Porto Caval Shunts

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0 36 1 - 80 3X /9 0/ 1 5 42 -0 39 3 Am er ica n R oen tg en Ra y S oc ie ty

Th irty - tw o por to sys tem ic sh un ts in 31 pa tie n ts w e re e va lu a te d w ith co lo r an d dup le xD opp le r im ag in g . The age s o f the pa tie n ts a t th e tim e o f so nog raph ic e xam in a tion ran ged

Co lo r D opp le r Im ag ing o fPo rtosys tem ic Shun ts

Edwa rd G . Gran t1F ran k lin N . Te ss le r1

An to ine tte S . G om es1C hon ita L . H o lm es1R ita R . P e rre lla1

And re J . D uen inckx1R ona ld W . Busu tt il2

R ece ive d Ju ly 1 7 , 1 989 ; a ccep ted a fte r re v is ionSep tem be r 1 9 , 1 98 9 .

1 D ep artm en t o f R ad io lo gica l S cien ce s, U niv er-s ity o f C ali fo rn ia , L os A nge le s , S chco l o f M ed ic in e ,10833 LeC on te A ve ., L os A nge le s , C A 90024 . A d-d res s re p rin t re qu es ts to E . G . G ra n t.

2 D ep artm en t o f S urge ry , U nive rs ity o f C alifo rn ia ,Lo s Ange les , S chco l o f M ed ic in e , L os Ange les , C A90024 .

Th is s tudy w as des igned to in ves tig a te th e u tility o f co lo r D opp le r sonog raphy in th eeva lua tio n o f po rto sys tem ic shun ts . Th irty -one pa tie n ts w ith a to ta l o f 3 2 shun ts w ereim aged . The types o f shunts exam ined in c luded po rtac ava l, five ; m esocava l, e ig h t;d is ta l sp leno rena l(W arren ), 1 4 ; and m esoa tria l, fiv e . S onog raphy w as p erfo rm ed w ith ou tknow ledge o f th e s ta tu s o f th e shun t , a lth ough th e type o f shun t w as know n be fo rebeg inn ing the s tudy . T he sonog raph ic s tud ie s we re eva lua ted to de te rm ine the ir sens i-t iv ity and spec ific ity on th e bas is o f a pro spec tive com par is on w ith ang iog raphy o r M Rim ag ing (2 2 cases ). T h e poss ib le advan tages o f co lo r D opp le r o ve r dup le x D opp le rsonog raphy in eva lua tin g po rto sys tem ic shun ts w ere a lso in ves tig a ted , as w as th eab ility o f co lo r D opp le r sonog raphy to im age spec ifica lly th e shun t anas tom oses . C o lo rDopp le r sonog raphy successfu lly in fe rred shun t p a tency (1 7 cases ) o r th rom bos is (fiv ec ases ) in a ll 2 2 shun ts fo r w h ich co rre la tiv e im ag ing w as ava ilab le (s ens itiv ity = 1 0 0% ,spec i f ic i ty = 100%) . In com par ing dup le x w ith co lo r Dopp le r sonography in a ll 32 shun ts ,th e tw o techn iques w e re a lm os t equa lly e ffe c tiv e in e s tab lish ing pa tency in po rta c ava l,m esocava l, and m esoa tr ia l shun ts . D up lex D opp le r sonog raphy , however, p rov ideduse fu l d ia gnos tic in fo rm a tion in on ly fou r o f 1 4 sp leno rena l shun ts . C o lo r D opp le rcorrec t ly in fe rred pa tency o r th rom bos is in a ll 14 . Am ong a ll 3 2 shun ts , th e anas tom os isw as show n c lea rly b y co lo r D opp ler in 2 3 , p robab ly in fou r , and no t a t a ll in five .

O ur resu lts su gg es t th a t c o lo r Dopp ler so nograph y is an ex ce lle n t m etho d fo r th eeva lua tio n o f a ll va rie ties o f su rg ic a lly c re a ted po rto sys tem ic shun ts . In p a rt ic u la r , c o lo rD opp le r sonog raphy appears to be supe rio r to dup le x Dopp le r sonog raphy in im ag ings ple no re na l c om m un ic atio ns .

