Laser Photocoagulation in Twin to Twin Transfusion Syndrome

Patients initially will be identified by ultrasound examination by their primary provider.
Consultation and subsequent ultrasound confirmation will be undertaken by our group. Patients
meeting the inclusion criteria will undergo extensive verbal counseling regarding the
clinical findings, prognosis, and management options. Those electing to proceed will sign
written informed consent documents.

More specifically, after initial referral to our center for TTTS management, patients will
undergo targeted ultrasound to confirm the diagnosis. If confirmed, patients will undergo
extensive counseling regarding various management options. Those patients electing to proceed
with selective laser photocoagulation (S-LPC) will undergo the informed consent process. The
S-LPC will be performed in the Labor and Delivery (L&D), Operating Room (OR) at the Regional
Medical Center, Regional One Health (RMC,ROH). In the majority of cases, maternal anesthesia
will be an epidural. In those cases where the patient is unable to lay supine due to an
enlarged uterus (resulting in maternal hypotension or respiratory insufficiency, or maternal
anxiety), general anesthesia with intubation will be administered. In rare cases, intravenous
sedation with infiltration of a local anesthetic into the skin, deep muscle, and fascia will
be used. Following the administration of maternal anesthesia, ultrasound will be performed to
assess fetal position, placentation, and select a site for insertion of the operative
instruments. A small skin incision will be made following administration of local anesthetic
to allow percutaneous access to the recipient gestational sac. An 18 gauge needle will be
inserted through the maternal abdomen and uterus into the gestational sac. Once secured in
place, the stylet will be removed and a J guide wire will be inserted through the needle. The
needle will be removed and a 10-12 Fr (3-3.4 mm) trocar and cannula will be inserted into the
sac over the guide wire. The trocar and guide wire will be removed and the fetoscopy
instruments will be introduced through the cannula. The procedure is performed under
continuous ultrasound guidance. After introduction of the fetoscope and operating sheath, the
placenta is inspected by direct visualization for communicating vessels between the recipient
and donor twin. A 400-600 micron laser fiber is introduced into the gestational sac via an
instrument channel in the operating sheath. The fiber is directed to the communicating
vessels, which are then ablated with thermal energy. An average of 7-15 sites will be
ablated. At the completion of the procedure the amniotic fluid volume in the recipient sac
will be reduced to a normal volume. Follow-up visits to track maternal and fetal progress
after the procedure will be scheduled with our group.

Inclusion Criteria:

- The device will be used in multifetal pregnancies affected with twin-to-twin
transfusion syndrome (TTTS) at less than 27 weeks of gestation

Exclusion Criteria:

- All other pregnancies not meeting inclusion criteria