- Email: [email protected]
Subdural Hematoma from a Cavernous Malformation
Peer-Review Short Reports
Subdural Hematoma from a Cavernous Malformation Anne J. Schmitt1, Alim P. Mitha2, Rasha Germain2, Jennifer Eschbacher3, Robert F. Spetzler2
Key words Cavernous malformation - Subdural hematoma -
- OBJECTIVE:
To present a case of a cavernous malformation presenting with a subdural hematoma.
- METHODS:
To whom correspondence should be addressed: Robert F. Spetzler, M.D. [E-mail: [email protected]]
A 27-year-old woman was admitted with progressively worsening headache, vomiting, weakness, and word-finding difficulties 1 week after she was discharged from an outside hospital, where she was managed conservatively for a presumed traumatic subdural hematoma. Computed tomography revealed an enlarging subacute left hemispheric subdural hematoma for which she underwent drill craniostomy. Postprocedural magnetic resonance imaging showed a posterior left temporal lobe mass consistent with a cavernous malformation juxtaposed with the subdural hematoma. Craniotomy for resection of the lesion was performed. She had an uncomplicated postoperative course and experienced a good recovery.
Citation: World Neurosurg. (2013). http://dx.doi.org/10.1016/j.wneu.2013.01.018
- RESULTS:
Abbreviation and Acronym MRI: Magnetic resonance imaging From the 1Department of Neurosurgery, John Radcliffe Hospital, Oxford, United Kingdom; and Divisions of 2 Neurological Surgery and 3Neuropathology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona, USA
Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2013 Elsevier Inc. All rights reserved.
INTRODUCTION Cavernous malformations, also called cavernous angiomas or cavernomas, are vascular malformations in the central nervous system consisting of irregularly enlarged capillaries containing a single layer of endothelium. They are low-flow lesions that usually are found incidentally in asymptomatic patients. Their size ranges from a few millimeters to several centimeters. The lesions may grow over time and, if so, patients tend to become symptomatic between their second and fifth decades of life. A cavernous malformation that bleeds can cause small intraparenchymal hemorrhages. The risk of hemorrhage is considered to be 2.6%e3.2% per year (11). Symptoms are related to the location of the hemorrhage. We describe the case of a patient with a temporal lobe cavernous malformation that manifested with a subdural hematoma. CASE REPORT A 27-year-old woman was admitted to an outside hospital after experiencing a seizure and a ground-level fall. One week before her seizure, she had complained of nausea and headaches. She was found to
The signs and symptoms, diagnostic imaging, and intraoperative findings suggest that the subdural hematoma was caused by extralesional hemorrhage of the cavernous malformation, which is a rare finding associated with these malformations.
- CONCLUSIONS:
The clinical course, radiologic, and intraoperative findings suggest that the subdural hemorrhage was caused by extralesional hemorrhage of the cavernous malformation.
have an acute, moderately sized left subdural hematoma along the tentorium and frontotemporal and parietal regions of the brain but with minimal subfalcine herniation. She was managed conservatively for several days, started on antiepileptic drugs, and discharged home after symptomatic improvement. One week later she sought treatment for worsening left-sided headache, nausea, vomiting, and moderate word-finding difficulty. Her family also reported personality changes and a decrease in her short-term memory. On physical examination she was expressively aphasic and showed a slight motor deficit in her right upper extremity that manifested with a pronator drift. She was otherwise neurologically intact. Her medical history was positive for alcohol abuse, but she denied using alcohol since her initial fall. Her liver function tests showed slight abnormalities; her coagulation parameters were within the physiologic range. Computed tomography showed a 1-cm thick left hemispheric mixed acute and
WORLD NEUROSURGERY - (-): ---, MONTH 2013
subacute subdural hematoma causing 1 cm of rightward midline shift. She underwent a twist drill craniostomy to relieve her symptoms. However, her symptoms persisted, and she underwent magnetic resonance imaging (MRI) of her brain. A 1.1-cm mass was found in the posterior left temporal lobe with a rim of T1- and T2weighted hypointensity consistent with a cavernous malformation (Figure 1). After the lesion was identified, the patient underwent an uncomplicated craniotomy to evacuate the residual subdural hematoma and to resect the cavernous malformation. Intraoperatively, a subacute-to-chronic subdural hematoma with organized membranes exerting mass effect was discovered in the left posterior temporal lobe. Intraoperative image guidance was performed using the StealthStation Surgical Navigation System (Medtronic, Minneapolis, Minnesota, USA). Despite brain shift in this case, the neuronavigation was accurate and facilitated locating and identifying the lesion. The intra-axial lesion was noted to
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1.E1
PEER-REVIEW SHORT REPORTS ANNE J. SCHMITT ET AL.
