Intraoperative detection of c-section scar dehiscence with a light source
| ISRCTN | ISRCTN60638492 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN60638492 |
| Secondary identifying numbers | SLS20240901 |
- Submission date
- 05/09/2024
- Registration date
- 10/09/2024
- Last edited
- 14/11/2024
- Recruitment status
- No longer recruiting
- Overall study status
- Ongoing
- Condition category
- Pregnancy and Childbirth
Plain English summary of protocol
Background and study aims
As a result of the rising caesarean rate, uterine scar dehiscence (niche) is getting more prevalent. Depending on the imaging techniques and definitions, it has a prevalence of 19-84%. Many of these patients have a desire for a subsequent pregnancy. In women with a niche, a higher risk of uterus rupture is found during the subsequent pregnancy if the remaining uterus wall is thin (<3mm). Consequently, surgically is recommended to repair the niche before the next pregnancy. The surgery is performed minimally invasive with a conventional laparoscopy or a robot-assisted laparoscopy with for example the DaVinci® robot. For safer surgery and faster scar detection, the Scar-Light-System (SLS) was invented. It is an intra-uterine manipulator with an integrated, scalable light source. In planned future development, the SLS will also be equipped with image processing. The goal is to perform a diaphanoscopy through the defect zone under ambient surgery light conditions for the localisation of the niche, stabilization of the uterus, and to acquire data for developing image processing algorithms.
Who can participate?
Female patients aged between 18 and 50 years old with uterine scar dehiscence (niche) who need a laparoscopic repair (remaining uterine wall <3mm)
What does the study involve?
Patients meeting the inclusion criteria who agree to participate in the clinical investigation must sign the study-specific informed consent form prior to surgery.
The expected duration for light application is 10–30 minutes until the niche is detected. Patients will be recruited from the gynecological outpatient clinic at the Department of Gynecology, University Hospital Zurich. During gynecological consultations, the indication for laparoscopic niche repair will be established. All patients participating in the study will be informed about the risks and benefits of the laparoscopic isthmocele repair, as well as the specific risks, benefits, and mechanisms associated with the SLS manipulator.
Following the surgery, patients will typically stay in the hospital for one or two nights, with a follow-up visit scheduled six weeks postoperatively.
What are the possible benefits and risks of participating?
Not provided at time of registration
Where is the study run from?
University Hospital Zurich (Switzerland)
When is the study starting and how long is it expected to run for?
January 2022 to October 2025
Who is funding the study?
Investigator initiated and funded
Who is the main contact?
Prof Cornelia Betschart, cornelia.betschart@usz.ch
Contact information
Public, Scientific, Principal Investigator
Department of Gynecology, University Hospital Zurich, Frauenklinikstrasse 10
Zürich
8091
Switzerland
 ORCID ID |
0000-0002-0467-0170 |
|---|---|
| Phone | +41 44 255 52 03 |
| cornelia.betschart@usz.ch |
Study information
| Study design | Pilot proof-of-concept study |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Non randomised study |
| Study setting(s) | Medical and other records, University/medical school/dental school |
| Study type | Diagnostic, Safety |
| Scientific title | Pilot project of an intra-uterine manipulator with integrated, scalable light source with image processing system for correction of uterine scar dehiscence (niche) |
| Study acronym | SCAR-LIGHT-SYSTEM |
| Study objectives | The niche/defect zone in the c-section scar can be localized by diaphanoscopy through the scar tissue under ambient surgery light condition. The manipulator further allows the stabilization of the uterus. The SLS acquires data for developing image processing algorithms. |
| Ethics approval(s) |
Not yet submitted, Ethics committee of the Canton Zurich (Stampfenbachstrasse 191, Postfach, Zürich, 8091, Switzerland; +41 43 2597970; info.kek@kek.zh.ch) |
| Health condition(s) or problem(s) studied | Women with a isthmocele (c-section scar dehiscence) |
| Intervention | Due to the increasing rates of caesarean sections, there is a growing prevalence of uterine scar dehiscence (niche) and subsequent niche repair. Women with a niche and a thinner remaining uterine wall (<3 mm) face a higher risk of uterine rupture during subsequent pregnancies, prompting a recommendation for surgical niche repair before the next pregnancy. This surgery is minimally invasive and can be performed via conventional laparoscopy or robot-assisted laparoscopy, such as with the DaVinci® robot. For enhanced safety and more efficient scar detection during surgery, the Scar-Light System (SLS), model v1.0, was developed. The SLS is an intrauterine manipulator equipped with an integrated, scalable light source and an image processing system. It is designed to perform diaphanoscopy through the defect zone under ambient surgical lighting to localize the niche and stabilize the uterus. The device is manufactured by Fachhochschule Nordwestschweiz, Hochschule für Life Sciences, Institut für Medizintechnik und Medizininformatik, Muttenz, Switzerland. It is not yet CE-marked and does not have a registered UDI. Patients meeting the inclusion criteria who agree to participate in the clinical