title: Pterygia measurements are more accurate with anterior segment optical coherence tomography - a pilot study.
abstract: BACKGROUND
  Slit-lamp beam measurements of a pterygium can be difficult to reproduce accurately.
  
  
  OBJECTIVE
  To compare standard slit-lamp beam measurements of pterygia to computer caliper measurements of Anterior Segment Optical Coherence Tomography (OCT)images.
  
  
  METHODS
  Thirteen pterygia often patients were evaluated. Two physicians independently measured each pterygium using the slit lamp beam. Caliper measurements of two different OCT images of each pterygium were obtained. All measurements determined the distance from the limbus to the pterygium apex.
  
  
  RESULTS
  The difference in the slit lamp beam measurements of each pterygium was calculated and the mean of the differences was 0.3 and the standard deviation was 0.32.The difference in the two OCT measurements of each pterygium was also calculated and the mean of the differences was 0.1 and the standard deviation was 0.12. A two-tailed t-test demonstrated a statistically significant difference in these measurements (p = 0.0256).
  
  
  CONCLUSIONS
  Anterior Segment Optical Coherence Tomography (OCT) gives significantly more reproducible results than the slit lamp beam for measurements of the distance of a pterygium's apex from the limbus. This tool may provide more accurate clinical assessment of extension of pterygia onto the cornea and may be useful for research purposes.
authors.affiliation: Department of Ophthalmology, Brooke Army Medical Center, San Antonio, TX, USA. mark.n.welch@gmail.com
authors.forename: M N
authors.initials: MN
authors.lastname: Welch
authors.forename: C D
authors.initials: CD
authors.lastname: Reilly
authors.forename: K
authors.initials: K
authors.lastname: Kalwerisky
authors.forename: A
authors.initials: A
authors.lastname: Johnson
authors.forename: S G
authors.initials: SG
authors.lastname: Waller
mesh_terms: D000869:Anterior Eye Segment / Q000473:pathology*; D003937:Diagnosis, Differential; D006801:Humans; D010865:Pilot Projects; D011625:Pterygium / Q000175:diagnosis*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D041623:Tomography, Optical Coherence / Q000379:methods*