INTERVENTIONAL NEURORADIOLOGY
VOLUME 21 - No. 4 august 2015 ISSN 1591-0199 Online ISSN 2385-2011
Volume 21, No. 4, Pages 421 - 560, 2015
Journal of Peritherapeutic Neuroradiology, Surgical Procedures and Related Neurosciences Official Journal of: WFITN - World Federation of Interventional and Therapeutic Neuroradiology AAFITN - Asian & Australasian Federation of Interventional & Therapeutic Neuroradiology SAWITN - South American Working Group in Interventional and Therapeutic Neuroradiology The Chinese INR Coordinating Committee of the Chinese Doctor Association INSHCM - Interventional Neuroradiology Society of HCM City, Viet Nam Journal sponsored by JSNET - Japanese Society of Neuro Endovascular Therapy FIO - Italian Federation of Ozone Therapy Interventional Neuroradiology is published in cooperation with the American Journal of Neuroradiology
Case Report
Endovascular treatment of an infected pseudoaneurysm secondary to retropharyngeal abscess in a child
Interventional Neuroradiology 2015, Vol. 21(4) 538–542 ! The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1591019915590073 ine.sagepub.com
Waleed Brinjikji1, Felix E Diehn1, Christopher W Lindsay2 and Jonathan M Morris1
Abstract We describe a rare case of carotid pseudoaneurysm secondary to a retropharyngeal abscess, treated with coil embolization in a 2-year-old boy. The patient presented to an emergency department with symptoms suggesting meningitis but was subsequently diagnosed with streptococcal pharyngitis. He was discharged home on oral antibiotics after a short hospitalization. He returned to the emergency department two weeks later with limited neck motion and pain. Neck CT demonstrated a retropharyngeal abscess with a large left cervical internal carotid artery (ICA) pseudoaneurysm. The petrous ICA distal to the pseudoaneurysm had thrombosed prior to treatment. The ICA proximal to the pseudoaneurysm was sacrificed with coil embolization. Post-treatment imaging demonstrated complete thrombosis of the pseudoaneurysm but also demonstrated acute strokes in the left MCA/ACA watershed distribution. His parents noted that the patient was clumsier and exhibited some mild speech changes and a steppage gait prior to evaluation in the ED; therefore, these were thought to be secondary to emboli from partial thrombosis of the pseudoaneurysm prior to treatment. The patient was discharged home in good condition and his neurological function improved.
Keywords Endovascular, carotid blowout, stenting, coiling
Background Retropharyngeal abscesses in children require prompt diagnosis and treatment. Commonly associated complications include extension to the prevertebral space resulting in osteomyelitis-discitis, airway compromise, sepsis, and mediastinitis.1 In the pre-antibiotic era, retropharyngeal abscesses were known to be associated with bleeding complications secondary to pseudoaneurysm formation of the cervical internal carotid artery (ICA) or external carotid artery (ECA) branches.2 We describe a rare case of a 2-year-old boy who presented to the emergency department with a large retropharyngeal abscess and associated cervical ICA pseudoaneurysm that was subsequently treated with sacrifice of the proximal ICA with endovascular coil embolization.
empirically treated for bacterial meningitis. The streptococcal swab was positive for streptococcal pharyngitis and the lumbar puncture results were negative for infection. On admission, his C-reactive protein (CRP) was elevated to 189 and his white blood cell (WBC) count was 24,000. He was then discharged two days later on oral antibiotics for treatment of streptococcal pharyngitis. During the following week he clinically improved but then began to deteriorate, experiencing left neck pain, swelling and limited motion. He again presented to the emergency department and a neck computed tomography (CT) with intravenous (IV) contrast was performed. This demonstrated a large retropharyngeal abscess with an associated 3.9 cm cervical ICA pseudoaneurysm.
