Arteriovenous malformation in the retina of a monkey

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND): Non-proliferative and Proliferative Lesions of the Non-human Primate (M. fascicularis)

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions Project (www.toxpath.org/inhand.asp) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in most tissues and organs from the nonhuman primate used in nonclinical safety studies. Some of the lesions are illustrated by color photomicrographs. The standardized nomenclature presented in this document is also available electronically on the internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions as well as lesions induced by exposure to test materials. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature for lesions in laboratory animals will provide a common language among regulatory and scientific research organizations in different countries and increase and enrich international exchanges of information among toxicologists and pathologists.

The congenital unilateral retinocephalic vascular malformation syndrome (bonnet-dechaume-blanc syndrome or wyburn-mason syndrome): review of the literature

Retinal arteriovenous malformations represent a rare syndrome in which a direct connection of major vessels without interposition of capillaries may lead to various complications such as thrombosis and vessel occlusion. This review comprises the computer-stored data of all the 121 patients with arteriovenous malformations described in the literature. Twenty-seven patients had typical Bonnet-Dechaume-Blanc syndrome (in this article designated as congenital retinocephalofacial vascular malformation syndrome), 25 had incomplete congenital retinocephalofacial vascular malformation syndrome (without facial skin lesions), 57 had isolated retinal arteriovenous malformations, and 12 had arteriovenous communications of the retina and distinct neurological signs, but without neuroradiological evidence of cerebral arteriovenous malformations (presumed cerebral arteriovenous malformations). Concerning the retinal findings, we found a distinct difference by comparing patients with congenital retinocephalofacial vascular malformation syndrome and those with isolated retinopathy without cerebral or facial malformations: extensive retinal malformations of vessels of most parts of the fundus occurred conspicuously more often in patients with retinal and cerebral arteriovenous malformations. In contrast, local retinal arteriovenous malformations occurred in all patients with isolated retinopathy without cerebral or facial malformations and rarely in patients with congenital retinocephalofacial vascular malformation syndrome. In conclusion, patients with arteriovenous communications of the retina should be examined early with brain and orbital neuroimaging to rule out cerebral arteriovenous malformations. Current therapeutic strategies include endovascular, surgical, and radiation procedures.

Functional and anatomical investigations in racemose haemangioma

PURPOSE

To determine the vascular morphology of racemose haemangioma and related functional alterations in arteriovenous (AV) malformation type 3.

METHODS

A 17-year-old patient with unilateral racemose haemangioma received a full ophthalmic examination including Snellen visual acuity (VA) and Goldmann visual field. The central vision was investigated by scanning laser ophthalmoscope (SLO) and multifocal electroretinogram (mfERG). The ocular haemodynamics were examined by fluorescence angiography and Doppler ultrasound. The tomographic contour of the vascular architecture was visualized using B-scan ultrasound, Stratus optical coherence tomography (OCT) and three-dimensional Heidelberg retina tomograph (3D-HRT II).

RESULTS

The VA of the patient's right eye was reduced to 20/400 and her visual field was constricted concentrically. Microperimetry revealed a small central field with good central fixation. The mfERG demonstrated reduced amplitudes of the central retina. On fluorescein angiography, there was a fast filling of the retinal branches related to the racemose vessels. Doppler ultrasound confirmed a significantly changed haemodynamic flow in the racemose vessels. Ultrasound, OCT and HRT demonstrated a prominent optic nerve head.

CONCLUSION

The racemose haemangioma led to a marked visual field defect. Racemose haemangiomas are associated with severe changes in the haemodynamics of the retinal vasculature.

Angiomatous malformation of the retrolaminar optic nerve

A vascular abnormality of the optic nerve was found incidentally in two infants whose eyes were enucleated because of the clinical suspicion of retinoblastoma. The lesion consisted of numerous thin-walled vascular channels within pial septa of the retrolaminar optic nerve. Although it is unclear if this angiomatous malformation could disturb vision, the lesion may be more common than can be inferred from the small number of reported cases.