Assessment of peak kilovoltage accuracy in ten selected X-ray ...

Results: The kVp accuracy test for X-ray units D 1 , D 2 , D 5 , D 6 , D 7 , and D 8 were within an acceptable limit of ±5% at all selected tube ...   UsersOnline:329 Home Currentissue Aheadofprint Search Aboutus Editorialboard Archives Submitarticle AuthorGuidelines Subscribe Contacts Login      ORIGINALARTICLE Year:2016 | Volume :3  | Issue:2 | Page:60-65 AssessmentofpeakkilovoltageaccuracyintenselectedX-raycentersinLagosmetropolis,South-WesternNigeria:AqualitycontroltesttodetermineenergyoutputaccuracyofanX-raygenerator MichaelOnoriodeAkpochafor,AkintayoDanielOmojola,KofoworolaOluwatoyinSoyebi,SamuelOlaoluAdeneye,MosesAdebayoAweda,HelenBolanleAjayi DepartmentofRadiationBiology,Radiotherapy,RadiodiagnosisandRadiography,CollegeofMedicine,LagosUniversityTeachingHospital,IdiAraba,Lagos,Nigeria DateofWebPublication17-Jun-2016 CorrespondenceAddress:AkintayoDanielOmojolaDepartmentofRadiationBiology,Radiotherapy,RadiodiagnosisandRadiography,CollegeofMedicine,LagosUniversityTeachingHospital,Idi-Araba,LagosNigeriaSourceofSupport:None,ConflictofInterest:NoneCheckDOI: 10.4103/2394-2010.184231   Abstract Background:MostX-raycentersrecruitedforthisstudyadmittedthattherehavebeennomaintenancechecksontheenergyoutputaccuracyoftheirX-raymachines.Mostcenterscomplainedofrecurrentmachinebreakdownduetopoorpowersupply,whileotherspointedoutthatX-raymachineagecouldbeacontributoryfactortopoorimagequality.AimandObjectives:Todeterminepeakkilovoltage(kVp)accuracyofindividualX-rayunitandtocomparetheirvalueswithrecommendedstandardsandtofurtherestablishifmachineagehasasignificanteffectonmeankVpaccuracy.MaterialsandMethods:OnededicatedconventionalX-rayunitineachofthetendiagnosticcenterswasusedforthisstudydenotedasD1−D10.kVpwasmeasuredusinganoninvasiveUnforsThinXRADkVpmeter.ThekVpaccuracytestwascarriedoutbypositioningtheUnforsThinXRADkVpmeteratthecenterofthebeamaxisofthepatient'scouchatafocustoimagedistanceof100cm.TheX-raymachinetechnicalfactorswerevariedbyselectingtubepotentialwithintherangeof50−120kVpatafixedtubecurrentof20mA.DataanalysisvaluewasdoneusingGraphPadPrismversion5.0statisticssoftware(GraphPadSoftware,Inc.,SanDiego,California,USA).Results:ThekVpaccuracytestforX-rayunitsD1,D2,D5,D6,D7,andD8werewithinanacceptablelimitof±5%atallselectedtubepotentialfrom50to120kVp,X-rayunitsD2andD6showedaccuratecomplianceatmuchlowerkVpaccuracyvalues.X-rayunitsD3andD10wereabove±5%accuracylimitatallselectedkVptubepotential.NostatisticallysignificantdifferencesexistbetweenmachineageandmeankVpaccuracy(P=0.770).Conclusion:One-fourthofthetotalkVpaccuracyresultswereabove±5%limit.OldX-raymachinehadhigherchancesoffailedkVpaccuracy.TracesoffailedtestwerealsonoticedinX-raymachinesbelow5years.Keywords: Milliampereseconds,peakkilovoltage,radiationdose,X-ray Howtocitethisarticle:AkpochaforMO,OmojolaAD,SoyebiKO,AdeneyeSO,AwedaMA,AjayiHB.AssessmentofpeakkilovoltageaccuracyintenselectedX-raycentersinLagosmetropolis,South-WesternNigeria:AqualitycontroltesttodetermineenergyoutputaccuracyofanX-raygenerator.JHealthResRev2016;3:60-5 