CASE REPORT
Pe r sist e n t scia t ic a r t e r y a n e u r ysm : ca se r e por t
José La ce r da Br a sile ir oI, Ju lia n a Ch e nI I, M a ldon a t Az a m bu j a Sa n t osI I I
IMem ber, SBACV. MSc., Univer sidade Feder al de São Paulo - Escola Paulist a de Medicina ( UNI
FESP-EPM) , São Paulo, SP, Br azil. Pr ecept or , Medical Residence in Vascular Sur ger y, Hospit al
Universit ário - Univer sidade Feder al de Mat o Gr osso do Sul ( HU/ UFMS) , Cam po Gr ande, MS, Brazil.
I IResident , Vascular Sur ger y, HU/ UFMS, Cam po Gr ande, MS, Br azil.
I I ICoordinat or, Com m ission for Medical Residence ( COREME) , Cam po Gr ande, MS, Br azil.
Supervisor, Medical Residence in Vascular Sur ger y, HU/ UFMS, Cam po Gr ande, MS, Brazil.
Correspondence
J Vasc Bras. 2008; 7( 1) : 62- 5.
ABSTRACT
The aut hors report a case of per sist ent sciat ic art ery aneur ysm , w hich is a r ar e vascular congenit al disease t hat occurs w hen t he fem or al syst em fails t o develop or w hen t he pr im it ive vascular
syst em fails t o involut e dur ing em br yologic developm ent . A 60- year- old m ale pat ient pr esent ed a painless and pulsat ile but t ock m ass for 4 m ont hs. He had no hist ory of ext er nal t r aum a.
Com plem ent ar y t est s dem onst r at ed an incom plet e and unilat eral per sist ent sciat ic art ery
aneurysm . The pat ient w as subm it t ed t o pr oxim al and dist al ligat ion of sciat ic art ery, and vascular r econst r uct ion w as not per for m ed.
Ke yw or ds:Persist ent sciat ic art ery, aneur ysm , sciat ic art ery.
RESUM O
Os aut or es r elat am um caso de aneur ism a de art éria isquiát ica per sist ent e, um a r ar a doença vascular congênit a ocasionada por falha ou no desenvolvim ent o do sist em a fem or al ou na
Pa la vr a s- ch a ve : Art éria isquiát ica per sist ent e, aneur ism a, ar t ér ia isquiát ica.
I n t r odu ct ion
Persist ent sciat ic art ery is a r ar e congenit al m alfor m at ion, in w hich t he pr im it ive vascular t runk persist s as t he m ain blood supply t o t he low er lim bs. I t can pr ogr ess t o aneur ysm al dilat at ion, as w ell as t o lim b ischem ia due t o t hr om bosis or dist al em bolism , t o local neur om uscular com pr ession or even t o it s r upt ur e.1
Based on t he st udy of sciat ic art ery em br yogenesis, it s per sist ence can be com plet e, t he m ost com m on t ype, in w hich t his art ery cont inues direct ly w it h t he poplit eal art ery and is usually associat ed w it h hypoplasia or absence of fem or al ar t er y, w her e in incom plet e per sist ence t he
sciat ic art ery is hypoplast ic, so t he fem or al syst em is pr evalent .1
Art eriography is r equir ed bot h for diagnosis and st udy of low er lim b art erial cir culat ion, for sur gical planning.
The aut hors report a rare case of left sciat ic art ery per sist ence associat ed w it h aneur ysm .
Ca se r e por t
Doppler ult rasound show ed ar t er ial aneur ysm in t he left but t ock, possibly in t he sciat ic ar t er y, m easur ing 6.4 cm in it s largest diam et er and 7.0 cm long, w it h par iet al t hr om bus occupying a large part of it s lum en; t hat art ery cont inued, aft er t he aneur ysm , in a descending rout e in t he post er ior t high unt il r eaching t he poplit eal art ery at t he k nee level.
Com put ed t om ography revealed a t um or m easur ing 7.7. cm in lengt h, 4.2 cm in t he
ant eropost erior axis and 5.0 cm in w idt h at t he ischior ect al fossa, bet w een t he large fem or al t uberosit y and t he sciat ic br anch, post er ior t o t he superior gem ellus m uscle and pir ifor m and ant erior t o t he glut eus m axim us m uscle, det er m ining ext r insic m uscle com pr ession and especially nerves in t his r egion, such as t he sciat ic, inferior glut eus or post er ior cut aneous of t he t high. I t also show ed int er r upt ed per ipher al lam inar calcificat ions in t he post er ior and lat er al m argin of t he m ass and absence of significant lesion im pr egnat ion aft er use of endovenous cont rast .
Aft er being subm it t ed t o pr eoper at ive exam inat ions and car diologic assessm ent , t he pat ient w as subm it t ed t o open sur gical t r eat m ent , in w hich pr oxim al and dist al ligat ion of t he sciat ic ar t er y w as
perform ed, associat ed w it h opening and leakage of t he aneur ysm al t hr om bus (Figure 3) . Art erial
r econst r uct ion w as not necessar y, because per sist ent sciat ic art ery w as incom plet e.
