The Effects of Dry Eye on the Corneal Thickness Measured by Orbscan and Ultrasonic Pachymetry

Abstract

목적: Orbscan과 초음파로 측정한 각막두께 측정치에 건성안이 어떠한 영향을 끼치는지 알아보고자 한다.

대상과 방법: 30명의 환자, 60안을 대상으로 각각에 대해 Schirmer검사(점안마취후), 눈물 오스몰농도검사, Orbscan과 초음파 각막두께측정계 순으로 검사를 시행하였다. Schirmer검사상 10 ㎜/5분을 기준으로 건성안군과 대조군을 나누어 두 군간의 눈물

오스몰농도 및 Orbscan과 초음파 각막두께측정계로 측정한 중심각막두께의 평균을 비교하였다.

결과: 건성안군과 대조군은 각각 30안이었으며 눈물의 오스몰농도는 건성안군이 364.4±42.9 mOsm/ℓ이고 대조군이 337.8±34.5 mOsm/ℓ로 건성안군이 대조군에 비해 더 높았다(p=0.011). Orbscan으로 측정한 각막두께측정치는 건성안군이 547.5±27.3 ㎛로

대조군의 562.0±20.4 ㎛에 비해 더 얇았으나(p=0.023), 초음파로 측정한 측정치는 건성안군이 535.7±27.2 ㎛, 대조군이 547.6±20.1 ㎛로 유의한 차이를 보이지는 않았다(p=0.059).

결론: 건성안이 각막두께측정치에 미치는 영향은 Orbscan보다 초음파 각막두께측정계가 더 적을 것으로 생각되며, 건성안의 각막두께측정시 이를 염두에 두어야 할 것으로 생각된다.

Purpose: To evaluate the effect of dry eye on the corneal thickness measured by Orbscan and ultrasonic pachymetry.

Methods: The central corneal thickness was measured by both ultrasonic and Orbscan pachymetry in 30 eyes with dry eye (dry eye group) and in 30 eyes of normal subjects (control group). Dry eye was diagnosed when a Schirmer test result was

less

than 10 ㎜ (after topical anesthesia) and the test for tear osmolarity was also performed.

Results: Tear osmolarity was 364.4±42.9 mOsm/ℓ in dry eye group and 337.8±34.5 mOsm/ℓ in control group. It was significantly higher in dry eye group than in the control group (p=0.011). Mean central corneal thickness measured by

Orbscan

pachymetry was 547.5±27.3 ㎛ in dry eye group and 562.0±20.4 ㎛ in the control group. It was significantly thinner in dry eye group than in the control group (p=0.023). Mean central corneal thickness measured by ultrasonic pachymetry was

535.7±27.2

㎛ in dry eye group and 547.6±20.1 ㎛ in the control group with out significant difference between the two groups (p=0.059).

Conclusions: The corneal thickness measured by ultrasonic pachymetry is less affected by dry eye compared to that measured by Orbscan pachymetry.