SDH FROM A CAVERNOUS MALFORMATION
Figure 1. (A) Coronal T2-weighted magnetic resonance imaging (MRI) showing the left temporal cavernous malformation abutting the subdural hemorrhage. (B) Axial T1-weighted MRI showing the left temporal cavernous malformation with the adjacent subdural hematoma encompassing the frontotemporal lobe. (Used with permission from Barrow Neurological Institute.)
be surrounded by hemosiderin-stained tissue (Figure 2A). The staining extended to the cortical surface. More diffuse hemosiderin staining was present in the adjacent cortical subarachnoid spaces (Figure 2B). The contents of the cavernous malformation were conspicuously similar to the subdural hematoma. Histological examination of the surgical specimen showed large, thin-walled blood vessels that lacked smooth muscle or an internal elastic lamina, consistent with a cavernous malformation (Figure 3). Postoperative imaging confirmed complete resection of the lesion. The patient experienced a good recovery and was
discharged on the fourth postoperative day with improved symptoms. On her 14th postoperative day, she was seen for a follow-up examination as an outpatient. At that time, she had only subtle wordfinding difficulties and no other neurological deficits. DISCUSSION The incidence of cavernous malformations in the general population ranges between 0.37% and 0.8 % (1, 10). After developmental venous anomalies, cavernous malformations are the second most common type of vascular malformation and account
Figure 2. (A) Intraoperative photograph showing the subacute subdural hematoma and subarachnoid hemorrhage, with similar hemosiderin staining at the adjacent cavernous malformation. (B) Intraoperative photograph showing the typical macroscopic features of the cavernous malformation, including the classic “mulberry” appearance. (Used with permission from Barrow Neurological Institute.)
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for 10%e15% of all vascular malformations in the central nervous system (5, 9). Most lesions occur sporadically, but familial cavernous malformations account for 6% of all lesions and are inherited in an autosomal-dominant pattern (5). Clinical findings in symptomatic patients include nonspecific headaches, focal neurologic deficits, and seizures. Approximately 50%e 70% of all people with cerebral cavernous malformations experience symptoms (6). Hemorrhage occurs in as many as 56% of symptomatic patients with a cavernous malformation. The most common type of hemorrhage is intralesional; extralesional hemorrhages rarely occur (7). Hemorrhages usually occur intraparenchymally, and few cases of cavernous malformation manifesting as subdural hemorrhages have been reported (4, 13, 15). Cavernous malformations are usually diagnosed by MRI studies. On T1-weighted MRI, cavernous malformations present as heterogeneously intense lesions. On T2weighted MRI, a perilesional hypointense rim caused by hemosiderin deposition in the surrounding tissue is visible. Blooming artifact on gradient-echo MRI sequences is also characteristic (3, 12). Computed tomography is less sensitive than MRI for the detection of cavernous malformations, and small lesions can easily be missed with this imaging modality. Although a cavernous malformation presenting as a subdural hematoma is extremely uncommon, we strongly suspect that the subdural hematoma in our patient resulted from bleeding of her cavernous malformation. Subdural hematomas can be subdivided into acute and chronic subdural hematomas. Acute subdural hematomas are caused by cerebral acceleration-deceleration, which causes the surface of bridging veins to rupture, leading to an accumulation of blood in the subdural space. In contrast, chronic subdural hematomas are associated with trauma (often trivial trauma) in fewer than 50% of cases and usually occur in elderly patients. Risk factors for chronic subdural hematoma are the presence of coagulopathies, seizures, alcohol abuse, and cerebrospinal fluid shunts (2, 8, 14). The acute component of the subdural hematoma noted at the outside hospital could have been related to bleeding of the cavernous malformation at the time of the patient’s ground-level fall or related to the
WORLD NEUROSURGERY, http://dx.doi.org/10.1016/j.wneu.2013.01.018
PEER-REVIEW SHORT REPORTS ANNE J. SCHMITT ET AL.
