Functional and perfusion changes associated with silicone oil tamponade after macula-off rhegmatogenous retinal detachment surgery: an optical coherence tomography angiography/microperimetry study.

PURPOSE: The current study utilizes microperimetry and optical coherence tomography angiography (OCTA) to assess the optic nerve head vasculature, retinal microvasculature, and retinal sensitivity before and after silicone oil (SO) removal. METHODS: This prospective observational case series study involved 30 eyes subjected to silicone oil endotamponade. Microperimetry and OCTA were utilized to assess the vascular density (VD) of the macula and optic nerve head, as well as the retinal sensitivity (RS), of the participants preoperatively and 1 month following SO removal. The correlation between the various parameters of OCTA and microperimetry was evaluated. RESULTS: There was a significant improvement in the postoperative best-corrected visual acuity (BCVA) (p-value < 0.001) and the postoperative total RS, which was 6.38 ± 2.34 dB as compared to a mean preoperative total RS of 5.04 ± 2.06 dB (p-value < 0.001) and showing a significant increase in all rings. However, there was no significant difference in the pre and postoperative macular VD. On the other hand, there was a significant increase in the postoperative VD of the whole disk and the peripapillary capillary plexus, p-values < 0.001 and 0.002, respectively. CONCLUSION: The removal of SO resulted in significant improvements in retinal sensitivity, vision, and optic nerve perfusion. However, no significant change was observed in macular VD. CLINICAL TRIALS: gov Identifier: NCT04928196.

Macular vascular features of different types of diabetic macular edema using ocular coherence tomography angiography- a comparative study.

BACKGROUND: To compare the microvascular features of different subtypes of diabetic macular edema (DME) by optical coherence tomography angiography (OCTA). METHODS: A cross-sectional study including treatment-naive patients with DME. Eyes were divided according to optical coherence tomography determined morphology into two groups: cystoid macular edema (CME) and diffuse retinal thickening (DRT), with further subdivision according to the presence of subretinal fluid. All patients underwent 3 × 3 and 6 × 6 mm OCTA scans of the macula to compare the foveal avascular zone (FAZ) area, vascular density (VD) of the superficial (SCP) and deep (DCP) capillary plexus and choriocapillaris flow (CF). Laboratory findings (HbA1C and triglyceride levels) were also correlated with the OCTA findings. RESULTS: The study included 52 eyes, 27 had CME and 25 had DRT. There were no significant differences between the VD of the SCP (p = 0.684) and DCP (p = 0.437), FAZ of SCP (p = 0.574), FAZ of DCP (p = 0.563) and CF (p = 0.311). Linear regression analysis revealed that DME morphology was the strongest predictor for BCVA. Other significant predictors included HbA1C and triglyceride levels. CONCLUSION: The morphology of DME, irrespective of SRF, was most significantly correlated with BCVA in treatment-naive patients and CME subtype could be an independent predictor of poor BCVA in patients with DME.

Evaluation of Higher Order Aberrations and Anterior Segment Parameters Changes After Implantable Collamer Lens Implantation for High Myopia.

Purpose: To evaluate changes in higher order aberrations (HOAs) induced by implantable collamer lens (ICL) implantation in correction of high myopia and to compare the anterior segment parameters before and after surgery. Also, to correlate these parameters with HOAs, the best corrected visual acuity (BCVA) and intraocular pressure (IOP). Methods: This prospective interventional cohort case series study included 40 eyes with high myopia that underwent ICL V4c implantation. They were evaluated pre-operatively and post-operatively at 1st and 3rd month HOAs using Scheimpflug Sirius Camera. The anterior segment parameters were evaluated by optical biometry. Correlations between HOAs, BCVA and anterior segment parameters were evaluated. Results: The mean pre-operative BCVA was 0.67 ± 0.17, while post-operative BCVA was 0.74 ± 0.16 (p-value < 0.001). The spherical equivalent was -13.66 ± 2.23 pre-operatively, while post-operatively it was -0.77 ± 0.65 (p-value < 0.001). The mean pre-operative root mean square (RMS) of HOAs was 0.62 ± 0.11 µm, while mean post-operative RMS in the 1st month was 0.82 ± 0.29 µm (p-value < 0.001). At 3rd month, it was 0.63 ± 0.17 µm (p-value = 0.685). The mean pre-operative anterior chamber depth (ACD) was 3.66 ± 0.26 mm. It decreased in the post-operative 1st month to 3.46 ± 0.30 mm, while in 3rd month 3.45 ± 0.24 mm (p-value < 0.001, < 0.001) respectively. The mean pre-operative anterior chamber angle (ACA) 45.98 ± 8.39 o while, the mean ACA was 31.65 ± 4.14, 31.03 ± 3.74 post-operatively (p-value < 0.001, < 0.001) respectively. There was significant increase in IOP (p-value < 0.001). Conclusion: ICL implantation is safe and effective in correction of high myopia, as HOAs increase at first month post-operatively then, return to the pre-operative level by 3rd month. However, anterior segment parameters show significant changes which may need longer follow up.

