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Ruptured Aneurysms of the Occipital Artery Associated with Congenital Occipital Bone Defect
Case Report
Ruptured Aneurysms of the Occipital Artery Associated with Congenital Occipital Bone Defect Toshinari Kawasaki, Kazumichi Yoshida, Takayuki Kikuchi, Akira Ishii, Yasushi Takagi, Susumu Miyamoto
Key words Bone defect - Meningoencephalocele - Occipital artery - Traumatic aneurysm -
- BACKGROUND:
Traumatic aneurysms of the superficial temporal artery have been frequently reported in the literature, whereas traumatic aneurysms of the occipital artery (OA) are extremely rare.
- CASE
Abbreviations and Acronyms CT: Computed tomography ECA: External carotid artery NBCA: N-butyl-2-cyanoacrylate OA: Occipital artery STA: Superficial temporal artery Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan To whom correspondence should be addressed: Kazumichi Yoshida, M.D., Ph.D. [E-mail: [email protected]] Citation: World Neurosurg. (2016). http://dx.doi.org/10.1016/j.wneu.2016.09.116 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2016 Elsevier Inc. All rights reserved.
INTRODUCTION Aneurysms of the external carotid artery (ECA) can be caused by several mechanisms such as traumatic injury,1-4 infection,5 or iatrogenesis.6 Traumatic aneurysms of the superficial temporal artery (STA) have been frequently reported in the literature, whereas traumatic aneurysms of the occipital artery (OA) are extremely rare. We report the first case of traumatic ruptured aneurysms of the OA associated with meningoencephalocele caused by a congenital occipital bone defect.
CASE DESCRIPTION A 30-year-old man was emergently admitted to our hospital with the chief complaint of sudden neck swelling and pain during a football game. Initial computed tomography (CT) showed a large meningoencephalocele protruding from his occipital bone defect and a hematoma in his right neck, which rapidly increased in volume on follow-up CTs. His
DESCRIPTION: A 30-year-old man had been followed at another hospital for meningoencephalocele associated with his congenital occipital bone defect. He was admitted to our hospital with a chief complaint of neck swelling and pain during a football game. Computed tomography and magnetic resonance imaging showed a hematoma in his right neck along with the meningoencephalocele. In addition, it showed an atrophic cerebellum with a cyst protruding from his occipital bone defect. Digital subtraction angiography of the right OA showed 3 aneurysms responsible for the large hematoma in his neck. Endovascular embolization with 20% N-butyl-2-cyanoacrylate was performed for treatment of the ruptured aneurysms followed by emergent surgical evacuation of the hematoma. An occipital cranioplasty with titanium mesh was performed 10 months after the emergent intervention.
- CONCLUSIONS:
In this patient, the congenital occipital bone defect with meningoencephalocele might have been the remote source of risk for traumatic pseudoaneurysms along the muscle branches of the OA.
meningoencephalocele was initially diagnosed at another hospital when he was 3 years old, and a conservative approach with follow-up CTs had been taken until he reached adulthood. On admission to our hospital, his right neck was soft, reddened, and swollen but without a pulsatile nodule. Epidermolysis associated with purpura was confirmed on the surface of the neck. Blood examination showed slight evidence of an inflammatory reaction (white blood cell count, 12,400/mL; C-reactive protein level, 4.9 mg/dL) and anemia (hemoglobin level, 10.1 g/dL), although his immune reaction and coagulation tests were normal. Threedimensional CT of the bone (Figure 1) and magnetic resonance imaging (Figure 2) showed the large occipital bone defect and the hematoma in his right neck and meningoencephalocele, respectively. Digital subtraction angiography was performed to probe for causes of the hematoma in detail. Digital subtraction angiography showed 3 aneurysms in the branches of the right OA (Figure 3A).
WORLD NEUROSURGERY -: ---, MONTH 2016
Endovascular embolization with 20% N-butyl-2-cyanoacrylate (NBCA) was performed for obliteration of the aneurysms, which successfully restricted continued hemorrhage (Figure 3B). Because his neck swelling and the tension of his skin were still severe at the end of the endovascular intervention, surgical evacuation of the neck hematoma was subsequently performed under general anesthesia. The patient’s postoperative course was uneventful, and he was discharged from our hospital 30 days after admission. An occipital titanium mesh cranioplasty was performed 10 months after the emergent intervention both for cosmetic reasons and to prevent against future traumatic aneurysm formation. DISCUSSION Most traumatic aneurysms at the branches of the ECA are associated with contact sports and blunt trauma.1-4 Traumatic pseudoaneurysm formation usually takes
www.WORLDNEUROSURGERY.org
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CASE REPORT TOSHINARI KAWASAKI ET AL.
