Surg Neurol 1992;38:341-6
341
Ruptured Suprasellar Dermoid Associated with Middle Cerebral Artery Aneurysm: Case Report Ishtiaq Ahmad, M.B.B.S., Teiji Tominaga, M.D., Akira Ogawa, M.D., and Takashi Yoshimoto, M.D. Division of Neurosurgery, Institute of Brain Diseases, Tohoku University School of Medicine, Sendai, Japan
Ahmad I, Tominaga T, Ogawa A, Yoshimoto T. Ruptured suprasellar dermoid associated with middle cerebral artery aneurysm: case report. Surg Neurol 1992;38:341-6.
Dermoid tumor associated with cerebral aneurysm is extremely rare. We report here a case of ruptured suprasellar dermoid cyst associated with middle cerebral artery (M1) aneurysm and stenosis of adjacent arterial trunks. The characteristic feature of this association is the tight adhesion of the vascular lesion to the tumor capsule. KEY WORDS: Dermoid; Epidermoid; MCA aneurysm; Magnetic resonance imaging
Epidermoid or dermoid tumor with cerebral aneurysm is a rare association. In reviewing the literature, over 140 cases of brain tumor associated with cerebral aneurysm have been reported [4,6,10,13,16,17 ]. However, in only two cases were epidermoid tumors associated with aneurysm [10,16]. Association o f dermoid with cerebral aneurysm has not been described previously. H e r e we report a case o f suprasellar dermoid associated with middle cerebral artery (MCA) aneurysm and stenosis o f adjacent arterial trunks. Based on the operative findings, the pathogenesis of this rare association is briefly discussed.
Case Report A 21-year-old woman was referred to a local hospital with the complaint of headache and nausea in June 1985. A computed tomographic (CT) scan revealed a low-density area in the right middle cranial fossa, and she was diagnosed as having an arachnoid cyst. Beginning in 1986, she complained of attacks o f loss o f consciousness,
Address reprint requests to: I. Ahmad, M.B.B.S., Division of Neurosurgery, Institute of Brain Diseases, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980, Japan. Received June 15, 1992; accepted July 7, 1992.
© 1992 by Elsevier Science Publishing Co., Inc.
with preceding autonomic symptoms such as palpitation and sweating, once or twice a year. In March 1990, she was referred to our department. Magnetic resonance imaging (MRI) showed an oval mass lesion located from the medial side o f the right temporal lobe to suprasellar cistern. The mass lesion was o f mixed intensity, without enhancement effect with gadolinium in T 1-weighted image. Spotty high signal intensity areas were found in third and lateral ventricles and in cerebral sulci on the medial cerebral surface (Figure 1). Carotid angiogram showed that the mass was avascular and caused shifting of right C 1 and M 1 medially and superiorly, respectively, along with narrowing of these trunks. N o aneurysm was evident on conventional view (Figure 2 A). She was prescribed carbamazepine in spite of having no abnormality on electroencephalogram. One year later, on admission to the hospital, a neurological examination revealed no abnormality. Preoperative diagnosis was ruptured dermoid cyst. On March 19, 1991, the patient underwent surgery. Right frontotemporal craniotomy revealed floating lipid droplets in the subarachnoid space. A yellowish creamy tumor was discovered in the right suprasellar region from the medial side of the right temporal lobe to the mediobasal part o f the right frontal lobe. The tumor capsule was thin in some parts and thick in others. The thickest part o f the capsule contained hair and was strongly adherent to C1 and M1. When the tumor capsule was finely dissected, a small broad neck aneurysm on proximal M1 trunk and stenosis of the enwrapped C 1 and M 1 were visible. Because a perforator was found at the fundus o f the aneurysm, muscle wrapping of the aneurysm was performed. T h e postoperative course was uneventful. Histological findings were typical of dermoid tumors (Figure 3). Angiogram on 10th postoperative day revealed the secured aneurysm at the right M1 in oblique view and persistent narrowing of C1 and M1 (Figure 2 B). She was discharged without any neurological deficit. Four months after surgery, MRI showed complete removal of the tumor but persistence o f lipid droplets (Figure 4). 0090-3019/92/$5.00
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Figure 1. Magnetic resonance imaging: (A) plain and (B) gadolinium-enhanced coronal view of Tl-weighted scan shows an oval mass with mixed intensity, without enhancement effect in the right suprasellar region. (C) Midline sagittal view of T1 -weighted scan shows spotty high-intensity areas of lipid droplets in ventricle and cerebral sulci. (D) Coronal view of T2-weighted scan shows that the mass lesion is of high intensity.