HowtocitethisURL:AkpochaforMO,OmojolaAD,SoyebiKO,AdeneyeSO,AwedaMA,AjayiHB.AssessmentofpeakkilovoltageaccuracyintenselectedX-raycentersinLagosmetropolis,South-WesternNigeria:AqualitycontroltesttodetermineenergyoutputaccuracyofanX-raygenerator.JHealthResRev[serialonline]2016[cited 2022Jan1];3:60-5.Availablefrom: https://www.jhrr.org/text.asp?2016/3/2/60/184231   Introduction Thepeakkilovoltage(kVp),alsoknownasthemaximumvoltagevalueatanytimeduringexposureisanimportantparameterofanX-raymachine,whichisadirectproductofitsgeneratorcircuitdesignandothercomponents.OtherimportantparametersofanX-raymachinearetubecurrent(milliamperage[mA])andexposuretimer(seconds/milliseconds).ThekVptestprovidesameasurementofthepeakelectricalpotentialacrossthex-raytubewhenitisoperating.[1],[2]ThereareseveralcommonX-raycircuitgeneratordesignsinusetoday.Theyincludethesinglephase,threephase,constantpotentialandmedium/high-frequencyinvertergenerators,theyallusestep-uptransformerstogeneratehighvoltage,stepdowntransformertoenergizethefilamentandrectifiercircuittoensureproperelectricalpolarityattheX-raytube.[3],[4]Indiagnosticradiology,thekVpisoneofthemostimportantparameteraffectingbothradiationexposureandimagecontrast(theamountofdifferencebetweentheblack/whitesontheradiograph).[5]TheX-raykVpismostcritical;asmallerrorofthisvariablewillhaveagreatereffectonthefinalradiographicorfluoroscopicimagethananequivalentvariationinanyoftheotherparameterssuchastubecurrent(mA),exposuretime,andfocustoimagedistance(FID).[6],[7]Itis,however,importanttonotethatselectedexposurefactorssuchasthekVpandmilliampereseconds(mAs)canonlybeaccurateiftheX-raymachineisfunctioningoptimally.FinalaccurateradiographcanbeobtainedwhenappropriatekVpandmAsvaluedareselected,aswellasproperpatientpositioningisobserved,properuseofimageintensifyingscreen,theuseofappropriategridtoreducepatientdosewhereappropriate,theuseofappropriateairgaptechniqueandgoodprocessingdevices(manualprocessing/automaticprocessor/digitalprocessor).Forthisreason,optimizationofexposuresrequiresestablishingqualityassurance(QA)andqualitycontrol(QC)programstoensureoptimumperformanceoftheX-rayequipment."QAprogram"meansanorganizedentitydesignedtoprovide"QA"foradiagnosticradiologyfacility.Thenatureandextentofthisprogramwillvarywiththesizeandtypeofthefacility,thetypeofexaminationsconducted,andotherfactors."QCtechniques"arethosetechniquesusedinthemonitoring(ortesting)andmaintenanceofthecomponentsofanX-raysystem.[8]QCtechniquesthusareconcerneddirectlywiththeequipment.Unfortunately,mostX-raycentersinNigeria,justasitisinmostso-calledthirdworldcountries,stilloperatewithveryold,nearobsoletefacilitiessuchasX-raymachinesandaccessories.Measurestoensureoptimalequipmentperformancesuchasroutinemaintenancechecks,recalibrationoftheelectric,mechanical,anddosimetryperformanceparametersarealmostnonexistent.[9]Inapreviousstudy,itwasreportedthat"thereareover4000X-raymachinesinNigeriawith<5%ofthemunderanyformofregulatorycontrol."