SDH FROM A CAVERNOUS MALFORMATION
DL, eds. Cavernous Malformations. Park Ridge, IL: AANS; 1993:13-23. 6. Morrison L, Akers A: Cerebral Cavernous Malformation, Familial. 2006. Available at: http:// www.ncbi.nlm.nih.gov/books/NBK1293/#top. Accessed February 6, 2013. 7. Kupersmith MJ, Kalish H, Epstein F, Yu G, Berenstein A, Woo H, Jafar J, Mandel G, De Lara F: Natural history of brainstem cavernous malformations. Neurosurgery 48:47-53, 2001. 8. Lee KS: Natural history of chronic subdural haematoma. Brain Inj 18:351-358, 2004. Figure 3. (A) Histopathological slide from the surgical specimen showing a network of thin-walled blood vessels that lack smooth muscle or an internal elastic lamina, consistent with a cavernous malformation. The arrow demonstrates a thrombosed blood vessel. (B) Histopathological slide showing numerous macrophages, some of which contain blood products, consistent with reactive changes secondary to chronic hemorrhage. (Used with permission from Barrow Neurological Institute.)
trauma itself. However, her intraoperative findings showed old hemosiderin, providing further evidence that the subdural hematoma likely evolved during a longer period of time than could be accounted for by the patient’s history of trauma 1 week before her presentation. Furthermore, the age of blood found in the subdural space showed similar features to the hemorrhagic contents of the cavernous malformation, and the lesion extended to the surface of the brain directly adjacent to the subdural hematoma. Typically, cavernous malformations cause small intralesional hemorrhages because of the absence of a connection to the high-flow vascular system. In this case, however, the proximity of this lesion to the cortical surface likely offered a path of low resistance and predisposed the patient to a large extralesional (and, in this case, subdural) hemorrhage. These findings, as well as the fact that the patient complained of neurological symptoms the week before she fell, suggest that the cavernous malformation was the cause of her subdural hematoma.
In patients with no history of trauma or coagulopathy, however, cavernous malformations should be included in the differential diagnosis. Doing so is especially important when treating patients with poorly investigated epilepsy. Furthermore, the clinician should be aware of the natural history of subdural hematomas, pressure relationships, and dynamics of bleeding events because some patients who do not follow a classic course may need further investigations. REFERENCES 1. Del CO Jr, Kelly DL Jr, Elster AD, Craven TE: An analysis of the natural history of cavernous angiomas. J Neurosurg 75:702-708, 1991. 2. Ducruet AF, Grobelny BT, Zacharia BE, Hickman ZL, DeRosa PL, Anderson K, Sussman E, Carpenter A, Connolly ES Jr: The surgical management of chronic subdural hematoma. Neurosurg Rev 35:155-169, 2012. 3. Feng J, Xu YK, Li L, Yang RM, Ye XH, Zhang N, Yu T, Lin BQ: MRI diagnosis and preoperative evaluation for pure epidural cavernous hemangiomas. Neuroradiology 51:741-747, 2009.
