Flashes, floaters, and a field defect
BMJ 2013; 347 doi: https://doi.org/10.1136/bmj.f6496 (Published 04 November 2013) Cite this as: BMJ 2013;347:f6496
All rapid responses
Rapid responses are electronic comments to the editor. They enable our users to debate issues raised in articles published on bmj.com. A rapid response is first posted online. If you need the URL (web address) of an individual response, simply click on the response headline and copy the URL from the browser window. A proportion of responses will, after editing, be published online and in the print journal as letters, which are indexed in PubMed. Rapid responses are not indexed in PubMed and they are not journal articles. The BMJ reserves the right to remove responses which are being wilfully misrepresented as published articles or when it is brought to our attention that a response spreads misinformation.
From March 2022, the word limit for rapid responses will be 600 words not including references and author details. We will no longer post responses that exceed this limit.
The word limit for letters selected from posted responses remains 300 words.
"I propose the following wording":
Chunking and checking: 'What particular concerns did you have today about the 'floaters' in your eye?'
Was this the Christmas edition of the BMj? Have the authors ever tried to perform a ' 10-minute consultation' in primary care? If my GP registrar explained symptoms to patients with such terms as suggested, I might have a few suggestions to them.
In agreement with Edward Herbert's response, I shall be advising my GP registrar, to initially address concerns that the patient might have and then like him would ""not (be) convinced that time spent in general practice assessing confrontation fields" would be time well spent, and furthermore suggest "The important thing is to recognise the symptoms and refer to someone appropriately trained in a short time frame so a proper assessment can be carried out."
I would teach my GP registrar aspects of ' knowing my limitations' and ask the patient to return with any questions after seeing appropriately trained and equipped professionals like Mr. Khan and colleagues.
Competing interests: No competing interests
Khan et al helpfully highlight the symptoms of posterior vitreous detachment and the fact that up to 1 in 6 patients with these symptoms will have a resultant retinal tear. Untreated tears can result in retinal detachment and sight loss. They also stress that dilated fundoscopy is required in all cases. It is also important to ensure that whoever is performing fundoscopy is appropriately trained and uses the appropriate techniques. The majority of negligence cases in vitreo-retinal surgery relate to missed or delayed diagnosis of retinal detachment1.
I conducted a survey of the members of the Britain and Eire Association of Vitreo-Retinal Surgeons in 2009. 77% of respondents felt that slit lamp indirect biomicroscopy (90D lens or equivalent) on its own did not constitute a minimum acceptable standard and that an additional technique either 3- mirror contact lens biomicroscopy or binocular indirect ophthalmoscopy with indentation should be used as a minimum. The American Academy of Ophthalmology preferred practice patterns list indented indirect ophthalmoscopy as an essential part of the assessment.
Natkunarajah at al demonstrated that an experienced retinal surgeon would miss 1 in 10 tears with 90D alone if indented ophthalmoscopy was not done2, and that less experienced observers were more likely to miss signs associated with retinal tears3. The report on the outcomes of the community optometry scheme (PEARS) in Cardiff demonstrated a high rate of missed breaks amongst referrals for uncomplicated PVD, suggesting nearly a quarter of breaks were missed4.
I am not convinced that time spent in general practice assessing confrontation fields with a red pin or looking for a Weiss ring with a direct ophthalmoscope would be well spent. The important thing is to recognise the symptoms and refer to someone appropriately trained in a short time frame so a proper assessment can be carried out. In the era of any willing provider there is a significant risk of permanent avoidable visual loss if those providing this service are not suitably trained or experienced and do not perform a full examination.
1. Mathew RG, Ferguson V, Hingorani M. Clinical negligence in ophthalmology: fifteen years of national health service litigation authority data.Ophthalmology. 2013;120:859-64.
2. Natkunarajah M, Goldsmith C, Goble R. Diagnostic effectiveness of noncontact slitlamp examination in the identification of retinal tears. Eye. 2003;17:607-9.
3. Qureshi F, Goble R. The inter-observer reproducibility of Shafer's sign. Eye. 2009 ;23:661-2.
4. Sheen NJ, Fone D, Phillips CJ, Sparrow JM, Pointer JS, Wild JM. Novel optometrist-led all Wales primary eye-care services: evaluation of a prospective case series. Br J Ophthalmol. 2009;93:435-8.
Competing interests: No competing interests
Re: Flashes, floaters, and a field defect
Although separation of the vitreous from the retina is a common and seemingly physiological event, progression to retinal detachment is fortunately uncommon. The incidence of retinal detachment is roughly 1 in 10,000 of the population though much higher in myopic eyes. Many posterior vitreous detachments (PVD) are either asymptomatic or the person ignores the symptoms. It is common to detect a PVD as an incidental finding in eye clinics when patients present for other reasons. It is fortuitous that most of these do not lead to retinal detachment.
Over my career I have noted, as a useful but not infallible rule of thumb, that flashes of retinal origin are mainly seen in dim light but cerebral eg migraine flashes are well seen in daylight and homonymous.
Competing interests: No competing interests