RUPTURED ANEURYSMS OF THE OA
Figure 3. (A) Three pseudoaneurysms (arrows) are confirmed by selective digital subtraction angiography of the right occipital artery. (B) All of the pseudoaneurysms have been completely obliterated by endovascular embolization using 20% N-butyl-2-cyanoacrylate.
Figure 1. An extensive occipital bone defect is clearly shown on three-dimensional computed tomography with bone windows.
2e6 weeks after external injury.7 Infectious5 and iatrogenic6 causes of ECA aneurysms have been infrequently reported in the literature. According to reports evaluating the pathologic findings of ECA aneurysms, pseudoaneurysm is more frequent than true aneurysm.8,9 Based on the analysis of 386 traumatic ECA aneurysms, Conner et al.7 reported
327 aneurysms of the STA, 27 of the internal maxillary artery, 26 of the facial artery, 2 of the OA, 2 of the lingual artery, 2 of the superior thyroid artery, and 1 of the supraorbital artery. The STA, internal maxillary artery, and facial artery are all susceptible to blunt trauma because these arteries are not protected by bone and soft tissue, which might explain the high incidence of traumatic ECA aneurysms of these arteries. To the best of our knowledge, this is the first case of multiple traumatic ruptured aneurysms of the OA in the setting of a
Figure 2. Axial (left) and coronal (right) T1-weighted magnetic resonance images show an atrophic cerebellum with a large cyst protruding through the bone defect. Extensive hematoma in the patient’s right neck is also confirmed by the coronal image (right).
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meningoencephalocele associated with a congenital occipital bone defect. During development, the occipital bone defect might have caused atrophy and vulnerability of the cervical supportive muscles attached to the occipital bone. The skin covering the meningoencephalocele was noted to be extended and thinned. Under those circumstances, the protective ability of the skin might have been reduced because of secondary structural changes such as hemorrhage, ulceration, and epithelization. Thus, mild blunt trauma to his neck could more easily result in the formation of multiple aneurysms. Conservative treatment of the meningoencephalocele and occipital bone defect without cranioplasty might have indirectly influenced the formation of multiple aneurysms in this patient. The reported options for treatment of ECA aneurysm are surgical resection,2,4-6,10 endovascular coil embolization,3,11 embolization with thrombin,12,13 and external compression with an echo duplex probe.1,14 Although embolization with thrombin using ultrasonography is convenient and minimally invasive, it has some disadvantages such as recanalization, allergic reaction, and ischemic complications. Vogelaere et al.6 reported that surgical resection was performed for a traumatic STA aneurysm after unsuccessful external compression with a duplex probe. In our patient, multiple aneurysms of the OA were obliterated by endovascular embolization with NBCA and the large
WORLD NEUROSURGERY, http://dx.doi.org/10.1016/j.wneu.2016.09.116
CASE REPORT TOSHINARI KAWASAKI ET AL.
RUPTURED ANEURYSMS OF THE OA
hematoma in the neck was surgically evacuated, which led to a favorable result.
4. Lalak NJ, Farmer E. Traumatic pseudoaneurysm of the superficial temporal artery associated with facial nerve palsy. J Cardiovasc Surg (Torino). 1996;37:119-123.
CONCLUSIONS
5. Forbes TL, Tong M. External carotid artery pseudoaneurysm in an immunocompromised patient. Can J Surg. 2008;51:E11-E12.
We describe the first case of traumatic multiple ruptured aneurysms of the OA associated with meningoencephalocele caused by a congenital occipital bone defect that might have been a remote cause of aneurysm formation. Emergent endovascular embolization with NBCA for the aneurysms, followed by surgical evacuation of the hematoma and elective occipital cranioplasty, were performed. REFERENCES 1. De Vogelaere K. Traumatic aneurysm of the superficial temporal artery: case report. J Trauma. 2004;57:399-401. 2. Fox JT, Cordts PR, Gwinn BC 2nd. Traumatic aneurysm of the superficial temporal artery: case report. J Trauma. 1994;36:562-564. 3. Hong JT, Lee SW, Ihn YK, Son BC, Sung JH, Kim IS, et al. Traumatic pseudoaneurysm of the superficial temporal artery treated by endovascular coil embolization. Surg Neurol. 2006;66:86-88.
