[New method of scoring lung changes using computed tomography in patients with cystic fibrosis]

1. Introducing our own modification of the scoring system in high resolution computed tomography (HRCT) to evaluate changes in the lungs of patients with cystic fibrosis. 2. Comparison between scoring systems based on conventional chest radiography and HRCT in our own modification.

The material consists of 50 children: 28 girls and 22 boys aged 5-17 years. Chest X-rays in P-A projection and HRCT (Picker PQS) were performed in all the children. Chest X-rays were evaluated using the Brasfield and Northern scores. In the Brasfield scoring system both lungs are assessed together. The Northern scoring system assesses each lung separately. In our own modification of the HRCT scoring system each lung was divided into six parts. Bronchiectases, bronchial wall thickness, mucous plugs, atelectases, emphysema, cysts and mosaic perfusion were assessed in each part of the lungs.

The analysis using the Brasfield score showed: minimal changes in 9 patients (18%; grading scale 20-24 points), mild changes in 23 (46%; 15-19 points), acute findings in 18 (36%; 7-14 points). The analysis using the Northern score showed: no changes in 1 patient (2%; grading scale 0 points), pathological findings were seen in the right lung in 49 patients (98%), while in the left lung in 48 (96%). Pathological changes in both lungs were seen in 96% of the patients. HRCT exams were evaluated based on our own modification of Bhalla and Maffesanti scores. Bronchial wall thickening was seen in all the patients examined, bronchiectases in 40 (80%), atelectasis, emphysema, bullas in 34 (68%), mosaic perfusion in 20 (40%). Central mucous plugs were seen in 34 patients (68%), peripheral plugs in 40 (80%). Both central and peripheral mucous plugs were observed in 33 patients (66%). There were no mucous plugs in 9 children (18%). The extent of lung lesions was compared using the Brasfield score and the HRCT score in our own modification. There were no extensive changes in 8 patients (16%) on chest X-ray evaluated by Brasfield score and only in 1 patients (2%) on HRCT. Using the Northern score 1 patient was assessed as having normal lungs. In HRCT assessment there was no patient with normal lungs. There were no mucous plugs in 23 patients (46%) on chest X-ray evaluation. In HRCT mucous plugs were not found only in 9 patients (18%). 8 children had two HRCT exams in 1-6 year intervals. In all of them the progression of lung lesions was observed on HRCT. In conventional radiography the progression of the disease was seen in 3 patients evaluated in the Northern score and in 4 children evaluated using the Brasfield score.

1. Our own modification of the HRCT scoring system in patients with cystic fibrosis simplified the evaluation of the lung lesions and made it possible to adapt it to the practical needs of physiotherapists. The assessment of the central and peripheral mucous plugs is very important for planning individual physiotherapy for every child. 2. HRCT has an advantage over conventional chest X-rays in the evaluation of the stage and progression of lung disease in patients with cystic fibrosis. Plain films do not allow exact evaluation of the mucous plugs that obstruct the bronchial tree. 3. In spite of this advantage, due to the radiation dose involved in CT, one should carefully assess the indications to use this method in routine evaluation of the disease in children with cystic fibrosis.