Association of Diabetic Lesions and Retinal Nonperfusion Using Widefield Multimodal Imaging

PURPOSE

To evaluate the association of microvascular lesions on ultrawidefield (UWF) color fundus (CF) images with retinal nonperfusion (RNP) up to the midperiphery on single-capture widefield (WF) OCT angiography (OCTA) in patients with diabetic retinopathy (DR).

DESIGN

Cross-sectional study.

SUBJECTS

Seventy-five eyes of 50 patients with mild to severe nonproliferative DR (NPDR) and proliferative DR (PDR) were included in this analysis.

METHODS

ETDRS level and presence of predominantly peripheral lesions (PPLs) were assessed on UWF-CF images acquired with a Zeiss Clarus 700. Single-capture 65°-WF-OCTA was performed using a PlexElite prototype (Carl Zeiss Meditec, Inc.). A custom grid consisting of a central ETDRS grid extended by 2 rings reaching up to the midperiphery was overlaid to subdivide retinal areas visible on WF-OCTA en face images. Retinal nonperfusion was measured in each area and in total. Nonperfusion index (NPI) was calculated from total RNP. On UWF-CF images, the number of microaneurysms, hemorrhages, neovascularizations, and areas with intraretinal microvascular abnormalities (IRMAs) were evaluated using the same grid.

MAIN OUTCOME MEASURES

Association of diabetic lesions with RNP was calculated using Spearman correlations (rs).

RESULTS

Median RNP on WF-OCTA was 0 mm2 (0-0.9), 4.9 mm2 (1.9-5.4), 23.4 mm2 (17.8-37), and 68.4 mm2 (40.8-91.7) in mild, moderate, and severe NPDR and PDR, respectively. We found a statistically significant correlation (P < 0.01) of overall RNP (rs = 0.96,) and NPI (rs = 0.97) on WF-OCTA with ETDRS level. Number of grid-fields affected by IRMAs on CF images was highly associated with NPI (rs = 0.86, P < 0.01). Intraretinal microvascular abnormalities and RNPs had similar topographic distributions with high correlations in affected areas. Eyes with PPLs (n = 43 eyes, 57%) on CF images had a significantly higher NPI (P = 0.014) than eyes without PPLs.

CONCLUSION

The combination of UWF-CF imaging and single-capture WF-OCTA allows precise and noninvasive analysis of the retinal vasculature up to the midperiphery in patients with DR. The presence and extent of IRMAs on CF images may serve as an indicator for underlying RNP, which is more pronounced in eyes with PPLs.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Assessing postoperative toric intraocular lens rotation: comparative analysis

PURPOSE

To investigate the accuracy of 3 distinct postoperative toric intraocular lens (TIOL) rotational stability measurement methods.

SETTING

Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria.

DESIGN

Single-center, prospective, interventional clinical trial.

METHODS

128 eyes of 81 patients with age-related cataract received a hydrophobic acrylic TIOL Clareon CNW0T3-9. To evaluate rotational stability, 3 distinct assessment methods were used: (Rotix) comparing the TIOL axis at the end of surgery (EoS) with 1 week and 6 months postoperatively using reference vessels at the sclera, (Slitlamp) comparing the intended axis (IA) with the axis at 1 week and 6 months using slitlamp photography using the horizontal axis as a reference, and (Casia) comparing the IA with the axis at 1 week and 6 months using the axis determination tool of a swept-source anterior segment optical coherence tomographer (Casia 2).

RESULTS

Mean absolute rotation from EoS/IA to 6 months differed significantly among Rotix (1.33 ± 1.99 degrees [0.01; 19.80]), Casia (2.88 ± 2.64 degrees [0.00; 19.00]), and Slit-lamp (4.38 ± 3.38 degrees [0.02; 19.38]), as indicated by the Friedman test (χ 2 = 71.852, P < .001). Bland-Altman coefficients of repeatability (CoRs) indicated the closest agreement of results between Casia and Rotix, with a CoR of ±3.95 degrees, followed by Slit-lamp and Casia (±6.82 degrees), and finally, between Slit-lamp and Rotix (±7.19 degrees).

