Sigma-rec Tum Pouch (mainz Pouch Ii)

Mainz pouch II is a well tol er ated form of con ti nent uri nary di ver sion in terms of mor bid-ity, pro tec tion of the up per uri nary tract and con-ti nence rate, even in pa tients aged >65 years. Mainz pouch II was de scribed by Fisch and Hohenfellner in 1991. They viewed the sim plic ity and reproducibility of the op er a tion as one of its ma jor ad van tages. A good con ti nence rates between 93%-100% af ter this pro ce dure has been shown in pre vi ous stud ies. The longer follow up will show whether these high rates of con ti nence can be maintained with increasing age. The Mainz Pouch II serves as a sat is fy ing con ti nent uri nary di ver sion for both sexes in se lected pa tients in terms of qual ity of life. Eval-u a tion of over all qual ity of life in pa tients with Mainz pouch II uri nary der i va tion has given en cour ag ing results. Com pli ance and co op er a tion of the pa tients, together with pre op er a tive tests for anal com pe tence, are man da tory to avoid com pli ca tions. The Mainz group re ported that the over all com pli ca tion rate was low and comparable with other tech niques of con ti-nent uri nary di ver sion. Dur ing the past years mod i fi-ca tions of the orig i nal tech nique have been de scribed. These repre sent an in creas ing in ter est in the procedure. To day, the tech niques of low-pres sure and reservoirs have com pletely re placed clas si cal ureterosigmoi-dostomy. In this re view ar ti cle the main fo cus is aimed at his tory, com pli ca tions, con ti nence and qual ity of life of pa tients with Mainz pouch II. U retrosigmoidostomy was the first form of su pra-vesical continent urinary diversion and en joyed broad pop u lar ity dur ing the first half of the 20th century. A vari a tion of ureterosigmoidostomy was de scribed by Fisch and Hohenfellner in 1991 and up dated in 1996. 1, 2 This op er a tion, which they termed the …

This op er a tion, which they termed the sigma rec tum or the Mainz II pouch, cre ates a low-pres sure rectosigmoid res er voir of in creased ca pac ity.When this res er voir is full, the basal pressure is 24 cm water.The high est peak pressure recorded was 35 cm water.This low pres sure im proved con ti nence and pro tected the upper urinary tract.They viewed the sim plic ity and reproducibility of the op er a tion as one of its ma jor ad van tages. 1,2 e Mainz pouch II gives good re sults in terms of mortal ity, mor bid ity, and con ti nence.It is a rel a tively sim ple and quick pro ce dure, and is as so ci ated with a good quality of life.It is also suit able for the pro spec tive lap aroscopic cystectomy and di ver sion.The main dis ad van tage is ma lig nant trans for ma tion of the ureterointestinal anasto mo sis.Met a bolic ac i do sis is an other lim i ta tion, but this can be suc cess fully treated by oral al ka liz ing ther apy.Care ful pre op er a tive se lec tion and pa tient com pli ance along with me tic u lous fol low-up are of ut most im portance to avoid com pli ca tions and ob tain good func tional re sults.Pro vid ing ex cel lent con ti nence rate and good qual ity of life, it rep re sents an op ti mal ther a peu tic op tion in se lected cases in which orthotopic blad der sub sti tute or other type of con ti nent uri nary di ver sion is not in dicated or ac cept able.
In this re view ar ti cle the main fo cus is aimed at his tory, com pli ca tions, con ti nence and qual ity of life of pa tients with Mainz pouch II.

RE VIEW CRI TE RIA
We searched for orig i nal ar ti cles fo cus ing on sigma -rec tum pouch (Mainz pouch II) in MEDLINE and Pub Med cov er ing all years in da ta base un til April 2014.The search terms we used were "ureterosigmoidostomy", "cystectomy", "com pli ca tions", "con ti nence rates", and "qual ity of life" com bined with "Mainz pouch II".All papers iden ti fied were Eng lish-lan guage full text pa pers.We also searched the ref er ence lists of iden ti fied ar ti cles for fur ther pa pers.e m i z e r

