Scintigraphy, angiography and computed tomography in unilateral hyperlucent lung due to obliterative bronchiolitis

Comparison of ventilation-perfusion scintigraphy with MR angiography in patients with Swyer-James syndrome

PURPOSE

The aim of this study was to establish the value of magnetic resonance angiography (MRA) in diagnosing) Swyer-James syndrome (SJS) and to compare MRA and ventilation-perfusion (V/Q) scan results in patients with established SJS.

METHODS

The V/Q scans and the MRA findings of 22 lungs of 11 patients with SJS (6 males, 5 females; age range: 17-69 years, mean: 38.4 years) were retrospectively studied. The perfusion scan was performed after the injection of Tc macroaggregated albumin. After 2 days, the ventilation scan was performed by using Tc diethylene triamine penta-acetic acid aerosol. The MRA was performed with a 1.5 T magnetic resonance unit. We compared the MRA and V/Q scan findings of the lungs of the patients.

RESULTS

The V/Q scans showed the characteristic pattern of a matched V/Q defect on the affected lungs. The MRA displayed a smaller pulmonary artery and markedly poor peripheral vasculature on the affected side in all patients. The MRA had a sensitivity of 84.6%, a specificity of 100% for the detection SJS. Interobserver variability was minimum as indicated by a weighted kappa statistic of 0.818.

CONCLUSION

This study indicates that the MRA is a fast, accurate, without radiation, and noninvasive technique for supporting the diagnosis of SJS. But, V/Q scans showed additional segmental perfusion/ventilation abnormalities on contralateral lung to reveal the segmental involvement of SJS. As a result, the MRA has no more any extra advantages for patient management.

Utility of ventilation and perfusion scan in the diagnosis of young military recruits with an incidental finding of hyperlucent lung

Swyer-James-MacLeod syndrome (SJMS) is considered to be a relatively uncommon disease presenting with unilateral hyperlucent lung due to hypoplasia of a pulmonary artery and bronchiectasis of the affected lung. In this report, we describe the ventilation-perfusion (V/Q) scan findings of nine male recruits (aged 20-29 years, mean 24.4+/-2.96 years) with SJMS in whom the diagnosis was first established in adulthood. V/Q scan findings of all patients were compared with those on planar radiographs, pulmonary function studies, high resolution computed tomography (HRCT) and digital subtraction angiography (DSA). The ventilation (133Xe) and perfusion (99Tcm-macro-aggregated albumin) scans showed the characteristic pattern of a matched V/Q defect and marked air trapping on the washout phase on 133Xe scintigraphy. HRCT displayed hypodense lung with integrity of main airways, and markedly diminished vasculature on the affected side in all patients. A smaller pulmonary artery on the affected side with poor peripheral vasculature was observed with DSA in all patients. All patients had features of obstructive airway disease in varying degrees on pulmonary function studies. In contrast to other imaging methods, bronchiectasis as an etiological factor was displayed on HRCT. Some pulmonary areas, which were normal on HRCT and planar radiographs, showed air trapping on V/Q scan. Although a V/Q scan was more helpful in determining the extent of the disease and correlates well with conventional imaging methods, HRCT was the most valuable imaging method for the evaluation of aetiology in unilateral hyperlucent lung.

Swyer-James syndrome documented by spiral CT angiography and high resolution inspiratory and expiratory CT: an accurate single modality exploration

Spiral CT angiography was performed in a patient suspected of having pulmonary embolism. The right pulmonary system was normal. The left arterial system was small but patent. The left upper lobe was small and hyperlucent. The left lower lobe was collapsed and contained bronchiectasis. The bronchi were patent. High resolution CT in inspiration and expiration confirmed air trapping in the left upper lobe. A diagnosis of Swyer-James syndrome of the left upper lobe was made.