|
|
ROPARD Online Education Section Module 2
The intervention for peripheral ablation
recommended by the Retinopathy of Prematurity Cryo Study was five clock hours of
contiguous stage 3 disease or eight clock hours of discontiguous stage 3 disease.
Both of these must be accompanied by plus disease and plus disease is defined as dilated
tortuous arteries and veins in the posterior pole. Plus disease we now know evolves
from the periphery and extends to the posterior pole due to the arteriole venous
communication through the shunt in the junction tissue between the avascular and
vascularized retina. The child may present with findings that are less than
typical. These findings can include a very vascularly active eye with exuberant plus
disease in the posterior pole. Eyes such as this may benefit from laser ablation
even though they may not be at what might be considered by the observer as the standard
stage 3 threshold.
These eyes with extremely active plus
disease suggest an extraordinarily active VEGF eye and down regulation of the VEGF needs
to be achieved in order to preserve any level of vision in this type of eye. The
montage in this module does show such an extremely vascularly active eye. Eyes like
these uniformly go on to retinal detachment and blindness without early treatment.
The anterior segment can show dilated vessels or rubeosis iridis is not frank
neovascularization, but represents again a manifestation of absence of involution of
tunica vasculosa lentis due to the very high level of VEGF. Occasionally, this
tunica vasculosa lentis may make it difficult to get good examination into the posterior
pole or even laser treatment for the peripheral retina. If that is the case,
pharmacologic dilatation of the pupil with a pledeget may be helpful or sometimes pressure
on the globe for scleral depression sometimes will result in breaking the pupillary
aperture open. Again, in these eye it is perhaps more important to use the red diode
than in others to avoid lenticular opacity.
|
