1. Strategy of Endovascular management of Post-irradiated Carotid Blowout Syndrome
Dep. of Radiology, Taipei Veterans General Hospital &
National Yang Ming University, School of Medicine
Taipei, Taiwan (Republic of China)
Feng-Chi Chang; Chao-Bao Luo;
Chung-Jung Lin; Han-Jui Lee; Wan-Yuo Guo

2. Contents: Endovascular Tx of Post-irradiated carotid blowout syndrome (PCBS)
1. Introduction
2. Strategy of Endovascular Tx of PCBS
A. A modified classification: ongoing vs acute
B. Imaging diagnosis & F/U: Vascular & soft tissue
lesions
C. Endovascular management:
(1). Techniques and Outcomes
(2). Complications & prevention
3. Conclusion

3. No Head & neck cancers included
1. Introduction: common cancers in Western country
The 10 Most Common Cancers in UK: 2013
Numbers of Cases, Males, UK
No Head & neck cancers included
Source: cruk.org/cancerstats
You are welcome to reuse this Cancer Research UK statistics content for your own work. Credit us as authors by referencing
Cancer Research UK as the primary source. Suggested style: Cancer Research UK, full URL of the page, Accessed [month] [year].

4. Common cancers in Eastern country: Ten most common cancers in Taiwan
Head & neck cancers are very common!

5. Post-irradiated Carotid Blowout Syndrome (PCBS)
PCBS: symptoms associated with rupture of carotid arteries in the patients of head-and-neck cancers accepted irradiation
About 4.3% of patients of head-and-neck cancers
Risk factors: radiation-induced necrosis, recurrent tumors, wound complications, or pharyngocutaneous fistulas
Surgical ligation: 60% morbidity and 40% mortality
Chaloupka JC, 1995 AJNR

6. Blood supply of carotid artery
About 80% blood supply of the carotid wall comes from its adventia (vasa vasorum, arrows).
Soft tissue injury located adjacent to the carotid adventia can cause ischemic insult to the vascular wall.

7. 2. Strategy of endovascular management of PCBS
Ongoing
CT / CTA
Soft tissue lesions
Wound care / skin graft surgery / tumor treatment
Progression
Regression
Follow up
Vascular lesions
Angiogram
( - )
( + )
Trunk
Occlusion test
Failed / Inconclusive
Stent-graft
Ongoing CBS：adjuvant procedure (bypass surgery)
Passed
Branch
Embolization
Acute
Retained femoral sheath for 1 day
A. A modified classification
B. preprocedural
Imaging diagnosis
Bleeding
D. Aggressive
clinical management
C. Embolization as
the prior therapy
E. Aggressive management
of complications
Tx of complications
Dash line: indicates close follow-up after initial management.
Revision from Chang FC, 2015 PLoS One

8. A. Previous Classification of PCBS: By clinical severity
A modified classification
A. Previous Classification of PCBS: By clinical severity
1. Threatened: minimal sentinel bleeding/
exposure of carotid artery
2. Impending: controllable episodes of hemorrhage
3. Acute: uncontrollable bleeding/ unstable vital signs
Limitation: When to perform the endovascular Tx??
Chaloupka JC, 1996 AJNR

9. Modified classification of PCBS By clinical emergency
2 categories:
1. Ongoing PCBS: non-emergent/ controllable
bleeding episodes (threatened + impending
CBS)
2. Acute PCBS: emergent status/
uncontrollable bleeding or hypovolemic
status (acute CBS)
Chang FC, 2015 PLoS One

10. Angiographic severity (grading) of carotid injury: Slight (grade 1 & 2) vs Advanced (grade 3 & 4)
Grade 1= normal/no bulging lesion/increased vascular brushes (arrow, the carotid artery influenced by the diseased soft tissue lesion)
Grade 2= focal irregularity (arrows, by focal weakening of the vascular wall)
Grade 3= pseudoaneurysm/focal bulging (arrow, by vascular rupture confined by the adjacent soft tissue)
Grade 4= active extravasation (arrows, by complete rupture of vascular wall)
Chang FC, J Vasc Surg & 2013 Clin Radiol

