PRACTICAL CONSIDERATIONS : PROSTATE GLAND. 1981 



ing, and elongation of the prostatic urethra, or lateral deviation of that canal (if one 

 lobe greatly exceeds the other in size); {b) elevation of the vesical neck and outlet, 

 which are carried up by reason of their intimate connection *with the prostate, 

 especially with its median lobe, the base of the bladder remaining relatively un- 

 affected ; {c) the formation in this manner of a pouch or pocket (post-prostatic pouch) 

 in the bladder at a lower level than the vesical outlet. 



The indirect results of these conditions are the changes in the bladder occasioned 

 by {a) the mechanical obstruction which the enlarged prostate offers to the ready 

 and complete evacuation of its contents, {b) the circulatory disturbance incident to 

 pressure on the prostatic veins into which the blood from the vesical veins passes, 

 and iyC) septic infection. 



As a result of the narrowing or deflection of the urethra, the elevation of the 

 vesical outlet, and the formation of the post-prostatic pouch, the bladder is not 

 entirely emptied at each act of micturition, a certain amount of residual iiriyie remain- 

 ing behind. This may gradually increase as the obstruction becomes more marked, 

 ultimately causing dilatation of the bladder, zvith atony cansequent on partial de- 

 generation of, its muscular walls, or, in consequence of the more vigorous bladder 

 contraction required to empty the bladder, the trabeculae may become enormously 

 hypertrophied, the inner layers forming pronounced ridges. These by their con- 

 traction exert a povverfuL pressure upon the vesical contents, which, escaping very 

 slowly, transmit the pressure in all directions and occasion bulgings or sacculations 

 in such weak parts of the bladder-walls as are not supported by muscular bands or 

 by strong investing fasciae. The hypertrophy and sacculation are further encouraged 

 by the vesical irritability incident to venous congestion at the neck of the bladder, 

 which, as the prostatic veins become more obstructed, keeps up a condition of passive 

 hyperaemia and erethism more potent than residual urine alone to occasion the fre- 

 quently recurring desire to urinate and the muscular spasm of the sphincter at the 

 beginning of the act, which calls for such strong and repeated efforts on the part of 

 the detrusor muscles. 



Septic infection of a healthy mucous membrane by the pyogenic microbes caus- 

 ing acute or chronic cystitis is not possible, even although such bacteria are present 

 in the urine; when, however, the vesical mucous membrane is couQ-ested in conse- 

 quence of obstruction to venous return, and of distention of the viscus and frequently 

 recurring contractions of the detrusor muscles, it offers but slight resistance to the 

 microbic invasion. The pyogenic microbes are generally carried to the bladder by 

 dirty instruments, or, if these are rendered sterile, through failure to cleanse the 

 anterior urethra before the instrument is introduced into the bladder. Often cystitis 

 develops independently of the use of instruments, probably as a result of infection 

 conveyed by way of the urethral mucous membrane. 



2. The subjective symptoms brought about by these conditions may be briefly 

 summarized and will be readily understood by reference to the foregoing and to the 

 article on the bladder, (a) Frequent tirination, due partly to the inability completely 

 to empty the bladder, but chiefly to the venous congestion about the trigonum. {b) 

 Difficulty in starting urinatioyi, due to muscular spasm of the external vesical sphinc- 

 ter, which, excited by refle.xes from the hyperaesthetic prostatic urethra and neck of 

 the bladder, is not fully under the control of the will. A temporary reflex inhibition 

 of the detrusor muscles may also delay the act of urination, (r) Feeble 7irinatio?i, 

 due to the weakness, atony, or paresis of the overstretched detrusors, (d) Inter- 

 rupted urifiation, due usually to spasmodic contraction of the external vesical sphinc- 

 ter and compressor urethrae muscles, reflexly excited by urethro-cystitis ; occasionally 

 the result of intermittent contraction of the detrusors, often (as in many cases of 

 cardiac palpitation) a sign of beginning muscular atony. The physiology of micturi- 

 tion requires continuous contraction of the detrusor muscles and relaxation of the 

 sphincter y^r a brief interval only. When there is sufficient obstruction to triple or 

 quadruple the time normally required fully to empty the bladder, the detrusor mus- 

 cles, exhausted by their effort, may relax, whereupon the sphincter muscles, relieved 

 of the vis a tergo, promptly contract. After some seconds or minutes the detrusors 

 recover sufficiently to make further efforts at evacuation. (<?) Incontinence of urine, 

 which may always be taken as a symptom of retention with overflow, the intravesical 



