An Experimental Model Exhibiting Anterograde and Retrograde Vascular Occlusion of Facial Fillers to Avoid Vision Loss.

Background: Facial filler injection techniques that help decrease the risk of vascular occlusion are an important growing area of study. This study demonstrates a model of injecting fillers into a simulated bifurcated arterial system, using different sized needle gauges at a constant injection pressure. Methods: Three facial fillers were injected into a bifurcated intravenous tubing with continuous irrigation at a constant pressure to simulate a vascular system. Videography was used to observe for retrograde flow through the simulated supratrochlear artery to the bifurcation point, where the filler was redirected by anterograde flow into the branch representing the ophthalmic artery. Results: Filler injection with retrograde flow to the bifurcation occurred with all the 27G needle trials. In comparison, the 30G needle trials were only able to reach the bifurcation point in three of the nine trials. The average time to the bifurcation point with subsequent ophthalmic artery anterograde flow with the 27G and 30G needles were 8.44 (95% confidence interval ±2.06) and 33.33 (95% confidence interval ±16.56) seconds, respectively. Conclusions: Larger 27G needles consistently reached retrograde flow and the bifurcation point faster than 30G needles. This study suggests thinner needles may be less likely to cause retrograde occlusion.

Relationship between 2-Hour Tacrolimus Concentrations and Clinical Outcomes in Long Term Kidney Transplantation.

Background: Tacrolimus is routinely monitored using trough concentrations, however, recent data have suggested that area under the curve (AUC) provides better correlation with toxicity and efficacy. Area under the curve is cumbersome to measure, but studies have demonstrated that surrogate time points such as 2-hour concentrations are well correlated with AUC. Methods: This is a single center, retrospective study of adult kidney transplant recipients with 2-hour tacrolimus concentrations measured over three years post-transplant. The primary outcome was to determine the difference in serum creatinine (Scr) in those with 2-hour tacrolimus concentrations greater than 20 ng/mL versus those less than or equal to 20 ng/mL. Results: A total of 150 kidney transplant recipients were included. The mean Scr and glomerular filtration rate were 1.49 ± 1.01 mg/dL and 59 ± 23.2 ml/min/1.73 m2, respectively, for the entire cohort. The rate of donor specific antibody formation was 2% and 8% experienced biopsy-proven rejection. The rate of cytomegalovirus viremia was 2% and BK viremia was 13%. There was no significant difference in kidney function over 36 months for the groups specified a priori. Conclusions: Long-term outcomes of maintaining tacrolimus 2-hour concentrations over 20 ng/mL is favorable with minimal opportunistic infections.