Con iden iali y S a us: PU - Public, ully open ( emembe o deposi public deli e ables in a us ed eposi o y)
Deli e able Co e Shee
Funded by he Eu opean Union. Views and opinions exp essed a e
howe e hose o he au ho (s) only and do no necessa ily e lec hose
o he Eu opean Union o EURAMET. Nei he he Eu opean Union no
he g an ing au ho i y can be held esponsible o hem.
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Me ology, co- inanced om he Eu opean Union’s Ho izon Eu ope
Resea ch and Inno a ion P og amme and by he Pa icipa ing S a es.
1 o 2
21NRM05 STASIS
D7: D a s anda d on a es me hod o measu emen o g adien magne ic
ield induced hea ing on o nea non-ac i e implan s du ing magne ic
esonance imaging submi ed o ASTM F04.15 MR.
O ganisa ion name o he lead pa icipan o he deli e able:
MR:comp (MRC)
Due da e o he deli e able: 30 Sep embe 2025
Ac ual submission da e o he deli e able: 30 Sep embe 2025
2 o 2
Summa y
As a esul s o he STASIS p ojec , he a ached documen en i led “S anda d Tes Me hod
o Tes ing g adien -induced hea ing on passi e medical implan s” was submi ed as a
wo k i em (WK95470) o he ASTM subcommi ee F04.15 on 26 h o June 2025. The kicko
mee ing o he ASTM subg oup o e alua e he d a is scheduled o Q4/2025.
In summa y, he aims o he STASIS p ojec deli e able ha e been success ully achie ed,
ul illing Objec i e 4 o he p ojec .
Designa ion: X XXXX-XX
Wo k I em Numbe : 0
Da e: 0
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This documen is no an ASTM s anda d; i is unde conside a ion wi hin an ASTM echnical commi ee bu has no ecei ed all app o als equi ed o become an ASTM s anda d. You ag ee no
o ep oduce o ci cula e o quo e, in whole o in pa , his documen ou side o ASTM Commi ee/Socie y ac i i ies, o submi i o any o he o ganiza ion o s anda ds bodies (whe he na ional,
in e na ional, o o he ) excep wi h he app o al o he Chai man o he Commi ee ha ing ju isdic ion and he w i en au ho iza ion o he P esiden o he Socie y. I you do no ag ee wi h hese
condi ions please immedia ely des oy all copies o he documen . Copy igh ASTM In e na ional, 100 Ba Ha bo D i e, Wes Conshohocken, PA 19428. All Righ s Rese ed.
Technical Con ac :
Include Ballo Ra ionale He e (Requi ed o all Ballo s):
D a Numbe (i applicable):
S anda d Tes Me hod o Tes ing g adien -induced hea ing on
passi e medical implan s
S anda dTi le1
This s anda d is issued unde he ixed designa ion X XXXX; he numbe immedia ely ollowing he designa ion
indica es he yea o o iginal adop ion o , in he case o e ision, he yea o las e ision. A numbe in pa en heses
indica es he yea o las eapp o al. A supe sc ip epsilon (ε) indica es an edi o ial change since he las e ision o
eapp o al.
1. Scope
1.1 This es me hod co e s measu emen o g adien -induced hea ing on a passi e medical
implan and i s su oundings du ing magne ic esonance imaging (MRI).
1.2 This es me hod is one equi ed o de e mine i he p esence o a passi e implan may
cause inju y o he pa ien wi h he implan du ing an MR p ocedu e. O he sa e y issues ha
should be add essed include magne ically induced displacemen o ce and o que, as well as
adio equency induced hea ing and p ope de ice unc ion while in a ious con igu a ions in
he MR en i onmen .
1.3 The amoun o g adien induced hea ing will depend on he |dB/d | ms ( oo mean
squa e alue o he ime a e o change o he magne ic ield) and on he g adien ield
o ien a ion.
1.4 This es me hod assumes ha es ing is done on de ices ha will be en i ely inside he
body. Fo o he implan a ion condi ions ( o example, ex e nal ixa ion de ices, pe cu aneous
needles, ca he e s o e he ed de ices such as abla ion p obes), modi ica ions o his es
me hod a e necessa y.
