LETTERS TO THE EDITOR Retrograde Popliteal Endovascular StentGraft Repair for a Growing Persistent Sciatic Artery Aneurysm (Type IIa): Case Report and Review of the Literature From: Hirotatsu Sato, MD Motoki Nakai, MD Morio Sato, MD Akira Ikoma, MD Yoshiharu Nishimura, MD Departments of Radiology (H.S., M.N., M.S., A.I.) and Thoracic and Cardiovascular Surgery (Y.N.) Wakayama Medical University 811-1, Kimiidera Wakayama 641-8510, Japan
Editor: The sciatic artery, connecting the internal iliac artery to the femoral artery, is the main blood route to the lower extremity in the early-stage embryo. This vessel degenerates and disappears with the development of the external iliac artery to the superficial femoral artery (SFA) (1,2). A persistent sciatic artery (PSA) is a postnatal remnant that occurs with an incidence of 0.01%–0.06% (1,2). It is classified into two types: the complete type, in which the lower extremity obtains blood flow predominantly from the sciatic artery; and the incomplete type, in which the popliteal artery obtains blood flow from the SFA (3). Among all PSAs, the complete type is reported to occur with an incidence of 63%–79% (1,4). According to the classification of PSA, PSA combined with an incompletely developed small SFA is classified as type IIa (5,6). We present a patient with an aneurysm of the complete (ie, type IIa) PSA that was treated with endovascular stent-graft repair. Preparation of this retrospective case report was exempted from institutional review board approval. A 75-year-old woman had undergone a left nephrectomy for renal-cell carcinoma 4 years earlier. Although she was asymptomatic, the patient underwent follow-up computed tomography (CT) to check for recurrence. A dense soft-tissue mass 40 mm in diameter was found in her right buttock. A CT scan obtained 1 year later revealed that the mass had increased in diameter to 50 mm. The patient was diagnosed with a right completetype (ie, type IIa) PSA aneurysm based on the contrastenhanced CT findings (Fig 1). Physical examination revealed a pulsatile mass in the right buttock. The ankle-brachial indices on the right and left were 1.12
None of the authors have identified a conflict of interest. http://dx.doi.org/10.1016/j.jvir.2014.08.020
and 1.17, respectively. Laboratory tests showed no abnormal findings. The treatment strategy was created based on measurement of the right-sided aneurysm on contrast-enhanced CT. The length of the aneurysm was 105 mm, the diameter of the proximal landing zone vessel was 13–14 mm, and the diameter of the distal landing zone vessel was 12–13 mm (Fig 2). The patient received epidural anesthesia. With a left femoral artery approach and the patient in the supine position, pelvic arteriography was performed via a 3-F pigtail catheter (Medikit, Miyazaki, Japan); after exchanging the pigtail catheter for a preshaped catheter (3-F RC2; Medikit), selective right internal iliac arteriography was performed to confirm the presence of a right-sided PSA aneurysm. The patient was then moved into the prone position. The right popliteal artery was surgically exposed and an 18-F dry-seal sheath (W.L. Gore and Associates, Flagstaff, Arizona) was inserted with the use of a stiff guidewire (Amplatz Super Stiff Guide Wire, Boston Scientific, Natick, Massachusetts) from the right popliteal artery. Selective right internal iliac arteriography was used to measure the length of the aneurysm (Fig 3a). Two stent-graft placements were scheduled. The first stent graft (EXCLUDER contra-leg device, 16–14.5 mm in diameter/14 cm long; W.L. Gore and Associates) was
Figure 1. Volume-rendered contrast-enhanced CT in posterior–anterior view shows a right complete-type sciatic artery aneurysm.
1998
’
Letters to the Editor
Sato et al
’
JVIR
Figure 2. The diameter and length of the aneurysm were measured with contrast-enhanced CT. Based on these measurements, two overlapping stent grafts (1 and 2) were used.
