Article

Comparison of A-scan and MRI for the measurement of axial length in silicone oil-filled eyes.

University Department of Ophthalmology, University Hospital "Sestre milosrdnice", Vinogradska 29, Zagreb, Croatia.
The British journal of ophthalmology (impact factor: 2.92). 12/2008; 93(4):502-5. DOI:10.1136/bjo.2008.147868 pp.502-5
Source: PubMed

ABSTRACT The aim of the study was to compare the accuracy of A-scan biometry and MRI for the measurement of axial length in silicone oil-filled eyes.
This was a prospective randomised study of 70 patients. Biometry was performed using MRI in 33 patients (MRI group) and A-scan echography in 37 patients (A-scan group). The difference between predicted and final refraction was measured and evaluated statistically.
In patients with axial length >/=26 mm, the mean deviation of the final from predicted refraction was -1.23 (SD 0.67) D in the MRI group and -2.3 (SD 2.02) D in the A-scan group. The difference between these two groups was statistically significant (p = 0.02). In patients with axial length <26 mm, the mean deviation of the final from predicted refraction was -0.12 (SD 1.29) D in the MRI group and -0.33 (SD 1.39) D in the A-scan group. There was no statistical significance between the two groups (p = 0.629).
For highly myopic patients MRI biometry was a more accurate measurement of axial length in silicone oil-filled eyes. A-scan and MRI biometry were comparably accurate in measuring axial length in patients with axial length <26 mm.

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Keywords

33 patients
 
37 patients
 
70 patients
 
A-scan
 
A-scan biometry
 
A-scan echography
 
A-scan group
 
accurate measurement
 
axial length
 
axial length <26
 
final refraction
 
mean deviation
 
MRI biometry
 
MRI group
 
myopic patients MRI biometry
 
prospective randomised study
 
refraction
 
silicone oil-filled eyes
 
statistical significance
 
two groups