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Ruptured aneurysm associated with arachnoid cyst: Intracystic hematoma without subarachnoid hemorrhage
ELSEVIER
Vascular
RUPTURED ANEURYSM ASSOCIATED WITH ARACHNOID CYST: INTRACYSTIC HEMATOMA WITHOUT SUBARACHNOID HEMORRHAGE Satoshi Hirose, M.D., Sadahiro Shimada, M.D., Narihito Yamaguchi, M.D., Kazuo Hosotani, M.D., Hirokazu Kawano, M.D., and Toshihiko Kubota, M.D. Department of Neurosurgery, Harue Hospital; Department of Neurosurgery, Kanazawa University School of Medicine; and Department of Neurosurgery, Fukui Medical School, Fukui, Japan
Hirose S, Shimada S, Yamaguchi N, Hosotani K, Kawano H, Kubota T. Ruptured aneurysm associated with arachnoid cyst: intracystic hematoma without subarachnoid hemorrhage. Surg Neurol 1995;43:353-6. BACKGROUND
It is well-known that arachnoid cysts of the middle fossa are associated often with chronic subdural hematomas and/or intracystic hemorrhages. However, reports of an arachnoid cyst associated with an aneurysm are rare. CASE
tic hemorrhages
[ 1,3,4,6,12]. However,
reports of an arachnoid cyst associated with an aneurysm are rare [5]. There have been no previous report of an intracystic hematoma due to a ruptured aneurysm. We present a patient with an arachnoid cyst who suffered only an intracystic hemorrhage after rupture of a saccular aneurysm.
DESCRIPTION
A 45-year-old man was admitted with headache due to intracystic hemorrhage in the sylvian fissure, associated with a saccular aneurysm at the bifurcation of the internal carotid artery. The aneurysm ruptured into the arachnoid cyst, without causing a subarachnoid hemorrhage. Subsequently, the neck of the aneurysm was clipped successfully. The patient’s postoperative course was uneventful, and there was no vasospasm. CONCLUSIONS
This is the first reported case of an due to a ruptured aneurysm. We etiology of the association between arachnoid cyst, and the formation intracystic hematoma that did not
intracystic hematoma discuss the possible the aneurysm and the mechanism for the result in a subarach-
noid hemorrhage. KEY WORDS
Arachnoid cyst, intracystic hematoma,
ruptured aneurysm.
T
he recent detection of arachnoid cysts has increased due to the widespread use of computed tomography (CT). It is well-known that arachnoid cysts of the middle fossa are associated often with chronic subdural hematomas and/or intracysAddress rosurgery, gun, Fukui, Received
reprint requests to: Satoshi Hirose, M.D., Department of NeuHarue Hospital, 62-5 Edomeshimo Yashiki, Harue-cho, SakaiJapan. September 2, 1994; accepted September 26. 1994.
0 1995 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY
10010
CASEREPORT A 45-year-old man was admitted to Harue Hospital on September 29, 1993, due to the sudden onset of a headache without signs of meningeal irritation. He had no history of seizures, trauma, mental disorder, or physical disability. There was no head asymmetry or papilledema on examination, although there was a slight right-hand weakness. The remainder of the neurologic examination was unremarkable. Skull radiographs showed an enlarged left middle fossa and elevation of the lesser wing of the sphenoid. The initial computed tomography (CT) scan performed on admission demonstrated a large lowdensity area in the left middle fossa that included a dense, solid mass (Figure 1). An arachnoid cyst with an intracystic hemorrhage was diagnosed. Magnetic resonance imaging (MRI) revealed a high-intensity solid mass, contained to the cyst with no pericystic lesions on hospital day 2. On the third hospital day, a left angiogram revealed an elevated middle cerebral artery and a saccular aneurysm at the bifurcation of the internal carotid artery. The dome of the aneurysm projected posteriorly on the lateral angiogram (Figure 2). Craniosurgery was planned, however the patient experienced a severe 0090-3019/95/$9.50 SSDl 0090-3019(94)00344-P
354
Surg Neurol 1995;43:353-6
Hirose et al
initial computed tomography scan obtained after the first hemorrhage, q The the left middle fossa with including a dense solid mass (arrowheads).
