Reproducibility of Portable OCT and Comparison with Conventional OCT.

Optical coherence tomography (OCT) is an indispensable instrument in ophthalmology; however, some facilities lack permanent OCT devices. ACT100, a portable SD-OCT system, allows for medical examinations at hospitals that do not have OCT and house calls. We investigated the usefulness of ACT100 by examining the reproducibility of retinal thickness measurements in 35 healthy participants with normal eyes using ACT100 and Cirrus. Using two OCTs, the OCT imaging of both eyes of each subject was performed. Macular retinal thickness was evaluated using the average value in nine lesions of the Early Treatment Diabetic Retinopathy Study (ETDRS) circle. Both models captured images in all cases. In the right eye, mean retinal thickness was significantly lower than in the ACT100 group in all regions; however, the measured values correlated well. The intraclass correlation coefficients showed the same high reliability as the Cirrus. The coefficients of variation (CVs) of both models showed little variation and high stability; however, the CV of ACT100 was significantly higher. The left eye was almost identical. Macular retinal thickness measured using ACT100 showed slightly greater variability than that by Cirrus; the reproducibility was good and correlated well with that of Cirrus. This technique is a suitable alternative to conventional OCT.

Impact of local COVID-19 alert levels on rhegmatogenous retinal detachment.

PURPOSE: To investigate the impact of the local alert levels regarding coronavirus disease 2019 (COVID-19) on the clinical patterns of rhegmatogenous retinal detachment (RRD) in Japan. STUDY DESIGN: Retrospective, single-center, consecutive case series. METHODS: We compared two groups of RRD patients, a COVID-19 pandemic group and a control group. Based on the local alert levels in Nagano, five periods during the COVID-19 pandemic were further analyzed: epidemic 1 (state of emergency), inter-epidemic 1, epidemic 2 (second epidemic duration), inter-epidemic 2, and epidemic 3 (third epidemic duration). Patients' characteristics, including symptoms' duration before visiting our hospital, macula status, and retinal detachment (RD) recurrence rate in each period, were compared with those in a control group. RESULTS: There were 78 patients in the pandemic group and 208 in the control group. The pandemic group had a longer duration of symptoms than the control group (12.0 ± 13.5 days vs. 8.9 ± 14.7 days, P = 0.0045). During the epidemic 1 period, patients had a higher rate of macula-off RRD (71.4% vs. 48.6%) and RD recurrence (28.6% vs. 4.8%) than the control group. This period also demonstrated the highest rates compared to all other periods in the pandemic group. CONCLUSION: During the COVID-19 pandemic, RRD patients significantly delayed visiting a surgical facility. They showed a higher rate of macula-off and recurrence compared to the control group during the state of emergency than during other periods of the COVID-19 pandemic, although the difference was not statistically significant due to the small sample size.

Temporal Change in Anterior Chamber Depth after Combined Vitrectomy and Cataract Surgery Using Different Sizes of Intraocular Lens.

This study aimed to investigate the temporal changes in the anterior chamber depth (ACD) and refractive prediction error (RPE) of 6 and 7 mm diameter intraocular lenses (IOLs) after cataract surgery or phacovitrectomy with or without sulfur hexafluoride (SF6) gas. We reviewed 120 eyes (120 patients) and divided them into six groups: three groups of cataract surgery alone and phacovitrectomy (with or without SF6), which were further divided according to IOL diameter (6 and 7 mm) used. We examined the ACD and IOL position using a swept-source anterior segment optical coherence tomograph at 1 day, 1 week, and 1 month postoperatively; and the RPE at 1 month postoperatively. The ACD and IOL position at postoperative day 1 in the SF6 injection groups were significantly smaller than those in the other groups (p < 0.01). At 1 week, the ACD and IOL position of the 6 mm IOL SF6 injection group was smaller than those in the other groups (p < 0.01); thus, complications such as synechia or pupillary capture should be considered in the early postopera-tive period of phacovitrectomy with SF6, especially in the 6 mm IOL. The ACD, IOL position, and RPE at 1 month did not significantly differ among the groups, regardless of the IOL diameter or SF6. In the SF6 injection groups, the ACD and IOL position gradually deepened with less gas.

Evaluating posterior vitreous detachment by widefield 23-mm swept-source optical coherence tomography imaging in healthy subjects.

Posterior vitreous detachment (PVD) is a separation between the posterior vitreous cortex and internal limiting membrane. Although PVD was historically considered an acute event, recent studies using spectral-domain optical coherence tomography (SD-OCT) revealed a gradual progression of PVD in healthy subjects. Although SD-OCT improved PVD studies, the narrow imaging angle and long examination time were problematic to allow wide angle capture. The Xephilio OCT-S1 (Canon), a swept-source OCT (SS-OCT) device, can obtain up to 23-mm of widefield B-scan images in a single acquisition. We used this widefield SS-OCT to quantitatively evaluate the PVD stage in 214 healthy subjects aged 4-89 years and determine whether PVD stages differ between the bilateral eyes of each patient. Age was significantly positively correlated with the overall PVD stage (ρ = 0.7520, P < 0.001). Interestingly, partial PVD occurred in children as young as 5 years, indicating that initial PVD onset may occur much earlier than previously reported. Furthermore, PVD stages of the bilateral eyes were highly consistent in 183 subjects (85.5%). Widefield 23-mm SS-OCT thus revealed that PVD started earlier than anticipated, and age was correlated with the symmetry of PVD stage. Widefield 23-mm SS-OCT may also be clinically useful for the evaluation of diseased eyes.

Micropulse laser trabeculoplasty under maximal tolerable glaucoma eyedrops: treatment effectiveness and impact of surgical expertise.

AIM: To evaluate the effectiveness of micropulse laser trabeculoplasty (MLT) for eyes with open angle glaucoma (OAG) under maximal tolerable glaucoma eyedrops and to assess the effect of expertise performing MLT on its clinical effectiveness. METHODS: Medical records of 42 consecutive eyes of 34 patients diagnosed with OAG who underwent MLT were retrospectively reviewed. The effectiveness was determined using the Kaplan-Meier survival analysis. Failure was defined as an intraocular pressure (IOP) reduction of <20% from baseline, an IOP >21 mm Hg during two consecutive follow-up visits, or surgical intervention for OAG. To determine the impact of MLT surgical expertise on clinical effectiveness, the eyes were divided into two groups according to whether the procedure was conducted by an experienced specialist (defined as a glaucoma specialist who had conducted at least ten MLT procedures) or a less experienced glaucoma specialist. The difference in expertise was determined using a log-rank test. RESULTS: MLT was conducted by three glaucoma specialists. The overall survival rates were 0.76, 0.48, and 0.44 at 1, 3, and 6mo, respectively. The survival rates for MLT performed by a less experienced glaucoma specialist were 0.62, 0.31, and 0.25 (n=21 eyes) at 1, 3, and 6mo, respectively, whereas the survival rates for MLT performed by an experienced glaucoma specialist were 0.90, 0.64, and 0.64 (n=21 eyes) at 1, 3, and 6mo, respectively. The log-rank test showed a significant difference in the survival curves of the two groups (P=0.0061). CONCLUSION: The 6-month effectiveness of MLT for controlling IOP is relatively limited in eyes with OAG using maximal tolerable glaucoma eyedrops. However, its effectiveness may be improved if performed by a glaucoma specialist with sufficient MLT experience.