Sol Azygos Lobu? Aberran Bir Ven Tarafından Sol Üst Lobun Medialde Tuzaklanması

Yıl 2025, Cilt: 6 Sayı: 2, 48 - 54, 07.09.2025

Şeref Barbaros Arık

Öz

Giriş: Azygos sistemin anatomik varyasyonları nadirdir ancak özellikle görüntülemede patolojik bulgularla karıştırıldığında önemlidir. Bu varyasyonlar arasında, sol azygos lobu ve ona eşlik eden venöz anomali oldukça nadir olup genellikle fark edilmez. Bu vaka temelli radyolojik analiz aracılığıyla, sol azygos lobu ve ona eşlik eden venin anatomik, embriyolojik ve klinik önemini tanımlamak amaçlanmıştır.

Olgu: Bu tanımlayıcı çalışma, nadir görülen bir sol azygos lob konfigürasyonu oluşturan aberan sol superior posterior interkostal ven tarafından sol üst lobun mediyal tuzağa düşmesini gösteren bir vakayı sunmaktadır. Vasküler ve parankimal anatomiyi görüntülemek için çok dedektörlü bilgisayarlı tomografi ve multiplanar rekonstrüksiyonlar kullanılmıştır. Radyolojik ve anatomik literatür temelinde embriyolojik ilişkiler ve olası klinik sonuçlar da gözden geçirilmiştir.

Bulgular: Görüntüleme, aort kavsi ile akciğer tepesi arasında seyreden dilate bir ven tarafından mediyal olarak yer değiştirmiş sol üst lob ile birlikte bir sol azygos lob varyantını ortaya koymuştur. Bu ven, bronkovasküler ayrım olmaksızın yalancı bir fissür oluşturan sol superior posterior interkostal ven olarak tanımlanmıştır. Bu varyasyon, akciğer grafisinde yumuşak doku kitlesi olarak taklit edilmiş, kesitsel bilgisayarlı tomografi ile açıklığa kavuşturulmuştur. Bu anomalinin tanınması gereksiz tanısal girişimlerin önüne geçmiştir.

Sonuç: Sol azygos lobu ve ona eşlik eden ven gibi nadir venöz anomalilerin farkında olmak, radyologlar için yanlış tanıların önlenmesi açısından çok önemlidir. BT görüntüleme, bu tür varyasyonların güvenilir şekilde tanımlanmasını sağlar ve torasik venöz anatomiyi anlamayı geliştirerek cerrahi ve girişimsel planlamaya katkıda bulunur.

Anahtar Kelimeler

Azygos lob , Sol superior interkostal ven , Anatomik varyasyon , Torasik BT , Venöz anomali , Embriyoloji

Left Azygos Lobe? Medial Entrapment of the Left Upper Lobe by an Aberrant Vein

Öz

Introduction: Although anatomical variations of the azygos system are uncommon, they hold clinical significance, particularly when misinterpreted as pathological findings on imaging. Among these variations, the presence of a left azygos lobe and its associated venous anomaly are especially rare and often under-recognized.This study aims to raise awareness of the left azygos lobe and its associated vein as an uncommon venous variation, and to highlight its anatomical, embryological, and clinical relevance through radiological illustrations and literature review.

Case: This descriptive study presents cases illustrating medial entrapment of the left upper lobe by an aberrant left superior posterior intercostal vein, forming a rare left azygos lobe configuration. Multidetector computedtomography with multiplanar reconstructions was used to visualize vascular and parenchymal anatomy. Embryological correlations and potential clinical implications were also examined through a review of relevant radiological and anatomical literature.

Results: Imagings revealed left azygos lobe variant with a medially displaced left upper lobe, entrapped by a dilated vein coursing between the aortic arch and the lung apex. The vein was identified as left superior posterior intercostal vein, forming a pseudo-fissure without bronchovascular separation. This variation mimicked a soft tissue mass on chest radiography and was clarified by cross-sectional computed tomography. Recognition of this anomaly prevented unnecessary diagnostic procedures.

Conclusion: The awareness of rare venous anomalies, such as the left azygos lobe and its associated vein, is essential for radiologists to avoid misdiagnosis. Computed tomography imaging offers reliable identification of such variations and enhances understanding of thoracic venous anatomy, aiding in surgical and interventional planning. Improved awareness of these variations can prevent misdiagnosis and guide future prevalence-based studies.

Anahtar Kelimeler

Azygos lobe; Left superior intercostal vein; Anatomical variation; Thoracic CT; Venous anomaly; Embryology

Kaynakça

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