Related Experiment Videos
Effects of subconjunctival injection of mitomycin-C on iridial circulation in rabbits
A Tomidokoro1, M Araie, Y Tamaki
1Omiya Red Cross Hospital Eye Clinic Japan Saitama, 338-8553,
Purpose:
To determine the effects of a subconjunctival injection of mitomycin-C (MMC) on iridial circulation in rabbits.
Methods:
Dutch rabbits anesthetized with pentobarbital received a 0.2-ml subconjunctival injection of 0.4 mg/ml or 0.1 mg/ml MMC; the contralateral eye received 0.2 ml physiological saline. Intraocular pressure (IOP) and NB( iris), a quantitative index of iridial tissue blood velocity, were measured up to 24 hours after treatment.
Results:
At a dosage of 0.4 mg/ml MMC, NB iris obtained from the iridial area adjacent to the injection site decreased significantly by 13.6% and 18.6% at 1 and 2 hours (P = 0.03, 0.01, respectively) after treatment; NB iris obtained on the contralateral side of the injection showed no significant change. In eyes treated with 0.1 mg/ml MMC, NB iris did not change significantly. The mean IOP was significantly lower by 3.1, 3.0, and 1.8 mm Hg at 6, 12, and 24 hours after the 0.4 mg/ml injection of MMC compared with the fellow eyes (P = 0.03, 0.01, and 0.03, respectively), the IOP decreased by 1.7 mm Hg at 4 hours in the eyes treated with 0.1 mg/ml MMC (P = 0. 04).
Conclusions:
Subconjunctival injections of 0.2 ml of 0.4 mg/ ml MMC caused not only a significant decrease of IOP but also a transient but significant effect on iridial circulation.
Insights
Subconjunctival injections of mitomycin-C (MMC) in rabbits significantly reduced intraocular pressure (IOP) and temporarily affected iridial blood flow. Higher MMC concentrations showed more pronounced effects on circulation.
Area of Science:
- Ophthalmology
- Pharmacology
- Veterinary Medicine
Background:
- Subconjunctival injections are used in ophthalmic procedures.
- Mitomycin-C (MMC) is an antimetabolite with potential effects on ocular tissues.
- Understanding MMC's impact on ocular circulation is crucial for its safe application.
Purpose of the Study:
- To investigate the effects of subconjunctival mitomycin-C (MMC) on iridial blood flow and intraocular pressure (IOP) in a rabbit model.
Main Methods:
- Dutch rabbits received subconjunctival injections of MMC (0.4 mg/ml or 0.1 mg/ml) or saline.
- Intraocular pressure (IOP) and iridial tissue blood velocity (NB iris) were measured up to 24 hours post-injection.
Main Results:
- The 0.4 mg/ml MMC dose significantly decreased iridial blood velocity adjacent to the injection site at 1 and 2 hours.
- No significant changes in iridial blood velocity were observed on the contralateral side or with the 0.1 mg/ml MMC dose.
- A significant reduction in IOP was observed at 6, 12, and 24 hours after the 0.4 mg/ml MMC injection, and at 4 hours with the 0.1 mg/ml dose.
Conclusions:
- Subconjunctival injections of 0.4 mg/ml MMC lead to a significant decrease in IOP.
- These injections also cause a transient, significant reduction in iridial circulation.
- The findings highlight the circulatory effects of subconjunctival MMC, necessitating careful consideration in ophthalmic treatments.