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G Coscas

Publications and source records attributed to G Coscas.

At least 19 recordsLinked to original sources
PubMed1999

Age-related macular degeneration in grandparents of patients with Stargardt disease: genetic study.

PURPOSE: To report clinical features and molecular genetic study in three unrelated families in which age-related macular degeneration was observed in grandparents of patients with Stargardt disease. METHODS: A complete ophthalmologic examination including best-corrected visual acuity measurement, fundus examination, and fluorescein angiography was performed on all members of the three families. The entire coding sequence of the ABCR gene was analyzed using a combination of single strand conformation polymorphism and direct sequence analysis of the 50 exons. RESULTS: Compound heterozygous missense mutations were observed in patients with Stargardt disease (Arg212Cys, Argl107Cys, Gly1977Ser, Arg2107His, and le2113Met). Heterozygous missense mutations were observed in the grandparents with age-related macular degeneration (Arg212Cys and Arg1107Cys). CONCLUSIONS: We report phenotype and genotype findings in three unrelated families segregating patients with Stargardt disease and age-related macular degeneration. The hypothesis that the Arg212Cys and Arg1107Cys ABCR gene mutations could be susceptibility factors for age-related macular degeneration is discussed. We speculate that the relatives of patients affected with Stargardt disease who are carriers of heterozygous ABCR gene mutations may have a higher risk of developing age-related macular degeneration.

ATP-Binding Cassette Transporters↗
PubMed1999

Radiotherapy for isolated occult subfoveal neovascularisation in age related macular degeneration: a pilot study.

BACKGROUND/AIMS: Teletherapy has been proposed as a possible treatment for choroidal neovascular membranes (CNV), secondary to age related macular degeneration (AMD) not amenable to laser photocoagulation. The aim of this prospective study has been to investigate the effect of teletherapy on isolated occult choroidal neovascular membranes of subfoveal location. METHODS: 28 AMD patients presenting with retrofoveal isolated occult CNV demonstrated by fluorescein angiography were treated by external beam radiation. A complete ophthalmological examination, fluorescein angiography, and indocyanine green angiography (ICG) were performed within 15 days before treatment and repeated at follow up. A total dose of 16 Gy was applied in four sessions of 4 Gy using a 4 MeV photon beam. Follow up ranged from 6 to 9 months (mean follow up 6.4 months). RESULTS: Visual acuity was found to be stable in 68% of the cases. The decrease in visual acuity was of 3-6 lines in 18% and of more than 6 lines in 10% of the eyes at last examination. On fluorescein angiography the size of the lesion area was found to be stable in 67%, decreased in 13%, and increased in 20% of the cases. On ICG angiography the size of the CNV was stable in 93% and increased in 7% of the cases. All the eyes experiencing a visual acuity decrease showed either no change or an increase in size of the membrane on fluorescein angiography and/or on ICG. CONCLUSION: According to this study with strict inclusion criteria, external beam radiotherapy seems to have a beneficial effect on the evolution of isolated occult subfoveal CNV.

Aged↗
PubMed1999

Natural history of macular subretinal hemorrhage in age-related macular degeneration.

PURPOSE: To define the natural course of extensive submacular hemorrhage in age-related macular degeneration (AMD). PATIENTS AND METHODS: The clinical charts of 54 patients (60 eyes) older than 55 years with subretinal hemorrhage larger than 1 disk diameter and extending beneath the fovea were retrospectively reviewed. The age of the patient, the use of antihypertensive or anticoagulant medication, visual acuity, biomicroscopic and fluorescein and indocyanine green (in 33 cases) angiographic data were recorded at presentation and during follow-up. RESULTS: At the initial examination, average visual acuity was 20/240 (range from 20/70 to light perception). During follow-up (mean 24 months) visual acuity worsened in 80% of the eyes with a mean final visual acuity of 20/1, 250 (range from 20/100 to light perception). The initial size and thickness of hemorrhage were correlated with initial and final visual acuity. Recurrence of hemorrhage resulted in an important impact on final visual acuity. Anatomic outcome showed fibrous tissue proliferation in 23 eyes (38.3%), atrophic scar in 15 eyes (25%) and occurrence of a retinal pigment epithelium tear in 13 eyes (21.6%). CONCLUSION: The visual outcome in eyes with submacular hemorrhages due to AMD is very poor. Size and thickness of the hemorrhage influenced negatively the natural prognosis. A surgical approach can be considered although it has not yet a widespread use.

