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 uncomm on 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 re cruits (aged 20-29 years, mean 24.4+/-2.96 years) with SJMS in whom the dia gnosis was first established in adulthood. V/Q scan findings of all patient s were compared with those on planar radiographs, pulmonary function studie s, high resolution computed tomography (HRCT) and digital subtraction angio graphy (DSA). The ventilation (Xe-133) and perfusion (Tc-99(m)-macro-aggreg ated albumin) scans showed the characteristic pattern of a matched V/Q defe ct and marked air trapping on the washout phase on Xe-133 scintigraphy. HRC T displayed hypodense lung with integrity of main airways, and markedly dim inished vasculature on the affected side in all patients. A smaller pulmona ry artery on the affected side with poor peripheral vasculature was observe d with DSA in all patients. All patients had features of obstructive airway disease in varying degrees on pulmonary function studies. Ln contrast to o ther imaging methods, bronchiectasis as an etiological factor was displayed on HRCT. Some pulmonary areas, which were normal on HRCT and planar radiog raphs, showed air trapping on V/Q scan. Although a V/Q scan was more helpfu l in determining the extent of the disease and correlates well with convent ional imaging methods, HRCT was the most valuable imaging method for the ev aluation of aetiology in unilateral hyperlucent lung. ((C) 2001 Lippincott Williams & Wilkins).