A new simple method to measure the severity of pectus excavatum

SummaryBackgroundIn order to facilitate measurement and reduce radiation exposure, we developed a simple method to replace the Haller method for evaluating the severity of pectus excavatum (PE).MethodsWe retrospectively reviewed medical records of patients diagnosed with PE (ICD9 code 754.81) from April 2005 to November 2010 at Tri-service General Hospital, Taipei, Taiwan. The patients were divided into two groups: an adult group (>20 years old) and a pediatric group (≤20 years old). The sternum index (SI) was calculated according to the anterioposterior diameter of the chest cavity, from the sternum to the spine, divided by the patient’s height (SI = anterioposterior diameter of the chest cavity/the patient’s height × 100). We compared these values with the Haller index (HI = the transverse diameter of the chest cavity/the anterioposterior diameter) using coefficients of variation, Pearson’s correlation, and multiple linear regression analyses.ResultsA total of 109 patients (97 males and 12 females) who underwent the Nuss procedure for correction of PE were included in the study. Both groups showed a smaller coefficient of variation for the preoperative SI than that of the HI, Pearson’s correlation showed a good relationship between the HI and the preoperative SI, and multiple linear regression analyses revealed that the preoperative SI was a good predictor of the HI.ConclusionThe preoperative SI could serve as an alternative to the HI for evaluating the severity of PE, as well as the efficacy of surgery, without exposure of the patient to excessive radiation.