Mario Zingirian

Indocyanine green angiographic findings in central serous chorioretinopathy

The purpose of this study is to better characterise, on the basis of a large number of cases and follow-up evaluations, choroidal abnormalities recently observed with indocyanine green (ICG) angiography in central serous chorioretinopathy (CSC). Digital ICG videoan-giography was performed in 145 patients with active or inactive, acute or chronic CSC. Forty-eight patients were re-examined in a follow-up period of 6-22 months (mean 10 months). Areas of choroidal leakage attributable to hyperpermeability of the choriocapillaris were found in 98.6% of patients in association with active or resolved pigment epithelial leaks and pigment epithelial detachments. Diffusion of ICG into the choroid was characterised by rapid centrifugal spreading of the dye with a wash-out pattern which was particularly evident in areas corresponding to pigment epithelial detachments. In patients with a long-standing disease, when choroidal hyperfluorescence faded, hypofluorescent spots became increasingly evident revealing pigment epithelial alterations not shown by fluorescein angiography. Areas of choroidal leakage remained unchanged in each patient during the followup period, even when subretinal exudation resolved either spontaneously or after photocoagulation. In 5 eyes we observed the appearance of leakage points on pre-existing areas of choroidal leakage. Zonal hyperpermeability of the choriocapillaris characterises all the evolutional stages of CSC and seems to be the primary alteration of this disease. When it corresponds to pigment epithelial detachments choriocapillaris hypermeability is probably associated with local hyperperfusion.

Learning effect, short-term fluctuation, and long-term fluctuation in frequency doubling technique

PURPOSE To evaluate short-term and long-term fluctuations and learning effects in healthy subjects tested with the frequency doubling technique, which is based on a low spatial frequency and a high temporal frequency stimulus. METHODS Twenty-three healthy adult subjects were consecutively recruited from volunteers, and 20 subjects finished the study. All the visual fields were assessed by the frequency doubling technique, program C-20, full threshold. The frequency doubling technique presents stimuli on a black-and-white video monitor with specialized control circuitry interfaced to a microprocessor. During program C-20, full threshold, 17 points are tested, one round point centrally and 16 square ones in the periphery up to 20 degrees of eccentricity. Each stimulus consists of a 0.25-cycle/degree sinusoidal grating undergoing a 25-Hz counterphase flicker. One eye of each patient was chosen at random. Each subject was tested once in the first session, three times in the second session, and once in the third and fourth sessions. Both short-term and long-term fluctuation were studied either as the average fluctuation value of all the points tested or as a point-to-point fluctuation. To study the learning effect, the results of the first session were compared with those of the second, the third, and the fourth sessions. RESULTS The average mean sensitivity of the three examinations of the second session was 30.4 +/- 1.24 dB, and the average short-term fluctuation of all the subjects was 2.16 +/- 0.5 dB. The short-term fluctuation of each point tested ranged from 1.4 to 3.4 dB. The average mean sensitivity for all the sessions was 32.4 +/- 1.14 dB, with an average long-term fluctuation of 3.23 +/- 0.5 dB, and the long-term fluctuation of each tested point ranged from 2.5 to 4.4 dB. A mild learning effect was found between the first section and the others. CONCLUSION Short-term and long-term fluctuations were similar to those known to occur with the conventional threshold perimetry when they were compared with the literature data. A learning effect was also observed and should be taken into account for the clinical use of this test.

Quality of life in patients with early, moderate and advanced glaucoma.