6. Angevine PD, Connolly ES Jr. Pseudoaneurysms of the superficial temporal artery secondary to placement of external ventricular drainage catheters. Surg Neurol. 2002;58:258-260. 7. Conner WC 3rd, Rohrich RJ, Pollock RA. Traumatic aneurysms of the face and temple: a patient report and literature review, 1644 to 1998. Ann Plast Surg. 1998;41:321-326. 8. Kim HS, Son BC, Lee SW, Kim IS. A rare case of spontaneous true aneurysm of the occipital artery. J Korean Neurosurg Soc. 2010;47:310-312. 9. Rao VY, Hwang SW, Adesina AM, Jea A. Thrombosed traumatic aneurysm of the occipital artery: a case report and review of the literature. J Med Case Rep. 2012;6:203. 10. Campbell AS, Butler AP, Grandas OH. A case of external carotid artery pseudoaneurysm from hyoid bone fracture. Am Surg. 2003;69:534-535. 11. Mendez JC, Sendra J, Poveda P, Garcia-Leal R. Endovascular treatment of traumatic aneurysm of
WORLD NEUROSURGERY -: ---, MONTH 2016
the occipital artery. Cardiovasc Intervent Radiol. 2006; 29:486-487. 12. Bobinski L, Bostrom S, Hillman J, Theodorsson A. Postoperative pseudoaneurysm of the superficial temporal artery (S.T.A.) treated with Thrombostat (thrombin glue) injection. Acta Neurochir (Wien). 2004;146:1039-1041 [discussion: 1041]. 13. Kang SS, Labropoulos N, Mansour MA, Michelini M, Filliung D, Baubly MP, et al. Expanded indications for ultrasound-guided thrombin injection of pseudoaneurysms. J Vasc Surg. 2000;31:289-298. 14. Patel M, Tchelepi H, Rice DH. Traumatic pseudoaneurysm of the occipital artery: case report and review of the literature. Ear Nose Throat J. 2008;87:E7-E12.
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 20 April 2016; accepted 29 September 2016 Citation: World Neurosurg. (2016). http://dx.doi.org/10.1016/j.wneu.2016.09.116 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2016 Elsevier Inc. All rights reserved.
www.WORLDNEUROSURGERY.org
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Ruptured Aneurysms of the Occipital Artery Associated with Congenital Occipital Bone Defect Toshinari Kawasaki, Kazumichi Yoshida, Takayuki Kikuchi, Akira Ishii, Yasushi Takagi, Susumu Miyamoto
Key words Bone defect - Meningoencephalocele - Occipital artery - Traumatic aneurysm -
- BACKGROUND:
Traumatic aneurysms of the superficial temporal artery have been frequently reported in the literature, whereas traumatic aneurysms of the occipital artery (OA) are extremely rare.
- CASE
Abbreviations and Acronyms CT: Computed tomography ECA: External carotid artery NBCA: N-butyl-2-cyanoacrylate OA: Occipital artery STA: Superficial temporal artery Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan To whom correspondence should be addressed: Kazumichi Yoshida, M.D., Ph.D. [E-mail: [email protected]] Citation: World Neurosurg. (2016). http://dx.doi.org/10.1016/j.wneu.2016.09.116 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2016 Elsevier Inc. All rights reserved.
INTRODUCTION Aneurysms of the external carotid artery (ECA) can be caused by several mechanisms such as traumatic injury,1-4 infection,5 or iatrogenesis.6 Traumatic aneurysms of the superficial temporal artery (STA) have been frequently reported in the literature, whereas traumatic aneurysms of the occipital artery (OA) are extremely rare. We report the first case of traumatic ruptured aneurysms of the OA associated with meningoencephalocele caused by a congenital occipital bone defect.
CASE DESCRIPTION A 30-year-old man was emergently admitted to our hospital with the chief complaint of sudden neck swelling and pain during a football game. Initial computed tomography (CT) showed a large meningoencephalocele protruding from his occipital bone defect and a hematoma in his right neck, which rapidly increased in volume on follow-up CTs. His
DESCRIPTION: A 30-year-old man had been followed at another hospital for meningoencephalocele associated with his congenital occipital bone defect. He was admitted to our hospital with a chief complaint of neck swelling and pain during a football game. Computed tomography and magnetic resonance imaging showed a hematoma in his right neck along with the meningoencephalocele. In addition, it showed an atrophic cerebellum with a cyst protruding from his occipital bone defect. Digital subtraction angiography of the right OA showed 3 aneurysms responsible for the large hematoma in his neck. Endovascular embolization with 20% N-butyl-2-cyanoacrylate was performed for treatment of the ruptured aneurysms followed by emergent surgical evacuation of the hematoma. An occipital cranioplasty with titanium mesh was performed 10 months after the emergent intervention.
