Peripapillary and optic nerve head vessel density of glaucoma and healthy subjects from Afro-Caribbean and European descent: A pilot study.

PURPOSE: To compare the peripapillary and optic nerve head vessel density (PP-ONH VD) between glaucoma patients (all, early, moderated, and advanced) and healthy subjects of Afro-Caribbean descent (AD) and European descent (ED). METHODS: This was a cross-sectional study. One eye was evaluated in 90 subjects, including 66 glaucoma patients and 24 healthy subjects, who underwent PP-ONH VD imaging using SPECTRALIS® Optical Coherence Tomography Angiography (OCT-A). We analysed the superficial vascular complex using the AngioTool version 0.6a software. The correlation between the PP-ONH VD and visual field mean deviation (MD) was evaluated using a scatter plot and Spearman's rho correlation coefficient. RESULTS: Among the healthy subjects, the AD group had a lower superficial PP-ONH VD [43.29±3.25% (mean±standard deviation)] than the ED group (46.06±1.75%) (P=0.016). Overall, superficial PP-ONH VD did not show any significant differences between the total AD and ED glaucoma patients or in the subgroup analyses (early/moderate/advanced) (AD: 32.73±6.70%, 37.11±5.72%, 32.48±5.73%, 27.76±4.74%, respectively; ED: 33.94±6.89%, 38.52±3.82%, 35.56±4.18%; 27.65±6.31%, respectively) (P>0.05 for all). A strong, statistically significant correlation was established between vessel density and mean deviation among AD and ED glaucoma patients (r=0.709 and r=0.704, respectively) (P<0.001 for both). CONCLUSION: This pilot study shows that healthy subjects of AD had lower peripapillary and optic nerve head superficial vessel density than healthy subjects of ED, but no significant differences were found between AD and ED glaucoma groups (all, early, moderate, or advanced).

Comparision of intraocular pressure measured using the new icare 200™ rebound tonometer and the Perkins™ applanation tonometer in healthy subjects and in patients with primary congenital glaucoma. / Comparación entre el tonómetro de rebote IC200 y el tonómetro de aplanación Perkins en sujetos sanos y pacientes con glaucoma congénito.

OBJECTIVE: To compare intraocular pressure (IOP) measurements obtained using the Icare 200™ (IC200) rebound tonometer and the hand-held version of the Goldmann Applanation Tonometer (Perkins™ tonometer, GAT) in patients with primary congenital glaucoma (PCG) and in healthy subjects. MATERIAL AND METHODS: A total of 42 eyes of healthy subjects (G1) and 40 patients with PCG (G2) were analysed. The following clinical data were collected: gender, age, Cup/Disc ratio, central corneal thickness (CCT). IOP was determined in the examination room using the IC200 and GAT tonometers, in the same order. Agreement between both tonometers was determined using the intraclass correlation coefficient (ICC) and Bland-Altman plot. A linear regression analysis was used to establish the IOP was affected by the studied variables. RESULTS: Mean IOP between both tonometers (IC200 minus GAT) was: G1=15.91 (2.57) mmHg vs. 15.06 (2.12) mmHg (mean difference, MD=0.84 (0.50) mmHg; P<.101) and G2=20.10 (6.37) vs.19.12 (5.62) (MD=0.98 (1.36); P=.474). Excellent agreement was found between IC200 and GAT in both groups (ICC=G1: 0.875 (95% CI; 0.768-0.933; P<.001); G2: 0.924 (95% CI; 0.852-0.961; P<.001), and there was a statistically significant correlation between the IOP difference measured with IC200 and GAT and CCT in G1 (B=0.021; 95% CI; 0.005-0.037; P=.008), but was not statistically significant in G2. CONCLUSION: There was excellent agreement between the IC200 and GAT tonometers, both in healthy subjects and PCG, with a trend to overestimate IOP when measured with IC200. There was no influence by CCT on IOP measurements in patients with PGC.

Agreement between slit lamp examination and optical coherence tomography in estimating cup-disc ratios.

PURPOSE: To compare optical coherence tomography (OCT) cup-disc ratio measurements with those estimated by two independent examiners using the slit lamp in an evaluation of the optic nerve head (ONH). METHODS: In 47 eyes each of 47 patients with glaucoma and 47 healthy subjects, the ONH was examined using the slit lamp with a 78 D lens. Two examiners subjectively determined the cup-disc area ratio (A-CDR), the horizontal cup-disc ratio (H-CDR), and the vertical cup-disc ratio (V-CDR). These measurements were compared to objective OCT readings obtained by a third examiner blind to the slit lamp results. RESULTS: For the three variables determined, correlation indices between the OCT readings and the two sets of slit lamp measurements were significantly higher for the glaucoma group than the control group. In the patients with glaucoma, the OCT tended to underestimate A-CDR and overestimate H-CDR. For both these variables, Bland-Altmann analysis revealed significant differences between the two methods that persisted across the whole range of CDRs examined. In contrast, differences in V-CDR varied with disc size. CONCLUSIONS: The OCT is a diagnostic tool that provides a complete automatic evaluation of the ONH. However, its measurements vary significantly from those obtained in subjective evaluations performed by experienced ophthalmologists.

