Histological comparison of the alar nasal cartilages in unilateral cleft lip.
Patients with unilateral cleft lip display characteristic nasal changes that are independent of the degree of deformity. Defenders of the intrinsic theory consider these deformities to be due to embryogenic alterations of the alar nasal cartilages. Those that propose the extrinsic theory defend the thesis that the deformity is due to disorganization of the perioral muscles deformed by the cleft. The purpose of this study is to contribute histological evidence to help clarify the issue.


METHODS
Specimens of the lateral portion of both the healthy and the cleft side of the alar cartilages were obtained from 18 patients. These uniformly cut specimens were stained by hematoxylin and eosin. Samples from 2 patients were excluded due to imperfections. The same pathologist examined all the slides. He was unaware of the origins of the specimens; he counted the number of chondrocytes and quantified the cartilage matrixes.


RESULTS
All data was analyzed statistically, and no significant statistical differences were apparent, either in the number of chondrocytes or the cartilage matrix between the healthy side and the cleft side.


CONCLUSIONS
These results apparently support the group that defend the extrinsic theory; nevertheless, the doubt about the composition of the cartilage matrix remains, not only concerning the glycosaminoglycans that compose them, but also regarding elastin and collagen and its linkages that can cause different degrees of collagen consistency.
Modolin
Miguel
M
Division of Plastic Surgery, Hospital das Clínicas, Faculty of Medicine, University of São Paulo.
Baracat
Glaucia Zeferino
GZ
Kamakura
Luiz
L
Cintra
Wilson
W
Cruz
Luiz Gustavo Balaguer
LG
Ferreira
Marcos Castro
MC
D002356:Cartilage / Q000166:cytology*; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D019902:Chondrocytes; D002971:Cleft Lip / Q000473:pathology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009666:Nose / Q000002:abnormalities / Q000033:anatomy & histology*