This report for the Belgian Ophthalmological Society concerns a number of fundus diseases, which most ophthalmologists only rarely encounter. Still it is of importance that they should be able to recognize them, not only because most of these eye diseases are treatable when they are diagnosed early enough, but also because they are sometimes associated with major visceral and neurological problems. The ophthalmologist may be the first practitioner to suspect a von Hippel-Lindau's disease or a neurofibromatosis. He should realize at that moment that his role is not only to treat the eyes but also to advise his patient, refer him to other specialists and consider the genetical implications of his diagnosis. Clinicopathologic correlations are of great importance and we felt that it was necessary to emphasize the histopathological aspect of these diseases. A report has to overview the literature on a specific topic. The literature on vascular tumors of the fundus is extremely vast and even if we tried to be as complete as possible, we must confess that we did not cite every author who published on such cases. A third aspect, which was considered as important, was to provide sufficient clinical and histopathologic examples of the various disease, which are reviewed. We are indebted to a large number of friends who kindly authorized the publication of their material. In particular we wish thank Prof. A. Brini (Strasbourg), Dr. D. de Wolff-Rouendaal (Leiden), Prof. P.

1. Choroidal Hemangioma.- I. Pathogenesis.- II. Clinical forms.- III. Symptoms.- IV. Complications.- IV. 1. Retinal complications.- V. Diagnosis.- VI. Histopathology.- VII. Treatment.- 2. Retinal Angiomatosis - von Hippel-Lindau's Disease.- I. Pathogenesis.- II. Incidence.- III. Heredity.- IV. Ocular findings.- V. Associated neurological and visceral involvement or von Hippel-Lindau's disease.- VI. Association of vHL disease with other diseases.- VI. 1. Association with other phakomatoses.- VII. Diagnosis.- VII. 1. Retinal angiomatosis.- VIII. Differential diagnosis.- IX. Pathology.- X. Treatment.- 3. Capillary Hemangioma of the Optic Disc.- I. Classification of angiomatous tumors of the optic disc.- II. Incidence.- III. Clinical features.- IV. Relationship with von Hippel-Lindau's disease.- V. Diagnosis.- VI. Differential diagnosis.- VII. Histopathology.- VIII. Treatment.- 4. Cavernous Hemangioma of the Retina and of the Optic Disc.- I. Incidence.- II. Clinical features.- III. Systemic manifestations - Gass' syndrome.- IV. Differential diagnosis.- V. Histopathology.- VI. Treatment.- 5. Congenital Arteriovenous Communications in the Retina.- I. Pathogenesis.- II. Heredity.- III. Incidence.- IV. Ocular manifestations.- V. Wyburn-Mason syndrome.- VI. Evolution of the retinal lesions.- VII. Histopathology.- VIII. Diagnosis.- IX. Differential diagnosis.- X. Treatment of the fundus lesions.- 6. Neurofibromatosis or von Recklinghausen's Disease.- I. Pathogenesis.- II. Incidence and heredity.- III. Pathognomonic lesions.- IV. Fundus examinations in von Recklinghausen'Es disease.- V. Other ophthalmological manifestations.- VI. Association with other phakomatoses.- VII. Treatment.- 7. TUBEROUS SCLEROSIS.- I. Incidence and heredity.- II. Diagnostic criteria.- III.Non-ocular manifestations of tuberous sclerosis.- III. 1. Cutaneous manifestations.- IV. Ocular manifestations of tuberous sclerosis.- V. Associations.- 8. Congenital Retinal Telangiectasis.- I. Pathogenesis.- II. Incidence.- III. Heredity.- IV. Clinical aspects.- V. Associated conditions.- VI. Differential diagnosis.- VII. Histopathology.- VIII. Treatment.- 9. Idiopathic Juxtafoveolar Retinal Telangiectasis.- I. Incidence.- II. Heredity.- III. Clinical aspects.- IV. Differential diagnosis.- V. Histopathology.- VI. Pathogenesis.- VII. Treatment.- 10. Coats' Syndrome and Retinitis Pigmentosa.- I. Incidence.- II. Clinical characteristics.- III. Differential diagnosis.- IV. Histopathology.- V. Pathogenesis.- VI. Treatment.- 11. Presumed Acquired Retinal Angiomatosis (Adult Coats' Disease).- I. Incidence.- II. Clinical aspects.- III. Differential diagnosis.- IV. Histopathology.- V. Pathogenesis.- VI. Treatment.- 12. Acquired Retinal Macroaneurysms.- I. Incidence.- II. Clinical manifestations.- III. Associated diseases.- IV. Histopathology.- V. Pathogenesis.- VI. Differential diagnosis.- VII. Treatment.