Holes and lattices in the retina signify areas of weakness in the retinal layer. Most people with these lesions may remain asymptomatic. However, when the vitreous jelly which fills the eyeball liquefies over these lesions, it may result in some traction on the retina. This manifests as seeing black floaters or flashes of light by the patient.
The traction on the retina may open up the retinal holes or create tears resulting is seepage of fluid underneath the retinal layer detaching it from its original position, what we call retinal detachment. Once the retina detaches, the patient may appreciate a falling curtain like sensation or may not be able to see in a specific area of the visual field. This is a condition which requires surgical intervention at the earliest to preserve vision of the eye.