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Three Part Question

[In patients with an isolated floater, no photopsia and no change in visual acuity] is [dilated fundoscopy by an Ophthalmologist] required to [exclude retinal tear/detachment or other significant pathology].

Clinical Scenario

A 60 year-old lady presents to the emergency department complaining of a 3 day history of a sudden onset single floater in her left eye with no history of flashing lights or other visual problems. Her visual acuity is 6/6 aided in each eye. Dilated fundal examination of her retina with a direct ophthalmoscope is unable to exclude peripheral retinal pathology. You wonder whether she needs specialist dilated fundal examination by an ophthalmologist to exclude a retinal tear or detachment?

Search Strategy

Medline search from 1951 to 08/2005 using the Dialog Datastar interface.
Dialog Datastar
{(vitreous detachment OR photopsia OR flashing lights OR light flashes OR flashes OR floaters OR visual disturbance OR visual acuity OR vision, low) AND (ophthalmoscopy OR mydriasis OR specialism OR referral OR emergency OR emergencies OR early management) AND (retinal detachment OR retinal perforations OR vitreous hemorrhage OR retinal disease)} limited to papers published in English.

Search Outcome

Altogether 361 papers were returned, 2 papers were found that addressed our particular question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Diamond JP, 1992, England	170 patients;147 with unilateral symptoms of flashes and floaters 23 with bilateral symptoms attending eye casualty over 6 months 27 patients with symptom of isolated single floater Patients categorised according to symptoms and signs	Prospective case study	Patients classified into benign vitreo-retinal disease or potentially sight threatening disease after fundal examination	75.9% incidence of benign vitreo-retinal disease Sight threatening condition found in 41 patients (24.5%), the most important being a retinal break (16.5%)	Small number of patients in the study and with symptom of isolated single floater One junior investigator examining patients with potential to miss retinal breaks. Symptoms can vary according to patient history especially in the elderly
			Correlate symptoms and signs to diagnosis	Only one patient of the 27 with single floater symptomology had a retinal break (3.7%) No significant difference in incidence of retinal breaks in patients with single floater v asymptomatic fellow eyes (3.7% v 1.4%)
Byer NE, 1994, USA	350 patients with diagnosis of acute posterior vitreous detachment examined between 1975 and 1987	Prospective case study	Correlate symptomology and prognosis of posterior vitreous detachment	Of 163 patients who had one to two floaters (without flashing lights) as their presenting symptom, 12 (7.3%) went on to develop retinal tears Of 31 eyes that had retinal tears on initial examination, 4 (13%) had a single floater and no light flashes as their initial symptom	Study starts with a cohort of patients with posterior vitreous detachment and not patients with the symptom of an isolated floater No subgroup analysis to elucidate whether single floater vs multiple floater groups differ in their rate of retinal tear development Relying on subjective history of patient with recall over the previous 3 months. No control group with fellow asymptomatic eyes reported

Comment(s)

The symptom of a sudden onset single floater with or without flashing lights in one eye is a common presentation of posterior vitreous detachment (PVD). There is a small risk of retinal breaks associated with this condition. The two studies have highlighted a small risk of retinal break development in patients who have symptoms of a single floater in their vision but do not agree on the recommended management for this group of patients. The timing for development of retinal tears or detachment following PVD can be variable. As a result there is no consensus as to whether this group of patients can be reviewed safely on a routine outpatient basis.

Clinical Bottom Line

Patients who complain of a sudden onset single floater with no photopsia or change in visual acuity in one eye should merit urgent referral to an Ophthalmologist for a detailed fundal examination.

References

1. Diamond JP. When are simple flashes and floaters ocular emergencies? Eye 1992;6(Pt 1):102-104.
2. Byer NE. Natural history of posterior vitreous detachment with early management as the premier line of defense against retinal detachment. Ophthalmology 1994;101(9):1503-1513.