investigation must sign the study-specific informed consent form prior to surgery. The SLS manipulator comprises two main components: a light rod and an adjustment piece. The light rod extends from the intrauterine illuminating tip to the external handle, and the maximum length of the tip is fixed to prevent rupture or tearing of the uterus. The adjustment piece has a conical design at its proximal end, which helps secure the device to the cervix, stabilizing it and preventing gas escape from the uterus. The intrauterine fiber optic tip of the SLS shines through the niche, and the defect site is detected as a halo sign under laparoscopic view. Preclinical safety testing of the SLS included in-vitro experiments on excised uteri at the Institute of Pathology, University Hospital Zurich (USZ), and assessments of biological, mechanical, and electrical safety. The device has a 12-hour battery life, is reusable (autoclave-compatible), features adjustable light intensity, and is constructed from rigid materials for the stabilization and isolation of parauterine tissue, with a maximum temperature increase of less than 4°C in the surrounding tissue. The tip of the device is made of polymethyl methacrylate (PMMA) and is translucent to allow light emission, while the conical adjustment piece stabilizes the manipulator and prevents gas escape. The expected duration for light application is 10–30 minutes until the niche is detected. Patients will be recruited from the gynecological outpatient clinic at the Department of Gynecology, University Hospital Zurich. During gynecological consultations, the indication for laparoscopic niche repair will be established. All patients participating in the study will be informed about the risks and benefits of the laparoscopic isthmocele repair, as well as the specific risks, benefits, and mechanisms associated with the SLS manipulator. Following the surgery, patients will typically stay in the hospital for one or two nights, with a follow-up visit scheduled six weeks postoperatively. |
| Intervention type | Device |
| Pharmaceutical study type(s) | Not Applicable |
| Phase | Phase I |
| Drug / device / biological / vaccine name(s) | Scar-light-system |
| Primary outcome measure | Measured at the time of the procedure: 1. Light detection through the niche (yes/no) 2. Light intensity intraabdominal. The SI unit of light intensity is lumen by steradian (lm/sr) measured as candela (cd) (1 cd = 1 lm/sr) 3. Light intensity through the niche in comparison to the surrounding intraabdominal light intensity (measured in %) |
| Secondary outcome measures | Measured at the time of the procedure, unless noted otherwise: 1. Time for installation of the SLS (min) 2. Surgery time from the start of laparoscopy to detection of the niche (min) 3. Surgery time from detection of the niche to excision (min) 4. Surgery time from excision to the closure of the niche (3-layered suture) - complete surgery time (min) 5. Blood loss during surgery (ml) 6. Thickness of the niche tissue intraoperatively compared with the preoperatively measured sonographic thickness of the residual myometrium over the niche (mm) 7. Perioperative and postoperative complications (Clavien-Dindo classification) at time of operation and 6 weeks follow up 8. Subjective characteristics such as surgeon satisfaction and difficulty of the procedure measured using a Likert scale after the procedure 9. Safety outcomes measured using patient records |
| Overall study start date | 01/01/2022 |
| Completion date | 31/10/2025 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 50 Years |
| Sex | Female |
| Target number of participants | 5 |
| Key inclusion criteria | 1. Female patients with uterine scar dehiscence (niche) who need a laparoscopic repair (remaining uterine wall <3mm) 2. Signed general consent/informed consent 3. Patients ≥18 years |
| Key exclusion criteria | 1. Missing signed general consent/informed consent 2. Contraindications to general anaesthesia 3. Not knowledgeable in the German language |
| Date of first enrolment | 01/02/2025 |
| Date of final enrolment | 30/06/2025 |
Locations
Countries of recruitment
- Switzerland
Study participating centre
Zürich
8091
Switzerland
Sponsor information
Government
Einsteinstrasse 2
Bern
3005
Switzerland
| Phone | +41 58 461 61 61 |
|---|---|
| een@innosuisse.ch | |
| Website | https://www.innosuisse.admin.ch/en/about-us |
"ROR" |
https://ror.org/05a2bhn71 |
Funders
Funder type
Other
No information available
Government organisation / National government
- Alternative name(s)
- Innosuisse - Swiss Innovation Agency, Innosuisse - Agence suisse pour l’encouragement de l’innovation, Innosuisse - Agenzia svizzera per la promozione dell’innovazione, Swiss Innovation Agency, Innosuisse, Innosuisse
- Location
- Switzerland
Results and Publications
| Intention to publish date | 31/12/2025 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Stored in publicly available repository |
| Publication and dissemination plan | Planned publication in a Doctoral thesis |
| IPD sharing plan | The datasets generated during and/or analysed during the current study will be stored in a publicly available repository. Original raw data of the study will be shared with the thesis at the Zurich Open Repository and Archive: https://www.zora.uzh.ch/. |
Editorial Notes
14/11/2024: The following changes were made:
1. The recruitment start date was changed from 01/11/2024 to 01/02/2025.
1. The recruitment end date was changed from 31/03/2025 to 30/06/2025.
10/09/2024: Trial's existence confirmed by Swiss ethics
