Abstract
The terms abusive head injury and shaken baby syndrome are used to describe a unique pattern of nonaccidental traumatic injuries occurring in children that many clinicians and researchers have good reason to believe is caused by violent shaking. Typical injuries include severe brain injury, with intracranial and retinal hemorrhages, but the pathogenesis of injuries is poorly understood. A major paradox in head trauma in infants is that the injuries induced by a shaking event are much more severe than those caused by even very violent single-impact head trauma, despite the relatively low accelerations in shaking.
We have developed a finite element computer model of the eye, orbit, and orbital bone and used it to simulate the effects of single-impact and oscillatory motion inputs. The model was informed by data from semiquantitative in vitro anatomical traction experiments on in situ rabbit eyes. The new results reported here strongly suggest that suction between the eye and its surrounding fat dominates the dynamical stability of the system composed of the eye, its socket, and the components and material supporting the eye. Computer simulations incorporating this functional anatomical relationship show that deceleration of the head generates pressure gradients inside and outside the eye; these could cause damaging shear stresses in structures such as the retina and blood vessels. Simulations also show that oscillating the bone of the orbit causes the eye to move anteriorly and posteriorly with an increasing amplitude, building up the stresses within the eye over time. This is the first time that any biomechanical mechanism has been identified that might explain the disproportionally severe injuries caused by an oscillatory mechanism such as violent shaking of an abused infant. However, further study is required and this conclusion is therefore preliminary and provisional.
Similar content being viewed by others
References
Jayawant S, Rawlinson A, Gibbon F, et al. Subdural hemorrhages in infants: population based study. BMJ 1998;317:1558–1561.
Levin AV. Retinal hemorrhages and child abuse, in Recent Advances in Pediatrics. (David TJ, ed.), Churchill Livingstone, Edinburgh. 2000; pp. 151–219.
The Ophthalmology Child Abuse Working Party. Child abuse and the eye. Eye 1999;13:3–10.
Adams G, Ainsworth J, Butler L, et al. Update from the Ophthalmology Child Abuse Working Party Royal College Ophthalmologists. Eye 2004;18:795–798.
Green MA, Lieberman G, Milroy CM, Parsons MA. Ocular and cerebral trauma in non-accidental injury in infancy: underlying mechanisms and implications for pediatric practice. Br J Ophthalmol 1996;80:282–287.
Snodgrass GJ. The eye and the brain in non-accidental injury involving young children. Br J Ophthalmol 1996;80:275.
Wilkinson WS, Han DP, Rappley MD, Owings CL. Retinal hemorrhage predicts neurologic injury in the shaken baby syndrome. Arch Ophthalmol 1989;107:1472–1474.
Morad Y, Kim YM, Armstrong DC, Huyer D, Mian M, Levin AV. Correlation between retinal abnormalities and intracranial abnormalities in the shaken baby syndrome. Am J Ophthalmol 2002;134:354–359.
Lyle DJ, Stapp JP, Button RR. Ophthalmologic hydrostatic pressure syndrome. Am J Ophthalmol 1957;44:652–657.
David DB, Mears T, Quinlan MP. Ocular complications associated with bungee jumping. Br J Ophthalmol 1994;78:234–235.
Jain BK, Talbot EM. Bungee jumping and intraocular hemorrhage. Br J Ophthalmol 1994;78:236–237.
Chan J. Ophthalmic complications after bungee jumping. Br J Ophthalmol 1994;78:239.
Gilliland MG, Folberg, R. Shaken babies—some have no impact injuries. J Forensic Sci 1996;41:114–116.
Duhaime AC, Alario AJ, Lewander WJ, et al. Head injury in very young children: mechanisms, injury types, and ophthalmologic findings in 100 hospitalized patients younger than 2 years of age. Pediatrics 1992;90:179–185.
Pounder DJ. Shaken adult syndrome. Am J Forensic Med Pathol 1997;18:321–324.
Robinson DA. A quantitative analysis of extraocular muscle cooperation and squint. Invest Ophthalmol 1975;14:801–825.
Bron AJ, Tripathi RC, Tripathi BJ. The bony orbit and paranasal sinuses, in Wolff’s Anatomy of the Eye and the Orbit. Bron AJ, Tripathi RC, Tripathi BJ. 8th ed., Chapman & Hall Medical, London, 1997; pp. 1–29.
Power ED, Duma SM, Stitzel JD, et al. Computer modeling of airbag-induced ocular injury in pilots wearing night vision goggles. Aviat Space Environ Med 2002;73:1000–1006.
Bertocci GE, Pierce MC, Deemer E, Aguel F, Janosky JE, Vogeley E. Using test dummy experiments to investigate pediatric injury risk in simulated short-distance falls. Arch Pediatr Adolesc Med 2003;157:480–486.
Goldsmith W, Plunkett J. A biomechanical analysis of the causes of traumatic brain injury in infants and children. Am J Forensic Med Pathol 2004;25:89–100.
Welsh TJ, Gilman M. (1969), Voluntary propulsion of the eyes. Am J Ophthalmol 1969;67:583–585.
Duke-Elder S, Wybar K. The mechanics of the movement of the eyes. in System of Ophthalmology Vol VI Ocular Motility and Strabismus (Duke-Elder S. ed.), Henry Kimpton, London, 1973; pp. 136–144.
Patton N. Self-inflicted eye injuries: a review. Eye 2004;18:867–872.
Goldsmith W. Biomechanics of head injury. in Biomechanics:its foundations and objectives (Fung YC, Perrone N, and Anliker M, eds), Prentice-Hall, Hemel Hempstead, 1972; pp. 585–634.
Duhaime AC, Gennarelli TA, Thibault LE, Bruce DA, Margulies SS, and Wiser R. The shaken baby syndrome. A clinical, pathological, and biomechanical study. J Neurosurg 1987;66:409–415.
Cory CZ, Jones MD. Can shaking alone cause fatal brain injury? A biomechanical assessment of the Duhaime shaken baby syndrome model. Med Sci Law 2003;43:317–333.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Cirovic, S., Bhola, R.M., Hose, D.R. et al. Mechanistic hypothesis for eye injury in infant shaking. Forens Sci Med Pathol 1, 53–59 (2005). https://doi.org/10.1385/FSMP:1:1:053
Accepted:
Issue Date:
DOI: https://doi.org/10.1385/FSMP:1:1:053