Pigment dispersion syndrome associated with optic nerve melanocytoma.

CASE REPORT: A 60-year old patient was referred for cataract surgery. The examination showed retrokeratic pigment in the left eye, which had an intraocular pressure of 24 mm Hg. The funduscopy showed a brown lesion on the left optic disk, with adjacent vitreous seeding of pigment. The patient was thus diagnosed with secondary pigment dispersion syndrome due to optic disk melanocytoma. DISCUSSION: Although melanocytoma is most commonly a benign, stationary tumor, it may present with major complications leading to significant visual loss. A patient with melanocytoma of the optic disk should be examined periodically.

Corneal Segmentation Analysis Increases Glaucoma Diagnostic Ability of Optic Nerve Head Examination, Heidelberg Retina Tomograph's Moorfield's Regression Analysis, and Glaucoma Probability Score.

Purpose. To study whether a corneal thickness segmentation model, consisting in a central circular zone of 1 mm radius centered at the corneal apex (zone I) and five concentric rings of 1 mm width (moving outwards: zones II to VI), could boost the diagnostic accuracy of Heidelberg Retina Tomograph's (HRT's) MRA and GPS. Material and Methods. Cross-sectional study. 121 healthy volunteers and 125 patients with primary open-angle glaucoma. Six binary multivariate logistic regression models were constructed (MOD-A1, MOD-A2, MOD-B1, MOD-B2, MOD-C1, and MOD-C2). The dependent variable was the presence of glaucoma. In MOD-A1, the predictor was the result (presence of glaucoma) of the analysis of the stereophotography of the optic nerve head (ONH). In MOD-B1 and MOD-C1, the predictor was the result of the MRA and GPS, respectively. In MOD-B2 and MOD-C2, the predictors were the same along with corneal variables: central, overall, and zones I to VI thicknesses. This scheme was reproduced for model MOD-A2 (stereophotography along with corneal variables). Models were compared using the area under the receiver operator characteristic curve (AUC). Results. MOD-A1-AUC: 0.771; MOD-A2-AUC: 0.88; MOD-B1-AUC: 0.736; MOD-B2-AUC: 0.845; MOD-C1-AUC: 0.712; MOD-C2-AUC: 0.838. Conclusion. Corneal thickness variables enhance ONH assessment and HRT's MRA and GPS diagnostic capacity.

[Correlating cup-to-disc ratios measured by HRT-III, SD-OCT and the new color imaging Laguna ONhE procedure]. / Correlación de la relación excavación/papila óptica medida mediante HRT-III, SD-OCT y el dispositivo de colorimetría fotográfica Laguna OnhE.

OBJECTIVE: To examine correlations between cup-to-disc (C/D) ratios determined by the new Laguna ONhE (optic nerve hemoglobin) color imaging procedure, spectral domain optical coherence tomography (OCT), confocal scanning laser tomography using Heidelberg retina tomography (HRT), and examining retinal images. METHODS: C/D ratio measurements were made on 154 eyes of 154 subjects (52 healthy controls, 36 with ocular hypertension and 66 with primary open-angle glaucoma) using the Laguna ONhE, HRT-III (Heidelberg Engineering) and OCT Spectralis (Heidelberg Engineering) instruments and photographs of the optic disc were examined by a blinded observer (experienced glaucoma specialist). RESULTS: Global intraclass correlation coefficients (ICC) were: 0.379 (95% CI: 0.233-0.508) for Laguna ONhE-HRT, 0.621 (95% CI: 0.513-0.709) for Laguna ONhE-OCT, and 0.558 (95% CI: 0.398-0.678) for the Laguna ONhE-observer, indicating significant agreement in each case (P<.001). The highest ICC was recorded for OCT- observer (0.715; 95% CI: 0.605-0.795). CONCLUSIONS: C/D ratios measured using the Laguna ONhE procedure correlated well with OCT measurements and retinography measurements made by an experienced observer. Best correlation was observed for OCT versus observer measurements. Agreement was good between the Laguna ONhE, OCT and observer measurements, and was somewhat lower between HRT and the remaining procedures.

[Paradoxical cessation in a case of Charles Bonnet syndrome]. / Cese paradójico de un caso de síndrome de Charles Bonnet.

CASE REPORT: 78-year-old male patient diagnosed with Charles Bonnet syndrome (CBS) showing secondary visual deficit toward end-stage glaucoma. He progressed to amaurosis, with an abrupt disappearance of hallucinations in parallel to the loss of residual vision. DISCUSSION: The paradoxical cessation of CBS occurs when the patient loses residual vision and progresses to amaurosis. The lack of stimulation, both in the corresponding retina and the cortex, lead to the disappearance of hallucinations because the desafferented and hyper-excited neurons lose the necessary stimulus that triggers CBS.