Abstract
Purpose :
To confirm and measure ultrasound-assisted enhanced delivery of gatifloxacin in mouse cornea, in vivo
Methods :
All the experiment was conducted with mouse corneas in both ex-vivo and in-vivo conditions. Total 15 mice were used in the experiment. Ultrasound treatment was performed on the mouse cornea by using an ultrasound transducer with 1MHz frequency for 5 minutes, and a gatifloxacin ophthalmic solution (Gatiflo) was instilled topically on the mouse cornea for 10 minutes. Gatifloxacin distribution in the mouse cornea was measured by two-photon microscopy (TPM) based on gatifloxacin intrinsic fluorescence. The maximum ultrasound intensity applicable to the cornea without damage was measured by treating the mouse cornea with various ultrasound intensities and examining cellular structure with TPM based on autofluorescence. Ultrasound assisted gatifloxacin delivery was measured by comparing gatifloxacin distribution in between ultrasound treated and untreated mouse corneas as controls with TPM. Temporal changes of gatifloxacin distribution in the mouse cornea were measured by time-lapse TPM imaging of the same cornea every 20 minutes for 1 hour in total.
Results :
The maximum applicable ultrasound intensity of the transducer, applicable for 5 minutes without damage, was measured to be 1.3W/cm2 in both ex-vivo and in-vivo mouse corneas. This ultrasound intensity was used in all the subsequent experiments. TPM imaging of gatifloxacin showed the increased gatifloxacin intensity in the ultrasound treated mouse cornea revealed as 36.9±4.2%, 95.1±22.4%, 387.7±22.8%, 178.7±6.0% compared to untreated controls at an time interval of 20 minutes for 1 hour. These values showed the longer maintenance of high gatifloxacin intensity in the epithelium of ultrasound treated mouse corneas compared to the untreated controls.
Conclusions :
Ultrasound assisted enhanced delivery of gatifloxacin into the mouse cornea and the longer maintenance of gatifloxacin in the corneal epithelium were experimentally confirmed, in vivo.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.