CONCLUSIONS

When assessing true TIOL rotational stability, it is imperative to use fixed anatomical landmarks as a reference and establish a baseline at the EoS. When assessing TIOL rotation along the horizontal axis, considering cyclorotation of the eye is crucial and must not be underestimated.

Macular Microvascular Perfusion Status in Hypertensive Patients with Chronic Kidney Disease

To compare retinal microvascular perfusion between the eyes of hypertensive patients with and without chronic kidney disease (CKD), the vessel density (VD) and fractal dimension (FD) of the superficial (SVP) and deep retinal vascular plexus (DVP) were analyzed on 6 × 6 mm fovea-centered optical coherence tomography angiography (OCTA) images of patients with hypertension. The retina was divided into an inner ring (IR) and outer ring (OR) according to the Early Treatment of Diabetic Retinopathy Study grid. The glomerular filtration rate (GFR) was determined and CKD was diagnosed (GFR < 60 mL/min/1.73 m2). Ninety-six eyes from 52 patients with hypertension were included in this analysis. Twenty patients (n = 37 eyes) were diagnosed with CKD. The mean age was 69 ± 11.7 years and 60.4 ± 9.2 years in the CKD group and in the control group, respectively. The univariate model revealed a significant difference in VD between patients without and with CKD in the superficial IR (0.36 ± 0.03 vs. 0.34 ± 0.04, p = 0.03), the superficial OR (0.35 ± 0.02 vs. 0.33 ± 0.04, p = 0.02), the deep OR (0.24 ± 0.01 vs. 0.23 ± 0.02, p = 0.003), and the FD in the SVP (1.87 ± 0.01 vs. 1.86 ± 0.02, p = 0.02) and DVP (1.83 ± 0.01 vs. 1.82 ± 0.01, p = 0.006). After adjusting for age and sex, these differences did not remain statistically significant. Similar results were observed for the FD in the SVP and DVP. In our cohort, patients with hypertension and CKD did not differ from patients without CKD in regard to microvascular perfusion status in the macular area as assessed using OCTA.

Rotational stability and refractive outcomes of a new hydrophobic acrylic toric intraocular lens

PURPOSE

To assess rotational stability and refractive outcomes of a new toric hydrophobic acrylic intraocular lens (IOL).

DESIGN

Single-center, prospective, interventional clinical trial.

METHODS

A total of 130 eyes of 82 patients with age-related cataract and total corneal astigmatism of greater than 1.0 diopters (D) received a hydrophobic acrylic toric IOL Clareon CNW0T3-9. Baseline measurement for rotational stability evaluation was performed at the end of surgery (EOS), with the patient still supine on the operating table, using non-movable vessels as reference landmarks. Postoperative retroillumination pictures were taken at 1 h, 1 week, 1 month and 4-6 months postoperatively. Subjective manifest refraction was assessed at the 6 months follow-up visit.

RESULTS

Final results were obtained in 126 eyes of 80 patients. Mean absolute rotation from EOS to 6 months was 1.33 ± 2.00 [0.01, 19.80] degrees. Rotational stability values from EOS to 1 h, 1 h to 1 week, 1 week to 1 month and 1 month to 6 months were 0.86 ± 0.82 [0.00, 3.90], 1.06 ± 1.94 [0.00, 19.45], 0.47 ± 0.42 [0.00, 2.03] and 0.38 ± 0.40 [0.00, 2.56] degrees. Mean preoperative corneal astigmatism was 1.78 ± 0.83 [1.00, 4.76] D which changed to a mean postoperative refractive astigmatism of 0.33 ± 0.27 [0.00, 1.25] D at 6 months.

CONCLUSION

The Clareon toric IOL presented very good rotational stability with a mean absolute rotation below 1.4° from EOS to 6 months. Only two IOLs rotated more than 5° with none of them requiring repositioning surgery. Refractive outcomes were satisfying with a mean residual refractive astigmatism below 0.50 D.

TRIAL REGISTRATION

Registered at Clinicaltrials.gov NCT03803852 ; on May 17, 2022.