[10]InNigeria,theNigerianNuclearRegulatoryAuthority(NNRA)issaddledwiththeresponsibilityofregistering,licensing,inspecting,andenforcingnuclearsafetyandradiologicalprotectioninallpracticeinthecountry.[11]Overtheyears,therehavebeentheproblemsoffeedbacksbetweenregulatorsandendusersintermsofcompliancewithQCprogramsofX-rayfacilitiesinNigeria.Inthisstudy,radiographersthatwererecruitedadmittedthattherehasbeennomaintenancecheckontheenergyoutputoftheirX-raymachines,andtheyalsoreportedrecurrentbreakdownduetopowerfailurewithnoQCchecksafterrepairs.OtherspointedoutthatX-raymachineagecouldbeacontributoryfactortopoorimagequality.ThereasonwhythisstudyfocusedmoreonkVpwastocarryoutaQCkVpaccuracytestontheenergyoutputofX-raygenerator,toencourageenduseroftheneedtocarryoutkVpaccuracytesteachtimerepairworksaredone.ThisstudywasthereforecarriedouttodetermineenergyoutputaccuracyoftenX-raymachinesbyfirstdeterminingthekVpaccuracyofeachX-rayunitandcomparingthemwithestablishedstandardandtofurtherestablishifmachineagehasasignificanteffectonmeankVpaccuracy.  Materialsandmethods Inthisprospectivecross-sectionalstudycarriedoutbetweenAugustandNovember2015,conveniencesimplerandomsamplingtechniquewasusedtoselect10X-raycentersinLagosmetropolisthathavebothmobileandstatic(ceilingmounted)conventionalX-raymachines.BothmobileandstaticX-raymachinevoltagerangewas50−150kVpandquantity(Q=It)whichisaproductofthetubecurrentandexposuretimeinsecondswaswithintherangeof0.2-800mAs[Table1].However,onlyX-raycenterswithatleastonefunctionalX-raymachinewasselected.EightoutofthetenX-raycenterswerediagnosticbasedwhiletwowerehospital-based,havingRadiologyDepartments.Sevenoutof10centersusedmanualandautomaticprocessingdeviceswhilethreecentersuseddigitalprocessingsystems.Table1:X-raymachinetype,manufactureandinstallationdatesClickheretoviewItwasdiscoveredthatfourcentersdidnothaveoperationalandcircuitmanuals.Radiographersreportedthatmanualsweremisplaced,lost,notsupplied,ortakenawaybyserviceengineersafterrepairwork.Physicalinspectionwasusedtoingettingmanufacturedateandinstallationdatesoflostmanuals.TheinvestigationalsoshowedthatmostoftheX-raymachinesthatweretagged"new"wereactuallyrefurbished.Furthermore,onlyradiographerswithatleast2-3yearsjobexperiencewererecruitedintothestudy.RecruitedradiographerswereallregisteredandlicensedtopracticeinthecountrybyRadiographers'RegistrationBoardofNigeriaandtheyallgaveverbalconsenttotakepartinthestudybeforebeingrecruited.AllX-raymachinesforthisstudymetNationalandInternationalCertificationslikeEuropeanConformity,InternationalOrganizationforStandardization,InternationalElectrotechnicalCommission(IEC),GoodManufacturingPractice,andFoodandDrugAdministrationamongothers.AllX-raymachinesusedforthisstudywerecertifiedbyNNRAforuse.AcertifiedmedicalphysicistcarriedoutkVpaccuracytestassessmentineachcenterusingakVpThinXRADdetector(withserialnumber-30001232manufacturedbyUnfors).TheThinXRADdetectorwasconsideredmostappropriateforthisstudybecauseitisasmall,fullyautomatednoninvasiveQCinstrumentthatsimultaneouslymeasuresthedose,doserate,kVp,exposuretime,andpulsesusingdetectors.kVpaccuracytestwascarriedoutbypositioningthekVpThinXRADdetectoratthecenterofthebeamaxesatanFIDof100cm[12][Figure1].Although100cmFIDisaknownandaccepteddistanceusedinmostconventionalradiographystudiesdependingonregionofthebodytobeimaged,theparameterthatwasusedtoarriveat100cmFIDwasfromastudybyWelanderandWickman[13]whointheirworkdeterminedthemeanenergyimpartedintoauniformphantom(mimickedhumansubject).ThepercentagenormalizedenergyimpartagainstFIDshowthatImagereceptor,aregionofinterestandentrancesurfaceofthebeamwasapproximately100cm.IndicatingthattherewouldbegoodpenetrationofX-raybeamthroughthesubjectandlessscattertotheimagereceptor.Thiscanalsobeexplainedbytheairgaptechniquewhichwasmoreeffectiveinreducingscatterat100cmFID.[14]ThekVpaccuracyofeachX-raymachinewasdeterminedbycalculatingtheratioofthedifferencebetweenmeasuredkVpandselectedkVptoselectedkVpmultipliedby100.Themodulussign,whichisalsoknownastheabsolutevalueinEquation1isnormalizedtogiveapositivenumber.ThekVpaccuracywasthereforecalculatedusingtherelation:[15],[16],[17],[18]Figure1:ExperimentalsetupofoneoftheX-rayunitandnoninvasivemeterClickheretoviewWhereXmisthemeasuredvalueofpeaktubekilovoltage(kVp)fromthenoninvasivemeter,andXsisthevalueoftheselectedkilovoltage(kV)fromthecontrolpaneloftheX-raymachine.Theresultsfor%kVpaccuracywerecomparedwithalreadyestablishedperformanceaccuracytestof±5%asrecommendedbytheAmericanAssociationofPhysicistsinMedicinewhoaresaddledwiththeresponsibilityofensuringaccuracy,safety,andqualityintheuseofradiationinmedicalproceduressuchasmedicalimagingandradiationtherapyfacilitiesandIEC61676standardformedicalelectricalequipment-DosimetricinstrumentsusedfornoninvasivemeasurementofX-raytubevoltageindiagnosticradiology.[6],[7],[19]  Results Atotalof10X-rayunitsin10centerswereusedforthisstudy[Table2].Themean±standarddeviationkVpaccuracyforeachunitdenotedasD1−D10wasasfollows:0.94±0.18,0.49±0.63,9.25±4.05,3.31±1.77,3.72±0.73,0.99±0.74,1.54±1.63,1.19±0.65,4.18±1.23,and14.1±3.45,respectively.Table2:Selectedandmeasuredpeakkilovoltageaccuracyfor10X-raycenter(D1-D10)at20mAsClickheretoviewX-raymachineagefrommanufacturedatetoatimewhenthestudywasdoneforeachunitD1toD10rangedfrom2to11years,anditsmeankVpaccuracywasbetween0.49±0.63and14.1±3.45[Table3].Pairedtwo-sidedt-test(unequalvariance)Pvalueat0.05levelswas0.770.Table3:X-raymachineageandmeanpeakkilovoltageaccuracyClickheretoviewThegraph[Figure2]ofoneoftheX-rayunitD2whichpassedthekVpaccuracytestshowsthattheselectedkVpvaluesandmeasuredkVpvalueswerealmostindirectproportion.AstheselectedkVpvalueincreases,themeasuredkVpalsoincreaseswithaslightchange.Inaddition,thegraphoftheX-rayunitD10whichtotallyfailedthekVpaccuracytestshowsthattheselectedkVpandmeasuredkVpvalueswerenotindirectproportion[Figure3].Figure2:SelectedpeakkilovoltageagainstmeasuredpeakkilovoltageforX-rayunitD2ClickheretoviewFigure3:SelectedpeakkilovoltageagainstmeasuredpeakkilovoltageforX-rayunitD10Clickheretoview  