11. Good correlation of the modified classification of PCBS (Ongoing & Acute) with the angiographic severity 96 patients of PCBS
Number of patient
P <0.0001
Angiographic severity
** Reasons of this modified classification:
A. correlate well with angiographic severity: P<0.0001
B. can guide the therapeutic planning:
a. Acute: emergent angiogram
b. Ongoing: non-emergent planning, such as a pre-procedural CTA
** If acute or ongoing PCBS was hard to determine or access clinically:
Treat it as “acute PCBS”.
Chang FC, PLoS One

12. Modified classification of PCBS: By clinical emergency
1. Ongoing: non-emergent status 2. Acute: emergent status (uncontrollable bleeding)
When to take endovascular Tx?
Ongoing: CTA
Acute: Angiogram
Chang FC, 2015 PLoS One

13. a). Active extravasation/ pseudoaneurysm
B (1). Preprocedural imaging diagnosis of PCBS: CT/CTA 1. Vascular lesions
Vascular lesions: the pathological lesions of the carotid artery and its branches
Vascular lesions on CT/CTA: suggest an angiogram needed.
3 major CT findings:
a). Active extravasation/ pseudoaneurysm
b). Loss of round shape of the diseased carotid
artery on axial image
c). Displacement of the diseased carotid artery
toward the soft tissue lesion

14. a). Pseudoaneurysm/ ExtravasationB
Ongoing PCBS. A pseudoaneurysm from the trunk of LT ECA (A & B, arrow) was noted in angiogram and CT.
** Presence of pseudoaneurysm or extravasation is
pathognomonic for PCBS but is not conspicuous when the
lesions located in the branches of ECA.
** Note: An angiogram is suggested.

15. b). Loss of axial round shape of the diseased carotid artery
Ongoing PCBS, a grade 3 lesion on the angiogram (A, arrowhead). The right carotid bulb was located adjacent to a skin wound and showed ovoid shape (B, arrowhead) on axial scan of CT 1 week before the angiogram. The contralateral carotid bulb (B, arrow) was round on axial scan.
Explanation: focal weakening of the diseased vascular wall

16. c). Displacement of the diseased carotid artery toward the soft tissue lesionsB
Acute PCBS, CTA 3 days before the angiogram. The left carotid artery was ventrally and laterally displaced toward the necrotic soft tissue wound (B, arrow). Note the distance of left transverse process of C spine and the left CCA is longer than the right side (red lines). Loss of axial round shape of the left carotid artery was also found (B, arrow).
Explanation: loss of focal soft tissue support of the diseased artery

17. B (2). Preprocedural imaging diagnosis of PCBS: CT/CTA B
B (2). Preprocedural imaging diagnosis of PCBS: CT/CTA B. Soft tissue lesions
Soft tissue injury or necrotic tumor adjacent to the diseased carotid artery
Close F/U CT/CTA : post-irradiated soft tissue lesions can have dynamic change.
CT/CTA is better than MRI: MRI has its limitation in detecting the tiny gaseous lesions.
3 major CT findings:
A). Soft tissue necrosis: fluid/gas collection
B). Soft tissue defect: sinus tract/fistula
C). Recurrent necrotic tumors with encasement of
carotid artery

18. a). Adjacent soft tissue necrosis: Fluid/gas collectionB
Acute PCBS & grade 3 lesion on angiogram (A, arrow). CT 1 week before the angiogram showed a focal soft tissue necrosis (B, arrowhead) adjacent to the stenotic left ICA (B, arrow).
Cause ischemic insult to the carotid wall.

19. b). Soft tissue defect: Sinus tract/Fistula/Wound
Ongoing PCBS. CT 1 week before the angiogram showed the right carotid bulb expose to a focal skin wound (B, arrowheads) and lose its axial round shape (B, arrow).
The pharyngocutanous fistula is basically a clinical term. It is sometime difficult to diagnose on CT if no gas collection.

20. c). Recurrent necrotic tumors with encasement of carotid arteryB
Acute PCBS and a grade 4 lesion on angiogram (A, arrow). CTA 3 weeks before the angiogram showed the left carotid artery was encased by large recurrent tumors, including the trunk of left ECA (B, arrow).
Recurrent tumors and the associated repeated surgery and
chemoradiotherapy can further deprive the blood supply of
the carotid wall. This is especially conspicuous when the
tumors become necrotic.

