CHESS classification of bladder-outflow obstruction. A consequence in the discussion of current concepts

The present discussion on the natural history, growth rate pathophysiology, morbidity, and possible treatment of benign prostatic hyperplasia (BPH) reinforces the need to objectify mechanical BPH-induced obstruction with pressure-flow study. Different methods for the quantification of BPH-induced obstruction exist and the grade of simplification depends on their working mechanism. To review the limitations of the current concepts, 118 BPH patients were selected for computerized pressure-flow data analysis according to quadratic passive urethral resistance relation (PURR) function. The CHESS classification differs from all other concepts due to its two-dimensional character and was developed as a result of the following way of thinking: (1) the whole individual pressure-flow plot is the most accurate basis for further analysis; (2) PURR as the true low-pressure flank of the individual plot is the most favorable definition for mechanical obstruction; (3) PURR quantification requires at least two parameters, footpoint and curvature/slope, with regard to the documented missing significant correlation of both; and (4) a two-parameter-based classification is two-dimensional (CHESS classification).

[Thermotherapy of benign prostatic hyperplasia]

Transurethral microwave thermotherapy (TUMT) differs from hyperthermia in the higher intraprostatic temperatures reached and in the irreversible damage it causes to intraprostatic tissue. Both subjective symptoms and objective data, such as peak flow and residual urine, are influenced differently by TUMT and by sham treatment. As expected, no improvement of the objective data was documented with TUMT, in contrast to transurethral resection of the prostate (TURP), whereas the improvement in subjective symptoms was comparable. The complication rate in terms of morbidity is clearly lower with TUMT than with TURP. TUMT can be performed as an outpatient procedure without a general anaesthetic. TUMT had a specific effect on outflow obstruction, but it was less pronounced than that achieved with TURP. Therefore, TUMT is indicated for patients with typical symptoms of BPH and a mild mechanical obstruction. In this patient group TUMT seems to be the optimal treatment, whereas TURP would constitute "overtreatment" owing to its higher complication rate and the unnecessary tissue resection. At this stage of BPH, TURP is justifiable only with reservations; it should be reserved for BPH with moderate and severe mechanical obstruction.

Effects of magnesium citrate and phytin on reducing urinary calcium excretion in rats

The aim of this study was to determine and compare the effects of both magnesium citrate and phytin on reducing urinary calcium excretion under high-calcium-diet conditions during single and combined treatments. An animal experiment was carried out over a period of 4 weeks in 35 male rats. Urinary calcium excretion was reduced significantly by magnesium citrate and/or phytin in rats fed on high-calcium diets. The hypocalciuric effect of magnesium citrate was more evident than that of phytin. Urinary magnesium excretion was high in all experimental groups. However, the urinary magnesium/calcium ratios showed a consistent increase only in the groups treated with magnesium citrate. Urinary citrate excretion showed a relative increase with the introduction of magnesium citrate plus phytin; however, in both the high-calcium-diet group and the magnesium-citrate group this was found to be reduced. Urinary phosphate excretion was slightly higher in the groups treated with phytin. There was no definite difference in urinary oxalate concentration between the groups. No significant change was noted in the serum concentration of calcium, magnesium, or phosphate.

[Results of surgical therapy for venous insufficiency as a cause of erectile disorders]

Since penile vein ligation is usually associated with a poor postoperative outcome, a study was undertaken to evaluate possible prognostic factors for this procedure. A total of 44 patients with erectile dysfunction underwent ligation of all dorsal penile veins and resection of the deep dorsal penile vein for venous impotence. A comprehensive study of all patients was made. All patients did not respond to pharmacotherapy and had a venous leak. With a minimum follow-up period of 6 months, patients were categorized as follows: full spontaneous erections, those patients responding to pharmacotherapy and those showing no improvement. Out of 44 patients, 13 had full spontaneous erections postoperatively, 5 now responded to pharmacotherapy and 26 showed no improvement. The maintenance flow was 89 +/- 50 ml/min in the group with spontaneous erections and 85 +/- 49 ml/min in those showing no improvement (P = 0.78). Out of the 20 patients with normal single potential analysis of cavernous electric activity (SPACE), 12 had full erections postoperatively, 4 showed no improvement and 4 responded to pharmacotherapy. Of the 24 patients with abnormal SPACE, 1 developed full erections, 1 now responds to pharmacotherapy and 22 showed no improvement. Our results indicate that SPACE seems to be an important prognostic factor for the postoperative outcome of penile vein ligations for venous impotence.

Intracavernous application of SIN-I in rabbit and man: functional and toxicological results

The mode of action of the active metabolite SIN-I of the vasodilator prodrug molsidomine was studied in vitro and in vivo in corpus cavernosum of rabbit and man. SIN-I produces a dose-dependent relaxation of isolated human cavernous smooth muscle strips. In the rabbit, the intracavernous application of SIN-I increased the intracavernous pressure to a full erection (approximately 100 cm H2O). This response was highly reproductible. SIN-I was also injected intracavernously 6 times in five rabbits over 2 weeks; no inflammatory or fibrotic reactions were found on histology. SIN-I may be a reliable drug for the treatment of impotence without side-effects.

Significant obliteration of the urethral lumen after Wallstent implantation

The permanently implanted self-expandable urethral stent (Wallstent) has found increased use in patients with recurrent urethral strictures because of its simple implantation technique. To date there have been no reports of serious complications. At 6 weeks after stent implantation our patient had complete luminal obstruction. This complication demonstrates the need for short-term controls after implantation of a urethral stent.

Preliminary results with the nitric oxide donor linsidomine chlorhydrate in the treatment of human erectile dysfunction

Recent experimental studies showed an important role of endothelium derived relaxing factor for cavernous smooth muscle relaxation. Since nitric oxide seems to account for the biological actions of endothelium derived relaxing factor, a study was done to examine a possible role of the nitric oxide donor linsidomine chlorhydrate (SIN-1) in the treatment of erectile dysfunction. To determine a therapeutically useful dose 0.1, 0.2, 0.5 and 1 mg. SIN-1 were injected intracavernously in patients with erectile dysfunction. Each dose was given to 2 patients. Then, 63 patients received 1 mg. SIN-1, including 7 who had prolonged erections to minimal doses of papaverine plus phentolamine and 4 who did not respond with a full erection to other pharmacological agents. Intracavernous injection of SIN-1 induced a dose-dependent erectile response by increasing the arterial inflow and relaxing cavernous smooth muscles. Of the patients 29 had a full, 21 an almost full and 13 a moderate erection to 1 mg. SIN-1. There were no systemic or local side effects. In the patients with prolonged erections to papaverine plus phentolamine the mean duration of a full erectile response to SIN-1 was 57 minutes. Compared to the responses to a papaverine (15 mg./ml.) and phentolamine (0.5 mg./ml.) mixture, the erection induced by SIN-1 was superior in 10, comparable in 47 and inferior in 6 patients. Our data suggest a possible role for SIN-1 in the treatment of erectile dysfunction. Possible advantages may be that erection is induced by a mechanism similar to that occurring physiologically, a decreased risk of inducing prolonged erections and low therapy costs.