Case presentation A 2-year-old boy with a past medical history significant for a tonsillectomy eight months prior and no other comorbidities presented to an emergency department with vomiting, fever, and neck pain and stiffness. He underwent a lumbar puncture in the emergency department as well as a streptococcal throat swab and was
1
Department of Radiology, Mayo Clinic, USA Department of Radiology, Mayo Clinic Health System, USA
2
Corresponding author: Waleed Brinjikji, Mayo Clinic, Department of Radiology, 200 1st St. SW, Rochester, MN 55905, USA. Email: [email protected]
Brinjikji et al.
539
Figure 1. (a) Axial contrast-enhanced CTA image demonstrates a large, peripherally enhancing retropharyngeal abscess with associated cervical internal carotid artery (ICA) pseudoaneurysm. (b) Three-dimensional reconstruction of the CTA demonstrates the large medially projecting pseudoaneurysm with no contrast opacification distally. (c) Axial CTA image distal to the pseudoaneurysm demonstrates thrombus formation in the petrous segment of the left ICA (circle); the right petrous carotid is patent (curved arrow). CTA: computed tomography angiography.
Investigations The neck computed tomography angiography (CTA) with IV contrast performed on presentation to the emergency department demonstrated a 5.5 cm peripherally enhancing left retropharyngeal fluid collection consistent with abscess. Within the fluid collection was a 3.9 cm left distal cervical ICA pseudoaneurysm (Figure 1). The petrous ICA distal to the pseudoaneurysm was thrombosed; however, there was contrast opacification of the left ICA at and distal to the proximal petrous segment. The intracranial arterial circulation was normal in appearance. Non-contrast head CT demonstrated no evidence of acute infarction or hemorrhage. A cerebral angiogram was performed to further evaluate the pseudoaneurysm and intracranial circulation for the purposes of treatment planning (Figure 2). Injection of the left ICA demonstrated the large pseudoaneurysm. There was no antegrade flow in the ICA distal to the pseudoaneurysm consistent with thrombosis. The angiogram demonstrated excellent collateral circulation to the left ICA territory through both the contralateral ICA and vertebrobasilar circulation. Interestingly, upon injection of the left ECA there was retrograde filling of the petrous and cavernous ICA through the ECA-ICA anastomosis between the artery of the foramen rotundum and the inferolateral trunk (Figure 2).
Treatment Following the diagnostic angiogram the decision was made to sacrifice the left ICA proximal to the pseudoaneurysm with coil embolization. The ICA distal to the aneurysm was already occluded owing to thrombus formation prior to treatment as demonstrated in Figure 1. Several detachable coils were deployed into the ICA
proximal to the pseudoaneurysm but not within the pseudoaneurysm lumen. The final control angiogram of the left common carotid artery (CCA) demonstrated occlusion of the ICA and no filling of the pseudoaneurysm (Figure 3).
Outcome and follow-up Following treatment the patient was kept on IV antibiotics for the retropharyngeal abscess. A follow-up CTA was performed three days post-coiling that demonstrated no filling of the pseudoaneurysm and shrinking of the retropharyngeal abscess (Figure 4). Magnetic resonance imaging (MRI) of the head and neck was performed that demonstrated watershed infarcts in the left anterior cerebral artery (ACA)/middle cerebral artery (MCA) territories. The patient’s parents had noticed some changes in speech and a steppage gate on the left prior to the patient’s presentation to the emergency department. This, in combination with the presence of the pre-coiling thrombus in the petrous ICA, led the neurology service to conclude that these were present prior to treatment. Approximately 2cc of sterile-appearing fluid from the abscess were aspirated under ultrasound guidance and no bacteria grew, likely owing to the patient’s prior antibiotic therapy. The patient did not undergo surgical or percutaneous draining of the abscess and no surgery was performed for pseudoaneurysm resection. The patient was discharged to home on IV antibiotics and his neurological deficits were nearly completely resolved.