Aged↗
PubMed1998

The epsilon4 allele of the apolipoprotein E gene as a potential protective factor for exudative age-related macular degeneration.

PURPOSE: Apolipoprotein E (ApoE) is a polymorphic protein that plays a central part in plasma metabolism of lipids and in central nervous system lipid homeostasis. Our purpose was to evaluate the potential role of ApoE polymorphism in the occurrence of exudative age-related macular degeneration associated with drusen, which contain lipids. METHODS: We analyzed apolipoprotein E genotypes in 116 unrelated patients with exudative age-related macular degeneration in one eye and hard drusen (n = 39) or soft drusen (n = 77) in the other eye, and compared the results with those of age-matched and sex-matched control subjects (n = 168). Apolipoprotein E alleles were detected by a ploymerase chain reaction-based method. RESULTS: A lower frequency of the epsilon4 allele carriers was observed in the exudative age-related macular degeneration group compared with control subjects (12.1% vs 28.6%, respectively; P < .0009). The epsilon4 allele was less frequent in the age-related macular degeneration group compared with control subjects (0.073 vs 0.149, respectively; P < .006). This decreased frequency of the epsilon4 allele was mainly observed in the soft drusen subgroup compared with control subjects (0.045 vs 0.149, respectively; P < .0009). CONCLUSION: This lower relative frequency of the epsilon4 allele supports the hypothesis that the ApoE gene is a genetic protective factor identified in age-related macular degeneration.

Aged↗
PubMed1998

Macular dystrophy, diabetes, and deafness associated with a large mitochondrial DNA deletion.

PURPOSE: To report the mitochondrial DNA in a 17-year-old patient with diabetes, deafness, cataract, and maculopathy. METHOD S: Ophthalmologic examination, fluorescein angiography, and electroretinogram were performed. Detection of deletion was analyzed by polymerase chain reaction and Southern blot, and screening for the A3243G mitochondrial DNA mutation was performed. RESULTS: A short fragment of approximately 8.5 kb corresponding to deleted mitochondrial DNA was detected. The A3243G mitochondrial DNA mutation was not found. CONCLUSIONS: A 7-kb heteroplasmic deletion of the mitochondrial genome was found in this patient. No mitochondrial DNA deletion has been reported previously in association with macular dystrophy.

Adolescent↗
PubMed1998

Exclusion of the apoE gene in autosomal dominant retinitis pigmentosa.

Our purpose was to search for mutations in the apolipoprotein E (apoE) gene and to evaluate the role of apoE polymorphisms in the occurrence of autosomal dominant retinitis pigmentosa (ADRP). The ApoE gene coding sequence was analyzed in 51 unrelated patients affected with ADRP. A screening for mutations by SSCP and an analysis of the apoE polymorphisms were performed using PCR and restriction enzymatic digestion. No abnormal patterns of migration were observed by SSCP analysis. No significant statistical difference was seen between our ADRP population and the French general population for apoE allele frequency. From these results we report that the apoE gene does not seems to be involved in our ADRP population.

Apolipoproteins E↗
PubMed1998

[Radiotherapy of occult neovascularization in senile macular degeneration: initial results of a pilot study].

