NR ACHV
AU Cass,K.; Thompson,C.M.; Tromans,C.; Wood,I.C.J.
TI Evaluation of the validity and reliability of A-scan ultrasound biometry with a single use disposable cover
QU The British Journal of Ophthalmology 2002 Mar; 86(3): 344-9
PT journal article
AB BACKGROUND: The UK Medical Devices Agency has suggested that ophthalmic practitioners should, where practicable and not compromising clinical outcome, restrict corneal contact devices to single patient use to minimise a remote theoretical risk of transmission of new variant Creutzfeldt-Jakob disease (vCJD). This study reports on a modified technique of ultrasound A-scan biometry that complies with the MDA recommendations. METHODS: The right eyes of 37 consecutive hospital patients had a series of biometry readings taken with a Humphrey 820 A-scan instrument with a plane wave transducer use d conventionally and with the addition of a disposable latex cover. RESULTS: Intrasessional repeatability of axial length measurements was similar for conventional readings - mean difference 0.027 mm, 95% confidence intervals (CI) +/- 0.44 mm and those taken with a disposable cover (0.028 mm, CI +/- 0.38). Intersessional repeatability was equivalent with (0.002 mm, CI +.- 0.51) and without a cover (0.03 mm, CI +/- 0.51). Readings with a cover were not significantly different from those without (paired t test; p >0.05), but tended to be greater (mean difference 0.085 mm, CI +/- 0.60). CONCLUSIONS: These findings suggest that corneal contact biometry with a disposable cover is a viable and theoretically safer alternative to the conventional technique.
MH Adult; Aged; Aged, 80 and over; Biometry/*instrumentation; Disposable Equipment/standards; Equipment Design; Human; Middle Age; Observer Variation; Ophthalmology/*instrumentation; Reproducibility of Results; Ultrasonography/*instrumentation/standards
AD Department of Optometry and Neuroscience, UMIST, PO Box 88, Manchester M60 1QD, UK. kevin.cass@stud.umist.ac.uk
SP englisch
PO England