- CONCLUSIONS:
In this patient, the congenital occipital bone defect with meningoencephalocele might have been the remote source of risk for traumatic pseudoaneurysms along the muscle branches of the OA.
meningoencephalocele was initially diagnosed at another hospital when he was 3 years old, and a conservative approach with follow-up CTs had been taken until he reached adulthood. On admission to our hospital, his right neck was soft, reddened, and swollen but without a pulsatile nodule. Epidermolysis associated with purpura was confirmed on the surface of the neck. Blood examination showed slight evidence of an inflammatory reaction (white blood cell count, 12,400/mL; C-reactive protein level, 4.9 mg/dL) and anemia (hemoglobin level, 10.1 g/dL), although his immune reaction and coagulation tests were normal. Threedimensional CT of the bone (Figure 1) and magnetic resonance imaging (Figure 2) showed the large occipital bone defect and the hematoma in his right neck and meningoencephalocele, respectively. Digital subtraction angiography was performed to probe for causes of the hematoma in detail. Digital subtraction angiography showed 3 aneurysms in the branches of the right OA (Figure 3A).
WORLD NEUROSURGERY -: ---, MONTH 2016
Endovascular embolization with 20% N-butyl-2-cyanoacrylate (NBCA) was performed for obliteration of the aneurysms, which successfully restricted continued hemorrhage (Figure 3B). Because his neck swelling and the tension of his skin were still severe at the end of the endovascular intervention, surgical evacuation of the neck hematoma was subsequently performed under general anesthesia. The patient’s postoperative course was uneventful, and he was discharged from our hospital 30 days after admission. An occipital titanium mesh cranioplasty was performed 10 months after the emergent intervention both for cosmetic reasons and to prevent against future traumatic aneurysm formation. DISCUSSION Most traumatic aneurysms at the branches of the ECA are associated with contact sports and blunt trauma.1-4 Traumatic pseudoaneurysm formation usually takes
www.WORLDNEUROSURGERY.org
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CASE REPORT TOSHINARI KAWASAKI ET AL.
RUPTURED ANEURYSMS OF THE OA
Figure 3. (A) Three pseudoaneurysms (arrows) are confirmed by selective digital subtraction angiography of the right occipital artery. (B) All of the pseudoaneurysms have been completely obliterated by endovascular embolization using 20% N-butyl-2-cyanoacrylate.
Figure 1. An extensive occipital bone defect is clearly shown on three-dimensional computed tomography with bone windows.
2e6 weeks after external injury.7 Infectious5 and iatrogenic6 causes of ECA aneurysms have been infrequently reported in the literature. According to reports evaluating the pathologic findings of ECA aneurysms, pseudoaneurysm is more frequent than true aneurysm.8,9 Based on the analysis of 386 traumatic ECA aneurysms, Conner et al.7 reported
327 aneurysms of the STA, 27 of the internal maxillary artery, 26 of the facial artery, 2 of the OA, 2 of the lingual artery, 2 of the superior thyroid artery, and 1 of the supraorbital artery. The STA, internal maxillary artery, and facial artery are all susceptible to blunt trauma because these arteries are not protected by bone and soft tissue, which might explain the high incidence of traumatic ECA aneurysms of these arteries. To the best of our knowledge, this is the first case of multiple traumatic ruptured aneurysms of the OA in the setting of a
Figure 2. Axial (left) and coronal (right) T1-weighted magnetic resonance images show an atrophic cerebellum with a large cyst protruding through the bone defect. Extensive hematoma in the patient’s right neck is also confirmed by the coronal image (right).