Discussion ThekVpaccuracytestforX-rayunitD1,D2,D5,D6,D7,andD8werewithinacceptablelimitof±5%atallselectedtubepotentialfrom50to120kVp[Table2],X-rayunitD4andD9failedthekVptestat50kVpand58kVprespectively,showingthatnotallselectedkVpvaluespassedthetest.TwoX-rayunitsD2andD6showedaccuratecomplianceatmuchlowerkVpaccuracyvalueswiththeirmachineagesbelow5years.Inthisstudy,therewasnostatisticallysignificantdifferencebetweenX-raymachineageandmeankVpaccuracy(P=0.770)usingthepairedt-test.ThisresultwasseentobeconsistentwithastudybyAlirezaetal.[20]whosestudyalsoshowedthattherewasnosignificantdifferencebetweenkVpaccuracyandthemachineage.Alirezaetal.meankVpaccuracywas3.3±5.22,3.86±4.87,and10.87±5.56andmachineagewas≤10,10-20and≥20years,respectively.ItwasalsodiscoveredfromhisstudythatolderX-raymachineshavehighchancesoffailedkVpaccuracy.Thiswasalsoseeninthisstudyformachinesbetweentheagesof10and11years.ThereasonwhytherewasnostatisticaldifferencewasfactthatsomeX-rayunits(D4andD9)whichwerebelow5yearsalsofailedthekVpaccuracytest.IndicatingthatQCprogramisanantidotetocheckmateX-raymachineperformanceirrespectiveoftheageofthemachine.Inthisstudy,atotalof40kVpaccuracyresultswereanalyzed,fromwhich10kVpresultswereabove±5%.Anoverallresultfromthisstudyindicatedthatone-fourth(25%)oftheX-rayunitsfailedthekVpaccuracytest.TwentypercentoffailedkVpwasseeninX-raymachinebetween10and11years.FivepercentoftracesoffailedkVpwerealsoseeninX-raymachinebelow5years.FailedkVpaccuracytestcouldbeattributedtoalightedproblemsbeingfacedbyradiographers(operators)whocomplainedofalackofmaintenancetest,frequentbreakdownwithoutrecalibrationofkVpandmAsafterrepairsandrepeatX-rayexaminations.OneoftheimplicationsoffailedkVpistheproductionoflowerenergyphotons(X-rays),whichinmostcasesareofnodiagnosticpurposetherebyaffectingtheoutcomeoftheradiograph.FailedkVptrendwasseeninasimilarstudybyMehrdadetal.[21]inwhich28kVpaccuracyresultswereanalyzedoutofwhich35%ofthetotalresultfailedthekVpaccuracytest.Furthermore,kVpaccuracywasfoundtobeunsatisfactory(29.5%)inastudyconductedbyAlirezaetal.[20]AgraphofmeasuredkVpandselectedkVp[Figure2]showlinearpropertyofthetubepotentialforX-rayunitD2.ThisproofsthattheKVpsetvalueonthecontrolpanelproducesX-rayswiththealmostsameamountofcomparableandconsistentenergy.ThedeviationwasseenfromthelinegraphinX-rayunitD10,whichwasinconsistent;proofingthattherewasdistortionbetweenthesetkVpvaluesandmeasuredvalues[Figure3].X-rayunitD3withselectedtubepotentialof70,90,110,and120kVphadkVpaccuracyof12.14%,13.33%,5.45%,and6.11%andX-rayunitD10withselectedtubepotentialof60,70,80,and100kVphadkVpaccuracyof17.50%,16.43%,12.29%,and10.17%,respectively.ThekVpaccuracyfortheseX-rayunitswasabove±5%accuracylimits.[6],[7],[19]Thereasonsforthesedeviationscouldbeattributedtolinevoltagesupply(electricalfaults)andX-raymachineagewhichwasseeninoldermachinesbetween10and11years.Althoughmorestudiesneededtobedonewithlargesamplesizetofurtherverifythis.InasimilarstudyconductedbyMehrdadetal.