Effect of pneumatic vitreolysis in management of patients with symptomatic focal vitreomacular traction.

PURPOSE: To evaluate the efficacy of single intravitreal injection of an expansile concentration of sulphur hexafluoride gas (SF6) in treating patients with symptomatic focal vitreomacular traction (VMT) documented by spectral domain optical coherence tomography (SD-OCT) preoperatively. METHODS: This is a prospective interventional case series including 30 eyes of 29 patients with symptomatic focal VMT evident on SD-OCT. Pre-operatively, mean best corrected visual acuity (BCVA) was 20/125 (range 20/400-20/40). Mean central foveal thickness (CFT) was 382 µm (range 149-576 µm; SD ± 91.88). All eyes received single intravitreal injection of 0.3 mL of 100% SF6 gas. Postoperatively, we performed SD-OCT at one week, one month, and three months for all eyes. Primary outcome measure was release of VMT. Secondary outcome measures were changes in postoperative BCVA andCFT. RESULTS: Overall, VMT release occurred in 24 of 30 eyes by the final follow-up visit (80% final release rate); furthermore, 76.9% of eyes with diabetic maculopathy and 25% of eyes with concurrent epiretinal membrane (ERM) had successful VMT release. VMT release was documented on SD-OCT at an average of 3 weeks (range, 1-12 weeks). The rate of release in phakic eyes was 90% (18 of 20 eyes) versus 60% in pseudophakic eyes (6 of 10 eyes). One patient developed a retinal break at upper nasal retina after two weeks of injection. CONCLUSION: Pneumatic vitreolysis (PVL) with limited face-down position is a viable option for treating focal VMT with few adverse events. Further studies are needed to evaluate its indications, benefits, and risks.

Treatment of Intraretinal Cystic Spaces Associated With Gyrate Atrophy of the Choroid and Retina With Intravitreal Bevacizumab.

PURPOSE: To evaluate the use of intravitreal bevacizumab injections for the treatment of intraretinal cystic spaces associated with gyrate atrophy of the choroid and retina. METHODS: Retrospective chart review of 5 eyes of 3 patients with intraretinal cystic spaces associated with gyrate atrophy and treated with intravitreal bevacizumab injections was performed. Information obtained included history, examination findings, optical coherence tomography (OCT), OCT angiography, fluorescein angiography, and microperimetric findings before and after the injections. RESULTS: The mean age of patients was 11 ± 4.6 years. All patients received three monthly bevacizumab injections. The mean corrected distance visual acuity was 0.27 ± 0.10 at baseline and improved to 0.36 ± 0.12 after the injections (P = .015). The mean central macular thickness was 569 ± 127 µm at baseline and improved to 422 ± 123 µm after the injections (P = .067). Microperimetry and OCT angiography performed in 1 patient before and after the three injections showed improved macular sensitivity and vascular density measurements following the injections. CONCLUSIONS: Intravitreal bevacizumab is safe and effective in the treatment of intraretinal cystic spaces associated with gyrate atrophy. [J Pediatr Ophthalmol Strabismus. 2020;57(6):400-406.].

Evaluation of Corneal Biomechanical Parameters in Psoriasis Patients: A Controlled Study.

