Inferior accessory fissure of the lung
Citation, DOI, disclosures and article data
Citation:
Knipe H, Hacking C, Chieng R, et al. Inferior accessory fissure of the lung. Reference article, Radiopaedia.org (Accessed on 13 Mar 2025) https://doi.org/10.53347/rID-22331
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rID:
22331
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Disclosures:
At the time the article was created Henry Knipe had no recorded disclosures.
View Henry Knipe's current disclosures
Last revised:
Disclosures:
At the time the article was last revised Craig Hacking had the following disclosures:
- Philips Australia, Paid speaker at Philips Spectral CT events (ongoing)
These were assessed during peer review and were determined to not be relevant to the changes that were made.
View Craig Hacking's current disclosures
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Synonyms:
- Inferior accessory fissure
- Twining's line (lung)
- Twining's lines (lung)
The inferior accessory fissure of the lung, also known as Twining's line, divides the medial basal bronchopulmonary segment from the rest of the lower lobe 4.
On this page:
Epidemiology
This accessory fissure is present in around 12% of people when examined with CT 3and is visible on 8% of PA chest x-rays 4. It is approximately five times more common on the right than the left.
Radiographic features
It is commonly incomplete and may only extend for 0.5-2 cm 1,3.
History and etymology
The line on CXR was described by British radiologist Edward Wing Twining (1887-1939) who also described Twining's line of the posterior cranial fossa 5.
References
- 1. 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
- 2. Misra RR, Uthappa MC, Power N et-al. Radiology Picture Tests for the FRCR. Greenwich Medical Media. ISBN:1841100390. Read it at Google Books - Find it at Amazon
- 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
- 5. Isherwood I. Edward Wing Twining, 1887-1939. (1995) AJNR. American journal of neuroradiology. 16 (10): 2077-80. Pubmed
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