Are pancreatic IPMN volumes measured on MRI images more
reproducible than diameters? An assessment in a large single-institution
Farnaz Najmi Varzaneh
Mounes Aliyari Ghasabeh
Ralph H. Hruban
Anne Marie O’Broin-Lennon
Ihab R. Kamel
Received: 9 October 2017 / Revised: 9 December 2017 / Accepted: 20 December 2017 / Published online: 5 February 2018
European Society of Radiology 2018
Objectives To assess reproducibility of volume and diameter measurement of intraductal papillary mucinous neoplasms (IPMNs)
on MRI images.
Methods Three readers measured the diameters and volumes of 164 IPMNs on axial T2-weighted images and coronal thin-slice
navigator heavily T2-weighted images using manual and semiautomatic techniques. Interobserver reproducibility and variability
Results Interobserver intraclass correlation coefficients (ICCs) for the largest diameter measured using manual and semiauto-
matic techniques were 0.979 and 0.909 in the axial plane, and 0.969 and 0.961 in the coronal plane, respectively. Interobserver
ICCs for the volume measurements were 0.973 and 0.970 in axial and coronal planes, respectively. The highest intraobserver
reproducibility was noted for coronal manual measurements (ICC 0.981) followed by axial manual measurements (ICC 0.969).
For the diameter measurements, Bland-Altman analysis revealed the lowest interobserver variability for manual axial measure-
ments with an average range of 95% limits of agreement (LOA) of 0.68 cm. Axial and coronal volume measurements showed
similar 95% LOA ranges (8.9 cm
and 9.4 cm
Conclusions Volume and diameter measurements on axial and coronal images show good interobserver and intraobserver
reproducibility. The single largest diameter measured manually on axial images showed the highest reproducibility and lowest
variability. The 95% LOA may help define reproducible size changes in these lesions using measurements from different readers.
• MRI measurements by different radiologists can be used for IPMN follow-up.
• Both diameter and volume measurements demonstrate excellent interobserver and intraobserver reproducibility.
• Manual axial measurements show the highest interobserver reproducibility in determining size.
• Axial and coronal volume measurements show similar limits of agreement.
• Manual axial measurements show the lowest variability in agreement range.
Magnetic resonance imaging
Reproducibility of results
ACR American College of Radiology
CI Confidence interval
CT Computed tomography
ICC Intraclass correlation coefficient
IPMN Intraductal papillary mucinous neoplasm
LOA Limits of agreement
MDCT Multidetector computed tomography
MRCP Magnetic resonance cholangiopancreatography
* Ihab R. Kamel
Russell H. Morgan Department of Radiology and Radiological
Sciences, Johns Hopkins University School of Medicine, 600 N
Wolfe St, Room 143, Baltimore, MD 21287, USA
Department of Pathology, Johns Hopkins Medical Institutions, 1550
Orleans Street, Baltimore, MD 21231, USA
Division of Gastroenterology, Johns Hopkins Medical Institutions,
Baltimore, MD, USA
European Radiology (2018) 28:2790–2800