Discussion Infectious pseudoaneurysms of the ICA are an exceedingly rare complication of retropharyngeal abscess in the modern era of antibiotics.3 While these lesions were rare even in the pre-antibiotic era, there are
540
Interventional Neuroradiology 21(4)
Figure 2. (a) Right ICA angiogram demonstrates filling of the contralateral ACA and MCA through the Acomm. Lack of contrast opacification in the Pcomm segment of the left ICA (black arrow) is due to contrast washout from a large left Pcomm. There is slow filling of the cavernous left ICA (white arrow). (b) Right vertebral artery injection demonstrates contrast opacification of the left ICA and MCA through a large Pcomm as well as retrograde filling of the left supraclinoid ICA (white arrow). (c) Left CCA injection demonstrates filling of the left ICA pseudoaneurysm. There is contrast opacification of the ICA distal to the pseudoaneurysm through an inferolateral trunk-artery of the foramen rotundum anastomosis (white arrows). (d) Left ICA injection demonstrates contrast opacification of large pseudoaneurysm. ACA: anterior cerebral artery; MCA: middle cerebral artery; Acomm: anterior communicating artery; Pcomm: posterior communicating artery; ICA: internal carotid artery; CCA: common carotid artery.
several reports and series from the early 20th century documenting cases of retropharyngeal and peritonsillar abscesses resulting in hemorrhage and death due to pseudoaneurysm formation of the ICA and ECA. The largest series reported by Salinger and Pearlman in 1933 reported more than 200 such cases, more than half of which were fatal.2 These lesions often present as a pulsatile lateral neck mass with fever, tenderness and dysphagia due to the aneurysm. Histologically, these are characterized by erosion of the arterial wall with changes of acute arteritis and cellulitis of surrounding tissue.4 When left untreated, these can result in fatal hemorrhage as well as ischemia secondary to shower emboli, as in this case.
Because of the rarity of these lesions in the modern era, there is little known regarding the best treatment options. Current treatment choices include surgical ligation with or without resection of the pseudoaneurysm and endovascular therapies. Surgical ligation is traditionally preferred over endovascular treatment as it allows for definitive treatment of the pseudoaneurysm as well as debridement of any infected tissue. Complications related to surgical ligation include cranial nerve deficits and Horner’s syndrome.5 Some have advocated combined endovascular and surgical management of these lesions to mitigate perioperative hemorrhagic complications with either pre-operative embolization of the pseudoaneurysm proximally and/
Brinjikji et al.
541
Figure 3. (a) Non-subtracted angiographic image following left CCA injection demonstrates coil occlusion of the left ICA proximal to the pseudoaneurysm. (b) Subtracted images demonstrate no filling of the pseudoaneurysm. CCA: common carotid artery; ICA: internal carotid artery.
Figure 4. Three days post-treatment: (a) Axial non-contrast CT image demonstrates pre-contrast hyperintensity within the pseudoaneurysm (circle) likely representing thrombus. (b) Post-contrast CTA image demonstrates no contrast opacification of the pseudoaneurysm (circle). The contralateral ICA is well opacified. (c), (d) Axial DWI images demonstrate areas of restricted diffusion on the left in a watershed distribution. CT: computed tomography; CTA: computed tomography angiography; ICA: internal carotid artery; DWI: diffusionweighted imaging.
