"60 CLINICAL DLVGNOSTICS. 



J^cnous en^or(!;eincnt does not come from plethora. It 

 may he ramiform, diffuse or punctiform, and varies in color 

 from a brick red to dark red or muddy (cyanotic). 



Raiiiifonn coui^cstion from disease occurs : 



1. In congestion of the head due to hyperemia of the 

 brain, encephalitis. The blood vessels are plainly marked in 

 tlie diffusely reddened conjunctiva. 



2. When the return of the venous blood from the head 

 is retarded. Characterized by distension of the veins. Occurs 

 in organic heart diseases, heart's weakness, pulmonary em- 

 physema. 



A diffuse, faded bluish-red discoloration of the conjunc- 

 tiva is found in conditions leading to an overcharging of the 

 blood with CO2. It is seen in febrile diseases (infectious 

 diseases), and wherever air is prevented from passing freely 

 into the lungs : diseases of the respiratory tract, respiratory 

 muscles, or heart. 



Inflammation of tlie mucous membrane of the gastro- 

 intestinal tract in the course of colic, produces a cyanotic con- 

 junctiva; if fever appears it becomes ramiform (a bad sign). 



Yellow (icteric) discoloration {jaundice) 

 is best observed on the scleral conjunctiva. It is not noticeable 

 by artificial light. If the conjunctiva is pale (bloodless), the 

 yellow can be more readily appreciated. The shades vary 

 from a mere trace of yellow to pronounced lemon yellow ; in 

 most cases combined with congestion. The icteric discolora- 

 tion is due to the abnormal amount of bile coloring matter 

 found free in the blood serum. 



According to the origin of the yellow coloring matter we 

 distinguish : 



1. Hematogenous icterus originates from a dissolution 

 of the red blood corpuscles, the coloring matter becoming set 

 free and mixing with the blood serum. Hematogenous icterus 

 is really a hemoglobinemia. The dissolved blood coloring 

 matter (the methemoglobin) is not changed to Ijib.- pigment 