Suprasellar Dermoid with MCA Aneurysm
Figure 1.
Continued
Discussion Patients with ruptured dermoid cyst may present with headache, seizure, meningitis [9], or transient ischemic attack due to vasospasm [3,11]. Meningitis is rare in spontaneous ruptured dermoid cyst. In our case, the attacks of loss of consciousness accompanied with autonomic symptoms, was appropriately considered to be epilepsy due to temporal irritability because administration of carbamazepine abolished these attacks. CT and MRI showed floating lipid droplets in the subarachnoid space and ventricle, which has been reported as a characteristic finding of ruptured dermoid cyst [2,5,7]. Association of epidermoid or dermoid tumor with cerebral aneurysm is rare, and only two cases have previously been reported. Sasaki et al reported o f a right internal carotid-posterior communicating saccular aneurysm ruptured within a right parasellar epidermoid tumor [ 16]. Angiography failed to detect the aneurysm. Surgery disclosed that the fundus of the aneurysm was completely buried within the tumor. Michael and Paul reported an unruptured Acom aneurysm with suprasellar epidermoid tumor [10]. Angiography and enhanced CT could detect the aneurysm. The tumor was completely encasing the aneurysm. T h e similarity in all three
Surg Neurol 1992;38:341-6
343
cases is that the aneurysm was completely wrapped by and strongly adherent to the tumor capsule. The close anatomical relationship between the aneurysm and the epidermoid or dermoid tumor suggests that the formation of the aneurysm may be related to the surrounding tumor, rather than the incidental coexistence of these lesions. On the other hand, there are several features that distinguish the present patient from the previously reported cases. First, our case presented at a comparatively young age for incidence of aneurysm; age at presentation was approximately 50 years in two other cases. Second, the location o f aneurysm in our case is a relatively rare site for aneurysm, whereas in two other cases, aneurysms were located in circle of Willis. Third, the shape o f the aneurysm is broad neck in our case and saccular shape in other two cases. Fourth, the striking feature in our case is that the thick part of the cyst capsule was wrapping part of the circumference of arteries (C1 and M1), where the stenosis was evident during surgery and in angiography.' In a review of the literature and also in the two previously reported cases, there was no report of arterial stenosis associated with epidermoid and dermoid tumors. The pathogenesis of aneurysm in these cases is unknown. Since epidermoid and dermoid tumors are avascular, hemodynamic stress is not responsible for aneurysm formation in these cases. H o r m o n a l effects have been suspected as a factor for aneurysm formation in pituitary adenoma. Intracranial supratentorial epidermoid and dermoid tumors are aberrant tissue included within the cranium during the closure of the rostal neuropore at Carnegie stage 11 [8,12]. These tissues are foreign to cranial structures and generate an inflammatory response in the surrounding tissue. Thus, fibrosis and strong adhesion of the tumor capsule to the neurovascular structures occur. In the literature reporting large series of epidermoid and dermoid tumors, all the authors mention strong adhesion of the tumor capsule to vital neurovascular structures, which in some cases led them to incomplete removal of tumor [1,8,14,15, 18]. We speculate that weakening of the arterial branching during this inflammatory process leads to aneurysm formation. The same inflammatory process may be responsible for stenosis or narrowing of right C 1 and M 1 in our case. Vasospasm and mechanical pressure are other possible but less likely explanations for arterial narrowing in this case, because the postoperative angiography revealed persistence of narrowing. Finally, in the management of patients with intracranial epidermoid and dermoid tumors, we must bear in mind the possibility of associated vascular lesions, as described here.
