Involvement of Sclera in Lattice Retinal Degeneration: An Optical Coherence Tomography Study.

The aim of the study was to evaluate the local status of the sclera in lattice retinal degeneration. Patients with lattice degeneration, snail-track degeneration, or horseshoe retinal breaks were included. One lesion of a single eye in each patient was captured with cross-sectional optical coherence tomography (OCT) along and across the greatest lesion dimension. The maximum height of scleral indentation was measured and compared between different lesion types and between lattice lesions with and without retinal breakage or local detachment. The correlation between the maximum height of the scleral indentation of lattice lesions and the age of the patients was calculated. Seventy-five eyes of 75 patients (44.4 ± 14.7 years; 35 males and 30 females) were included. OCT showed variable local scleral indentation in 52 out of 55 (94.5%) lattice lesions, in five out of nine (55.5%) snail-tack lesions, and in three out of eleven (27.3%) horseshoe breaks. The maximum scleral indentation within lattice lesions, snail-tack lesions, and horseshoe breaks was 227.2 ± 111.3, 22.0 ± 49.2, and 88.5 ± 48.4 µm, respectively (p < 0.001 for snail-tack lesions and horseshoe breaks compared to lattice lesions). Lattice lesions with retinal breaks and/or local retinal detachment had statistically significantly lower scleral indentation than those without (p = 0.01). The height of the scleral indentation of lattice lesions was positively correlated with patient age (r = 0.51, p = 0.03). In conclusion, scleral indentation is one of the hallmarks of lattice retinal degeneration and may be associated with a reduced risk of rhegmatogenous retinal detachment.

Efficacy and Safety of Cataract Surgery-Assisted Selective Laser Trabeculoplasty: A Pilot Study.

Purpose: To evaluate the intraocular pressure (IOP)-lowering effect and safety of selective laser trabeculoplasty (SLT) with same-day cataract surgery which we named cataract surgery-assisted selective laser trabeculoplasty (CAST) compared to conventional SLT and cataract surgery as standalone procedures. Methods: Patients with primary open-angle glaucoma and cataract were included in this prospective interventional study. All patients received either a CAST procedure, standard SLT, or standard cataract surgery. IOP was assessed at baseline and at months 1, 2, 3, and 6. Topical IOP-lowering medication was canceled during the follow-up if necessary. Results: Twenty-nine, twenty-seven, and thirty eyes received the CAST procedure, SLT, and standard cataract surgery, respectively. There was no statistically significant difference in age, male-to-female ratio, or baseline IOP between groups (P > 0.05). The mean IOP reduction at 6 months after the CAST procedure, SLT, and standard cataract surgery was -7.3 ± 3.8 mmHg, -3.8 ± 3.7 mmHg, and -0.7 ± 3.7 mmHg, respectively (P < 0.001). Eleven out of 29 (37.9%) and 5 out of 27 (18.5%) eyes achieved 30% reduction of IOP after the CAST procedure and SLT, respectively. No eyes achieved 30% reduction of IOP at the end of the follow-up in cataract surgery group. The median number of IOP-lowering medications cancelled after the CAST procedure was 1.0 (range, 0-3). No antiglaucoma medication was cancelled after SLT or cataract surgery. No adverse events were registered in patients who received the CAST procedure. Conclusion: At 6-month follow-up, the CAST procedure had a significantly greater IOP-lowering effect and reduction of topical antiglaucoma medication than SLT or cataract surgery alone.

Photoreceptor outer segment layer contributes to optical coherence tomography signal attenuation beneath neurosensory detachments.

PURPOSE: To establish the factors responsible for attenuation of the optical coherence tomography (OCT) signal beneath the neurosensory detachment (NSD). METHODS: We retrospectively reviewed 33 eyes with acute central serous chorioretinopathy. The thickness of the neurosensory retina, the thickness of the photoreceptor outer segment (PROS) layer, the height of the NSD, and the reflectivity of the underlying retinal pigment epithelium (RPE) were measured at selected points of B-scans exported from 6 × 6 mm OCT angiography protocols. The intensity of the flow signal was measured at the corresponding regions of the choriocapillaris slab. The correlation between the parameters of the NSD and both the reflectivity of underlying RPE and the intensity of the flow signal in the choriocapillaris was calculated. RESULTS: Correlation coefficients between RPE reflectivity and neurosensory retinal thickness, PROS layer thickness, and NSD height were -0.32, -0.64, and -0.25, respectively (p < 0.001). Correlation coefficients between the intensity of the flow signal and neurosensory retinal thickness, PROS layer thickness, and NSD height were -0.24 (p = 0.004), -0.52 (p < 0.001), and 0.13 (p = 0.13), respectively. CONCLUSION: The thickness of the PROS layer is the most significant factor affecting OCT signal at the level of RPE and OCT angiography flow signal in the choriocapillaris beneath the NSD.

