for grafting, only local bone without a graft extender was used (LbG group, n=20). If an inadequate amount of local bone was present for grafting, a local bone graft with porous hydroxyapatite bone chips was used (LbHa group, n=20). The same amount of demineralized bone matrix was used in both groups. The primary outcome was the relationship between the size of the fusion mass and clinical outcomes in all patients 1 year after surgery. The secondary outcome was a comparison of the size of the fusion mass and clinical outcomes by group. @*Results@#The volume of the fusion mass was not correlated with any clinical outcomes 1 year after surgery, either in the overall group of patients or in the subgroup analysis. @*Conclusions@#The volume of the interbody fusion mass was not related to any clinical outcomes 1 year after surgery. Furthermore, in cases with an insufficient amount of local bone for grafting, porous hydroxyapatite could be a relatively good alternative as a graft extender.

Efficacy of a Topical Gelatin-Thrombin Matrix Sealant in Reducing Postoperative Drainage Following Anterior Cervical Discectomy and Fusion

STUDY DESIGN: Retrospective fusion level(s)-, age-, and gender-matched analysis. PURPOSE: To determine whether the application of a topical gelatin-thrombin matrix sealant (Floseal) at the end of anterior cervical discectomy and fusion (ACDF) can reduce the amount of postoperative hemorrhage. OVERVIEW OF LITERATURE: The effect of the matrix sealant in decreasing postoperative hemorrhage following ACDF has not been reported. METHODS: Matrix sealant was (n=116, study group) or was not applied (n=58, control group) at the end of ACDF. Patients were selected by 1:2 matching criteria of fusion level(s), age, and gender. Seven parameters described below were compared between the two groups. RESULTS: The total drain amount for the first 24 hours (8+/-9 versus 27+/-22 mL), total drain amount until the 8-hour drainage decreased to < or =10 mL (8+/-10 versus 33+/-26 mL), and the total drain amount until 6 AM on the first postoperative day (7+/-8 versus 24+/-20 mL) were significantly lower in the study group than the control group (all p<0.001). The time for the 8-hour drainage to decrease to < or =10 mL was significantly lower in the study group (10+/-5 versus 26+/-14 hours, p<0.001). The 8-hour drainage decreased to < or =10 mL on the operation day in most patients (88%) in the study group versus mostly on the first (48%) or second (33%) postoperative day in the control group (p<0.001). The total drain amount until 6 AM on the first postoperative day was 0 mL in 43% of patients in the study group and in 7% in the control group (p<0.001). No patient in either group required hematoma evacuation. CONCLUSIONS: Application of the topical matrix sealant at the end of ACDF can significantly reduce the amount of postoperative hemorrhage.