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Figure 2. (A) Preoperative right carotid angiography anteroposteriorview shows stenosis and shifting of C1 and M1 trunks (black arrows). (B) Postoperativeangiography in right oblique view shows securedaneurysm (black arrows) and persistent stenosis of C1 and M l trunks (white arrows).
Surg Neurol 1992;38:341-6
345
Figure 3. Stratified squamous epithelium (arrowheads), hair follicle (arrow), and sebaceous gland (sg) in dermoid cyst capsule. (Hematoxylin and eosin stain, original magnification x 50).
Figure 4. Postoperative magnetic resonance imaging: coronal view of (A) Tl-weighted scan plain and (B) T2°weighted scan shows complete removal of tumor but persistence of spotty high-intensity areas of lipid droplets in ventricle and cerebralsulci.
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Surg N e u r o l 1992;38:341-6
References 1. Altshculer EM,Jungreis CA, Sekhar LN,Jannetta pJ, Sheptak PE. Operative treatment of intracranial epidermoid cysts and cholesterol granulomas: report of 21 cases. Neurosurgery 1990;26: 606-14. 2. Davidson HD, Ouchi T, Steiner RE. NMR imaging of congenital intracranial germinal layer neoplasms. Neuroradiology 1985;27: 301-3. 3. Ford K, Drayer B, Osborne D, Dubois P. Case report. Transient cerebral ischemia as a manifestation of ruptured intracranial dermoid cyst. J Comput Assist Tomogr 1981;5:895-7. 4. Fox JL. Intracranial aneurysms. New York. Springer-Verlag, 1983;402-5, 1401-9. 5. Hahn FJ, Ong E, McComb RD, Mawk JR, Leibrock LG. MR imaging of ruptured intracranial dermoid. J Comput Assist Tomogr 1986;10:888-9. 6. Jakubowski J, Kendall B. Coincidental aneurysms with tumors of pituitary origin. J Neurol Neurosurg Psychiatry 1978;41:972-9. 7. Laster DW, Moody DM, Ball MR. Epidermoid tumors with intraventricular and subarachnoid fat: report of 2 cases with CT. Am J Roentgenol 1977;128:504-7. 8. Lunardi P, Missori P. Supratentorial dermoid cysts. J Neurosurg 1991;75:262-6. 9. Lunardi P, Missori P, Rizzo A, Gadliardi FM. Chemical meningitis in ruptured intracranial dermoid. Case report and review of the literature. Surg Neurol 1989;32:449-52.
A h m a d et al
10. Michael LG, Paul BN. Association of an epidermoid tumor with an aneurysm of the anterior communicating artery. Neurosurgery 1988;23:392-5. 11. Mikhael MA. Transient spasm of carotid siphon complicating ruptured cranial dermoid cyst. Radiology 1982;144:824. 12. O'Rahilly R, Muller F. The developmental anatomy and histology of the human central nervous system. In: Vinken PJ, Bruyn GW, Klawans HL, eds. Handbook of clinical neurology, vo150, Malformations. Amsterdam: Elsevier, 1987:1-17. 13. Pia HW, Obrador S, Martin JS. Association of brain tumors and arterial intracranial aneurysms. Acta Neurochir (Wien) 1972;27: 189-204. 14. Rubin G, Scienza R, Pasqualin A, Pian RD. Craniocerebral epidermoids and dermoids. A review of 44 cases. Acta Neurochir (Wien) 1989;97:1-16. 15. Sabin HI, Bordi LT, Symon L. Epidermoid cysts and cholesterol granulomas centered on the posterior fossa: twenty years of diagnosis and management. Neurosurgery 1987;21:798-805. 16. Sasaki S, Matsuo Y, Kuwabara H, Matsuoka K. Rupture of an aneurysm into a parasellar epidermoid cyst. J Neurosurg 1981; 55:629-32~ 17. Wakai S, Fukushima T, Furihata T, Sano K. Association of cerebral aneurysm with pituitary adenoma. Surg Neurol 1979;12:503-7. 18. Yasargil MG, Abernathey CD, Sarioglu AC. Microsurgical treatment of intracranial dermoid and epidermoid tumors. Neurosurgery 1989;24:561-7.
