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Effectiveness of prolonged hydrostatic dilatation of bladder
EFFECTIVENESS DILATATION
OF PROLONGED
HYDROSTATIC
OF BLADDER
FREDRICK
N. WOLK,
MICHAEL
C. BISHOP,
?cl.D. F.R.C.S.
From the Department of Urology, Hills Road, Cambridge, England
Addenbrooke’s
Hospital,
ABSTRACT - Thirty-three patients with intractable frequency and 9 patients with hernaturia from irradiation cystitis, bladder tumors, or both underwent 54 prolonged hydrostatic dilatations of the bladder. Thirty-eight per cent of patients with .frcwencu had low-lasting irnurooement, and 19 per cent had temptn-ary relief. Eight patimts in this group had multiple procedttres, hating imu>ith heinaturia had upprec*iable proced tempwarily after previous treatments. Sir of the 9 @ents palliatice relief. ”
In the late 1960s and early 1970s HelmsteinlV2 described hydrostatic distention of the bladder as a treatment for bladder cancer. Dunn, Smith, and Ardran3 adapted the procedure as a treatwith ment for urgency and urge incontinence favorable results. Holstein et al. ,a Hammonds, \%7illiams, and Mills,j and more recently, Schiff and McGuire’ used the technique to treat radiation-induced hemorrhagic cystitis, bleeding from bladder tumors, and other conditions, with some success. In this article we report our experience with the Helmstein procedure in the treatment of intractable frequency and of bleeding due to malignant disease or radiotherapy. ;Claterial and Methods 1976, and April, 1980, 42 Between January, patients underwent 54 separate Helmstein procedures. The patients were divided into two groups: Group 1 consisted of patients with se\.ere urinary urgency, frequency, and urge incontinence hitherto refractory to conservative medical treatment. Thirty-three patients in this group underwent 44 Helmstein procedures. Two patients were lost to follow-up. All patients had persistent symptoms without infection or obstruction. There were 27 females and 6 males whose ages ranged from follrteen to eight), years (mean fifty-two years).
\
I
Li
,
The response to treatment was graded as follows: Excellent - Resolution of all symptoms. Good - Substantial resolution of most symptoms. Fair -Temporary substantial improvement followed by relapse of all svmptoms. No response - No improvement in symptams.
Eight patients who had had a fair response were offered a second, third, or even fourth procedure. The length of follow-up ranged from four to thirty-five months, with a mean of eighteen months. Group 2 comprised 9 patients with prolonged hematuria due to hemorrhagic radiation q.stitis, bladder tumor, or both. Each patient required multiple transfusions, and the hematuria was refractors to endoscopic and other conservative measures. Neither internal iliac artery ligation, embolization, nor fi)rmalin instillation was used. The mean age of Group 2 patients was seventyseven years, with a rangr of fifty-se\,en to eighty-five years. Three females and 6 males underwent ten procedures. Only 1 patir,nt in this group had a second procedure. Technique The procedure was clone in all patients under continuous epidural anesthesia to a Ie\,el of the
tkiined kit ;tpproxirn:itel! 2.5 IIIIII Fig ;~hok.~ dixtolic hloocl pressure mid c,c*rtainly l)elow~ c s)rstolic pressure. The blood l)I‘~.~ssIIrt’ \\“lS IneasIIred either 1)) ;I sl,h~,rTIlIoIIl~lnotIIeter or hiintra-uteriul cannula. Thrl dIIratioI1 of’ the distention ranged from two to six hmi3, with ;t I II ptients Inean of’ three md one-h:ilf‘ hoIIrs with hematiiria the proc~edIire w’ds generall~~ done for six hours. For ptient\ with IIrgenc! the dIIration of’ the initi:tl procedIIrr> wx two hours. Eight of’ 33 ptients (24 per cxbnt with ill1 d urgency had more than one distc~iition. f01 subsec~iient procedures wert~’ ~.~ontinIIed longer periods.