9. Maraire JN, Awad IA: Intracranial cavernous malformations: lesion behavior and management strategies. Neurosurgery 37:591-605, 1995. 10. McCormick WF: Pathology of Vascular Malformations of the Brain, Intracranial Arteriovenous Malformations. Baltimore: Williams & Wilkins; 1984:44-63. 11. Moriarity JL, Clatterbuck RE, Rigamonti D: The natural history of cavernous malformations. Neurosurg Clin N Am 10:411-417, 1999. 12. Rigamonti D, Drayer BP, Johnson PC, Hadley MN, Zabramski J, Spetzler RF: The MRI appearance of cavernous malformations (angiomas). J Neurosurg 67:518-524, 1987. 13. Suzuki K, Kamezaki T, Tsuboi K, Kobayashi E: Dural cavernous angioma causing acute subdural hemorrhage—case report. Neurol Med Chir (Tokyo) 36:580-582, 1996. 14. Tang J, Ai J, Macdonald RL: Developing a model of chronic subdural hematoma. Acta Neurochir Suppl 111:25-29, 2011. 15. Torne HL, Martin MJ, Ara Callizo JR: Cavernous hemangioma of the frontal bone with subdural hematoma [in Spanish]. Neurologia 24:141-142, 2009.
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 13 July 2012; accepted 4 January 2013 Citation: World Neurosurg. (2013). http://dx.doi.org/10.1016/j.wneu.2013.01.018
CONCLUSIONS
4. Gottfried ON, Gluf WM, Schmidt MH: Cavernous hemangioma of the skull presenting with subdural hematoma. Case report. Neurosurg Focus 17:ECP1, 2004.
Hemorrhage of a cavernous malformation rarely manifests as a subdural hematoma.
5. Hsu FP, Rigamonti D, Huhn SL: Epidemiology of cavernous malformations. In: Awad IA, Barrow
1878-8750/$ - see front matter ª 2013 Elsevier Inc. All rights reserved.
WORLD NEUROSURGERY - (-): ---, MONTH 2013
Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com
www.WORLDNEUROSURGERY.org
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Subdural Hematoma from a Cavernous Malformation Anne J. Schmitt1, Alim P. Mitha2, Rasha Germain2, Jennifer Eschbacher3, Robert F. Spetzler2
Key words Cavernous malformation - Subdural hematoma -
- OBJECTIVE:
To present a case of a cavernous malformation presenting with a subdural hematoma.
- METHODS:
To whom correspondence should be addressed: Robert F. Spetzler, M.D. [E-mail: [email protected]]
A 27-year-old woman was admitted with progressively worsening headache, vomiting, weakness, and word-finding difficulties 1 week after she was discharged from an outside hospital, where she was managed conservatively for a presumed traumatic subdural hematoma. Computed tomography revealed an enlarging subacute left hemispheric subdural hematoma for which she underwent drill craniostomy. Postprocedural magnetic resonance imaging showed a posterior left temporal lobe mass consistent with a cavernous malformation juxtaposed with the subdural hematoma. Craniotomy for resection of the lesion was performed. She had an uncomplicated postoperative course and experienced a good recovery.
Citation: World Neurosurg. (2013). http://dx.doi.org/10.1016/j.wneu.2013.01.018
- RESULTS:
Abbreviation and Acronym MRI: Magnetic resonance imaging From the 1Department of Neurosurgery, John Radcliffe Hospital, Oxford, United Kingdom; and Divisions of 2 Neurological Surgery and 3Neuropathology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona, USA
Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2013 Elsevier Inc. All rights reserved.