Figure 3. Selective internal iliac arteriography before (a) and immediately after (b) stent-graft placement shows no evidence of leakage.
deployed before the second (EXCLUDER contra-leg device, 16–18 mm in diameter/13.5 cm long; W.L. Gore and Associates) was deployed from the proximal landing zone to the inside of the aneurysm, overlapping the first stent graft by approximately 7 cm. Both stent-grafts were then inflated with a Coda balloon catheter (32 mm/ 100 cm; Cook, Bloomington, Indiana). Angiography performed immediately after stent-graft deployment showed no endoleak (Fig 3b). Figure 4 shows that
there was no compression of the stent graft when the patient was in an upright or sitting position. The patient was discharged on postsurgical day 4. Thereafter, oral antiplatelet clopidogrel was administered continuously. Contrast-enhanced CT 12 months after intervention showed that the PSA aneurysm had shrunk, with no evidence of an endoleak and good runoff to the lower extremity, and no apparent flexure or fracture of the stent graft (Fig 5).
Volume 25
’
Number 12
’
December
’
2014
1999
Figure 4. Radiographs with the patient in the upright (a) and sitting (b) positions show no flexure or compression of the stent graft.
Figure 5. Contrast-enhanced CT 12 months after treatment shows no evidence of endoleak, and the aneurysm diameter has decreased from 50 mm to 40 mm. No flexure or fracture of the stent graft is apparent.
The native PSA aneurysm may partially thrombose and then embolize clot in the lower extremity. Rupture and/or embolization of PSA aneurysms have been reported, and can cause sciatic nerve disorder (1). The treatment of sciatic artery aneurysms depends on the symptoms present and the classification type.
Surgical resection, coil embolization, and endovascular stent-graft repair are listed as the treatment options (1). Surgical treatment requires two procedures, surgical aneurysm removal and bypass intervention. Surgical removal of the aneurysm entails a risk of sciatic nerve injury (1). Coil embolization may be performed for aneurysms in incomplete-type PSA if the collateral (or SFA) supply is sufficient. However, for complete-type PSA, endovascular stent-graft repair may be appropriate. All 10 previously reported patients who underwent stent-graft repair had a complete-type PSA (Table). The advantage of this procedure is that the aneurysm can be eradicated and the vascularity reconstructed simultaneously, with no risk of sciatic nerve injury (1). In addition, it is applicable to patients with high-risk factors for surgical repair. Six of the previous cases had been treated via the contralateral femoral artery and the other four via the ipsilateral popliteal artery (Table) (7–16). We used the ipsilateral popliteal artery approach in our patient because the 18-F sheath is large, and achieved a satisfactory outcome. A possible limitation of endovascular stent-graft repair is the unknown durability of the stent graft. To reinforce the strength and durability of the stent grafts, we overlapped them. In the present case, the stent graft remains patent, with no fracture or occlusion, at 1 year since implantation. In the nine previous reports, the durability of the stent graft, without problems, was reported to be 4 years at most. However, in the most recent report (9), the stent graft fractured 6 months after implantation. Therefore, longer follow-up periods and greater numbers of patients must be investigated to ensure the long-term patency and durability of the stent graft.
2000
’
Letters to the Editor
Sato et al
’
JVIR
Table . Reported Cases of Persistent Complete (Type IIa) Sciatic Artery Aneurysm Treated with a Stent Graft (7–16) Stent Graft Aneurysm Size (mm)
Sheath Size (F)
Device
Pieces
Diameter Length (mm)
Follow-up (mo)
CF
NS
NS
HEMOBAHN
1
10 60
22
NS
IP
35
NS
Wallgraft
1
NS 100
3
NS
IP
65
9
AneuRx
1
12 115
39
F
NS
IP
35
NS
VIABAHN
1
6 150
48
57
M
I
CF
26
8
VIABAHN
2
8 5*, 7 5*
6
70
M
NS
CF
44
NS
VIABAHN
1
8 150
6
Debels et al (14), 2011
47
F
NS
CF
NS
12
Hemobahn
2
11 110
1
Shibutani et al (15),
74
F
NS
CF
36
9
Fluency
1
10 80
6
2013 Nuño-Escobar et al
53
M
NS
CF
70
NS
HEMOBAHN
2
10 50
6
Girsowicz et al (9), 2014
65
M
NS
IP
24
12
VIABAHN
1
11 110
6 F1(þ)
Present case
75
F
IIa
IP
50
18
EXCLUDER
2
16–14.5 140,
12
Patient Age (y)
Sex
Gabelmann et al (10), 2001
63
F
NS
Jain et al (11), 2004
83
M
Fearing et al (12), 2005
88
F
Wijeyaratne et al
55
(13), 2009 Verikokos et al (8),
Study, Year
Class Access
2010 Mascarenhas de Oliveira et al (7), 2011
(16), 2013
16–18 135 CF ¼ contralateral femoral, F1 ¼ fracture of the stent graft, IP ¼ ipsilateral popliteal, NS ¼ not specified. *The length of 5 mm in the manuscript is probably incorrect.