ti)llrth thorac:ic \,t>rtebra which abolished sensation aiid hIkidder contractions due to stretdlwfles~s. (:ystoscopj~ was performed indrid md tlIf> hladder left empty. One of three t>p3 of‘ lx~lloon c;tthet(sr vies used xvording to availahilit\ T\vo of‘ these catheters were speciall~~ tlesig;ltd fi)l- \~ladcler distention (Fig. 1). l,llt distentioI1 was a&e\-ed 1)). inflation i II 1 pttieilt of ;t condo~Il tied to the end of’s Fole\~ catheter. The catheter w;is attnched to ii Y-connector. to ;i transducei thrJ viitl of \rhich w3s connected kind mriltichannel recorder for cvntiiiuolis monitoring of I)lacider pressure. The other end uxs c~onnected to iIii infusion set Lvith normal saline colorctl \\,itll a f&f, drops of’ methylrne blue. The infiIsim set had no hall valve in the drip c~haiIiI)(~~~ so thut slidden increases iii intra\ c5icxl pr(xt~rt~ ~‘;iused by coughing or moving could I)e trxismittecl hack to the infiision hag of dine Tire pres$IIre in the halloon wxs main-
‘Table 1 suinmarizes the r_rspoI~st~ to treatment. The results are eupresst.d ;l\ thus fin4 result in those ptients who III3deI3vent niorc’ Of‘ ttie 13 ~410 are ~liown than one procedure. 10 had only one procedure. to have no response, Ten of’31 patients who could he %Jowed III> had e?ccellent I-esults. and 2 had ~rIII)stantial impro\~eInent. (Thirty-eight per cent had exc,ellent (19 or good response.) An adclitional 6 patients per cent) had teinporary sIIbstantia1 relief lasting from kvo to twentv-four InontlIs n~e;in seven months). An analysis of’ the 19 procedures in h: patients in Group 1 who had Inul!iple procedures is shown in Figure 2. Six of the p:itit’rlts had two 1 procedIIrea. 1 had three procedurt~s. md had f;xIr.
Table II summarizes in the 9 ptients. In
TABLE: 1 Niimlwr Patients
01’ E:scdltmt
Good
2 0 0 0
0 2
ttie reslilts ot treatment 6 there \\-;;I< ~Iihstantial
1st
Procedures 2nd 3 rd
4th Excellent response to 2nd treatment
Excellent response to 2nd treatment
Refused further
KEY /
Excellent
0-o
Fair
‘\,
No response
t4
FIGURE
2.
I
TABLE II. Response
No response to 2nd treatment
I
Results in patients
Rx
undergoing
multiple
procedures.
to dilatation in patients With hemuturia
Origin of Hematuria
Result
Age
Sex
85
F
Radiotherapy and recurrent invasive tumor
Light hematuria
85
F
Radiotherapy and recurrent invasive tumor
Second procedure done 8 months after first when patient was admitted with 18-hour history of severe bleeding. Second procedure resulted in clear urine until death 6 months later with extensive metastases.
78
M
Could not stop bleeding at time of resection of large tumor at left ureteric orifice
No recurrent bleeding. Patient received post-Helmstein for invasive carcinoma.
84
M
Widespread invasive bladder carcinoma; previous palliative radiotherapy
No recurrent bleeding months later.
73
M
Radiotherapy
Technical failure of balloon. later for hematuria.
79
M
Radiotherapy tumor
and recurrent
Heavy hematuria continued. Patient had palliative cystectomy and diversion 2 months later. He died of pneumonia 3 months after procedure. There was also widespread metastases.
88
M
Radiotherapy tumor
and recurrent
No bleeding for 4 months at which time the patient underwent radiation therapy for recurrent tumor and hematuria. He died 8% months after procedure with widespread metastatic carcinoma.
57
F
Radiotherapy tumor
and recurrent
Heavy hematuria continued until death static carcinoma 2 weeks later.
75
M
Radiotherapy
76
F
Radiotherapy tumor
574
for 5 days then none for eight months.
for 2 months.
Patient
radiotherapy
Died
of pneumonia
had total cystectomy
No hematuria clots easi!y tumor.