AJ R i 54 :393 -397 , February 1990

Po rto sys tem ic shun ts a re cons tru c ted to pa llia te sym p tom a tic po rta l h ype rten -s ion [i , 2 ] o r to prov ide decom p ress ion o f the hepa tic vascu la tune in pa tien ts w ithB udd -C h ian i synd rom e [3 ]. A ll such shun ts m ay th rom bose occas iona lly , thoughthe fre quency va r ie s w ith the typ e o f shun t [4 , 5 ]. A cu te b lockage o f a po rtosys tem icshun t m ay resu lt in a life -th rea ten ing recu rrence o f sym p tom s .

A ng iog raphy has been the de fin itiv e m e thod o f eva lua ting po rto sys tem ic shun tsfo r som e tim e . H oweve r, a n g iog ra ph y is in va s ive , a nd th e ana tom ica lly iso la tedpo rta l sys tem m ay be d ifficu lt to opac ify [6 ]. N um e rous im ag ing techn iques ,in c lud ing nea l- tim e sonog raphy [7 ], con tra s t-enhanced C T [8 , 9 ], and M R im ag ing[i 0 ], have been used to eva lua te po rto sys tem ic shun ts non invas ive ly . R ecen tly ,dup le x D opp le r sonog raphy has been used in th is re ga rd as w e ll [9 , 1 i - 1 6 ]. There su lts o f eva lua tions w ith dup lex Dopp le r sonog raphy have been encou rag ing , bu th igh ly dependen t o n th e lo ca tion o f th e shun t [9 , 1 i , i 5 ]. W e undertook th is s tudyto assess the poss ib le ro le o f co lo r D opp le r im ag ing in the eva lua tion o f su rg ica llyc rea ted po rtos ys tem ic shun ts .Sub jects and M ethods


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F ig . 1 -P o rtac ava l s hun t.A an d B , Lon gitud in al (A ) a n d t ra n sv e rs e (B ) co lo r D opp le r im ag es show com mun ic a t ion be tw een

porta l ve in an d in fe rio r ve na cava (IV C ) ( arrows) . C on s id erab le tu rbu len ce is comm on at sh un tana stom oses , a s e v id en ced b y m ix tu re o f co lo rs in the se a re as . D ur in g po rtions o f c ard ia c cyc le ,b loo d m ay re flux in to p orta l s ys tem in respon se to no rm al ph as ic flow re ve rsa ls in ivc. No te redco lo r in p orta l ve in (B); flow is d irec te d tow ard Dopp le r b eam .

F ig . 2 .-M eso atria l s hu n t . Lo ng itu d ina l co lo rDopp ler im ag e show s flow w ith in sup er fic ia l, su b -co sta l po rtio n o f m esoa tria l s hu n t . N o te b rig h tlyechogen ic w a lls o f s yn the tic sh un t ( arrows) . Al -th ou gh flow in shun t is d irec ted tow ard r igh ta tr ium, co lo r ch an ges from red to b lu e a s flowadvan ces and re cedes in re la tio n to Dopp le r b eam .

39 4 GRANT E T AL . A JR :1 54 , F eb rua ry 1 990

from 1 7 to 70 ye ars (m ean , 4 1 ye ars ). S ix tee n m en and 1 5 wom enw ere eva lu a te d . F ou rte en o f th e 3 1 pa tie n ts w e re re fe rre d to o u rins titu tion fo r po ss ib le live r tran sp la n ta tio n . T he se 1 4 pa tie n ts under-w en t co lo r an d d up lex Dopp le r im ag in g o f th e en tire po rta l v en ou ss ys tem as pa rt o f the ir p reo pera tive e va lu a tion s . F ou rtee n pa tie n tsw ere re fe rre d sp ec ifica lly fo r eva lu a tio n o f shu n t p a ten cy ; th re eadd itio na l sh un ts w e re ide n tifie d o n sonogram s ob ta ine d fo r o th e rre a son s . F ifte en o f the 31 pa tien ts w e re sym ptom a tic w ith as c ite s o rre cen t g as tro e sophagea l h em orrh a ge a t the tim e the sonog ram wasob ta ine d . T he se 1 5 sym p tom at ic pa t ien ts w e re from bo th th e p re -tran sp lan ta tion a nd non transp la n ta tio n g rou ps .

