In utero repair of myelomeningocele: experimental pathophysiology, initial clinical experience, and outcomes.
OBJECTIVE
Experimental work raises the possibility that in utero repair of myelomeningocele (MMC) may improve lower extremity, bladder, and bowel function, ameliorate the Arnold-Chiari malformation, and decrease the need for postnatal shunting.


METHODS
We previously developed fetal lamb models to create and reverse lower extremity damage and the Arnold-Chiari malformation in utero. We then applied our extensive experience with fetal surgery, including fetal endoscopic (fetoscopic) surgical manipulation, to develop techniques for MMC repair.


METHODS
A tertiary referral center.


METHODS
All patients treated between 1998 and 2002 for a prenatally diagnosed MMC.


METHODS
Either fetoscopic MMC repair, fetoscopic patch repair, or limited maternal hysterotomy and microsurgical 3-layered fetal MMC repair was performed.


METHODS
Gestational age at delivery, survival, neurologic outcome, and need for ventricular shunting at 1 year.


RESULTS
Complete fetoscopic repair was accomplished in 1 fetus. Two other fetuses underwent partial fetoscopic procedures. The remaining 10 patients underwent limited maternal hysterotomy and microsurgical 3-layered fetal MMC repair. Four of 13 patients died, and the mean gestational age at delivery of 11 fetuses born alive was 31 weeks. Five of 9 required ventricular shunting by age 1 year. In 2 patients, lower extremity function improved by more than 2 vertebral levels compared with prenatal ultrasonography. Five of 10 patients who lived longer than 3 weeks required postnatal wound revision within 7 days after birth.


CONCLUSIONS
Fetoscopic repair, although feasible, does not yet yield optimal surgical results. Open surgical repair before 22 weeks' gestation is physiologically sound and technically feasible. One third of patients appear to be spared the need for a shunt at age 1 year, but improvement in distal neurologic function is less clear. Additionally, fetal mortality is associated with this procedure. Our results complement the data published by groups at Children's Hospital of Philadelphia, in Pennsylvania, and Vanderbilt University, Nashville, Tenn. A National Institutes of Health-sponsored prospective randomized trial is now underway at these 3 centers to compare fetal repair with postnatal repair.
Farmer
Diana L
DL
Departments of Surgery and Neurosurgery and the Fetal Treatment Center, University of California, San Francisco, CA 94143-0570, USA. farmerd@surgery.ucsf.edu
von Koch
Cornelia S
CS
Peacock
Warwick J
WJ
Danielpour
Moise
M
Gupta
Nalin
N
Lee
Hanmin
H
Harrison
Michael R
MR
D000328:Adult; D000818:Animals; D005260:Female; D005315:Fetal Diseases / Q000503:physiopathology / Q000601:surgery*; D005332:Fetoscopy; D005333:Fetus / Q000601:surgery*; D005865:Gestational Age; D006801:Humans; D020883:Hysterotomy; D008591:Meningomyelocele / Q000503:physiopathology / Q000601:surgery*; D008866:Microsurgery; D011247:Pregnancy; D012756:Sheep / Q000196:embryology; D016896:Treatment Outcome