To the Editor.
—In a recent tonometric study using either pressurized excised corneas attached to a Stepanik chamber or a nonspecified small number of enucleated human eyes, Moses and Grodzki (Archives 97:547-552, 1979) concluded that the Langham pneumatic tonometer is inaccurate for the measurement of intraocular pressure and "... is totally unsuited for tonography."Those conclusions, based on in vitro experiments, are in contradiction to the results and conclusions of numerous published studies on living eyes. This literature includes more than 30 articles dealing with the accuracy and applications of this tonometer, and more than 50 experimental and clinical reports in which the commercial instrument, the Alcon pneumatonograph (PTG), has been used in ophthalmic research studies on both animals and man. Therefore, the statements of Moses and Grodzki are of concern to the many ophthalmologists throughout the world who are using my tonometer. As the person principally responsible for its development,
Maurice E. Langham. Reliability and Application of the Pneumatonograph. Arch Ophthalmol. 1980;98(2):384–386. doi:10.1001/archopht.1980.01020030380029