INTRODUCTION Cavernous malformations, also called cavernous angiomas or cavernomas, are vascular malformations in the central nervous system consisting of irregularly enlarged capillaries containing a single layer of endothelium. They are low-flow lesions that usually are found incidentally in asymptomatic patients. Their size ranges from a few millimeters to several centimeters. The lesions may grow over time and, if so, patients tend to become symptomatic between their second and fifth decades of life. A cavernous malformation that bleeds can cause small intraparenchymal hemorrhages. The risk of hemorrhage is considered to be 2.6%e3.2% per year (11). Symptoms are related to the location of the hemorrhage. We describe the case of a patient with a temporal lobe cavernous malformation that manifested with a subdural hematoma. CASE REPORT A 27-year-old woman was admitted to an outside hospital after experiencing a seizure and a ground-level fall. One week before her seizure, she had complained of nausea and headaches. She was found to
The signs and symptoms, diagnostic imaging, and intraoperative findings suggest that the subdural hematoma was caused by extralesional hemorrhage of the cavernous malformation, which is a rare finding associated with these malformations.
- CONCLUSIONS:
The clinical course, radiologic, and intraoperative findings suggest that the subdural hemorrhage was caused by extralesional hemorrhage of the cavernous malformation.
have an acute, moderately sized left subdural hematoma along the tentorium and frontotemporal and parietal regions of the brain but with minimal subfalcine herniation. She was managed conservatively for several days, started on antiepileptic drugs, and discharged home after symptomatic improvement. One week later she sought treatment for worsening left-sided headache, nausea, vomiting, and moderate word-finding difficulty. Her family also reported personality changes and a decrease in her short-term memory. On physical examination she was expressively aphasic and showed a slight motor deficit in her right upper extremity that manifested with a pronator drift. She was otherwise neurologically intact. Her medical history was positive for alcohol abuse, but she denied using alcohol since her initial fall. Her liver function tests showed slight abnormalities; her coagulation parameters were within the physiologic range. Computed tomography showed a 1-cm thick left hemispheric mixed acute and
WORLD NEUROSURGERY - (-): ---, MONTH 2013
subacute subdural hematoma causing 1 cm of rightward midline shift. She underwent a twist drill craniostomy to relieve her symptoms. However, her symptoms persisted, and she underwent magnetic resonance imaging (MRI) of her brain. A 1.1-cm mass was found in the posterior left temporal lobe with a rim of T1- and T2weighted hypointensity consistent with a cavernous malformation (Figure 1). After the lesion was identified, the patient underwent an uncomplicated craniotomy to evacuate the residual subdural hematoma and to resect the cavernous malformation. Intraoperatively, a subacute-to-chronic subdural hematoma with organized membranes exerting mass effect was discovered in the left posterior temporal lobe. Intraoperative image guidance was performed using the StealthStation Surgical Navigation System (Medtronic, Minneapolis, Minnesota, USA). Despite brain shift in this case, the neuronavigation was accurate and facilitated locating and identifying the lesion. The intra-axial lesion was noted to
www.WORLDNEUROSURGERY.org
1.E1
PEER-REVIEW SHORT REPORTS ANNE J. SCHMITT ET AL.
SDH FROM A CAVERNOUS MALFORMATION
Figure 1. (A) Coronal T2-weighted magnetic resonance imaging (MRI) showing the left temporal cavernous malformation abutting the subdural hemorrhage. (B) Axial T1-weighted MRI showing the left temporal cavernous malformation with the adjacent subdural hematoma encompassing the frontotemporal lobe. (Used with permission from Barrow Neurological Institute.)
be surrounded by hemosiderin-stained tissue (Figure 2A). The staining extended to the cortical surface. More diffuse hemosiderin staining was present in the adjacent cortical subarachnoid spaces (Figure 2B). The contents of the cavernous malformation were conspicuously similar to the subdural hematoma. Histological examination of the surgical specimen showed large, thin-walled blood vessels that lacked smooth muscle or an internal elastic lamina, consistent with a cavernous malformation (Figure 3). Postoperative imaging confirmed complete resection of the lesion. The patient experienced a good recovery and was
discharged on the fourth postoperative day with improved symptoms. On her 14th postoperative day, she was seen for a follow-up examination as an outpatient. At that time, she had only subtle wordfinding difficulties and no other neurological deficits. DISCUSSION The incidence of cavernous malformations in the general population ranges between 0.37% and 0.8 % (1, 10). After developmental venous anomalies, cavernous malformations are the second most common type of vascular malformation and account
Figure 2. (A) Intraoperative photograph showing the subacute subdural hematoma and subarachnoid hemorrhage, with similar hemosiderin staining at the adjacent cavernous malformation. (B) Intraoperative photograph showing the typical macroscopic features of the cavernous malformation, including the classic “mulberry” appearance. (Used with permission from Barrow Neurological Institute.)
