Purpose: The purpose of this report is to describe the occurrence of a retinal tear, pre-retinal
and vitreous hemorrhages after a session of WBV training.
Case Report: A 59-year-old male presented with a chief complaint of floaters and a moving shadow
OS within a few hours of completing a session of WBV training. A temporal retinal
tear, 1+ vitreous hemorrhage, and pre-retinal hemorrhage was found OS. His vision
was 20/30 OD and 20/30-2 OS. His health history was positive for hyperlipidemia, hypertension,
and DMII without ocular manifestations. The retinal tear was treated using laser photocoagulation.
At the 4-month follow up there was resolution of the vitreous and pre-retinal hemorrhage
with no new tears seen.
Vibration and shaking have been shown to have effects
on various tissues in the human body 1. Vibration can be caused by occupational
environment (e.g. pneumatic drill operation), trauma (e.g. shaken baby syndrome),
and WBV training exercise. Some documented findings of adverse vibration after-effects
include vasospastic diseases in hands 2 as well as ocular effects such as
increased pigment within the trabecular meshwork, vitreous liquefaction 3
and retinal and vitreous bleeding in child abuse 4. In current literature,
there has only been two documented cases of vitreous hemorrhage following WBV exercise 5,6.
Both of these papers suggest a high probability of correlation between WBV training
and subsequent vitreous hemorrhage.
Our patient had utilized a WBV training device
for 60 seconds a few hours before the onset of his ocular symptoms. The device used
by our patient included a footplate on which the user can position him or herself
that vibrates at a frequency up to 25-50 Hz. One study details how mechanical resonant
frequency can affect the eye, outlining different vibration frequencies between 5
to 50 Hz with secondary transmission frequency to the eye 7. This study
suggests the approximate resonant frequency of the eye to be 18 Hz and a partial resonance
of 10-12 Hz for the vitreous body 7.
Conclusion: One possible pathogenesis of the retinal tear and vitreous hemorrhage was instigated
by the vibrations from the machine transmitting a vibratory force to the eye and vitreous.
In various types of vitreous-induced retinal tear formation, it is thought that vitreous
movement causes shear injury to the retina at the vitreous base. The tear in our patient
occurred at the vitreous base. The vibratory force probably caused his retinal tear
and vitreous hemorrhage since the onset of symptoms was within 24 hours of using the
WBV training device. We believe our patient and those in the Bertschinger and Gillan
papers strongly suggest that high-force vibration training may cause retinal tears
in susceptible persons. Though our patient is the third documented case of vitreous
hemorrhage following WBV training, he is the first to show a close association of
a retinal tear and vitreous hemorrhage with WBV training.