2%
10 days
with widespread
No hematuria for 2 months at which time hematuria palliative cystectomy was performed. and recurrent
3 weeks
recurred
metaand
for 3 months followed by light hematuria without controlled by transurethral resection of bladder
UROLOGY
/ DECEMBER
1981
i
VOLUME
XVIII. NUMBER
6
benefit with cessation of bleeding for a minimum of two months. In 2 patients there was no benefit, and in 1 patient in whom a condom was tied to a Foley catheter, the balloon leaked. This was deemed a technical failure. Complications There was one bladder rupture which occurred late in the procedure and was recognized by sudden loss of bladder pressure. The procedure was abandoned immediately and the patient’s bladder drained for one week with a urethral catheter only. A cystogram at the end of this time showed no extravasation. This patient who previously had suffered from intractable urgency and urge incontinence recovered with an excellent result and remains asymptomatic after two years. There were 3 cases of postoperative retention. Two cases resolved spontaneously after a few days of catheter drainage, but in the third patient it was much more difficult to initiate spontaneous micturition. A period of self-catheterization and suprapubic cystotomy were needed. However the patient is now well with minimal symptoms of her original urgency. Mild hematuria was noted in 2 patients in Group 1; in 1 patient it resolved after two days of catheter drainage and in the other it resolved spontaneously. In 2 patients the balloon burst. In 1 patient it occurred at the end of the procedure, and a cystoscopy was needed to recover a missing piece of balloon. In the other patient the first balloon burst after twenty minutes of distention, and the second balloon burst immediately on its introduction into the bladder. A third catheter was inserted safely and the procedure continued without complications. There was no case of renal failure in our group. The only patient who was worse after the procedure was a forty-six-year-old woman with a normal cystometrogram but with severe symptoms of urgency. Comment In patients with severe urge incontinence from an unstable bladder and in whom medical management has failed, a Helmstein procedure can be helpfill. In the present series 38 per cent of the patients showed improvement and an additional 19 per cent had temporary relief. In 40 per cent there was no relief of the urgency or frequency. Our results are similar to those of Ramsden et ul. 7 The morbidity of the procedure is 101~. Bladder rupture occurred in 1 of om
vRoLo(;\’
_I DE(:EZIBER
1981
!
\‘OLL’TSlE ST-111. NVMBER
patients and 2 in the series of Ralnlsden ct al. ,i and, interestingly, all 3 patients h.ad substantial relief of their symptoms. We have tried to analyze the factors that may be responsible for the success or failure of this treatment and ha\,e c:onsidered the length of the procedure, the pressure rise, and the increment of bladder capacity, but none of these appeared to correlate well with the success rate. Eight of the Group 1 patients had multiple procedures. Patients were more likely to benefit from a second or subsequent procedure if their improvement was sustained fc~r a period of longer than four months from their previous procedure. In general, the longer the initial response, the greater the subsequent benefit. Similarly, patients with intractable hematuria did not always respond to hydrostatic dilatation of the bladder. Six of the 9 patients in this group received some temporary palliation. Even if the response was only temporary, the procedure provided a significant improvement in the quality of life for cancer patients who were terminally ill or suffering the eflects of radiation cystitis. So, while the Helmstein procedure is not the panacea for which we had originally hoped, it certainly offers relief to a large number of patients who might otherwise be exposed to a more drastic surgical intervention. A few patients who obtain temporary relief from the procedure may benefit from a subsequent procedure. Universi tv of California Irvine Nedical Center 0range. Ca.lifornia 92717 (DR. WOLK) Reference 1. Helmstein K: Hydrostatic pressure therapy. A new approach to the treatment of carcinoma of the bladder, ()lmscrd~~ Medica [Stock) 9: 32X (1966). of hladder carcinoma I,\ hydrostatic 2. IDEM: Treatment pressure technique, Br. J. Ural. 44: 4.?4 (1972). 3. Dunn M. Smith IC. and Ardran 61.1: Prolonred bladder distention as a treatment of urgent! and 11ree incktinence of Ilrine, ibid. 46: 645 (1974). 4. Holstein P, Jacohsm K. Ptbdersen JF and Sorensen JS: Intravesical hydrostatic pressure treatment: a ne\v method for control of hlevding from the bladder muvow J Ural 44: 4.34 (1973). 5. Hanrmonds JC, \I’illiams JL.. and Mills VI: The control of severe bleeding from the bladder h! intra es~cal hyperbaric therapy. Br. J. Crol. 46: 309 (19741. 6. Schiff‘ hl. and McGuire E: Experience ‘with intravesical Surq. Gynwc~l. Ohstet. 15: 322 hydrostatic pressure balloon. (19301. 7. Ramsden
PP, Smith JC, Dunn hl. and Ardran (Ghf. Distention therap! for unstable hladder. Late resldts including an assessment of I-epcat distentions, Br. J. rrol. 48: 623 (1976)
fi
-_5 ,5
OF PROLONGED
HYDROSTATIC
OF BLADDER
FREDRICK
N. WOLK,
MICHAEL
C. BISHOP,
?cl.D. F.R.C.S.