341
Ruptured Suprasellar Dermoid Associated with Middle Cerebral Artery Aneurysm: Case Report Ishtiaq Ahmad, M.B.B.S., Teiji Tominaga, M.D., Akira Ogawa, M.D., and Takashi Yoshimoto, M.D. Division of Neurosurgery, Institute of Brain Diseases, Tohoku University School of Medicine, Sendai, Japan
Ahmad I, Tominaga T, Ogawa A, Yoshimoto T. Ruptured suprasellar dermoid associated with middle cerebral artery aneurysm: case report. Surg Neurol 1992;38:341-6.
Dermoid tumor associated with cerebral aneurysm is extremely rare. We report here a case of ruptured suprasellar dermoid cyst associated with middle cerebral artery (M1) aneurysm and stenosis of adjacent arterial trunks. The characteristic feature of this association is the tight adhesion of the vascular lesion to the tumor capsule. KEY WORDS: Dermoid; Epidermoid; MCA aneurysm; Magnetic resonance imaging
Epidermoid or dermoid tumor with cerebral aneurysm is a rare association. In reviewing the literature, over 140 cases of brain tumor associated with cerebral aneurysm have been reported [4,6,10,13,16,17 ]. However, in only two cases were epidermoid tumors associated with aneurysm [10,16]. Association o f dermoid with cerebral aneurysm has not been described previously. H e r e we report a case o f suprasellar dermoid associated with middle cerebral artery (MCA) aneurysm and stenosis o f adjacent arterial trunks. Based on the operative findings, the pathogenesis of this rare association is briefly discussed.
Case Report A 21-year-old woman was referred to a local hospital with the complaint of headache and nausea in June 1985. A computed tomographic (CT) scan revealed a low-density area in the right middle cranial fossa, and she was diagnosed as having an arachnoid cyst. Beginning in 1986, she complained of attacks o f loss o f consciousness,
Address reprint requests to: I. Ahmad, M.B.B.S., Division of Neurosurgery, Institute of Brain Diseases, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980, Japan. Received June 15, 1992; accepted July 7, 1992.
© 1992 by Elsevier Science Publishing Co., Inc.
with preceding autonomic symptoms such as palpitation and sweating, once or twice a year. In March 1990, she was referred to our department. Magnetic resonance imaging (MRI) showed an oval mass lesion located from the medial side o f the right temporal lobe to suprasellar cistern. The mass lesion was o f mixed intensity, without enhancement effect with gadolinium in T 1-weighted image. Spotty high signal intensity areas were found in third and lateral ventricles and in cerebral sulci on the medial cerebral surface (Figure 1). Carotid angiogram showed that the mass was avascular and caused shifting of right C 1 and M 1 medially and superiorly, respectively, along with narrowing of these trunks. N o aneurysm was evident on conventional view (Figure 2 A). She was prescribed carbamazepine in spite of having no abnormality on electroencephalogram. One year later, on admission to the hospital, a neurological examination revealed no abnormality. Preoperative diagnosis was ruptured dermoid cyst. On March 19, 1991, the patient underwent surgery. Right frontotemporal craniotomy revealed floating lipid droplets in the subarachnoid space. A yellowish creamy tumor was discovered in the right suprasellar region from the medial side of the right temporal lobe to the mediobasal part o f the right frontal lobe. The tumor capsule was thin in some parts and thick in others. The thickest part o f the capsule contained hair and was strongly adherent to C1 and M1. When the tumor capsule was finely dissected, a small broad neck aneurysm on proximal M1 trunk and stenosis of the enwrapped C 1 and M 1 were visible. Because a perforator was found at the fundus o f the aneurysm, muscle wrapping of the aneurysm was performed. T h e postoperative course was uneventful. Histological findings were typical of dermoid tumors (Figure 3). Angiogram on 10th postoperative day revealed the secured aneurysm at the right M1 in oblique view and persistent narrowing of C1 and M1 (Figure 2 B). She was discharged without any neurological deficit. Four months after surgery, MRI showed complete removal of the tumor but persistence o f lipid droplets (Figure 4). 0090-3019/92/$5.00
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Surg Neurol 1992;38:341-6
Figure 1. Magnetic resonance imaging: (A) plain and (B) gadolinium-enhanced coronal view of Tl-weighted scan shows an oval mass with mixed intensity, without enhancement effect in the right suprasellar region. (C) Midline sagittal view of T1 -weighted scan shows spotty high-intensity areas of lipid droplets in ventricle and cerebral sulci. (D) Coronal view of T2-weighted scan shows that the mass lesion is of high intensity.
