PARATHYROID GLANDS 



607 



K A K 

 C C 00 



NORMAL 



ANODAL 



pathological significance of the anodal opening contraction, however, ap- 

 peared to speak the fact that it is a very common occurrence. Its average 

 value, according to Mann, for 

 healthy children is given as s C c r Cf\ r 

 3.6 milliamperes. Von Pir- 

 quet believes, however, on the 

 ground of long continued ex- 

 aminations, that the appear- 

 ance of anodal opening 

 contractions with current 

 strengths below five milli- 

 amperes is a sign of a mild, 

 but nevertheless pathological, 

 hyperexcitability. He desig- 

 nates it briefly "anodal hyper- 

 excitability," because it be- 

 comes manifest at the anode, 

 to distinguish it from "katho- 

 dal hyperexcitability," which 

 is demonstrable at the 

 kathode. 



To kathodal hyperexcita- 

 bility von Pirquet reckons, 

 however, not simply, as Thie- 

 mich does, the appearance of 

 kathodal opening contraction 

 (KOC) below five milli- 

 amperes, but also the appear- 

 ance* of kathodal closure tet- 

 anus (KCTe) below this 

 stimulus threshold, since his 

 studies have shown that the 

 two responses are practically 

 equivalent in diagnostic 

 significance. 



Von Pirquet has happily 

 compared the four kinds of 

 contraction with four ther- 

 mometers of different, scales. 

 Thus, the kathodal opening 

 contraction (KOC) is a ther- 

 mometer in which the quick- 



cc. 

 



2 (a) 

 HYPEREXCITABILITY 



KATH- 

 ODAL 



Fig. 8. Types of galvanic excitability of 

 the motor nerves in sucklings. (After C. von 

 Pirquet, Wien. med. Wchnschr., 1907.) Findings 

 on testing the N. peroneus. On each excitation 

 state, two types are chosen, between which the 

 mean values tend to be met with. 1. Normal 

 excitability: Kathodal closure (KG) only, un- 

 der 5 Ma.; (&) KG and AC under 5 Ma/ This 

 is the normal finding in children at the end of 

 the first year of life, whereas younger children 

 usually approach type a. 2. Anodal hyper- 

 excitability: (a) KG and AO below 5 Ma., 

 (&) somewhat higher values; AC also. 3. Ka- 

 thodal hyperexoitability : (a) KG, AC, AO also 

 KCTe at 5 Ma., the latter indicated in the 

 column of Kathodal opening by an inverted 

 carat; (&) typical Thiemich reaction: All four 

 qualities, the kathodal opening at 1.7 Ma. 



silver becomes visible first at 39 ; with its aid we can recognize only a high 

 "galvanic fever." For recognizing "subfebrile galvanic temperatures/ 7 if 