headache accompanied by motor aphasia and right hemiparesis on the fourth hospital day. A CT scan at that time showed additional bleeding into the arachnoid cyst (Figure 3). The patient was diagnosed with an intracystic hemorrhage secondary to a ruptured aneurysm. Emergency surgery was performed via a frontotemporal craniotomy. The wall of the cyst was bulging when the dura mater was incised. The cyst contained bloody fluid and a solid hematoma. The and caarachnoid membrane of the prechiasmatic
Frontal view of left carotid angiogram q at(Left): the bifurcation of the internal carotid aneurysm
which projects
posteriorly
showing a large lowdensity
area in
rotid cistern was opened using a frontobasal approach. There was no subarachnoid hemorrhage. The intracystic hematoma was evacuated by irrigation after the left internal carotid artery was identified. The aneurysm at the bifurcation of the left internal carotid artery was surrounded by the wall of the arachnoid cyst. However, the top of the aneurysmal dome perforated the cyst (Figure 4). The neck of the aneurysm was clipped. An empty middle cranial fossa also was observed. The left temporal lobe was severely atrophic, and the frontal opercu-
showing an elevated middle cerebral artery and a saccular aneurysm artery. (Right): Lateral view of left carotid angiogram showing an (arrow and inset).
Ruptured
Aneurysm
Forms Hematoma
in Arachnoid
Surg Neurol 1995;43:353-6
Cyst
was discharged from without any discernible
the hospital neurologic
3 weeks deficits.
355
later
DISCUSSION Arachnoid cysts in the middle cranial fossa initially were identified in 1831. Arachnoid cysts are not neoplasms, but are estimated to comprise approximately 1% of all intracranial, space-occupying lesions. More detailed information about arachnoid cysts is available because of CT findings that dem-
Computed tomography scan obtained on the fourth hospital day showing additional bleeding into the arachnoid cyst without subarachnoid hemorrhage.
Q
lar cortex appeared mildly atrophic. The patient’s recovery was uneventful. An angiogram performed on postoperative day 6 revealed complete and intact clipping, and no evidence of vasospasms. He
Illustration of the pterional approach. The arach1 q noid membrane of the prechiasmatic and carotid cistern was incised. The wall of the arachnoid cyst was opened (arrowheads), and the intracystic hematoma was evacuated. There was no evidence of a subarachnoid hemorrhage. The aneurysm at the bifurcation of the left internal carotid artery was surrounded by the wall of the arachnoid cyst. However, the top of the aneurysmal dome
perforated the cyst (asterisk). Abbreviations: II, optic nerve; ICA, internal carotid artery; ACA, anterior cerebral artery; MCA, middle cerebral artery; A.C., arachnoid cyst.
