Tumors ocular

Classe JG. Optometrist s duty to detect ocular tumors. South J Optom 1985 3 26-32. 

Semes L, Gold A. Chnical and legal considerations in the diagnosis and management of ocular tumors. J Am Optom Assoc 1987 58 134-139. 

It is known that ACAID contributes to ocular tumor survival and long-term survival of orthoptic corneal allografts. Some experiments showed that removal of NKT cells prevented the continued acceptance of ocular tumors and caused the elimination of the immune privilege of the eye. Without functioning NKT cells, mice were not able to accept orthoptic corneal allografts for prolonged periods of time (Sonoda et al., 2002). This data demonstrates the essential role of NKT cells in the generation of ACAID. New information about ACAID may lead to application of ACAID mechanisms in prevention and treatment of immune-media ted inflammatory diseases in humans. 

Several lipoprotein formulations have been tested for delivery of photosensitizers to tumor tissue [54-56] and it has been shown that LDL is a particularly suitable delivery vehicle for different porphyrins. Uptake of LDL complex is mainly mediated via an active endocytotic pathway, involving LDL receptors on both tumor cells and endothelial cells [57-60]. Depending on the time after administration, the LDL complexed photosensitizers can be found either in the vasculature [61], or in the tumor cells themselves [57,62]. Covalent linkage of LDL to chlorin e6 resulted in conjugates which were specifically taken up by LDL-receptor carrying fibroblasts, and a retinoblastoma cell line, indicating its potential use in ocular tumors [54]. 

BPD-MA is an example of a porphyrin, which in pre-clinical studies was shown to target the tumor vasculature. Intra-ocular tumors implanted in rabbit eyes were used as a model for neovasculature and the very efficient destruction of these tumors could be attributed primarily to the destruction of the tumor vasculature. The established choroidal vessels remained largely intact [61,161]. Based on these studies, this compound has been developed by QLT Phototherapeutics and Ciba-Vision as a first line treatment for age-related macular degenerateion (AMD) of the eye [162-166]. In 1999, approval for PDT using BPD-MA in the treatment of AMD was obtained in Switzerland and more recently in Canada, the USA and several other European countries. It is anticipated that the development of this agent or its analogues for oncological indications will be resumed. 

Retinoblastoma represents the most common malignant intra ocular tumor in children under the age of 5 years, with up to 90% of intra-ocular malignancies. 

It derives from neuroectodermal cells of the retina and presents clinically with strabism, leukocoria, and, perhaps, pain. While primarily being diagnosed by visual means, retinoblastoma may present with characteristic calcifications within an intraocular mass at CT. MRI allows to determine intra- and extra-ocular tumor extension and the presence of bilateral or trilateral (including pinealoma) tumor or intra-cranial metastasis. Differential diagnosis includes persistent hyperplastic primary vitreous body and Coats disease (MuELLER-FoRELL and PiTZ 2004). 

PDT is now established as part of the ophthalmologist s armamentarium for the treatment of abnormal vascular conditions in the eye. The therapy is proven to be safe and efficacious. In addition to the diseases mentioned above, there are a number of other ocular conditions in which PDT could play a role. These include diabetic macular edema, diabetic retinopathy, corneal neovasculature, and ocular tumors. While there are alternative therapies for these conditions, unlike AMD where there was no treatment, it is possible that PDT may offer some advantages over existing therapies. 

Antagonists of integrin av 33 inhibit the growth of new blood vessels into tumors cultured on the chick chorioallantoic membrane without affecting adjacent blood vessels, and also induce tumor regression [7]. Antagonists of av 33 also inhibit angiogenesis in various ocular models of retinal neovascularization [7]. 

Component of liposomes Protective coating for liposomes Protein stabilizer DNA transfection agent Surfactant in intranasal or ocular delivery Increasing susceptibility of tumor cells to cytotoxic drugs Liver gene delivery... 

Dorrell, M., Aguilar, E., Scheppke, L., Barnett, F., Friedlander, M. (2007b). Combination angiostatic therapy completely inhibits ocular and tumor angiogenesis. Proc. Natl Acad. Sci. USA 104 967-72. 

Before directly treating dry eye, any comorbid conditions should be treated to the best extent possible. As previously mentioned, any associated ocular disease, such as blepharitis, MGD, ocular allergy, infections, and contact lens-related problems, should be appropriately addressed. Local or systemic disease, such as thyroid orbitopathy and orbital inflammatory pseudotumor, can cause exophthalmos and proptosis and should be comanaged with the patient s primary care physician or appropriate specialist. Neuroimaging is often required to exclude orbital tumors in these cases. 

There is considerable discussion about whether ocular inflammation is paradoxically a potential adverse event of etanercept in either previously inflamed or previously uninflamed eyes. It is as yet imclear whether etanercept may induce new-onset uveitis or may prevent uveitis, although flares of uveitis have recently been shown to occur less than half as often in tumor necrosis factor-a-treated patients as placebo-treated control subjects. However, it seems clear that, because of a different mechanism of action, infliximab is more effective at treating certain types of ocular inflammation. 

A 2.7% ocular complication rate in 112 patients treated with a cumulative dose of carmustine 370 mg/m for intracranial tumors has been recorded (9). 

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