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.

Pleomorphic adenocarcinoma of the ciliary epithelium: a clinicopathological, immunohistochemical, ultrastructural, DNA-ploidy and comparative genomic hybridization analysis of an unusual case.

PURPOSE: To describe detailed phenotypic and genotypic analysis of a pleomorphic adenocarcinoma of the ciliary epithelium (CE). CASE REPORT: An 86-year-old white woman developed an enlarging mass protruding from her previously eviscerated left eye 2 months postoperatively. Based on light and ultrastructural microscopy, the final diagnosis was a pleomorphic adenocarcinoma of the ciliary epithelium (CE). DISCUSSION: Cell proliferation indices confirmed the unusually rapid growth rate of this tumor; the peridiploid DNA content might explain the relatively low incidence of distant metastases. An imbalance of the chromosome 6 was also found by Comparative Genomic Hybridization (CGH).

Computerized system for static and kinetic automatic perimetry.

A new automatic perimeter has recently been developed under the supervision of the Perimetry Study Group of the Genoa University Eye Clinic. The main characteristics of this instrument are the following: projected targets; accurate calibration of stimulus size and shape; preliminary measurement of visual acuity and pupillary diameter; automated fixation control based on an optimized television system; static, kinetic, and mixed procedures; screening and diagnostic threshold and suprathreshold strategies; standard and non-standard parameters for stimuli, background, and procedures; user-friendly software; large disk memory for data storage and analysis.

Evaluation of amblyopic scotoma by electrophysiological examinations and computerized perimetry.

To evaluate amblyopic scotoma and the most affected neural cells in suppressive phenomena, eight patients with deep amblyopia from strabismus (visual acuity of the amblyopic eye between 4/50 and 2/10) underwent a pattern electroretinogram (PERG), pattern visual evoked potential (VEP), and event-related potential (ERP) from visual stimuli, and computerized perimetry. The results of stimulation of the amblyopic eye, the leading eye and the leading eye penalized by Ryser filters were compared statistically. Computerized perimetry was used to quantify the depth and amplitude of the amblyopic scotoma. All electrophysiological potentials were reduced in amplitude and the implicit times of VEP and ERP were longer when stimulating the amblyopic eye compared to the leading eye. Only in PERG the penalization induced major changes. Our data suggest that the important suppressive phenomena present in the squint amblyopic eye involve not only the occipital cortex, but also the cognitive areas.

Fundus angiography with fluorescein-labelled peptide fraction from bovine factor VIII: correlation with histologic findings.

A peptide fraction (VUEFFE) obtained from bovine factor VIII, with a high affinity for vessel endothelium, was bound to fluorescein and used for angiography in rabbits. Several eyes had undergone laser photocoagulation on the retina. The location of the dye was studied histologically with fluorescence microscopy on the enucleated, freeze-dried eyes. The angiographic and histologic findings were compared with findings obtained using sodium fluorescein. Fluorescein-labelled VUEFFE gave a longer lasting fluorescence of the retinal vessels with histologic evidence of dye deposition on the vessel wall. It also showed marked affinity for the photocoagulated tissues, giving intense and prolonged staining of the laser burns. Possible clinical applications are discussed.

The nasal step in normal and glaucomatous visual fields.

We used an original method of kinetic and static analysis to examine the nasal visual field. When the nasal step is less than 4 degrees wide and its depth is less than 0.5 log units it may be merely a physiological sign of the anatomic and functional asymmetry of the retina. Sometimes it is an artifact. The nasal step can also be a glaucomatous defect. In this case it is often an early sign and it is wider than 4 degrees and its depth is greater than 0.5 log units. Because of its typical shape and invariable location it is easy to discover by kinetic perimetry and easy to check by static perimetry. If it is an early glaucomatous defect, it can be reversed. In practice the nasal step is an early and characteristic glaucomatous field defect like the isolated scotomas in the Bjerrum area, and it is easily detected and can be used as a sensitive marker in the follow up of glaucomatous damage.

