An clinical and pharmacokinetic study for a drug delivery system (DDS) of gentamycin-loaded chitosan bar were carried out with the purpose to evaluate its efficacy and giving further data for its clinical applications. Eighteen cases of chronic osteomyelitis were treated by surgical necrectomy with implantation of gentamycin-load chitosan bar in the prepared bone cavity. After operation, the concentration of gentamycin in serum and wound drainage fluid were examined at different times and blood urea nitrogen (BUN) and serum creatinine (Cr) as well. The clinical results were evaluated by the conditions of wound healing and clinical and roentgenographic manifestations. The results showed that the serum gentamycin concentration reached its peak level (0.86 microgram/ml) at 24 hours after operation and lasted for 4 days. No increase in the concentrations of BUN and Cr were observed after implantation. The gentamycin concentration in wound drainage fluid was several hundred times higher than the minimum inhibitory concentration (MIC) for staphylococcus aureus. All of the 18 cases were followed up for 24.8 months (in an range of 6-34 months) 16 patients received initial cure and without any recurrence. So, it could be concluded that the gentamycin-loaded chitosan DDS was a simple and effective method for the treatment of chronic osteomylitis without the necessity to carry out a second operation to remove the drug carrier, and it was sound to popularize its clinical application.
In order to explore the histochemical changes in retina after intravitreal injection of gentamycin,a histochemical quantitative analysis of cytochrome oxidase(CYO)and acetylcholinesterase(ACHE)was performed with a computerized image analysis system and was compared with that of morphological study.The results showed that CYO decreased significantly in 100mu;g dosage group.With increasing intravitreal gentamycin dosage or observed days,CYO decreased gradually in all rabbits.In 100~500mu;g dosage groups,ACHE changed mildly at 3 days of injection.It decreased significantly at 7 days.However,it was destroyed completely in 1000~3000mu;g dosage groups at 3 days. （Chin J Ocul Fundus Dis,1994,10:232-235）