Weber U, Goerz G, Baseler H, Michaelis L
Augenklinik, Akadem. Lehrkrankenhauses Braunschweig.
Klin Monbl Augenheilkd. 1992 Sep;201(3):174-7. doi: 10.1055/s-2008-1045888.
After long-term treatment with high dosages, canthaxanthin causes a characteristic retinopathy with circular, macula surrounding crystals. As changes in retinal functionning disappear relatively easily after withdrawal of the drug, the crystals dissolve rather slowly--over about several years. Five patients showing a profound crystalline retinopathy were re-examined with an average of 69.7 months after withdrawal of the canthaxanthin-containing drug. Three of the patients were treated for erythropoetic protoporphyria (EPP) with Phenoro (2/5 beta-carotene, 3/5 canthaxanthin), two sisters took a canthaxanthin-containing formulation (1/8 beta-carotene, 7/8 canthaxanthin) for cosmetic reasons. Two female patients complained about an increased glare sensitivity, which was explainable for one of them with a subcapsular cataract. The retinal crystals decreased quite differently. Minor deffects of the retinal pigment epithelium remained unchanged in two patients. They increased slightly in the female patient with the smallest crystal formation but highest plasma cholesterol. Shortly after withdrawal of the drugs usually an increase of a-wave amplituded of the electroretinograms was found. The a-waves returned to normal and the b-wave amplitudes showed an increase up to the final control paralleling the reduction of the retinal crystals. A- and b-wave peak latencies which were prolonged under treatment returned to normal.
长期高剂量服用角黄素会导致一种特征性视网膜病变，出现环绕黄斑的圆形晶体。由于停药后视网膜功能的改变相对容易消失，而晶体溶解相当缓慢，大约需要数年时间。对5例患有严重晶体性视网膜病变的患者在停用含角黄素药物后平均69.7个月进行了复查。其中3例患者因红细胞生成性原卟啉症（EPP）接受了酚诺罗（2/5为β-胡萝卜素，3/5为角黄素）治疗，两姐妹出于美容原因服用了一种含角黄素的制剂（1/8为β-胡萝卜素，7/8为角黄素）。两名女性患者抱怨眩光敏感度增加，其中一名患者的这种情况可由晶状体后囊下白内障解释。视网膜晶体减少情况差异很大。两名患者视网膜色素上皮的轻微缺陷保持不变。在晶体形成最小但血浆胆固醇最高的女性患者中，这些缺陷略有增加。通常在停药后不久，视网膜电图的a波振幅会增加。a波恢复正常，b波振幅在最终检查时增加，与视网膜晶体的减少情况平行。治疗期间延长的a波和b波峰潜伏期恢复正常。
