A 52-year-old man undergoes CT chest for staging of lung cancer. The radiologist notes a tumor in the right upper lobe. Regarding the bronchopulmonary segments of the right upper lobe, all of the following are correct EXCEPT:

Explanation

## Bronchopulmonary Segments of the Right Upper Lobe ### Anatomy of Right Upper Lobe Segments **Key Point:** The right upper lobe is divided into **three bronchopulmonary segments**: 1. **Apical segment** — most superior 2. **Posterior segment** — posteriorly located 3. **Anterior segment** — anteriorly located ### Correct Statements **High-Yield:** The apical segment is supplied by the most superior segmental bronchus (the apical segmental bronchus arises first from the right upper lobe bronchus). **Key Point:** The posterior segment lies posteriorly and has its own distinct segmental bronchus, artery, and vein — it is a completely independent functional unit. **Key Point:** Each bronchopulmonary segment is a functionally independent unit with its own segmental bronchus, segmental artery, and segmental vein. This anatomical independence is crucial for surgical resection. ### The Incorrect Statement **High-Yield:** The **anterior segment is NOT the largest** of the three right upper lobe segments. The **apical segment** is the largest, followed by the posterior segment, with the anterior segment being the smallest. This is a commonly tested distinction in NEET PG. ### Mnemonic for Right Upper Lobe Segments **Mnemonic:** **"APA"** (Apical, Posterior, Anterior) — arranged from superior to inferior and posterior to anterior. The **Apical** segment is the **largest**. ### Clinical Pearl **Clinical Pearl:** Understanding segment size is clinically important for tumor staging and surgical planning. A tumor in the apical segment of the right upper lobe has different implications for resection margin and lymph node involvement than one in the smaller anterior segment. ### Comparison Table: Right Lung Segments | Lobe | Segments | Number | Largest Segment | | --- | --- | --- | --- | | Right Upper | Apical, Posterior, Anterior | 3 | Apical | | Right Middle | Lateral, Medial | 2 | Lateral | | Right Lower | Superior, Medial basal, Anterior basal, Lateral basal, Posterior basal | 5 | Superior | | Left Upper | Apical-posterior, Anterior, Superior lingula, Inferior lingula | 4 | Apical-posterior | | Left Lower | Superior, Anteromedial basal, Lateral basal, Posterior basal | 4 | Superior |