U nder ly in g d is ease pro ce sse s in c lude d ch ron ic ac tiv e he pa titis (10pa tie n ts ), p rim ary b ilia ry c irrho s is (s ix p a tie n ts ), B udd-C hia ri sy nd rom e(s ix p a tien ts ), a lc oho lic live r d is ea se (s ix pa tie n ts ), sc le ro s in g cho lan -g itis (on e pa tie n t), cys tic fib ros is (on e pa tie n t), an d hem och rom ato s is(o n e pa tie n t). T he typ e s o f s hun ts e n coun te re d w ere va rie d : po rta -ca va l (f ive ), m esocava l (e ig h t), d is ta l sp le n o re na l (1 4 ), an d m esoa tria l(f ive ). Th e tim e be tw een con struc t ion o f th e shun t an d the in it ia lso no gra ph ic eva lu a tio n ran ge d from 1 da y to 9 yea rs . T he re su lts o fc olo r im ag in g in ou r in itia l th re e pa t ien ts ha ve b een rep o r ted e lse -w he re [1 5 ].

A ll D o pp le r s tud ies we re p e r fo rm ed w ith a com m erc ia lly ava ila b leun it (U ltram ark 9 , A d van ced Te chno lo gy Labora to r ie s , B o the ll, W A).D up le x and co lo r D opp le r im ag ing w as pe rfo rm ed w ith p ha sed- a ndlin ea r-a rra y te ch no lo gy ; 2 .25 -, 3 .5 -, an d 5 .0 -M H z tra nsdu ce rs w e reused . A t th e beg inn in g o f the e xam ina tio n , th e pa tie n ts ch a rt w a sre v iewed to de te rm in e th e ty pe o f s hu n t p resen t. The so no log is t d idno t kn ow if the sh un t w as cons ide re d pa ten t o n c lin ic a l g ro unds andhad no know ledge o f the re su lts o f o the r im ag in g p ro cedu re s . T hee xpec te d a rea o f the shun t w a s scanned firs t w ith d up le x D opp le ran d th en w ith co lo r D opp le r im ag in g . T he sonog raph ic s tu d ies w e reth en eva lu a ted to a dd res s th ree spe c ific qu es tio ns : (1 ) W hat a re th esen s itiv ity an d spe c ific ity o f co lo r D opp le r s onog ra ph y in th e e va lu a -tio n o f p o rtosy s tem ic sh un ts? (2 ) Is co lo r su pe rio r to d up lex D opp le rin a sse ss ing po rtos ys tem ic sh un ts? (3 ) C an co lo r D opp le r im ag in gre lia bly d ep ic t sh un t an as tom ose s?

T he cr ite r ia fo r in fe rr ing shu n t pa ten cy va ried con s id e rab ly d ep end-in g o n th e type o f sh un t u nder inv es tiga tio n . F o r p o rta ca va l a nd

sp le no ren a l s hun ts to b e co ns ide red p a te n t, ap p ro p ria te ly d irec tedflow had to be v is ua liz ed in bo th lim bs o f the shu n t (p o rta l ve in /in fe rio r ve na ca va fo r po rtaca va l, s p len ic v e in /re na l ve in fo r sp le n o -re n a l). F o r m esoa tria l a n d m eso ca va l sh un ts , v isu a liza tio n o f ap p ro -p ria te ly d ire c te d flow in an y port ion o f the s yn the tic gra ft w a s ta kento im p ly pa ten cy . S ens itiv ity a nd spe c ific ity w ere de te rm in ed b ycom pa ring the res u lts o f co lo r D opp le r so nog raph y w ith a ng io g raphyand /o r M R im ag in g . A ng io g ra phy was pe rfo rm ed 1 4 tim es and M Rim ag ing 1 1 tim es in a to ta l o f 22 pa tien ts . A ng iog ra ph y was pe rfo rm edw ith s ta nda rd te chn iq ue . S e le c t ive ce liac (a nd /o r s p le n ic ) a nd supe rio rm esen te ric a rte ry in je c tio n s w ere pe rfo rm ed in a ll pa tie n ts . In som eca ses th e shun ts w ere en te re d d ire c tly . H epa tic ve in w edge p ressu re sw e re ob ta in ed a s ind ica ted . M R im ag in g was pe rfo rm ed w ith sp in -e ch o t ec hn iq ue i n o b li qu e , a x ia l, an d co rona l p ro je c tio n s . C orre la tiv eim a g in g p ro ced ures we re rev iew ed by o ne m em ber o f ou r g ro up w hohad no know le dge o f the re su lts o f th e sonog raph ic s tud ie s . T here su lts o f the sonog ram s w e re th en com pa red w ith M R im ag ing andang iog rap hy in a b lind ed fa sh ion . Se ns itiv i ty an d spe c ific ity o f co lo rD opp le r im ag in g we re ba sed on th e re su lts in th ese 2 2 s hu nts .