I n t he post operat ive per iod, t he pat ient progressed unevent fully, being discharged aft er 3 days.
The pat ient is in out pat ient follow- up, w it h r eassessm ent s ever y 6 m ont hs, and is cur r ent ly asym pt om at ic.
Persist ent sciat ic art ery is a r ar e congenit al vascular pat hology, w hose incidence is appr oxim at ely 0.03- 0.06% . Ther e is no prevalence as t o gender , but m ean age is around 51 years, alt hough t he pat ient in t his case w as already 60 year s w hen diagnosis w as per for m ed. I n 1/ 3 of cases, it s locat ion is bilat er al.2 , 3
Dur ing em br yogenesis, t he art ery follow ing t he sciat ic ner ve represent s t he m ain blood supply of t he low er lim bs. As t he fem or al art ery, a cont inuat ion of t he ext er nal iliac ar t er y, is developed t o becom e t he m ain blood supply of t he low er lim b, t here is an involut ion of t hat art ery, w hose rem ainders for m t he poplit eal and fibular art eries. The ot her ar t er ial vessels ar e for m ed fr om t he ext ernal iliac art ery. Failure in developm ent of t he fem or al syst em or in involut ion of t he axial syst em generat es per sist ent sciat ic art ery.1 , 4 , 5
Such lesion can be m anifest ed in t w o for m s: com plet e, t he m ost com m on t ype, in w hich t he persist ent sciat ic art ery r epr esent s t he m ain blood supply t o t he low er lim bs, usually w it h hypoplast ic fem or al ar t er y, w hereas t he ext er nal and com m on fem or al iliac art eries are nor m al; and incom plet e, obser ved in t he present case, in w hich t her e is hypoplasia of t he sciat ic art ery of
t he t high and pr edom inance of t he fem or al syst em .6
Diagnosis is usually perform ed in t he pr esence of com plicat ions, such as pulsat ile but t ock m ass ( aneur ysm ) and/ or associat ed w it h com pr essive sym pt om s of m uscles and ner ves in t hat region ( inferior glut eus, post er ior cut aneous of t he t high and sciat ic) , low er lim b ischem ia ( t hr om bosis and em bolic event s) and rupt ure. I t should be suspect ed in case of absence of fem or al pulse, but w it h
present poplit eal and/ or pedal pulses ( Cow ie's sign) .2 I n our st udy, t he pat ient sought m edical care
present ing pulsat ile but t ock m ass ( aneur ysm ) , w hich caused him local pain, especially w hen sit t ing.
About 25% of cases pr ogr ess t o aneur ysm , pr obably due t o t heir anat om ic posit ion being
suscept ible t o t he t r aum a. Change in elast ic com ponent s of t he art erial w all predisposes bot h for aneurysm al for m at ion and for at her om at ous degener at ion, besides being suggest ed t hat
hyper t ension can also cont ribut e in t he long t erm .7 , 8 I n our case, t he pat ient r epor t ed increased
blood pr essur e since t he m ass w as for m ed, despit e regular use of drugs for hyper t ension.
Recent t raum a hist ory should be invest igat ed t o exclude pseudoaneur ysm , as w ell as fem or al art ery lesion, glut eal art ery aneur ysm and ar t er iovenous fist ulas.
Art eriography is essent ial bot h for diagnosis and for assessm ent of ar t er ial anat om y, classically ident ifying t he int er nal iliac art ery, w hich follow s t he fem or al head lat er ally w it h a diam et er sm aller t han t hat of t he ext ernal iliac art ery, being locat ed post eriorly in t he oblique incidences. The
ext ernal iliac and com m on fem or al ar t er ies are usually nor m al or hypoplast ic. The fem or al art ery is gradually narrow ed as it m oves t ow ar d t he t high and is bifurcat ed close t o t he adduct or canal level. Near t he nar r ow ing, t he sciat ic art ery is t ort uous, usually ect at ic and w it h ir r egular w alls. Dist al
vessels can be nor m al or have signs of at herosclerosis.9 , 1 0
Com put ed t om ography and m agnet ic resonance allow det er m ining act ual size and adj acent
st ruct ures.7 Doppler ult rasound is consider ed a useful inst r um ent , since it allow s t r acking t he
course of vessels and locat e r egions of significant t urbulence, w hich m ay r epr esent pr esence of
aneurysm .2 Angiographic com put ed t om ogr aphy provides good assessm ent of t he pelvic vascular
syst em , and is considered bet t er t han ult r asound t o assess abdom inal aort ic aneur ysm s, but
equivalent t o angiogr aphy t o t he vascular st udy of m edium - and large- sized art eries.1 1
recom m ended. That w as t he conduct used in t his case, besides opening and aneurysm al sac explor at ion in sear ch of addit ional feeding vessels. How ever , in it s com plet e for m , low er lim b
revascularizat ion is r ecom m ended, associat ed w it h exclusion.8 , 1 2 Bez et al.1 3 r epor t ed a case in
w hich t he sciat ic art ery w as com plet ely aneurysm al unt il t he poplit eal ar t er y, w hich r equir ed surgical t reat m ent w it h fem or ofibular revascularizat ion using t he saphenous vein associat ed w it h sciat ic art ery ligat ion.
