Abstract
Purpose:
This pilot study was designed to evaluate if a corneal damage could induce inflammatory changes in the Central Nervous System (CNS), more specifically along the trigeminal nerve.
Methods:
The right eye of 9 CD1 mice was causticated with NaOH 1N. After 8 days, the eyes and the ganglions of 6 mice were removed and immunostained for anti-CD45. In vivo high resolution MRI was performed in the remaining 3 mice on a 7T-MRI scanner; maps of the T2 relaxation time were acquired along the entire brain 24hrs after iv. administration of ultrasmall particles of iron oxides (uspio) in order to detect macrophage infiltrate. After imaging, animals were sacrificed, ganglia removed, fixed and stained with Prussian Blue to confirm MRI findings.
Results:
Ocular lesion, as alkali burn, induced a CD45+ leukocyte infiltration both in cornea, as expected, and in the ganglion of the same side (right side). The CD45+ cell increase was statistically significant in comparison to the contralateral ganglion (p<0.01). In vivo MRI detected an increase of contrast agent uptake on the right ganglion after alkali burn on day 8 (+13.5% versus the left one), suggesting an inflammatory activity. Prussian Blue staining confirmed uspio uptake in the right ganglion (the left one was negative), which is related to macrophage (published studies).
Conclusions:
Our data indicate that peripheral injury to the cornea is able to induce an inflammatory response in the CNS. This was further confirmed by in vivo MRI. We suggest this has potential implications for the understanding and treatment of ocular surface disorders.
Keywords: 551 imaging/image analysis: non-clinical •
531 ganglion cells •
557 inflammation