Retinal Displacement after Scleral Buckle versus Combined Buckle and Vitrectomy for Rhegmatogenous Retinal Detachment: ALIGN Scleral Buckle versus Pars Plana Vitrectomy with Scleral Buckle

PURPOSE

To assess the risk of retinal displacement after scleral buckle (SB) versus pars plana vitrectomy with SB (PPV-SB).

DESIGN

Multicenter prospective nonrandomized clinical trial.

METHODS

The study took place at VitreoRetinal Surgery in Minneapolis, Minnesota, Sankara Nethralaya in Chennai, India, and St. Michael's Hospital in Toronto, Canada from July 2019 to February 2022. Patients who underwent successful SB or PPV-SB for fovea-involving rhegmatogenous retinal detachment with gradable postoperative fundus autofluorescence (FAF) imaging were included in the final analysis. Two masked graders assessed FAF images 3 months postoperatively. Metamorphopsia and aniseikonia were assessed with M-CHARTs and the New Aniseikonia Test, respectively. The primary outcome was the proportion of patients with retinal displacement detected with retinal vessel printings on FAF in SB versus PPV-SB.

RESULTS

Ninety-one eyes were included in this study, of which 46.2% (42 of 91) had SB and 53.8% (49 of 91) underwent PPV-SB. Three months postoperatively, 16.7% (7 of 42) in the SB group and 38.8% (19 of 49) in the PPV-SB group had evidence of retinal displacement (difference = 22.1%; odds ratio = 3.2; 95% confidence interval [CI], 1.2-8.6; P = 0.02) on FAF. The statistical significance of this association increased after adjustment for extent of retinal detachment, baseline logarithm of the minimum angle of resolution, lens status, and sex in a multivariate regression analysis (P = 0.01). Retinal displacement was detected in 22.5% (6 of 27) of patients in the SB group with external subretinal fluid drainage and 6.7% (1 of 15) of patients without external drainage (difference = 15.8%; odds ratio = 4.0; 95% CI, 0.4-36.9; P = 0.19). Mean vertical metamorphopsia, horizontal metamorphopsia (MH), and aniseikonia were similar between patients in the SB and PPV-SB groups. There was a trend to worse MH in patients with retinal displacement versus those without retinal displacement (P = 0.067).

CONCLUSIONS

Scleral buckle is associated with less retinal displacement compared with PPV-SB, indicating that traditional PPV techniques cause retinal displacement. There is a trend toward increased risk of retinal displacement in SB eyes that underwent external drainage compared with SB eyes without drainage, which is consistent with our understanding that the iatrogenic movement of subretinal fluid, such as that which occurs intraoperatively during external drainage with SB, may induce retinal stretch and displacement if the retina is then fixed in the stretched position. There was a trend to worse MH at 3 months in patients with retinal displacement.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY MORPHOLOGY AFTER RHEGMATOGENOUS RETINAL DETACHMENT REPAIR: ALIGN Post Hoc Analysis

PURPOSE

To compare foveal avascular zone (FAZ) geometric indices using optical coherence tomography angiography (OCTA) in pneumatic retinopexy (PnR) versus pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). FAZ morphology was assessed as a possible imaging feature of retinal displacement.

METHODS

This ALIGN post hoc analysis included primary fovea-off RRDs that underwent successful PnR or PPV, and performed OCTA, and fundus autofluorescence at (FAF) 3 months postoperatively at St. Michael's Hospital, Toronto, Canada. FAZ area (mm 2 ), axial ratio, circularity, and roundness were measured, and FAF images were assessed for retinal displacement.

RESULTS

Seventy-two patients were included, 78% (56/72) were male mean age was 60 ± 9 years, and 60% (43/72) were phakic. Sixty-five percent (47/72) and 35% (25/72) underwent PnR and PPV, respectively. The mean baseline logarithm of the minimum angle of resolution visual acuity was 1.49 ± 0.76. FAZ circularity was lower after PPV (0.629 ± 0.120) versus PnR (0.703 ± 0.122); P = 0.016. Sixty-six patients had gradable FAF images. Retinal displacement was present in 29% (19/66), 84.2% (16/19) of which had displacement in the macula. FAZ circularity was lower in eyes with displacement in the macula (0.613 ± 0.110) versus those without displacement (0.700 ± 0.124); P = 0.015. There was a moderate negative correlation between 12-month aniseikonia and FAZ circularity(r = -0.262; P = 0.041).

CONCLUSION

FAZ circularity was lower after PPV and in eyes with retinal displacement in the macula. Circularity was negatively correlated with 12-month aniseikonia scores. FAZ circularity may be another imaging feature to consider postoperatively after RRD repair.