1.5 The alues s a ed in SI uni s a e o be ega ded as s anda d. No o he uni s o
measu emen a e included in his s anda d.
1 This es me hod is unde he ju isdic ion o ASTM Commi ee commi eeTi le and is he di ec
esponsibili y o Subcommi ee subcommi eeTi le.
Cu en edi ion app o ed XXX. XX, XXXX. Published XX XXXX. DOI:10.1520/XXXXX-XX
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1.6 This s anda d does no pu po o add ess all o he sa e y conce ns, i any, associa ed
wi h i s use. I is he esponsibili y o he use o his s anda d o es ablish app op ia e sa e y
and heal h p ac ices and de e mine he applicabili y o egula o y limi a ions p io o use.
1.7 This in e na ional s anda d was de eloped in acco dance wi h in e na ionally ecognized
p inciples on s anda diza ion es ablished in he Decision on P inciples o he De elopmen
o in e na ional S anda ds, Guidesand Recommenda ions issued by he Wo ld T ade
O ganiza ion Technical Ba ie s o T ade (TBT) Commi ee.
2. Re e enced Documen s
2.1 ASTM S anda ds:
F2052 Tes Me hod o Measu emen o Magne ically Induced Displacemen Fo ce on
Medical De ices in he Magne ic Resonance En i onmen
F2119 Tes Me hod o E alua ion o MR Image A i ac s om Passi e Implan s
F2213 Tes Me hod o Measu emen o Magne ically Induced To que on Medical
De ices in he Magne ic Resonance En i onmen
F2503 P ac ice o Ma king Medical De ices and O he I ems o Sa e y in he
Magne ic Resonance En i onmen
F2182 S anda d Tes Me hod o Measu emen o Radio F equency Induced Hea ing On
o Nea Passi e Implan s Du ing Magne ic Resonance Imaging
2.2 ISO S anda ds:
ISO_TS_10974_2018(E) - Assessmen o he sa e y o magne ic esonance imaging o
pa ien s wi h an ac i e implan able medical de ice
ISO/IEC Guide 99:2007 - In e na ional Vocabula y o Me ology – Basic and Gene al
Concep s and Associa ed Te ms (VIM) 3 d Edi ion
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IEC 60601-2-33:2022 - Medical elec ical equipmen - Pa 2-33: Pa icula
equi emen s o he basic sa e y and essen ial pe o mance o magne ic esonance
equipmen o medical diagnosis
3. Te minology
3.1 De ini ions:
3.1.1 gelled saline—phan om medium consis ing o sodium chlo ide and polyac ylic acid
in wa e as speci ied in his es me hod.
3.1.2 implan , n—in medicine, an objec , s uc u e, o de ice in ended o eside wi hin he
body o diagnos ic, p os he ic, o o he he apeu ic pu poses.
3.1.3 isocen e —geome ic cen e o he g adien coil sys em, which gene ally is he
geome ic cen e o a scanne wi h a cylind ical bo e.
3.1.4 magne ic esonance imaging (MRI)—imaging echnique ha uses s a ic and ime
a ying magne ic ields o p o ide images o issue by he magne ic esonance o nuclei.
3.1.5 magne ic esonance sys em (MR sys em)—combina ion, as speci ied by he MR
manu ac u e , o i ems o equipmen , a leas one o which is MR equipmen , o be in e -
connec ed by unc ional connec ion o by use o a mul iple socke -ou le
60601-2-33, Ed. 4.0
3.1.6 MR Condi ional—an i em ha has been demons a ed o pose no known haza ds in a
speci ied MR en i onmen wi h speci ied condi ions o use. Field condi ions ha de ine he
speci ied MR en i onmen include ield s eng h, spa ial g adien , dB/d , adio equency (RF)
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ields, and speci ic abso p ion a e (SAR). Addi ional condi ions, including speci ic
con igu a ions o he i em, may be equi ed.
3.1.7 MR Sa e—an i em ha poses no known haza ds in all MR en i onmen s
NOTE 1—MR Sa e i ems include nonconduc ing, nonmagne ic i ems such as a plas ic pe i dish. An i em may be
de e mined o be MR Sa e by p o iding a scien i ically based a ionale a he han es da a.
3.1.8 MR es sys em—MR sys em o an appa a us ha ep oduces he ime- a ying
g adien magne ic ield o his ype o sys em.
