HARRIS, CONSTANTINOU AND STAMEY
in men for risk of causing impotence. 5 Clearly, more research is needed to understand the mechanisms and causes of detrusor instability for only then can we hope to develop more effective and lasting treatments for men and women. REFERENCES 1. Harris, W.: An analysis of 1,433 cases of paroxysmal trigeminal
5. 6. 7.
neuralgia (trigeminal-tic) and the end-results of gasserian alcohol injection. Brain, 63: 209, 1940. Jefferson, A.: Trigeminal root and ganglion injections using phenol in glycerine for the relief of trigeminal neuralgia. J. Neurol. Neurosurg. Psychiat., 26: 345, 1963. lngelman-Sundberg, A.: Urge incontinence in women. Acta Obst. Gynaec. Scand., 54: 153, 1975. Ewing, R., Bultitude, M. I. and Shuttleworth, K. E. D.: Subtrigonal phenol injection therapy for incontinence in female patients with multiple sclerosis. Lancet, 1: 1304, 1983. Blackford, H. N., Murray, K., Stephenson, T. P. and Mundy, A. R.: Results of transvesical infiltration of the pelvic plexuses with phenol in 116 patients. Brit. J. Urol., 56: 647, 1984. Constantinou, C. E.: Principles and methods of clinical urodynamic investigations. Crit. Rev. Biomed. Eng., 7: 229, 1982. Constantinou, C. E.: Resting and stress urethral pressures as a clinical guide to the mechanism of continence in the female patient. Urol. Clin. N. Amer., 12: 247, 1985. Warrell, D. W.: Vaginal denervation of the bladder nerve supply. Urol. Int., 32: 114, 1977. Freiha, F. S. and Stamey, T. A.: Cystolysis: a procedure for the selective denervation of the bladder. J. Urol., 123: 360, 1980. Torrens, M. and Hald, T.: Bladder denervation procedures. Urol. Clin. N. Amer., 6: 283, 1979. Clarke, S. J., Forster, D. M. C. and Thomas, D. G.: Selective sacral neurectomy in the management of urinary incontinence due to detrusor instability. Brit. J. Urol., 51: 510, 1979. EDITORIAL COMMENT
This study is interesting from a number of standpoints and it originates from a group that has made many fine contributions to the urodynamic literature. As one of the initial reviewers of this article I was asked to contribute an editorial comment, I suspect because of some of the reservations that I had expressed regarding this procedure and its applicability to neurologically normal patients. Although this article does make important points, I nevertheless believe that it demonstrates the old adage that some individuals regard a partially filled container as being half full, while others regard it as being half empty. There are, indeed, many treatments for storage failure secondary to detrusor hyperactivity or sensory urgency and the authors have chosen a subset of patients in whom pharmacological therapy has failed. However, one must question whether the results and complications in these patients justify recommending this procedure as the next step after failed drug therapy in patients with detrusor hyperactivity without causative neurological disease. If one does not exclude the patient who required urinary diversion from the evaluation of results and even if one ignores the fact that the followup was subjective except for repeat cystometry within 2 months after treatment, then the failure rate in my estimation is as low as 40 per cent (patients 3, 7, 9 and 10). This ignores the fact that an additional patient (patient 8) whose final result I would characterize as a great success required a subsequent vesicovaginal fistula repair and vesicourethral suspension. The rate of vesicovaginal fistula formation troubles me greatly despite the fact that the authors cite mitigating factors and that "these occurred early in our series". In table 3 one sees that patient 8 was not one of the earlier patients and she also was not one of the patients in whom a large amount of ethanol was injected. If one discounts the fistula formation in patients 3 and 7, then there still is 1 of 8 patients who had a vesicovaginal fistula fairly late in the series with injection of an amount of ethanol that did not seem to be excessive. In my opinion a vesicovaginal fistula rate of 12.5 per cent still is unacceptable. Some issues regarding stress urinary incontinence in this series, in my opinion, also must be addressed. McGuire and Savastano reported that patients with a combination of stress urinary and urge inconti-
nence often are cured of the urge incontinence by repair of the stress incontinence. 1 In view of the complications in the current series, may it not be justifiable to recommend that patients with significant stress and urge incontinence undergo repair of the stress incontinence initially by a relatively simple procedure with little morbidity, and that the urge incontinence should be treated in those in whom it persists? Another factor relative to stress incontinence requires mention, that is the potential for development or worsening of stress incontinence subsequent to subtrigonal ethanol injection. If one eliminates the patients who received a simultaneous vesicourethral suspension (patients 1 and 6) and the patient who required urinary diversion (patient 7), then 2 of the remaining 7 patients required subsequent suspension because of significant worsening (or development) of the stress incontinence. This 28 per cent figure seems to be high but it may be entirely understandable when one considers the potential effects of the ethanol injection. It is hard to imagine that the alcohol does not affect the neural supply to the smooth and striated sphincter, as well as its intended effects on the bladder innervation. It also is hard to believe that none of these patients experienced any change in perineal or vaginal sensation, and in a sexually active population this must be an important medical and legal consideration. Regardless of which definition of detrusor instability is used (the one in the text or the one in the footnote to tables 1 and 2), the treatment of nonneuropathic detrusor instability after failure of pharmacological management is, indeed, difficult. The authors have pursued one of the alternatives, perivesical denervation with subtrigonal injection of ethanol, and they have reported the results objectively. Doubtless with further refinements in patient selection and methodology (a suggestion might be the inclusion of a test dose of local anesthetic to improve results further), this procedure might, indeed, compare favorably to alternative modalities. However, based upon the results reported it is questionable, in my opinion, that this, indeed, represents a "safe and relatively simple procedure that is less invasive than the other surgical modalities currently available". AlanJ. Wein Division of Urology, 5-Silverstein Hospital of the University of Pennsylvania Philadelphia, Pennsylvania 1. McGuire, E. J. and Savastano, J. A.: Stress incontinence and detrusor instability/urge incontinence. Neurourol. Urodynam., 4: 313, 1985. REPLY BY AUTHORS We share Doctor Wein's appropriate concern over the high incidence of vesicovaginal fistulas. The fistula in patient 8 was a disappointment but preoperatively she was in diapers and had given up an executive position. She is still dry and a grateful patient 3 years after the alcohol injection. Recently another fistula developed in an even younger woman in whom 50 ml. 50 per cent ethanol also were injected subtrigonally. Cystoscopically, there was no elevation of the trigonal submucosa and the bladder base was vigorously massaged against the cystoscope to prevent alcohol accumulation in localized areas, a procedure we were not doing at the time of injection in patient 8. We do not agree that urethral suspension for detrusor instability of this severe degree, even in the presence of minimally demonstrable stress incontinence, would have benefited these patients. We have cured more than 600 patients with stress incontinence by endoscopic suspension of the vesical neck: two-thirds of these patients have a history of some urgency incontinence and a third have documented detrusor instability preoperatively. However, these patients are not like the 10 reported in our study, all of whom had incapacitating detrusor incontinence. The stress incontinence demonstrated in these 5 patients was minimal, accounting by history for less than 5 per cent of the total urinary loss. As high as our complication rate is, what are the alternatives? We have reviewed them and they appear to be an unsatisfactory solution for this small subgroup of patients. Indeed, this is the major failure of 20 years of urodynamic research, that is we have no decent solution for the patient with severe detrusor incontinence. Until that solution becomes apparent we will continue to inject alcohol beneath the trigone but carefully explain to the patient that a vesicovaginal fistula is a genuine risk and that a hemi-Kock pouch with urethral anastomosis ultimately may be required.