The resu lts o f du p le x v s co lo r D opp le r im ag in g we re the n com pa redin a ll 3 2 po rto sys tem ic shu n ts . D u p le x D opp le r exam ina tio ns w erepe rfo rm ed in th e u sua l m anne r. T he shun t w a s firs t loc a te d , ifp o ss ib le , us in g rea l tim e . T he Dopp le r cu rso r w a s th e n appro p r ia te lyp la ce d w ith in the shun t an d its p a te nc y was e s ta b lish e d on the ba s iso f rece iv in g th e e xpec te d D opp le r s ig na l. A dup le x D opp le r s tu dyw as cons ide re d un su cce ss fu l if re a l-t im e v isu a liza tio n o f th e shun t(o r the lim b s o f th e shun t as desc rib ed abo ve fo r c o lo r D opp le rim a g in g ) w a s insu ffic ie n t to a l low adequa te p lacem en t o f the Dopp le rcu rso r .

T he ab ility o f co lo r D opp le r im ag in g to d ep ic t sh un t an a s tom ose sa ls o was eva lua ted in a ll 3 2 shun ts .

Resu l tsAng iog raphy and /o r M R im ag ing dem onstra ted shun t pa -

te nc y in 1 7 o f 22 case s ; fiv e shun ts w e re occ lu ded . C o lo rD opp le r sonognaphy success fu lly dem onstra ted shun t pa -te nc y in a ll 1 7 (F ig s . i -4 ). O cc lu s ion w as a ls o d iag nosed


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F ig . 3 .-M eso ca va l s hun t.A , Lo ng itu d in a l co lo r Dopp ler im age show s su -pe rio r m esen teric v e in (S MV ) an terio r to s yn the tic

g ra f t ( arrow) . Co lo r s ig na ls a re o ften im poss ib leto d em on stra te th ro ughou t an en tire g ra f t in oneim ag e b ecau se o f chang ing re la tio nsh ip be tw eenflow d ire c tion an d D opp le r b eam .

B, P atenc y o f m eso cava l shu n t in ano th er pa -tie n t is co n firm ed by show ing flow en tering d is ta lin fe rio r vena c av a ( I) from ano the r d ire c t ion . W ithpe rs is te n t s can n ing , w a lls o f s hu n t w ere even tu -a ll y a pp re c ia te d ( c ur v ed arrow) . N ote p os te rio racou stic sh ad ow ing from gra ft w a lls (s tra igh t a r-rows) .

F ig . 4.-D is ta l sp le no re na l shun t. F ig . 5 .-T h rom bos is o f m esoa tria l sh u n t is in -A , Rea l- tim e im ag e from dup lex Dopp le r sc an pe rfo rm ed v ia a le f t a n te rio r ap proach . N o m ajo r d ic a te d by com p le te abs en ce o f co lo r w ith in e ch o -

v es se ls are iden tifie d in e xp ected a rea o f sp le n ic lim b o f W arren shun t. gen ic w a lls ( arrows) .B, Co lo r Dopp le r im ag e from sam e lo ca t ion c lea rly show s flow in sp le n ic v e in (S ) co urs in g tow a rd

le ft ren a l v e in . A nastom os is and le ft ren a l v e in w ere im ag ed b y sc an n in g from o th er van ta ge po in ts .D up lex Dopp ler s on og raph y is unsucce ss fu l in the se s itua tio ns .

AJR :154 , Feb ru a ry 19 90 CO LOR DOPPLER O F PORTO SYSTEM IC SHUNTS 39 5

co rre c tly in th e rem a in ing five (F ig . 5 ). S pe c ific ity a n d sen s itiv -ity , the re fo re , w e re 1 00% . T hese find ings a re summ arized inTab le 1 . In one o f the 1 7 pa tie n ts , a s p len o rena l sh un t w a sshow n to be pa ten t b y bo th s onog ra ph y and M R im ag ing .M R im ag in g , h ow ever, s howed a narrow in g o f a sm a ll le ftre na l ve in as it p a ssed be tw een the super io r m esen ten ic a rte ryand the aorta . A t the tim e o f th e sonog ram , the le ft re n a l ve inco u ld n o t be fo llow ed a s fa r a s the aor ta . W h ile th is sh un tw a s pa te n t, its fu nc tion m ay ha ve been com p rom is ed . B o thsonography and M R im ag in g show ed the le ft re na l ve in to bed ra in ing in to la rge re tno pen ito nea l co lla te na ls . T h is pa tie n t w asno t s ym p tom atic a t th e tim e o f th e sonogram .