542 or distally or even post-surgical occlusion of the ICA distal to the pseudoaneurysm following proximal ICA ligation.6 Endovascular therapies that have been reported in the literature include covered stent placement, endosaccular coiling or balloon exclusion and parent artery sacrifice with either balloons or coils.7 Over the past 15 years, multiple case reports on treatment of these lesions have highlighted the role of endovascular therapy. By far, the most commonly reported technique is carotid sacrifice through coiling the ICA distal and proximal to the pseudoaneurysm.8 Endovascular treatment with detachable balloons has also been reported to be effective.9 In our case, coiling distal to the lesion was not considered as 1) the ICA distal to the pseudoaneurysm was already thrombosed and 2) accessing the distal ICA could potentially increase the risk of perioperative stroke as it would require coursing the microcatheter through the vertebrobasilar system to the left posterior communicating artery to access the left ICA or using the contralateral ICA and crossing the anterior communicating artery to access the left ICA. Parent artery preservation with covered stent-graft deployment has also been shown to be effective in treatment of these lesions. One major advantage of covered stent placement is the ability to maintain patency of the ICA. One case report describing successful deployment of a covered stent for treatment of an infected pseudoaneurysm demonstrated patency of the stent at 18month follow-up.10 Others have reported the use of concomitant saccular coiling with stent-graft placement as a means to reduce mass effect from the aneurysm on the ICA.11 Overall, covered stent placement appears to be a viable option for treatment of these pseudoaneurysms, especially in patients with poor intracranial collateral circulation. In our case stent-graft placement was not considered owing to the excellent collateral circulation to the left ICA territory and the presence of thrombus in the ICA distal to the pseudoaneurysm. In addition to the potential for embolic complications inherent in any neuroendovascular procedure, one potential drawback to endovascular-only approaches is the risk of infection seeding the embolic material or stent-graft. However, to date, there are no reported cases of infection of coil or stent material during treatment of infectious pseudoaneurysms of the cervical ICA. This may be due to the fact that these patients are often treated with long-term antibiotics for treatment of the peritonsillar or retropharyngeal infection.
Key messages . Infectious pseudoaneurysm formation of the internal carotid artery (ICA) is a rare but potentially devastating complication of retropharyngeal abscess.
Interventional Neuroradiology 21(4) . Prompt diagnosis and treatment of these lesions is essential to reducing the risks of stroke and hemorrhage. . Endovascular techniques including parent artery sacrifice and covered stent placement can be effective in treating these lesions. No case of infection of these foreign bodies has been reported. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest None declared.
References 1. Stoner MJ and Dulaurier M. Pediatric ENT emergencies. Emerg Med Clin North Am 2013; 31: 795–808. 2. Salinger S and Pearlman S. Hemorrhage from pharyngeal and peritonsillar abscesses: Report of cases, resume of the literature and discussion of ligation of the carotid artery. Arch Otolaryngol 1933; 18: 464–509. 3. Ferna´ndez CA, Tagarro S, Lozano-Arnilla CG, et al. Internal carotid pseudoaneurysm within a parapharyngeal infection: An infrequent complication of difficult diagnosis. Otolaryngol Head Neck Surg 2005; 132: 671–673. 4. Hogarth TB. Intra-pharyngeal haemorrhage from the internal carotid artery. Report of a case and arteriographic findings. J Laryngol Otol 1959; 73: 764–767. 5. Willemsen P, De Roover D, Kockx M, et al. Mycotic common carotid artery aneurysm in an immunosuppressed pediatric patient: Case report. J Vasc Surg 1997; 25: 784–785. 6. Gonda RL Jr, Gutierrez OH, Hengerer AS, et al. Pharyngeal abscess with external carotid artery erosion and pseudoaneurysm. A combined radiologic and surgical management. Pediatr Neurosurg 1990; 16: 21–24. 7. Tsai TC, Barot N, Dalman R, et al. Combined endovascular and open operative approach for mycotic carotid aneurysm. J Vasc Surg 2010; 51: 1514–1516. 8. DeFatta RJ, Verret DJ and Bauer P. Extracranial internal carotid artery pseudoaneurysm. Int J Pediatr Otorhinolaryngol 2005; 69: 1135–1139. 9. da Silva PS and Waisberg DR. Internal carotid artery pseudoaneurysm with life-threatening epistaxis as a complication of deep neck space infection. Pediatr Emerg Care 2011; 27: 422–424. 10. Requejo F, Sierre S, Lipsich J, et al. Endovascular treatment of post-pharyngitis internal carotid artery pseudoaneurysm with a covered stent in a child: A case report. Childs Nerv Syst 2013; 29: 1369–1373. 11. Makeieff M, Pelliccia P, Mondain M, et al. Pseudoaneurysm of the internal carotid artery complicating deep neck space infection. J Pediatr 2010; 157: 510.
