PURPOSE: The efficacy of two non-invasive tonometers, TonoLab and TonoPen XL, in detecting physiological or pharmacological changes of intraocular pressure (IOP) in mouse eyes, was assessed by comparison with a microneedle method. MATERIAL AND METHODS: C57BL6 mice, bred under the 12-hr light and dark cycle over 2 weeks, were used. Under systemic anesthesia, mouse eyes were cannulated by a microneedle connected to a transducer and a water reservoir. We manipulated the intracameral pressure by changing the reservoir height, and obtained tonometer readings at each pressure (n=39) with TonoLab and TonoPen XL. The correlation between each tonometer and the manometer was analyzed. Then the diurnal variation of IOP in the light and dark phases, and the IOP-lowering effect at 2 hr after latanoprost instillation, were measured with TonoLab, TonoPen XL, and a microneedle tonometer (n=8). RESULTS: In mouse eyes, TonoPen XL could not show reliable scores, but TonoLab readings showed a strong correlation with manometer readings (y=0.87x-0.27, r2=0.917). Nocturnal elevation of IOP in mouse eyes was significantly indicated with TonoLab and a microneedle tonometer (p<0.001), but not with TonoPen XL. Latanoprost significantly reduced IOP by 2.1+/-2.8 and 2.0+/-1.0 mmHg with TonoLab and a microneedle tonometer, but not with TonoPen XL. CONCLUSION: TonoLab provides similar readings to a microneedle tonometer, and diurnal variation and drug effect were detectable in mouse eyes. TonoLab promises to be a non-invasive and useful method to evaluate physiological and pharmacological studies in mouse eyes.
PURPOSE: The efficacy of two non-invasive tonometers, TonoLab and TonoPen XL, in detecting physiological or pharmacological changes of intraocular pressure (IOP) in mouse eyes, was assessed by comparison with a microneedle method. MATERIAL AND METHODS: C57BL6 mice, bred under the 12-hr light and dark cycle over 2 weeks, were used. Under systemic anesthesia, mouse eyes were cannulated by a microneedle connected to a transducer and a water reservoir. We manipulated the intracameral pressure by changing the reservoir height, and obtained tonometer readings at each pressure (n=39) with TonoLab and TonoPen XL. The correlation between each tonometer and the manometer was analyzed. Then the diurnal variation of IOP in the light and dark phases, and the IOP-lowering effect at 2 hr after latanoprost instillation, were measured with TonoLab, TonoPen XL, and a microneedle tonometer (n=8). RESULTS: In mouse eyes, TonoPen XL could not show reliable scores, but TonoLab readings showed a strong correlation with manometer readings (y=0.87x-0.27, r2=0.917). Nocturnal elevation of IOP in mouse eyes was significantly indicated with TonoLab and a microneedle tonometer (p<0.001), but not with TonoPen XL. Latanoprost significantly reduced IOP by 2.1+/-2.8 and 2.0+/-1.0 mmHg with TonoLab and a microneedle tonometer, but not with TonoPen XL. CONCLUSION: TonoLab provides similar readings to a microneedle tonometer, and diurnal variation and drug effect were detectable in mouse eyes. TonoLab promises to be a non-invasive and useful method to evaluate physiological and pharmacological studies in mouse eyes.
Authors: Mary E Pease; Frances E Cone; Scott Gelman; Janice L Son; Harry A Quigley Journal: Invest Ophthalmol Vis Sci Date: 2011-02-22 Impact factor: 4.799
Authors: Uttio Roy Chowdhury; Seung-Youn Jea; Dong-Jin Oh; Douglas J Rhee; Michael P Fautsch Journal: Invest Ophthalmol Vis Sci Date: 2011-08-16 Impact factor: 4.799
Authors: Kate E Keller; Janice A Vranka; Ramez I Haddadin; Min-Hyung Kang; Dong-Jin Oh; Douglas J Rhee; Yong-Feng Yang; Ying Ying Sun; Mary J Kelley; Ted S Acott Journal: Invest Ophthalmol Vis Sci Date: 2013-08-19 Impact factor: 4.799