In com pa ring co lo r and dup lex D opp le r sonognaphy in a ll32 shun ts , w e found tha t a ll po rtacava l and m esoa tria l shun tsw ere adequa te ly eva lua ted by bo th techn iques . D up lex Dop -p Ie r w a s a lso su cce ss fu l in th e e va lu a tio n o f se ven o f e igh tmesocava l shun ts (see F ig . 3B ). C o lo r D opp le r sonog raphyco rrec tly assessed pa tency in a ll 1 4 sp lenonena l shun ts . D u -

p le x D opp le r sonog raphy , how eve r, fu lfille d ou r c r ite r ia fo r asuccess fu l s tudy in on ly fou r o f i 4 sp leno rena l shun ts(Tab le 2 ).

Am ong the 32 shun ts , the anas tom os is w as im aged byco lo r D opp le r sonog raphy c lean ly in 23 , p robab ly in fou r, andno t a t a ll in five (T ab le 3 ) .

Discuss ionSonognaphy has been advoca ted s in ce 1 977 as a non in -

vas ive m e thod o f eva lua ting porto sys tem ic shun ts [6 ]. S o -nognaphy is pa rticu la rly app lic ab le in acu te ly ill o n uncom fo rt-ab le pa tien ts . In add ition , the inhe ren t p rope rtie s o f sonog ra -phy m ake it an a ttra c tive screen ing p rocedu re im m ed ia te lya fte r p la cem en t o f a shun t o r be fo re liven transp lan ta tion .U n fo rtuna te ly , the use o f nea l- tim e sonog raphy in the eva lua -tion o f po rto sys tem ic shun ts has been lim ited , s in ce its ana -tom ica lly or ien ted im ages can on ly sugges t pa tency . D up lex


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396 GRANT ET AL . AJR :1 54 , F ebrua ry 1 99 0

TABLE 1: S en s it iv ity an d S pec ific ity o f Co lo r D opp ler Im ag ingin th e Eva lu a t ion o f P ortos ys tem ic S hun ts

T ype o f S hun t Ang io g ra ph y /MRC orre ctly D ia gn os ed

b y C olo r D op ple rImag inga te n t T h rom bosed To ta l

Po r tacava l 3 1 4 4M esoa tria l 3 2 5 5M esocava l 5 1 6 6Sp leno rena l

To ta l6 1 7 7

17 5 22 22

TAB LE 2 : D up le x vs C o lo r D opp le r Im ag ing in th e Eva lu a tio n o fP or tos ys tem ic Shun ts

T ype o f S hun t To ta l.

A dequa te S hun tVisua l iza t ionDup le x C o lo r

Po rta cava l 5 5 5M esoa tn ia l 5 5 5M esocava l 8 7 8Sp leno rena l

To ta l1 4 4 1432 21 32

TAB LE 3 : A b ility o f C o lo r D opp ler to Im age Shun t A nastom oses

T ype of S hun t To ta lNo . Im aged NotImaged Quest ionab lePo r ta cava l 5 4 1 0Mesoa tr ia l 5 2 3 0M esocava l 8 8 0 0Sp leno rena l

To ta l1 4 9 1 432 23 5 4

D opp le r sonognaphy , how eve r, p rov ides phys io log ic flow in -fo rm a tion and has been used success fu lly by a num be r o fau tho rs in the eva lua tion o f po rto sys tem ic shun ts [9 , 11 -1 6]. C o lon im ag ing is the la te s t re finem en t o f sonog raph ictechno logy , and its p o ten tia l in the e va lua tion o f p o rtosys -tem ic shun ts has no t, to ou r know ledge , been inves tiga ted .Co lon D opp le r sonognaphy was capab le o f d ire c tly im ag ingshun t flow and in fe rr ing pa tency vs th rom bos is in a ll pa tien ts .Sensit iv ity a nd spec ific ity w ere 1 00% in our se ries .