THE HIS TORY OF MAINZ POUCH II
The first uri nary di ver sion us ing the anus con ti nence was pub lished over 150 years ago by Si mon. 3 Nine teenth cen tury was the 'cen tury of uri nary di ver sion'; the ini tial de scrip tion of many tech niques dates back to the pe riod be tween 1890 and 1920.
Pri mary en thu si asm was fol lowed by dis ap point ment when se ri ous prob lems, such as elec tro lyte im bal ance, pyelonephritis, re nal func tion de te ri o ra tion and re nal calculi be came ev i dent.Also, sec ond ary ma lig nan cies arising at the ureteral im plan ta tion site were ob served.However, sec ond ary ma lig nan cies were later also re ported in the other forms of uri nary di ver sion. 4Crit ics of ureterosigmoidostomy tend to quote pub li ca tions deal ing with com pli ca tions in pa tients op er ated on be fore the 1950 s . 5n other ma jor draw back of ureterosigmoidostomy was fre quency and ur gency es pe cially at night. 5 Urodynamic in ves ti ga tions showed that bowel con trac tions with rise in pres sure in the bowel res er voir are re spon si ble for the incon ti nence. 6By in ter rupt ing the cir cu lar con trac tions (antimesenteric open ing of the bowel and "re con fig u ration") a low-pres sure res er voir can be cre ated thus improv ing con ti nence rates and pro tect ing the up per uri nary tract.Im prove ments in sur gi cal tech niques, new in struments/su ture ma te ri als and the avail abil ity of an ti bi ot ics and al ka lin iz ing drugs suc ceeded in tre men dously re ducing com pli ca tions dur ing and af ter sur gery.The era of low pres sure anal res er voirs be gan.
The first at tempt to lower the pres sure in the rectal reser voirs was made by Kock and as so ci ates when they reported a method of diversion to the rectum augmented by an ileal patch in addition to an intussuscepted nipple valve at the colorectal junction and antireflux implantation of the ureters in the ileal patch. 7This procedure had two main draw backs namely com plex ity of the pro cedure in ad di tion to the defunctioning colostomy necessary for it. 8,9 e ports on sim i lar tech niques ei ther augment ing the sigma with ileal or ileocecal seg ments followed. 10,11 vari a tion of ureterosigmoidostomy was de scribed by Fisch and Hohenfellner in 1991 and up dated in 1996. 1,2 tubularization of in tes ti nal seg ments has been dem onstrated to re duce the fre quency and am pli tude of con tractions and al lows the cre ation of a res er voir with the highest ca pac ity for a given length of bowel.3][14][15] This op er a tion, which they termed the sigma rec tum or the Mainz II pouch, cre ates a low-pressure rectosigmoid res er voir of in creased ca pac ity.
The idea was not new, the first de scrip tion dates back to Kocher in 1907. 16As stan dard tech nique for ureteral im plan ta tion the submucosal tun nel is used the same tech nique as for clas si cal ureterosigmoidostomy.However, in di lated or ureters with thick ened walls it is as soci ated with an in creased com pli ca tion rate.For these the tech nique pub lished by Abol-Enein and Ghoneim for   17 It is also ap pli ca ble for the sigma-rec tum pouch. 18Dur ing the past years mod i fi ca tions of the orig inal tech nique have been de scribed. 19 20These rep re sent an in creas ing in ter est in the pro ce dure.To day, the techniques of low-pres sure and res er voirs have com pletely replaced clas si cal ureterosigmoidostomy.

