PMID- 31618427
OWN - NLM
STAT- In-Data-Review
LR  - 20191023
IS  - 1552-5783 (Electronic)
IS  - 0146-0404 (Linking)
VI  - 60
IP  - 13
DP  - 2019 Oct 1
TI  - Changes in Corneal Detection Thresholds After Repeated Tear Film Instability.
PG  - 4234-4240
LID - 10.1167/iovs.19-27802 [doi]
AB  - Purpose: To use a human-based model to study the effects of repeated tear film
      instability on corneal detection thresholds to cold, mechanical, and chemical
      stimuli. Methods: Twenty-five subjects participated in three study visits. A
      computer-controlled Belmonte esthesiometer was used to estimate corneal detection
      thresholds to cold, mechanical, and chemical stimuli before, after, and 30
      minutes following 10 consecutive sustained tear exposure (STARE) trials. Subjects
      turned a pain knob (0-10) to indicate discomfort during STARE trials. The area of
      tear breakup and thinning in each trial was analyzed. Symptoms were evaluated by 
      the Current Symptom Questionnaire (CSQ). Results: There was a significant time
      effect on CSQ symptoms during both visits (Friedman test, P < 0.001), with
      immediately after repeated STARE and 30 minutes later significantly differing
      from before STARE (Wilcoxon, P < 0.017). Tear breakup occurred in every trial,
      ranging from 25% to 88% of the exposed corneal area and all subjects indicated
      discomfort during trials. There was a significant time effect on mechanical
      thresholds between before STARE mechanical thresholds and 30 minutes later
      (repeated measures analysis of variance [ANOVA] P < 0.001), but not cold (P =
      0.057) or chemical (P = 0. 565) thresholds. Conclusions: In this study, tear
      breakup during STARE trials was associated with discomfort, which when repeated, 
      resulted in increased symptoms of ocular discomfort and alterations of mechanical
      sensory thresholds after 30 minutes. These results suggest that tear film
      instability, which is thought to occur repeatedly during normal blinking among
      dry eye patients over the day, can produce neurosensory alterations.
FAU - Awisi-Gyau, Deborah
AU  - Awisi-Gyau D
AD  - Indiana University School of Optometry, Bloomington, Indiana, United States.
FAU - Begley, Carolyn G
AU  - Begley CG
AD  - Indiana University School of Optometry, Bloomington, Indiana, United States.
FAU - Situ, Ping
AU  - Situ P
AD  - Indiana University School of Optometry, Bloomington, Indiana, United States.
FAU - Simpson, Trefford L
AU  - Simpson TL
AD  - School of Optometry and Vision Science, University of Waterloo, Waterloo,
      Ontario, Canada.
LA  - eng
GR  - R01 EY021794/EY/NEI NIH HHS/United States
PT  - Journal Article
PL  - United States
TA  - Invest Ophthalmol Vis Sci
JT  - Investigative ophthalmology & visual science
JID - 7703701
SB  - IM
PMC - PMC6795343
EDAT- 2019/10/17 06:00
MHDA- 2019/10/17 06:00
CRDT- 2019/10/17 06:00
PHST- 2019/10/17 06:00 [entrez]
PHST- 2019/10/17 06:00 [pubmed]
PHST- 2019/10/17 06:00 [medline]
AID - 2753049 [pii]
AID - 10.1167/iovs.19-27802 [doi]
PST - ppublish
SO  - Invest Ophthalmol Vis Sci. 2019 Oct 1;60(13):4234-4240. doi:
      10.1167/iovs.19-27802.