P re v io us s tud ies o f po rtosystem ic shun ts us ing dup le xD opp le r sonography have found th e te chn ique to be re la tive lyaccu ra te . The succe ss o f dup lex D opp le r sonognaphy, how -e ve r, is la rge ly dependen t upon the loca tion o f the shun t.D up lex D opp le r sonog raphy can im age portacava l and m e -soa tn ia l shun ts qu ite adequa te ly . O u r s tudy co rrobo ra tes ea r-lien w ork in th is re ga rd [i 0 , i 2 -i 4 ]. A ltho ugh co lo n D opp le rsonognaphy incre ased con fiden ce and m arked ly lessenedscann in g tim e , it o ffe red no true d iagnos tic ad van tage ovendup lex D opp le r in im ag in g the se tw o types o f shun ts . O urre su lts a lso ind ica te tha t m esocava l shun ts a re m os t o ftenadequa te ly im aged by dup lex Dopp le r sonography . In ou rexpe rience , rea l-tim e scann ing , in fa c t, typ ica lly iden tifie d theechogen ic wa lls o f th e syn the tic g ra ft m ore read ily th an co lo r

Dopp le r im aged the flow w ith in . O nce the g ra ft w as lo ca ted ,e ithe r co lo r or dup le x D opp le r sonognaphy cou ld be used toes tab lish pa tency . O f a ll s hun ts , D opp le r s igna ls w e re them os t d iffic u lt to e lic it from w ith in the syn the tic w a lls o f m e-socava l g ra fts . In the s ing le m esocava l shun t tha t w as no tseen w ith dup lex Dopp le r sonognaphy, the in itia l fea tu re iden -tifie d by co lon D opp le r sonognaphy was the p resence o f aloca lized a rea o f re ve rsed flow in th e m id -d is ta l in fe rio r venacava . A s the in fe r io r vena cava has no m a jo r in fra rena lb ranches , such flow cou ld on ly be from the pa tien ts shun t.D up lex Dopp ler sonog raphy w as no t capab le o f g raph ica llydep ic ting th is flow phenom enon and w as unsuccess fu l in th iscase .

W hile dup lex Dopp le r im ag ing has been cons ide red a s apo ten tia l sc reen ing p rocedu re fo r a ll types o f po rto sys tem icshun ts , a rev iew o f the lite ra tu re revea ls tha t m ost o f thepa tien ts s tud ied had po rta cava l comm un ica tions [i i - is ].U n fo rtun a te ly , po rtaca va l sh un ts a re be in g cons truc te d lessfrequen tly as liv e r transp lan ta tion becom es an accepted fo rmo f th e rap y fo r pa tien ts w ith end -s tage liven d isease and porta lh ype rtens io n . M esocava l a nd sp lenonena l shun ts , the re fo re ,a re be ing pe rfo rm ed m ore frequen tly . A lthough dup lex D op -p Ie r sonog raphy has been re la tiv e ly success fu l w ith m esoca -va l shun ts , the eva lua tion o f d is ta l sp lenonena l shun ts hasbeen p rob lem a tic . F o le y e t a l. [9 ], in fac t, sp ec ifica lly a d -d ressed le ft uppe r quad ran t shun ts and found dup lex D opp le rs on ogn ap hy th oro ug hly in adequa te . O ur re su lts w ith dup lexD opp le r sonog raphy, though som ew ha t be tte r th an tho se o fFo ley e t a l., w e re s til l d isappo in ting . T he venous lim bs o fsp lenonena l shun ts w e re v isua lized by rea l tim e in on ly fou ro f i 4 cases . A dequa te p la cem en t o f a Dopp le r cu rso r, the re -fo re , w as not poss ib le . C o lo r Dopp le r sonognaphy, on theo the r hand , was fa n m ore successfu l in the le ft uppe r quad -ran t. T he co lo r Dopp le r im age was v is ib le th rough a re la tiv eve il o f bowe l gas and backsca tten . A dequa te v isua liz a tion o fthe sp len ic and rena l lim bs o f W a rren shun ts was poss ib le ina ll o f ou r pa tien ts . W h ile the th in wa lls o f na tive ve ins a re no tb righ tly echogen ic , they appa rently o ffe r little im pedance toth e tran sm iss ion o f the D opp le r b eam . The im p lan ted sp le n icve in is ea s ily lo ca ted w ith co lon D opp le r im ag ing .

