Abstract
Purpose
This study was undertaken to assess the presence and extent of air trapping (AT) on high-resolution computed tomography (HRCT) in patients with Wegener’s granulomatosis (WG) and to correlate the finding with the inspiratory pattern and bronchial/bronchiolar involvement.
Materials and methods
Twenty-one patients (7 M/14 F) with WG underwent inspiratory and expiratory HRCT. Images were evaluated for the presence and extent of AT and for airway involvement (bronchi/bronchioles); the predominant HRCT pattern was also documented. The attenuation difference was measured between the areas of AT on expiration and the same areas on inspiration in order to verify the finding of AT. The extent of AT was calculated by visual scoring and correlated with the predominant inspiratory patterns and bronchial/bronchiolar involvement.
Results
AT was found in seven patients (33.3%) and its extent ranged between 3% and 70% (mean 15.8±7). Two patients showed no lesions on inspiratory HRCT, and the only finding was AT on expiration. The attenuation difference between areas of AT on expiration and the same areas on inspiration ranged between 32 and 89 HU. Inspiratory HRCT was pathological in 19 patients (90.4%), and the principal lung patterns were nodular, cavitary or noncavitary (n=7, 38.9%); ground-glass opacities (n=5, 26.3%); masses (n=3, 15.8%); fibrotic (n=3, 15.8%); and consolidation with air bronchogram (n=1, 5.3%). Bronchial and bronchiolar involvement was found in 14 and five patients, respectively. No statistically significant correlation was found between AT extent and the findings on inspiration. In addition, there were no specific patterns that caused higher or lower scores of AT. Moreover, when bronchial or bronchiolar involvement was absent, the mean AT score was statistically significantly higher.
Conclusions
Areas of AT represent a new and indirect HRCT finding, — and in rare cases the only finding — of pulmonary WG. The nonsignificant correlation between AT extent and inspiratory findings may suggest AT as an additional HRCT finding in patients with WG.
Riassunto
Obiettivo
Scopo di questo studio è quello di valutare la presenza e l’estensione dell’intrappolamento d’aria nella granulomatosi di Wegener (GW) attraverso l’utilizzo della tomografia computerizzata ad alta risoluzione (HRCT) e correlare con i reperti inspiratori ed il coinvolgimento bronchiale/bronchiolare.
Materiali e metodi
21 pazienti (7M/14F) affetti da WG sono stati esaminati con HRCT in fase inspiratoria ed espiratoria. Le immagini sono state valutate per la presenza e l’estensione di intrappolamento d’aria, per il coinvolgimento delle vie aeree (bronchi/bronchioli) ed il modello HRCT dominante. È stata misurata la differenza di attenuazione tra le regioni di intrappolamento d’aria e le corrispondenti regioni in inspirazione per poter verificare la presenza di intrappolamento d’aria. L’estensione di intrappolamento d’aria è stata calcolata con calcolo visuale (visual scoring) e correlata con il modello inspiratorio dominante e il coinvolgimento bronchiale/bronchiolare.
Risultati
L’intrappolamento d’aria è stato identificato in 7 (33,3%) e la sua estensione era tra il 3% ed il 70% (15,8±7). Due dei pazienti non avevano presentato dei reperti in fase inspiratoria ed il loro unico reperto era l’intrappolamento d’aria in fase espiratoria. La differenza di attenuazione tra le regioni d’intrappolamento d’aria in espirazione e le stesse regioni in inspirazione aveva un range compreso tra 32 e 89 unità di Hounsfield (HU). La TC ad alta risoluzione era patologica in 19 pazienti (90,4%) e rappresentata dai seguenti modelli polmonari principali: nodulare, cavitario/non cavitario (n=7, 38,9%), opacità a vetro smerigliato (GGO) (n=5, 26,3%), masse (n=3, 15,8%), modello fibrotico (n=3, 15,8%) e consolidativo con broncogramma aereo (n=1, 5,3%). Il coinvolgimento dei bronchi e bronchioli è stato riscontrato in 14 e 5 pazienti rispettivamente. Non è stata rilevata una correlazione statisticamente significativa tra l’estensione dell’intrappolamento d’aria ed i reperti in fase inspiratoria. Inoltre, non ci sono dei modelli specifici che possono causare dei livelli alti o bassi d’intrappolamento d’aria. Per di più, quando il coinvolgimento bronchiale o bronchiolare è assente il valore medio dei livelli d’intrappolamento d’aria è statisticamente e significativamente più elevato.
