Left horizontal fissure
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At the time the article was created Eric F Greif had no recorded disclosures.
View Eric F Greif's current disclosuresAt the time the article was last revised Raymond Chieng had no financial relationships to ineligible companies to disclose.
View Raymond Chieng's current disclosures- Left minor fissure
- Left minor accessory lung fissure
The left horizontal (or minor) fissure is an accessory fissure found in 1.6-8% of individuals 1,3,4.
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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 2.
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 2. It tends to be dome-shaped on at least one projection.The fissure infrequently has a horizontal course 1.
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
References
- 1. Austin JH. The left minor fissure. Radiology. 1986;161 (2): 433-6. Pubmed citation
- 2. Godwin JD, Tarver RD. Accessory fissures of the lung. AJR Am J Roentgenol. 1985;144 (1): 39-47. doi:10.2214/ajr.144.1.39 - Pubmed citation
- 3. Yildiz A, Gölpinar F, Calikoğlu M, Duce MN, Ozer C, Apaydin FD. HRCT evaluation of the accessory fissures of the lung. European journal of radiology. 49 (3): 245-9. doi:10.1016/S0720-048X(03)00137-2 - Pubmed
- 4. Stephanie Ryan, Michelle McNicholas, Stephen J. Eustace. Anatomy for Diagnostic Imaging. (2011) Page 126. ISBN: 9780702029714 - Google Books
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