W hile co lo r Dopp le r im ag ing was capab le o f in fe rring shuntpa tency in a ll pa tien ts in ou r se rie s , the shun t anas tom os iswas som ew ha t m ore cha lleng ing to f ind . A s e xpecte d , v is ib il-ity va ried w ith the type o f shun t be ing eva lua ted . The anas-tom os is be tw een the po rta l v e in and the in fe r io r vena cavaw as seen read ily in a lm ost a ll pa tien ts . T he liv e r p rov ided anexce lle n t acous tic w in dow . L ikew ise , the jun ctio n be tw eenthe syn the tic g ra ft and the in fe rio r vena cava in m esocava lshun ts w as read ily im aged once an app rop r ia te acous ticw indow w as found . D em onstra tio n o f the anas tom oses inm esoa tr ia l and sp lenonena l shun ts , howeve r, w as m o re com -p lica ted . In m esoa tria l shun ts , the junc tio n be tween the su -pe rion m esen te ric ve in and the g ra ft lies deep w ith in theabdom en . T h is reg ion is no to r ious ly d iffic u lt to eva lua te w ithsonognaphy because o f su rround ing bowe l gas and m esen -ten ic fa t. T h is s itua tion is p robab ly fu rthe r w o rsened by theh igh a ttenua tion o f the syn the tic g ra ft w a lls . F o rtuna te ly , longpo rtions o f a ll m esoa tria l shun ts a re eas ily im aged as theypass cepha lad and com e to lie d ire c tly benea th the an ter io r


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AJR :1 54 , Fe bru a ry 199 0 CO LOR DO PPLER OF PO RTOSYSTEM IC SHUNTS 39 7

abdom ina l w a ll. In ou r expe rience , con firm a tion o f flow w ith ineven a sm a ll po rtion o f a m esoa tn ia l (o r m esocava l) shun t issu ffic ie n t to e s ta b lish pa ten cy .

The anastom os is be tw een the sp len ic ve in and le ft rena lve in in W a rre n shun ts a ls o m ay be d iff icu lt to im age . T hesp len ic lim b o f the shun t usua lly can be fo llowed do rsa lly fo ra cons ide rab le d is tance w hen scann ing from a le ft subcos ta lapp roach . Le ft rena l ve in flow , howeve r, is no rm a lly d ire c tedpe rpend icu la r to the sp len ic ve in . D opp le r s igna ls from thele ft re na l v e in , the re fo re , a re b es t re ce iv ed b y s cann in gth rough the le ft fla nk . B ecause im ag ing o f the sp len ic andrena l ve in s is op tim a lly pe rfo rm ed from tw o d iffe ren t van tagepo in ts , th e ana s tom os is m ay be d iff icu lt to im age in a s in g lesec tion . W ith expe rience and m eticu lous techn ique , co lonDopp le r sonog raphy shou ld be capab le o f v isua liz ing theanas tom os is o f pa ten t sp lenonena l shun ts in m os t pa tien ts .W e have found tha t s cann ing the pa tien t w hen the s tom achis em pty is pa rticu la r ly he lp fu l.

In ou r pa tien t w ith a sp leno rena l shun t and ang iognaph ica llyp roved th rom bos is , the ac tua l s ite o f occ lu s ion w as no t seen .T h is is to be expec ted in sp leno rena l shun ts s in ce the wa llso f na tiv e ve in s a re no t su ffic ien tly echogen ic to ou tline theshun t if a co lor s igna l is absen t. T h rom bos is , how eve r, w asin fe rred w hen a tang le o f vesse ls w as found ex tend ing fromthe sp leen to la rge re tropen itonea l co lla te ra ls . Am ong thesevesse ls , the sp len ic lim b o f the shun t cou ld no t be de fined asan ind iv idua l s tru c tu re . The p resence o f shun t dys func tion inth is pa tien t w as pa rticu la r ly obv ious s in ce a rou tine pos top -ena tiv e s tudy 6 weeks ea rlie r show ed the typ ica l s ing le vesse lextend in g from the sp le n ic h ilum to th e le ft rena l ve in . N oco lla tena ls w e re p resen t a t the tim e of the ea rlie r s tudy . T heappea rance o f co lla tena ls in the pa tien t w ith th rom bos is wass im ila r to th a t in the pa tie n t w ith suspe c ted shun t dys fu n c tio nseconda ry to na rrow ing o f the cen tra l le ft rena l ve in . O n thebas is o f these two cases , abno rm a l shun t phys io logy (o ractua l th rom bos is) shou ld be su specte d in any pa tien t w ith asp leno rena l shun t in whom le ft uppe r quad rant co lla tena ls a reiden tifie d in s tead o f a w e ll-de fined sp len ic lim b .

