METHODS: Age, sex, and visual acuity were recorded and spectral domain OCT and ultra-wide-field images of the macula and retina were reviewed in a consecutive series of 74 adults with sickle cell disease.
RESULTS: The median age was 37 years (range 19-73 years) and 36 cases (48.6%) were male. SCM was present in at least 1 eye of 40 cases (54.1%) or in 67 of all eyes (42.3%). SCM prevalence was 54.8%, 62.5%, and 25% for the HbSS, HbSC, and HbS/BThal or other genotypes, respectively. SCM was observed in 41 (39.4%) of the eyes with PSR stages 0, 1, and 2, and in 21 (51.2%) of the eyes with PSR stages 3, 4, and 5, respectively. Mild visual impairment or worse was present in 3 eyes (4.8%) with SCM but this was secondary to other pathology.
CONCLUSION: SCM is a frequent finding in the eyes of adults with sickle cell disease. The prevalence is similar for the HbSS and HbSC genotypes and is not related to the PSR stage. High-contrast distance visual acuity is typically preserved.
METHODS: A cross-sectional, hospital-based study. Fifty-four OSA subjects and 54 controls were recruited. Candidate that fulfil the criteria with normal ocular examinations then proceed with spectrum domain Cirrus optical coherence tomography examinations. ONH parameters and RNFL thickness were evaluated. Apnoea-hypopnoea index (AHI) of the OSA group were obtained from the medical record.
RESULTS: In OSA, mean of average RNFL thickness was 93.87 µm, standard deviation (SD) = 9.17, p = 0.008 (p < 0.05) while superior RNFL thickness was 113.59 µm, SD = 16.29, p ≤ 0.001 (p < 0.05). RNFL thickness fairly correlate with severity of the disease (AHI), superior RNFL with R = 0.293, R2 = 0.087, p = 0.030 (p < 0.05), and nasal RNFL R = 0.292, R2 = 0.085, p = 0.032. No significant difference and correlation observed on ONH parameters. In control group, mean of average RNFL thickness was 98.96 µm, SD = 10.50, p = 0.008 (p < 0.05) while superior RNFL thickness was 125.76 µm, SD = 14.93, p ≤ 0.001 (p < 0.05).
CONCLUSIONS: The mean of the average and superior RNFL thickness were significantly lower in the OSA group compare to control. Regression analysis showed RNFL thickness having significantly linear relationship with the AHI, specifically involving the superior and nasal quadrant.
DESIGN: Prospective cross-sectional study.
METHODS: Consecutive CSC patients were recruited from retina clinic. The reference standard for CNV was determined by interpretation of multimodal imaging with OCTA, structural OCT line scan, fluorescein angiography (FA), indocyanine green angiography (ICGA), ultra-widefield fundus photography and fundus autofluorescence (FAF). Two independent masked graders examined OCTA without FA and ICGA to diagnose CNV. Univariate and multivariate analyses were performed to evaluate factors associated with CNV.
RESULTS: CNV was detected in 69 eyes in 64 out of 277 CSC patients according to reference standard. The two masked graders who examined OCTA had sensitivity of 81.2% (95% Confidence Interval [CI], 71.9%-90.4%) and 78.3% (95% CI, 68.5%-88.0%), specificity of 97.3% (95% CI, 95.9%-98.8%) and 96.2% (95% CI, 94.5%-98.0%), positive predictive values of 82.4% (95% CI, 73.3%-91.4%) and 76.1% (95% CI, 66.1%-86.0%), and negative predictive values of 97.1% (95% CI, 95.6%-98.7%) and 96.7% (95% CI, 95.0%-98.3%). Their mean area under the receiver operating characteristic curve (AUC) was 0.88 with good agreement (Kappa coefficient 0.80 [95% CI, 0.72-0.89]). Flat irregular pigment epithelial detachment on structural OCT, neovascular network on OCTA and ill-defined late leakage on FA significantly correlated with CNV in CSC from multiple regression (P < 0.001, P < 0.001 and P = 0.005, respectively).
CONCLUSIONS: There is discordance between OCTA and multimodal imaging in diagnosing CNV in CSC. This study demonstrated the caveats in OCTA interpretation, such as small extrafoveal lesions and retinal pigment epithelial alterations. Comprehensive interpretation of OCTA with dye angiography and structural OCT is recommended.
METHODS: Cross sectional observational cohort study. Subjects with normal eyes were recruited. Two sets of optical coherence tomography angiography images of macula and optic nerve head were acquired during one visit. Novel in-house developed software was used to count the pixels in each images and to compute the microvessel density of the macula and optic disc. Data were analysed to determine the measurement repeatability.