[Automated perimetry and macular diseases]. / Périmétrie automatisée et pathologie maculaire.

The macular programs of computerized perimetry are very useful for the functional quantitative assessment of all kinds of maculopathy and for monitoring their clinical evolution. They often help the ophthalmologist in making decisions concerning critical situations.

[Reversibility of visual field defects in primary open-angle glaucoma]. / La réversibilité des déficits périmétriques dans le glaucome primitif à angle ouvert.

The course of the glaucomatous visual field seems to be best followed by computerized perimetry which allows threshold evaluation in a great number of locations and statistical analysis of the results. To determine the visual field defect reversibility, 16 patients (27 eyes) affected by uncontrolled open-angle glaucoma underwent visual field analysis before and after prescription of a new medical therapy. To avoid the "learning effect" and to decrease the influence of the heterogeneous component of long-term fluctuation, the visual field examination was repeated within 48 hours whenever a change in sensitivity was detected. In addition a total of 10 normal eyes in 10 patients were tested as a control group. A statistically significant threshold improvement was demonstrable after one week of therapy in 31.7% of the eyes.

[New occult choroidal vessels in age-related macular degeneration]. / Néovaisseaux choroïdiens occultes au cours de la dégénérescence maculaire liée à l'âge.

We studied the clinical characteristics and the natural course of occult choroidal new vessels (CNV) in 78 eyes with age-related macular degeneration (AMD). Cases were included in 2 groups characterized respectively by ill-defined subretinal ooze (group 1) and serous detachment of the retinal pigment epithelium (RPE) with adjacent areas of mottled pigmentation (group 2). Both these forms of occult CNV showed to have a slower evolution compared to the classic CNV occurring in AMD, but they also led to disciform scar and severe visual loss. Occult CNV of group 2, contrary to those of group 1, were often multifocal and extrafoveal. They had a greater tendency to hemorrhages and a faster and less gradual progression to fibrovascular scarring and visual loss. Fluorescein angiography showed choroidal filling delay in the macular region of 47% of eyes of group 1. A perfusion defect of the macular choroid could be the basis of the low perfusion pressure and the consequent low activity of CNV with the angiographic pattern of ill-defined ooze.

[Senile macular degeneration: surgical management and histopathologic features]. / Dégénérescence maculaire sénile: traitement chirurgical et aspects histopathologiques.

Choroidal neovascularization often complicates senile macular degeneration; argon and krypton laser photocoagulation are very useful to stop visual acuity decrease caused by extrafoveal choroidal neovascular membrane (NVM) in a large group of patients. Unfortunately, in a large number of cases, NVM causes haemorrhagic serous detachment, disciform scar and, sometimes, vitreous hemorrhage. In these patients it is impossible to perform laser treatment. A three ports pars-plana vitrectomy has been performed for the treatment of intravitreal hemorrhage in a case of haemorrhagic disciform lesion and in two cases of extensive subretinal haemorrhage secondary to subretinal NVMs. Posterior pole focal retinotomies have been created to remove the NVMs in order to prevent further hemorrhages; an internal tamponade has been performed and the retinotomies closed with endophotocoagulation or endocryo. The specimen of the membranes, stained for light microscopy, have been studied. During the months of follow-up (9 months) no subretinal membrane no retinal detachment developed but fibrosis at the retinotomy sites led to traction on the macula. The functional aim of this surgery is limited to the restoration of a clear vitreous and to a reduction in the diameter of the central scotoma in the cases of a recent subretinal haemorrhage.

