Laser Photocoagulation in Twin to Twin Transfusion Syndrome

Brief Title

Laser Photocoagulation in Twin to Twin Transfusion Syndrome

Official Title

Fetoscopic Directed Laser Photocoagulation of Communicating Placental Vessels in Twin to Twin Transfusion Syndrome

Brief Summary

      Humanitarian use device (HUD): Use of the fetoscopy instrument sets for selective laser
      photocoagulation in the treatment of Twin to Twin Transfusion Syndrome (TTTS).

Detailed Description

      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.

Study Type


Primary Outcome

Laser ablation of placental anastomoses for treatment of severe TTTS and establishment of normalized blood flow between the fetal twins.


Twin to Twin Transfusion Syndrome


S-LPC:Selective Laser Photocoagulation

Study Arms / Comparison Groups

 S-LPC:Selective Laser Photocoagulation
Description:  S-LPC seals connecting vessels, normalizes flow between twins


* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Information

Recruitment Status


Estimated Enrollment


Start Date

April 2010

Completion Date

October 28, 2020

Primary Completion Date

August 15, 2020

Eligibility Criteria

        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




16 Weeks - 27 Weeks

Accepts Healthy Volunteers



Giancarlo Mari, M.D., MBA, , 

Location Countries

United States

Location Countries

United States

Administrative Informations



Organization ID


Responsible Party


Study Sponsor

University of Tennessee


 Regional Medical Center, Regional One Health

Study Sponsor

Giancarlo Mari, M.D., MBA, Principal Investigator, Prof. & Chair, UTHSC; Dir.,TN Inst. of Feto-Maternal & Infant Health; Dir., High-Risk Obstetrics Ctr of Excell., Regional Medical Ctr

Verification Date

January 2019