Purpose To evaluate the quality of life in glaucomatous patients using two different questionnaires: the medical outcomes study 36-item short-form health survey (MOS SF-36) and Viswanathan et al’s questionnaire and to compare these two questionnaires.Methods Seventy-seven patients with glaucoma were consecutively selected. Two force-choice questionnaires were administered to each patient. Viswanathan et al’s questionnaire was related to visual disability and the second was related to the quality of life from the MOS 36-item short-form health survey. Both questionnaires were evaluated among all the considered patients and the results were compared. Then the questionnaire which did the best evaluation was used to test the quality of life in three different subgroups based on the mean deviation of the worse eye. Mann–Whitney non parametric test and Spearman’s r coefficient were used and a P value less than 0.05 was considered to be statistically significant. A linear regression model was used.Results In the entire group (n = 77) the Mean Deviation (MD) was −6.5 ± 6.8 dB (mean ± standard deviation) and Corrected Pattern Standard Deviation (CPSD) was 4.7 ± 4.1 dB. The score of the Viswanathan et al’s questionnaire was 8.3 ± 2.4, while MOS SF-36 score ranged from 60.5% to 100% (mean score %). A significant (P < 0.0001) correlation was found between the score of the Viswanathan et al’s questionnaire and MD (r = 0.79), Pattern Standard Deviation (PSD) (r = −0.68) and CPSD (r = −0.61).Conclusion Viswanathan et al’s questionnaire was more useful than MOS SF-36, both for the score and for the velocity to use. Furthermore Viswanathan et al’s questionnaire was more significantly correlated to visual field MD.

Detection of glaucomatous visual field defect by nonconventional perimetry

PURPOSE To report the correlations among Humphrey Field Analyzer 750 (HFA), high-pass resolution perimetry (HRP), and frequency-doubling technology (FDT) perimetry in glaucoma patients and ocular hypertensive patients. DESIGN Cross-sectional study. METHODS Eighty-two eyes of 82 consecutive patients with primary open-angle glaucoma (POAG) or ocular hypertension were included in this study. One eye of each patient was randomly selected for data analysis. Visual fields were assessed by HFA, HRP, and FDT perimetry. HRP global deviation (HRP-GD), HRP local deviation (HRP-LD), FDT-mean deviation (FDT-MD), and FDT-pattern standard deviation (FDT-PSD) were considered for the analysis. Clinical agreement between HRP and FDT was evaluated. All data were analyzed by Pearson r coefficient when the distribution of the data was normal and by Spearman coefficient correlation when the distribution of the data was not normal. A P <.05 was considered statistically significant. RESULTS Fifty-two eyes (52 patients) were classified as glaucoma and 30 eyes (30 patients) as ocular hypertension. In the entire group, a significant (P >.001) correlation was found between the HFA indices and those of either HRP or FDT. A significant (P <.001) correlation was found between HRP-GD and FDT-MD as well as between HRP-LD and FDT-PSD. In 14% of the glaucomatous patients and in 33% of the subjects with ocular hypertension, FDT and HRP showed different clinical features. CONCLUSIONS Our data suggest that FDT and HRP are useful for detection of early glaucomatous visual field damage.

Pattern dystrophy of the retinal pigment epithelium with vitelliform macular lesion: evolution in ten years

SummaryWe report an unusual case of primary dystrophy of the retinal pigment epithelium (RPE) in which a vitelliform macular appearance was associated with reticular hyperpigmentation resembling the pattern dystrophies of the RPE. The entire evolution of the disease was observed and documented step-by-step during a 10-year follow-up. During the progressive change of the lesions morphologic characteristics of butterfly, reticular and macroreticular dystrophy as well as Bests macular dystrophy could be seen. Pathogenetic relationships between all of these dystrophies of the RPE can be supposed.

Expression of extradomain-B–containing fibronectin in subretinal choroidal neovascular membranes

PURPOSE To investigate the presence of the fibronectin isoform containing the extradomain B (B-FN), a marker-protein of angiogenesis, in surgically excised human choroidal neovascular membranes (CNVM) to evaluate whether B-FN could be used as a therapeutic target for specific antibody-photosensitizer immunoconjugates. DESIGN Laboratory investigation. METHODS The setting was an institutional practice. The study population consisted of 15 eyes (15 patients) with CNVM undergoing membrane excision (four eyes with age-related macular degeneration, seven with pathologic myopia and four with multifocal choroiditis). The control group consisted of eight eye bank eyes (four subjects) without choroidal neovascularization. Light microscopic immunohistochemistry on cryostat sections of tissues was obtained. B-FN was detected by a human recombinant antibody, CGS-1, and compared with immunostaining for endothelial cells with factor VIII-related antigen. The main outcome measure was the presence of CGS-1 positively stained cells or areas of the extracellular matrix. Staining of CGS-1 was scored on a scale from 0 to 3. RESULTS Fourteen of 15 neovascular membranes stained strongly with CGS-1 (score 2 or 3). One membrane from a patient with pathologic myopia was negatively stained (score 0). CGS-1 positive staining was detected around endothelial cells and in the extracellular matrix of CNVMs. The retina of eyes without choroidal neovascularization was negative with CGS-1 in all eight donor eyes, while the choroid contained some weakly CGS-1 positive cells (score 0 and 1, respectively). CONCLUSIONS The extradomain B is abundantly expressed in CNVMs, but its expression is more restricted in eyes harboring no apparent choroidal neovascularization. In the future, B-FN might serve as a target for the delivery of antibody-photosensitizer immunoconjugates to newly developed vessels to enhance the selectivity of photodynamic therapy.