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www.SCIENCEDIRECT.com
for 10%e15% of all vascular malformations in the central nervous system (5, 9). Most lesions occur sporadically, but familial cavernous malformations account for 6% of all lesions and are inherited in an autosomal-dominant pattern (5). Clinical findings in symptomatic patients include nonspecific headaches, focal neurologic deficits, and seizures. Approximately 50%e 70% of all people with cerebral cavernous malformations experience symptoms (6). Hemorrhage occurs in as many as 56% of symptomatic patients with a cavernous malformation. The most common type of hemorrhage is intralesional; extralesional hemorrhages rarely occur (7). Hemorrhages usually occur intraparenchymally, and few cases of cavernous malformation manifesting as subdural hemorrhages have been reported (4, 13, 15). Cavernous malformations are usually diagnosed by MRI studies. On T1-weighted MRI, cavernous malformations present as heterogeneously intense lesions. On T2weighted MRI, a perilesional hypointense rim caused by hemosiderin deposition in the surrounding tissue is visible. Blooming artifact on gradient-echo MRI sequences is also characteristic (3, 12). Computed tomography is less sensitive than MRI for the detection of cavernous malformations, and small lesions can easily be missed with this imaging modality. Although a cavernous malformation presenting as a subdural hematoma is extremely uncommon, we strongly suspect that the subdural hematoma in our patient resulted from bleeding of her cavernous malformation. Subdural hematomas can be subdivided into acute and chronic subdural hematomas. Acute subdural hematomas are caused by cerebral acceleration-deceleration, which causes the surface of bridging veins to rupture, leading to an accumulation of blood in the subdural space. In contrast, chronic subdural hematomas are associated with trauma (often trivial trauma) in fewer than 50% of cases and usually occur in elderly patients. Risk factors for chronic subdural hematoma are the presence of coagulopathies, seizures, alcohol abuse, and cerebrospinal fluid shunts (2, 8, 14). The acute component of the subdural hematoma noted at the outside hospital could have been related to bleeding of the cavernous malformation at the time of the patient’s ground-level fall or related to the
WORLD NEUROSURGERY, http://dx.doi.org/10.1016/j.wneu.2013.01.018
PEER-REVIEW SHORT REPORTS ANNE J. SCHMITT ET AL.
SDH FROM A CAVERNOUS MALFORMATION
DL, eds. Cavernous Malformations. Park Ridge, IL: AANS; 1993:13-23. 6. Morrison L, Akers A: Cerebral Cavernous Malformation, Familial. 2006. Available at: http:// www.ncbi.nlm.nih.gov/books/NBK1293/#top. Accessed February 6, 2013. 7. Kupersmith MJ, Kalish H, Epstein F, Yu G, Berenstein A, Woo H, Jafar J, Mandel G, De Lara F: Natural history of brainstem cavernous malformations. Neurosurgery 48:47-53, 2001. 8. Lee KS: Natural history of chronic subdural haematoma. Brain Inj 18:351-358, 2004. Figure 3. (A) Histopathological slide from the surgical specimen showing a network of thin-walled blood vessels that lack smooth muscle or an internal elastic lamina, consistent with a cavernous malformation. The arrow demonstrates a thrombosed blood vessel. (B) Histopathological slide showing numerous macrophages, some of which contain blood products, consistent with reactive changes secondary to chronic hemorrhage. (Used with permission from Barrow Neurological Institute.)