BACKGROUND: AMD is the leading cause of legal blindness in people aged of more than 50 in industrialized countries. Occult neovascularization accounts for more than 70% of all exsudatives forms of AMD. Radiotherapy has been proposed as a possible treatment for retrofoveal neovascularization. We present the first results of a pilot study actually ongoing at the AMD Center in Creteil. PATIENTS AND METHODS: 44 patients (46 eyes) presenting occult choroidal neovascularization involving the fovea, aged of > 50 years and with a minimal visual acuity of at least 0.1 were included. They received a total dose of 16 Gy in 4 sessions of 4 Gy. All the patients were checked after 3 months. RESULTS: Visual acuity was globally maintained (> 0.1 in 93% of the eyes). Only one eye suffered a significant loss of vision (> 6 lines) and 11% suffered a moderate loss of vision (> 3 lines). Moreover 67% of eyes still had a near vision of 0.5 or more with reading glasses. On fluorescein angiography 17.5% of the eyes experienced an increase of the size of the occult neovascularization of > 0.5 Disk Area (DA), 76% showed no modification and 6.5% demonstrated a decrease in size of > 0.5 DA. CONCLUSIONS: As it has been shown that the antimitotic action of radiotherapy is most effective after 3 months, the present results suggest better evolution than natural history. However, as occult choroidal neovascularization is a slow-evolving disease further follow-up is needed to confirm it.

Aged↗
PubMed1998

[Indocyanine green angiography of basal laminar drusen in the retinal pigment epithelium associated with vitelliform macular degeneration].

PURPOSE: In the mid-late life, basal laminar drusen can be associated with vitelliform macular degeneration and choroidal neovascularization. The differential diagnosis between these two clinical entities is not always easy with fluorescein angiography. The aim of this case report is to describe the indocyanine green angiographic features of basal laminar drusen and pseudo-vitelliform material and to evaluate the role of ICG angiography in differentiating new choroidal vessels from vitelliform macular degeneration. PATIENTS AND METHODS: Six patients (12 eyes) with central visual loss and metamorphopsia underwent a biomicroscopic examination. Diagnosis was basal laminar drusen and bilateral vitelliform macular degeneration. Fluorescein and indocyanine green angiographies were performed and the results were compared. RESULTS: In all eyes, basal laminar drusen were hyperfluorescent with both angiographies. On fluorescein angiography, the macular material was hypofluorescent early, but gradual staining occurred from the borders in the late phase. In 8 out of the 12 eyes, fluorescein angiographic characteristics of the macular lesions could not provide clues to differential diagnostic between new choroidal vessels and vitelliform material. On indocyanine green angiography, in 8 eyes the material remained intensely hypofluorescent during the whole sequence. In 4 eyes, indocyanine green angiography allowed the identification of hyperfluorescent well-defined new choroidal vessels. CONCLUSIONS: Indocyanine green angiography allows the visualization of basal laminar drusen and can easily differentiate choroidal neovascularization from acquired vitelliform degeneration.

Angiography↗
PubMed1998

[Retinal vein occlusion and lipoprotein (a)].

PURPOSE: Epidemiological studies have shown a significant correlation between increased levels of lipoprotein (a) and coronary and cerebral vascular diseases. Lipoprotein (a) presents a striking homology with plasminogen and may therefore complete with binding of plasminogen at fibrin and at the endothelial cell surface, leading to fibrinolytic system dysfunction. The aim of this work is to study the relationship between increased levels of Lp(a) and retinal vein occlusion. METHODS: 132 consecutive patients with retinal vein occlusion were screened for lipoprotein (a) level. They also underwent initial and final visual acuity measurement, fluorescein angiography and blood tests including glucose, cholesterol and triglyceride levels, apolipoprotein A1 and B, protein electrophoresis, coagulation tests. Lipoprotein (a) results were compared with those of 52 age, sex and cardiovascular risk factors-matched controls. RESULTS: Lipoprotein (a) values were significantly higher in the retinal vein occlusion group than in the control group (p = 0.05). Elevated lipoprotein (a) (> 0.1 g/l) levels were observed more often in retinal vein occlusion patients (61%) than in the controls (42%; p < 0.02). No correlation was found in retinal vein occlusion patients between high levels of lipoprotein (a) and a severe form of retinal vein occlusion. Lipoprotein (a) levels were similar in central vein and branch vein occlusion patients. CONCLUSION: Lipoprotein (a) has been shown to be correlated with cardiovascular disorders and may also be involved in retinal vein occlusion, probably by dysfunction of the fibrinolytic system. However, it does not seem to be a prognostic factor of retinal vein occlusion and its role has to be elucidated in further studies.