3.1.9 MR Unsa e—an i em ha is known o pose haza ds in all MR en i onmen s.
NOTE 2—MR Unsa e i ems include magne ic i ems such as a pai o e omagne ic scisso s.
3.1.10 passi e implan —an implan ha se es i s unc ion wi hou supply o elec ical
powe .
3.1.11 pulsed g adien magne ic ield— he magne ic ield in MRI ha is used o spa ially
encode he MR signal.
3.1.12 peak empe a u e inc ease— he spa ial maximum alue o he empe a u e inc ease
o e he implan su ace.
3.1.13 wo s o ien a ion— ela i e o ien a ion be ween dB/d ec o and implan which
causes he highes peak empe a u e inc ease.
3.1.14 implan CAD ile— ile con aining he desc ip ion o he 3D implan geome ical
model sui able o be open wi h CAD (Compu e Aided Design) so wa e.
3.1.15 measu ed empe a u e inc ease alue—quan i y alue ep esen ing he empe a u e
inc ease measu emen esul
In e na ional Vocabula y o Me ology – Basic and Gene al Concep s and Associa ed
Te ms (VIM) 3 d Edi ion
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4. Summa y o Tes Me hod
4.1 The es me hod elies on a compu a ional model p elimina y alida ed agains labo a o y
expe imen s unde s anda dized exposu e condi ions.
4.2 The passi e implan o be es ed is placed comple ely wi hin a phan om illed wi h an
app op ia e medium wi h physical p ope ies (i.e., he mal conduc i i y, he mal capaci y, mass
densi y) simila o he a e aged p ope ies o he human body. The phan om ma e ial is a gelled
saline (consis ing o a saline solu ion and a gelling agen ). The implan is exposed o a spa ially
uni o m linea ly pola ized ha monic magne ic ield.
4.3 The es p ocedu e is di ided in o ou s eps: (1) P elimina y simula ions a e ca ied ou
o de e mine he o ien a ion ela i e o he applied ield ha p oduces he la ges hea ing and he
loca ions whe e he maximum local empe a u e inc ease is expec ed. (2) The implan is placed
in he cen e o he phan om con aine and o ien ed acco ding o he simula ion ou comes.
Tempe a u e inc ease is measu ed by placing p obes on he implan su ace. (3) The
compu a ional model is e ined un il he maximum ela i e de ia ion be ween he measu ed
empe a u e inc ease alue and he simula ion esul s ob ained in he same e e ence poin is
lowe han 20 % is ob ained. When his condi ion is me , he compu a ional model is conside ed
alida ed and will ep esen he sole means o he es ing. (4) In case he compu a ional model
has been subjec ed o e inemen , he simula ions o de e mine he la ges hea ing a e epea ed
and he esul p o ides he es ing ou pu .
5. Signi icance and Use
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5.1 This es me hod desc ibes a es p ocedu e o e alua ing he peak empe a u e inc ease,
consequen o he wo s o ien a ion, induced by g adien coil powe deposi ion du ing an MR
p ocedu e, in ol ing he exposu e o a speci ic dB/d ec o . The me hod allows he
cha ac e iza ion o he p opensi y o an implan o hea , a he han he p edic ion o hea ing
du ing a speci ic MR p ocedu e in a pa ien . The esul s may be used o iden i y he implan
posi ions wi hin he scanne which gua an ee he sa e y o a pa ien wi h he implan du ing an
MR examina ion.
6. Appa a us
6.1 Tes Appa a us—The es appa a us consis s o a sui able phan om, an MR es sys em o
p oduc ion o he dB/d ield and a modeling so wa e. The phan om MR es sys em and
modeling so wa e a e u ilized o app oxima e he physical en i onmen ha he pa ien and
de ice expe ience du ing an MR p ocedu e. MR es sys em and modeling so wa e a e u ilized
o es ablish he hea ing beha io o a de ice in a known dB/d ield in a s anda dized phan om.
