The Clinical And Pathologic Mechanism Study Of Orbital Cavernous Hemangioma

Objective To probe the pathogenesis of orbital cavernous hemangioma (OCH) on the basis of its pathologic structure and clinical character. (1) To study the clinical character of OCH and suppose the presence of pathologic mechanism, (2) To study the pathologic structure of OCH. ㏕o observe the pathologic structure of OCH and study the distribution and phenotype of endothelial cell (EC) and smooth muscle cell (SMC) in it. ㏕o investigate the expression of the structure protein and vascular growth factor in OCH to probe the pathogenesis of the abnormal sinusoid wall in it. (3) To investigate the ultra structure of OCH.Method (1) Fifty-two cases of OCH were analyzed retrospectively according to the clinical data, (2) Twenty-five specimens of OCH, 25 specimens of cavernous venous malformation (CVM) and 12 specimens of normal small vein were included in our study. (1) H-E stain was used to observe the pathologic structure of OCH, particularly the distribution of EC and SMC, and the numbers of EC and SMC in the vessel walls of both OCH and normal small veins were calculated. (2) Twenty-five specimens of OCH, 25 specimens of CVM and 12 specimens of normal small vein were selected for immunohistochemical stain with EnVision method. A. Monoclonal antibodies such as anti CD31 and SMA, which are the markers of EC and SMC were used to observe the phenotypes of these two kinds of cells. B. Monoclonal antibodies such as anti Fibronectin and Laminin were used to investigate the expression of structure protein. C. Monoclonal antibodies such as anti VEGF, TGF were used to investigate the expression ofvascular growth factor. (3) Ten specimens of OCH were selected for electron microscope observation of the ultra structures of OCH.Result (1) The main clinical findings of OCH are gradual exophthalmos, possible visual decrease, diplopia and ocular movement restriction. The images of B ultrasound could diagnose this disease. Computerized tomography(CT) and magnetic resonance imaging(MRI) are methods to diagnose and pinpoint OCH. The primary treatment of OCH is surgical removal. (2)Immunohistochemical analysis: The ratio of radius and thickness of OCH is much higher than CVM and normal small veins. The sinusoid wall does not increase its thickness consistent with the expanding of lumen of sinusoid. The ratio of ECs to SMCs in OCH and CVM is much less than in small veins; the expression of a -SMA in OCH is much less than in small veins, and the organization is more confused; the expression of CD31 in them is similar. The expression of Fibronectin and Laminin in OCH is much less than in small veins, but the distribution is similar. The expression of VEGF in both OCH and small veins are weaker than CVM. There is no difference in the expression of TGF.Conclusion OCH could be diagnosed by it ' s typical clinical manifestations. The prognosis of OCH is good. Surgical operation has no influence on visual acuity and intracranial structures. Hint about this characteristic: the nutrient vessel of OCH does not come from the ophthalmic artery, ophthalmic vein or intracranial vessel. Immunohistochemistry:(1) The EC and SMC in sinusoid wall develop disproportionally and the SMCs has an abnormal phenotype, which is the major pathologic basis of OCH. (2) The low expression of Fibronectin and Laminin plays an important role in the pathogenesis of the abnormal sinusoid wall in OCH. (3) There is disturbance of vascular remodelling in the development of sinusoid wall in OCH. Limited cases of OCH occur rhexis hemorrhage, which induces sudden exophthalmos. This finding is closelyrelated with the development deformity of vessel wall. The transition part between the normal nutrient vessels and the abnormal vessel could be deduced to be in an unstable and active stage which is responsible for the rhexis hemorrhage. OCH which sticks to the orbital apex could just be removed the main part to prevent the visual acuity from being destroied. Postoperatively, the residual tissue would be autoatrophy and bandage compression can prevent bleeding. These pheno...