[21]inJune2015,inwhichsevenhospitalswereusedinIran,twooftheoldestX-raymachineswereinstalledin1982and1990.TheirkVpaccuracywere17.94%at60kVp,11.19%at70kVp,12.12%at80kVp,and7.29%at100kVpforthefirstand20.34%at50kVp,8.11%at60kVp,9.91%at70kVp,and14.75%at80kVpforthesecond,showingthattheywereabove±5%accuracylimit.X-rayunitD3andD10failedkVprangewas10.17−17.50%(10-11years).ThesevalueswerewithinthoseofMehrdadetal.[21]whosefailedkVpaccuracyrangewas7.29−20.34%(26-34years).InanotherstudybyGodfreyetal.,[22]kVpaccuracytestwasconductedinfivehospitalsinZaria,KadunaState,North-WesternNigeriain2015.Hisstudyresultshowsthat67%oftheoverallkVpaccuracytestsdoneatselectedtubepotentialof60,70,80,90,and100kVpfailedthekVpaccuracytestwiththehighestfailedkVpaccuracyvalueof51.5%noticedinoneofthehospitals.AlthoughtherewerenorecordsfromhisstudyindicatingtheageoftheX-raymachine.TheresultobtainedfromGodfreyetal.[22]studywasfarhigherthanthemaximumfailedkVpvalue(17.50%)thatwasobtainedinthisstudy.AsimilarfailedkVpaccuracytestwasobservedinastudybyOluwafisoyeetal.[23]withanX-rayunitinLagosSouth-WestNigeriaamongothertestconducted,theselectedtubepotentialwere65,70,75,and80kVpandthemeasuredtubepotentialwere56.78,62.33,68.78,and71.34kVp,respectively.ThefailedkVpaccuracyrangewas8.29%−12.65%.Oluwafisoyeetal.[23]failedrangewaslowercomparedtothisstudy.Agahahadietal.[24]assessedtheimpactofQConradiationdosesreceivedbypatientsundergoingabdomenX-rayexaminationwith10X-rayunitsin10differenthospitals,hisstudyalsorevealsthat3outof10X-rayunitfailedthekVpaccuracytest(30%).Agahahadietal.[24]resultwas5%higherwhencomparedwiththisstudy.InadiagnosticX-rayfacilitiesQCperformancestestconductedin196X-rayunitsin19regionsinTanzaniabySungitaetal.,[25]hisQCresultdemonstrated59%failedkilovoltage(kVp),withalloftheX-raymachinesinstalledbeforetheyear2000(over16years).HisstudyshowedthatkVphadthehighestpercentagefailurecomparedtootherQCtestperformed.Resultsobtainedwere34%higherthanthisstudy.Sungitaetal.[25]furtherprovedthevulnerabilityofusingoldX-raymachine.SomeotherfactorsthatmayhavecontributetofailedkVpaccuracytestcouldbepoorqualityofelectricity(lowcurrent)whichisamajorprobleminNigeria,variationinthelinevoltagesupplyingtheX-raygenerator,faultyhigh-voltagecables,autotransformer/KVpselectioncircuitryandX-raygeneratorage.  Conclusion ThekVpaccuracyoftendiagnosticX-rayunitsin10centersinLagosmetropolishasbeendetermined.Itwasdiscoveredthatone-fourthofthetotalkVpaccuracyresultfailedtomeettheacceptablelimitof±5%.X-raymachinebetween10and11yearsfailedthekVpaccuracytestcontributing20%.TracesoffailedtestwerealsoseeninX-raymachinebelow5years,contributing5%.TherewasnostatisticalsignificantdifferencebetweenmachineageandmeankVpaccuracyforthisstudy.AlthoughhighchancesoffailedkVpwasnoticedinoldermachinesfrom10years.Thisfactmightbeacontributoryfactortopoorimagequality.FurtherstudywithlargesamplesizeneededtobedonetoascertainifkVpofolderX-raymachinewillaffectimagequality.ThereisaneedforproperimplementationofQAtestduringinstallationandcontroltestfromtimetotimeafterinstallationonbothnewandolddiagnosticX-raymachinesincefailedkVpwasnoticedinmachinesbelow5years,thiswillfurtherhelptoreducerepeatedradiograph,hencereductioninrejectedfilmsandreducepatientdose.AcknowledgmentImmensethankstoallX-raycentersusedwithinLagosmetropolisforthisstudyandprofessorAweda(postgraduatecoordinatorofMedicalPhysicsLUTH)forhisfinancialsupportandencouragement.FinancialsupportandsponsorshipNil.ConflictsofinterestTherearenoconflictsofinterest.    References  1.KramerHM,SelbachHJ,IlesWJ.ThepracticalpeakvoltageofdiagnosticX-raygenerators.BrJRadiol1998;71:200-9.       2.BaorongY,KramerHM,SelbachHJ,LangeB.Experimentaldeterminationofpracticalpeakvoltage.BrJRadiol2000;73:641-9.       3.BushbergJT,SeibertJA,LeidholdtEM,BooneJM.TheEssentialPhysicsofMedicalImaging.2nded.Baltimore:LippincottWilliamsandWilkins;2002.p.112-32.       4.DanceDR,ChristofidesS,MaidmentAD,McLeanID,NgKH.DiagnosticRadiologyPhysics:AHandbookforTeachersandStudents.Vienna:IAEA;2014.p.89-114.       5.TranNT,IimotoT,KosakoT.CalibrationofKVpmeterusedinqualitycontroltestsofdiagnosticX-rayunits.RadiatProtDosimetry2012;148:352-7.       6.AmericanAssociationofPhysicistsinMedicine(AAPM).BasicQualityControlinDiagnosticRadiology.AAPMReportNo.4.Madison:MedicalPhysicsPublishing;1977.       7.AmericanAssociationofPhysicistsinMedicine(AAPM).QualityControlinDiagnosticRadiology.AAPMReportNo.74.Madison:MedicalPhysicsPublishing;2002.       8.InternationalAtomicEnergyAgency(IAEA).RadiationProtectionandSafetyofRadiationSource:InternationalBasicSafetyStandards,SeriesNo.GSRPart3,Vienna,Austria:IAEApublications;2014.p.2-85.       9.NgoyeWM,MottoJA,MuhogoraWE.QualitycontrolmeasureinTanzania:Isitdone?JMedImagingRadiatSci2015;46:S23-30.       10.ElegbaSB.RadiationSafetyOfficer(RSO)inDiagnosticandInterventionalRadiology.KeynoteAddress,UniversityofIbadan,Ibadan,Nigeria.Availablefrom:http://www.archive.punchontheweb.com/articl.aspx\.[Lastupdatedon2013Dec11;Lastaccessedon2016Feb16].       11.NigerianNuclearRegulatoryAuthority(NNRA).Nigerianbasicionizingradiationregulations.Lagos,Nigeria:TheFederalGovernmentPress;2003.       12.ChanCT,FungKK.DoseoptimizationinlumbarspineradiographicexaminationbyairgapmethodatCRandDRsystems:Aphantomstudy.JMedImagingRadiatSci2015;46:65-71.       13.WelanderU,WickmanG.Meanenergyimpartedinrelationtothefocustoobjectdistance.ActaRadiolDiagn(Stockh)1978;19:1014-24.       14.PolettiJL,McLeanD.Theeffectofsourcetoimage-receptordistanceoneffectivedoseforsomecommonX-rayprojections.BrJRadiol2005;78:810-5.       15.ShirinShandizM,BahreyniToosiMT,FarsiS,YaghobiK.LocalreferencedoseevaluationinconventionalradiographyexaminationsinIran.JApplClinMedPhys2014;15:4550.       16.RasuliB,Mahmoud-PashazadehA,BirganiMJ,GhorbaniM,NaserpourM,Fatahi-AslJ.QualitycontrolofconventionalradiologydevicesinselectedhospitalsofKhuzestanProvince,Iran.IranJMedPhys2015;12:101-8.       