Conclusioni
Le regioni d’intrappolamento d’aria nella granulomatosi di Wegener, rappresentano un nuovo reperto, indiretto e probabilmente, in rari casi, l’unico reperto di coinvolgimento polmonare rilevato in TC ad alta risoluzione. La correlazione non statisticamente significativa tra l’estensione dell’intrappolamento d’aria ed i reperti in fase inspiratoria possono suggerire l’intrappolamento d’aria come un ulteriore reperto nella TC ad alta risoluzione in pazienti con granulomatosi di Wegener.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References/Bibliografia
Reuter M, Schnabel A, Wesner F et al (1998) Pulmonary Wegener’s granulomatosis: correlation between high-resolution CT findings and clinical scoring of disease activity. Chest 114:500–506
Cordier J-F, Valeyre D, Guillevin L et al (1990) Pulmonary Wegener’s granulomatosis: a clinical and imaging study of 77 cases. Chest 97:906–912
Hoffman GS, Kerr GS, Leavitt RY et al (1992) Wegener granulomatosis: an analysis of 158 patients. Ann Intern Med 116:448–498
ATS/ ERS (2002) International multidisciplinary consensus classification of idiopathic interstitial pneumonias. Am J Respir Crit Care Med 165:277–304
Komocsi A, Reuter M, Heller M et al (2003) Active disease and residual damage in treated Wegener’s granulomatosis: an observational study using pulmonary high-resolution computed tomography. Eur Radiol 13:36–42
Leavitt RY, Fauci AS, Bloch DA et al (1990) The American College of Rheumatology criteria for the classification of Wegener’s granulomatosis. Arthritis Rheum 33:1101–1107
Jennette CJ, Falk RJ, Andrassi K et al (1994) Nomenclature of systemic vasculitides: proposal of an international consensus conference. Arthritis Rheum 37:187–192
Weibel ER, Taylor CR (1988) Design and structure of the human lung. In: Fishman AP (ed) Pulmonary diseases and disorders. McGraw-Hill, New York, pp 11–60
Naidich DP, Webb WR, Grenier PA et al (2005) In: Imaging of the airways: functional and radiologic correlations. Lippincott Williams & Wilkins, Philadelphia
Fraser RS, Muller NL, Colman N, Pare PD (1999) Bronchiectasis and other bronchial abnormalities. In: Fraser RS, Muller NL, Colman N, Pare PD (eds) Diagnosis of diseases of the chest, 4th edn. W.B. Saunders Company, Philadelphia, pp 2265–2297
Austin JHM, Muller NL, Friedman PJ et al (1996) Glossary of terms for CT of the lungs: recommendations of the Nomenclature Committee of the Fleischner Society. Radiology 200:327–331
Mastora I, Remy-Jardin M, Sobaszek A et al (2001) Thin-section CT finding in 250 volunteers: assessment of the relationship of CT findings with smoking history and pulmonary function test results. Radiology 218:695–702
Tanaka N, Matsumoto T, Miura G et al (2003) Air trapping at CT: high prevalence in asymptomatic subjects with normal pulmonary function. Radiology 227:776–785
Webb WR, Muller LN, Naidich PD (2009) In: High resolution CT of the lung, 4th edn. Lippincott Williams & Wilkins /Wolters Kluwer
Webb WR, Stern EJ, Kanth N et al (1993) Dynamic pulmonary CT findings in normal adult men. Radiology 186:117–124
Stern EJ, Webb WR (1994) Dynamic quantitative computed tomography: a predictor of pulmonary function in obstructive lung diseases. Invest Radiol 29:564–569
Lohrmann C, Uhl M, Kotter E, Burger D et al (2005) Pulmonary manifestations of Wegener granulomatosis: CT findings in 57 patients and review of the litterature. Eur J Radiol 53: 471–477
Langford AC (2005) Update on Wegener’s granulomatosis. Cleveland Clin J Med 72: 689–697
Zycinska K, Wardyn KA, Zycinski Z, Zielonka TM (2008) Association between clinical activity and highresolution tomography findings in pulmonary Wegener’s granulomatosis. J Physiol Pharmacol 59:833–838
Gurney WJ, Winer-Muram TH, Stern JE et al (2006) Diagnostic Imaging — Chest, Amirsys Inc
Lee SK, Kim ST, Fujimoto K et al (2003) Thoracic manifestation of Wegener’s granulomatosis: CT findings in 30 patients. Eur Radiol 13:43–51
Travis WD, Hoffman GS, Leavitt RY et al (1991) Surgical pathology of the lung in Wegener’s granulomatosis. Review of 87 open lung biopsies from 67 patients. Am J Surg Pathol 15:315–333
Polychronopoulos VS, Prakash UB, Goblin JM et al (2007) Airway involvement in Wegener’s granulomatosis. Rheum Dis Clin North Am 33:755–775
Frazier AA, Rosado-de-Christenson LM, Galvin RJ, Fleming VM (1998) Pulmonary angiitis and granulomatosis: radiologic-pathologic correlation. Radiographics 18:687–710
Maskell GF, Lockwood CM, Flower CDR (1993) Computed tomography of the lung in Wegener’s granulomatosis. Clin Radiol 48:377–380
Papiris SA, Manoussakis MN, Drosos AA et al (1992) Imaging of thoracic Wegener’s granulomatosis: the computed tomographic appearance. Am J Med 93:529–536
Weir IH, Muller NL, Chiles C et al (1992) Wegener’s granulomatosis: findings from computed tomography of the chest in 10 patients. J Can Assoc Radiol 43:31–34
Foo SS, Weisbrod GL, Herman SJ, Chamberlain DW (1990) Wegener’s granulomatosis presenting on CT with atypical bronchovasocentric distribution. J Comput Assist Tomogr 14:1004–1006
Stern EJ, Frank MS (1994) Small airway disease of the lungs: findings at expiratory CT. AJR 163:37–41
Hansell MD, Bankier AA, MacMahon H (2008) Fleischner Society: Glossary of terms for thoracic imaging. Radiology 246:697–722
Aquino SL, Webb WR, Golden J (1994) Bronchiolitis obliterans associated with rheumatoid arthritis: findings on HRCT and dynamic expiratory CT. J Comput Assist Tomogr 18:555–558
Arakawa H, Webb WR (1998) Air trapping on expiratory high-resolution CT scans in the absence of inspiratory scan abnormalities: correlation with pulmonary function tests and differential diagnosis. AJR 170:1349–1353
Author information
Authors and Affiliations
Corresponding authors
Rights and permissions
About this article
Cite this article
Magkanas, E., Detorakis, E., Nikolakopoulos, I. et al. Air trapping in Wegener’s granulomatosis: an additional finding on expiratory chest HRCT. Radiol med 116, 858–867 (2011). https://doi.org/10.1007/s11547-011-0675-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11547-011-0675-8