onstrate homogenous water-dense masses with sharp margins. Arachnoid cysts lack calcification and fat, hence, they do not demonstrate contrast enhancement. The radiographic features of arachnoid cysts are well-known. Skull radiographs reveal bulging of the cranial vault, and conventional angiography displays avascular, extra-axial masses KNf21. However, most reports have cited calculated incidences of intracranial aneurysms from general autopsy series as high as 2%-5% [ 1 I]. McCormick and Acosta-Rua have found aneurysms in 8% of the cases in an autopsy study. Twenty-eight percent of these lesions were thought to be ruptured [7,8]. However, reports of an arachnoid cyst associated with a subarachnoid hemorrhage are rare [5]. Reports of arachnoid cysts with associated chronic subdural hematomas have increased in recent years [ 1,9]. Initially, we suspected that our patient had an intracystic hematoma associated with a subdural hematoma of the middle cranial fossa. However, MRI did not demonstrate a subdural hematoma in the middle cranial fossa. Subsequent cerebral angiography indicated the diagnosis of a ruptured aneurysm. Usually, ruptured intracranial aneurysms initially hemorrhage into the subarachnoid space. With recurrent hemorrhagic episodes, dissection into the cerebral parenchyma and/or bleeding into the subdural (epiarachnoid) space may occur [2]. However, no such episodes of intracranial hemorrhaging occurred in our patient. Arachnoid cysts of the middle cranial fossa may deform the surrounding bone by erosion or expansion. The sphenoid ridge is elevated and the greater wing is remodeled and projected forward. Erosion may involve the temporal, frontal, and/or parietal bones. Starkman has studied autopsied specimens systematically and concluded that arachnoid cysts are formed by the splitting or duplication of the arachnoid membrane [12]. This hypothesis is supported additionally by light and electron microscopic studies of the walls of cysts. Peripheral portions of the cavity were
356
Surg Neurol 1995;43:353-6
lined with arachnoid tissue. As this tissue approaches the brain, it fuses with the normal arachnoid over the adjacent gyri [10,13]. Therefore, we hypothesize in our case that the pulsation, the expansiveness, and the easy adhesion to the sur-
rounding tissue of arachnoid cyst’s walls, associated with pulsation in the aneurysmal wall, contributed to intracystic bleeding. Vasospasm did not occur in our patient because the aneurysm repeatedly ruptured into the cyst without causing a subarachnoid hemorrhage. Our patient made a full recovery. To our knowledge, this is the first reported case of an intracystic hematoma secondary to a ruptured cerebral aneurysm in the absence of a subarachnoid hemorrhage.
Hirose et al
5.
6.
7.
8.
9.
REFERENCES Auer LM, Gallhofer B, Ladurner G, Sager WD, Heppner F, Lechner H. Diagnosis and treatment of middle fossa arachnoid cysts and subdural hematomas. J Neurosurg 1981;54:366-9. Clarke E, Walton JN. Subdural hematoma complicating intracranial aneurysm and angioma. Brain 1953; 76~378-404. Giudicelli G, Hassoun J, Choux M, Tonon C. Les kystes (arachnoidiens) supratentoriels. J Neuroradiology 1982;9:179-201. Hara H, moue T, Matsuo K, Kobayashi S, Sugita K.
10.
11.
12. 13.
Unusual computed tomographic findings in a case of arachnoid cyst in the middle fossa. Surg Neurol 1984; 22:79-82. Jinkins JR, Siqueira EB, Holoubi A. Ruptured middle cerebral aneurysm with accumulation of subarachnoid blood within convexity arachnoid cyst. Computerized Radio1 1987;11:185-7. Leo JS, Pinto RS, Hulvat GF, Epstein F, Kricheff II. Computed tomography of arachnoid cysts. Radiology 1979;130:675-80. McCormick WF. The natural history of intracranial saccular aneurysms. Weekly Update Neurol Neurosurg 1978;3:1-8. McCormick WF, Acosta-Rua GJ. The size of intracranial saccular aneurysms. An autopsy study. J Neurosurg 1970;33:422-7. Page A, Paxton RM, Mohan D. A reappraisal of the relationship between arachnoid cysts of the middle fossa and chronic subdural haematoma. J Neurol Neurosurg Psychiatry 1987;50:1001-7. Schumacher M, Baust W, Terwey B. Unusual combination of cerebral dysplasias. Neurochirurgia 1986; 29:210-4. Sekhar LN, Heros RC. Origin, growth, and rupture of saccular aneurysms: a review. Neurosurgery 1981;8: 248-60. Starlunan SP, Brown TC, Line11 EA. Cerebral arachnoid cysts. J Neuropath Exp Neurol 1958;17:484-500. Wild K, Gullotta F. Arachnoid cyst of the middle cranial fossa-aplasia of temporal lobe? Child’s Nerv Syst 1987;3:232-4.