PURPOSE: To evaluate corneal biomechanical parameters with an ocular response analyzer (ORA) in patients with psoriasis and compare these parameters with age-matched control subjects. STUDY DESIGN: This was a cross-sectional observational case-control study. METHODS: Thirty eyes of 15 psoriasis patients were included in the study and compared with 30 eyes of 15 control subjects. Corneal biomechanical properties were calculated by ORA. Central corneal thickness (CCT) was measured by anterior-segment optical coherence tomography. The main outcome measures were corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg). For dry-eye evaluation, Schirmer's test was used. RESULTS: Mean CH in the psoriasis group was 10.20±1.55 mmHg and in the control group 10.66±1.36 mmHg (p=0.215). Mean CRF in the psoriasis group was 9.76±1.60 mmHg and in the control group 10.97±1.42 mmHg (p=0.003). Mean IOPcc in the psoriasis group was 14.84±3.43 mmHg and in the control group 16.67±3.17 mmHg (p=0.035). Mean IOPg in the psoriasis group was 13.92±3.35 mmHg and in the control group 16.62±3.10 mmHg (p=0.002). Mean CCT in the psoriasis group was 543.90±37.27 µm and in the control group 551.23±28.63 µm (p=0.392). Schirmer's test results in the psoriasis group were 11.4±1.57 mm/5 min and in the control group 17.5±1.52 mm/5 min (p<0.001). CONCLUSION: Psoriasis affects corneal biomechanical properties with statistically significantly lower corneal biomechanics than normal. CH correlates negatively with disease activity. These corneal biomechanical changes should be considered when determining IOP values and during corneal evaluation for keratoconus-suspected patients.

Evaluation of Central and Peripheral Corneal Thicknesses in Patients with Systemic Lupus Erythematosus.

PURPOSE: To evaluate the corneal pachymetric and topographic parameters of systemic Lupus Erythematosus (SLE) patients using Dual Scheimpflug Imaging. METHODS: This observational cross-sectional controlled study included the right eye of 30 SLE patients and 30 age-matched controls. Corneal measurements were acquired by dual Scheimpflug imaging including anterior and posterior corneal curvatures, central, mid-peripheral corneal thickness (measured at the 5 mm zone) and peripheral pachymetry (measured at the 7 mm zone). SLE disease activity index (SLEDAI) was calculated and correlated with corneal pachymetry. RESULTS: SLE patients had significantly thicker corneal periphery than controls. Mean central corneal pachymetry was 530.4± 27.3 microns (SD) in SLE and 547.5±31.5 microns (SD) in control group, p = 0.032. The corneal periphery - except superiorly - was significantly thicker in SLE patients than controls (p ˂0.001). Nasal peripheral corneal thickness positively correlated with disease activity index SLEDAI (p=0.03). CONCLUSION: SLE patients present with thicker corneal periphery than controls characteristically sparing the superior quadrant. Possible corneal photosensitivity leading to peripheral immune complex deposition as well as flatter posterior corneal surface at the periphery are proposed explanations for these findings.

Retinal Sensitivity before and after Silicone Oil Removal Using Microperimetry.

The purpose of the study is to assess the retinal sensitivity, using microperimetry, before and after silicone removal. It included 22 patients admitted for silicone removal after vitrectomy for macula-off retinal detachment. Patients were divided into 2 groups according to the duration of silicone tamponade: Group A: <3 months (included 10 patients), and Group B: 3-6 months (included 12 patients). Retinal sensitivity was tested, using microperimetry, one day before and one month after silicone removal. The best-corrected visual acuity (in LogMAR) significantly improved postoperatively (0.69 versus 1.06 and 0.69 versus 1.07 in Groups A and B, respectively). The mean intraocular pressure (IOP) was 12.89 ± 1.05 mmHg postoperatively versus 14.89 ± 1.76 mmHg preoperatively in Group A (p=0.011) and was 13.33 ± 1.30 mmHg postoperatively versus 15.33 ± 3.11 mmHg preoperatively in Group B (p=0.008). In Group A, the mean postoperative overall retinal sensitivity was 8.70 ± 2.56 dB versus 5.68 ± 2.00 dB preoperatively (p=0.008). In Group B, it was 9.83 ± 3.36 dB versus 7.00 ± 2.55 dB (p=0.002). No statistically significant difference was found between the two groups as regards improvement in overall retinal sensitivity. We concluded that the overall retinal sensitivity significantly increased following silicone removal in both groups. This trial is registered with ISRCTN43187564.