Serial assessment of lower extremity motor function over the first 12 months of life in infants that underwent minimally-invasive fetoscopic surgery for spina bifida aperta at the University Hospital of Gießen-Marburg 2010 – 2013

Purpose: Minimally-invasive fetoscopic patch coverage of spina bifida aperta aims at improving postnatal motor outcome of affected fetuses. The purpose of this interim-analysis is to provide early clinical data on motor function during the first year of life.

Patients and methods: Anatomical level and motor function level of the lower extremities were assessed after delivery (A1), as well as at three (A2) and at twelve months of life (A3). The difference between functional and anatomical motor function level was recorded at each presentation. Cumulative data were recorded and compared with data from the motor outcome observed at 30-months in prenatally operated and control children from the MOMS-trial (Adzick et al. A randomized trial of prenatal versus postnatal repair of myelomeningocele. N Engl J Med. 2011 Mar 17;364(11):993 – 1004).

Results:

Tab. 1: Anatomical versus Functional

Difference “functional minus anatomical level”	Gießen A1 postnatal	Gießen A2 3 months	Gießen A3 12 months	MOMS Fetal surgery 30 months	MOMS Control group 30 months
-2 or worse	0	0	0	13%	28%
-1	0	0	10%	21%	25%
0	4%	9%	10%	23%	25%
+1	37%	36%	40%	11%	9%
+2 or better	59%	55%	40%	32%	12%
n	27	11	10	62	67

Conclusion: During their first year of life, most infants show surprisingly good leg function following minimally-invasive fetoscopic patch coverage of spina bifida aperta. Yet significant deterioration of leg function over the first year of life occurs in some. Data at 30-month follow-up will have to determine, how the fetoscopic Gießen group compares to the MOMS-trial patient groups in the long term. This information is important for counselling.