OBJECTIVE: To provide experimental basis for improving the curative effect of pectus excavatum. METHODS: Twelve rabbits were adopted in this experiment. After the bilateral second and third costal cartilages of the rabbits were resected subperichondrially, their right second and third costal perichondriums were damaged intentionally. Then, the bilateral third costal perichondriums were stitched into a tube-like structure and the second ones were left opened. After 2, 4, 6 of operation, the bilateral second and third neocartilages were measured for their width, and histological character were observed under microscope. RESULTS: 1. After 2, 4, 6 months of operation, the average width of the bilateral second neocartilages were significantly greater than the preoperative ones. 2. 4 and 6 months after operations, there was no significant difference in the average width of the bilateral third neocartilages and the preoperative ones. 3. The amount, distribution of costal neocartilage cells and the arrangement of costal neocartilage matrix within the left second and third costal cartilages were better than the right under the light microscope. 4. The left third costal neocartilage was regenerated and remodeled better than all the others. CONCLUSION: The integrality of costal perichondrium is in favor of the regeneration of costal cartilage, and the sleeve stitch of costal perichondrium facilitates the remodeling of costal neocartilage.
ObjectiveTo investigate the accuracy of multi-slice spiral CT (MSCT) scan and image reconstruction technology for measuring morphological parameters of costal cartilages and to evaluate the volume of costal cartilages. MethodsBetween March and August 2013, 75 patients with congenital microtia and scheduled for auricle reconstruction were included in the study. Of 75 patients, there were 49 males and 26 females with a mean age of 8 years and 5 months (range, 5 years and 7 months to 32 years and 7 months) and a mean weight of 29.5 kg (range, 21-82 kg). A Philips Brilliance 64 MSCT machine was used to scan 1st-12th costal cartilages with the parameters based on the age and weight of the patients. All the data were transported to the workstation for reconstructing the image of the costal cartilages with the technique of maximum intensity projection (MIP) and volume rendering technique (VRT). Then the morphologies of costal cartilages were observed through the images on VRT; the width of the costal cartilaginous ends close to ribs (W) and the length of the total cartilage (L) were measured and compared with their counterparts (W' and L') after the costal cartilages were harvested during the processes of auricle reconstructions to analyze consistency between these two sets of data. ResultsThe morphologies of ribs and costal cartilages shown on VRT image got fine sharpness, verisimilitude, and stereoscopic impressions. A total of 192 costal cartilages were examined. The results showed that the widths of the costal cartilaginous ends close to ribs (W) was (9.69±1.67) mm, and W' was (9.73±1.64) mm, showing no significant difference between W and W' (t=-1.800, P=0.073), and interclass correlation coefficient (ICC) test showed Cronbach's α=0.993. The length of the total cartilage (L) was (83.03±23.86) mm, and L' was (81.83±16.43) mm, showing no significant difference between L and L' (t=1.367, P=0.173), and ICC test showed Cronbach's α=0.904. Linear-regression analysis showed L=1.28×L'-21.93 (R2=0.780, F=673.427, P=0.000). The results suggested there was a good consistency between these two sets of data. ConclusionScanning costal cartilages with appropriate parameters and reconstructing the cartilaginous image with MIP is an effective method to measure the width and length of costal cartilage and to estimate costal cartilage volume, which can provide accurate reference for plastic surgery together with reading the morphology from the image on VRT.
ObjectiveTo explore the effect of the expanded capsule on the growth of autogenous costal cartilage. MethodsSixteen New Zealand white rabbits at the age of 3 months (weighing, 2.2-2.5 kg; male or female) were selected and four 15 mL tissue expanders were implanted on the back symmetrically. After 1 month, the expanded capsule formed, the tissue expanders were removed; the capsule of the left side was removed (experimental group), and the capsule of the right side was reserved (control group); meanwhile, the right 7th and 8th costal cartilage without the perichondrium was divided into segments and placed into the capsule of 2 groups symmetrically. At 4 and 8 weeks after transplantation, the cartilage was harvested for the general, weighing, and histological observations. ResultsOne rabbit died during the experiment, and the other 15 rabbits survived. The differences of cartilage weight between before and after transplantation showed more obvious increase in the experimental group[(0.003 4±0.002 7) g and (0.005 8±0.001 4) g] than those in the control group[(-0.000 3±0.001 9) g and (-0.003 9±0.005 3) g] at 4 and 8 weeks, showing significant differences between 2 gouprs (t=4.331, P=0.029; t=6.688, P=0.008). The change of cartilage weight at 8 weeks was significantly higher than that at 4 weeks in the experimental group (t=-3.098, P=0.001); but the change of cartilage weight at 8 weeks was significantly lower than that at 4 weeks in the control group (t=2.491, P=0.009). The histological observation showed that the activity of the cartilage was enhanced in 2 groups at 4 and 8 weeks when compared with normal cartilage, and more obvious change was observed in the experimental group than in the control group. And the acellular area was seen in the cartilage at 8 weeks in the control group. The Masson staining results showed that the color was deeper in the experimental group than in the control group. ConclusionThe removal of the expanded capsule during operation is beneficial to the growth of autogenous costal cartilage. The results can provide corresponding experimental guidance for the clinical problems.