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Anomalous inferior vena cava with azygos continuation in a Japanese man

Yoshiyuki Tohno1, Setsuko Tohno, Shin-Ichi Kosugi

  • 1Department of Anatomy, Nara Medical University School of Medicine, Kashihara, Nara, Japan. ytohno@naramed-u.ac.jp

Anatomical Science International
|March 21, 2007
PubMed

Insights

A rare anatomical variation, anomalous inferior vena cava with azygos continuation, was identified in a cadaver. This finding details the unusual joining of left and right inferior vena cavae and their continuation via the azygos vein.

Area of Science:

  • Anatomy
  • Medical Education
  • Vascular Anatomy

Background:

  • Anatomical variations of the inferior vena cava (IVC) are uncommon but clinically significant.
  • Understanding these variations is crucial for accurate interpretation of medical imaging and surgical planning.
  • Dissections provide valuable opportunities for medical students to encounter and learn about such anomalies.

Observation:

  • A unique case of anomalous inferior vena cava with azygos continuation was discovered during a routine dissection.
  • The anomaly involved the presence of both left and right inferior vena cavae, which merged at the L1 vertebral level.
  • The confluence continued as the azygos vein, which then drained into the superior vena cava at the T5 vertebral level.

Findings:

  • The identified anomaly represents a rare congenital variation in the development of the venous system.
  • Detailed anatomical description of the anomalous IVC and its continuation via the azygos vein was documented.
  • The heart's structure was noted to be normal, ruling out associated cardiac malformations in this specific case.

Implications:

  • This case highlights the importance of recognizing rare vascular anomalies in anatomical studies.
  • Awareness of such variations can prevent misdiagnosis in clinical settings, particularly in radiology and cardiothoracic surgery.
  • Such findings contribute to the existing knowledge base of human anatomical diversity and its clinical relevance.

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