S A Ballantyne1, G O'Neill, R Hamilton, A S Hollman. 1. Department of Radiology and Clinical Physics, Royal Hospital for Sick Children, G46 7PD, Glasgow, UK. s.ballantyne@virgin.net
Abstract
AIM: To quantify the observer variation in the sonographic measurement of optic nerve sheath diameter (ONSD) in normal adults. MATERIALS AND METHODS: Sixty-seven normal adult volunteers underwent ultrasound examination of each eye by three independent observers using a 7 MHz sector probe. Three measurements were made of each eye by each observer and a mean value calculated for each eye. Median and 5th-95th centile values for both intra- and inter-observer variation were calculated for the three observers. RESULTS: The median intra-observer variation was +/-0.1 mm, with 5th-95th centile values of +/-0-0.4 mm. The median inter-observer variation was +/-0.2-0.3 mm, with 5th-95th centile values of +/-0-0.7 mm. Careful review of examination technique by the three observers after the first 17 examinations was shown to reduce both intra- and inter-observer variation. CONCLUSION: The sonographic measurement of ONSD is a readily learned, reproducible technique with low intra- and inter-observer variation. The average inter-observer variation (+/-0.2 mm) is comparable to the inherent variability of the ultrasound machine. The importance of standardisation of examination technique is stressed.
AIM: To quantify the observer variation in the sonographic measurement of optic nerve sheath diameter (ONSD) in normal adults. MATERIALS AND METHODS: Sixty-seven normal adult volunteers underwent ultrasound examination of each eye by three independent observers using a 7 MHz sector probe. Three measurements were made of each eye by each observer and a mean value calculated for each eye. Median and 5th-95th centile values for both intra- and inter-observer variation were calculated for the three observers. RESULTS: The median intra-observer variation was +/-0.1 mm, with 5th-95th centile values of +/-0-0.4 mm. The median inter-observer variation was +/-0.2-0.3 mm, with 5th-95th centile values of +/-0-0.7 mm. Careful review of examination technique by the three observers after the first 17 examinations was shown to reduce both intra- and inter-observer variation. CONCLUSION: The sonographic measurement of ONSD is a readily learned, reproducible technique with low intra- and inter-observer variation. The average inter-observer variation (+/-0.2 mm) is comparable to the inherent variability of the ultrasound machine. The importance of standardisation of examination technique is stressed.
Authors: Marc Steinborn; Melanie Friedmann; Christine Makowski; Helmut Hahn; Alexander Hapfelmeier; Hendrik Juenger Journal: Childs Nerv Syst Date: 2016-01-13 Impact factor: 1.475
Authors: Nicholas A V Beare; Sam Kampondeni; Simon J Glover; Elizabeth Molyneux; Terrie E Taylor; Simon P Harding; Malcolm E Molyneux Journal: Trop Med Int Health Date: 2008-10-13 Impact factor: 2.622
Authors: Mypinder S Sekhon; Paul McBeth; Jie Zou; Lu Qiao; Leif Kolmodin; William R Henderson; Steve Reynolds; Donald E G Griesdale Journal: Neurocrit Care Date: 2014-10 Impact factor: 3.210