To measure abdominal wall compliance (AWC) during gynaecologic laparoscopy and assess its relation to the pelvic organ prolapse quantification (POP-Q) score of the same individual, and determine a relationship if present.

To characterize abdominal wall compliance (AWC), sterile reflective markers are attached to the abdominal wall by means of surgical tape, and the movement of these markers will be tracked with an optical tracker device. As during normal surgery, the intra-abdominal pressure (IAP) measured by the insufflator device will be recorded and stored on a secure computer with dedicated software. The pelvic organ quantification (POP-Q) score for each patient is determined pre-surgery as part of the standard of care. A biomechanical model will use reflective marker displacement (RMD) and IAP to calculate AWC. The POP-Q score will then be used to investigate a relation between AWC and degree of prolapse.

It is important to state that the trial does not intervene with the standard of care before- and during surgery. The used equipment is non-invasive and only requires about 5 minutes to be set up before the start of surgery. This set up comprises placing the optical tracker in the operating room such that it has a line of sight on the patient's abdomen and attaching the sterile markers to the abdominal wall. Therefore the trail does not add any additional risk to the surgery.

Each patient scheduled for gynecologic laparoscopy will be asked to participate in the study. If the patient wants to participate, she is presented the informed consent form (ICF). If both patient and clinician in charge sign the ICF, the patient is included in the study. The table below shows the patient specific information stored as part of the study.

Sample size calculation is based on a previous study (S61346), where we measured vaginal wall stiffness (the inverse of compliance) in patients with varying degrees of prolapse. 20 POP patients and 20 control group patients will be included.

Inclusion Criteria:

• All patients assigned to gynecologic laparoscopic surgery at UZ Leuven.

Exclusion Criteria:

• Patients that are unable to give consent: In case of dementia or other cognitive disorders.
• Patients that are unable to give consent: When they are unable to read and/or interpret the content of the informed consent form (ICF), which is written in Dutch.
• Patients that had had an earlier abdominoplasty or abdominal wall mesh implantation, or other operations that directly affect the biomechanical properties of the abdominal wall.