VOLUME 21 - No. 4 august 2015 ISSN 1591-0199 Online ISSN 2385-2011
Volume 21, No. 4, Pages 421 - 560, 2015
Journal of Peritherapeutic Neuroradiology, Surgical Procedures and Related Neurosciences Official Journal of: WFITN - World Federation of Interventional and Therapeutic Neuroradiology AAFITN - Asian & Australasian Federation of Interventional & Therapeutic Neuroradiology SAWITN - South American Working Group in Interventional and Therapeutic Neuroradiology The Chinese INR Coordinating Committee of the Chinese Doctor Association INSHCM - Interventional Neuroradiology Society of HCM City, Viet Nam Journal sponsored by JSNET - Japanese Society of Neuro Endovascular Therapy FIO - Italian Federation of Ozone Therapy Interventional Neuroradiology is published in cooperation with the American Journal of Neuroradiology
Case Report
Endovascular treatment of an infected pseudoaneurysm secondary to retropharyngeal abscess in a child
Interventional Neuroradiology 2015, Vol. 21(4) 538–542 ! The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1591019915590073 ine.sagepub.com
Waleed Brinjikji1, Felix E Diehn1, Christopher W Lindsay2 and Jonathan M Morris1
Abstract We describe a rare case of carotid pseudoaneurysm secondary to a retropharyngeal abscess, treated with coil embolization in a 2-year-old boy. The patient presented to an emergency department with symptoms suggesting meningitis but was subsequently diagnosed with streptococcal pharyngitis. He was discharged home on oral antibiotics after a short hospitalization. He returned to the emergency department two weeks later with limited neck motion and pain. Neck CT demonstrated a retropharyngeal abscess with a large left cervical internal carotid artery (ICA) pseudoaneurysm. The petrous ICA distal to the pseudoaneurysm had thrombosed prior to treatment. The ICA proximal to the pseudoaneurysm was sacrificed with coil embolization. Post-treatment imaging demonstrated complete thrombosis of the pseudoaneurysm but also demonstrated acute strokes in the left MCA/ACA watershed distribution. His parents noted that the patient was clumsier and exhibited some mild speech changes and a steppage gait prior to evaluation in the ED; therefore, these were thought to be secondary to emboli from partial thrombosis of the pseudoaneurysm prior to treatment. The patient was discharged home in good condition and his neurological function improved.
Keywords Endovascular, carotid blowout, stenting, coiling
Background Retropharyngeal abscesses in children require prompt diagnosis and treatment. Commonly associated complications include extension to the prevertebral space resulting in osteomyelitis-discitis, airway compromise, sepsis, and mediastinitis.1 In the pre-antibiotic era, retropharyngeal abscesses were known to be associated with bleeding complications secondary to pseudoaneurysm formation of the cervical internal carotid artery (ICA) or external carotid artery (ECA) branches.2 We describe a rare case of a 2-year-old boy who presented to the emergency department with a large retropharyngeal abscess and associated cervical ICA pseudoaneurysm that was subsequently treated with sacrifice of the proximal ICA with endovascular coil embolization.
empirically treated for bacterial meningitis. The streptococcal swab was positive for streptococcal pharyngitis and the lumbar puncture results were negative for infection. On admission, his C-reactive protein (CRP) was elevated to 189 and his white blood cell (WBC) count was 24,000. He was then discharged two days later on oral antibiotics for treatment of streptococcal pharyngitis. During the following week he clinically improved but then began to deteriorate, experiencing left neck pain, swelling and limited motion. He again presented to the emergency department and a neck computed tomography (CT) with intravenous (IV) contrast was performed. This demonstrated a large retropharyngeal abscess with an associated 3.9 cm cervical ICA pseudoaneurysm.