In conclusion, although stent grafts have limited long-term durability, endovascular stent-graft repair performed to eradicate sciatic artery aneurysm achieved good runoff to the lower extremity for 12 months, with minimum invasion and no risk of sciatic nerve injury.
REFERENCES 1. van Hooft IM, Zeebregts CJ, van Sterkenburg SM, de Vries WR, Reijnen MM. The persistent sciatic artery. Eur J Vasc Endovasc Surg 2009; 37: 585–591. 2. Brantley SK, Rigdon EE, Raju S. Persistent sciatic artery: embryology, pathology, and treatment. J Vasc Surg 1993; 18:242–248. 3. Bower EB, Smullens SN, Parke WW. Clinical aspects of persistent sciatic artery: report of two cases and review of the literature. Surgery 1977; 81:588–595. 4. Martin KW, Hyde GL, McCready RA, Hull DA. Sciatic artery aneurysms: report of three cases and review of the literature. J Vasc Surg 1986; 4: 365–371. 5. Pillet J, Cronier P, Mercier PH, Chevalier JM. The ischiopopliteal arterial trunk: a report of two cases. Anat Clin 1982; 3:329–331. 6. Gauffre S, Lasjaunias P, Zerah M. Sciatic artery: a case, review of literature and attempt of systemization. Surg Radiol Anat 1994; 16: 105–109.
7. Mascarenhas de, Oliveira F, de Souza Mourão G. Endovascular repair of symptomatic sciatic artery aneurysm. Vasc Endovasc Surg 2011; 45: 165–169. 8. Verikokos C, Avgerinos ED, Chatziioannou A, Katsargyris A, Klonaris C. Endovascular repair of a persistent sciatic artery aneurysm. Vascular 2010; 18:162–165. 9. Girsowicz E, Georg Y, Lejay A, et al. Midterm failure after endovascular treatment of a persistent sciatic artery aneurysm. Ann Vasc Surg 2014; 28(1323):e7–e12. 10. Gabelmann A, Krämer SC, Wisianowski C, Tomczak R, Pamler R, Görich J. Endovascular interventions on persistent sciatic arteries. J Endovasc Ther 2001; 8:622–628. 11. Jain S, Munn JS, Simoni EJ, Jain KM. Endograft repair of a persistent sciatic artery aneurysm. Eur J Vasc Surg Extro 2004; 8:5–6. 12. Fearing NM, Ammar AD, Hutchinson SA, Lucas ED. Endovascular stent graft repair of a persistent sciatic artery aneurysm. Ann Vasc Surg 2005; 19:438–441. 13. Wijeyaratne SM, Wijewardene N. Endovascular stenting of a persistent sciatic artery aneurysm via retrograde popliteal approach: a durable option. Eur J Vasc Endovasc Surg 2009; 38:91–92. 14. Debels H, De Gendt G. Persistent sciatic artery aneurysm: a case report. Acta Chir Belg 2011; 111:256–259. 15. Shibutani S, Hayashi E, Obara H, et al. Rapid development of aneurysmal formation after successful endovascular treatment of chronic total occlusion of a persistent sciatic artery. Ann Vasc Surg 2013; 27: 499e5–499e8. 16. Nuño-Escobar C, Pérez Durán MA, Ramos-López R, et al. Persistent sciatic artery aneurysm. Ann Vasc Surg 2013; 27:1182e13–1182e16.