RESULTS: A total of 176 eyes from 88 consecutive normal subjects were recruited. For macular images, the mean vessel density at superficial retina, deep retina, outer retina and choriocapillaries segment was OD 0.113 and OS 0.111, OD 0.239 and OS 0.230, OD 0.179 and OS 0.164, OD 0.237 and OS 0.215 respectively. For optic disc images, mean vessel density at vitreoretinal interface, radial peripapillary capillary, superficial nerve head and disc segment at the level of choroid were OD 0.084 and OS 0.085, OD 0.140 and OS 0.138, OD 0.216 and OS 0.209, OD 0.227 and OS 0.236 respectively. The measurement repeatability tests showed that the coefficient of variation of macular scans, for right and left eyes, ranged from 6.4 to 31.1% and 5.3 to 59.4%. Likewise, the coefficient of variation of optic disc scans, for right and left eyes, ranged from 14.3 to 77.4% and 13.5 to 75.3%.
CONCLUSIONS: Optical coherence tomography angiography is a useful modality to visualise the microvasculature plexus of macula and optic nerve head. The vessel density measurement of macular scan by mean of optical coherence tomography angiography demonstrated good repeatability. The optic disc scan, on the other hand, showed a higher coefficient of variation indicating a lower measurement repeatability than macular scan. Interpretation of optical coherence tomography angiography should take into account test-retest repeatability of the imaging system.
TRIAL REGISTRATION: National Healthcare Group Domain Specific Review Board ( NHG DSRB ) Singapore. DSRB Reference: 2015/00301.
METHODS: This retrospective analysis was of handheld SD OCT images obtained under a prospective research protocol in children who had established XLRS diagnosis based on genetic testing or clinical history. Three OCT graders performed standardized qualitative and quantitative assessment of retinal volume scans, which were divided into foveal, parafoveal, and extrafoveal regions. Visual acuity data were obtained when possible.
RESULTS: Spectral domain OCT images were available of both eyes in 8 pediatric patients with ages 7 months to 10 years. The schisis cavities involved inner nuclear layer in over 90% (15/16) of eyes in all 3 regions. Retinal nerve fiber and ganglion cell layer involvement was present only in the extrafoveal region in 63% (10/16) eyes and outer nuclear and plexiform layer in few others. In 7 children followed over 2 months to 15 months, the location of schisis remained consistent. Central foveal thickness decreased from the baseline to final available visit in 4/6 eyes. Ellipsoid zone disruption seemed to accompany lower visual acuity in 1/4 eyes.
CONCLUSION: Early in life, the SD OCT findings in XLRS demonstrate differences in schisis location in fovea-parafoveal versus extrafoveal region, possible association between poor visual acuity and degree of ellipsoid zone disruption and decrease in central foveal thickness over time in this group. Furthermore, they illustrates that the pattern of XLRS in adults is already present in very young children, and unlike in older children and adults, those presenting with earlier disease may have a more aggressive course. Further studies in this early age group may provide more insights into treatment and prevention of progressive visual impairment in children with XLRS.
METHODS: 71 investigation sites of sound fissure and naturally occurring NCFC on human extracted premolars were identified and scanned with a swept-source OCT. The teeth were then sectioned bucco-lingually at the investigation sites and imaged using PLM. Two calibrated examiners trained on the B-scan NCFC visual interpretation criteria established for this study, assessed the investigation sites and results were validated against PLM.
RESULTS: Detection sensitivity of B-scan for NCFC when fissures were assessed in totality, or on the slopes or walls separately are 0.98, 0.95, 0.94 and specificity are 0.95, 0.90, and 0.95. One-way ANOVA showed that width measurements of wall loci done with OCT and PLM were not statistically different. However, OCT height measurements of slope loci were statistically bigger with a constant bias of 0.08 mm (of which is not clinically significant) and OCT height measurements of wall loci were statistically smaller (0.57 mm) and Bland-Altman plots indicated presence of proportionate bias.
CONCLUSION: Visual assessment of B-scans with the interpretation criteria resulted in both high specificity and sensitivity and were not affected by loci location. OCT width measurement of wall loci is in agreement with PLM.
CLINICAL SIGNIFICANCE: Unanimous high sensitivity in this and previous studies indicate that visual assessment of B-scans reliably rule out NCFC. Detection accuracy was not affected by loci location. Width of wall loci and/or height of slope loci in OCT B-scan are to be used for monitoring NCFC but not height of wall loci.