[Thin-section computed tomography of the normal minor fissure]

Area of Science:

• Thoracic anatomy
• Radiology
• Pulmonary imaging

Background:

• The minor fissure, a key anatomical landmark in the right lung, plays a role in disease localization.
• Understanding its detailed anatomy and variations is crucial for accurate radiological interpretation.

Purpose of the Study:

• To characterize the anatomical details and variations of the minor fissure using thin-section computed tomography (CT).
• To assess the completeness and positional variations of the minor fissure.
• To evaluate the relationship between the minor fissure and adjacent structures, particularly the anterior vein of the anterior segment of the right upper lobe (V3b).

Main Methods:

• Thin-section computed tomography (CT) scans (2 mm thickness, 3 mm interval) were analyzed in 50 patients.
• The completeness, highest and lowest portions, and relationships of the minor fissure were assessed.
• Three-dimensional (3D) reconstruction was utilized to enhance anatomical understanding.

Main Results:

• The minor fissure was visualized in all patients, with varying degrees of completeness observed in 41 patients (29% complete, 44% slightly incomplete, 17% half incomplete, 10% considerably incomplete).
• The highest portion of the minor fissure showed significant positional variability (hilar, dorsal, central locations being most common).
• The anterior vein of the anterior segment of the right upper lobe (V3b) contacted the minor fissure in 40% of patients, often correlating with medial incompleteness of the fissure.

Conclusions:

• The minor fissure exhibits considerable anatomical variation in completeness and position.
• Awareness of these variations, especially in relation to structures like V3b, is essential for accurate interpretation of thoracic imaging.
• Detailed anatomical knowledge of the minor fissure aids in the precise localization and assessment of pulmonary lesions.