Retinal Pigment Epithelium Reflectivity at Leakage Site on Spectral-Domain Optical Coherence Tomography in Acute Central Serous Chorioretinopathy.

PURPOSE: To study the reflectivity of the retinal pigment epithelium (RPE) at the leakage site in acute central serous chorioretinopathy (CSC). METHODS: Twenty-nine patients (24 males and 5 females, mean age 46.1 ± 11.0 years) were included. The mean relative RPE reflectivity and the difference between the maximum and minimum relative RPE reflectivity at the leakage site and control site were measured on cross-sectional optical coherence tomography (OCT) scans. In eyes with pinpoint leakage, cross-sectional OCT scans and corresponding reflectivity profile plots were reviewed by a masked grader for the presence of visible RPE defects and focal depression of relative RPE reflectivity at the leak. RESULTS: Twenty-one (61.7%) and 13 (38.2%) leaks showed pinpoint and diffuse leakage, respectively. The mean relative RPE reflectivity at the leakage site was statistically significantly higher than that of the control site (0.82 ± 0.09 and 0.79 ± 0.12, respectively, p=0.03) in eyes with pinpoint leakage as well as in eyes with diffuse leakage (0.81 ± 0.10 and 0.74 ± 0.13, respectively, p=0.01). The difference of relative RPE reflectivity was statistically significantly higher at the leakage site compared to control site (0.56 ± 0.20 and 0.41 ± 0.06, respectively, p=0.002) in eyes with pinpoint leakage, but not in eyes with diffuse leakage (0.46 ± 0.12 and 0.40 ± 0.07, respectively, p=0.16). On cross-sectional OCT scans visible RPE defects at pinpoint leakage were found in 10 out of 21 (47.6%) cases. Focal depressions of RPE reflectivity corresponding to presumed RPE defects were found in 18 out of 21 (85.7%) cases. CONCLUSION: Leakage in acute CSC is associated with significant local increase of RPE reflectivity.

Status of Choriocapillaris in Fellow Eyes of Patients With Unilateral Retinal Vein Occlusions.

BACKGROUND AND OBJECTIVE: To study the status of the choriocapillaris in fellow eyes of patients with unilateral retinal vein occlusions (RVOs). PATIENTS AND METHODS: Thirty-two healthy eyes of patients with unilateral RVO and 16 eyes of healthy age-matched controls were included. Choriocapillaris flow voids and device-specific choriocapillaris total flow areas were quantified based on 3-mm optical coherence tomography angiography (OCTA) scans and their correlation with the number of resolved para-central acute middle maculopathy (PAMM) lesions on 6-mm OCTA scans was calculated. RESULTS: In fellow eyes of unilateral RVOs and in eyes of healthy individuals, the number of choriocapillaris flow voids was 20.8 ± 5.5 and 13.4 ± 5.4, respectively (P < .001), and choriocapillaris total flow area was 6.0 ± 0.34 mm2 and 6.22 ± 0.13 mm2, respectively (P = .005). The number of resolved PAMM lesions correlates significantly with the number of choriocapillaris flow voids (r = 0.44; P = .002) and with choriocapillaris total flow area (r = -0.52; P < .001). CONCLUSION: Fellow eyes of patients with unilateral RVO demonstrate a substantial decrease of perfusion in choriocapillaris, which correlates with the prevalence of small resolved PAMM lesions. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:23-28.].

SUSPENDED SCATTERING PARTICLES IN MOTION MAY INFLUENCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY VESSEL DENSITY METRICS IN EYES WITH DIABETIC MACULAR EDEMA.

