ABSTRACT
Objectives: Research, knowledge, and technological advances have promoted minimally invasive image-guided diagnostic and therapeutic intervention. Such interventions are increasingly performed for musculoskeletal diseases by radiologists within outpatient settings. The objective of this study was to ascertain levels of safe practice among musculoskeletal radiologists in the United Kingdom and the Indian public health-care system, as defined by access to spinal surgeons and anesthetists during radiological spinal procedures. Material and Methods: An online cross-sectional survey of eight questions (multiple choice and free text) was circulated among musculoskeletal radiologists in the UK and India, to evaluate: (i) Image-guided practice among musculoskeletal radiologists. (ii) Types of interventions undertaken. (iii) Practice setting. (iv) Availability of supportive, backup access to spinal surgery services. Results: A total of 53 replies were received of which 43 (81.1%) were from musculoskeletal radiologists who perform spinal interventional procedures. Spinal biopsies and injections were the most common procedures performed by the 43 eligible radiologists (79.1% and 74.4%, respectively), with vertebroplasty and sacroplasty performed by only 16.3% and 11.6%, respectively. Less than half (46.5%) of musculoskeletal radiologists performing interventional procedures did so within a hospital setting with both a spinal surgeon and an anesthetist on site, 20.9% had an anesthetist on site but no spinal surgeon and 16.3% had neither on-site. Conclusion: Minimally invasive image-guided diagnostic and therapeutic intervention is a niche sub-specialty practiced by a few musculoskeletal radiologists. Enhanced resource allocation, skills training, and multidisciplinary service provision will ultimately minimize existing deficiencies, improving patient-related clinical outcomes, and quality of care.
ABSTRACT
OBJECTIVE: Poly(lactide-co-glycolide) (PLGA) nanoparticles are promising materials for the development of new drug-releasing systems. The purpose of this study was to evaluate the in vivo retention time of materials loaded in nanoparticles as compared with that of the material alone by in vivo imaging in nude mice. MATERIALS AND METHODS: Mice (n = 20) were injected with 0.1 mL fluorescent material 1,1′-dioctadecyl-3,3,3′,3′ tetramethylindotricarbocyanine iodide (DiR)-loaded PLGA nanoparticles (200 nm) into the right paraspinal muscle, and the same volume of pure DiR solution was injected into the left paraspinal muscle. Fluorescence images were obtained using an in vivo optical imaging system. Fluorescent images were taken 1 day after the injection, and seven more images were taken at 1-week intervals. Image analysis was done with ImageJ program, and one region of interest was chosen manually, which corresponded to the highest signal-intensity area of fluorescence signal intensity. RESULTS: After 7 weeks, 12 mice showed a right-sided dominant signal, representing the DiR loaded PLGA nanoparticles; 5 mice showed a left-side dominant signal, representing the free DiR solution; and 3 mice showed no signal at all beginning 1 day after the injection. During the 7-week period, the mean signal intensities of the free DiR solution and DiR-loaded PLGA nanoparticles diverged gradually. On day 1, the mean signal intensity of free DiR solution was significantly higher than that of DiR-loaded PLGA (p < 0.001). Finally, by week 7, DiR-loaded PLGA express significantly high signal intensity compared with free DiR solution (p = 0.031). CONCLUSION: The results of the current study suggested that therapeutic agents bound to PLGA nanoparticles may exhibit prolonged retention times.