The purpose of this study was to assess the effect of obesity on flap and donor-site complications in patients undergoing free transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction. All patients undergoing breast reconstruction with free TRAM flaps at our institution from February 1, 1989, through May 31, 1998, were reviewed. Patients were divided into three groups based on their body mass index: normal (body mass index <25), overweight (body mass index 25 to 29), obese (body mass index > or =30). Flap and donor-site complications in the three groups were compared. A total of 936 breast reconstructions with free TRAM flaps were performed in 718 patients. There were 442 (61.6 percent) normal-weight, 212 (29.5 percent) overweight, and 64 (8.9 percent) obese patients. Flap complications occurred in 222 of 936 flaps (23.7 percent). Compared with normal-weight patients, obese patients had a significantly higher rate of overall flap complications (39.1 versus 20.4 percent; p = 0.001), total flap loss (3.2 versus 0 percent; p = 0.001), flap seroma (10.9 versus 3.2 percent; p = 0.004), and mastectomy flap necrosis (21.9 versus 6.6 percent; p = 0.001). Similarly, overweight patients had a significantly higher rate of overall flap complications (27.8 versus 20.4 percent; p = 0.033), total flap loss (1.9 versus 0 percent p = 0.004), flap hematoma (0 versus 3.2 percent; p = 0.007), and mastectomy flap necrosis (15.1 versus 6.6 percent; p = 0.001) compared with normal-weight patients. Donor-site complications occurred in 106 of 718 patients (14.8 percent). Compared with normal-weight patients, obese patients had a significantly higher rate of overall donor-site complications (23.4 versus 11.1 percent; p = 0.005), infection (4.7 versus 0.5 percent; p = 0.016), seroma (9.4 versus 0.9 percent; p <0.001), and hernia (6.3 versus 1.6 percent; p = 0.039). Similarly, overweight patients had a significantly higher rate of overall donor-site complications (19.8 versus 11.1 percent; p = 0.003), infection (2.4 versus 0.5 percent; p = 0.039), bulge (5.2 versus 1.8 percent; p = 0.016), and hernia (4.3 versus 1.6 percent; p = 0.039) compared with normal-weight patients. There were no significant differences in age distribution, smoking history, or comorbid conditions among the three groups of patients. Obese patients, however, had a significantly higher incidence of preoperative radiotherapy and preoperative chemotherapy than did patients in the other two groups. A total of 23.4 percent of obese patients had preoperative radiation therapy compared with 12.3 percent of overweight patients and 12.4 percent of normal-weight patients; 34.4 percent of obese patients had preoperative chemotherapy compared with 24.5 percent of overweight patients and 17.7 percent of normal-weight patients. Multiple logistic regression analysis was used to determine the risk factors for flap and donor-site complications while simultaneously controlling for potential confounding factors, including the incidence of preoperative chemotherapy and r...

The resource cost (cost to our hospital) of providing mastectomy plus breast reconstruction was calculated for 276 patients who had received both mastectomy and breast reconstruction at our institution. All patients had completed the entire reconstructive process, including reconstruction of the nipple. The resource costs of providing mastectomy with immediate breast reconstruction were compared with those of mastectomy with subsequent delayed reconstruction. We found that the mean resource cost for the 57 patients who had separate mastectomy followed by delayed breast reconstruction ($28,843) was 62 percent higher than that of mastectomy with immediate reconstruction ($17,801; n = 219, p < 0.001). Similar differences were found when patients were subgrouped by type of reconstruction (TRAM versus tissue expansion and implants), by laterality (unilateral versus bilateral), and by history of preoperative irradiation. We conclude that mastectomy with immediate breast reconstruction is significantly less expensive than mastectomy followed by delayed reconstruction and can potentially conserve resources.