From the Department of Urology, Hills Road, Cambridge, England
Addenbrooke’s
Hospital,
ABSTRACT - Thirty-three patients with intractable frequency and 9 patients with hernaturia from irradiation cystitis, bladder tumors, or both underwent 54 prolonged hydrostatic dilatations of the bladder. Thirty-eight per cent of patients with .frcwencu had low-lasting irnurooement, and 19 per cent had temptn-ary relief. Eight patimts in this group had multiple procedttres, hating imu>ith heinaturia had upprec*iable proced tempwarily after previous treatments. Sir of the 9 @ents palliatice relief. ”
In the late 1960s and early 1970s HelmsteinlV2 described hydrostatic distention of the bladder as a treatment for bladder cancer. Dunn, Smith, and Ardran3 adapted the procedure as a treatwith ment for urgency and urge incontinence favorable results. Holstein et al. ,a Hammonds, \%7illiams, and Mills,j and more recently, Schiff and McGuire’ used the technique to treat radiation-induced hemorrhagic cystitis, bleeding from bladder tumors, and other conditions, with some success. In this article we report our experience with the Helmstein procedure in the treatment of intractable frequency and of bleeding due to malignant disease or radiotherapy. ;Claterial and Methods 1976, and April, 1980, 42 Between January, patients underwent 54 separate Helmstein procedures. The patients were divided into two groups: Group 1 consisted of patients with se\.ere urinary urgency, frequency, and urge incontinence hitherto refractory to conservative medical treatment. Thirty-three patients in this group underwent 44 Helmstein procedures. Two patients were lost to follow-up. All patients had persistent symptoms without infection or obstruction. There were 27 females and 6 males whose ages ranged from follrteen to eight), years (mean fifty-two years).
\
I
Li
,
The response to treatment was graded as follows: Excellent - Resolution of all symptoms. Good - Substantial resolution of most symptoms. Fair -Temporary substantial improvement followed by relapse of all svmptoms. No response - No improvement in symptams.
Eight patients who had had a fair response were offered a second, third, or even fourth procedure. The length of follow-up ranged from four to thirty-five months, with a mean of eighteen months. Group 2 comprised 9 patients with prolonged hematuria due to hemorrhagic radiation q.stitis, bladder tumor, or both. Each patient required multiple transfusions, and the hematuria was refractors to endoscopic and other conservative measures. Neither internal iliac artery ligation, embolization, nor fi)rmalin instillation was used. The mean age of Group 2 patients was seventyseven years, with a rangr of fifty-se\,en to eighty-five years. Three females and 6 males underwent ten procedures. Only 1 patir,nt in this group had a second procedure. Technique The procedure was clone in all patients under continuous epidural anesthesia to a Ie\,el of the
tkiined kit ;tpproxirn:itel! 2.5 IIIIII Fig ;~hok.~ dixtolic hloocl pressure mid c,c*rtainly l)elow~ c s)rstolic pressure. The blood l)I‘~.~ssIIrt’ \\“lS IneasIIred either 1)) ;I sl,h~,rTIlIoIIl~lnotIIeter or hiintra-uteriul cannula. Thrl dIIratioI1 of’ the distention ranged from two to six hmi3, with ;t I II ptients Inean of’ three md one-h:ilf‘ hoIIrs with hematiiria the proc~edIire w’ds generall~~ done for six hours. For ptient\ with IIrgenc! the dIIration of’ the initi:tl procedIIrr> wx two hours. Eight of’ 33 ptients (24 per cxbnt with ill1 d urgency had more than one distc~iition. f01 subsec~iient procedures wert~’ ~.~ontinIIed longer periods.
ti)llrth thorac:ic \,t>rtebra which abolished sensation aiid hIkidder contractions due to stretdlwfles~s. (:ystoscopj~ was performed indrid md tlIf> hladder left empty. One of three t>p3 of‘ lx~lloon c;tthet(sr vies used xvording to availahilit\ T\vo of‘ these catheters were speciall~~ tlesig;ltd fi)l- \~ladcler distention (Fig. 1). l,llt distentioI1 was a&e\-ed 1)). inflation i II 1 pttieilt of ;t condo~Il tied to the end of’s Fole\~ catheter. The catheter w;is attnched to ii Y-connector. to ;i transducei thrJ viitl of \rhich w3s connected kind mriltichannel recorder for cvntiiiuolis monitoring of I)lacider pressure. The other end uxs c~onnected to iIii infusion set Lvith normal saline colorctl \\,itll a f&f, drops of’ methylrne blue. The infiIsim set had no hall valve in the drip c~haiIiI)(~~~ so thut slidden increases iii intra\ c5icxl pr(xt~rt~ ~‘;iused by coughing or moving could I)e trxismittecl hack to the infiision hag of dine Tire pres$IIre in the halloon wxs main-
‘Table 1 suinmarizes the r_rspoI~st~ to treatment. The results are eupresst.d ;l\ thus fin4 result in those ptients who III3deI3vent niorc’ Of‘ ttie 13 ~410 are ~liown than one procedure. 10 had only one procedure. to have no response, Ten of’31 patients who could he %Jowed III> had e?ccellent I-esults. and 2 had ~rIII)stantial impro\~eInent. (Thirty-eight per cent had exc,ellent (19 or good response.) An adclitional 6 patients per cent) had teinporary sIIbstantia1 relief lasting from kvo to twentv-four InontlIs n~e;in seven months). An analysis of’ the 19 procedures in h: patients in Group 1 who had Inul!iple procedures is shown in Figure 2. Six of the p:itit’rlts had two 1 procedIIrea. 1 had three procedurt~s. md had f;xIr.
Table II summarizes in the 9 ptients. In
TABLE: 1 Niimlwr Patients
01’ E:scdltmt
Good
2 0 0 0
0 2
ttie reslilts ot treatment 6 there \\-;;I< ~Iihstantial
1st
Procedures 2nd 3 rd
4th Excellent response to 2nd treatment
Excellent response to 2nd treatment
Refused further
KEY /
Excellent
0-o
Fair
‘\,
No response
t4
FIGURE
2.
I
TABLE II. Response
No response to 2nd treatment
I
Results in patients
Rx
undergoing
multiple
procedures.
to dilatation in patients With hemuturia
Origin of Hematuria
Result
Age
Sex
85
F
Radiotherapy and recurrent invasive tumor
Light hematuria
85
F
Radiotherapy and recurrent invasive tumor
Second procedure done 8 months after first when patient was admitted with 18-hour history of severe bleeding. Second procedure resulted in clear urine until death 6 months later with extensive metastases.
78
M
Could not stop bleeding at time of resection of large tumor at left ureteric orifice
No recurrent bleeding. Patient received post-Helmstein for invasive carcinoma.
84
M
Widespread invasive bladder carcinoma; previous palliative radiotherapy
No recurrent bleeding months later.
73
M
Radiotherapy
Technical failure of balloon. later for hematuria.
79
M
Radiotherapy tumor
and recurrent
Heavy hematuria continued. Patient had palliative cystectomy and diversion 2 months later. He died of pneumonia 3 months after procedure. There was also widespread metastases.
88
M
Radiotherapy tumor
and recurrent
No bleeding for 4 months at which time the patient underwent radiation therapy for recurrent tumor and hematuria. He died 8% months after procedure with widespread metastatic carcinoma.
57
F
Radiotherapy tumor
and recurrent
Heavy hematuria continued until death static carcinoma 2 weeks later.
75
M
Radiotherapy
76
F
Radiotherapy tumor
574
for 5 days then none for eight months.
for 2 months.
Patient
radiotherapy
Died
of pneumonia
had total cystectomy
No hematuria clots easi!y tumor.
