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young adults. Cardiologists should recognise this condition and include the sequelae of KD in the differential diagnosis of early-onset coronary artery disease in adults. We thank all the adult cardiologists who kindly sent us patient information. This study was done partly as a project of the Kawasaki Disease Research Committee supported by the Ministry and Welfare of Japanese Government. We thank the Committee members; Dr Masayoshi Yanagisawa, Dr Junro

Hosaki, Dr Siro Naoe, Dr Masahiro Endo, Dr Yasuo Takeuchi, Dr Hiroyuki Nakano, Dr Tetsuro Kamiya, Dr Soichiro Kitamura, Dr Kunizo Baba, Dr Kiyoshi Baba, and Dr Satoshi Shirahata for their comments and help. REFERENCES 1. Kawasaki T. Acute febrile mucocutaneous lymph node syndrome (in Japanese). Allergy 1967; 16: 178-222. 2. Kato H, Koike S, Yamamoto M, Ito Y, Yano E. Coronary aneurysms in infants and young children with acute febrile mucocutaneous lymph node syndrome. J Pediatr 1975; 86: 892-98. 3. Kato H, Ichinose E, Takechi T, Yoshioka F, Suzuki K, Rikitake N. Fate of coronary aneurysms in Kawasaki disease: serial coronary angiography and long-term follow-up. Am J Cardiol 1982; 49: 1758-63. 4. Sakai Y, Takayanagi K, Inoue T, et al. Coronary artery aneurysms and congestive heart failure; possible long-term course of Kawasaki disease in an adult: a case report. Angiology 1988; 39: 625-30. 5. Ishiwata S, Fuse K, Nishiyama S, Nakanishi S, Watanabe Y, Seki A. Adult coronary artery disease secondary to Kawasaki disease in childhood. Am J Cardiol 1992; 69: 692-94. 6. Kato H, Ichinose E, Kawasaki T. Myocardial infarction in Kawasaki disease: clinical analyses of 195 cases. J Pediatr 1986; 108: 923-27.

ADDRESSES: Departments of Pediatrics (Prof H Kato, MD, O. Inoue, MD) and Internal Medicine (H. Toshima, MD), Kurume University School of Medicine; Kawasaki Disease Research Information Center (T. Kawasaki, MD); Department of Internal Medicine, Kyoto University School of Medicine (H. Fujiwara, MD); and Department of Internal Medicine, Aichi Medical School (T. Watanabe, MD), Japan. Correspondence to Prof Hirohisa Kato, Department of Pediatrics, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830, Japan.

Electrically stimulated gracilis sphincter for treatment of bladder sphincter incontinence

Correction of total urinary incontinence due to sphincter damage is done with an artificial sphincter prosthesis or urinary diversion. In this pilot study we used graciloplasty around the bladder neck followed by electrical stimulation of this muscle with an implanted stimulator, which could be switched off and on by a magnet. Stimulus variables could be changed externally. With the stimulator on, urethral pressures of about 50 cm H2O were obtained. Of three patients who underwent the procedure, two became continent and one improved but remained

incontinent. Dynamic graciloplasty urinary incontinence.

can

restore

Lancet 1992; 340: 1129-30.

Total urinary incontinence is the result of incompetence of the bladder sphincter mechanism. Since direct surgical correction is not possible, treatment is by urinary diversion

application of an artificial sphincter prosthesis. Although the results with the existing artificial sphincter prosthesis AMS 800 (Pfizer, New York, USA) are satisfactory, there are two main disadvantages-possible infection of this foreign body or pressure necrosis of the urethra. The pressure of the balloon encircling the urethra can be accommodated by the pressure in the reservoir, but or

the

the tension around the urethra can be established once only-ie, at the time of operation. We and other investigators have reported good results with electrical stimulation of skeletal muscles in dynamic cardiomyoplasty1 and in dynamic graciloplasty for faecal incontinence.2 In these muscles, a change from fast-twitch to slow-twitch muscle fibres was seen in biopsy samples after 2 months of stimulation. We report a pilot study with the same technique in three patients with complete urinary incontinence and a stable detrusor. The procedure is as follows. During the first operation, the gracilis muscle is transposed. Through a thigh incision, the muscle is freed, and at the level of the tuberositas tibiae is detached from its peripheral attachment. Vascularisation and innervation, which enter close to the origin of the muscle, are carefully left intact. The bulk of the muscle and the distal tendon are brought out through a perineal incision. During this procedure, a second operating team has (through a lower abdominal incision), prepared the bladder neck and proximal urethra as in conventional surgery for placing an artificial sphincter. Working from both sides, the surgeons open the urogenital diaphragm in the upper attachment to the os pubis by incising the periostium. A foramen is carefully created with attention not to disturb the neurovascular bundle to the penis. In all three patients we could create a foramen big enough to pull the gracilis muscle into the cavum retzii. The muscle was pulled around the bladder neck in a full circle, and in all patients could be used as a sphincter. The tendon was anchored to the back of the os pubis with

