left horizontal fissure

Akzessorischer
Lappenspalt links, "Mittellappen links". Der horizontale Lappenspalt reicht nicht wie rechts an den diagonalen Lappenspalt heran.
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Left
horizontal fissure • Accessory left horizontal fissure with lingular pneumonia - Ganzer Fall bei Radiopaedia
Dixon A, Accessory left horizontal fissure with lingular pneumonia. Case study, Radiopaedia.org (Accessed on 17 May 2023) https://doi.org/10.53347/rID-53763 • CC by-nc-sa 3.0 (modified)
Radiopaedia • CC-by-nc-sa 3.0 • de

The left horizontal (or minor) fissure is an accessory fissure found in around 8% of individuals examined with CT . In a prospective study of 2,000 consecutive normal chest X-rays (AP and lateral), a definite left horizontal fissure was identified in 1.6% of the subjects .

Gross anatomy

The left horizontal fissure separates the lingula from the rest of the left upper lobe (anterior-apicoposterior segments). The segmental anatomy of the left lung is preserved, despite the accessory fissure, with the lingula retaining its superior and inferior segments rather than assuming the lateral and medial arrangement of the right middle lobe segments .

Radiographic features

Plain radiograph

On frontal radiographs, the fissure resembles the right horizontal fissure, except that it may be higher (more common) or lower. The fissure usually slopes caudally from its medial to its lateral margin . It tends to be dome-shaped on at least one projection.The fissure infrequently has a horizontal course .

Like the right horizontal fissure, it can become conspicuous on plain film by air space opacification on either side or pleural effusion involving it.

Differential diagnosis

Consider:

  • pleural-parenchymal scarring
Siehe auch:
und weiter:
Assoziationen und Differentialdiagnosen zu horizontaler Lappenspalt links:
akzessorische
Lungenlappen
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Mittellappen
 
Wikipedia • CC BY-SA 4.0