BACKGROUND AND PURPOSE:

• Zarutskie et al. (Ultrasound in Obstetrics & Gynecology, 2019) examined if prenatal brain imagining in fetuses that underwent prenatal NTD repair could predict the need for postnatal hydrocephalus treatment

METHODS:

• Retrospective study
  • Fetuses who underwent prenatal in-utero myelomeningocele repair
• Timing of data collection
  • Presurgery ultrasound
  • Presurgery MRI
  • 6-week postsurgery MRI
  • Predelivery ultrasound
• Independent variables collected
  • Gestational age
  • Head circumference
  • Mean ventricular width
  • Ventricular volume (MRI only)
  • Hindbrain herniation (HBH) score (MRI only)
  • Level of lesion (LOL) defined as the upper bony spinal defect (presurgery ultrasound only)
• Additional variables were calculated based on measurements
  • Change in degrees of HBH
  • Ventricular width growth (mm/week)
  • Ventricular volume growth (mL/week)
• Pediatric neurosurgeon determined need for hydrocephalus treatment based on standard of care
  • ventriculoperitoneal shunt or endoscopic third ventriculostomy with choroid plexus cauterization
• Predictive value assessed using
  • ROC curves
  • Logistic regression analyses

RESULTS:

• 50 fetuses included
  • 32 open hysterectomy | 18 fetoscopic repair
  • 2 neonates in fetoscopic group died and were therefore not included in final analysis
• Mean gestational age
  • Presurgery ultrasound: 21.8 weeks
  • Presurgery MRI: 22.0 weeks
  • Postsurgery MRI: 30.4 weeks
  • Predelivery ultrasound 31.0 weeks
• 16 subjects required hydrocephalus treatment
• Strongest individual predictor for HT: Degree of HBH on postsurgery MRI
  • HBH score on postsurgery MRI: AUC 0.86 (P <0.01)
  • MRI ventricular volume growth: AUC 0.79 (P = 0.01)
  • Change in HBH: AUC 0.82 (P = 0.01)
  • Postsurgery MRI ventricular volume: AUC 0.73 (P = 0.03)
  • Mean ventricular width on predelivery ultrasound (0.73; P = 0.01)
• Other variables had lower AUCs < 0.7
• Combining studies improved accuracy with the best prediction when using
  • Ventricular volume growth ≥2.02 mL/week and/or HBH of 3 on postsurgery MRI
  • Odds ratio (OR) 42 (95% CI, 4–431; accuracy 84%)
• Another strong predictor (following logistic regression)
  • Persistence of severe HBH 6 weeks after surgery (MRI)
  • OR 39 (95% CI, 4–369; accuracy 84%)
• Similar results using MOMS trial criteria for hydrocephalus treatment

CONCLUSION:

• The most accurate predictor of the need for postnatal HT
  • Significant growth (> 2.02 mL/week) in ventricular volume
  • 6-week postsurgery MRI with HBH score of 3 and lack of reversal of HBH
  • Mean ventricular width ≥ 15 mm on presurgery ultrasound
• Many baseline measurements (e.g., degree of HBH) prior to surgery were poor predictors
• The authors also conclude that aside from predictive value and counseling aid, the results of this study support the hypothesis that HBH is a significant driver of hydrocephalus in these patients

Learn more – Primary Sources:

Prenatal brain imaging for predicting need for postnatal hydrocephalus treatment in fetuses that had neural tube defect repair in utero

Related ObG Topics:

NICHD Study Update: Does Prenatal Surgery of Myelomeningocele Improve Motor Development Beyond 2 Years Follow-Up?

Prenatal vs Postnatal Spina Bifida Repair and the Impact on Neurodevelopmental Impairment

Neural Tube Defects: Definitions, Key Clinical Findings and Management