non-resorbable sutures. We left an interval of at least 6 weeks before the final stage of the procedure, so that the gracilis tendon would grow tightly to the os pubis and the vascularisation of the gracilis muscle could adapt to the new situation. Then, the contractility of the muscle was tested by external stimulation and simultaneous urethral pressure profile

(UPP) measurements. At the second operation, 6 weeks to 4 months later, a small incision was made over the most proximal part of the gracilis at the thigh. With temporary testing needles connected to an external stimulator (PS 5300, Medtronic, Minnesota, USA), the point of minimum threshold was located. An intramuscular electrode (SP 5528, Medtronic, Maastricht, Netherlands) was implanted close to the entry point of the nerve. The anode was placed 4 cm from the cathode. The leads were then tunnelled to a subcutaneous pocket in the lower abdomen and connected to an implantable stimulator (Itrel II, Medtronic, Minnesota, USA). The muscle was activated immediately after implantation in an intermittent mode as has been previously described.2 The output of the electrical stimulator and thus the contractions of the new sphincter could be switched off with a magnet to allow micturition at a convenient time. Patient 1-A 24-year-old man had been incontinent for 5 years after a severe accident with pelvic fracture and total urethral rupture. At that time he was treated with catheter traction for 6 months. Soon afterwards, he developed a urethral stricture at the level of the external sphincter. After three internal urethrotomies he was totally incontinent. Because of recurrent strictures, we did a urethroplasty with split-skin 6 months before the graciloplasty. Shortly before the planned operation urethrocystoscopy revealed the urethra wide open. The external sphincter and bladder neck were destroyed, and there was no continence mechanism. Urodynamically he had a stable bladder with a 250 ml capacity. During graciloplasty we encountered difficulties creating a foramen through the scarred area of the urogenital diaphragm, but by sharp dissection in the upper corner as well as dilatation we got the bulk of the gracilis muscle into the cavum retzii, encircled the bladder neck, and attached the tendon to the pubic bone. 3 months later the neurostimulator was implanted.

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Patient 2-This 21-year-old man had been totally incontinent since birth because of congenital epispadias. Shortly after birth the epispadias was provisionally closed, but he remained totally incontinent. At evaluation he had a very small bladder capacity (50 ml) and reflux in both ureters. However, both kidneys were normal. We performed subtotal cystectomy (leaving the trigone intact and replacing the detrusor by ileum) and graciloplasty at the level of the bladder neck. The ureters were implanted in the neobladder according to the LeDuc method. The urethra was closed up to the top of the penis. A bladder-cutaneous fistula, which developed postoperatively, closed spontaneously. The gracilis muscle remained vital without any problems during this fistulisation. The stimulator was implanted 4 months after the first

operation. Patient 3-5 years previously, this 62-year-old man became incontinent after a transurethral resection of the bladder neck and prostate, which had damaged the external sphincter. Urodynamically his bladder was stable and had a 300 ml capacity. At cystoscopy, the external sphincter and the bladder neck were wide open. The bladder was normal. Graciloplasty was uneventful. 6 weeks later the stimulator was implanted. All 3 patients were evaluated at baseline and every 2 weeks for 12 weeks. A questionnaire was used to record improvement of continence as evidenced by use of incontinence pads and the frequency of micturition. Urodynamic investigations, including UPP, were done before the procedure, 6 weeks after the muscle implant, and 3 months after the neurostimulator activation. Muscle fibre changes were not assessed. The study was approved by the medical ethics committee of the Academic Hospital, Maastricht.