E
VERYWHERE 1 HAVE SOUGHT REST AND NOT FOUND IT, EXCEPT SITTING IN A CORNER BY MYSELF WITH A LITTLE BOOK. -THOMAS
A KEMPIS (1380-l 471) GERMAN MONK, MYSTIC
Vascular
RUPTURED ANEURYSM ASSOCIATED WITH ARACHNOID CYST: INTRACYSTIC HEMATOMA WITHOUT SUBARACHNOID HEMORRHAGE Satoshi Hirose, M.D., Sadahiro Shimada, M.D., Narihito Yamaguchi, M.D., Kazuo Hosotani, M.D., Hirokazu Kawano, M.D., and Toshihiko Kubota, M.D. Department of Neurosurgery, Harue Hospital; Department of Neurosurgery, Kanazawa University School of Medicine; and Department of Neurosurgery, Fukui Medical School, Fukui, Japan
Hirose S, Shimada S, Yamaguchi N, Hosotani K, Kawano H, Kubota T. Ruptured aneurysm associated with arachnoid cyst: intracystic hematoma without subarachnoid hemorrhage. Surg Neurol 1995;43:353-6. BACKGROUND
It is well-known that arachnoid cysts of the middle fossa are associated often with chronic subdural hematomas and/or intracystic hemorrhages. However, reports of an arachnoid cyst associated with an aneurysm are rare. CASE
tic hemorrhages
[ 1,3,4,6,12]. However,
reports of an arachnoid cyst associated with an aneurysm are rare [5]. There have been no previous report of an intracystic hematoma due to a ruptured aneurysm. We present a patient with an arachnoid cyst who suffered only an intracystic hemorrhage after rupture of a saccular aneurysm.
DESCRIPTION
A 45-year-old man was admitted with headache due to intracystic hemorrhage in the sylvian fissure, associated with a saccular aneurysm at the bifurcation of the internal carotid artery. The aneurysm ruptured into the arachnoid cyst, without causing a subarachnoid hemorrhage. Subsequently, the neck of the aneurysm was clipped successfully. The patient’s postoperative course was uneventful, and there was no vasospasm. CONCLUSIONS
This is the first reported case of an due to a ruptured aneurysm. We etiology of the association between arachnoid cyst, and the formation intracystic hematoma that did not
intracystic hematoma discuss the possible the aneurysm and the mechanism for the result in a subarach-
noid hemorrhage. KEY WORDS
Arachnoid cyst, intracystic hematoma,
ruptured aneurysm.
T
he recent detection of arachnoid cysts has increased due to the widespread use of computed tomography (CT). It is well-known that arachnoid cysts of the middle fossa are associated often with chronic subdural hematomas and/or intracysAddress rosurgery, gun, Fukui, Received
reprint requests to: Satoshi Hirose, M.D., Department of NeuHarue Hospital, 62-5 Edomeshimo Yashiki, Harue-cho, SakaiJapan. September 2, 1994; accepted September 26. 1994.
0 1995 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY
10010
CASEREPORT A 45-year-old man was admitted to Harue Hospital on September 29, 1993, due to the sudden onset of a headache without signs of meningeal irritation. He had no history of seizures, trauma, mental disorder, or physical disability. There was no head asymmetry or papilledema on examination, although there was a slight right-hand weakness. The remainder of the neurologic examination was unremarkable. Skull radiographs showed an enlarged left middle fossa and elevation of the lesser wing of the sphenoid. The initial computed tomography (CT) scan performed on admission demonstrated a large lowdensity area in the left middle fossa that included a dense, solid mass (Figure 1). An arachnoid cyst with an intracystic hemorrhage was diagnosed. Magnetic resonance imaging (MRI) revealed a high-intensity solid mass, contained to the cyst with no pericystic lesions on hospital day 2. On the third hospital day, a left angiogram revealed an elevated middle cerebral artery and a saccular aneurysm at the bifurcation of the internal carotid artery. The dome of the aneurysm projected posteriorly on the lateral angiogram (Figure 2). Craniosurgery was planned, however the patient experienced a severe 0090-3019/95/$9.50 SSDl 0090-3019(94)00344-P
354
Surg Neurol 1995;43:353-6
Hirose et al
initial computed tomography scan obtained after the first hemorrhage, q The the left middle fossa with including a dense solid mass (arrowheads).
