MATERIALS AND METHODS: AuNPs are synthesized by Q-switched Nd:YAG laser ablation technique. Cutaneous wound are induced on 45 Sprague Dawley rats on its dorsal part and then randomly divided into three groups. One group serves as non-treatment group (GC) and another two groups are subjected to AuNPs with and without PBMT. About 808 nm diode laser with output power of 100 mW is used as a light source for PBMT. The treatment was carried out daily with exposure duration of 50 seconds and total fluence of 5 J/cm2 . Wound area is monitored for 9 consecutive days using a digital camera, and histological examination is performed at 3rd, 6th, and 9th day through hematoxylin and eosin stain as well as Masson's trichrome stain.
RESULTS: The group of rats subjected to AuNPs with PBMT shows significantly accelerated wound closure compared to other groups. Histological results indicate that AuNPs and PBMT group is more effective in stimulating angiogenesis and triggers inflammatory response at early stage.
CONCLUSION: The application of AuNPs in PBMT has potential to accelerate wound healing due to enhanced epithelialization, collagen deposition and fast vascularization. Lasers Surg. Med. 49:380-386, 2017. © 2016 Wiley Periodicals, Inc.
PURPOSE: To evaluate the feasibility of percutaneous posterolateral fusion in the spine utilizing rhBMP-2.
STUDY DESIGN: Animal study.
METHODS: This is an animal research model involving 32 New Zealand white rabbits stratified into 4 study groups: control, autogenous iliac crest bone graft (ICBG), demineralized bone matrix (DBM), and rhBMP-2 groups, with 8 study subjects per group. The rhBMP-2 group was subdivided into the open technique (right side) and the percutaneous technique groups (left side). Fusion was graded at 6 weeks and 3 months after plain radiography, computed tomography, and clinical assessment with the following grading system: grade A, no bone formation; grade B, non-bridging bone formation; grade C, fusion; and grade D, fusion with ectopic bone formation.
RESULTS: No fusion was noted in the placebo and the DBM groups. However, in the DBM group, bone formation occurred in 37.5% of the subjects. The rhBMP-2 group had a higher fusion rate compared with the ICBG group at 6 weeks and 3 months. The fusion rate for the ICBG, the rhBMP-2 (open), and the rhBMP-2 (percutaneous) groups were 37.5%, 87.5%, and 50.0% at 6 weeks and 50.0%, 100.0%, and 62.5% at 3 months, respectively. Ectopic bone formation occurred in 12.5% of the cases in the rhBMP-2 (percutaneous) group and in 25.0% of the cases in the rhBMP-2 (open) group.
CONCLUSIONS: Usage of rhBMP-2 is feasible for percutaneous posterolateral fusion of the lumbar spine in this animal model. However, a more precise delivery system might improve the fusion rate when the percutaneous technique is used. A significant rate of ectopic bone formation occurred when rhBMP-2 was used.