Fetoscopy in Complicated Fetoscopy in Complicated Fetoscopy in Complicated Fetoscopy in Complicated

Twin PregnanciesTwin PregnanciesTwin PregnanciesTwin Pregnancies

Basky ThilaganathanBasky ThilaganathanBasky ThilaganathanBasky Thilaganathan

Fetal Medicine UnitAcademic Department of

Obstetrics and Gynaecology

St.George’s Hospital Medical School

Monochorionic twins

Who needs fetoscopy?

Absolute indications

Stage 3 and 4 TTTS

Relative indicationsRelative indications

Stage 1 and 2 TTTS

Selective IUGR

Acute TTTS

Discordant severe abnormality

TRAP sequence

Complications of MCDA

twins

Size Fluid

TTTS Discrepant Poly-oligo

Acute ITT Same Poly-oligo

Selective IUGR Discrepant Normal-oligo

Selective IUGRSevere IUGR in stuck

(donor) twin

NORMAL co-twin

(no polyhydramnios)

Rarest form of twin

vascular complication

Variable UA Doppler

~30% CP risk with

co-twin death

Acute TTTSPoly-oligohydramnios

NO evidence of

growth discrepancy

Preterm delivery

15% recurrence risk

Abnormal umbilical

Doppler

Twin-Twin

TransfusionTransfusion

Syndrome

Twin-to-twin transfusion

Twin-to-twin transfusion

Operative

techniquetechnique

Operative Fetoscope

Sono-endoscopic technique

Inter-twin membrane

Non-selective Technique

Selective TechniquesVascular equator

Thilaganathan B et al. 2000 Ult Obs Gyn

Laser Sequence

Posterior placenta

Donor North

Recipient South

Arteries dark

Laser Sequence

Two A-V connections

Maternal movement

Anterior placenta

Aperture size

Depth of field

Size of vessels

Distance of fibre

Laser Sequence

Distance of fibre

Laser sequence

Results

70%

75%

80%

Non selective

Senat et al

n=35

Selective

Quintero et al

n=74

Equatorial

n=77Non selective 30-90 minutesVille et al 1995 NEJM

Selective median 73 min (range 20-178 min)Quintero et al 2000 Ultrasound OG

Equatorial median 15 min (range 5-25 min)

Survival n

No. of

pregnancies

% of total

pregnancies

0 survivors 20 26%

At least one survivor 57 74%

One survivor 26 34%

Two survivors 31 40%

77 monochorionic twin pregnancies

All severe TTTS at Quintero

stage III (n=68) or IV (n=9)

60%

65%

Ierullo A et al. BrJOG. 2007;114:689-93

Post-operative AssessmentUltrasound and Doppler

assessments at 6hrs

2 weeks and 6 weeks

2 cases of fetal

anaemia post-laser

1 repeat procedure

TRAP

SyndromeSyndrome

TRAP syndromeTwin Reversed Arterial

Perfusion Syndrome

1% of MC pregnancies

1:35,000 births

Acardiac/acephalic mass

Pump twin

Close cord insertions

2-vessel cord

Retrograde blood flow

TRAP syndrome50-75% pregnancy loss

Depends on size of acardiac mass

Pregnancy loss due to:

• Hyperdynamic cardiac failure

Beware of intermittent

reversed flow

• Hyperdynamic cardiac failure

• Preterm PROM or labour

TRAP syndromeFetoscopic laser ablation

80% survival rate

Hecher K et al. Ult Obstet Gynecol

2006;28:688-91

TRAP syndromeCord occlusion of 51

patients with 65% survival

Quintero RA et al.

AmJOG 2006;194:982-91

Intrafetal techniques have:

Later gestation at delivery

Lower PROM rates

Fewer technical failures

Tan and Sepulveda

Ult Obstet Gynecol 2003;22:409-19

TRAP syndrome

Radiofrequency ablation of

29 patients with 86% survival

Lee H et al.

AmJOG 2007;196:459AmJOG 2007;196:459

First trimester ultrasound-

guided interstitial laser

All 11 cases survived

St Georges unpublished