Amyloid of the Eye

AMYLOID OF THE EYE, a pathological process in which amyloid substance deposits in the tissues of the eye (see Amyloid degeneration). This process is of an exclusively local character. It affects, mainly, the conjunctiva in all its parts and the cartilage of the upper and lower eyelids; the cornea is rarely affected, and the amyloid degeneration of the latter has nothing in common with that of the conjunctiva. In the conjunctiva, the process of A. g. is clinically expressed in two forms: 1) in the form of an isolated, so-called primary amyloid tumor (a rare form), for example, in the area of the semilunar fold, and in the cartilage; and 2) in the form of diffuse degeneration, as well as in the size of the conjunctiva and cartilage of the eyelids (a more frequent form). Usually, the process of A. g. begins in the area of the transitional fold of the conjunctiva of the upper or lower eyelid. The transitional fold thickens, sometimes remaining smooth and even, and sometimes giving rise to uneven growths. The conjunctiva acquires here a special yellowish color with a grayish tint, resembling wax in appearance, tears easily, but bleeds little. The conjunctiva of the eyeball also thickens, becomes wax-like and ring-shaped; it rises around the cornea. Later, the cartilage of the eyelid, the semilunar fold, and the lacrimal caruncle become involved in the process. The cartilage increases and becomes hard to the touch. The skin of the eyelids remains unchanged, but the eyelid as a whole increases many times over (see Figure 1). Due to its weight, the upper eyelid droops down; the lower eyelid also thickens, loses its elasticity, and slightly lags behind the eyeball. The cornea sometimes becomes cloudy (pannus). Subjectively, patients complain of visual disturbances, difficulty in eye movements, a feeling of heaviness, and the disfigurement caused by the disease. The process of A. g. has a chronic course, lasting for many years; it sometimes affects both eyes, more often one. Women are affected slightly less often than men; the most frequent age of patients is from 25 to 35 years; cases of A. g. are known in children and the elderly. Amyloid of the conjunctiva of the eyelids is rare: from 1871 to the present time, only 133 such cases have been described in the literature; they were observed in Western Europe and America, but most often in our country. The diagnosis of local amyloid of the eyelids in clearly expressed cases presents no difficulty (see Figure 1); in the initial forms, A. g. can be confused with hyaline degeneration, with the diffuse form of trachoma, with syphilitic tarsitis; sometimes amyloid tumors were confused with malignant neoplasms. The diagnosis is established most accurately by histological examination. In microscopic examination of sections of amyloid-degenerated connective tissue or eyelid cartilage, different pictures are found in different stages of the process. Kubli (1881) distinguished four phases of amyloid degeneration: growth of adenoid tissue, hyaline degeneration, clearly expressed amyloid degeneration, and the stages of calcification and ossification. This division still has a certain significance, although it cannot always be strictly carried out in practice. In the early stages of the process, changes are found in the subconjunctival layer: here there is abundant infiltration (adenoid growths) of epithelioid cells with thin layers of connective tissue, in which amyloid granules deposit. In the future, the number of granules increases, depositing in larger foci, or the conjunctiva and cartilage undergo diffuse-amyloid degeneration. Giant cells are sometimes found on the periphery of amyloid-degenerated areas. Blood vessels are also involved in amyloid degeneration (see Figure 2). In far-advanced cases, the eyelid muscles also undergo amyloid degeneration; calcification and the formation of bony lamellae are observed in the amyloid-degenerated tissues. There are known cases of amyloid of the eyelids without the presence of trachoma in the patient, the previous existence of which was at one time considered obligatory. The prognosis in local amyloid of the eyelids is not entirely favorable; left to itself, the process slowly but inevitably leads to the aforementioned disturbances and to the impossibility of using the eye. The best results are given by surgical intervention. Depending on the extent of the process, partial or complete excision of the affected tissue is performed, covering the wound with healthy conjunctiva, and it is watched to ensure that secondary changes do not occur in the postoperative period. In far-advanced cases, they are limited to partial cutting or curettage with a sharp spoon. It happens that after this the course of the process is delayed and even regression is observed. Amyloid of the cornea is observed on old scars (leukomas, staphylomas, corneo-scleral scars). In this scar tissue, amyloid deposits in the form of grains and droplets. Clinically, this is manifested by a yellow color of the degenerated areas.

Figure 1. Amyloid of the lower eyelid.

Figure 2. Homogeneous masses of amyloid around blood vessels and in interstitial connective tissue.

In far-advanced cases, they are limited to partial cutting or curettage with a sharp spoon. It happens that after this the course of the process is delayed and even regression is observed. Amyloid of the cornea is observed on old scars (leukomas, staphylomas, corneo-scleral scars). In this scar tissue, amyloid deposits in the form of grains and droplets. Clinically, this is manifested by a yellow color of the degenerated areas.