Editor: The sciatic artery, connecting the internal iliac artery to the femoral artery, is the main blood route to the lower extremity in the early-stage embryo. This vessel degenerates and disappears with the development of the external iliac artery to the superficial femoral artery (SFA) (1,2). A persistent sciatic artery (PSA) is a postnatal remnant that occurs with an incidence of 0.01%–0.06% (1,2). It is classified into two types: the complete type, in which the lower extremity obtains blood flow predominantly from the sciatic artery; and the incomplete type, in which the popliteal artery obtains blood flow from the SFA (3). Among all PSAs, the complete type is reported to occur with an incidence of 63%–79% (1,4). According to the classification of PSA, PSA combined with an incompletely developed small SFA is classified as type IIa (5,6). We present a patient with an aneurysm of the complete (ie, type IIa) PSA that was treated with endovascular stent-graft repair. Preparation of this retrospective case report was exempted from institutional review board approval. A 75-year-old woman had undergone a left nephrectomy for renal-cell carcinoma 4 years earlier. Although she was asymptomatic, the patient underwent follow-up computed tomography (CT) to check for recurrence. A dense soft-tissue mass 40 mm in diameter was found in her right buttock. A CT scan obtained 1 year later revealed that the mass had increased in diameter to 50 mm. The patient was diagnosed with a right completetype (ie, type IIa) PSA aneurysm based on the contrastenhanced CT findings (Fig 1). Physical examination revealed a pulsatile mass in the right buttock. The ankle-brachial indices on the right and left were 1.12
None of the authors have identified a conflict of interest. http://dx.doi.org/10.1016/j.jvir.2014.08.020
and 1.17, respectively. Laboratory tests showed no abnormal findings. The treatment strategy was created based on measurement of the right-sided aneurysm on contrast-enhanced CT. The length of the aneurysm was 105 mm, the diameter of the proximal landing zone vessel was 13–14 mm, and the diameter of the distal landing zone vessel was 12–13 mm (Fig 2). The patient received epidural anesthesia. With a left femoral artery approach and the patient in the supine position, pelvic arteriography was performed via a 3-F pigtail catheter (Medikit, Miyazaki, Japan); after exchanging the pigtail catheter for a preshaped catheter (3-F RC2; Medikit), selective right internal iliac arteriography was performed to confirm the presence of a right-sided PSA aneurysm. The patient was then moved into the prone position. The right popliteal artery was surgically exposed and an 18-F dry-seal sheath (W.L. Gore and Associates, Flagstaff, Arizona) was inserted with the use of a stiff guidewire (Amplatz Super Stiff Guide Wire, Boston Scientific, Natick, Massachusetts) from the right popliteal artery. Selective right internal iliac arteriography was used to measure the length of the aneurysm (Fig 3a). Two stent-graft placements were scheduled. The first stent graft (EXCLUDER contra-leg device, 16–14.5 mm in diameter/14 cm long; W.L. Gore and Associates) was
Figure 1. Volume-rendered contrast-enhanced CT in posterior–anterior view shows a right complete-type sciatic artery aneurysm.
1998
’
Letters to the Editor
Sato et al
’
JVIR
Figure 2. The diameter and length of the aneurysm were measured with contrast-enhanced CT. Based on these measurements, two overlapping stent grafts (1 and 2) were used.
