Kontiola A I, Goldblum D, Mittag T, Danias J
Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland.
Exp Eye Res. 2001 Dec;73(6):781-5. doi: 10.1006/exer.2001.1088.
Non-invasive intraocular pressure (IOP) measurement in rats can be performed with a variety of methods, none of which seems appropriate for scaling down for the mouse eye. In an attempt to develop such a method for non-invasive IOP measurement in mice, an alternative concept, that of rebound tonometry, was explored using an induction/impact (I/I) tonometer probe. IOP measurement using the rebound concept is based on bouncing a probe onto the eye and detecting its motion. Motion parameters of the probe, which vary according to eye pressure, are used to calculate the IOP. As a first step towards this goal a prototype I/I tonometer was evaluated for IOP measurement of the rat eye. Two similar instruments were constructed and tested for their ability to measure accurately and reliably rat IOP by comparing the measurements against the manometric (true) IOP as determined by cannulation ex vivo. Good correlation between the true IOP and the I/I measurements (R(2) = 0.95) was detected for IOP between 7.4 and 56 mmHg. Although individual eyes tested showed some variability in the relationship of the measured IOP with the true IOP, this variability was minimal. Starting probe-cornea distance between 3 and 5 mm, and angle of impact up to 25 degrees relative to the visual axis at the corneal apex, did not affect the reproducibility of the I/I tonometer. Comparison of I/I tonometer measurements to direct manometric determination of IOP by in vivo cannulation of eyes in anesthetized normal female Wistar rats correlated reasonably well (R(2) = 0.67) with manometrically determined IOP within the narrow range of normal rat IOPs (10-16.5 mmHg), underestimating the true (manometric) IOP by an average of 11.6%. The I/I tonometer is a reliable and accurate instrument for non-invasive IOP measurement in rat eyes that can potentially be adapted for IOP measurement in mice.
大鼠的非侵入性眼压（IOP）测量可以通过多种方法进行，但似乎没有一种方法适合缩小用于小鼠眼睛。为了开发一种用于小鼠非侵入性IOP测量的方法，探索了一种替代概念，即使用感应/冲击（I/I）眼压计探头的回弹眼压测量法。使用回弹概念进行IOP测量是基于将探头弹到眼睛上并检测其运动。探头的运动参数会根据眼压而变化，这些参数用于计算IOP。作为朝着这个目标迈出的第一步，对一种I/I眼压计原型进行了大鼠眼压测量评估。构建了两台类似的仪器，并通过将测量结果与通过离体插管确定的压力测量（真实）IOP进行比较，测试它们准确可靠地测量大鼠IOP的能力。在7.4至56 mmHg的眼压范围内，检测到真实IOP与I/I测量值之间具有良好的相关性（R(2) = 0.95）。尽管测试的单只眼睛在测量的IOP与真实IOP的关系上显示出一些变异性，但这种变异性很小。起始探头-角膜距离在3至5 mm之间，以及相对于角膜顶点视轴的冲击角度高达25度，均不影响I/I眼压计的可重复性。在麻醉的正常雌性Wistar大鼠中，将I/I眼压计测量结果与通过体内眼插管直接进行压力测量确定的IOP进行比较，在正常大鼠IOP的狭窄范围内（10 - 16.5 mmHg），与压力测量确定的IOP相关性较好（R(2) = 0.67），平均低估真实（压力测量）IOP 11.6%。I/I眼压计是一种用于大鼠眼睛非侵入性IOP测量的可靠且准确的仪器，有可能适用于小鼠的IOP测量。
