Comparative osseous and soft tissue morphology following cleft lip repair

To quantify comparative improvement between osseous and soft tissue asymmetry following primary lip repair.

Retrospective analysis of preoperative and postoperative computed tomography scans of infants with unilateral cleft lip and palate. Sixteen soft tissue landmarks were placed using an exploratory two-/three-dimensional image processing system and compared for asymmetry.

Computed tomography scans were obtained on 26 patients (13 boys, 13 girls) of Chinese ethnicity (mean age = 0.25 years) prior to Millard lip repair. Nineteen of these contributed to follow-up comparative studies prior to palatoplasty at a mean age of 0.92 years. There were 18 left-sided and eight right-sided clefts.

Euclidean distance matrix asymmetry analysis was used to determine the amount of soft tissue asymmetry pre- and postlip repair. Similar analyses of the same scans were performed for 41 osseous landmarks.

Soft tissue landmarks had 36/39 (92%) preoperative and 13/39 (33%) postoperative asymmetric pairs. Osseous distances demonstrated 77/125 (61%) asymmetric pairs preoperatively and 60/125 (48%) postoperatively. Soft tissue and osseous distances of the lip region demonstrated 32% and 39% postoperative asymmetry, respectively. Soft tissue and osseous distances of the nasal region demonstrated 52% and 72% postoperative asymmetry, respectively. Soft tissue and osseous distances of the facial landmarks demonstrated 24% and 34% postoperative asymmetry, respectively.

Primary lip repair appears to effect gains in symmetry in soft tissue and provides sufficient molding forces to cause correlating symmetry changes in underlying osseous structures.