Aniseikonia following pneumatic retinopexy for rhegmatogenous retinal detachment

Pneumatic retinopexy: an update

Pneumatic retinopexy (PR) is a minimally invasive, non-incisional procedure for repairing uncomplicated rhegmatogenous retinal detachment. It consists of an intravitreal gas injection followed by the maintenance of a postoperative head position and the use of laser or cryopexy to seal the retinal breaks. It was initially indicated for a single or a group of retinal breaks no larger than 1 clock hour involving the superior 8 clock hours in phakic eyes with no proliferative vitreoretinopathy. We aim to perform a narrative review on pneumatic retinopexy since the last major review of 2008, based on a Medline search up to June 20 2021 using multiple search words including pneumatic retinopexy, pneumoretinopexy, retinal detachment, and pars plana vitrectomy. Indications for PR have been expanded and include pseudophakic eyes, eyes with mild PVR, and even breaks in the inferior fundus. Depending on the case selection, PR has a single-operation success rate ranging from 45 to 80%. Despite the lower single operation success rate, the functional outcomes of those eyes repaired successfully by primary PR exceed those of scleral buckling (SB) and pars plana vitrectomy (PPV). Best corrected visual acuity, metamorphopsia scores, mental health scores, and vision-related functioning scores were all better in PR-treated eyes compared to PPV-treated eyes. PR should be strongly considered for eligible patients with a primary uncomplicated rhegmatogenous retinal detachments.

Aniseikonia following intravitreal ranibizumab treatment for branch retinal vein occlusion

PURPOSE

To quantify aniseikonia following intravitreal ranibizumab (IVR) in patients with branch retinal vein occlusion (BRVO) and assess the relationship between aniseikonia and retinal microstructure.

STUDY DESIGN

Prospective observational study.

METHODS

This study included 50 patients undergoing IVR treatment for unilateral BRVO. The degree of aniseikonia and best-corrected visual acuity (BCVA) was examined, and retinal microstructure was assessed with optical coherence tomography (OCT) before and 1, 2, 3, 4, 5, and 6 months after treatment. Based on OCT images, we assessed central retinal thickness (CRT), presence of the epiretinal membrane, and serous retinal detachment (SRD), as well as status of the external limiting membrane and ellipsoid zone.

RESULTS

At baseline, mean aniseikonia was - 1.0 ± 2.5%, ranging from - 11.0 to + 6.0%. Nine out of 50 patients had micropsia (18%), one had macropsia (2%), and 40 had no aniseikonia (80%). After 6 months of treatment, mean aniseikonia was - 0.7 ± 1.5%, ranging from - 4.5 to + 3.5%. BCVA significantly improved after treatment (P < 0.001), but aniseikonia did not change (P = 0.73). In patients with BRVO who had micropsia (≤ - 2.0%) at baseline, mean aniseikonia significantly improved from - 4.8 ± 3.3% to - 0.9 ± 1.4% (P < 0.05). Aniseikonia after treatment significantly correlated with BCVA (P < 0.05) and the presence of SRD at baseline (P < 0.05).

CONCLUSION

Majority of eyes with aniseikonia in BRVO had micropsia. The BCVA as well as the micropsia improved following treatment with IVR for BRVO. BCVA and the presence of SRD were predictors of post-treatment aniseikonia.

Incidence of Clinically Significant Aniseikonia Following Encircling Scleral Buckle Surgery: An Evaluation of Refractive and Axial Length Changes Requiring Intervention

To evaluate the incidence of symptomatic anisometropia and aniseikonia requiring intervention following surgery with combined pars plana vitrectomy (PPV) and broad 276 style encircling scleral buckle (ESB) for the repair of rhegmatogenous retinal detachments (RRD) and to report axial length (AL) and keratometry changes, a retrospective review of consecutive RRD patients treated with combined PPV and ESB between June 2016 until September 2019 was performed. All patients with symptomatic optically induced aniseikonia requiring additional interventions or surgical procedures including clear lens exchanges, secondary intraocular lens implants or contact lenses were documented. Keratometry and AL measurements were recorded for each eye and changes calculated. In total, 100 patients underwent combined PPV, ESB and endotamponade with mean age of 59.47 years (SD 11.49). AL was significantly increased (25.39 mm [SD 1.27] to 26.54 mm [SD 1.16], p = 0.0001), with a mean change of 1.15 mm (SD 0.67). Mean corneal astigmatism increased by –0.95 D (SD 0.51) in control eyes preoperatively and –1.33 (SD 0.87) postoperatively (p = 0.03). Over half of phakic patients (39/61; 64%) developed a visually significant cataract, subsequently undergoing surgery. Six of 100 patients developed symptomatic anisometropia with aniseikonia postoperatively (6%). Four proceeded with clear lens exchange despite absence of visually significant cataract (4%). Two of these initially trialled contact lenses (2%). One was intolerant, while the other decided to proceed with clear lens exchange for convenience. Only one patient (1%), being pseudophakic in both eyes, had persistent anisometropia/aniseikonia. AL and keratometry changes induced by encirclement with broad solid silicone rubber buckles are acceptable and similar to those reported previously using narrow encircling components, being unlikely to induce troublesome symptomatic anisometropia/aniseikonia. Many patients are phakic and develop visually significant cataracts, allowing correction of changes induced with the aim of visual restoration. A minority require more prolonged methods of visual rehabilitation, such as contact lens wear or clear lens exchanges. Caution and appropriate consent should be made in patients that are pseudophakic in both eyes at presentation.

Changes in aniseikonia and influencing-factors following successful macula-off retinal detachment surgery

This study investigated the changes in the severity of aniseikonia after surgery for macula-off retinal detachment (RD), and the relationship between aniseikonia and retinal microstructures. The study included 26 eyes of 26 patients undergoing RD surgery. Visual acuity was measured preoperatively, and at 3, 6, and 12 months postoperatively. Degree of aniseikonia and OCT images were obtained at 3, 6, and 12 months postoperatively. The aniseikonia values (mean ± standard deviation) at 3, 6, and 12 months postoperatively were −5.3 ± 4.2%, −4.4 ± 4.4%, and −3.1 ± 3.2%, respectively. Significant improvement was observed from 3 to 12 months postoperatively (P = 0.001). Twelve months postoperatively, 14 eyes had micropsia, 1 eye had macropsia, and 11 eyes were free of aniseikonia. Stepwise multiple regression analyses revealed that the severity of aniseikonia at 12 months postoperatively was significantly associated with postoperative development of cystoid macular edema (CME) and epiretinal membrane (ERM), as well as area of preoperative RD. In conclusion, although aniseikonia was gradually relieved after RD surgery during a 1-year follow-up period, approximately half of patients had aniseikonia and almost all of them had micropsia. Aniseikonia was associated with presence of postoperative CME, ERM, and area of preoperative RD.

Pneumatic retinopexy: patient selection and specific factors

Pneumatic retinopexy is a minimally invasive, non-incisional procedure for repairing retinal detachment. This procedure is associated with reduced morbidity, reduced cost and faster postoperative recovery compared to pars plana vitrectomy and scleral buckling. Superior visual acuity outcomes have also been reported. Intraoperative complications are primarily related to the intraocular pressure rise caused by gas injection, or the misdirection of the gas. There is a low rate of postoperative complications. Anatomic success rates of over 90% can be achieved when strict selection criteria are applied. However, a number of studies have revealed good outcomes in cases with expanded clinical indications. Pneumatic retinopexy is currently underutilized. With appropriate patient selection, a high success rate can be achieved, and therefore, this procedure has an important role in the armamentarium of the vitreoretinal surgeon.