title: Immersion B-guided versus contact A-mode biometry for accurate measurement of axial length and intraocular lens power calculation in siliconized eyes.
abstract: OBJECTIVE
  To compare the accuracy of the immersion B-guided versus the contact A-mode biometry in measuring the axial length and intraocular lens power of the siliconized eyes.
  
  
  METHODS
  Sixty eyes with silicone cataract were divided into two groups. In Group A, the axial length of 30 eyes was measured by contact A-mode biometry. In Group B, the axial length of 30 eyes was measured by immersion B-guided biometry. The postoperative refraction was done after 3 months and was compared with the attempted values.
  
  
  RESULTS
  Twenty-five eyes of the B-guided group (83.3%) achieved a refraction deviation of ± 1 D or less versus 14 (46.6%) in the A-mode group. The mean refractive deviation was less with the B-mode (0.15 ± 0.94) versus contact A-mode (-0.95 ± 1.157); the difference is statistically significant (P = 0.024, Fisher test).
  
  
  CONCLUSIONS
  B-guided biometry was found to be more accurate than the contact method in measuring axial length and intraocular lens power calculation in siliconized eyes and spared the time and cost needed for a separate B-scan.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, Cairo University, Cairo, Egypt. khaledabueleinen@yahoo.com
authors.forename: Khaled G
authors.initials: KG
authors.lastname: Abu El Einen
authors.forename: Mervat H
authors.initials: MH
authors.lastname: Shalaby
authors.forename: Hoda T
authors.initials: HT
authors.lastname: El Shiwy
mesh_terms: D058452:Axial Length, Eye / Q000000981:diagnostic imaging*; D001699:Biometry / Q000295:instrumentation / Q000379:methods*; D002386:Cataract / Q000139:chemically induced*; D002387:Cataract Extraction; D006801:Humans; D019654:Lens Implantation, Intraocular; D007908:Lens, Crystalline / Q000187:drug effects*; D007910:Lenses, Intraocular; D055095:Optics and Photonics; D012008:Recurrence; D012029:Refraction, Ocular / Q000502:physiology; D012163:Retinal Detachment / Q000601:surgery; D012827:Silicone Oils / Q000008:administration & dosage / Q000009:adverse effects*; D014463:Ultrasonography; D014792:Visual Acuity / Q000502:physiology; D014821:Vitrectomy
chemical_list: D012827:Silicone Oils