21. C. Endovascular Management of PCBS and outcomes: Take “Embolization” as the prior therapy Technical groups of endovascular Tx of PCBS
3 groups by pathological locations and endovascular methods:
1. Group 1 (Branch lesion): lesion located in the ECA and its branches — Treated with embolization
2. Group 2 (Trunk lesion): lesion located in the ICA to CCA
a. Group 2A: Treated with Embolization
b. Group 2B: Treated with stent-graft placement

22. Technique (1)
Group 1 (Branch lesion): lesion located in the ECA & its branches— Treated with embolization A B C
Acute PCBS. A grade 3 lesion (pseudoaneurysm) in the left lingular artery (A & B, arrow). It was embolized by injection of acrylic agent (C, arrow).
In group 1 patients, angiographic grade 1 & 2 lesions can be treated
with particle agents. Grade 3 & 4 lesions can be treated with coils or
acrylic agents.

23. Technique (2)
Group 2A: lesion located in the ICA to CCA & treated with embolization
Need a balloon occlusion test before treatment
Acute PCBS. An angiographic grade 3 lesion (A, arrow) in the ICA treated with fiber coils (B, arrows). A B
Difficult to perform a reliable
balloon occlusion test in:
Hypovolemic status with impaired consciousness
Very profuse bleeding cause the patient not able to tolerate heparinization

24. Technique (3)
Group 2B: lesion located in the ICA to CCA & reconstructive management with stent-graft placement D A B C
Indication of reconstructive management of PCBS:
1. Failed to pass or not able to
perform an occlusion test
2. Contralateral carotid
occlusion
3. Incomplete circle of Willis
Acute PCBS, angiographic grade 4 lesion (A, arrow). A Fluency stent-graft was placed in the left CCA (B, arrow). CTA 6 months later showed asymptomatic septic thrombosis of the stent-graft (C & D, arrows). Note the adjacent necrotic soft tissue (C & D, arrowheads).

25. Hemostatic period (mon)
Endovascular methods, Clinical severity and Postprocedural disease and the Outcomes of 96 patients of PCBS accepted endovascular Tx
Factors Outcomes
Technical
Hemostatic
Survival
Technical success
Complication
Rebleeding
Hemostatic period (mon)
Alive
Survival time
(mon)
Endovascular methods
Group 1 (Branch, n=40)
40 (100%)
1 (2.5%)
14 (35.0%)
10.9±18.8 (0.1-80)
9 (22.5%)
12.2±20.1 (0.2-80)
Group 2A (EM, n=38)
38 (100%)
9 (23.7%)
5 (13.2%)
7.6±14.6 ( )
11 (29.0%)
7.7±14.6 ( )
Group 2B (RE, n=18)
18 (100%)
9 (50.0%)
7 (38.9%)
2.9±3.0 ( )
2 (11.1%)
11.4±25.2 ( )
Total (n=96)
96 (100%)
19 (19.8%)
26 (27.1%)
8.1±34.7 ( )
22 (22.9%)
10.3±34.1 ( ) P*
1.0
0.0001
0.0435
0.2367
0.7440
0.1392
P**
0.0052
0.0247
0.1343
0.4716
0.0598
P***
0.0489
0.0284
0.9439
0.9292
0.1846
Clinical Severity
Ongoing (n=49)
49(100%)
4(8.2%)
8(16.3%)
11.0±19.7 ( )
11(22.5%)
11.5±19.6 ( )
Acute (n=47)
47(100%)
15(31.9%)
18(38.3%)
5.1±8.6 ( )
11(23.4%)
9.0±19.1 ( ) P
0.0035
0.0155
0.0216
0.4159
0.0709
Postprocedural clinical disease
Resolution/Regression (n=21)
21(100%)
2(9.5%)
3(14.3%)
26.0±25.7 ( )
14 (66.7%)
34.1±30.6 ( )
Persistence/progression (n=75)
75(100%)
17(22.7%)
23(30.7%)
3.1±3.8 ( )
8 (10.7%)
3.6±4.0 ( ) 1
0.2289
0.1714
<0.0001
P* = group 1 vs group 2A vs group 2B
P** = group 1 vs 2A
P*** = group 2A vs 2B
Chang FC, PLoS One

