Original articleAn Anatomical Study of the Inferior Oblique Muscle: The Embalmed Cadaver vs the Fresh Cadaver
Section snippets
Methods
Thirty-one cadavers were obtained with permission from the Anatomy and Cell Biology Department at Hanyang University. The age at the time of death was 63 ± 16 years (mean ± standard deviation). All cadavers were registered with Hanyang University, and appropriate consents and approvals were obtained prior to use.
This study involved 40 intact orbits of 20 embalmed adult cadavers, and 22 orbits of 11 fresh cadavers (with no formaldehyde preservative used) that had not previously been thawed. The
Inferior Oblique Muscle Anatomic Variables in Embalmed and Fresh Cadavers
The distances from the apex of the lacrimal fossa and from the inferior orbital rim to the origin of the IO were 17.48 ± 1.92 mm and 1.08 ± 0.82 mm, respectively. The width of the origin was 2.72 ± 0.78 mm, and the angle between the IO and the inferior orbital rim was 28.87 ± 10.51 degrees (Figure 1). The width of the muscle belly was 7.08 ± 1.14 mm, and the neurovascular bundle entered the IO at 17.15 ± 2.99 mm from the insertion. The width of the IO insertion was 9.27 ± 1.35 mm. The distances
Discussion
The anatomic studies of Fink1 on the oblique muscles have been followed by many studies on IO anatomy, especially regarding the insertional patterns, for which a wide range of incidence rates of multiple insertions and bellies has been reported (2% to 91.7%).2, 3, 4, 5, 6, 7, 8, 9 In our study, divided bellies of IOs were found in 27.4% of the total cadaveric orbits examined.
There are several possible reasons for the diverse results from the previous studies. First, the preservation status of
Sun Young Shin, MD, received her MD from Hanyang University Medical School, Seoul, Republic of Korea in 1997, where she also completed her residency in the Department of Ophthalmology with subsequent sub-speciality training on the pediatric ophthalmology and strabismus. Dr Shin is a former Assistant Professor at the Department of Ophthalmology, College of Medicine, Hanyang University from 2005 to 2007. She is currently an Assistant Professor at the Department of Ophthalmology and Visual Science
References (9)
Bifid insertion of the inferior oblique muscle
Am J Ophthalmol
(1982)- et al.
Inferior oblique muscle recession
Am J Ophthalmol
(1978) - et al.
Anatomic variations of the inferior oblique muscle: a potential cause of failed inferior oblique weakening surgery
Am J Ophthalmol
(1999) - et al.
The double-bellied inferior oblique muscle: clinical correlates
J AAPOS
(2001)
Cited by (13)
Hyperselective neurectomy in the treatment of elbow and wrist spasticity: an anatomical study and incision design
2024, British Journal of NeurosurgeryHandbook of Muscle Variations and Anomalies in Humans: A Compendium for Medical Education, Physicians, Surgeons, Anthropologists, Anatomists, and Biologists
2022, Handbook of Muscle Variations and Anomalies in Humans: A Compendium for Medical Education, Physicians, Surgeons, Anthropologists, Anatomists, and BiologistsThe oblique extraocular muscles in cetaceans: Overall architecture and accessory insertions
2021, Journal of AnatomyOptical coherence tomography of the orbit through a staphyloma: A view of tenon's capsule, orbital fat, and inferior oblique muscle
2021, Journal of Pediatric Ophthalmology and StrabismusIntramuscular Nerve Distribution of the Inferior Oblique Muscle
2020, Current Eye ResearchDetailed anatomy of the trochlear nerve in the superior oblique muscle
2019, Graefe's Archive for Clinical and Experimental Ophthalmology
Sun Young Shin, MD, received her MD from Hanyang University Medical School, Seoul, Republic of Korea in 1997, where she also completed her residency in the Department of Ophthalmology with subsequent sub-speciality training on the pediatric ophthalmology and strabismus. Dr Shin is a former Assistant Professor at the Department of Ophthalmology, College of Medicine, Hanyang University from 2005 to 2007. She is currently an Assistant Professor at the Department of Ophthalmology and Visual Science at The Catholic University of Korea, Seoul, Korea.