412 NELSON W. JANNEY 



age of ''marasmus" (cretinism?). It is suggested that the marked fre- 

 quency in thfs family of disorders of the skin appendages and nervous 

 system may ultimately be related to their common embryologic origin in 

 the neuroectodermal genii layer. 



The Peripheral Nervous System suffers Jikewise. Anesthesias are 

 infrequent, though myxedemic patients may complain of numbness of fin- 

 gers, etc., from cutaneous infiltration. Parasthesias, usually itching and 

 burning of the skin, are at times complained of. Aching in the back, 

 shoulders and extremities is not uncommon. Involvement of the motor 

 nerves contributes to the muscular weakness. Rudinger and Falta report 

 a diminished irritability to the electric current in experimental athyrosis, 

 and Erb observed the same condition in myxedema cases. It is very likely 

 that nerve regeneration after injury in severely affected patients would, 

 on investigation, be found to be delayed in hypothyroidism in view of the 

 positive experimental finding on record in this regard. The deep reflexes, 

 though retained, are often weak, due in part to the poor nutrition of the 

 musculature. 



The autonomous nerves in thyroid disease have been the subject of 

 various studies by the Vienna School of clinicians in seeking support for 

 their reciprocal hypothesis of endocrin function. Owing to the defective 

 state of nutrition, all drug reactions on the autonomous nerves have an 

 unusually long duration. Included are the miotic reaction of pilocarpin, 

 mydriatic action of atropin, and homoatropin. elimination of vagal func- 

 tion by atropin. 



Organs of Special Sense. The olfactory sense may be greatly defi- 

 cient. Hero, as in all the organs of special sense, the question arises 

 as to how much defect be present in the peripheral sense organ or in the 

 cerebral center for the same. 



The eye is subject to various degenerative changes. In athyrosis near 

 blindness may bo caused by imperfect development of the uveal tract. 

 Perhaps this may be the explanation of the lack of light sensitiveness which 

 has boon noted in cretins who may pass hours undisturbed by strong sun- 

 light. W. Xontmayer calls attention to the experimental production, by 

 moans of thyroidootomy, of koratitis, necrosis of the cornea, blepharitis and 

 conjunctivitis. After stninieotomy in man, papilledema and cataract 

 have, developed. Risley reports good results in interstitial keratitis, and 

 Her. I lev in malignant uveitis with thyroid medication. Congenital catar- 

 act had IxH-n observed by Schioetz in cretinous calves. 



Taste is frequently deficient. 



Ihtinmj is loss often altered than in endemic cretinism, though severe- 

 v affected sporadic; cretins may become very deaf. In myxedema, also, the 

 earing may -row ( inll. F ()1 - the causes of these disturbances, see section 

 athology. 



>>'cr//. is of course lost when hearing is defective. Cretins may be 