26. 1) Endovascular Methods & Outcomes
Embolization: group 1 (branch lesion) has higher rebleeding than group 2A (trunk lesion).
Reasons: a) Wide anatomical distribution of group 1 increased the chance of rebleeding
from the reconstituted collaterals; b) Embolization of ECA and its branches may increase
focal ischemic insult and impair the subsequent soft tissue healing.
Trunk lesions: group 2A (embolization) has lower technical complication and rebleeding than the group 2B (stent-graft).
Reasons: a) High technical complication of group 2B: inadequate premedication in
emergent status, risk of septic thrombosis of the stent-graft in a contaminated field,
delayed marginal stenosis by the strong radial force of stent-graft. b) High rebleeding of
group 2B: limited hemostatic effect if the disease process beyond the margin
of the deployed stent-graft

27. 2) Clinical Severity/Emergency & Outcomes
The patients of ongoing PCBS (non-emergent) are better than those of acute PCBS (emergent).
We suggest perform early endovascular management of PCBS when the patients were in non-emergent clinical status.
Benefits of early intervention of PCBS:
1. Worse clinical condition in acute PCBS than ongoing PCBS (ex. Massive bleeding with choking or aspiration)
2. Vascular collapse of the ECA in advanced disease with hypovolemic status— may temporarily miss the lesions during angiogram
3. Difficult to finish a complete balloon occlusion test in hypovolemic status with impaired consciousness.
4. Difficult to provide premedication for patients of acute CBS accepted emergent stent-graft placement.

28. D. Aggressive management of clinical disease processes
The hemostatic and survival outcomes are influenced by the control of postprocedural clinical diseases
Benefit of control of postprocedural clinical diseases (tumor or soft tissue lesion):
1. To restore the blood supply to the carotid wall.
2. To prevent the contaminated soft tissue lesion progress to systemic infection
or sepsis.

29. E. Aggressive management of Complications technical complications of the 96 patients of PCBS accepted endovascular management
Group
Cases Description
Group 1
(n=40)
1 (2.5%)
Acute infarction (major stroke): reflux of acrylic adhesive from the lingulofacial trunk to ECA and ICA
Group 2A
(n=38)
4 (10.5%)
3 (7.9%)
1 (2.6%)
Acute cerebral ischemia (3 major stroke and 1 minor stroke): including 1 case of reflux of acrylic adhesive from proximal ECA to ICA with major stroke and 1 case of intraprocedural massive blood vomiting with choking and hypoxic encephalopathy
Delayed cerebral ischemia (1 TIA, 1 minor stroke and 1 major stroke)
Delayed brain abscess formation
Delayed dislodgement of the detachable balloon through a skin fistula
Group 2B
(n=18)
2 (11.1%)
7 (38.9%)
Acute infarction: acute embolism and major stroke
Delayed stenosis/occlusion of stent-graft:
4 marginal stenosis/occlusion (2 asymptomatic marginal stenosis, 2
occlusion with delayed major stroke)
3 delayed septic thrombosis (2 asymptomatic, 1 associated with brain
abscesses)
ECA: external carotid artery; ICA: internal carotid artery
Chang FC, PLoS One

30. Complication and Prevention (1): Group 1 Acute stroke by reflux of acylic agent from ECA to ICA
10 min A B C
Acute PCBS. A grade 4 lesion in the left linguofacial trunk (A, arrow & arrowhead). Because of adjacent soft tissue wound, we tried to embolize the trunk of left ECA and lingulofacial trunk with a single injection of acrylic agent (B, arrow). The injected acrylic agent was too much and had delayed reflux from the ECA to the ICA 10 minutes later (C, arrow) and caused major stroke of the patient.
Lesions located in the proximal trunk of ECA should treat as the way of group 2 patient---- by either embolization after an occlusion test or stent-graft placement.
Chang FC, 2013 Clin Radiol

31. Complication and Prevention (2): Group 2A Delayed stroke even passed an occlusion testB A C
Acute PCBS. A grade 4 lesion in the right carotid bifurcation (A, arrow). After a balloon occlusion test (B), embolization of the right ICA to CCA was done (C). The patient complicated with a delayed stroke 3 weeks later because of pneumonia with temporary hypotension (D, E)
** Cerebral ischemic symptoms by permanent carotid occlusion: 5-15%.
** Even the patient could pass an occlusion test, we still favor to give post-procedural medical management after embolization of the carotid artery (such as adequate hydration, oxygenation, appropriate elevation of blood pressure and control of infectious process) to prevent delayed complications.
** Except for occlusion test, a tailored evaluation of permanent carotid occlusion
in patients of ongoing PCBS is needed.

