Международный Ветеринарный Конгресс по Офтальмологии
Конгресс пройдет с 14 по 16 июня 2019 года в Конгресс центре отеля Гамма-Дельта (3 этаж)
Maldevelopment: report of two cases in the dog
Regnier A.1, Raymond-Letron I.2
1Department of Clinical Sciences and 2Department of Biological Sciences, National Veterinary School, 23 chemin des Capelles, B.P. 87614, Toulouse Cedex 3, France
Purpose: Ocular maldevelopment resulting in neural cyst formation can occur in chilhood, and include congenital cystic eye and colobomatous cyst (microphthalmos with cyst). Partial or complete failure in invagination of the primary optic vesicle results in cystic eye, while failure of fetal fissure closure results in the spectrum of ocular colobomas, a subset of which is colobomatous cyst. We report the cases of two young dogs that presented with an orbital cyst closely resembling human cysts of neural tissue.
Medical history: A three-month-old, male cocker spaniel (case # 1) and a female miniature poodle culled from a charity kennel and approximately aged six months (case # 2) were presented for evaluation of clinical signs related to abnormal aspect of one eye. On physical examination, the dogs were healthy and alert, and abnormalities were limited to the right eye. In both cases, no eyeball or any other ocular structures were identified on the right side and were replaced by an intraorbital mass distending the eyelids and covered with a pink vascularised membrane protruding through the palpebral fissure. Each mass was fluctuant on palpation, and ultrasonographically appeared as an anechoic cystic structure markedly larger in size than the healthy fellow eye. Surgical excision was performed, and in each case a multilobular cystic mass containing clear yellow fluid, was found to fill the whole orbital cavity. The specimens were processed for histopathological examination.
Pathology: Both cysts were lined by a thin wall composed of a neuroepithelial inner lining and a fibrous tissue outer wall with attached extraocular muscles. In case # 1, the neuroglial tissue layer contained areas of dysplastic inverted, multi-layered retina with rosettes and evidence of photoreceptor differentiation. An immature lens was present in the cystic cavity. In case # 2, serial sections disclosed the presence of a small pseudocystic pigmented mass lined by a collagenous connective tissue resembling sclera, and attached to inner trabeculations of the cyst wall. This mass contained malformed retina, uveal tract and lens, and presented posteriorly a large scleral coloboma opening into the cystic cavity.
Conclusion: The ocular cysts observed in these two dogs were clinically similar but histologically different. Case # 1 fullfilled the histological criteria of congenital cystic eye1, whereas pathological evaluation of case # 2 was consistent with colobomatous cyst with extreme microphthalmia2. These congenital malformations result from an arrest in the very early stages of ocular morphogenesis, and to the authors knowledge have never been reported in the dog.
A retrospective study evaluating the functional prognosis of surgical treatment for long standing anterior lens luxation in dogs
Ophtalmologie Veterinaire 64 Blvd Barry, 13013 Marseille, France
Purpose: Primary anterior lens luxation, in dogs, is regarded as an ocular emergency. The urgent surgical procedure based on lens removal combined , if necessary , to an anterior vitrectomy, is considered as a successful means to avoid glaucoma. This study was undertaken to evaluate the functional prognosis for the patients not submitted to a prompt therapy.
Methods: This study includes dogs surgically treated for anterior lens luxation one month or over after intial presentation. The initial diagnosis was made by the referring practitioner and confirmed at presurgical examination. Before surgery, the dogs were examined by slit lamp biomicroscopy, gonioscopy, applanation tonometry (TonoPen) and ERG. All cases identified or suspected for primary glaucoma were discarded. A total of twenty four dogs ( any breed, sixteen males, eight females, age range from five to fifteen years) are included in this evaluation. Twenty seven eyes were submitted to surgery. The time between the first examination and surgery ranges from one to eight months.
Results: The mean intra ocular pressure is 28 mmHg ( range 18-35mm). From the twenty seven electroretinograms, nineteen are considered as good and eight as bad responses (weak or no response). Satisfying postsurgical functional results were obtained from fifteen eyes.
Conclusion: The results of this study suggest that duration of lens luxation alone, cannot be used as basis for prognosis. Considering anterior lens luxation as an emergency, if adequate principle, has not to be taken as a dogma. In spite of very long duration, many cases remain good indications for surgery.