Improvement of continence was first seen after the transposition in patients 1 and 2. At cytoscopy before implantation of the neurostimulator, the gracilis muscle bulged into the urethra like an external sphincter. However, the muscle did not close the urethra entirely. Patient 1-The bladder remained stable with good capacity. Initial UPP was 0 cm H2O, increasing to 20 cm H2O after gracilis transposition. With electrical stimulation, the UPP increased to 50 cm H2O. He was almost completely continent; he did not use any pads, but reported some drops in his underwear, mainly stress induced. Follow-up was 9 months. Patient 2-The urodynamic evaluation 3 months after the ileocystoplasty showed bladder capacity of 400 ml and no unstable contractions. There was no reflux on Initial UPP was 0 cm H2O and 15 cm H2O cystography. after gracilis transposition, increasing to 40 cm H20 3 months after the stimulator implant. He could complete micturition to a residue of 20 ml by abdominal pressure and was fully continent. Follow-up was 7 months. Patient 3-Urodynamic evaluation showed a stable bladder and an increase in UPP from 15 to 22 cm H2O. After implantation of the electrical stimulator, the resting pressure increased from 22 to 60 cm H2O with stimulation on. He remains incontinent, although the number of pads decreased from five to two per day. He also had a good micturition stream. He is dry at night. Follow-up was 5 months. Our results show that an electrically stimulated gracilis muscle may be used as a bladder sphincter. The advantage over an artificial sphincter prosthesis is that it is autologous material with less chance of infection. Moreover, contraction pressures can be adapted because the activity of the stimulator can be changed telemetrically, so that

contractions sufficient to maintain continence can be used, with less chance of necrosis of the bladder neck. Chronic stimulation of skeletal muscle has been studied experimentally in animals and man,2-5 but not to our knowledge in urinary incontinence. In laboratory animals, chronic low-frequency stimulation of skeletal muscles results in a transition of fast-twitch to slow-twitch fibres; this change occurs within a few weeks.6 The contraction force of the slow-twitch fibres is lower than that of the fast-twitch fibres, but they are much more able to sustain longlasting activation. We tried to obtain this change by slowly increasing the stimulator-on time. The stimulus strength needed to obtain sufficient contraction was such that no damage by electrochemical reactions was expected.6 Because the induced muscle contractions are longstanding and not accompanied by a gross displacement of the muscle, the risk of mechanical damage of the leads seems to be small. Usually there is a formation of fibrotic tissue around the implanted electrodes, but others have not found this to be a serious difficulty.7 In man, the diameters of fast-twitch and slow-twitch fibres are almost the same. In the long term, however, hypertrophy may occur because of the continuous activation of the muscle,8 leading to obstruction of urinary flow, but this has not yet been seen in our patients. Our findings have encouraged us to continue studies on dynamic graciloplasty for urinary incontinence. We thank the scientific and technical support of Mr I. Bourgeois and MrA. Habets (Bakken Research Center Maastricht). This study was made possible by the financial support of the Ministry of Trades and Industry, Netherlands

(STIPT-project). REFERENCES 1.

Chachques JC, Grandjean PA, Carpentier A. Dynamic cardiomyoplasty: experimental cardiac wall replacement with a stimulated skeletal muscle. In: Chiu RCJ, ed. Biochemical cardiac assist: cardiomyoplasty and muscle-powered devices. New York: Futura Publishing, 1986:

59-84. 2. Baeten CGMI, Konsten J, Spaans F, et al. Dynamic graciloplasty for treatment of faecal incontinence. Lancet 1991; 338: 1163-65. 3. Hallan RI, Williams NS, Hutton MRE. Electrically stimulated sartorius neosphincter: canine model of activation and skeletal muscle transformation. Br J Surg 1990; 77: 208-13. 4. Bobechko WP, Herbert MA, Friedman HG. Electrospinal instrumentation for scoliosis: current status. Orthop Clin North Am 1979; 10: 927-41. 5. Acker MA, Mannion JD, Stephenson LW. Methods of transforming skeletal muscle into fatigue-resistant state: potential for cardiac assistance. In: Chiu RC, ed. Biomedical cardiac assist: cardiomyoplasty and muscle-powered devices. New York: Futura Publishing, 1986: 19-27. 6. Mortimer JT. Motor prostheses. In: Brooks VB, ed. Handbook of physiology: the nervous system. Bethesda: American Physiological Society, 1981: 155-87. 7. Baeten C, Spaans F, Fluks A. An implanted neuromuscular stimulator of fecal continence following previously implanted gracilis muscle: report of a case. Dis Colon Rectum 1988; 31: 134-37. 8. Munsat TL, McNeal D, Water R. Effects of nerve stimulation on human muscle. Arch Neurol 1976; 33: 608-17.

ADDRESSES. Departments of Urology (Prof R. A. Janknegt, MD, E. H J Weil, MD), General Surgery (C. G M. I Baeten, MD), and Clinical Neurophysiology (Prof F Spaans, MD), Academic Hospital Maastricht, Maastricht, Netherlands. Correspondence to Prof R A. Janknegt, Department of Urology, University Hospital Maastricht, PO Box 5800, 6202 AZ Maastricht, Netherlands