Therectovaginalseptumiscarefullydissectedfor3−5cmcephalad, awayfromtheanalverge.

Abluntdissectionismadefromeachendoftheperinealincision laterallyanddorsallytocreateaperianaltunnel.Onceatunnelhasbeen fairlywellestablished,theintroducertoolencirclestheanalcanal, workingthroughtheanococcygealligamentusingopposinghandsto meetthetool,guidedwithafinger.

Toproperlydeterminethedevicesize,thesizingtoolispulledtosnug theanalcanal.

Thenumberonthesizingtoolindicatesthedevicesizeindicatedbelow thelineshownonthetool.A17-beaddevicewasusedonthepatientin thefigures.

Afterchangingglovesandflushingthewoundwithdilutediodine solution,theselectedMASistakenfromthesterilepackageandbrought throughthetunnelwiththeintroducertoolplacedbackintothetunnel. ThesuturesoftheMASaretemporarilytiedtogetherpriortothe fluoroscopycheckingtoensurethatthesizinghasbeenappropriate.A devicewith1–3beadsopenontheX-raysisconsideredsatisfactory, meaningwellappliedtotheanalcanal.Ifnotso,animplantofasmaller sizehastobeplaced.

Thedeviceimmediatelyfunctionswithoutanyinterventionfromthe surgeonorthepatient.Thepatientmayimmediatelyresumearegular diet.Nopost-operativeantibioticsarerequired.Minimalpostoperative painisexpected.Passageofstoolsoonaftertheimplantationisimportant toallowtheconstructionofacapsulearoundtheMASlargeenoughfora completeopeningofthedevice.Therefore,regularpostoperativebowel motionsareencouraged.Laxativesorsuppositoriesmayberequired.

TherapeuticsuccessratesofMASintreatingsevereFIrangedbetween 53%and66%atfollow-upinthelatestpublications.Theinternational feasibilitystudy,startedin2008,reportedon14patientsat6-month follow-upasuccessin80%ofcaseswhenthedevicewasinplaceand 50%whenincluding3patientswhounderwentdeviceexplanation.Ina recentsingle-centerstudyfromGermany,a6-monthtreatmentsuccess rateof76%wasreportedwithaClevelandClinicIncontinenceScore (CCIS)decreasingfrom17.5to7.3pointsandafecalincontinencequality oflifequestionnaireimprovinginallfourdomains.In76%ofthe implantedpatients,boweldiaryresultsshowedagreaterthan50% reductioninthenumberofFIepisodesperweek.Similarmiddle-term resultswereobservedinaFrenchseriesof23patients(Table16-2).

TheMASappearstobeapromisinginnovation,butundoubtedlythereis alearningcurvewiththistechnology,particularlyinpatientselection. Presently,thesignificanceoftheMASinthetreatmentalgorithmofFIis yettobedetermined.Withalimitednumberofpatientstreatedandonly middle-termfollow-upavailable,itisyettobeobservediftheMAScan withstandthetestoftime.Itisourhopethatthedevicewillagainbe madeavailabletothepatientswhomightbenefitfromMASimplantation.