I read with interest the study by Tavakoli et al. (1) and found it to be interesting and useful in the management of diabetes for preventing further complications; however, I would like to make a few comments. In this study (1), whether patients with diabetes who had a previous history of corneal trauma, contact lens users, or those with cataract were excluded was not mentioned. These factors may alter corneal sensitivity.
In a previous study (2), it was seen that the noncontact corneal aesthesiometer was able to assess the corneal sensation threshold in an accurate and repeatable manner, and that the Cochet-Bonnet aesthesiometer has serious deficiencies in its design that limit its ability to accurately measure the corneal sensitivity at low-threshold stimulus. However, in the present study (1), the authors have found a good correlation between the Cochet-Bonnet aesthesiometer and the noncontact corneal aesthesiometer, and this appears to be very useful for daily practice. Confocal microscopy appears to allow early detection of beginning neuropathy, as decreases in nerve fiber bundle counts precede the impairment of corneal sensitivity (3).
The present study, along with confocal microscopy, will be useful for detecting neuropathy in diabetic patients, as well as in those with impaired glucose tolerance, so that an early intervention can be done to prevent further progression of complications.