Case presentation A 2-year-old boy with a past medical history significant for a tonsillectomy eight months prior and no other comorbidities presented to an emergency department with vomiting, fever, and neck pain and stiffness. He underwent a lumbar puncture in the emergency department as well as a streptococcal throat swab and was
1
Department of Radiology, Mayo Clinic, USA Department of Radiology, Mayo Clinic Health System, USA
2
Corresponding author: Waleed Brinjikji, Mayo Clinic, Department of Radiology, 200 1st St. SW, Rochester, MN 55905, USA. Email: [email protected]
Brinjikji et al.
539
Figure 1. (a) Axial contrast-enhanced CTA image demonstrates a large, peripherally enhancing retropharyngeal abscess with associated cervical internal carotid artery (ICA) pseudoaneurysm. (b) Three-dimensional reconstruction of the CTA demonstrates the large medially projecting pseudoaneurysm with no contrast opacification distally. (c) Axial CTA image distal to the pseudoaneurysm demonstrates thrombus formation in the petrous segment of the left ICA (circle); the right petrous carotid is patent (curved arrow). CTA: computed tomography angiography.
Investigations The neck computed tomography angiography (CTA) with IV contrast performed on presentation to the emergency department demonstrated a 5.5 cm peripherally enhancing left retropharyngeal fluid collection consistent with abscess. Within the fluid collection was a 3.9 cm left distal cervical ICA pseudoaneurysm (Figure 1). The petrous ICA distal to the pseudoaneurysm was thrombosed; however, there was contrast opacification of the left ICA at and distal to the proximal petrous segment. The intracranial arterial circulation was normal in appearance. Non-contrast head CT demonstrated no evidence of acute infarction or hemorrhage. A cerebral angiogram was performed to further evaluate the pseudoaneurysm and intracranial circulation for the purposes of treatment planning (Figure 2). Injection of the left ICA demonstrated the large pseudoaneurysm. There was no antegrade flow in the ICA distal to the pseudoaneurysm consistent with thrombosis. The angiogram demonstrated excellent collateral circulation to the left ICA territory through both the contralateral ICA and vertebrobasilar circulation. Interestingly, upon injection of the left ECA there was retrograde filling of the petrous and cavernous ICA through the ECA-ICA anastomosis between the artery of the foramen rotundum and the inferolateral trunk (Figure 2).
Treatment Following the diagnostic angiogram the decision was made to sacrifice the left ICA proximal to the pseudoaneurysm with coil embolization. The ICA distal to the aneurysm was already occluded owing to thrombus formation prior to treatment as demonstrated in Figure 1. Several detachable coils were deployed into the ICA
proximal to the pseudoaneurysm but not within the pseudoaneurysm lumen. The final control angiogram of the left common carotid artery (CCA) demonstrated occlusion of the ICA and no filling of the pseudoaneurysm (Figure 3).
Outcome and follow-up Following treatment the patient was kept on IV antibiotics for the retropharyngeal abscess. A follow-up CTA was performed three days post-coiling that demonstrated no filling of the pseudoaneurysm and shrinking of the retropharyngeal abscess (Figure 4). Magnetic resonance imaging (MRI) of the head and neck was performed that demonstrated watershed infarcts in the left anterior cerebral artery (ACA)/middle cerebral artery (MCA) territories. The patient’s parents had noticed some changes in speech and a steppage gate on the left prior to the patient’s presentation to the emergency department. This, in combination with the presence of the pre-coiling thrombus in the petrous ICA, led the neurology service to conclude that these were present prior to treatment. Approximately 2cc of sterile-appearing fluid from the abscess were aspirated under ultrasound guidance and no bacteria grew, likely owing to the patient’s prior antibiotic therapy. The patient did not undergo surgical or percutaneous draining of the abscess and no surgery was performed for pseudoaneurysm resection. The patient was discharged to home on IV antibiotics and his neurological deficits were nearly completely resolved.