O u r s tudy has found co lo r D opp le r sonog raphy to be anexce llen t non in vas ive m e thod o f im ag ing po rto s ys tem icshun ts o f a ll v a rie tie s . The exam ina tion is w e ll to le ra ted andm ay even be pe rfo rm ed po rtab ly , if necessa ry . W h ile dup lex

scann ing offe rs d iagnos tic in fo rm a tion in m ost pa tien ts w ithpo rtacava l, m esocava l, and m esoa tria l sh un ts , co lon Dopp le rim ag ing is pe rfo rm ed m o re rap id ly , and ana tom ic de linea tiono f shun t ph ys io lo gy inc reases phys ic ia n con fidence . In th eeva lua tion o f sp lenonena l shun ts , how eve r, ou r s tudy show sco lo r D opp le r sonognaphy to be supe rio r to dup lex Dopp le rsonography and the on ly adequa te sonognaph ic m e thod o feva luat ion .

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B u dd -C h ia ri s y nd ro m e . A n n S u rg 1978 ;187 :402 -4064 . S chw a rtz S I, ed . P rin c ip le s o f s u rg e ry , 3d ed . N ew Y ork : M cG ra w-H ill,

1 97 9: 1 297 -1 31 55 . C am eron JL , K ad ir 5 , P ie rce W S . M esoa tria l s hu n t: a p ro s th es is m od if i-

c a t ion . S u r g e r y 1984 ;96 :114 -1166 . A bra hm s H L, ed . A n g i o g r a p h y , 2d e d. B os to n: L itt le , B row n, 1 971 :10 73 -

10787 . G o ldb e rg B B , P a te l J . tJ tra so n ic e va lua t ion o f p o r tacava l shu n ts . JC U1977 ;5 :304 -306

8 . G ley s tee n J J , F o ley W D, Law son TL , Unge r G F. P ate n cy eva lua tio n o fd is ta l sp leno re na l sh un t w ith dyn am ic com pu ted tom og ra phy . S urg G yn e -c ol O bs te t i 982 ; 154 : 689 - 694

9 . F ole y W D, G le ys te en J J , Lawson T L, e t a l. D yn am ic c om pu te d to mo gra ph yand pu lse d D opp le r sonogra phy in th e eva lua tio n o f sp ie no rena l shun tpa tenc y . J C o m pu t A s s is t T o m og r 1983;7 : 106-112

1 0 . B em ard in o M E , S te in be rg HV , P ea rso n TC , G edgaudas-M cC Iee s AK ,Tor r es W E , Hender son JM . S hun ts fo r p orta l h yp er te ns io n: MR anda ng io gra ph y fo r d ete rm in atio n o f p a te n cy . R a d i o l o g y 1986;158 : 57 - 61

11 . A ck ro yd N , G ill A , G riffiths K , K o sso ff G , R eeve T . D up le x s cann in g o f th epo rta l ve in and po rta sys tem ic shu n ts . S u r g e r y 1986;99 : 591 - 597

12 . F inn JP , G ib son A N , D unn GD . D up le x u ltra so und in the e va lu a tio n o fpor tacava l shun ts . C lln R ad io ! 1987 ;38 :87 -89

1 3. F orsb e rg L , H olm in T . P ulse d D opp le r a nd B -m ode u ltra so und fe a tu re s o fin te rpo s ition m eso-cava l an d po rta -ca va l shun ts . A c ta R a d io ! (D ia g n ]( S to c k h) i 9 83 ; 24 : 35 3 -3 5 7

14 . L a fo rtu ne M , P atnqu in H , P om ie r G , e t a l. H em odynam ic changes in p o rta lc ircu la t ion a fte r p o rtosy s tem ic shu n ts : use o f dup le x so nog ra phy in 43pa t ien t s . AJ R i987 ;149 :701 -706

15 . P atriqu in H , L a fo rtun e M , W ebe r A , B lan cha rd H , G are l L , R oy C . S urg ica lpor tos y s temic shun ts in ch ild re n : a sse ssm en t w ith d up le x D opp le r US .R a d i o ! o g y 1987;165 : 25 - 28

1 6. G ran t E G, P erre ila A , T ess le r F N, L ois J , B usu tti l A . B udd -C hia r i syn dro me :th e re su lts o f du plex a nd co lo r D op ple r im ag in g. A JR i 98 9 ;1 5 2 :3 7 7- 38 1

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