I enjoyed the summary, “Posterior vitreous detachment, retinal tear and retinal detachment are a spectrum of disease” by Johnson and Hollands in their article “Acute-onset floaters and flashes,”1 which is part of CMAJ’s “Five things to know about …” series.
I was a bit concerned by the assertion that “[in] 14% of cases, tractional forces … cause a full thickness retinal tear.” This is simply not true if you consider a “case” to be any patient who presents to his or her primary care physician. The data for this statement come from a meta-analysis coauthored by Hollands.2 The studies used in the meta-analysis are predominantly of patients referred to retina specialists. Thus the “cases” have been preselected. I am afraid that a naive reader may assume that in all patients presenting for initial evaluation to their family physician with only a symptom of new-onset floaters will have a 14% chance of retinal tears. Thus, the many family physicians who read CMAJ may have a significant problem with overreferral of the all-too-common phenomenon of floaters without flashes. I would love to see a study that shows how likely patients with floaters, who present only to their family physicians, are to have a retinal tear. To my knowledge there is presently no such good information. All of the studies in this area are coming from tertiary care or subspecialty settings.