PURPOSE: To study the effect of the suspended scattering particles in motion (SSPiM) on optical coherence tomography angiography (OCTA) vessel density metrics in eyes with diabetic macular edema (DME). METHODS: Thirty-four eyes with DME from 27 patients (16 men and 11 women; 61.4 ± 9.6 years) with DME were included in this retrospective cohort study. Among these eyes, 19 (55.9%) showed the SSPiM artifact on OCTA. All participants received 3-mm and 6-mm optical coherence tomography angiography (OCTA) imaging. Perfusion density and skeletonized vessel density were calculated for the superficial capillary plexus (SCP) and the deep capillary plexus (DCP), and these were compared between eyes with and without SSPiM. Additionally, foveal vessel density in a 300-µm-wide region around the foveal avascular zone (FVD) was evaluated on 3-mm OCTA scans. The main outcome measures were vessel density in the SCP and the DCP. RESULTS: Among the 3-mm OCTA images, there was no statistically significant difference in SCP vessel density in eyes with and without SSPiM (P = 0.98). Vessel density in the DCP (P = 0.001 and P = 0.028 for perfusion and skeletonized vessel density, respectively) and FVD (P = 0.03) on 3-mm OCTA scans were significantly higher in DME eyes with SSPiM than in those without SSPiM. There were no statistically significant differences in vessel density in SCP and DCP between eyes with and without SSPiM based on 6-mm OCTA scans. CONCLUSION: The presence of SSPiM may lead to an overestimation of DCP vessel density in eyes with DME when 3-mm OCTA scans are used for analysis.

Anterior chamber particles are associated with reduction of intraocular pressure after selective laser trabeculoplasty.

PURPOSE: To study the correlation between intraocular pressure (IOP) reduction and the number of hyper-reflective particles appearing in the anterior chamber following selective laser trabeculoplasty (SLT). MATERIAL AND METHODS: In this prospective interventional study, we included primary open-angle glaucoma patients. All participants received a standardised SLT session, which consisted of 100 pulses of 0.9 mJ over 360°. Anterior segment optical coherence tomography (4×4 mm volume scan, 101 horizontal cross-sectional scans) and applanation tonometry were performed before SLT and 15 min, 1 day, 1 week, 1 month and 3 months after. Particles were counted on cross-sectional scans using a standardised algorithm. RESULTS: In this study, we included 25 patients (25 eyes), 14 males and 11 females, with a mean age of 68.9±10.5 and baseline IOP of 21.4±4.5 mm Hg. IOP at month 1 and month 3 after SLT was 18.0±4.0 and 17.4±3.3 mm Hg, respectively. The mean number of anterior chamber particles before and 15 min after SLT was 0.62±0.2 and 7.1±2.0 particles/mm2, respectively (p=0.036). There was a statistically significant correlation between the mean number of anterior chamber particles 15 min after SLT and IOP reduction at 1 month (r=0.62, p=0.03) and 3 months (r=0.71, p=0.01). CONCLUSION: The number of the anterior chamber particles graded using anterior segment optical coherence tomography after the procedure correlates with the IOP-lowering effect of SLT.

Structural en face optical coherence tomography imaging for identification of leaky microaneurysms in diabetic macular edema.

PURPOSE: To study the correspondence between fluorescein angiography (FA) and structural en face optical coherence tomography (OCT) in the identification of leaky microaneurysms in diabetic macular edema (DME). METHODS: Fourteen eyes of eight patients with DME (6 males and 2 females, mean age 67.3 ± 8.5) were included. For all eyes, a 6 × 6 mm structural en face image of the middle retina was obtained and superimposed on a FA image. The reflectivity, capsulation, and association with intraretinal cystic fluid (IRCF) of microaneurysms on en face were evaluated depending on their leaky status on FA. RESULTS: Out of the 320 leaky microaneurysms evaluated, 280 (89.0 ± 8.2%) coincided with those on en face OCT image. Twenty-nine (10.6 ± 6.9%) and 20 (6.5 ± 7.8%) out of all leaky microaneurysms were hyperreflective and demonstrated capsular appearance, respectively. A majority of leaky microaneurysms (97.9 ± 3.2%) were associated with IRCF. From 146 microaneurysms which were found only on en face images, 130 (88.2% ± 15.7%) were hyperreflective, 33 (23.9% ± 15.6%) demonstrated capsular structure, and 13 (9.2% ± 15.0%) demonstrated no associated IRCF. After exclusion of microaneurysms of the inner retina, 95.4 ± 5.4% of leaky microaneurysms were identified on en face image. En face imaging demonstrated 83.5% sensitivity and 89.4% specificity (the area under the curve 0.87) in the identification of leaky microaneurysms. CONCLUSIONS: Structural en face imaging is comparable to FA in identification of leaky microaneurysms in diabetic macular edema. Moderate reflectivity, the absence of capsular structure, and neighboring intraretinal cystic fluid indicate leaky microaneurysms.