OPACITY OF THE CORNEA. NEBULA. MACULA. 



LEUCOMA. 



Nebula, macula, leucoma, pigment spots, infiltration, cicatrix, vascular 

 or not, result of lead, silver or cocaine. Treatment : silver nitrate solution 

 in young and vigorous ; calomel : iodoform : avoid mercury and iodine at 

 the same time. Tatooing. 



As a sequel of inflammation of the cornea, persistent opacities 

 are very common occurrences. These may last only a short time 

 after the subsidence of the inflammation, or they may be per- 

 sistent and chronic. They are of all degrees of severity from a 

 mere bluish haze to a dense white cloud, or a dark pigment spot. 



The term nebula is given to the slightest form which appears 

 as a grayish blue but still transparent blue and may be so slight 

 as to pass without recognition except under focal or oblique il- 

 lumination. It shades off gradually into the adjacent healthy 

 cornea, and is often seen as a marginal zone when the centre of 

 the cornea is clear. 



Macula is more marked, requiring no special illumination to 

 detect it, especially when the dark pupil forms a background for 

 the affected area. It is not, however, of a clear white, but of a 

 grayish blue tint. 



Leucoma is a dense white spot or patch which reflects all the 

 light falling upon it, and has usually a sharply circumscribed 

 margin. 



Pigment spots are usually on the membrane of Descemet and 

 are the result of a previous adhesion of the iris and detachment 

 of a portion of its pigment. 



The white opacity may be merely a remnant of inflammatory 

 infiltration or it may be a fibrous cicatrix with or without a re- 

 maining minute ulcer. It may be the result of an insoluble de- 

 posit of lead or silver in the tissues. Sometimes it will form as 

 the result of the application of cocaine. 



Treatment. A case of slight inflammatory infiltration can 

 usually be cleared up by touching it daily with a solution of 2 

 grs. silver nitrate in an ounce of distilled water. This is es- 

 pecially satisfactory in the young and healthy, in which the 

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