6.2 MR es sys em—The MR es sys em should be able o gene a e a ha monic linea ly
pola ized dB/d ec o spa ially uni o m (less han 10 %) wi hin he olume whe e he implan
will be loca ed. The de ice should be able o gene a e a |dB/d | ms alue equal o 42 T/s a a
equency no exceeding 1750 Hz. The expe imen al de ice should be able o gua an ee he
s abili y o he applied dB/d ec o (maximum accep able a ia ion less han 1 %) du ing he
du a ion o he expe imen .
6.3 Tempe a u e Senso —Tempe a u e on he implan su ace should be measu ed by using
empe a u e p obes immune o elec omagne ic in e e ence (e.g., op ical p obes). The sensi i e
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elemen s should ha e a side lowe han 1 mm. The p obe accu acy should be lowe han ±0.1 °C
close o he calib a ion poin (23 °C).
6.4 Modeling so wa e—A s a e-o -a elec omagne ic and he mal modeling so wa e
should be used o he simula ions. The so wa e should be able o impo he implan CAD ile
o be es ed and disc e ize i on he basis o he adop ed ma hema ical me hodology.
7. Tes Specimens
7.1 While his es me hod may be used on p o o ype o p edica e de ices, o pu poses o
implan quali ica ion and o ensu e pa ien sa e y ela i e o he use o MRI echnology, he
implan e alua ed acco ding o his es me hod should be ep esen a i e o a inished de ice
acco ding o i s in ended use o in-si u condi ion.
7.2 O he han desc ibed as in 7.1, o pu poses o implan quali ica ion, he implan shall no
be al e ed in any manne p io o es ing o he han posi ioning o o he wise con igu ing he
implan in he o ien a ion ha gene a es he g ea es hea ing. A jus i ica ion o such
o ien a ion shall be p o ided h ough simula ions.
8. Reagen s and Ma e ials
8.1 When using a phan om wi hin an MR es sys em, he e a e o en p ac ical limi a ions o
he phan om con aine size, and he bounda y condi ions o he phan om can a ec empe a u e
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11. Keywo ds
11.1 exposu e; gelled-saline; implan ; MRI (magne ic esonance imaging); MR sa e y;
phan om; g adien -induced hea ing; dB/d .
ANNEX
(Manda o y In o ma ion)
A1. PHANTOM THERMAL PROPERTY MEASUREMENT
A1.1 Gene al conside a ions
Fo a gi en ecipe se , he pa ame e s should be assessed and demons a ed a leas once.
Reliable empe a u e measu emen s can only be conduc ed i he G asho numbe is su icien ly
la ge, i.e. he iscosi y o he medium o gel should be much la ge han 1 Pa∙s. An app op ia e
me hod o measu ing he iscosi y should be selec ed, e.g. heome e s. The iscosi y should be
de e mined o he en i e empe a u e ange, o which he lowes numbe should be used.
This subclause desc ibes wo me hods o de e mine he hea capaci y o issue simula ing media
used o implan es ing. Fu he mo e, i is necessa y o demons a e ei he by simula ion o by
expe imen ha he e ec o hea conduc ion and con ec ion a e negligible in he assessmen o
GC hea ing o he maximum spa ial g adien , empe a u e di e ence and du a ion o hea ing.
The simula ion app oach can be used when he he mal conduc i i y and he G asho numbe a e
known. I can also be demons a ed by expe imen o he condi ions o maximum spa ial
empe a u e g adien T, empe a u e di e ence (ΔT) and du a ion o assessmen (Δ ). The
demons a ion o negligible e ec s ela ed o conduc ion and con ec ion is no equi ed o
o mula ions ha con ain g ea e han 95 % wa e and he p ope ies o wa e can be used.
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A1.2 Me hod o de e mine hea capaci y
The mos common way o de e mining he speci ic hea capaci y is di e en ial scanning
calo ime y. I can be used o de e mine speci ic hea capaci y as a unc ion o empe a u e as
well as he loca ion o phase ansi ion empe a u es ( ele an o gels). The empe a u e o he
unknown sample and o a e e ence ma e ial is changed in he same way acco ding o a
p ede ined cu e wi h cons an cooling and hea ing a es. A a cons an a e he empe a u e
di e ence obse ed be ween he e e ence ma e ial and i s su oundings is he esul o he
di e en hea capaci ies o he e e ence ma e ial and he su ounding ma e ial. The ime
dependence o he empe a u e di e ence is measu ed. The di e en ial scanning calo ime e is
calib a ed wi h he known e e ence ma e ial, any empe a u e di e ence can be di ec ly
con e ed in o hea low. In such a way he hea capaci y is de e mined as a unc ion o he
empe a u e.
