Pulmonary fibrosis (PF) is a lung disease in which lung tissue becomes damaged and scarred. Common symptoms of PF include shortness of breath, dry cough, fatigue, weight loss, and aching in muscles and joints.

HRCT scan

A high-resolution computed tomography (HRCT) scan is an important tool to evaluate IPF.

Several abnormalities can be observed using this method: ground-glass opacities, consolidation, reticulation, and honeycombing. The extent of fibrosis may also be measured by evaluating the combination of reticulation and honeycombing.

According to a 2005 research paper, the improved scanner resolution in HRCT delivered additional information regarding the “distribution and types of opacities and other abnormalities identified in chronic interstitial diseases.”

The authors stated that while surgical lung biopsy is considered the standard for diagnosis of usual interstitial pneumonia (UIP), “when typical clinical and high-resolution HRCT features are present and assessed by expert clinicians and radiologists, the features may allow a confident diagnosis in more than 50 percent of cases and eliminate the need for surgical lung biopsy.”

It has been confirmed that the fibrosis score – the combination of the severity of reticulation and honeycombing – and the Dclo, a test used to measure carbon monoxide diffusion capacity, are two of the most accurate predictors of mortality, as tested by Lynch and his team in a 2005 study.

The same study also addressed the lack of standardized HRCT images that could potentially show the common features of interstitial lung diseases. This problem emerged in the study, since there was poor agreement among radiologists regarding the presence or absence of honeycombing, one of the main features for diagnosing IPF.

It has been suggested that a surgical biopsy may not be necessary in patients that exhibit common features such as reticulation and honeycombing, both essential to the diagnosis of IPF, instead using an HRCT scan and the evaluation of the findings by experienced radiologists.

A 2012 study also found that “radiologic evidence of pulmonary fibrosis may even precede symptoms.” Therefore, an HRCT scan may be an important tool to diagnose PF before symptoms such as honeycombing and increased reticulation appear, given that “progression of asymptomatic to symptomatic pulmonary fibrosis may occur over a period of years to decades,” according to the study.