Horizontal fissure
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View Jeremy Jones's current disclosuresAt the time the article was last revised Ciléin Kearns had no financial relationships to ineligible companies to disclose.
View Ciléin Kearns's current disclosures- minor fissure
- transverse fissure
The horizontal fissure, also called the minor fissure or transverse fissure, is a unilateral structure in the right lung that separates the right middle lobe from the right upper lobe.
On this page:
Gross anatomy
The horizontal fissure arises from the right oblique fissure and follows the 4th intercostal space from the sternum until it meets the oblique fissure as it crosses the right 5th rib 1.
Variant anatomy
The horizontal fissure is highly variable and can be incomplete or absent in some patients. According to different postmortem dissection studies, the prevalence of incomplete horizontal fissures can vary between 8-35% and may be absent in 3-50% of right lungs 2-4.
A minority of individuals have a horizontal fissure in the left lung, independent of the right horizontal fissure.
Radiographic features
The horizontal fissure can be visualized on both conventional radiography and computed tomography (CT) scans.
Plain radiograph
It is seen in ~65% (range 5-80%) of normal frontal chest radiographs as a thin line running horizontally from the edge of right lung towards the right hilum, at approximately the level of the anterior 4th rib 5.
References
- 1. Gray's Anatomy for Students: With STUDENT CONSULT Online Access, 3e. Churchill Livingstone. ISBN:0702051314. Read it at Google Books - Find it at Amazon
- 2. Nene, Ajay Ratnakarrao, Krishna Swami Gajendra, and M. V. Sarma. "Lung lobes and fissures: a morphological study." Anatomy 5 (2011): 30-38.
- 3. George BM, Nayak SB, Marpalli S. Morphological variations of the lungs: a study conducted on Indian cadavers. Anat Cell Biol. 2014;47 (4): 253-8. doi:10.5115/acb.2014.47.4.253 - Free text at pubmed - Pubmed citation
- 4. Meenakshi S, Manjunath KY, Balasubramanyam V. Morphological variations of the lung fissures and lobes. Indian J Chest Dis Allied Sci. 2005;46 (3): 179-82. Pubmed citation
- 5. Webb WR, Higgins CB. Thoracic Imaging. Lippincott Williams & Wilkins. (2010) ISBN:1605479764. Read it at Google Books - Find it at Amazon
- 6. Kc S, Shrestha P, Shah A, Jha A. Variations in Human Pulmonary Fissures and Lobes: A Study Conducted in Nepalese Cadavers. Anat Cell Biol. 2018;51(2):85-92. doi:10.5115/acb.2018.51.2.85 - Pubmed
Incoming Links
- Pleura
- Right upper lobe anterior segment
- Right lower lobe collapse
- Lung fissures
- Right middle lobe collapse
- Right upper lobe consolidation
- Right lung
- Right upper lobe collapse
- Right upper lobe posterior segment
- Lung
- Pneumonia (summary)
- Chest radiograph assessment using ABCDEFGHI
- Right middle lobe
- Vertical fissure line in the lung
- Right middle lobe consolidation
- Right upper lobe
- Left horizontal fissure
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