Intraimage reproducibility of measurements in the macular area using a computerized system.

An accurate analysis of the morphological changes which take place during pathological processes of the posterior pole is important for a correct diagnosis and therapeutic approach. The purpose of the study was to determine the intraobserver and interobserver reproducibility of the Image-net system 100 (Topcon, Japan) to take measurements on the retina. The program 'Linear/Areal Measurement functions' of Image-net system 100 which is an image digitalization technique, was tested. Twelve patients were consecutively selected from the patients of the Retina Center of the Department of Ophthalmology, University of Genoa. Three images of each eye were taken from each subject and only the best image was used in this study. The intraobserver and interobserver reproducibility of both the distance between two pre-set points (linear measurement), and the perimeter and area of preselected retinal zones were calculated. The repeatability (or intraobserver reproducibility) of the linear sizes was measured by the coefficient of variation and ranged from 0.32% to 7.38%, while the interobserver reproducibility ranged from 0.46% to 5.22%. The repeatability and reproducibility of the perimeters ranged from 0.72% to 9.63% and from 0.6% to 5.7%, respectively, while the repeatability and reproducibility of the areas ranged from 0.72% to 9.63% and from 0.6% to 5.7%, respectively. Although the results were quite good, the quality of the image of the fundus and the number of observers influenced the coefficient of variation; furthermore, the anatomy of the areas to be measured and the computer 'mouse' could increase the value of the coefficient of variation.

[Surgical treatment of primary and secondary cataract in severe myopia]. / Traitement chirurgical de la cataracte primaire et secondaire dans la myopie de degré élevé.

Secondary cataract after extracapsular surgery is one of the main complications in aphakic eyes. In severely myopic eyes secondary cataract not only impairs visual acuity but also interferes with peripheral retinal exploration; in these eyes Nd-Yag laser capsulotomies are not recommended because of the high risk of retinal detachment and also because this technique does not solve problems related to peripheral retinal examination. For these reasons, in severely myopic eyes the authors perform extra capsular cataract extraction without IOL implantation and, if secondary cataract appears, they perform surgical cleaning of the capsule. The authors emphasise the good visualization of the peripheral retina obtained with this technique.

[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.

[Changes in the internal limiting retinal membrane after epiretinal peeling]. / Altérations de la lame limitante interne de la rétine après pelage des membranes épirétiniennes.

The authors describe the histological features of an extensive epiretinal membrane surgically removed from an eye with posterior penetrating ocular trauma. A pars plana vitrectomy and removal of the epiretinal membrane were performed. Histological preparations revealed a large segment of internal limiting membrane (ILM) adherent to the epiretinal membrane. This case report illustrates two points: the adherence between ILM and Muller cells is quite weak; removal of extensive portions of ILM could encourage rapid re-proliferative phenomena.

A new therapeutical approach to central serous retinopathy, a hypothesis.

The authors report two cases of patients affected by Central Serous Retinopathy (C.S.R.) lasting few days; they were immediately started with an antiviral therapy (Acycloguanosine) for few days and in both cases the regression of symptoms and a flat retina were observed after a very shorter time than the spontaneous course. A fluorescein angiography confirmed a healing of the leaking points very few days after the therapy was discontinued. The authors discuss their finding in relation to the latest hypothesis on C.S.R. pathogenesis.

[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.