Modification of the Fetal Profile Line to Measure Reversal of Forehead Slope after Early Repair of Frontoethmoidal Encephalocele.

Abstract

Objective Congenital frontoethmoidal encephaloceles are associated with a shallow sloping forehead. We (1) sought to determine if early repair reverses abnormal forehead slope, and (2) assessed a modification of the fetal profile (FP) line to assess results. Design Study of two cases. Participants Newborns with frontoethmoidal encephaloceles repaired prior to the age of 4 months with cranial base bone grafting. Main Outcome Measures Forehead slope was assessed using a modification of the FP line, defined as the line that passes through the anterior border of the mandible and nasion, on pre and postoperative magnetic resonance imaging (MRI) in the midsagittal plane. A modified FP (mFP) line anterior to the forehead was " - ", while a posterior (normal) mFP line was " + ." The largest distance from the mFP line to the forehead was measured. Results Both infants underwent bifrontal craniotomy, excision of encephalocele, and repair of cribriform plate defect using full-thickness autologous parietal bone before the age of 4 months. Preoperatively, the mFP line was -20.6 mm in case 1, and -9.8 mm in case 2. In both cases, follow-up MRI showed excellent reversal of forehead slope and normal calvarium development. The mFP line improved to +7.4 (age = 16 months) in case 1, and +7.6 (age = 11 months) in case 2. The parietal bone donor site ossified completely within 3 months in both cases. Conclusion Early repair with bone grafting can promote normal frontal bone development and improve forehead slope. The mFP line is a useful method to measure degree of forehead slope.