EARLY AND LONG TERM COM PLI CA TIONS OF MAINZ POUCH II
In the past, ureterosigmoidostomy has been strongly crit i cized mainly due to its com pli ca tions.In or der to over come these draw backs, fol low ing Hinnman's prin ciples of detubularization, the Mainz Pouch II tech nique was in tro duced as a sim ple detubularized ureterosigmoidostomy pro ce dure, by Fisch et al. 2,17,21 It has been demon strated that detubularization of bowel seg ments reduces the fre quency and am pli tude of con trac tions and thus re duces the risk of pyelonephritis and re flux of urine in antiperistaltic di rec tion.
The re sults of the Mainz II pouch were re ported by Fisch and col leagues in 1997. 2 Be tween 1990 and 1993, 73 pa tients (59 adults and 14 chil dren) un der went the Mainz II pouch pro ce dure.Early com pli ca tions were encoun tered in 5 of 73 pa tients (6.8%).These in cluded single ex am ples of a dis lodged ureteral stent, pneu mo nia, pul mo nary em bo lism, wound dehiscence, and ileus neces si tat ing sur gi cal in ter ven tion.There were eight (10.9%)late com pli ca tions that re quired sur gery: ureteral ste no sis oc curred in five pa tients (6.8%); one pa tient with nephrolithiasis was treated with extracorporeal shockwave lithotripsy; one pa tient with rup ture of the an te rior su ture line re quired tem po rary co los tomy; and one patient ex pe ri enced perianal bleed ing af ter che mo ther apy that re quired en do scopic co ag u la tion.Six pa tients presented with pyelonephritis (8.2%) and were treated with an ti bi ot ics.The Mainz group con cluded that the over all com pli ca tion rate was low and com pa ra ble with other tech niques of con ti nent uri nary di ver sion.
Hadzi-Djokic at al. 20 re ported early com pli ca tions in 14% of pa tients, and late com pli ca tions in 8% of pa tients un der went the Mainz II pouch pro ce dure.Early com plica tions in cluded pro longed ileus, pyelonephritis, uni lateral ureterohydronephrosis, bi lat eral ureterohydronephrosis, and in cip i ent re nal fail ure.The late com pli ca tions in -cluded: uni lat eral ureteric im plan ta tion site ste no sis, bilat eral ureteric im plan ta tion site ste no sis, and ven tral hernia.The most im por tant com pli ca tions were ureteric implan ta tion site ste no sis in 14 RUs (4%).Ste no sis can occur at any time up to 2 years af ter ureteric im plan ta tion into the rectosigmoid us ing the Camey-Le Duc technique, which was used in this study. 24If submucosal tunnel is per formed, ste no sis pre dom i nantly oc curs dur ing the first two years af ter sur gery. 20Some au thors con sider that those stenotic com pli ca tions are not suit able for balloon di la ta tion or cold knife in ci sion, in con trast to early stenotic com pli ca tion. 23,25 e dif fer ent ureteric im plan ta tion meth ods did not seem to be im por tant.Ureteric im plan ta tion into the false seg ment of the sig moid co lon may cause ureteric kink ing and up per uri nary tract ob struc tion. 26When up per uri nary tract di la ta tion sec ond ary to uretero-colic stric ture becomes ev i dent early af ter sur gery, bal loon di la ta tion or cold-knife in ci sion may be a sufWcient op tion. 27,28 f scar ring and Wbrosis have started, ureteric neo-im plan tation is in ev i ta ble. 29e gard ing sec ond ary ma lig nan cies de vel op ment, it has been most fre quently as so ci ated with ureterosigmoidostomy. 30 The risk has not been changed by nu mer ous mod i fi ca tion of ureterosigmoidostomy, in clud ing Mainz Pouch II pro ce dure.Since it has been re ported from large se ries that mean la tent pe riod for ma lig nant trans for mation is 26 years, de vel op ment of sec ond ary ma lig nan cies is es pe cially im por tant in pa tients with long life ex pectancy. 15,31,32The in ci dence of co lon car ci noma is im portant in pa tients with a long life-ex pec tancy but may not be sig nif i cant in el derly pa tients who re quire cystectomy for ma lig nant dis ease.An nual sigmoidoscopy 5 years after a Mainz Pouch II pro ce dure can help to screen for sec ond ary ma lig nancy.
Bas tian et al. 19 con sider that pyelonephritis af ter Mainz Pouch II pro ce dure is to be more fre quent among younger pa tients, sug gest ing that there is good pro tec tion of the up per uri nary tract in el derly pa tients.Gen er ally, reported in ci dence of this com pli ca tion from a large se ries sug gests that low pres sure res er voir, straight ureteral path by its fix a tion to the prom on tory in Mainz Pouch II proce dure pro vides up per uri nary tract pro tec tion as good as other uri nary di ver sions. 8,12,15,22,23.1 2][33] Al though urine stor age lasts lon ger in sigmoidorectal pouch then in clas sic ureterosigmoidostomy, avail able sur face for the re sorp tion of ions is smaller. 21et a bolic com pli ca tions re lated to hyperchloraemic ac ido sis could be pre vented by cor rect ing the acid-base balance with al ka liz ing agents; about 60% of pa tients needed oral med i ca tion af ter the Mainz pouch II pro cedure. 2,15,34Com pli ca tion rates af ter clas sic ureterosigmoidostomy were up to 80%. 34,35

