Preliminary clinical evaluation of the treatment efficacy of a temperature-adjustable cryotherapy device for chronic, recurrent blepharitis in dogs.

Abstract

Objective: To preliminarily evaluate the treatment efficacy of a temperature-adjustable cryotherapy device for chronic, recurrent blepharitis in dogs.

Animals studied: Five dogs (eight eyes) of different breeds with blepharitis, which was unresponsive to systemic steroids.

Procedures: The dogs were subjected to ophthalmic examination, including Schirmer tear test-1 (STT-1), tear film break-up time (TFBUT) test, and slit-lamp biomicroscope examination. Cryotherapy was performed using a device featuring precise low-temperature control. A bandage lens and ointment (2% hypromellose) were applied before cryotherapy to protect the cornea. Carbon dioxide gas at 0°C was sprayed on the lesion for 10 s. In all patients, only topical antibiotics and corticosteroid were applied twice a day; systemic corticosteroids were not used. Pruritus and ocular discharge were scored based on the visual analog scale (VAS) before and 3 weeks after cryotherapy. Qualitative changes in tear film were measured using STT-1 and a TFBUT test. The effects on erythema and swelling were evaluated by ophthalmic examination.

Results: Pruritus improvement was confirmed in all eight eyes (five dogs). After cryotherapy, the average VAS score of pruritus significantly decreased from 4.12 ± 2.64 to 0.37 ± 0.51 (p < .001), and the average TFBUT significantly increased from 5.75 ± 4.80 to 13.75 ± 4.43 (p = .010). STT-1 and the VAS score of ocular discharge did not significantly differ. Erythema and swelling were improved in three out of eight eyes.

Conclusions: Cryotherapy is effective in treating blepharitis with pruritus and may become a new treatment option in patients in whom systemic corticosteroids are difficult to administer.