Fig 1.
Central foveal cross-section of optical coherence tomography (OCT) of a normal eye illustrating the measurements: Inner retina (IR), from the internal limiting membrane to the inner margin of the external limiting membrane (ELM). Inner segment (IS) of the photoreceptor layer, from the inner margin of the ELM to the outer margin of the ellipsoid zone (EZ). Outer segment (OS) of the photoreceptor layer, including the outer photoreceptor segment and the interdigitation zone. The outer retina (OR) is composed of IS and OS together.
Fig 2.
Optical coherence tomography (OCT) images of different eyes representative of the different severity grades of external limiting membrane (ELM) and ellipsoid zone (EZ) impairment. For both structures, grade 1 is defined as a normal and continuous structure, grade 2 as altered but continuous, grade 3 as interrupted and grade 4 as absent. A: ELM and EZ grade 1: Fovea 6 months after re-attachment surgery, where ELM and EZ are continuous and only show regular alterations comparable to normal eyes, with a visual acuity of 0.2 LogMAR. B: ELM and EZ grade 2: ELM and EZ are continuous with subfoveal alterations—very minor in the case of ELM—1 month after surgery, with a visual acuity of 0.4 LogMAR (same patient as in A). C: ELM grade 3 and EZ grade 3, the ELM shows small interruptions and the EZ alterations in the foveal area, 1 month after retinal detachment surgery, with a visual acuity of 0.3 LogMAR. D. ELM grade 3 and EZ grade 4: the ELM (arrow) is interrupted and the EZ is terminated outside the foveal area (arrowhead), 1 month after retinal detachment surgery, with a visual acuity of 0.4 LogMAR.
Fig 3.
Inclusion and exclusion criteria.
Flow chart illustrating the inclusion and exclusion criteria for analysis. Starting from a total of 406 eyes with primary rhegmatogenous retinal detachment from January 2013 to August 2020, 317 eyes showed macular involvement, and 228 of these underwent pars plana vitrectomy with SF6 or C3F8 gas endotamponade, with 168 primary successes after 6 months.
Fig 4.
Visual acuity (VA) indicating progressive visual recovery from baseline before vitrectomy for re-attachment of macula-involving primary rhegmatogenous retinal detachment with vitrectomy and gas. Baseline VA (LogMAR) improved after 1 and 2 months. Whiskers indicate standard deviations and asterisks (*) indicate significant differences compared to baseline (p < 0.001; n = 74 for all three time points).
Fig 5.
Reading acuity (RA) from baseline before surgical repair of macula-involving primary rhegmatogenous retinal detachment with vitrectomy and gas. The small and variable sample sizes with possible bias may explain the lack of statistical significance. Whiskers indicate standard deviations and the asterisk (*) indicates a significant difference compared to 1 month (p = 0.026); n = 11 at baseline, n = 29 after 1 month, and n = 30 after 6 months).
Fig 6.
Exemplary evolution in two instances.
Left column A–C: A patient with foveal detachment reporting visual loss for 14 days and a preoperative visual acuity (VA) of 0.7 logMAR and a reading acuity (RA) of 0.3 logRAD before surgery (A), with good visual and morphologic recovery (ELM 1, EZ 2, VA -0.1, RA 0.0) after 1 month (B), and further morphological improvement after 6 months (ELM 1, EZ 1, VA -0.1, RA 0.0) (C). Right column D–F: A patient with foveal detachment reporting visual loss for 30 days (D), with limited early functional recovery (VA 0.9 logMAR, RA 0.7 logRAD) and morphological improvement (ELM 3, EZ3) (E), and slight but still incomplete recovery after 6 months (VA 0.7 logMAR, RA 0.7 logRAD) and persisting structural alterations (ELM 2, EZ 2) (F).
Fig 7.
Inner and outer retinal height changes.
Change in subfoveal inner (IR) and outer (OR) retina height 1 and 6 months after vitrectomy with gas endotamponade for macula-involving primary retinal detachment. A slight but significant decrease in IR and increase in OR were seen. Mean IR thickness decreased from 219.7 ± 79.8 μm to 206.2 ± 57.6 μm, and OR increased from 75.3 ± 19.5 μm to 83.9 ± 11.8 μm (Friedman test for correlated samples p = 0.014 for IR, and p = 0.0005 for OR, n = 74 at 1 month and n = 73 at 6 months). Whiskers indicate standard deviations, and asterisks (*) indicate significant differences compared to 1 month (p < 0.01).
Fig 8.
Inner and outer photoreceptor height changes.
Change in subfoveal inner (IS) and outer (OS) photoreceptor segment height 1 and 6 months after vitrectomy with SF6 gas endotamponade for macula-involving primary retinal detachment. A slight increase in both IS and OS heights and no obvious changes in the IS/OS ratio may indicate a lack of clinical relevance (p > 0.05 for both). Whiskers indicate standard deviations.
Fig 9.
Change in ELM severity grade after surgical repair for macula-involving rhegmatogenous retinal detachment (miRD). ELM was qualitatively graded in the subfoveal OCT into grade 1: normal and continuous; grade 2: altered but continuous; grade 3: interrupted but recognizable; and grade 4: not recognizable. The graph shows the qualitative recovery of the ELM in OCT imaging after vitrectomy for miRD.
Table 1.
Results of the multiple linear regression analyses.