Poland syndrome

Answer

Diagnosis: Poland syndrome

Differential diagnosis for unilateral hyperlucent hemithorax is long and includes:

1.        Chest wall abnormalities

·          congenital: Poland syndrome

·          postsurgical: mastectomy

2.        Pleural abnormalities (pneumothorax, contralateral pleural effusion)

3.        Lung abnormalities

·          congenital: congenital lobar overinflation/emphysema

·          postsurgical: pneumonectomy, unilateral lung transplant

·          large airway related:

ü   external bronchial compression (hilar mass, cardiomegaly)

ü   endobronchial obstruction with air trapping (foreign body, lesion, mucous plug)

·          small airway related:

ü   obliterative bronchiolitis

ü   Swyer-James syndrome

·          parenchymal: asymmetric emphysema, unilateral bullae

4.        Vascular causes (asymmetric perfusion)

·          congenital: pulmonary artery hypoplasia/ absence or pulmonary artery stenosis

·          postsurgical: shunts (e.g. Blalock-Taussig)

pulmonary embolism (Westermark sign)

 

DISCUSSION

Poland syndrome is a rare congenital disorder characterized by unilateral absence of the pectoralis muscles. This spectrum of abnormalities includes aplasia or hypoplasia of pectoralis major (most common), pectoralis minor, rarely additional muscles (serratus, latissimus dorsi and external oblique), ipsilateral ribs, most commonly 2nd to 5th, ipsilateral breast or nipple, deficiency/absence of subcutaneous fat and axillary hair. It can be associated with ipsilateral upper limb abnormalities, namely short arm/forearm, small hand and brachysyndactyly, and simian crease. In this case, as seen on CT, the pectoralis major and minor were absent and the right nipple was atrophic.

It is thought to result from an isolated vascular insult in early gestation, however a rare familiar form has been also described. It may coexist with other congenital abnormalities (e.g. Mobius syndrome).

It is a benign condition, usually with mild functional disability, and often require no treatment, sometimes cosmetic surgery can be performed (breast implants).

Selected Readings:

1. Jeung MY, Gangi A, Gasser B et al. Imaging of chest wall disorders. Radiographics. 19 (3): 617-37.

2. Fokin A, Robiscek F. Poland’s syndrome revisited.  The Annals of Thoracic Surgery, 74 (6): 2218 – 2225

3. Morani AC, Ramani NS. Poland syndrome. Pediatric Radiology (2010) 40:S1, 51-51

4. Iyer RS, Parisi MT. Multimodality imaging of Poland syndrome with dextrocardia and limb anomalies. Clin Nucl Med 2012;37:815-6.  

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