Crystalline lens

Augen-hornhaut,/. cornea, -kammerwasser, n. aqueous humor, -licht, n. eyesight, -lid, n. e3 elid. -linse, /. crystalline lens eye lens. e3 epiece. -marmor, m. eye-spotted marble, -mass, n. measure by eye. -merk, n. object in view, aim. -nerv, m. optic nerve, -nichts,... 

Seh-feld, n. field of vision, field of view, -lehre, /. optics, -hnse, /. (Anat.) crystalline lens. Sehne,/. sinew, tendon string, cord (Metal.)... 

Babizhayev, M.A. (1989a). Antioxidant activity of L-carnosine, a natural histidine containing dipeptide in crystalline lens. Biochim. Biophys. Acta 1004, 363-371. 

Terry, T.L. (1942). Extreme prematurity and fibroblastic overgrowth of persistent vascular sheath behind each crystalline lens. 1. Preliminary reports. Am J. Ophthalmol. 25, 203-243. 

Cataract—A clouding of the crystalline lens of the eye which obstructs the passage of light. 

After refraction of the light in the cornea and the crystalline lens, the light has to pass through the vitreous before it reaches the neural component of the retina. 

ABN. PIGMENT. OPTIC NERVES FAILURE OF THE CHOROID CRYSTALLINE LENS OUT ABN.PIGMENTAT10N gg INCOMP. SEPARATION CYCLOPIA IRREGULAR SHAPE MALPOSITIONED MICROPHTALMIA ABSENT... 

Miscoiling of gut (20), no swimming (20), opacity of crystalline lens (20), eyes with irregular shape (18), microphthalmia (1), eyes malpositioned (1), microencephaly 6), edema O (1), edema OC (1), edema OCA (1), edema AOFC (1), edema A (1), blister ventral (4), general hemorrhage (1), wavy tail (2)... 

Cataract. A loss of transparency of the crystalline lens of eye, or of its capsule. Cecolectomy. Excision of a segment or all of cecum. 

Davies, N.P., and Morland, A.B. Color matching in diabetes Optical density of the crystalline lens and macular pigments, Invest. Ophthalmol. Vis. Sci., 43, 281-289, 2002. 

A 59-year-old woman who for 20 years had taken chlorpromazine up to 1200 mg/day (mean dose 400 mg/day) gradually developed blurred vision in her left eye. Slit-lamp biomicroscopy showed multiple fine creamy-white deposits on her corneal endothelium and anterior crystalline lens capsule bilaterally. Microstructural analysis of the corneal endothelium showed that there were no abnormalities in cellular morphology resulting from these deposits. 

The lens grows with age, and colorations or opacities may develop and interfere with vision. Cataract formation may be enhanced by some miotics, steroids, and phenothi-azines. Aldose reductase inhibitors, which prevent the conversion of sugars to polyols, appear to prevent or delay diabetic cataract. Levels of glutathione and other compounds drop during the formation of some types of cataracts.The pharmacokinetics of delivery and penetration of such compounds into the crystalline lens is currently of great interest. 

In addition, most eyes with primary open-angle glaucoma treated with pilocarpine demonstrate narrowing of the anterior chamber angle and thickening of the crystalline lens after each instillation of the drug. 

Methylene blue can also be administered intracamerally to stain the crystalline lens capsule to aid in visualization during cataract surgery. 

Iris-supported intraocular lens Subluxated crystalline lens Subluxated intraocular lens... 

Ectopia lentis may occur as part of the syndrome of homocystinuria and Marfen s syndrome. Dilate these patients with caution with a weak mydriatic due to the risk of angle closure. Place the patient in a supine position during the fundus assessment.After the examination, confirm that the crystalline lens remains behind the iris and then mydriasis can be reversed by using a miotic, such as 0.5% dapiprazole. 

Glaucoma was described by Hippocrates as a known affliction of the eyes. The word glaucoma is derived from the Greek word glaukoma, which means opacity of the crystalline lens and probably referred to several conditions of the eye that were not differentiated from what we now know to be glaucoma. 

Many drugs have been associated with corneal and crystalline lens opacities, including phenothiazines, allo-purinol, phenytoin, diuretics, and heavy alcohol consmnp-tion. Over 16 drugs are listed to be associated with epithelial vortex keratopathy alone in a recent review, whereas the stroma is affected much less frequently. A variety of ocular toxicities are well recognized, aside from isolated case reports, and the drugs responsible for these side effects are listed in Table 35-2. 

Drugs That Can Affect the Cornea and Crystalline Lens... 

Figure 35-7 Mechanism of drug-induced myopia. (A) Image on retina in normal eye. (B) Drug-induced ciliary body edema causes relaxation of zonules, which in turn causes thickening of crystalline lens and myopic shift of refractive error.

Not only is amiodarone well-known to cause corneal toxicity (see Drugs Affecting the Cornea and Crystalline Lens, above), but it also can cause optic neuropathy. 

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