17.RasuliB,Mahmoud-PashazadehA,GhorbaniM,TabariJuybariR,NaserpourM.PatientdosemeasurementincommonmedicalX-rayexaminationsinIran.JApplClinMedPhys2016;17:5860.       18.IsmailHA,AliOA,OmerMA,GarelnabiME,MustafaNS.Evaluationofdiagnosticradiologydepartmentintermofqualitycontrol(QC)ofX-rayunitsatKhartoumstatehospitals.IntJSciRes2015;4:1875-8.       19.InternationalElectrotechnicalCommission.Medicalelectricalequipment-dosimetricinstrumentsusedfornon-invasivemeasurementofX-raytubevoltageindiagnosticradiology(IEC61676).Geneva,Switzerland:IECpublications;2002.       20.AlirezaKK,PeymanH,MiladM,ShahinN.QualitycontrolofradiographyequipmentsinGolestanProvinceofIran.IranJMedPhys2013;10:37-44.       21.MehrdadG,FatanehN,VahidK.TheevaluationofconventionalX-rayexposureparametersincludingtubevoltageandexposuretimeinprivateandgovernmentalhospitalsofLorestanProvince,Iran.IranJMedPhys2015;12:85-92.       22.GodfreyLD,AdeyemoDJ,SadiqU.RadiologicalkVpaccuracy,reproducibilityandconsistenceassessmentofsomehospitalsinZariaenvironsofKadunastate,Nigeria.ArchApplSciRes2015;7:27-31.       23.OluwafisoyePA,OlowookereCJ,JibiriNN,BelloTO,AlausaSK,EfunwoleHO.Qualitycontrolandenvironmentalassessmentofequipmentusedindiagnosticradiology.IntJResRevApplSci2010;3:148-58.       24.AgahahadiB,ZhangZ,ZarehS,SarkarS,TayebiPS.ImpactofqualitycontrolonradiationdosesreceivedbypatientsundergoingabdomenX-rayexaminationintenhospitals.IranJRadiatRes2006;3:177-82.       25.SungitaYY,MdoeSS,MsakiP.DiagnosticX-rayfacilitiesasperqualitycontrolperformancesinTanzania.JApplClinMedPhys2006;7:66-73.           Figures  [Figure1],[Figure2],[Figure3]      Tables  [Table1],[Table2],[Table3] Thisarticlehasbeencitedby 1 ChestX-raysofnewbornsinamedicalfacility:variationbetweentheentranceskindosemeasurementsusingtheindirectanddirectmethodsforclinicaldoseaudit AkintayoDanielOmojola,MichaelOnoriodeAkpochafor,SamuelOlaoluAdeneye,IsiakaOlusolaAkala,AzukaAnthonioAgboje JapaneseJournalofRadiology.2021; [Pubmed] | [DOI] 2 EstimationofdoseandcancerrisktonewbornfromchestX-rayinSouth-SouthNigeria:acallforprotocoloptimization AkintayoDanielOmojola,MichaelOnoriodeAkpochafor,SamuelOlaoluAdeneye,IsiakaOlusolaAkala,AzukaAnthonioAgboje EgyptianJournalofRadiologyandNuclearMedicine.2021;52(1) [Pubmed] | [DOI] 3 PersonnelradiationdoseassessmentusinganoveldosimeterinthedepartmentofradiologyanddentistryinamedicalfacilityinDeltaState,South-SouthNigeria:Ourexperienceinthelast4years AkintayoDanielOmojola,MichaelOnorideAkpochafor,SamuelOlaoluAdeneye,UkemePiusAniekop,MargaretIdongesitAnizor,Mary-AnnEtimEkpo,ChibuzorBedeMadu TheEuropeanResearchJournal.2017; [Pubmed] | [DOI]        Search   SimilarinPUBMED   SearchPubmedforAkpochaforMOOmojolaADSoyebiKOAdeneyeSOAwedaMAAjayiHB   SearchinGoogleScholarforAkpochaforMOOmojolaADSoyebiKOAdeneyeSOAwedaMAAjayiHB RelatedarticlesMilliamperesecondspeakkilovoltageradiationdoseX-ray AccessStatistics EmailAlert* AddtoMyList* *Registrationrequired(free)    Inthis article Abstract Introduction Materialsandme... 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