Glaucoma Watch prev next
Apr 12 2006
Neckties and IOP: The Controversy Continues
Clinicians have been aware of the increase of intraocular pressure from tight collars and neckties. A new study published in the Journal of Glaucoma, December 2005, by Talty and O’Brien gives us further information.
The age-matched study of 18 normal and 19 POAG patients randomly selected 1 eye for IOP measurement. Baseline IOP using Goldmann tonometry was established with open collar. IOP was taken 3 minutes after collar closed and necktie tightened. IOP was again taken at 12 minutes wearing time and 3 minutes after the tie was removed and collar opened.
The results indicated that a significant increase in IOP was noted only in the POAG subjects at the initial 3 minute IOP measurement. At the 12 minute measurement, there was a significant decrease in IOP in the POAG group but not in the normal group. Finally, after loosening the necktie for 3 minutes, there was a significant decrease in IOP among the normal group but not the POAG group.
Neither age nor collar size showed any significant correlation to change in mean IOP. The authors conclude that avoidance of extended tight neckties is not necessary in patients with open angle glaucoma.
Comments:
An important caveat to this study is that it is based on less than 20 patients in each category. Although there was a significant decrease in the IOP of the POAG group at the 12 minute measurement, the actual decrease observed in the POAG group was very close to that seen in the normal group (.94 mm vs .89 mm, respectively). Since this study involved a small sample size, the lack of statistical significance in the normal group given the close real measurements should be interpreted with caution.
Additionally, the authors do not comment on the significant decrease in IOP for the normal group once the necktie was loosened. Taken together, the data indicate that among the normal group, the IOP went up minimally at the first 3 minute measurement, then came down substantially at the next two measurements. Among the POAG group, the IOP went up significantly at the first measurement and then down significantly at the next measurement but does not appear to return to the baseline IOP within the timeframe of the study. This study contributes interesting evidence about the use of neckties in the glaucomatous population and warrants further investigation with a larger sample of patients.
