Sequential vs. Standard Laser Treatment of Twin-twin Transfusion Syndrome

USFetus Randomized Clinical Trial: Sequential vs. Standard Laser Treatment of Twin-twin Transfusion Syndrome

The investigators hypothesize that treatment of twin-twin transfusion syndrome (TTTS) using sequential laser photocoagulation of communicating vessels (SQLPCV) over the predominant method, selective laser photocoagulation of communicating vessels (SLPCV), may provide vascular stability to the donor fetus. The primary objective is to evaluate the perinatal outcome, specifically, donor intrauterine survival of TTTS managed by SQLPCV vs. SLPCV in a prospective, randomized trial.

Study Overview

• Status: Completed
• Conditions: Twin Twin Transfusion Syndrome
• Intervention / Treatment: Procedure: Selective laser photocoagulation of communicating vessels; Procedure: Sequential laser photocoagulation of communicating vessels.

• Study Type: Interventional
• Enrollment (Actual): 642
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90027
      • Hollywood Presbyterian Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 55 years (Child, Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Gestational age: 16 weeks, 0 days to 26 weeks, 0 days.

• Confirmed TTTS patients, who by definition meet the following sonographic criteria:

  • Single placenta.
  • Polyhydramnios: maximum vertical pocket ≥ 8 cm in the recipient twin, prior to amniodrainage.
  • Oligohydramnios: maximum vertical pocket ≤ 2 cm in the donor twin, prior to amniodrainage.
  • Thin dividing membrane (absence of twin peak sign) or absence of dividing membrane (monoamniotic).
  • Same gender, if visible.
  • Quintero Stages 1-4.
• Patients choosing laser therapy that have undergone prior therapeutic amniocentesis may be included.
• Patients with an anterior placenta may be included.
• Triplet gestations with two or three fetuses sharing the same placenta may be included.
• Patients must be able to give written informed consent.

Exclusion Criteria:

• Patients unable or unwilling to participate in the study or to be followed up.
• Patients unable to give written informed consent.
• Presence of major congenital anomalies that may not warrant surgery.
• Known unbalanced chromosomal complement.
• Prior intentional septostomy (purposely making a hole in the dividing membrane).
• Ruptured membranes.
• Chorioamnionitis.
• Abnormal intracranial ultrasound findings of either fetus to include, but not limited to: intraventricular hemorrhage, porencephalic cysts, hydrocephalus, Dandy-Walker syndrome, holoprosencephaly and agenesis of the corpus callosum. Isolated ventriculomegaly (atrium 10-19 mm) may or may not be used as exclusion criteria.
• Placental abruption.
• Active labor.
• Patient unwilling to receive blood products.
• Recipient twin with a middle cerebral artery peak systolic velocity > 1.5 multiples of the median (indicative of fetal anemia).
• Any other patient deemed inappropriate for the study by the principal investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Selective procedure; Selective laser photocoagulation of communicating vessels.	Procedure: Selective laser photocoagulation of communicating vessels
Experimental: Sequential procedure; Sequential laser photocoagulation of communicating vessels	Procedure: Sequential laser photocoagulation of communicating vessels.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To compare donor intrauterine survival (alive at birth) for those undergoing SQLPCV vs. SLPCV.	A comparison of donor survival at birth will be made between subjects assigned to the sequential (SQLPCV) procedure versus those assigned to the selective (SLPCV) procedure.	Birth

Secondary Outcome Measures

Outcome Measure	Time Frame
Surgical complications	21 post-operative days

Other Outcome Measures

Outcome Measure	Time Frame
Fetal/neonatal/infant outcomes	Birth to 6 months of life

Collaborators and Investigators

• Sponsor: University of Southern California
• Investigators: Principal Investigator: Ramen Chmait, MD, University of Southern California

Study record dates

Study Major Dates

• Study Start (Actual): June 9, 2010
• Primary Completion (Actual): April 30, 2023
• Study Completion (Actual): October 31, 2023

Study Registration Dates

• First Submitted: April 16, 2014
• First Submitted That Met QC Criteria: April 22, 2014
• First Posted (Estimated): April 24, 2014

Study Record Updates

• Last Update Posted (Actual): July 20, 2025
• Last Update Submitted That Met QC Criteria: July 16, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: Twin twin transfusion syndrome; Sequential laser photocoagulation of communicating vessels
• Additional Relevant MeSH Terms: Pathologic Processes; Disease; Infant, Newborn, Diseases; Hematologic Diseases; Anemia; Anemia, Neonatal; Syndrome; Fetofetal Transfusion
• Other Study ID Numbers: HS-09-00680