trauma itself. However, her intraoperative findings showed old hemosiderin, providing further evidence that the subdural hematoma likely evolved during a longer period of time than could be accounted for by the patient’s history of trauma 1 week before her presentation. Furthermore, the age of blood found in the subdural space showed similar features to the hemorrhagic contents of the cavernous malformation, and the lesion extended to the surface of the brain directly adjacent to the subdural hematoma. Typically, cavernous malformations cause small intralesional hemorrhages because of the absence of a connection to the high-flow vascular system. In this case, however, the proximity of this lesion to the cortical surface likely offered a path of low resistance and predisposed the patient to a large extralesional (and, in this case, subdural) hemorrhage. These findings, as well as the fact that the patient complained of neurological symptoms the week before she fell, suggest that the cavernous malformation was the cause of her subdural hematoma.
In patients with no history of trauma or coagulopathy, however, cavernous malformations should be included in the differential diagnosis. Doing so is especially important when treating patients with poorly investigated epilepsy. Furthermore, the clinician should be aware of the natural history of subdural hematomas, pressure relationships, and dynamics of bleeding events because some patients who do not follow a classic course may need further investigations. REFERENCES 1. Del CO Jr, Kelly DL Jr, Elster AD, Craven TE: An analysis of the natural history of cavernous angiomas. J Neurosurg 75:702-708, 1991. 2. Ducruet AF, Grobelny BT, Zacharia BE, Hickman ZL, DeRosa PL, Anderson K, Sussman E, Carpenter A, Connolly ES Jr: The surgical management of chronic subdural hematoma. Neurosurg Rev 35:155-169, 2012. 3. Feng J, Xu YK, Li L, Yang RM, Ye XH, Zhang N, Yu T, Lin BQ: MRI diagnosis and preoperative evaluation for pure epidural cavernous hemangiomas. Neuroradiology 51:741-747, 2009.
9. Maraire JN, Awad IA: Intracranial cavernous malformations: lesion behavior and management strategies. Neurosurgery 37:591-605, 1995. 10. McCormick WF: Pathology of Vascular Malformations of the Brain, Intracranial Arteriovenous Malformations. Baltimore: Williams & Wilkins; 1984:44-63. 11. Moriarity JL, Clatterbuck RE, Rigamonti D: The natural history of cavernous malformations. Neurosurg Clin N Am 10:411-417, 1999. 12. Rigamonti D, Drayer BP, Johnson PC, Hadley MN, Zabramski J, Spetzler RF: The MRI appearance of cavernous malformations (angiomas). J Neurosurg 67:518-524, 1987. 13. Suzuki K, Kamezaki T, Tsuboi K, Kobayashi E: Dural cavernous angioma causing acute subdural hemorrhage—case report. Neurol Med Chir (Tokyo) 36:580-582, 1996. 14. Tang J, Ai J, Macdonald RL: Developing a model of chronic subdural hematoma. Acta Neurochir Suppl 111:25-29, 2011. 15. Torne HL, Martin MJ, Ara Callizo JR: Cavernous hemangioma of the frontal bone with subdural hematoma [in Spanish]. Neurologia 24:141-142, 2009.
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 13 July 2012; accepted 4 January 2013 Citation: World Neurosurg. (2013). http://dx.doi.org/10.1016/j.wneu.2013.01.018
CONCLUSIONS
4. Gottfried ON, Gluf WM, Schmidt MH: Cavernous hemangioma of the skull presenting with subdural hematoma. Case report. Neurosurg Focus 17:ECP1, 2004.
Hemorrhage of a cavernous malformation rarely manifests as a subdural hematoma.
5. Hsu FP, Rigamonti D, Huhn SL: Epidemiology of cavernous malformations. In: Awad IA, Barrow
1878-8750/$ - see front matter ª 2013 Elsevier Inc. All rights reserved.
WORLD NEUROSURGERY - (-): ---, MONTH 2013
Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com
www.WORLDNEUROSURGERY.org
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