Open magnetic resonance (MRO) is an advanced technology where the configuration of the magnet allows images to be captured with patients sitting and standing as well as supine. This is relevant where posture and the effect of gravity have an impact on the region imaged; pelvic organ prolapse (POP) is an example. In POP, MRO provides standing images that allow detection of organ prolapse due to the effects of posture and gravity; and three-dimensional (3D) models generated from 2D images further enhance definition of the morphological features of POP.
Purpose:
To describe how high quality open MR 2D images can be modeled to create three dimensional images of the pelvic structures and enhance evaluation of patients with POP.
Material and Methods:
A cohort of 31 women (13 with POP and 18 asymptomatic controls) were recruited for MRO studies using a 0.5 T scanner. Axial and sagittal T2-weighted pelvic scans were obtained standing, sitting and supine. Manual segmentation using Analyze 12.0 software was then used to construct the 3D models.
Results:
The 3D modeling method developed generated images that were realistic and clearly revealed the extent of downward descent of pelvic structures in patients with POP. Generating 3 D images from sitting and standing 2D images enabled the extent and detail of organ descent to be better defined.
Conclusion:
A new protocol for open MR imaging combined with methodology for 3D image modeling of the female pelvis provides enhanced anatomic definition and will allow more comprehensive evaluation of the extent of POP due to the impact of posture and gravity.
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