title: Comparison of A-scan and MRI for the measurement of axial length in silicone oil-filled eyes.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  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.
authors.affiliation: University Department of Ophthalmology, University Hospital "Sestre milosrdnice", Vinogradska 29, Zagreb, Croatia. goranbencic@hotmail.com
authors.forename: G
authors.initials: G
authors.lastname: Bencic
authors.forename: Z
authors.initials: Z
authors.lastname: Vatavuk
authors.forename: M
authors.initials: M
authors.lastname: Marotti
authors.forename: V L
authors.initials: VL
authors.lastname: Loncar
authors.forename: I
authors.initials: I
authors.lastname: Petric
authors.forename: B
authors.initials: B
authors.lastname: Andrijevic-Derk
authors.forename: J
authors.initials: J
authors.lastname: Skunca
authors.forename: Z
authors.initials: Z
authors.lastname: Mandic
mesh_terms: D000368:Aged; D001699:Biometry / Q000379:methods; D005123:Eye / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification; D011446:Prospective Studies; D012030:Refractive Errors / Q000175:diagnosis* / Q000000981:diagnostic imaging; D012591:Scleral Buckling; D012827:Silicone Oils; D014463:Ultrasonography; D014821:Vitrectomy
chemical_list: D012827:Silicone Oils