A1.3 Me hod o de e mine he mal conduc i i y
The ho wi e me hod is app op ia e o de e mining he mal conduc i i y. A hin wi e is
embedded in o he sample o be in es iga ed, simul aneously se ing as a hea ing elemen and a
empe a u e senso . Du ing he expe imen , he wi e is hea ed wi h a cons an elec ical powe
sou ce. The empo al de elopmen o he inc ease in empe a u e a he ho wi e is calcula ed
om he esis ance o he wi e. This empe a u e inc ease is p ima ily dependen on he he mal
conduc i i y o he sample. The he mal conduc i i y is de e mined by conside ing bo h he
he mal con ac esis ance be ween he sample and he wi e and he axial hea losses o he
empo al empe a u e de elopmen .
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A2. THERMAL MATRICES
A2.1 In oduc ion
The ollowing s eps should be ollowed o compu e he The mal Ma ices . The The mal
Ma ices allow o compu e he empe a u e inc ease in he posi ions o he implan o be es ed,
, acco ding o:
whe e is he ime-de i a i e o he linea ly pola ized, spa ially uni o m, ha monic magne ic
ield ec o causing he empe a u e inc ease.
The The mal Ma ices also allow o compu e he peak empe a u e inc ease ob ained when he
implan o be es ed is exposed o he wo s dB/d ec o and he di ec ion o he he wo s dB/d
ec o .
The ollowing nomencla u e is adop ed:
: he he mal ma ix associa ed wi h poin o he implan o be es ed
: empe a u e inc ease in when he implan o be es ed is exposed o 30 minu es
o a speci ic dB/d ec o
: he uni a y ampli ude dB/d ec o esponsible o he peak empe a u e
inc ease on he implan o be es ed
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: he peak empe a u e inc ease when he implan o be es ed is exposed o 30
minu es o
: maximum empe a u e inc ease in conside ing a 30 minu es exposu e o all
possible dB/d ec o s wi h uni a y ampli ude
: empe a u e inc ease in conside ing a 30 minu es exposu e o a uni a y
ampli ude dB/d ec o o ien ed along he j- h Ca esian di ec ion.
: empe a u e inc ease in conside ing a 30 minu es exposu e o a dB/d ec o
wi h uni a y ampli ude along bo h he j- h and k- h Ca esian di ec ions wi h .
A2.1 The mal Ma ices Compu a ion
Six elec omagne ic simula ions ollowed by ansien he mal simula ions a e pe o med o
compu e he The mal Ma ices . Whe eas i is possible o compu e such ma ices also o
poin s in he phan om o inside he implan , o he pu pose o he p esen es ing p ocedu e i
su ices o limi hei compu a ion o he posi ions on he implan su ace.
1. Compu e he empe a u e inc ease, , in each posi ion when he implan o be
es ed is adia ed by a uni a y ampli ude dB/d ec o o ien ed along each j- h Ca esian
di ec ion.
2. Compu e he quan i ies as
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ep esen he diagonal elemen s o he The mal Ma ix
3. Compu e he empe a u e inc ease , in each in each posi ion when he implan
is adia ed by a dB/d ec o wi h uni a y ampli ude along bo h he j- h and k- h
Ca esian di ec ions wi h .
4. Compu e he quan i ies as
ep esen he o -diagonal elemen o The mal Ma ix
5. Cons uc he The mal Ma ices
The p ocedu e allows o compu e a numbe o 3 x 3 The mal Ma ices equal o he numbe o
posi ions conside ed.
A2.2 Peak Tempe a u e Inc ease and Wo s dB/d Vec o Compu a ion
The ollowing s eps allow o compu e he peak empe a u e inc ease and he dB/d ec o
esponsible o he peak empe a u e inc ease on he implan o be es ed.