Suprasellar Dermoid with MCA Aneurysm
Figure 1.
Continued
Discussion Patients with ruptured dermoid cyst may present with headache, seizure, meningitis [9], or transient ischemic attack due to vasospasm [3,11]. Meningitis is rare in spontaneous ruptured dermoid cyst. In our case, the attacks of loss of consciousness accompanied with autonomic symptoms, was appropriately considered to be epilepsy due to temporal irritability because administration of carbamazepine abolished these attacks. CT and MRI showed floating lipid droplets in the subarachnoid space and ventricle, which has been reported as a characteristic finding of ruptured dermoid cyst [2,5,7]. Association of epidermoid or dermoid tumor with cerebral aneurysm is rare, and only two cases have previously been reported. Sasaki et al reported o f a right internal carotid-posterior communicating saccular aneurysm ruptured within a right parasellar epidermoid tumor [ 16]. Angiography failed to detect the aneurysm. Surgery disclosed that the fundus of the aneurysm was completely buried within the tumor. Michael and Paul reported an unruptured Acom aneurysm with suprasellar epidermoid tumor [10]. Angiography and enhanced CT could detect the aneurysm. The tumor was completely encasing the aneurysm. T h e similarity in all three
Surg Neurol 1992;38:341-6
343
cases is that the aneurysm was completely wrapped by and strongly adherent to the tumor capsule. The close anatomical relationship between the aneurysm and the epidermoid or dermoid tumor suggests that the formation of the aneurysm may be related to the surrounding tumor, rather than the incidental coexistence of these lesions. On the other hand, there are several features that distinguish the present patient from the previously reported cases. First, our case presented at a comparatively young age for incidence of aneurysm; age at presentation was approximately 50 years in two other cases. Second, the location o f aneurysm in our case is a relatively rare site for aneurysm, whereas in two other cases, aneurysms were located in circle of Willis. Third, the shape o f the aneurysm is broad neck in our case and saccular shape in other two cases. Fourth, the striking feature in our case is that the thick part of the cyst capsule was wrapping part of the circumference of arteries (C1 and M1), where the stenosis was evident during surgery and in angiography.' In a review of the literature and also in the two previously reported cases, there was no report of arterial stenosis associated with epidermoid and dermoid tumors. The pathogenesis of aneurysm in these cases is unknown. Since epidermoid and dermoid tumors are avascular, hemodynamic stress is not responsible for aneurysm formation in these cases. H o r m o n a l effects have been suspected as a factor for aneurysm formation in pituitary adenoma. Intracranial supratentorial epidermoid and dermoid tumors are aberrant tissue included within the cranium during the closure of the rostal neuropore at Carnegie stage 11 [8,12]. These tissues are foreign to cranial structures and generate an inflammatory response in the surrounding tissue. Thus, fibrosis and strong adhesion of the tumor capsule to the neurovascular structures occur. In the literature reporting large series of epidermoid and dermoid tumors, all the authors mention strong adhesion of the tumor capsule to vital neurovascular structures, which in some cases led them to incomplete removal of tumor [1,8,14,15, 18]. We speculate that weakening of the arterial branching during this inflammatory process leads to aneurysm formation. The same inflammatory process may be responsible for stenosis or narrowing of right C 1 and M 1 in our case. Vasospasm and mechanical pressure are other possible but less likely explanations for arterial narrowing in this case, because the postoperative angiography revealed persistence of narrowing. Finally, in the management of patients with intracranial epidermoid and dermoid tumors, we must bear in mind the possibility of associated vascular lesions, as described here.
