Iontophoretic treatment of experimental pseudomonas keratitis in rabbit eyes using gentamicin-loaded hydrogels.
OBJECTIVE
To evaluate the efficacy of iontophoresis using a hydrogel probe containing gentamicin for the treatment of Pseudomonas keratitis in the rabbit cornea.


METHODS
Five groups (Groups 1-5) of 8 rabbits each were infected by injecting Pseudomonas aeruginosa into their corneas. Three dosings of corneal iontophoresis were performed, at intervals of 3.5 hours, using soft disposable gentamicin-loaded hydroxyethyl methacrylate hydrogel discs mounted on a portable iontophoretic device. Groups 1 and 2 were treated with corneal iontophoresis for 60 seconds and a current of 0.5 and 0.2 mA. Groups 3 and 4 were treated with hydrogel loaded with 0.9% NaCl solution, using a current of 0.2 mA and mock iontophoresis. Group 5 was treated with eye drops of 1.4% gentamicin every hour for 8 hours. One and a half hours after the last treatment, the animals were killed, and the corneas were excised and cultured for P. aeruginosa count after 24-hour incubation.


RESULTS
After iontophoretic treatment of gentamicin with a current of 0.5 mA (Group 1), the logarithmic value of Pseudomonas colony-forming units (CFUs) was 2.96 +/- 0.45. After lower current iontophoretic treatment (Group 2), the logarithmic Pseudomonas count was 5.25 +/- 0.54 CFUs. At the control groups (Groups 3-5), the Pseudomonas counts were found to be much higher, 7.62 +/- 0.28, 7.22 +/- 0.29, and 6.29 +/- 0.45 CFUs, respectively.


CONCLUSIONS
A short iontophoretic treatment using gentamicin-loaded hydrogels has potential clinical value in treating corneal infections.
Frucht-Pery
Joseph
J
Department of Ophthalmology, Hadassah University Hospital, Jerusalem, Israel. fruchtpery@md.huji.ac.il
Raiskup
Frederik
F
Mechoulam
Hadas
H
Shapiro
Mervyn
M
Eljarrat-Binstock
Esther
E
Domb
Abraham
A
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D016503:Drug Delivery Systems; D015818:Eye Infections, Bacterial / Q000188:drug therapy*; D005839:Gentamicins / Q000008:administration & dosage*; D020100:Hydrogels; D007478:Iontophoresis / Q000379:methods*; D007634:Keratitis / Q000188:drug therapy* / Q000382:microbiology; D008297:Male; D011552:Pseudomonas Infections / Q000188:drug therapy*; D011817:Rabbits
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D020100:Hydrogels