Classification of proliferative diabetic retinopathy

Using panretinal fluorescein angiography, three patterns (A, B, C) of capillary nonperfusion were identified in 308 eyes with proliferative diabetic retinopathy. Statistical analysis showed that there was a significant association with different retinal complications and clinical parameters. Pattern A (83.7%: midperipheral location of capillary nonperfusion) occurs in type I and II diabetes and is associated with early retinal neovascularization and focal macular edema. Pattern B (8.1%: capillary exclusions disseminated on the whole retina) is typical of young type-I diabetics and is complicated by early disc new vessels and ischemic maculopathy. Pattern C (8.1 %: capillary nonperfusion confined to the peripheral retina) is observed in type-I diabetic females and associated with multiple, retinal new vessels, without maculopathy. This study also demonstrated that eyes with pattern B retinal ischemia respond less well to laser treatment than eyes with other pattern types. Various pathogenetic factors could lead to these three distinct types of proliferative diabetic retinopathy.

The Accupational Visual Field: II. Practical Aspects: The functional Visual Field in Abnormal Conditions and Its Relationship to Visual Ergonomics, Visual Impairment and Job Fitness

This second portion of the official report from the IPS Task Committee on the Functional Visual Field describes the effects of age, refractive error and its correction, ocular and neuro-ophthalmic disease, hypoxia, drugs, physical exercise, environmental lighting and noise on the functional visual field. Relationships between the functional visual field and ergonomics are also discussed, particularly with regard to driving, piloting an airplane, control tasks, illumination engineering, optical instruments, visual display units, and the design of spectacles and other devices that partially obstruct or interfere with peripheral vision. A third section examines visual field loss as a form of visual impairment, especially with regard to the definitions of visual disability, low vision and blindness, the prediction of functional capabilities, and the design of treatment regimens. Relationships between visual field properties and job fitness are discussed in a fourth section, with an emphasis on existing regulations and how they might be improved for driving, aviation and other areas. The last report section consists of technical notes pertaining to testing distance, measurement of eye and head movements, assessment of the dynamic functional visual field, and detection of visual field defects within the context of industrial medicine and automobile driver licensing requirements.

Study of the Correlation between Average Values of Optic Disc Parameters and Their Measurement Variability using Stereovideographic Digital Analysis

Purpose of our study was to find whether there is a correlation between average values of optic nerve head parameters and their coefficient of variation for repeated measurements. Disc stereo video images were taken with Topcon Imagenet (IS100) and analyzed with the Optic Disc Analysis program. Eleven normal and 9 glaucomatous eyes were selected. A significant correlation was found for horizontal cup/disc ratio (r = -0.037, p = 0.037) and disc area (r = 0.776, p = 0.027) in intra-observer intra-image repeated measurements. Vertical, horizontal and average cup/disc ratios (r = -0.81, r = -0.74, r = -0.78 p < 0.05) showed a significant correlation for intra-observer inter-image repeated measurements. For inter-observer intra-image measurements, a significant correlation was present for average cup/disc ratio (r = -0.64, p = 0.043). Our data show that bidimensional semiquantitative parameters in use for optic nerve head assessment, analyzed by computerized stereovideography, have an intrinsic measurement variability. The variability is significantly related to the value of the measured parameter only when their reference points are determined manually by the operator.

The macular recovery test after photostress in normal and diabetic subjects

SummaryThe authors present a clinical statistical study on the macular recovery test after photostress in normal subjects and retinopathic and non-retinopathic diabetics. The limits within which the test retains its reliability in predicting the development of retinopathy in diabetics are statistically analyzed.