Discussion Infectious pseudoaneurysms of the ICA are an exceedingly rare complication of retropharyngeal abscess in the modern era of antibiotics.3 While these lesions were rare even in the pre-antibiotic era, there are
540
Interventional Neuroradiology 21(4)
Figure 2. (a) Right ICA angiogram demonstrates filling of the contralateral ACA and MCA through the Acomm. Lack of contrast opacification in the Pcomm segment of the left ICA (black arrow) is due to contrast washout from a large left Pcomm. There is slow filling of the cavernous left ICA (white arrow). (b) Right vertebral artery injection demonstrates contrast opacification of the left ICA and MCA through a large Pcomm as well as retrograde filling of the left supraclinoid ICA (white arrow). (c) Left CCA injection demonstrates filling of the left ICA pseudoaneurysm. There is contrast opacification of the ICA distal to the pseudoaneurysm through an inferolateral trunk-artery of the foramen rotundum anastomosis (white arrows). (d) Left ICA injection demonstrates contrast opacification of large pseudoaneurysm. ACA: anterior cerebral artery; MCA: middle cerebral artery; Acomm: anterior communicating artery; Pcomm: posterior communicating artery; ICA: internal carotid artery; CCA: common carotid artery.
several reports and series from the early 20th century documenting cases of retropharyngeal and peritonsillar abscesses resulting in hemorrhage and death due to pseudoaneurysm formation of the ICA and ECA. The largest series reported by Salinger and Pearlman in 1933 reported more than 200 such cases, more than half of which were fatal.2 These lesions often present as a pulsatile lateral neck mass with fever, tenderness and dysphagia due to the aneurysm. Histologically, these are characterized by erosion of the arterial wall with changes of acute arteritis and cellulitis of surrounding tissue.4 When left untreated, these can result in fatal hemorrhage as well as ischemia secondary to shower emboli, as in this case.
Because of the rarity of these lesions in the modern era, there is little known regarding the best treatment options. Current treatment choices include surgical ligation with or without resection of the pseudoaneurysm and endovascular therapies. Surgical ligation is traditionally preferred over endovascular treatment as it allows for definitive treatment of the pseudoaneurysm as well as debridement of any infected tissue. Complications related to surgical ligation include cranial nerve deficits and Horner’s syndrome.5 Some have advocated combined endovascular and surgical management of these lesions to mitigate perioperative hemorrhagic complications with either pre-operative embolization of the pseudoaneurysm proximally and/
Brinjikji et al.
541
Figure 3. (a) Non-subtracted angiographic image following left CCA injection demonstrates coil occlusion of the left ICA proximal to the pseudoaneurysm. (b) Subtracted images demonstrate no filling of the pseudoaneurysm. CCA: common carotid artery; ICA: internal carotid artery.
Figure 4. Three days post-treatment: (a) Axial non-contrast CT image demonstrates pre-contrast hyperintensity within the pseudoaneurysm (circle) likely representing thrombus. (b) Post-contrast CTA image demonstrates no contrast opacification of the pseudoaneurysm (circle). The contralateral ICA is well opacified. (c), (d) Axial DWI images demonstrate areas of restricted diffusion on the left in a watershed distribution. CT: computed tomography; CTA: computed tomography angiography; ICA: internal carotid artery; DWI: diffusionweighted imaging.
