Analysis of Scar Tissue Distribution on Rat Palates: A Laser Doppler Flowmetric Study

Blood flow distribution of repaired lip in cleft lip patients

OBJECTIVE

To investigate the blood flow distribution in the repaired lip of cleft patients using a laser Doppler imager and to evaluate the difference in blood flow of the scar tissue between unilateral cleft lip patients with and without cleft palate.

MATERIALS AND METHODS

Twenty patients with either unilateral cleft lip only (CL group, n = 8) or cleft lip and palate (CLP group, n = 12) were used as subjects. The blood flow of the upper lip was two-dimensionally visualized by a color scale alongside the corresponding photo image of the tissue surface with laser Doppler imaging. The upper lip photo image was divided into five regions: scar, white lip on the cleft side, white lip on the noncleft side, red lip on the cleft side, and red lip on the noncleft side. The average flux score (AFS), which is proportional to blood flow, was analyzed in each region.

RESULTS

The AFS for the scar region was significantly (P < .05) lower than in the other four regions. The AFS for the red lip on the cleft side was not significantly different from that for the noncleft side. The white lip revealed a significantly (P < .05) higher score on the cleft side than on the noncleft side. The AFS ratio (AFS in the scar region/AFS in the white lip region) was significantly (P < .01) lower in the CLP group than in the CL group.

CONCLUSIONS

These results suggest that blood flow distribution in the repaired lip might be affected by the anatomic features of the cleft.

Role of secreted frizzled-related protein 1 (SFRP1) in wound healing

Wound healing is a complex cascade of events, which diminishes the size of the wound and reestablishes tissue integrity. Secreted frizzled-related protein 1 (SFRP1) contributes to the inhibition of apoptosis in fibroblast populations. We investigated the role of SFRP1 in a mouse wound-healing model; 2.0-mm excisional wounds were created in the scalp and hard palate. Healing responses were measured by histomorphometric analysis, apoptosis assay, and immunohistochemistry. Dermal wounds did not harbor SFRP1, but healed faster than palatal wounds which expressed significant levels of SFRP1. Antibody experiments aimed at blocking SFRP1 in palatal wounds resulted in promotion of wound closure, enhancement of new tissue formation, decrease of inflammatory cell infiltrate, and increase of apoptotic fibroblasts. Analysis of the present data suggests that SFRP1 may be partly responsible for the poorer healing performance of the palatal wounds compared with dermal wounds. Blocking SFRP1 results in improvement of palatal healing outcomes.