1. Compu e he maximum eigen alue o all he The mal Ma ices . This co esponds
o he quan i y
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2. Compu e he maximum among all he . This co espond o he quan i y
and i is eached in poin :
3. Compu e he uni a y ampli ude eigen ec o associa ed wi h he eigen alue o
he The mal Ma ix . This co esponds o
4. Compu e he peak empe a u e inc ease due o an exposu e o a 42 T/s dB/d
ec o o ien ed as :
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APPENDIX
(Nonmanda o y In o ma ion)
X1.
X1.1 In oduc ion
The p oposed es allows e ie ing he peak empe a u e inc ease on he implan o be es ed
when exposed o he dB/d ec o ha maximizes he hea ing. Whe eas his esul gua an ees a
conse a i e sa e y app oach, i can esul in impo an o e es ima ion o he ac ual peak
empe a u e inc ease o s ongly aniso opic implan s. Fo hese implan s he wo s dB/d ec o
o ien a ion could lead o much highe empe a u e inc eases wi h espec o hose due o he
ac ual dB/d ec o s gene a ed by an MRI scanne . Since hese depend on he scanne g adien
coils and he MR pulse sequence, any in o ma ion ela ed o he implan geome y has o be
in e aced o he MRI scanne in o de o be e ec i e. Fo his eason he p oposed es is
es ic ed o p o ide he peak empe a u e inc ease when he implan is exposed o he wo s
dB/d ec o . Anyway, whene e equi ed, i is possible o compu e so-called Aniso opy
Coe icien s which in oduce addi ional in o ma ion abou he geome y o he implan o be
es ed. The Aniso opy Coe icien s, combined wi h he in o ma ion o he magne ic ield
gene a ed by he g adien coils and he MR pulse sequence wa e o ms, allows o inc ease he
maximum |dB/d | ms a which he implan o be es ed can be sa ely scanned. This po en ially
a oids he exclusion o sa e scanning scena ios.
In pa icula , he gene a ed by a speci ic MR g adien coil se and MR sequence in he
posi ion inside he scanne bo e, can be exp essed as:
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whe e:
is he he magne ic ield p oduced by he i- h g adien coil when he g adien a he
isocen e is 1 T/m along he coil e e ence di ec ion
and is he g adien in T/m gene a ed by he i- h
g adien coil du ing he MR sequence execu ion
TR is he epe i ion ime o he MR sequence
In absence o he skin e ec , he empe a u e inc ease scales wi h he squa e o he .
Wi h he exp ession abo e i is he e o e possible o limi he posi ions o an implan wi hin hose
whe e he peak empe a u e inc ease o e he implan su ace will be lowe han a speci ic alue.
As such, he ep esen s a sa e y index, , whose alue should no be exceeded in
o de o gua an ee sa e y. Howe e , he abo e exp ession b ings no in o ma ion abou he
aniso opy o he implan and he is limi ed independen ly o he di ec ion o he
ec o . To add such an in o ma ion, he Aniso opy Coe icien s a e in oduced. These
coe icien s ange om 0 o 1 and a e used o educe he alue o o a speci ic
ec o acco ding o:
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This appendix desc ibes how he Aniso opy Coe icien s, , can be compu ed. The Aniso opy
Coe icien s encode he in o ma ion abou he shape o he implan o be es ed and can be used,
oge he wi h he maximum peak empe a u e inc ease a a o 42 T/s, o iden i y
g adien -sa e ope a ing a eas o he implan o be es ed inside an MR scanne unning an MR
sequence.
The appendix assumes ha he The mal Ma ices a e a ailable o all he posi ions
conside ed in he simula ions. Fu he mo e, i assumes he implan unde es is o ien ed in o he
phan om acco ding o he expec ed o ien a ion inside he scanne wi h he z-axis co esponding
o he in e io (I) o supe io (S) di ec ion, he x-axis co esponding o he le (L) o igh (R)
di ec ion and he y-axis o he an e io (A) o pos e io (P) di ec ion.
X1.2 Aniso opy Coe icien s Compu a ion
The ollowing s eps desc ibe how he Aniso opy Coe icien s can be ob ained.
1. De ine a numbe o di ec ions ac oss he hemisphe e wi h a longi ude be ween −180°
and 180° and a la i ude be ween 0° and 90°. The angula s ep mus be a leas 22.5° in
o de o map sa is ac o ily he hemisphe e.
2. Fo each uni a y ampli ude ec o , compu e:
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