Two circulatory routes within the human corpus cavernosum penis: a scanning electron microscopic study of corrosion casts.

The microvascular architecture of the human corpus cavernosum penis was studied by scanning electron microscopy of vascular corrosion casts. The corpus cavernosum was supplied by the penile deep artery. It gave off branches to become either arteries distributed within the corpus cavernosum or those directly supplying the corpus spongiosum urethrae. The former arteries further divided into small arteries which fell into two categories: 1) arteries breaking up into capillaries, and 2) arteries draining directly into the cavernous sinuses. The capillaries were collected into venular networks just beneath the tunica albuginea (the subalbugineal venular plexus), while the cavernous sinuses were collected into venules at the periphery of the corpus cavernosum. These postcavernous venules also received venules from the subalbugineal venular plexus, and left the corpus cavernosum. Thus, two circulatory routes are evident within the corpus cavernosum. These findings suggested that the penile erectile cycle is controlled by hemodynamic changes between these two routes within the corpus cavernosum.

Quantitative analysis of outflow pathway of corpora cavernosa by pressure flow technique.

Using a pressure flow technique, quantitative analysis of the physiological characteristics of the outflow pathway of the corpus cavernosum was carried out in 19 male dogs weighing 7.5 to 23.0 kg. Pressure flow curves were made on dogs whose pelvic nerve was stimulated electrically and on dogs left unstimulated. When a cyclical change in saline perfusion rate was applied without nerve stimulation, the variable of the intracorporeal pressure showed a large hysteretic loop, indicating that the resistance of the outflow canals to flow was altered by the distension of the sinusoidal space. In dogs whose pelvic nerve was stimulated, the pressure flow curves shifted to the left side in comparison with the outward phase of the pressure flow curve of animals without pelvic nerve stimulation, and this curve piled on the returning phase. No hysteretic relation was observed between the outward and returning phase of the pressure flow curve with pelvic nerve stimulation, but in the detailed analysis, in which the % flow rate was used instead of actual flow rate of saline perfusion, a small hysteretic loop based on the difference of the elasticity of the outlet canals was found. The distension of the corpora cavernosa and the pelvic nerve electrostimulation probably act as the triggers of the same occlusive mechanism in the outflow pathway. The percentage decrease in the blood flow in the outflow canal of the corpus cavernosum induced by the distension of the sinusoidal space or by the pelvic nerve electrostimulation was 69.6 +/- 14.4% (mean +/- SD).

Human penile hemodynamics studied by a polarographic method.

Observations of the tissue oxygen tension alteration were made using an open tip type oxygen electrode polarographic method as an index of blood flow change in the penile skin, corpus cavernosum and thigh skin of 16 males aged 20-26 years (average age: 20.5 years). In another five males aged 18-21 (average age: 19.8 years) the relationship between corpus cavernosum tissue oxygen tension alteration and penile circumference change in the erection process was observed. This relation was obtained in the penile circulation model, and penile hemodynamics were ascertained. In the flaccid penis the corpus cavernosum contains low-oxygen blood and there is a blockade at the vascular tree in the corpus cavernosum. In the tumescence phase the blood flow of the corpus cavernosum increased suddenly by the relief of cavernosum vascular blockade. During the penile tumescence phase the increased inflow and outflow persisted in corpus cavernosum, and in penile skin the blood also increased initially, but gradually decreased as penile circumference increased. After erection was attained it is thought that resistance to inflow occurred by outflow pathway contraction. In the detumescence phase, a decrease of inflow and a concomitant increase of outflow occurred and the reopening of outflow is thought to be necessary for prompt penile detumescence.

[Clinical experience of norfloxacin in urinary tract infection].

Norfloxacin (NFLX) was administered to outpatients and inpatients with urinary tract infections at our department. Clinical efficacy and safety were evaluated in 50 patients by the criteria for evaluation of clinical efficacy of antimicrobial agents on urinary tract infection. Overall clinical efficacy for 17 cases with acute simple cystitis was excellent in 13 cases, moderate in 4 cases with an effectiveness rate of 100%. The overall clinical efficacy for 33 cases with chronic complicated UTI was excellent in 18 cases, moderate in 6 cases and poor in 9 cases with an effectiveness rate of 73%. The eradication rate of 21 strains from acute simple cystitis patients was 100%. Forty four out of 60 strains from chronic complicated UTI patients were eradicated and the eradication rate was 73%. Neither subjective nor objective adverse reactions were observed in 50 patients. Abnormal changes in laboratory tests were found in 8 patients, but were probably not related to NFLX administration. Judging from these results, NFLX is considered to be an effective and safe antibacterial for the treatment of UTI.

[Experience in using a ureterorenoscope in 14 cases].

We carried out studies using an ureterorenoscope in 14 cases, including 13 patients suffering from an ureteral stone. The stone was smaller than 1 cm and existed in lower and middle portion. The other patient had a foreign substance, which was a double J-stent catheter that had been passed into the middle portion of the ureter accidentally. Initially, the size and course of ureter, the position of stone and foreign substance were ascertained using a retrograde pyelogram. The patients were placed in a lithotomy position under spinal anesthesia or epidural anesthesia. The ureterorenoscope was inserted into the bladder through urethra and the instrument was further extended through ureteral orifice and ureteral lumen to the position of the calculus or foreign substance while observing the procedure. Once the calculus or foreign substance was observed, a 4F Pfister-Schwartz stone retriever or forceps was inserted through working channel. After coming in contact with the stone or foreign substance, the matter was removed while observing it with the scope. The foreign substance and 77% of the stones observed were removed by this procedure and the usefulness of the ureterorenoscope was successfully demonstrated in the cases. However, on the other hand, of these 14 cases, 2 (14%) experienced ureteral injury. In one case, the ureter was penetrated by the scope; and in another, injury occurred during the biopsy of the ureteral wall. Therefore, it is our opinion that more careful use of the ureterorenoscope is necessary to prevent these types of injuries.

[Evaluation of neurogenic bladder in patients with spinal cord injury using a CMG.EMG study and CMG.UFM.EMG study].

Simultaneous recording of intravesical pressure, sphincter electromyography and uroflowmetry (CMG.UFM.EMG study) was performed following cystometry simultaneously with electromyography (CMG.EMG study) on 20 patients with spinal cord injuries. Differences in the influence to micturition between the CMG.EMG study and CMG.UFM.EMG study is thought to be due to whether the catheter is indwelling in the urethra or not. We examined those differences and patient's rehabilitation maneuver (Cred'e maneuver). Micturition pressure and opening pressure measured by the CMG.EMG study were larger than that measured by the CMG.UFM.EMG study (P less than 0.05, P less than 0.01 respectively). Incidence of detrusor-sphincter dyssynergia measured by the CMG.EMG study was greater than that measured by the CMG.UFM.EMG study in the detrusor hyperreflexic cases. The Cred'e maneuver caused increase in opening pressure, micturition pressure and peak flow rate, but the voiding volume and voiding time did not increase to any effective extent. The Cred'e maneuver exaggerated the detrusor sphincter dyssynergia.