CTICasesHypoplastic Right Lung with Persistent Left SVC, Tracheal Bronchus, and Absent Right Fissures
Imaging findings
CT demonstrates rightward mediastinal shift from a hypoplastic right lung with absent or poorly formed pulmonary fissures on the right. A tracheal bronchus arises from the right aspect of the trachea. The right bronchial tree has an anomalous branching pattern with a small right upper lobe and unusual basal segmentation, suggestive of left lung isomerism. A persistent left superior vena cava is identified draining into a dilated coronary sinus, without a bridging brachiocephalic vein. Bilateral hyparterial bronchi are identified, further supporting left lung isomerism. Abdominal imaging shows a single spleen without asplenia findings.
Key takeaways
Left lung isomerism (polysplenia syndrome) can present with bilateral hyparterial bronchi, left-sided bilateral anatomy, persistent left SVC draining into a dilated coronary sinus without right atrial connection, and associated lung hypoplasia with anomalous airway branching. When a tracheal bronchus and hypoplastic lung are seen together, the combination with bilateral hyparterial bronchi and a persistent left SVC should suggest left isomerism rather than isolated scimitar syndrome (which would require anomalous pulmonary venous drainage to the systemic veins). Careful assessment of bronchial morphology on sagittal reformats is the key to recognizing bilateral hyparterial versus one hyparterial and one hyparterial configuration.
AI-assisted summary — may contain errors. Verify against the source video. Learn more
More from this webinar
- NUT Carcinoma (Midline NUT Carcinoma)Neoplastic
- Bronchial Artery Origin Mimicking Aortic Intimal InjuryArtifact
- Bilateral Foramen of Morgagni HerniasCongenital
- Right Atrial Myxoma with OssificationNeoplastic
- Congenital Bronchial AtresiaCongenital
- Loeys-Dietz Syndrome with Pectus CarinatumCongenital
- Mycobacterium Avium Complex (MAC) Infection Misidentified as SilicosisInfection
- Hypersensitivity Pneumonitis Progressing to FibrosisILD
See all cases from September 21, 2017 →
Related Congenital cases
- Large Right Upper Lobe Pulmonary Vein with Mass Effect on Bronchus Intermedius
- Dual Left Anterior Descending Artery (Dual LAD) Coronary Variant
- Pulmonary Artery Sling Incidentally Discovered on Lung Cancer Screening CT
- Congenital Systemic-to-Pulmonary Artery Fistula — Internal Mammary Artery to Left PA
- Complex Pleuropulmonary Lymphatic-Venous Malformation
- Right Aortic Arch with Mirror-Image Branching and Right Ligamentum Arteriosum