Evaluation of Gellhorn pessary on the anatomy of the pelvic floor and the pelvic organs in patients with pelvic organ prolapse using upright MRI

Pelvic organ prolapse (POP) is a common problem in middle aged women. In the
Netherlands, the prevalence of symptomatic POP in women between 45-85 years is
11.4% [1]. A pessary is a relatively inexpensive treatment option that reduces
POP symptoms. However, in 56% of the cases complications occur and the success
rates after 1 year are only between 50 and 73% [17]-[19]. Furthermore,
researchers and clinicians have different thoughts about the position of a
pessary inside the body and research into risk factors associated with
unsuccessful pessary fitting shows conflicting results [13], [14], [20], [21].
Therefore, from 2022 to 2024 our group executed the EPPA study
(NL74061.091.20), were we included healthy controls, patients with successful
ring pessary fitting and use and patient with ring pessary dislodgement. We
obtained valuable new insights on the position of a ring pessary in the pelvis
and on its support mechanism. Several peer reviewed papers have been published
using the EPPA data, and an additional three more papers are in preparation or
under submission.
The majority of the 29 patients in our *unhappy pessary group*(patients whom
discontinued ring pessary use, mainly due to ring drop-out) did continue with a
pessary, but from a different type. Specifically the Gellhorn pessary.

It is needed to investigate the position, support and working mechanism of this
Gellhorn pessary and its influence on the pelvic organs to gain more insight in
the variety of pelvic pessary support mechanisms and the factors associated
with successful pessary fitting.

Imaging techniques can be used to evaluate the position of a pessary. Magnetic
resonance imaging (MRI) is an imaging technique in which three dimensional
imaging of multiple compartments is possible. The additional value of the use
of upright MRI is that pessary fitting can be evaluated in the position in
which the extent of prolapse is significantly larger than in supine position
[26].
There is a large amount of unknowns considering the effect of a pessary on the
pelvic organs. Insight in these unknowns may be useful to optimize the pessary
treatment and reduce the complication rate and the amount of unsuccessful
fittings.

The primary objective is to evaluate the supporting mechanism of the pelvic
floor for a Gellhorn pessary in patients with pelvic organ prolapse immediately
after insertion and one week after insertion of the Gellhorn pessary.

Secondary Objectives:
• Evaluate which parameters are associated with a change of the position and
shape of the pelvic organs due to insertion of a Gellhorn pessary in successful
pessary fitting.
• Evaluate the position and orientation of the Gellhorn pessary in successful
pessary fitting.
• Evaluate if the parameters measured using upright MRI can be translated to
parameters which can be measured in imaging techniques used in clinical
practice.
• Evaluate a difference in Gellhorn pessary position between the moment after
insertion and one week of pessary wearing.
• Evaluate if there is a correlation between the position and orientation of
the pessary and anatomical aspects of the levator ani muscle.
- Evaluate if there is a correlation between the position and orientation of
the pessary and anatomical aspects of the levator ani muscle

A prospective cohort study in which the participants will undergo upright and
supine MRI in two visits: (1) without the pessary and immediately after
Gellhorn pessary insertion and (2) one week after Gellhorn pessary insertion.
In addition, the following questionnaires are filled out during the first
visit: A general questionnaire (as previously used in the EPPA study), PFDI-20
and a pessary questionnaire. Before the first MR scan, the POP-Q measurement
will be repeated to define the amount recurring prolapse after pessary removal.

This study consists of two scans on the first day and one scan after a week.
The scan protocol will be executed at the Esaote 0.25T MRI scanner. First, the
participant will be scanned in upright position. Several scans will be acquired
for a maximum of 20 minutes. Thereafter, the same scans will be acquired in
supine position.

In total, the same protocol will be executed three times: first without the
pessary inserted. Approximately 24 hours before the first scan the patient will
remove her pessary or have her pessary removed at home or at the hospital.
Before the first scan, the POP-Q measurement will be repeated to determine the
amount of recurring prolapse after pessary removal. After finishing the scan
the Gellhorn pessary is inserted and a second scan is performed in the same
manner. One week later the third scan is performed.

During the scanning procedure the participant needs to lie or stand still. In
upright position, some people may experience some dizziness because of this. To
prevent this, the participant is encouraged to move her toes between the
different scans/sequences. If dizziness is noticed, the scan will be aborted
immediately and the participant is turned back to the horizontal position. The
risks associated with MRI are negligible.