542 or distally or even post-surgical occlusion of the ICA distal to the pseudoaneurysm following proximal ICA ligation.6 Endovascular therapies that have been reported in the literature include covered stent placement, endosaccular coiling or balloon exclusion and parent artery sacrifice with either balloons or coils.7 Over the past 15 years, multiple case reports on treatment of these lesions have highlighted the role of endovascular therapy. By far, the most commonly reported technique is carotid sacrifice through coiling the ICA distal and proximal to the pseudoaneurysm.8 Endovascular treatment with detachable balloons has also been reported to be effective.9 In our case, coiling distal to the lesion was not considered as 1) the ICA distal to the pseudoaneurysm was already thrombosed and 2) accessing the distal ICA could potentially increase the risk of perioperative stroke as it would require coursing the microcatheter through the vertebrobasilar system to the left posterior communicating artery to access the left ICA or using the contralateral ICA and crossing the anterior communicating artery to access the left ICA. Parent artery preservation with covered stent-graft deployment has also been shown to be effective in treatment of these lesions. One major advantage of covered stent placement is the ability to maintain patency of the ICA. One case report describing successful deployment of a covered stent for treatment of an infected pseudoaneurysm demonstrated patency of the stent at 18month follow-up.10 Others have reported the use of concomitant saccular coiling with stent-graft placement as a means to reduce mass effect from the aneurysm on the ICA.11 Overall, covered stent placement appears to be a viable option for treatment of these pseudoaneurysms, especially in patients with poor intracranial collateral circulation. In our case stent-graft placement was not considered owing to the excellent collateral circulation to the left ICA territory and the presence of thrombus in the ICA distal to the pseudoaneurysm. In addition to the potential for embolic complications inherent in any neuroendovascular procedure, one potential drawback to endovascular-only approaches is the risk of infection seeding the embolic material or stent-graft. However, to date, there are no reported cases of infection of coil or stent material during treatment of infectious pseudoaneurysms of the cervical ICA. This may be due to the fact that these patients are often treated with long-term antibiotics for treatment of the peritonsillar or retropharyngeal infection.
Key messages . Infectious pseudoaneurysm formation of the internal carotid artery (ICA) is a rare but potentially devastating complication of retropharyngeal abscess.
Interventional Neuroradiology 21(4) . Prompt diagnosis and treatment of these lesions is essential to reducing the risks of stroke and hemorrhage. . Endovascular techniques including parent artery sacrifice and covered stent placement can be effective in treating these lesions. No case of infection of these foreign bodies has been reported. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
Conflict of interest None declared.
References 1. Stoner MJ and Dulaurier M. Pediatric ENT emergencies. Emerg Med Clin North Am 2013; 31: 795–808. 2. Salinger S and Pearlman S. Hemorrhage from pharyngeal and peritonsillar abscesses: Report of cases, resume of the literature and discussion of ligation of the carotid artery. Arch Otolaryngol 1933; 18: 464–509. 3. Ferna´ndez CA, Tagarro S, Lozano-Arnilla CG, et al. Internal carotid pseudoaneurysm within a parapharyngeal infection: An infrequent complication of difficult diagnosis. Otolaryngol Head Neck Surg 2005; 132: 671–673. 4. Hogarth TB. Intra-pharyngeal haemorrhage from the internal carotid artery. Report of a case and arteriographic findings. J Laryngol Otol 1959; 73: 764–767. 5. Willemsen P, De Roover D, Kockx M, et al. Mycotic common carotid artery aneurysm in an immunosuppressed pediatric patient: Case report. J Vasc Surg 1997; 25: 784–785. 6. Gonda RL Jr, Gutierrez OH, Hengerer AS, et al. Pharyngeal abscess with external carotid artery erosion and pseudoaneurysm. A combined radiologic and surgical management. Pediatr Neurosurg 1990; 16: 21–24. 7. Tsai TC, Barot N, Dalman R, et al. Combined endovascular and open operative approach for mycotic carotid aneurysm. J Vasc Surg 2010; 51: 1514–1516. 8. DeFatta RJ, Verret DJ and Bauer P. Extracranial internal carotid artery pseudoaneurysm. Int J Pediatr Otorhinolaryngol 2005; 69: 1135–1139. 9. da Silva PS and Waisberg DR. Internal carotid artery pseudoaneurysm with life-threatening epistaxis as a complication of deep neck space infection. Pediatr Emerg Care 2011; 27: 422–424. 10. Requejo F, Sierre S, Lipsich J, et al. Endovascular treatment of post-pharyngitis internal carotid artery pseudoaneurysm with a covered stent in a child: A case report. Childs Nerv Syst 2013; 29: 1369–1373. 11. Makeieff M, Pelliccia P, Mondain M, et al. Pseudoaneurysm of the internal carotid artery complicating deep neck space infection. J Pediatr 2010; 157: 510.
