Comparison of Follow-Up Length-Matched Single-Center Myelomeningocele Postnatal Closure Cohort to the Management of Myelomeningocele Study (MOMS) Trial Results

Abstract

<b><i>Objective:</i></b> We sought to compare our large single-institution cohort of postnatal myelomeningocele closure to the 2 arms of the Management of Myelomeningocele Study (MOMS) trial at the designated trial time points, as well as assess outcomes at long-term follow-up among our postnatal cohort. <b><i>Methods:</i></b> A single-institutional retrospective review of myelomeningocele cases presenting from 1995 to 2015 at Children’s Hospital of Pittsburgh was performed. We compared outcomes at 12 and 30 months to both arms of the MOMS trial and compared our cohort’s outcomes at those designated time points to our long-term outcomes. Univariate statistical analysis was performed as appropriate. <b><i>Results:</i></b> One-hundred sixty-three patients were included in this study. All patients had at least 2-year follow-up, with a mean follow-up of 10 years (range 2–20 years). There was no difference in the overall distribution of anatomic level of defect. Compared to our cohort, the prenatal cohort had a higher rate of tethering at 12 months of age, 8 versus 1.8%. Conversely, the Chiari II decompression rate was higher in our cohort (10.4 vs. 1.0%). At 30 months, the prenatal cohort had a higher rate of independent ambulation, but our cohort demonstrated the highest rate of ambulation with or without assistive devices among the 3 groups. When comparing our cohort at these early time points to our long-term follow-up data, our cohort’s ambulatory function decreased from 84 to 66%, and the rate of detethering surgery increased almost 10-fold. <b><i>Conclusions:</i></b> This study demonstrated that overall ambulation and anatomic-functional level were significantly better among our large postnatal cohort, as well as having significantly fewer complications to both fetus and mother, when compared to the postnatal cohort of the MOMS trial. Our finding that ambulatory ability declined significantly with age in this patient population is worrisome for the long-term outcomes of the MOMS cohorts, especially given the high rates of cord tethering at early ages within the prenatal cohort. These findings suggest that the perceived benefits of prenatal closure over postnatal closure may not be as substantial as presented in the original trial, with the durability of results still remaining a concern.

Myelomeningocele Surgery over the 10 Years Following the MOMS Trial: A Systematic Review of Outcomes in Prenatal versus Postnatal Surgical Repair

“…The remaining 112 were assessed for eligibility by full-text reading. The selection left us with 27 eligible articles that were included in the study ( Figure 1 ) [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ].…”

“…The average hydrocephalus rates were 45.65% in prenatal series [ 10 , 12 , 14 , 23 , 24 , 28 , 33 , 34 ] and 66.57% in those reporting a postnatal treatment [ 8 , 9 , 11 , 15 , 16 , 18 , 22 , 26 , 29 , 30 , 31 ]. The ability to walk seemed to be slightly higher in prenatal series (68.78%) [ 10 , 34 ] than in postnatal groups (60.24%) [ 8 , 16 , 22 , 30 , 31 , 32 ]. The urinary continence average rate was also higher in prenatal series (40.97%) [ 20 , 27 , 28 ], compared with postnatal studies (8.94%) [ 15 , 27 , 29 , 30 ].…”

“…Additional SBA recoverage average rates were 11.9% in prenatal series [ 14 , 23 , 25 ] and 7.93% in the postnatal groups [ 11 , 16 ]. Only one prenatal study reported a retethering rate of 2.81% [ 14 ] whereas the average retethering rate in postnatal studies was 11% [ 8 , 15 , 18 , 29 , 31 , 32 ]. A reversal of the hindbrain herniation rates was higher in prenatal (63.14%) [ 12 , 13 , 23 , 24 , 25 , 28 , 33 ] than in postnatal groups (33.71%) [ 8 , 9 , 13 , 15 , 16 , 23 , 31 ].…”

“…The results of the MOMS trial are clearly encouraging [ 4 , 41 ] but historically they have to be considered as early experience with fetal surgery. Research on the in utero repair of spina bifida continues and several fetal medicine centers have published their ‘post-MOMS’ experience on fetal surgery for spina bifida [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. More importantly, the postnatal repair of spina bifida carries on, for several obvious reasons, in many pediatric neurosurgery centers and yields good results [ 42 ].…”

“…In our study, 50% of the articles still reported a postnatal closure of the defect in cases of myelomeningocele. One of the latest studies included in our analysis [ 32 ] challenged the idea that the results of a prenatal repair of SB are significantly better than those of a postnatal repair. The study showed that the tethering of the spinal cord occurs at a higher rate in prenatally-treated patients than in postnatally-treated patients [ 32 ].…”