March 3, 2017 Conference
The majority of rhegmatogenous retinal detachments follow a well-understood pathogenetic sequence first described by Gonin over 100 years ago: progressive vitreous liquefaction, posterior vitreous detachment, retinal tear formation, and, finally, retinal detachment. Gonin also discovered that their cure depended on closing the retinal breaks. Since his time, many methods for closing the breaks have been invented and include those that work on the surface of the eyeball and those that work inside the vitreous cavity. Since rhegmatogenous retinal detachment presents infinitely variable pathology to the surgeon, choosing the optimal approach depends on careful observation and sound clinical judgment.
There is a small but significant minority of patients, however, whose retinal detachments do not have posterior vitreous detachment. These include those caused by atrophic retinal holes in lattice degeneration and those caused by retinal dialysis. In the former, vitreous traction is not an issue, and in the latter it is of minor consequence. Skillfully done scleral buckling procedures are successful in reattaching the retina permanently in close to 100% of these cases and PVR almost never occurs following uncomplicated surgery. Side effects are minimal and cataract never occurs as a result of the surgery.
On the other hand, vitrectomy in eyes with solid, non-detached vitreous is extremely challenging. Once inside the eye what does one do with this solid vitreous? One can attempt to detach the posterior hyaloid. This can be difficult to do in these young patients, and detaching it from the detached retina can cause catastrophic complications. Alternatively, one can leave cortical gel attached posteriorly and try to flatten the retina anyway. Both options are less than ideal and increase the possibility of PVR. Draining the usually very viscous subretinal fluid is hard to do by displacement and could require a posterior retinotomy to get the retina flat. Finally, cataract is inevitable.
Examples of the pathology and pathogenesis of these conditions will be presented and suggestions on their management offered.