[Chronic mucosynechial pemphigoid: so-called ocular pemphigus]. / Chronisches schleimhautsynechienbildendes Pemphigoid: der sogenannte "Pemphigus ocularis"

The so-called ocular pemphigus is an oculocutaneomucosal disease, the clinical manifestations of which have been recognized for over a century while its recognition as a nosological and histopathological unit is quite recent. The clinical picture in the eye consists essentially of progressive scar contraction which, preceded by a transient bullous phase, leads to symblepharon, entropion and trichiasis. Corneal complications, such as bullous eruption, erosions, proliferation of vasculoconnective tissue, supervene later. The final appearance is that of complete xerosis with total symblepharon producing a typical 'statute eye'. This local process may be accompanied by bullous lesions of the skin and mucous membranes but the general condition of the patient invariably remains good. In the advanced stages of the disease the appearance is described as 'pemphigoid facies'. The nosological place of ocular pemphigus has been a matter of debate. At various times it has been identified with pemphigus vulgaris, dermatitis herpetiformis of Duhring-Brocq, erythema multiforme of Hebra, Stevens-Johnson syndrome, syphilitic dermatitis bullosa and other bullous dermatoses. At present the condition is universally recognized as a clinical entity, referred to as chronic mucosynechial pemphigoid (CMSP). The anatomopathological picture is quite peculiar. The elementary lesion is a sub-epidermic bulla, hence easily distinguished from that of pemphigus vulgaris, which is situated in the Malpighian layer. This difference applies to the lesions of the skin as well as to those of the mucous membranes including the conjuctiva. In the conjunctiva, epithelial changes suggestive of its epidermization were demonstrated. The Malpighian layer shows a high glycogen and DNA content with overall reduction in enzyme activity. The dermis shows infiltration by lymphocytes, histiocytes and plasma cells, and a considerable increase in hyaluronic acid content. There are many areas of dermoepidermal separation with formation of bullae and the basal membrane is often missing. In some cases, in the centre of the bullae, we were able to demonstrate one or more lumps, consisting almost exclusively of hyaluronic acid, probably filtered in from the dermis across the altered basal membrane. Similar changes are met with also in other mucous membranes, that of buccal cavity in particular, even in ostensibly healthy areas. The histological and histochemical findings are sufficiently typical to justify early diagnostic biopsy in all suspected cases. The aetiology of the CMSP still remains debated. Two theories are under consideration at the moment, viral and autoimmune. The main argument in favour of the viral theory is that a cytopathogenic agent can be isolated from the blood of patients with different dermatoses of the pemphigus group, including the CMSP, whose cytotoxic activity can be passed through and potentiated by passage in cell cultures...

Perimetric aspects of optic nerve aging.

Perimetry analyzes the efficiency of the entire visual system, but reveals the deterioration of even one of its components. Optic nerve changes, especially those of ischemic nature, which most frequently involve the middle and advanced age, cause typical perimetric findings. Manual kinetic perimetry is particularly indicated for the detection and definition of sectorial and global contractions. Manual static perimetry provides precise information on defect depth. Automated static perimetry quantifies the defect density in a large number of positions and also provides data on the significance of changes recorded during the follow-up. In normal subjects every type of perimetry shows a physiological decay of light sensitivity as a consequence of the aging of the visual system (about 2 dB per decade) and the reduced efficiency of the optic nerve is undoubtedly one of the components of this functional deterioration.

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.

[Problems of automated perimetry (author's transl)]. / Probleme der automatischen Perimetrie.

The choice of the most convenient computer, the strategies for stimulus presentation, the fixation control, the presentation of results and the response objectivation are the main problems of automated perimetry, some of which are already solved, others are likely to be solved in the near future. The authors present their experiences on automation of perimetry and indicate future perspectives of this procedure.

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

We 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 Best's macular dystrophy could be seen. Pathogenetic relationships between all of these dystrophies of the RPE can be supposed.

Preliminary results about a new remotely controlled projection campimeter.

A newly remotely controlled projection campimeter is described. The instrument can be remotely controlled either automatically by a minicomputer or manually by an operator. The introduction of the computer allows the elimination of the systematic errors due to the operator. Moreover, the campimeter is enabled to choose the optimal strategy for target presentations. The last task of the computer consists in the memorization of the graphical results, their comparison and their quantification.

The macular recovery test after photostress in normal and diabetic subjects.

The 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.