32. Complication and Prevention (3): Group 2B Rebleeding from the reconstituted ECA
Acute PCBS. A grade 3 lesion (A, arrow) in the right distal CCA treated with 2 stent-grafts (B). Two months later, right subclavian angiogram showed a pseudoaneurysm in the right superior thyroid artery (C, arrow) by the reconstituted right ECA (C, arrowhead) via the RT thyrocervical trunk. As the orifice of ECA was covered by the stent-grafts, we performed direct percutaneous puncture (D, arrow) of the right superior thyroid artery to do embolization.
Embolization of the trunk of ECA before stent-graft placement can be
considered if the pathological lesion located close to the carotid bifurcation.
Chang FC, 2007 AJNR

33. Complication and Prevention (4): Group 2B Overlapped stents with Type III Endoleak
Acute PCBS. A grade 4 lesion in the right carotid bifurcation (A, arrow). We deployed a first stent-graft but was short and had type 1 endoleak. So we deployed a second stent-graft from right ICA to CCA to overlap the first stent (B). Rebleeding 4 months later. Angiogram showed a type 3 endoleak (C & D, arrow) at the junction of the 2 stent-grafts (D, arrowhead).
** To overlap a stent within a deployed stent-graft in the mobile neck region can erode the deployed stent-graft and cause type 3 endoleak.
** Suggest using a single stent-graft with appropriate length to cover the whole diseased carotid artery.
Chang FC, 2008 Clin Radiol

34. A B Fully opened Incompletely opened
Complication and Prevention (5): Group 2B Acute in-stent thrombosis in carotid stenosis
Yellow: metallic stent
Red: graft
Fully opened
Incompletely opened A B
Acute PCBS. A grade 4 lesion (A, arrow) in the right carotid bifurcation with long-segmental stenosis (A, arrowheads) of the ICA. A stent-graft was placed which complicated with acute in-stent thrombosis and occlusion of the ICA (B).
** Severe stenosis of carotid artery is a relative contraindication for stent-graft
placement because of “curtain effect” of the incompletely opened graft. A
minimal vascular diameter of 4mm is usually needed for carotid stent-graft
placement.
** Prevention: Bypass surgery + embolization; angioplasty of the stenotic
segment before stenting.
Chang FC, 2006 AJNR

35. Complication and Prevention (6): Group 2B Septic Thrombosis with Brain Abscess Formation
Ongoing PCBS. A grade 3 lesion in the left carotid bifurcation (A, arrow) treated with deployment of 2 fiber coils in the left ECA and stent-graft placement (B). Brain abscesses were noted 4 months later (C, arrowheads). The left carotid stent-graft was located in a contaminated mucosal defect (arrowheads) with septic thrombosis (arrow).
** Prevention: 1) Take embolization as the prior way of management
2) Give prophylactic antibiotics
3) A new stent system with better barrier to infective pathogens
or with anti-infective coating is favored.
Chang FC, 2006 AJNR

36. Complication and Prevention (7): Group 2B Distal Marginal Stenosis
Ongoing PCBS. A grade 1 lesion in the left mid-CCA (A,B) treated with a stent-graft placement. On CTA, the left carotid artery showed good patency in the first post-stenting month (C) but had significant distal marginal stenosis in a 4-month F/U (arrowheads, D). Dynamic change of post-irradiated necrosis and presence of a large soft tissue fistula was also found (D,E).
** Note: The marginal stenosis is caused by the straightened effect & strong radial force of the stent-graft. So close postprocedural F/U is indicated.
** Prevention: 1) Angioplasty of the stenosis of the stenotic segment; 2) A new stent system with acceptable radial force is needed.
Chang FC, 2008 J Vas Surg

37. Conclusion Strategy of endovascular management of PCBS:
1. A modified classification of PCBS: Acute & Ongoing
2. Perform pre-procedural and post-procedural CT/CTA to evaluate the disease process of PCBS
3. Taking embolization as the prior strategy
4. Performing early endovascular intervention
5. Aggressive management of the postprocedural clinical disease & complications

38. Thank You fcchang374@gmail.com
Reference of Endovascular Tx of PCBS of Taipei Veterans General Hospital
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Chang FC, et al. Carotid blowout syndrome in patients of head and neck cancers: reconstructive management by self-expandable stent-grafts. AJNR Am J Neuroradio 2007;28:
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Thank You