**9. Conclusions**

seen. When a supine midsagittal single-shot fast SE image obtained at 0.5 T (Panel A) and the corresponding image in standing (Panel B) also the corresponding image in sitting position (Panel C) T2-weighted sagittal images of the female midline pelvic floor structures are compared, elongation of the bladder below the pubococcygeal reference line identifies significant

**Figure 1.** Anterior views of sagittal images show gravity-induced quantification prolapse. When a supine midsagittal single-shot fast SE image obtained at 0.5 T (panel A) and the corresponding image in standing (panel B) T2-weighted sagittal images of the female midline pelvic floor structures are compared, elongation of the bladder below the pubococcygeal reference line identifies significant prolapse when this patient is standing. A) Sagittal MRI image of female pelvis in the supine position, B) Sagittal MRI image of female pelvis in the standing position, C) Sagittal MRI

An additional component for more comprehensive evaluation of POP is to generate 3D images. After mid-sagittal pelvic MRI scans are complete, the images are transmitted to a workstation for processing to generate 3D models. On average, 40 axial images were combined to generate each 3D model. The data were first segmented to anatomically major components, including bladder, urethra, vagina, uterus, rectum, obturator internus, and all three components of the levator ani (puborectalis, iliococcygeus, and coccygeus) using manual editing. Old reference 3D reconstruction is labor intensive and hence costly. However, the resulting images yield a huge amount of detailed information that simply cannot be obtained from 2D images. Moreover, use of mathematical modeling will be helpful in the future to assist in defining the relationships of organs and quantifying mobility and pressure gradients to resolve questions of continence and pelvic floor prolapse [47]. Further, advantages of 3D reconstruction include the additional data provided for patient–clinician interaction to enhance understanding, more comprehensive surgical planning, and to advance medical research, and education [46]. A three-dimensional model of the levator can be produced for living individuals and muscle

The limitations include high cost and relative complexity of acquiring the initial images and the requirement for computer hardware and dedicated software [46]. Examples of the 3D

prolapse when this patient is standing.

image of female pelvis in the sitting position.

28 Pelvic Floor Disorders

**8. 3D computer-generated images**

volume calculated old reference.

imaging of the female pelvic floor can be seen in **Figure 2**.

Physicians should be aware that as upright open MRI becomes available this form of imaging will offer new levels of anatomic details relevant to a more accurate staging of POP and improved allocation to medical or surgical treatment. In POP, posture and gravity impact pelvic organ position, pelvic floor muscle integrity, degree of prolapse, and symptom severity. Importantly, while guidelines for clinical evaluation include recognition of the effects of posture, current imaging modalities are not always able to capture this aspect of prolapse. Ultrasound is a practical and widely available imaging modality. In patients who cannot bear MRI, CT may be beneficial as an alternate diagnostic process, but radiation is high. MRI provides multiplanar imaging and superior soft tissue contrast, permitting evaluation of the pelvic floor levator ani muscle in detail, but current imaging is limited to the supine position.

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Effects of Posture and Gravity on Pelvic Organ Prolapse http://dx.doi.org/10.5772/intechopen.77040 31

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Reference lines related to bony anatomical landmarks allow prolapse to be quantified. 3D image reconstruction from 2D MRI images provides information beyond that acquired from 2D studies. Our upright open MRI imaging and 3D protocol makes comprehensive diagnostic imaging available that improves the accuracy of diagnosis and staging of POP.
