Interestingly, the present study identified PMF in 25
sandblasters (92%) and only 7 stone carvers (43.7%). Simi-
larly, Antao et al.29 found PMF in 39.1% of stone carvers.
Unlike our results, Alper et al.1 observed PMF in half
of the cases of silicosis in denim sandblasters. Although
both studies showed similar latency periods (median 84
vs. mean 82 months), the exposure durations, ages of the
workers, and criteria for the diagnosis of PMF on HRCT
were different; this makes it difficult to reach a conclu-
sion about the different frequencies of PMF between the
two studies. Despite these considerations, the identifica-
tion of PMF is important because it is the replacement of
aerated lung tissue with a mass of non-functional fibrous