2%
10 days
with widespread
No hematuria for 2 months at which time hematuria palliative cystectomy was performed. and recurrent
3 weeks
recurred
metaand
for 3 months followed by light hematuria without controlled by transurethral resection of bladder
UROLOGY
/ DECEMBER
1981
i
VOLUME
XVIII. NUMBER
6
benefit with cessation of bleeding for a minimum of two months. In 2 patients there was no benefit, and in 1 patient in whom a condom was tied to a Foley catheter, the balloon leaked. This was deemed a technical failure. Complications There was one bladder rupture which occurred late in the procedure and was recognized by sudden loss of bladder pressure. The procedure was abandoned immediately and the patient’s bladder drained for one week with a urethral catheter only. A cystogram at the end of this time showed no extravasation. This patient who previously had suffered from intractable urgency and urge incontinence recovered with an excellent result and remains asymptomatic after two years. There were 3 cases of postoperative retention. Two cases resolved spontaneously after a few days of catheter drainage, but in the third patient it was much more difficult to initiate spontaneous micturition. A period of self-catheterization and suprapubic cystotomy were needed. However the patient is now well with minimal symptoms of her original urgency. Mild hematuria was noted in 2 patients in Group 1; in 1 patient it resolved after two days of catheter drainage and in the other it resolved spontaneously. In 2 patients the balloon burst. In 1 patient it occurred at the end of the procedure, and a cystoscopy was needed to recover a missing piece of balloon. In the other patient the first balloon burst after twenty minutes of distention, and the second balloon burst immediately on its introduction into the bladder. A third catheter was inserted safely and the procedure continued without complications. There was no case of renal failure in our group. The only patient who was worse after the procedure was a forty-six-year-old woman with a normal cystometrogram but with severe symptoms of urgency. Comment In patients with severe urge incontinence from an unstable bladder and in whom medical management has failed, a Helmstein procedure can be helpfill. In the present series 38 per cent of the patients showed improvement and an additional 19 per cent had temporary relief. In 40 per cent there was no relief of the urgency or frequency. Our results are similar to those of Ramsden et ul. 7 The morbidity of the procedure is 101~. Bladder rupture occurred in 1 of om
vRoLo(;\’
_I DE(:EZIBER
1981
!
\‘OLL’TSlE ST-111. NVMBER
patients and 2 in the series of Ralnlsden ct al. ,i and, interestingly, all 3 patients h.ad substantial relief of their symptoms. We have tried to analyze the factors that may be responsible for the success or failure of this treatment and ha\,e c:onsidered the length of the procedure, the pressure rise, and the increment of bladder capacity, but none of these appeared to correlate well with the success rate. Eight of the Group 1 patients had multiple procedures. Patients were more likely to benefit from a second or subsequent procedure if their improvement was sustained fc~r a period of longer than four months from their previous procedure. In general, the longer the initial response, the greater the subsequent benefit. Similarly, patients with intractable hematuria did not always respond to hydrostatic dilatation of the bladder. Six of the 9 patients in this group received some temporary palliation. Even if the response was only temporary, the procedure provided a significant improvement in the quality of life for cancer patients who were terminally ill or suffering the eflects of radiation cystitis. So, while the Helmstein procedure is not the panacea for which we had originally hoped, it certainly offers relief to a large number of patients who might otherwise be exposed to a more drastic surgical intervention. A few patients who obtain temporary relief from the procedure may benefit from a subsequent procedure. Universi tv of California Irvine Nedical Center 0range. Ca.lifornia 92717 (DR. WOLK) Reference 1. Helmstein K: Hydrostatic pressure therapy. A new approach to the treatment of carcinoma of the bladder, ()lmscrd~~ Medica [Stock) 9: 32X (1966). of hladder carcinoma I,\ hydrostatic 2. IDEM: Treatment pressure technique, Br. J. Ural. 44: 4.?4 (1972). 3. Dunn M. Smith IC. and Ardran 61.1: Prolonred bladder distention as a treatment of urgent! and 11ree incktinence of Ilrine, ibid. 46: 645 (1974). 4. Holstein P, Jacohsm K. Ptbdersen JF and Sorensen JS: Intravesical hydrostatic pressure treatment: a ne\v method for control of hlevding from the bladder muvow J Ural 44: 4.34 (1973). 5. Hanrmonds JC, \I’illiams JL.. and Mills VI: The control of severe bleeding from the bladder h! intra es~cal hyperbaric therapy. Br. J. Crol. 46: 309 (19741. 6. Schiff‘ hl. and McGuire E: Experience ‘with intravesical Surq. Gynwc~l. Ohstet. 15: 322 hydrostatic pressure balloon. (19301. 7. Ramsden
PP, Smith JC, Dunn hl. and Ardran (Ghf. Distention therap! for unstable hladder. Late resldts including an assessment of I-epcat distentions, Br. J. rrol. 48: 623 (1976)
fi
-_5 ,5