Stone in Bladder 4 1 1 



ureters to the pelvis of the kidney, where suppuration also takes place 

 and where more of the decomposing urine is pent up. Inflammation 

 extends thence through the gland, the tissue of which becomes riddled 

 with foul and scattered abscesses. Sometimes one of these abscesses 

 bursts through the capsule and sets up perinephritic suppuration. The 

 decomposing urine is taken up by the blood, and the patient's breath 

 has a strong ammoniacal odour. On tearing off the capsule at the 

 post-mortem examination close adhesions are found in many places 

 and small cortical abscesses are opened up. 



Vesical calculus. The pressure of the stone against the nervous 

 filaments on the floor of the bladder gives rise to the sensation of the 

 bladder containing an uncomfortable amount of urine, and thus fre- 

 quency of micturition is an early sign. By nig'ht the boy wets the 

 bed, and even during the day he may be unable to hold his water. The 

 sacral plexus supplies the sensory filaments, and by the internal pudic 

 nerve it also gives twigs to the end of the penis, to which spot 

 pain is often referred. (Similarly pain is referred to the knee in dis- 

 ease of the hip, the obturator nerve supplying each articulation, p. 358.) 

 During micturition the stone is driven against the sensitive trigone, and 

 the effort at once becomes urgent and distressing ; so violent is it that 

 the boy runs to the closet lest in voiding the urine he also evacuate 

 the rectum. Prolapse of the lining of the rectum occurs ; and blood, 

 and, later on, pus, may be mixed with the urine. Should the stone be 

 driven against the urethral opening of the bladder, and so suddenly 

 check the outflow of urine, the boy may scream with agony, but in 

 time he finds that this distress does not occur when he micturates in 

 the kneeling or horizontal posture, as the stone then falls away from 

 the neck of the bladder. 



The vesical sound should be formed of one piece of metal and 

 must possess a short and almost rectangular beak, so that the base of 

 the bladder, which may lie below the level of the prostate, may, with 

 every other mucous area, be thoroughly explored. (For lithotomy \ see 

 p. 443.) The floor of the bladder may be rendered more accessible to 

 the sound by raising it by the finger in the rectum, or by turning the 

 patient on to his side. 



Probably there is a centre for micturition and defecation in the 

 lumbar enlargement : 



From the bladder and rectum sensory filaments carry upwards the 

 messages of unrest, but the reflex circle is not necessarily at once put in 

 motion, for education and habit have placed the centre under the con- 

 trol of the will. But when the brain has lost the control, as in fracture 

 of the dorsal spine, and in cerebral or medullary disease, the patient un- 

 consciously ' passes everything under him.' The afferent impulse from 

 the mucous membrane is converted into a motor impulse, which passes 

 to the muscular coat, urging its contraction, the sphincters being at 

 the same time relaxed. When the nerve-lesion is so great that the 



