Twin Twin Transfusion Syndrome (TTTS)

Question 1

What is the likelihood of developing TTTS in a monochorionic diamniotic twin gestation?

Answer 1

10-15%

Question 2

What are the ultrasound features that would lead you to suspect TTTS?

Answer 2

Donor: volume depleted, growth restricted, oligohydramnios

Recipient: polycythemic, heart failure, polyhydramnios, hypervolemic, hydrops

Question 3

What are the Quintero States of TTTS?

Answer 3

I: MVP <2 cm in donor sac, >8 cm recipient sac “poly/oli” sequence
II: I and no measurable fluid in donor “noncycling bladder”
Non-visualization of fetal bladder in donor > 60 min (donor fetus)
III: Absent/reversed umbilical artery diastolic flow, “critical Doppler” reversed ductus venosus a-wave flow, pulsatile umbilical vein flow
~50% risk of loss
IV: Hydrops Fetalis in one or both twins
V: Fetal demise of one or both twins

Question 4

When do you refer a patient for possible laser surgery for TTTS?

Answer 4

Stage II, III and IV

Question 5

How do you counsel the patient regarding the risks and benefits of laser therapy vs serial amnio drainage for TTTS?

Answer 5

Laser photocoagulation has better outcome (see Eurofetus trial)

Question 6

What are the fetal and neonatal outcomes following laser surgery for TTTS?

Answer 6

Survival overall is 74%, at least 1 85% and both 64%

Other complications include:
PPROM 
TAPS 
Brain lesions 
PVLM

Question 7

How do you follow a patient after laser surgery for TTTS?

Answer 7

Weekly x 2-3 wks 
If stable, every 2 wks 
Growths q4 wks 
28 antenatal testing
Delivery 34-36 weeks

Question 8

What are the potential complications that can occur post laser for TTTS?

Answer 8

Fetal complications (double and single intrauterine fetal death more likely to occur in donor, up to 20%, recurrence of TTTS, twin anemia-polycythemia sequence (TAPS), reversal of TTTS, cerebral lesions in either, persistent cardiac dysfunction (pulmonary valve disease), PPROM, iatrogenic mono/mono, pseudo amniotic band syndrome

Question 9

When do you recommend delivery following laser surgery for TTTS?

Answer 9

Goal 34-36 weeks

Usually delivery between 29-33 weeks

Question 10

Eurofetus trial:

Answer 10

Compared amniocentesis verses laser therapy in the setting of TTTS

Outcome measure: survival and neurologic disease

Results: laser group had more survival and less neurologic disease