Unilateral absence of pulmonary artery: a radiographically occult cause of life-threatening hemoptysis

Unilateral absence or agenesis of pulmonary artery (UAPA) is a rare congenital abnormality with an estimated prevelance of 1 in 2,00,000 adults. The entity occurs commonly in association with other congenital heart diseases like septal defects or patent ductus arteriosus. The condition usually runs a benign clinical course with patients usually presenting clinically in adulthood with history of recurrent respiratory tract infections. Two such patients presented with recurrent respiratory tract infections, breathlessness and hemoptysis. The chest radiograph of first patient was reported as normal in the referring hospital, while that of second patient showed volume loss in left lung. CT Pulmonary Angiography (CTPA) was then performed which demonstrated the absence of right and left pulmonary arteries respectively in the first and second patients. Pulmonary artery branches were reformed distally by multiple collaterals arising from systemic arteries. The entire spectrum, including embryology, imaging features and management of UAPA are discussed. UAPA remains a potential cause for life-threatening hemoptysis, due to extensive collateralization associated with the condition. It is important for radiologists to be aware of this uncommon entity in order to suspect it on a routine chest radiograph, diagnose it and map associated collaterals on CTPA and also embolize the bleeding collaterals.

Isolated sternal hypoplasia: a rare cause of kyphoscoliosis

In most cases, kyphoscoliosis is idiopathic. However, this is a diagnosis of exclusion and can be made only if no cause can be identified. Kyphoscoliosis can occur due to various causes. Isolated sternal anomalies may also cause kyphoscoliosis secondary to the bony deformity though this has not previously been reported in literature. We have reported a case of kyphoscoliosis secondary to isolated sternal hypoplasia with complete absence of bony and cartilaginous elements of the body and xiphoid process of the sternum without any associated deformities of mediastinal structures, lung parenchyma or soft tissues in a young male patient. Careful evaluation of patients with kyphoscoliosis can ensure timely diagnosis of unusual and potentially treatable causes for the same such as sternal anomalies. Addition of lateral chest radiographs to the imaging protocol for evaluation of kyphoscoliosis can play a major role in timely diagnosis of such cases.