Revascularizat ion can be perform ed by fem or opoplit eal or t r ansobt ur at or iliac- poplit eal bypass. The fem oropoplit eal t echnique is not indicat ed in cases in w hich t he hypoplast ic fem or al syst em does
not pr ovide proper blood flow . How ever , Eglint on et al.5 consider t r ansobt ur at or bypass a good
opt ion in t hese cases, since it allow s a short er r out e for t he bypass.
Wit h t he developm ent of endovascular t echniques, t her e are new m et hods for t he t r eat m ent of
persist ent sciat ic art ery aneur ysm s offer ing low er risk of lesion in t he nerves of t hat ar ea.1 2
Gabelm ann et al.1 4 and Fear ing et al.6 r epor t ed good out com es w it h t he use of endovascular st en t
aft er follow ing t heir cases for 22 and 39 m ont hs, r espect ively. How ever , out com e dur abilit y requires fur t her st udies w it h longer observat ion t im e.
Re fe r e n ce s
1. Cot t a- Pereira G. Em br iologia e hist ór ia do sist em a vascular . I n: Br it o CJ, Duque A, Mer lo R, Lauria Filho V, edit or s. Cir ur gia vascular . Rio de Janeiro: Revint er ; 2002. p. 11- 23.
2. Mayschak DT, Flye MW. Treat m ent of t he per sist ent sciat ic ar t er y. Ann Surg. 1984; 199: 69- 74.
3. Hassan A. Sym pt om at ic per sist ent sciat ic ar t er y. J Am Coll Surg. 2004; 199: 171- 3.
4. Par r y DJ, Aldoori MI , Ham m ond RJ, Kessel DO, West on M, Scot t DJ. Persist ent sciat ic vessels,
varicose veins, and low er lim b hyper t r ophy: an unusual case or discret e clinical syndr om e?J Vasc
Surg. 2002; 36: 396- 400.
5. Eglint on TW, Gor don MK. Persist ent sciat ic art ery aneurysm t reat ed by exclusion and obt ur at or bypass. EJVES Ext ra. 2005; 29: 29- 31.
6. Fear ing NM, Am m ar AD, Hut chinson SA, Lucas ED. Endovascular st ent gr aft r epair of a
persist ent sciat ic art ery aneur ysm. Ann Vasc Sur g. 2005; 19: 438- 41.
7. de Boer MT, Ev ans JD, Mayor P, Guy AJ. An aneurysm at t he back of a t high: a r ar e present at ion of a congenit ally per sist ent sciat ic ar t er y. Eur J Vasc Endovasc Sur g. 2000; 19: 99- 100.
8. Bat chelor TJ, Vow den P. A per sist ent sciat ic art ery aneurysm w it h an associat ed int er nal iliac art ery aneurysm. Eur J Vasc Endovasc Sur g. 2000; 20: 400- 2.
9. Sam son RH, Show alt er DP. Persist ent sciat ic art ery as collat er al for an occluded iliofem or al syst em. J Vasc Surg. 2004; 40: 183.
10. Mandell VS, Jaques PF, Delany DJ, Ober heu V. Persist ent sciat ic ar t er y: clinical, em br yologic, and angiographic feat ures. AJR Am J Roent genol. 1985; 144: 245- 9.
12. Jain S, Munn JS, Sim oni EJ, Jain KM. Endograft r epair of a per sist ent sciat ic art ery aneur ism. EJVES Ext r a. 2004; 8: 5- 6.
13. Bez LG, Cost a- Val R, Bast ianet t o P, et al. Persist ência da ar t ér ia isquiát ica: r elat o de caso. J Vasc Bras. 2006; 5: 233- 6.
14. Gabelm ann A, Kräm er SC, Wisianow ski C, Tom czak R, Pam ler R, Gör ich J. Endovascular int ervent ions on per sist ent sciat ic art eries. J Endovasc Ther. 2001; 8: 622- 8.
Cor r e spon de n ce :
José Lacer da Brasileiro
Rua Gonçalo Alves, 59, Vivendas do Bosque CEP 79021- 182 - Cam po Gr ande, MS
Tel.: ( 67) 8142.2314, ( 67) 3325.559, ( 67) 3326.2842 Em ail: j lbrasileiro@gm ail.com
This st udy w as carried out at t he Vascular Sur ger y Ser vice, HU/ UFMS, Cam po Gr ande, MS, Br azil.