Figure 3. Selective internal iliac arteriography before (a) and immediately after (b) stent-graft placement shows no evidence of leakage.
deployed before the second (EXCLUDER contra-leg device, 16–18 mm in diameter/13.5 cm long; W.L. Gore and Associates) was deployed from the proximal landing zone to the inside of the aneurysm, overlapping the first stent graft by approximately 7 cm. Both stent-grafts were then inflated with a Coda balloon catheter (32 mm/ 100 cm; Cook, Bloomington, Indiana). Angiography performed immediately after stent-graft deployment showed no endoleak (Fig 3b). Figure 4 shows that
there was no compression of the stent graft when the patient was in an upright or sitting position. The patient was discharged on postsurgical day 4. Thereafter, oral antiplatelet clopidogrel was administered continuously. Contrast-enhanced CT 12 months after intervention showed that the PSA aneurysm had shrunk, with no evidence of an endoleak and good runoff to the lower extremity, and no apparent flexure or fracture of the stent graft (Fig 5).
Volume 25
’
Number 12
’
December
’
2014
1999
Figure 4. Radiographs with the patient in the upright (a) and sitting (b) positions show no flexure or compression of the stent graft.
Figure 5. Contrast-enhanced CT 12 months after treatment shows no evidence of endoleak, and the aneurysm diameter has decreased from 50 mm to 40 mm. No flexure or fracture of the stent graft is apparent.
The native PSA aneurysm may partially thrombose and then embolize clot in the lower extremity. Rupture and/or embolization of PSA aneurysms have been reported, and can cause sciatic nerve disorder (1). The treatment of sciatic artery aneurysms depends on the symptoms present and the classification type.
Surgical resection, coil embolization, and endovascular stent-graft repair are listed as the treatment options (1). Surgical treatment requires two procedures, surgical aneurysm removal and bypass intervention. Surgical removal of the aneurysm entails a risk of sciatic nerve injury (1). Coil embolization may be performed for aneurysms in incomplete-type PSA if the collateral (or SFA) supply is sufficient. However, for complete-type PSA, endovascular stent-graft repair may be appropriate. All 10 previously reported patients who underwent stent-graft repair had a complete-type PSA (Table). The advantage of this procedure is that the aneurysm can be eradicated and the vascularity reconstructed simultaneously, with no risk of sciatic nerve injury (1). In addition, it is applicable to patients with high-risk factors for surgical repair. Six of the previous cases had been treated via the contralateral femoral artery and the other four via the ipsilateral popliteal artery (Table) (7–16). We used the ipsilateral popliteal artery approach in our patient because the 18-F sheath is large, and achieved a satisfactory outcome. A possible limitation of endovascular stent-graft repair is the unknown durability of the stent graft. To reinforce the strength and durability of the stent grafts, we overlapped them. In the present case, the stent graft remains patent, with no fracture or occlusion, at 1 year since implantation. In the nine previous reports, the durability of the stent graft, without problems, was reported to be 4 years at most. However, in the most recent report (9), the stent graft fractured 6 months after implantation. Therefore, longer follow-up periods and greater numbers of patients must be investigated to ensure the long-term patency and durability of the stent graft.
2000
’
Letters to the Editor
Sato et al
’
JVIR
Table . Reported Cases of Persistent Complete (Type IIa) Sciatic Artery Aneurysm Treated with a Stent Graft (7–16) Stent Graft Aneurysm Size (mm)
Sheath Size (F)
Device
Pieces
Diameter Length (mm)
Follow-up (mo)
CF
NS
NS
HEMOBAHN
1
10 60
22
NS
IP
35
NS
Wallgraft
1
NS 100
3
NS
IP
65
9
AneuRx
1
12 115
39
F
NS
IP
35
NS
VIABAHN
1
6 150
48
57
M
I
CF
26
8
VIABAHN
2
8 5*, 7 5*
6
70
M
NS
CF
44
NS
VIABAHN
1
8 150
6
Debels et al (14), 2011
47
F
NS
CF
NS
12
Hemobahn
2
11 110
1
Shibutani et al (15),
74
F
NS
CF
36
9
Fluency
1
10 80
6
2013 Nuño-Escobar et al
53
M
NS
CF
70
NS
HEMOBAHN
2
10 50
6
Girsowicz et al (9), 2014
65
M
NS
IP
24
12
VIABAHN
1
11 110
6 F1(þ)
Present case
75
F
IIa
IP
50
18
EXCLUDER
2
16–14.5 140,
12
Patient Age (y)
Sex
Gabelmann et al (10), 2001
63
F
NS
Jain et al (11), 2004
83
M
Fearing et al (12), 2005
88
F
Wijeyaratne et al
55
(13), 2009 Verikokos et al (8),
Study, Year
Class Access
2010 Mascarenhas de Oliveira et al (7), 2011
(16), 2013
16–18 135 CF ¼ contralateral femoral, F1 ¼ fracture of the stent graft, IP ¼ ipsilateral popliteal, NS ¼ not specified. *The length of 5 mm in the manuscript is probably incorrect.
