In this study, we assessed the validity of a subjective histological-histochemical scoring system as compared to an automated histomorphometry program for analyzing cartilage repair tissue. In the first part of the study, we assessed the ability of the human eye to estimate the percent cartilage in a histological section. Twenty-nine rabbit periosteal explants that had been cultured in agarose transforming growth factor-beta (TGF-beta) were selected so that the percentage of cartilage in the specimens was distributed equally from 0% to 100%. Color photomicrographs were evaluated by 5 expert observers who gave a visual estimate of the percent cartilage. There was a strong correlation between the estimated and actual percent cartilage (R(2) = 0.92, p < 0.0001) and among the observers (I.C.C. = 0.89). On average, the estimated percent cartilage was within ten percent of the actual percent measured. In the second part, we compared the data derived using a simple cartilage score with those obtained by automated image analysis. The histological slides from 159 explants cultured under various experimental conditions (14 treatment groups) in two different experiments were analyzed. The cartilage content was estimated visually and a score from 0 to 3 was assigned. A previously validated, computerized image analysis system was used to measure the actual percent cartilage. Statistical analyses revealed a good linear regression (R(2) = 0.84, p = 0.0001), and even better polynomial correlation between the actual measurement and the score (R(2) = 0.88, p = 0.0001). These data demonstrate the validity of a simple histological-histochemical subjective scoring system. A computerized automated program such as the one employed in this study is preferable due to its many advantages. However, a subjective scoring system may be appropriate to use when the funding and expertise required for a computerized image analysis program are not available.

Postoperative pulmonary complications (PPCs) after esophagectomy have been reported to occur in 15.9-30% of patients and lead to increased postoperative morbidity and mortality, prolonged duration of hospital stay, and additional medical costs. The purpose of this retrospective cohort study was to investigate the possible prevention of PPCs by intensive preoperative respiratory rehabilitation in esophageal cancer patients who underwent esophagectomy. The subjects included 100 patients (87 males and 13 females with mean age 66.5 ± 8.6 years) who underwent esophagectomy. They were divided into two groups: 63 patients (53 males and 10 females with mean age 67.4 ± 9.0 years) in the preoperative rehabilitation (PR) group and 37 patients (34 males and 3 females with mean age 65.0 ± 7.8 years) in the non-PR (NPR) group. The PR group received sufficient preoperative respiratory rehabilitation for >7 days, and the NPR group insufficiently received preoperative respiratory rehabilitation or none at all. The results of the logistic regression analysis and multivariate analysis to correct for all considerable confounding factors revealed the rates of PPCs of 6.4% and 24.3% in the PR group and NPR group, respectively. The PR group demonstrated a significantly less incidence rate of PPCs than the NPR group (odds ratio: 0.14, 95% confidential interval: 0.02~0.64). [Correction added after online publication 25 June 2012: confidence interval has been changed from -1.86~ -0.22] This study showed that the intensive preoperative respiratory rehabilitation reduced PPCs in esophageal cancer patients who underwent esophagectomy.