No abstract

A review of reports on metastatic orbital tumors published from 1903 to 1998 in Japan revealed 128 patients, 74 males, 52 females and 2 whose sex was not recorded. The average age was 44.8 years, but varied depending on the primary tumor. Since 1980, metastatic orbital tumors have increased in Japan, especially those from the lung, liver and adrenal gland, while metastasis from the stomach has decreased slightly. Metastasis from the breast is still common. Most metastatic orbital tumors were from the lung, followed, in order, by breast, liver, adrenal gland and stomach. Males had four times as many metastatic orbital tumors from lung cancer than did females; only females had metastases from breast cancer; almost 90% of metastases from hepatoma were in males; metastasis from renal carcinoma was 2-3 times more common in males than in females. Metastasis from the liver and stomach is seen more frequently in Japan than in the United States and Europe. Ocular signs due to orbital metastases from hepatoma, neuroblastoma and gastric cancer were apt to appear earlier than the signs of the primary lesion. Metastases to the orbit were frequently bilateral in patients with neuroblastoma and malignant lymphoma. Specific ocular signs such as ecchymosis and conjunctival hemorrhages were seen in orbital metastasis from neuroblastoma and seminoma, while ocular pain was characteristic of malignant lymphoma. Orbital metastasis was very rare in patients with carcinoma of the uterus, ovaries, bladder, pancreas, colon or rectum in both Japan, the United States and Europe.

The strong immunoreactivity and the release of b-FGF in cultured fibroblasts of recurrent pterygia suggest that fibroblasts may play an important role in the recurrence of pterygium.

44 patients with atopic dermatitis who had had active generalized skin lesions, especially of the face, following transient remission after eczema in infancy were examined ophthalmologically. Their ocular findings have been correlated with the clinical features of atopic dermatitis. 25% of the patients with this clinical course had cataracts. However, the clinical features of the patients without cataracts were almost the same as those of the patients with. Thus, cataracts in patients with atopic dermatitis may not be due to the clinical symptoms and course but to other factors such as genetic, as in the case of asthma. Lenticular opacities were present in the posterior subcapsule in 50%, in the anterior subcapsule in 25% and throughout the lens in 12.5%. 2 patients with total lens opacities had shown rapid progression at the time of exacerbation of the skin lesions. Chronic conjunctivitis was found in 31.8%, superficial keratitis in 6.8% and retinal detachment in 2%.

This study presents the details of the microvasculature of the rat choroid visualized by scanning electron microscopy of vascular corrosion casts. Wistar Kyoto rats were anesthetized with intraperitoneal sodium pentobarbital. The vascular system was perfused with heparinized saline, and Mercox resin was injected into the cannulated carotid arteries. After polymerization of the resin, the vascular casts were macerated with potassium hydroxide, washed with water, and freeze dried. The casts were examined with a Hitachi S-2360N scanning electron microscope (SEM). Corrosion casts of the entire choroidal vasculature revealed that the two long posterior ciliary arteries supplied the entire uveal vasculature. In the posterior choroid, these arteries formed five to seven branches on each side supplying the adjacent choriocapillaris. No interarterial or arteriovenous anastomoses were seen. The choriocapillaris appeared as a nonhomogeneous and nonlobular monolayer capillary network, consisting of dense honeycomb and irregular patterns. There are two distinct venous systems in the rat choroid. The venous blood from the central region, peripapillary choroid, and sometimes the optic nerve head drain into the posterior ciliary vein. The venous blood from the iris, ciliary body, anterior choroid, and half of the posterior choroid drain into the vortex veins. Corrosion casts and the SEM have shown details of the choroidal vascular architecture. These three-dimensional observations indicate that the rat choroidal vasculature has different features from those of humans and other primates. Despite these interspecies differences, the establishment of a thorough baseline concept of choroidal vasculature should permit additional studies of the choroidal pathology and enable the proper interpretation of results from rat experimental models for extrapolation to humans. Anat Rec 264: [63][64][65][66][67][68][69][70][71] 2001.

No abstract

The changes in the capillary network of the retina in spontaneously hypertensive rats (SHR) were demonstrated by scanning and transmission electron microscopy. Corrosion casts with scanning electron microscopy provided a three-dimensional view of the microvasculature of the rat retina and could detect the conspicuous features of the retinal vasculature in SHR. In general, when hypertension lasted for 6–7 months in SHR, tortuosity of the retinal vessels was noted, and later the SHR retina showed increased tortuosity and generalized narrowing of the vessels, localized constriction of the veins, arteriovenous crossing defects, and marked capillary changes, such as caliber irregularity, narrowing, bead-like capillaries, loop formation and localized obliteration. At a later stage, when the blood pressure had been sustained for a long time, there was marked capillary constriction which first affected the superficial capillary network, then scattered capillary network constriction and finally capillary dropout. Transmission electron microscopy revealed narrow capillary lumina and thin endothelium with scarce cytoplasmic components and damaged pericytes. These morphological changes in the capillary network were probably due to structural damage to the endothelial cells, facilitated possibly by compression of the precapillary arterioles. The severity of these changes was usually proportional to the degree and duration of hypertension. These findings indicate that the retinal capillary changes are probably related to hypertension.

Plastic corrosion casts of the rat retinal vasculature were studied by scanning electron microscopy. This technique demonstrated the entire retinal vasculature of the rat. The retinal blood vessels supplying the rat’s retina have a definite and fairly constant pattern. At the disk there are usually six main artery and vein branches that run symmetrically towards the periphery. Veins are wider and more tortuous. The characteristic arrangement of endothelial cell nuclear indentations clearly differentiates arteries from veins. Retinal arteries have side-arm and dichotomous branchings. The number of vessel branches is greater on the nasal side than on the temporal side of the retina. The vein-over-artery crossing phenomenon is more frequent than the artery-over-vein. Retinal capillaries appear tortuous and are arranged cylindrically in two layers. The superficial network of capillaries comes essentially from arterioles, while deep layer capillary networks are more regularly and densely arranged and are mainly connected with venules. The inner and the outer capillary networks have interconnections, vertical runs and short vascular bridges. Within the retina there are regional variations in capillary pattern and distribution. More regular, dense and rich capillary networks are observed in the peripheral area than at the posterior pole area. No arteriovenous shunts were seen. The study of such plastic casts makes possible a more accurate assessment of some aspects of vascular abnormalities. These findings will be helpful in further investigations of retinal vascular abnormalities.