In conclusion, although stent grafts have limited long-term durability, endovascular stent-graft repair performed to eradicate sciatic artery aneurysm achieved good runoff to the lower extremity for 12 months, with minimum invasion and no risk of sciatic nerve injury.
REFERENCES 1. van Hooft IM, Zeebregts CJ, van Sterkenburg SM, de Vries WR, Reijnen MM. The persistent sciatic artery. Eur J Vasc Endovasc Surg 2009; 37: 585–591. 2. Brantley SK, Rigdon EE, Raju S. Persistent sciatic artery: embryology, pathology, and treatment. J Vasc Surg 1993; 18:242–248. 3. Bower EB, Smullens SN, Parke WW. Clinical aspects of persistent sciatic artery: report of two cases and review of the literature. Surgery 1977; 81:588–595. 4. Martin KW, Hyde GL, McCready RA, Hull DA. Sciatic artery aneurysms: report of three cases and review of the literature. J Vasc Surg 1986; 4: 365–371. 5. Pillet J, Cronier P, Mercier PH, Chevalier JM. The ischiopopliteal arterial trunk: a report of two cases. Anat Clin 1982; 3:329–331. 6. Gauffre S, Lasjaunias P, Zerah M. Sciatic artery: a case, review of literature and attempt of systemization. Surg Radiol Anat 1994; 16: 105–109.
7. Mascarenhas de, Oliveira F, de Souza Mourão G. Endovascular repair of symptomatic sciatic artery aneurysm. Vasc Endovasc Surg 2011; 45: 165–169. 8. Verikokos C, Avgerinos ED, Chatziioannou A, Katsargyris A, Klonaris C. Endovascular repair of a persistent sciatic artery aneurysm. Vascular 2010; 18:162–165. 9. Girsowicz E, Georg Y, Lejay A, et al. Midterm failure after endovascular treatment of a persistent sciatic artery aneurysm. Ann Vasc Surg 2014; 28(1323):e7–e12. 10. Gabelmann A, Krämer SC, Wisianowski C, Tomczak R, Pamler R, Görich J. Endovascular interventions on persistent sciatic arteries. J Endovasc Ther 2001; 8:622–628. 11. Jain S, Munn JS, Simoni EJ, Jain KM. Endograft repair of a persistent sciatic artery aneurysm. Eur J Vasc Surg Extro 2004; 8:5–6. 12. Fearing NM, Ammar AD, Hutchinson SA, Lucas ED. Endovascular stent graft repair of a persistent sciatic artery aneurysm. Ann Vasc Surg 2005; 19:438–441. 13. Wijeyaratne SM, Wijewardene N. Endovascular stenting of a persistent sciatic artery aneurysm via retrograde popliteal approach: a durable option. Eur J Vasc Endovasc Surg 2009; 38:91–92. 14. Debels H, De Gendt G. Persistent sciatic artery aneurysm: a case report. Acta Chir Belg 2011; 111:256–259. 15. Shibutani S, Hayashi E, Obara H, et al. Rapid development of aneurysmal formation after successful endovascular treatment of chronic total occlusion of a persistent sciatic artery. Ann Vasc Surg 2013; 27: 499e5–499e8. 16. Nuño-Escobar C, Pérez Durán MA, Ramos-López R, et al. Persistent sciatic artery aneurysm. Ann Vasc Surg 2013; 27:1182e13–1182e16.