headache accompanied by motor aphasia and right hemiparesis on the fourth hospital day. A CT scan at that time showed additional bleeding into the arachnoid cyst (Figure 3). The patient was diagnosed with an intracystic hemorrhage secondary to a ruptured aneurysm. Emergency surgery was performed via a frontotemporal craniotomy. The wall of the cyst was bulging when the dura mater was incised. The cyst contained bloody fluid and a solid hematoma. The and caarachnoid membrane of the prechiasmatic
Frontal view of left carotid angiogram q at(Left): the bifurcation of the internal carotid aneurysm
which projects
posteriorly
showing a large lowdensity
area in
rotid cistern was opened using a frontobasal approach. There was no subarachnoid hemorrhage. The intracystic hematoma was evacuated by irrigation after the left internal carotid artery was identified. The aneurysm at the bifurcation of the left internal carotid artery was surrounded by the wall of the arachnoid cyst. However, the top of the aneurysmal dome perforated the cyst (Figure 4). The neck of the aneurysm was clipped. An empty middle cranial fossa also was observed. The left temporal lobe was severely atrophic, and the frontal opercu-
showing an elevated middle cerebral artery and a saccular aneurysm artery. (Right): Lateral view of left carotid angiogram showing an (arrow and inset).
Ruptured
Aneurysm
Forms Hematoma
in Arachnoid
Surg Neurol 1995;43:353-6
Cyst
was discharged from without any discernible
the hospital neurologic
3 weeks deficits.
355
later
DISCUSSION Arachnoid cysts in the middle cranial fossa initially were identified in 1831. Arachnoid cysts are not neoplasms, but are estimated to comprise approximately 1% of all intracranial, space-occupying lesions. More detailed information about arachnoid cysts is available because of CT findings that dem-
Computed tomography scan obtained on the fourth hospital day showing additional bleeding into the arachnoid cyst without subarachnoid hemorrhage.
Q
lar cortex appeared mildly atrophic. The patient’s recovery was uneventful. An angiogram performed on postoperative day 6 revealed complete and intact clipping, and no evidence of vasospasms. He
Illustration of the pterional approach. The arach1 q noid membrane of the prechiasmatic and carotid cistern was incised. The wall of the arachnoid cyst was opened (arrowheads), and the intracystic hematoma was evacuated. There was no evidence of a subarachnoid hemorrhage. The aneurysm at the bifurcation of the left internal carotid artery was surrounded by the wall of the arachnoid cyst. However, the top of the aneurysmal dome
perforated the cyst (asterisk). Abbreviations: II, optic nerve; ICA, internal carotid artery; ACA, anterior cerebral artery; MCA, middle cerebral artery; A.C., arachnoid cyst.
