Comparative estimation of anterior chamber depth and axial length by ultrasonography and orbscan ii

Abstract EN

Aim : to assess and compare the degree of agreement of anterior chamber depth (ACD) and axial length (AL) measurements by optical devices (Orbs can II) and contact ultrasound A-scan.

Patients and Methods : in this prospective study of 30 eyes of 25 consecutive patients, ACD and AL estimation were done by 2 methods—scanning slit topography (Orbs can II) and contact ultrasound A-scan.

One observer performed all Orbs can measurements and another performed all the ultrasonic measurements.

Repeated measures Analysis of Variance (ANOVA) was used to analyze difference between ACD and AL measurements by the 2 methods.

Difference in measurements between methods was assessed using the paired t test.

Results : the mean ACD (SD) by the 2 methods was 3.658 mm (0.254), and 3.406 mm (0.348), respectively.

There was a statistically significant difference between measurements recorded by the 2 methods (P >.01).

Mean contact A-scan measurements were 0.252 mm lower than by Orbs can II.

The mean AL were 24.220mm (0.851) and 23.897 (0.857) mm respectively.

There was none statistically significant difference between measurements recorded by the 2 methods (P >.01).

Mean contact A-scan measurements were 0.323 mm lower than by Orbs can II.

Conclusion : Application ultrasound gives consistently lower measurements for ACD-as well as the AL compared to Orbs can II.