Face-down positioning better after detached retina repair

Face-down positioning is associated with a reduction in certain complications following macula-involving retinal displacement (RD) repair, according to researchers.

“To our knowledge, this is the first study to systematically examine retinal displacement or postoperative distortion at different points after RD repair,” wrote Edward J. Casswell of Moorfields Eye Hospital, London, UK, and colleagues. They published the finding in JAMA Opthalmology.

While macula-involving rhegmatogenous RD repair usually succeeds from an anatomical point of view, as many as 89% of patients experience postoperative distortion. Vitreoretinal surgeons advise various positions after this procedure, but with little evidence to show that one is better than another.

To fill this gap, Mr Casswell and colleagues randomly assigned patients to either face-down or support-the-break positioning, and they were immediately placed in the positions. Support-the-break positioning depended on the location of retinal breaks. They positioned patients with superior breaks upright and those with nasal, temporal or inferior breaks on the contralateral cheek.

The researchers provided the face-down group with an inflatable travel pillow during the first 24 hours. After that, they positioned all the participants in the support-the-break regimen for a further 6 days.

They asked the patients to hold their positions for at least 50 minutes of every hour and throughout the night, and also asked them to complete a positioning and adverse events diary. The researchers recruited 262 patients but excluded those with retinal redetachment. Of the 239 who completed the study, 171 were male and the mean age was 60.8 years.

Support-the-break risks higher

At 8 weeks, analysis of the 103 gradable images in the support-the-break group revealed a 94% greater risk of retinal displacement. At 6 months, 77% more of the patients in the support-the-break group had retinal displacement compared with the face-down group.

Examining the variables, the researchers found that neither extent of retinal detachment; route of drainage; involvement of superior quadrants; duration of visual loss; preoperative lens status; nor gas tamponade were associated with retinal displacement at 6 months.

At both 8 weeks and 6 months postoperatively, the degree of displacement was also greater in the support-the-break group. After 6 months, the support-the-break group had 0.7 more quadrants and 0.42 more fundal degrees of retinal displacement than the face-down group.

Noting a reduction in both D chart and weighted D chart scores in both groups between 2 months and 6 months, the researchers speculated that distortion may resolve over time. “It has previously been suggested that the ghost vessels may move closer together over time,” they wrote.

Visual acuity

The researchers found no statistically significant differences in best-corrected visual acuity in distortion scores or in quality of life scores between the two groups. However, they noted an increased rate of binocular diplopia in the support-the-break group, which they attributed to the increased amplitude of displacement observed in this group, impairing patients’ ability to vertically fuse images.

Although they did not detect a statistically significant difference in best-corrected visual acuity, the researchers speculated that there were not enough patients in their study to detect that or a difference in distortion between the two groups.

They did find that the amplitude of retinal displacement was associated with higher distortion scores and worse visual acuity. “We think this highlights the importance of avoiding retinal displacement given its potential consequences on visual function,” they said.

They recorded a higher rate of transient neck pain or stiffness in the face-down group. Also, the face-down group had a higher intraocular pressure (IOP) and the researchers speculated that this could result from residual intraocular fluid containing inflammatory mediators being displaced toward the iridocorneal angle, leading to inflammation and a delayed elevation in IOP.

Previous studies exploring the benefits of the face-down position have either been retrospective or have not formally evaluated displacement or distortion, the researchers reported. They have either found no difference between positions, or shown an advantage for the face-down position.

The study did not examine “no-position” or a macula-dependent position, which is advocated by some surgeons, the researchers acknowledged.