Background:
The use of intra-operative ultrasound has been widely implemented amongst other specialties.
However, within gynaecological surgery, it is not as commonly recognized, despite evidence
that it can be used as an adjunct to improving minimally invasive surgical techniques. This
is primarily due to the improved visualization of the operative field, which can assist more
technically difficult surgical procedures, thus minimizing intra-operative complications. The
application of ultrasound guidance within gynaecological procedures have included
predominantly ovarian cyst aspiration, in vitro fertilization and removal or insertion of
intra-uterine devices. Although pre-operative imaging provides procedural planning, it cannot
compare to the information gained from real time imaging. For example, in previous studies,
intra-operative ultrasound detected more myomas during myomectomy than pre-operative
transvaginal imaging. Furthermore, it provides the potential to assess lesion margins,
ensuring resection of pathology is complete with negligible damage to surrounding healthy
tissues. This is consistent with a recent systematic review, which also demonstrated that
albeit a novel technique, amongst various case series, pathology can be safely resected
without incurring injury to healthy reproductive tissue. Therefore, intra-operative
ultrasound has the potential to improve surgical accuracy, reduce complications and improve
patient safety. The application of intra-operative ultrasound as an adjunct to fertility
sparing surgery has not been widely researched, with only a few case series reporting
surgical outcomes on patients undergoing treatment for pre-malignant or malignant pathology.
The aim of this study therefore, is to determine the efficacy of this surgical technique in
the management of benign pathology, including the surgical resection of ovarian cysts.
Hypothesis:
Intra-operative ultrasound will prove a significant method of fertility preservation surgery,
as measured by a significantly reduced decrease in Anti-Mullerian Hormone (AMH) and antral
follicle count (AFC) at 3 and 6 months post-operatively, when compared to the control group.
Study Design:
This will be a multi-centre prospective cohort study carried out as a non-blinded randomised
controlled trial. Women will be allocated to either a control group of laparoscopic ovarian
cystectomy performed without ultrasound guidance, or to the experimental ultrasound guided
laparoscopic ovarian cystectomy (UGLOC) group. All surgeons operating and women recruited to
the study will be aware of which group they have been allocated to from the beginning of
their participation to the study. The research team aims for equal sample sizes in both
groups.
Recruitment:
Women referred to the outpatient gynaecology clinic with a suspected ovarian cyst will be
asked about their clinical history and undergo a pelvic transvaginal ultrasound scan (2D and
3D ultrasonography) as part of routine clinical care. If an ovarian cyst is seen on
ultrasound, it will be assessed according to local protocols based on simple descriptors and
International Ovarian Tumour Analysis (IOTA) simple rules. Depending on the severity of
symptoms, nature of the cyst and fulfilment of the inclusion criteria and if the woman is
suitable for surgical management, she will then be invited to participate in the study.
Participants will be recruited from various general gynaecology clinics, as well as
specialist clinics including: ovarian cyst clinic, the IOTA and Rapid access clinics across
Imperial and University College London Hospital.
Following consent of participation, the woman will be assigned to either a control or
experimental group. A separate research group, not directly affiliated with the project will
perform the randomisation process. The research group will print x "control group" labels and
x "experimental group," in which each label is then sealed into an individual envelope. All
envelopes will be numbered and issued in sequence. During the recruitment process, once the
participant has given consent to participate in the trial, a member of the research team will
select the envelope in sequence, which will then assign the participant to a group. This will
prevent the person performing the randomisation from selecting another envelope if they are
not happy with the group allocation.
For this study, it will not be necessary to postpone diagnostic procedures or treatment, and
participation will not influence normal treatment.
Surgical Intervention:
The same surgeons will operate on women in both the control and experimental group. This will
aim to exclude bias which may otherwise attribute findings to the surgeon operating. Surgery
will be performed at Imperial Healthcare NHS Trusts and at the University College London
Hospitals NHS Foundation Trust by an experienced clinician.
Data Collection:
The research team will collect the following data: Participant demographics including age,
BMI, gravida, parity and gynaecological surgical history. Pre-operative data will include
findings from the diagnostic transvaginal scan and measure of ovarian reserve: AMH and AFC.
Intra-operative data will include transvaginal findings during surgery (in the experimental
group only), such as cyst location and size or any new lesions noted. Residual ovarian volume
post cystectomy will also be measured intraoperatively. Histology data will include the
histological diagnosis of the ovarian cyst and volume of normal ovarian tissue excised during
the cystectomy measured as per margins in mm. Outcomes following surgery including duration
of surgery (mins), length of hospital stay (days) and post operative complications will be
recorded.
Follow up:
Post-operatively, participants will return to their respective hospital gynaecology clinic
responsible for the care and management of the ovarian cyst for follow up at 3 and 6 months.
During the appointment a blood test will be taken to assess ovarian reserve by measuring the
AMH level. The outpatient gynaecology nurse in clinic or research staff will be responsible
for taking the blood sample and will only require one EDTA bottle (yellow top) to be filled
(20-40mls). The blood samples will be processed by Imperial College Healthcare Trust
laboratories or University College London Hospitals NHS Foundation Trust, depending on the
site taken, and will be discarded as per local protocol once the AMH has been determined.
There are no specific storage or transfer requirements outside of normal practice. Therefore,
samples will be 'podded' to the labs once taken in the usual way. In addition, an ultrasound
will be performed during the follow up appointment by an experienced gynaecology specialist
trainee or Consultant to assess the AFC and preserved ovarian volume of tissue remaining. Any
incidental findings identified on ultrasound scan of gynaecological pathology, will be
managed by the responsible clinician and the participants GP will be informed by letter.
Follow up appointments should take approximately 20 minutes. The two blood tests and two
ultrasound scans carried out during the follow up process are considered standard clinical
practice, and therefore not considered additional investigations for the purpose of this
research study.
The majority of participants are likely to be discharged following their 2nd clinic
appointment 6 months post- surgery, whereby no further involvement in the study is required.
If a participant becomes pregnant during the follow up period, clinic appointments will be
deferred to 3 and 6 months post-partum.