One purported advantage of the free transverse rectus abdominis musculocutaneous (TRAM) flap for breast reconstruction is that, compared with the conventional TRAM flap, it has a better blood supply and therefore a lower incidence of fat necrosis. We tested this claim by reviewing the incidence of fat necrosis, both clinically and mammographically, in a group of 110 patients with 116 TRAM flap breast reconstructions who had undergone mammography of their reconstructed breasts. Of the 49 breasts reconstructed with free TRAM flaps, 4 (8.2 percent) had clinically evident fat necrosis, and 1 (2.0 percent) had fat necrosis that was detectable by mammography. Of the 67 breasts reconstructed with conventional TRAM flaps, 18 (26.9 percent) had clinically detectable fat necrosis, and 9 (13.4 percent) had fat necrosis that was detectable mammographically. Both of these differences were statistically significant (p = 0.0113 for clinical fat necrosis; p = 0.031 for mammographic fat necrosis). Fat necrosis was more common in patients who were obese or had a history of smoking, but neither association was statistically significant. We conclude that the use of the free TRAM flap reduces the incidence of fat necrosis in the reconstructed breast.

A series of 178 immediate reconstructions with regional or distant tissue for repair of oropharyngeal defects caused by treatment of head and neck cancer was reviewed to determine whether reconstruction with free flaps was more or less expensive than reconstruction with regional myocutaneous flaps. In this series, three types of flaps were used: the radial forearm free flap (n = 89), the rectus abdominis free flap (n = 56), and the pectoralis major myocutaneous flap (n = 33). Resource costs were determined by adding all costs to the institution of providing each service studied using salaried employees (including physicians). The two free-flap groups were combined to compare free flaps with the pectoralis major myocutaneous flap, a regional myocutaneous flap. Failure rates in the two groups were similar (3.0 percent for pectoralis major myocutaneous flap, 3.4 percent for free flaps). The mean costs of surgery were slightly higher for the free flaps, but the subsequent hospital stay costs were lower. Therefore, the total mean resource cost for the free-flap group ($28,460) was lower than the cost for the myocutaneous flap group ($40,992). The pectoralis major myocutaneous flap may have been selected for more patients with advanced disease and systemic medical problems, contributing to longer hospitalization and added cost. Nevertheless, this study suggests that free flaps are not more expensive than other methods and may provide cost savings for selected patients.

Answers to the question, "Does previous irradiation of a recipient site interfere with reconstruction by free-tissue transfer?" have been elusive. In an attempt to address that question, all free-flap procedures performed for reconstruction of the breast or of head and neck defects at the University of Texas M. D. Anderson Cancer Center between May 1, 1988 and February 15, 1996 were reviewed. The effects of prior irradiation of the recipient site on the incidence of total flap loss, partial flap loss, and thrombosis were assessed. During the study period, 1384 eligible free-flap reconstructions were performed. Total flap loss and partial flap loss were more common in the 428 flaps transferred to previously irradiated sites than in the patients without previous irradiation, but multiple logistic regression analysis showed that these differences were due to confounding factors. The authors conclude that previous irradiation of flap recipient sites does not statistically significantly affect the rate of partial or total free-flap loss.

No abstract

The measurement of engine cylinder joint surface holes is directly related to the control of product quality and the follow-up assembly. CMM is widely used in this field but can not meet the inspection requirements of automation, rapidity and Online testing. In this paper, a new measurement scheme based on the combination of multi-vision sensors is proposed. The global calibration method is focused on and a new dedicated calibration target is designed. The whole process of the system global calibration can be accomplished quickly through single imaging. The experiment results show that the method is feasible and with high precision. The method mentioned above can satisfy the engine production line requirements of intelligence, rapidity, high precision and low cost.

A method for analyzing the textural features of image is put forward by using the wavelet decomposition. That is used to measure color difference of ceramic tiles on-line. A linear array color CCD camera is used to grab the image of ceramic tiles, and then the image is pretreated. Two level wavelet decomposition is used on the ceramic tile image, and the energy feature of each sub-graph is extracted. The energy feature will be used as a feature matrix,and it can be carried out the classfication according to minimum distance classifier. It can reflect spatial relationship of color more effectively, when contrast with the color histogram, which is used as a traditional method. Experiments show that it is effective using wavelet analysis on image processing,and the sort results are approximately in accordance with the artificial detection.