A Novel Method of Quantifying Retinal Displacement Using Ultra-Widefield Fundus Autofluorescence Imaging

PURPOSE

To introduce a novel method of quantifying retinal displacement in three dimensions (3D) using ultra-widefield fundus autofluorescence (UWF-FAF).

DESIGN

Prospective clinical cohort study.

METHODS

Patients with primary macula-off rhegmatogenous retinal detachment (RRD) treated with pneumatic retinopexy (PnR) or vitrectomy were included. Masked graders selected corresponding points on retinal vasculature and retinal vessel printings (RVPs) within Zone 1, a circular region centered on the fovea with a radius extending to the optic disc (OD) center. Two-dimensional (2D) UWF-FAF was projected to 3D using OD and foveal coordinates. Vertical, horizontal, and diagonal distances between corresponding vessel and RVPs were calculated. Vector displacement of the RVPs to vessels were averaged.

RESULTS

A total of 170 retinal vessel-RVP pairs were identified from 54 UWF-FAF images. Mean displacement in Zone 1 was 0.36 ± 0.38 mm, with an absolute mean angle of displacement of 94.93 ± 41.48° and directionality of 191.84 ± 97.39°. Mean Zone 1 displacement was 0.44 ± 0.42mm and 0.21 ± 0.27 mm in vitrectomy (n = 35) and PnR (n = 19) eyes, respectively (P = .041), with no differences in mean angle of displacement/directionality.

CONCLUSIONS

A novel method of quantifying the magnitude and direction of retinal displacement is presented, accounting for the spherical 3D curvature of the eye by using corresponding points on retinal vessels and RVPs using UWF-FAF. This provides a 3D vector of displacement agnostic of a singular fixation point such as the optic disc. Accurately quantifying the magnitude and angle/direction of displacement may allow for a better understanding of the mechanisms involved in retinal displacement in various surgical techniques, and a better assessment of the association with functional outcomes.

Perfluorocarbon liquid assisted drainage and tamponade associated retinal displacement: A unifying theory on the etiology of retinal folds, slippage and retinal displacement

PURPOSE

To determine the integrity of re-attachment in a macula-off detachment repaired with pars plana vitrectomy using perfluorocarbon liquid (PFO) assisted drainage and short-term tamponade with no air-fluid exchange and to discuss a unifying theory on the etiology of retinal malappositions including retinal displacement (stretch), retinal slippage and full-thickness macular folds.

OBSERVATIONS

Significant retinal displacement was observed on fundus autofluorescence imaging following retinal detachment repair using PFO, along with significant metamorphopsia and aniseikonia. The retinal displacement was in the exact direction as the flow of subretinal fluid during the PFO assisted drainage.

CONCLUSIONS AND IMPORTANCE

Routine use of PFO to assist with drainage and leaving it in as a short-term tamponade for uncomplicated retinal detachment repair may result in inadvertent retinal displacement as a result of the forced flow of subretinal fluid leading to a stretch of the retina. This case supports a unifying theory on the etiology of retinal malappositions including retinal displacement (stretch), retinal slippage and full thickness macular fold. Retinal malappositions occur because of the flow of subretinal fluid either a) induced by the buoyant force of the tamponade and gravity in a direction related to post-operative head position (often towards inferior periphery) in the case of retinal displacement (stretch) or b) from anterior to posterior during air-fluid exchange in the case of full-thickness macular fold with posterior redundancy and anterior stretch or slippage.

Displacement Following Pneumatic vs Vitrectomy for Retinal Detachment (ALIGN)

This multicenter non-randomized comparative trial demonstrates that PPV is associated with a higher risk of retinal displacement compared to PnR for macula-off rhegmatogenous retinal detachment. Furthermore, retinal displacement is associated with worse aniseikonia.

Understanding the mechanism of retinal displacement following rhegmatogenous retinal detachment repair: A computer simulation model

PURPOSE

Retinal displacement is common following rhegmatogenous retinal detachment (RRD) repair. A computer simulation was developed to assess forces applied by a gas tamponade of various sizes in the setting of pneumatic retinopexy (PnR) versus pars plana vitrectomy (PPV).

DESIGN

Computer simulation model.

METHODS

The contact angle and pressure between the tamponade and the retina were calculated using interfacial tension and the densities of gas and vitreous. A simulation determined the dynamics of fluid motion in the subretinal space and calculated deformations of the retina.

RESULTS

Bulk flow of fluid away from the tamponade in a direction along gravity stretched the retina and caused displacement in the simulations. Extent of displacement is attributable to the subretinal fluid layer thickness, and area of contact and contact pressure applied by the tamponade. Larger gas tamponades have greater contact pressure applied to the retina. Reducing gas bubble size from 93% to 6.25% with PPV versus PnR, there was a 79% reduction in the mean contact pressure (1.4 mmHg-0.29 mmHg), and a 93% reduction in the surface area of contact (11 cm² -0.8 cm² ). Therefore, the contact force applied to the entire retina decreases by 97% from 83 mN (PPV) to 2.9 mN (PnR). The model resembling PnR had more than three times less displacement compared to PPV.

