title: Estimation of total lung capacity by planimetry of chest radiographs in children 5 to 10 years of age.
abstract: Planimetry is an inexpensive, easy method to estimate total lung capacity (TLC) when radiographs are available. This prospective study was done to see which of the published planimetric methods for estimating TLC in children aged 5 to 10 yr was best. Helium dilution TLC measurements and 6-foot posteroanterior (PA) and lateral chest films at maximum inspiration were performed on 10 normal subjects and 14 subjects with chest abnormalities. The 2 lung areas on the PA (areas A and B) and lateral (area C) chest films were measured by planimetry. Results of helium dilution TLC measurements were compared to calculations of three different published equations to obtain the correlation coefficient (r) and the probability of identity (P). The equation TLC = 0.67 (A+B+C) ml had the best r (0.94) and P value (0.96). Thus, TLC can be estimated by planimetry in this age group.
mesh_terms: D000886:Anthropometry; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007201:Indicator Dilution Techniques; D008168:Lung / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008176:Lung Volume Measurements; D008297:Male; D011859:Radiography; D014109:Total Lung Capacity