Adolescent↗
PubMed1997

Indirect scatter laser photocoagulation to subfoveal choroidal neovascularization in age-related macular degeneration.

BACKGROUND: Occult choroidal neovascularization (CNV), poorly defined on fluorescein angiography, is present in the majority of patients with exudative complications of age-related macular degeneration. For patients who present with this type of subfoveal CNV but who have useful visual acuity, no form of treatment is of proven benefit. Accordingly, a pilot randomized trial of indirect laser treatment was performed. The rationale of this treatment was to inhibit the CNV through laser-induced effects on the retinal pigment epithelium. METHODS: Patients with occult subfoveal CNV without retinal pigment epithelial detachment and with visual acuity of 20/200 or better were randomized to treatment or control groups. A grid of laser burns was applied to the macula beyond the area of serous retinal detachment and of angiographically defined occult CNV. RESULTS: After an average follow-up of 38 months, there was no difference in mean final visual acuity (0.12 treated, 0.14 control) or clinical outcome between treated and untreated groups. Fluorescein angiography showed gradual enlargement in the occult CNV in 58% of eyes in both groups. A decrease in visual acuity to worse than 20/200 (54% of treated, 50% of control eyes) was associated with ingrowth of well-delineated CNV (6 treated, 7 control eyes) or progression to a fibroglial or atrophic scar (11 treated, 8 control eyes). CONCLUSIONS: No benefit was demonstrated for scatter photocoagulation of the macula in patients with age-related macular degeneration and occult subfoveal CNV with initially good visual acuity. There were, however, no complications related to treatment.

Aged↗
PubMed1997

Indocyanine green angiography of drusen.

PURPOSE: To analyze the indocyanine green angiographic findings of drusen in the early stages of age-related macular degeneration. METHODS: Sixty-nine eyes of 53 consecutive patients with drusen but without exudative complications of age-related macular degeneration were studied. Drusen were classified into four groups: hard drusen, drusen derived from clusters of hard drusen (hard cluster-derived drusen and soft cluster-derived drusen), membranous drusen, and regressing drusen. An additional category was constituted by reticular pseudodrusen that could be associated with drusen of either the inner or outer macula. Results of contact lens biomicroscopy and fluorescein angiography were compared with findings on indocyanine green angiography. RESULTS: Hard drusen, either isolated hard drusen or hard cluster-derived drusen, were hyperfluorescent during indocyanine green angiography; in contrast, all sizes of soft drusen derived from clusters of hard drusen were hypofluorescent throughout the angiogram. Membranous drusen, visible on biomicroscopy and fluorescein angiography, were not visible during indocyanine green angiography. Regressing drusen may have showed hyperfluorescence at the early stages of indocyanine green angiography, but associated calcium and pigmentation were hypofluorescent. Reticular pseudodrusen were visible on red-free photographs; on midphase and late-phase indocyanine green angiography using the scanning laser ophthalmoscope only, reticular pseudodrusen were seen as a pattern of hypofluorescent dots. CONCLUSION: The indocyanine green angiographic findings add to and support the clinicopathologic classification of drusen. Indocyanine green angiography may help to distinguish the different types of drusen and may thus be of use in evaluating the risk of progressive age-related macular degeneration in patients with drusen.

Adult↗
PubMed1996

[Age-related macular degeneration].

Age-related macular degeneration is the leading cause of non treatable blindness in industrialized countries. The impairment of visual acuity is preceded by the occurrence of "precursors" some of which are the witness of aging and others are the first symptoms of age-related degeneration of the macular retina. The disease involves both eyes with time resulting in a major handicap. Eventually, central visual acuity is destroyed, making reading, writing and recognition of faces impossible. Different clinical types are identified: the atrophic form for which there is at present no possibility of treatment, and the neovascular form in which the destruction of the new vessels with laser photocoagulation is beneficial. However, only an early diagnosis and treatment may allow a preservation of central vision. New possibilities of angiographic diagnosis, new therapeutic approaches (macular surgery or transplantation) based on physiopathogenic research, provide new hopes.

Age Factors↗