CONCLUSIONS

This model provides a framework to study retinal displacement. Our findings suggest that proportional to their size, gas tamponades stretched the retina by displacing subretinal fluid following RRD repair.

Retinal Displacement Following Pneumatic Retinopexy vs Pars Plana Vitrectomy for Rhegmatogenous Retinal Detachment

Importance

Retinal displacement following rhegmatogenous retinal detachment repair may have consequences for visual function. It is important to know whether surgical technique is associated with risk of displacement.

Objective

To compare retinal displacement following rhegmatogenous retinal detachment repair with pneumatic retinopexy (PR) vs pars plana vitrectomy (PPV).

Interventions or Exposures

Fundus autofluorescence images were assessed by graders masked to surgical technique.

Design, Setting, and Participants

A multicenter retrospective consecutive case series in Canada and the UK. A total of 238 patients (238 eyes) with rhegmatogenous retinal detachments treated with PR or PPV who underwent fundus autofluorescence imaging from November 11, 2017, to March 22, 2019, were included.

Main Outcomes and Measures

Proportion of patients with retinal displacement detected by retinal vessel printings on fundus autofluorescence imaging in PR vs PPV.

Results

Of the 238 patients included in the study, 144 were men (60.5%) and 94 were women (39.5%); mean (SD) age was 62.0 (11.0) years. Of the 238 eyes included in this study, 114 underwent PR (47.9%) and 124 underwent PPV (52.1%) as the final procedure to achieve reattachment. Median time from surgical procedure to fundus autofluorescence imaging was 3 months (interquartile range, 1-5 months). Baseline characteristics in both groups were similar. The proportion of eyes with retinal vessel printing on fundus autofluorescence was 7.0% for PR (8 of 114) and 44.4% for PPV (55 of 124) (37.4% difference; 95% CI, 27.4%-47.3%; P < .001). Analysis based on the initial procedure found that 42.4% (42 of 99) of the eyes in the PPV group vs 15.1% (21 of 139) of the eyes in the PR group (including 13 PR failures with subsequent PPV) had displacement (27.3% difference; 95% CI, 15.9%-38.7%; P < .001). Among eyes with displacement in the macula, the mean (SD) displacement was 0.137 (0.086) mm (n = 6) for PR vs 0.297 (0.283) mm (n = 52) for PPV (0.160-mm difference; 95% CI, 0.057-0.263 mm; P = .006). Mean postoperative logMAR visual acuity was 0.31 (0.32) (n = 134) (Snellen equivalent 20/40) in eyes that initially underwent PR and 0.56 (0.42) (n = 84) (Snellen equivalent 20/72) in eyes that had PPV (-0.25 difference; 95% CI, -0.14 to -0.35; P < .001). Among eyes with displacement, mean postoperative logMAR visual acuity was 0.42 (0.42) (n = 20) (Snellen equivalent 20/52) in those that initially underwent PR and 0.66 (0.47) (n = 33) (Snellen equivalent 20/91) in those that initially underwent PPV (-0.24 difference; 95% CI, -0.48 to 0.01; P = .07).

Conclusions and Relevance

These findings suggest that retinal displacement occurs more frequently and is more severe with PPV vs PR when considering the initial and final procedure used to achieve retinal reattachment. Recognizing the importance of anatomic integrity by assessing retinal displacement following reattachment may lead to refinements in vitreoretinal surgery techniques.

Effects of Muller's muscle-conjunctival resection for ptosis on ocular surface scores and dry eye symptoms

This article evaluates the effects of Muller's muscle-conjunctival resection (MMCR) on ocular surface scores and dry eye symptoms. Forty-six patients were enrolled in the study. Eighteen underwent bilateral upper eyelid skin excision with MMCR and 28 underwent bilateral upper eyelid skin-only excision (control group). The Salisbury Eye Evaluation Questionnaire and an ocular surface evaluation protocol consisting of Schirmer's test, tear break-up time (TBUT), fluorescein and rose bengal corneal staining were performed during the pre-operative consultation and on postoperative days 7, 30, and 90. Improvement in symptoms questionnaire scores from baseline was observed on postoperative day 90 in the blepharoplasty plus MMCR group. There was no change in questionnaire scores in patients who underwent blepharoplasty alone. No between-group difference in Schirmer's test, TBUT, or fluorescein and rose bengal staining was found at any time point. In the blepharoplasty-only (control group), the fluorescein staining score was reduced on postoperative day 30 as compared to baseline, but not on day 90. In this sample, addition of MMCR to upper eyelid blepharoplasty did not worsen ocular surface scores or dry eye symptoms.