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Surg Neurol 1992;38:341-6
Figure 2. (A) Preoperative right carotid angiography anteroposteriorview shows stenosis and shifting of C1 and M1 trunks (black arrows). (B) Postoperativeangiography in right oblique view shows securedaneurysm (black arrows) and persistent stenosis of C1 and M l trunks (white arrows).
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345
Figure 3. Stratified squamous epithelium (arrowheads), hair follicle (arrow), and sebaceous gland (sg) in dermoid cyst capsule. (Hematoxylin and eosin stain, original magnification x 50).
Figure 4. Postoperative magnetic resonance imaging: coronal view of (A) Tl-weighted scan plain and (B) T2°weighted scan shows complete removal of tumor but persistence of spotty high-intensity areas of lipid droplets in ventricle and cerebralsulci.
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Surg N e u r o l 1992;38:341-6
References 1. Altshculer EM,Jungreis CA, Sekhar LN,Jannetta pJ, Sheptak PE. Operative treatment of intracranial epidermoid cysts and cholesterol granulomas: report of 21 cases. Neurosurgery 1990;26: 606-14. 2. Davidson HD, Ouchi T, Steiner RE. NMR imaging of congenital intracranial germinal layer neoplasms. Neuroradiology 1985;27: 301-3. 3. Ford K, Drayer B, Osborne D, Dubois P. Case report. Transient cerebral ischemia as a manifestation of ruptured intracranial dermoid cyst. J Comput Assist Tomogr 1981;5:895-7. 4. Fox JL. Intracranial aneurysms. New York. Springer-Verlag, 1983;402-5, 1401-9. 5. Hahn FJ, Ong E, McComb RD, Mawk JR, Leibrock LG. MR imaging of ruptured intracranial dermoid. J Comput Assist Tomogr 1986;10:888-9. 6. Jakubowski J, Kendall B. Coincidental aneurysms with tumors of pituitary origin. J Neurol Neurosurg Psychiatry 1978;41:972-9. 7. Laster DW, Moody DM, Ball MR. Epidermoid tumors with intraventricular and subarachnoid fat: report of 2 cases with CT. Am J Roentgenol 1977;128:504-7. 8. Lunardi P, Missori P. Supratentorial dermoid cysts. J Neurosurg 1991;75:262-6. 9. Lunardi P, Missori P, Rizzo A, Gadliardi FM. Chemical meningitis in ruptured intracranial dermoid. Case report and review of the literature. Surg Neurol 1989;32:449-52.
A h m a d et al
10. Michael LG, Paul BN. Association of an epidermoid tumor with an aneurysm of the anterior communicating artery. Neurosurgery 1988;23:392-5. 11. Mikhael MA. Transient spasm of carotid siphon complicating ruptured cranial dermoid cyst. Radiology 1982;144:824. 12. O'Rahilly R, Muller F. The developmental anatomy and histology of the human central nervous system. In: Vinken PJ, Bruyn GW, Klawans HL, eds. Handbook of clinical neurology, vo150, Malformations. Amsterdam: Elsevier, 1987:1-17. 13. Pia HW, Obrador S, Martin JS. Association of brain tumors and arterial intracranial aneurysms. Acta Neurochir (Wien) 1972;27: 189-204. 14. Rubin G, Scienza R, Pasqualin A, Pian RD. Craniocerebral epidermoids and dermoids. A review of 44 cases. Acta Neurochir (Wien) 1989;97:1-16. 15. Sabin HI, Bordi LT, Symon L. Epidermoid cysts and cholesterol granulomas centered on the posterior fossa: twenty years of diagnosis and management. Neurosurgery 1987;21:798-805. 16. Sasaki S, Matsuo Y, Kuwabara H, Matsuoka K. Rupture of an aneurysm into a parasellar epidermoid cyst. J Neurosurg 1981; 55:629-32~ 17. Wakai S, Fukushima T, Furihata T, Sano K. Association of cerebral aneurysm with pituitary adenoma. Surg Neurol 1979;12:503-7. 18. Yasargil MG, Abernathey CD, Sarioglu AC. Microsurgical treatment of intracranial dermoid and epidermoid tumors. Neurosurgery 1989;24:561-7.