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www.SCIENCEDIRECT.com
meningoencephalocele associated with a congenital occipital bone defect. During development, the occipital bone defect might have caused atrophy and vulnerability of the cervical supportive muscles attached to the occipital bone. The skin covering the meningoencephalocele was noted to be extended and thinned. Under those circumstances, the protective ability of the skin might have been reduced because of secondary structural changes such as hemorrhage, ulceration, and epithelization. Thus, mild blunt trauma to his neck could more easily result in the formation of multiple aneurysms. Conservative treatment of the meningoencephalocele and occipital bone defect without cranioplasty might have indirectly influenced the formation of multiple aneurysms in this patient. The reported options for treatment of ECA aneurysm are surgical resection,2,4-6,10 endovascular coil embolization,3,11 embolization with thrombin,12,13 and external compression with an echo duplex probe.1,14 Although embolization with thrombin using ultrasonography is convenient and minimally invasive, it has some disadvantages such as recanalization, allergic reaction, and ischemic complications. Vogelaere et al.6 reported that surgical resection was performed for a traumatic STA aneurysm after unsuccessful external compression with a duplex probe. In our patient, multiple aneurysms of the OA were obliterated by endovascular embolization with NBCA and the large
WORLD NEUROSURGERY, http://dx.doi.org/10.1016/j.wneu.2016.09.116
CASE REPORT TOSHINARI KAWASAKI ET AL.
RUPTURED ANEURYSMS OF THE OA
hematoma in the neck was surgically evacuated, which led to a favorable result.
4. Lalak NJ, Farmer E. Traumatic pseudoaneurysm of the superficial temporal artery associated with facial nerve palsy. J Cardiovasc Surg (Torino). 1996;37:119-123.
CONCLUSIONS
5. Forbes TL, Tong M. External carotid artery pseudoaneurysm in an immunocompromised patient. Can J Surg. 2008;51:E11-E12.
We describe the first case of traumatic multiple ruptured aneurysms of the OA associated with meningoencephalocele caused by a congenital occipital bone defect that might have been a remote cause of aneurysm formation. Emergent endovascular embolization with NBCA for the aneurysms, followed by surgical evacuation of the hematoma and elective occipital cranioplasty, were performed. REFERENCES 1. De Vogelaere K. Traumatic aneurysm of the superficial temporal artery: case report. J Trauma. 2004;57:399-401. 2. Fox JT, Cordts PR, Gwinn BC 2nd. Traumatic aneurysm of the superficial temporal artery: case report. J Trauma. 1994;36:562-564. 3. Hong JT, Lee SW, Ihn YK, Son BC, Sung JH, Kim IS, et al. Traumatic pseudoaneurysm of the superficial temporal artery treated by endovascular coil embolization. Surg Neurol. 2006;66:86-88.
6. Angevine PD, Connolly ES Jr. Pseudoaneurysms of the superficial temporal artery secondary to placement of external ventricular drainage catheters. Surg Neurol. 2002;58:258-260. 7. Conner WC 3rd, Rohrich RJ, Pollock RA. Traumatic aneurysms of the face and temple: a patient report and literature review, 1644 to 1998. Ann Plast Surg. 1998;41:321-326. 8. Kim HS, Son BC, Lee SW, Kim IS. A rare case of spontaneous true aneurysm of the occipital artery. J Korean Neurosurg Soc. 2010;47:310-312. 9. Rao VY, Hwang SW, Adesina AM, Jea A. Thrombosed traumatic aneurysm of the occipital artery: a case report and review of the literature. J Med Case Rep. 2012;6:203. 10. Campbell AS, Butler AP, Grandas OH. A case of external carotid artery pseudoaneurysm from hyoid bone fracture. Am Surg. 2003;69:534-535. 11. Mendez JC, Sendra J, Poveda P, Garcia-Leal R. Endovascular treatment of traumatic aneurysm of
WORLD NEUROSURGERY -: ---, MONTH 2016
the occipital artery. Cardiovasc Intervent Radiol. 2006; 29:486-487. 12. Bobinski L, Bostrom S, Hillman J, Theodorsson A. Postoperative pseudoaneurysm of the superficial temporal artery (S.T.A.) treated with Thrombostat (thrombin glue) injection. Acta Neurochir (Wien). 2004;146:1039-1041 [discussion: 1041]. 13. Kang SS, Labropoulos N, Mansour MA, Michelini M, Filliung D, Baubly MP, et al. Expanded indications for ultrasound-guided thrombin injection of pseudoaneurysms. J Vasc Surg. 2000;31:289-298. 14. Patel M, Tchelepi H, Rice DH. Traumatic pseudoaneurysm of the occipital artery: case report and review of the literature. Ear Nose Throat J. 2008;87:E7-E12.
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 20 April 2016; accepted 29 September 2016 Citation: World Neurosurg. (2016). http://dx.doi.org/10.1016/j.wneu.2016.09.116 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2016 Elsevier Inc. All rights reserved.
www.WORLDNEUROSURGERY.org
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