onstrate homogenous water-dense masses with sharp margins. Arachnoid cysts lack calcification and fat, hence, they do not demonstrate contrast enhancement. The radiographic features of arachnoid cysts are well-known. Skull radiographs reveal bulging of the cranial vault, and conventional angiography displays avascular, extra-axial masses KNf21. However, most reports have cited calculated incidences of intracranial aneurysms from general autopsy series as high as 2%-5% [ 1 I]. McCormick and Acosta-Rua have found aneurysms in 8% of the cases in an autopsy study. Twenty-eight percent of these lesions were thought to be ruptured [7,8]. However, reports of an arachnoid cyst associated with a subarachnoid hemorrhage are rare [5]. Reports of arachnoid cysts with associated chronic subdural hematomas have increased in recent years [ 1,9]. Initially, we suspected that our patient had an intracystic hematoma associated with a subdural hematoma of the middle cranial fossa. However, MRI did not demonstrate a subdural hematoma in the middle cranial fossa. Subsequent cerebral angiography indicated the diagnosis of a ruptured aneurysm. Usually, ruptured intracranial aneurysms initially hemorrhage into the subarachnoid space. With recurrent hemorrhagic episodes, dissection into the cerebral parenchyma and/or bleeding into the subdural (epiarachnoid) space may occur [2]. However, no such episodes of intracranial hemorrhaging occurred in our patient. Arachnoid cysts of the middle cranial fossa may deform the surrounding bone by erosion or expansion. The sphenoid ridge is elevated and the greater wing is remodeled and projected forward. Erosion may involve the temporal, frontal, and/or parietal bones. Starkman has studied autopsied specimens systematically and concluded that arachnoid cysts are formed by the splitting or duplication of the arachnoid membrane [12]. This hypothesis is supported additionally by light and electron microscopic studies of the walls of cysts. Peripheral portions of the cavity were
356
Surg Neurol 1995;43:353-6
lined with arachnoid tissue. As this tissue approaches the brain, it fuses with the normal arachnoid over the adjacent gyri [10,13]. Therefore, we hypothesize in our case that the pulsation, the expansiveness, and the easy adhesion to the sur-
rounding tissue of arachnoid cyst’s walls, associated with pulsation in the aneurysmal wall, contributed to intracystic bleeding. Vasospasm did not occur in our patient because the aneurysm repeatedly ruptured into the cyst without causing a subarachnoid hemorrhage. Our patient made a full recovery. To our knowledge, this is the first reported case of an intracystic hematoma secondary to a ruptured cerebral aneurysm in the absence of a subarachnoid hemorrhage.
Hirose et al
5.
6.
7.
8.
9.
REFERENCES Auer LM, Gallhofer B, Ladurner G, Sager WD, Heppner F, Lechner H. Diagnosis and treatment of middle fossa arachnoid cysts and subdural hematomas. J Neurosurg 1981;54:366-9. Clarke E, Walton JN. Subdural hematoma complicating intracranial aneurysm and angioma. Brain 1953; 76~378-404. Giudicelli G, Hassoun J, Choux M, Tonon C. Les kystes (arachnoidiens) supratentoriels. J Neuroradiology 1982;9:179-201. Hara H, moue T, Matsuo K, Kobayashi S, Sugita K.
10.
11.
12. 13.
Unusual computed tomographic findings in a case of arachnoid cyst in the middle fossa. Surg Neurol 1984; 22:79-82. Jinkins JR, Siqueira EB, Holoubi A. Ruptured middle cerebral aneurysm with accumulation of subarachnoid blood within convexity arachnoid cyst. Computerized Radio1 1987;11:185-7. Leo JS, Pinto RS, Hulvat GF, Epstein F, Kricheff II. Computed tomography of arachnoid cysts. Radiology 1979;130:675-80. McCormick WF. The natural history of intracranial saccular aneurysms. Weekly Update Neurol Neurosurg 1978;3:1-8. McCormick WF, Acosta-Rua GJ. The size of intracranial saccular aneurysms. An autopsy study. J Neurosurg 1970;33:422-7. Page A, Paxton RM, Mohan D. A reappraisal of the relationship between arachnoid cysts of the middle fossa and chronic subdural haematoma. J Neurol Neurosurg Psychiatry 1987;50:1001-7. Schumacher M, Baust W, Terwey B. Unusual combination of cerebral dysplasias. Neurochirurgia 1986; 29:210-4. Sekhar LN, Heros RC. Origin, growth, and rupture of saccular aneurysms: a review. Neurosurgery 1981;8: 248-60. Starlunan SP, Brown TC, Line11 EA. Cerebral arachnoid cysts. J Neuropath Exp Neurol 1958;17:484-500. Wild K, Gullotta F. Arachnoid cyst of the middle cranial fossa-aplasia of temporal lobe? Child’s Nerv Syst 1987;3:232-4.
E
VERYWHERE 1 HAVE SOUGHT REST AND NOT FOUND IT, EXCEPT SITTING IN A CORNER BY MYSELF WITH A LITTLE BOOK. -THOMAS
A KEMPIS (1380-l 471) GERMAN MONK, MYSTIC