CON TI NENCE IN PA TIENTS WITH MAINZ POUCH II
The Mainz Pouch II pro ce dure pro vides a low pres sure, high ca pac ity res er voir, which pre vents overdistension of the co lon and con se quent stim u la tion of mo til ity and evac u a tion of the con tent. 21,29,36A good con ti nence rates be tween 93%-100% af ter this pro ce dure has been reported by sev eral au thors (Ta ble 1).It has been dem onstrated that clas sic ureterosigmoidostomy is as so ci ated with bowel fre quency and urge in con ti nence, with night-time in con ti nence in more than 50% and day-time in con ti nence 7%.How ever, the sphincter com pe tency decreases with in creas ing age. 24isch et al. 2 re ported day time con ti nence in 94.5% of pa tients and night time con ti nence in 98.6% of pa tients un der went the Mainz II pouch pro ce dure.Wood house and Christofides 36 re ported on their ex pe ri ence with the Mainz II pouch in 15 pri mary cystectomy pa tients and 4 pa tients with prior stan dard ureterosigmoidostomy who were in con ti nent.They re ported ex cel lent re sults: 14 of 15 (93.3%) of the pri mary pa tients achieved doc u mented day time and night time uri nary con trol, while the re maining pa tient re fused fol low-up but re ported con ti nence.The four pa tients un der go ing a sal vage pro ce dure fared less well.Only two pa tients be came con ti nent, while the re main ing two were found to be in chronic re ten tion.Their failed con ti nence was be lieved to be sec ond ary to in ad e quate pouch emp ty ing.Sim i larly, ex cel lent re sults have been achieved by Atta et al. 12 They re ported full day time and night time uri nary con ti nence in 15 of 15 patients and no ma jor post op er a tive com pli ca tions.Hadzi-Djokic et al. 20 in their study of 220 pa tients with Mainz pouch II re ported only three pa tients with in con tinence.Two of three in con ti nent pa tients had an ex plo ration and con ver sion into an ileal con duit di ver sion, and the third had a con ver sion into a cu ta ne ous di ver sion.
There is a lack of clear con sen sus re lated to pre op er ative rectodynamic eval u a tion.Fisch et al. 29 sug gests it as rou tine pre op er a tive eval u a tion.Bas tian et al. 19 re ported that these eval u a tion should be per formed in high risk patients for in con ti nence.

QUAL ITY OF LIFE IN PA TIENTS UN DER GO ING MAINZ POUCH II URI NARY DI VER SION
The im pact of dis ease and treat ment on the pa tient's over all well-be ing and func tion ing is a topic of ris ing inter est in clin i cal re search.Re search ers have found that the type of uri nary di ver sion does not seem to be as so ciated with dif fer ences in the qual ity of life. 39,40 th ers have shown that con ti nent di ver sion is ad van ta geous over in con ti nent di ver sion. 8,41,42 Tay, can cer treat ment no lon ger im plies only the cure and con trol of the dis ease.The ef fect on psy cho log ical, func tional, so cial and eco nomic life of the pa tient plays a more im por tant role dur ing de ci sion in re spect to the type of uri nary di ver sion.How ever, once a method of uri nary di ver sion is se lected, the pa tient has a strong tendency to want to be lieve that he has made the cor rect choice.
Bas tian and col leagues have re ported on the health related qual ity of life in 83 pa tients un der go ing Mainz II uri nary di ver sion.They found that qual ity of life was sim i lar to that of age-matched con trols ex cept for di arrhea symp toms, with 100% day time con ti nence. 19he Mainz Pouch II serves as a sat is fy ing con ti nent urinary di ver sion for both sexes in se lected pa tients in terms of qual ity of life.In terms of con ti nence mod i fied ureterosigmoidostomy can lead to day time con ti nence rate of 100%.Eval u a tion of over all qual ity of life in patients with Mainz pouch II uri nary der i va tion in the previ ous stud ies is shown in Ta ble 2.
It is al most im pos si ble to com pare the stud ies of postop er a tive health re lated qual ity of life since there is no con sen sus on what should be mea sured and many dif ferent test in stru ments are used.To min i mize the dif ferences in health re lated qual ity of life af ter uri nary di version the pa tient should be part of the de ci sion mak ing and all op tions of di ver sion should be dis cussed.