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Aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus
Surg Neurol 1984;21:231-5
231
Aneurysm of the Anterior Inferior Cerebellar Artery at the Internal Auditory Meatus Kou Nakagawa, M.D., Saburo Sakaki, M.D., Hideki Kimura, M.D., and Kenzo Matsuoka, M.D. Department of Neurological Surgery, Ehime University Medical School, Ehime, Japan
Nakagawa K, Sakaki S, Kimura H, Matsuoka K. Aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus. Surg Neurol 1984;21:231-5.
An aneurysm of the anterior inferior cerebellar artery extending into the internal auditory meatus is reported. The patient developed headache and vomiting caused by a subarachnoid hemorrhage, and rapidly showed signs and symptoms of a lesion in the cerebellopontine angle soon after the onset. At operation, a clip was successfully applied to the neck of the aneurysm. The characteristic clinical findings are briefly reviewed. KEY WORDS: Intracranial aneurysm; Anterior inferior cerebellar artery; Internal auditory meatus
A m o n g aneurysms of the vertebrobasilar system, an aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus is very rare. Moreover, it is of interest for neurosurgeons to observe that some cases with aneurysm at this particular site develop signs and symptoms of a lesion in the cerebellopontine angle before or after an attack of aneurysmal rupture. We experienced such a case in which the aneurysm was successfully clipped. T h e clinical course and radiologic findings in this case are presented.
Case R e p o r t A 40-year-old w o m a n experienced sudden onset of severe occipital headache, vomiting, and vertigo on January 17, 1981. She went to the emergency hospital on the day of the attack, where a lumbar puncture revealed bloody cerebrospinal fluid. On the next day, a hearing
Address reprint requests to: Dr. Kou Nakagawa, Department of Neurological Surgery, Ehime University Medical School, Shigenobucho, Onsen-Gun, Ehime, 791-02 Japan.
(c3 i984 by Elsevier Science Publishing Co., Inc.
loss on the left side and tinnitus were noted, and the patient was transferred to Ehime University Hospital. On admission, vital signs and general physical condition were not impaired. Blood pressure was 140/80 m m Hg. The patient was alert and well oriented regarding time and place. T h e r e was mild nuchal rigidity. She had a floating sensation on standing or walking, but no abnormalities were noted in the m o t o r and sensory systems. Ocular m o v e m e n t s were normal except for a horizontal nystagmus on right lateral gaze. Pupillary reactions and optic fundi were normal. T h e r e was a severe hearing loss in the left ear. W h e n the brainstem evoked responses were recorded, not all waves were obtained by stimulation from the left side (Figure 1). O t h e r cranial nerves were intact. On lumbar puncture, grossly bloody cerebrospinal fluid was obtained with an opening pressure of 180 m m H 2 0 . C o m p u t e d tomography scanning on January 18, 1981 disclosed blood in the subarachnoid space almost symmetrically. A plain x-ray film of the skull demonstrated no abnormal findings. Vertebral angiography demonstrated a saccular aneurysm of the left anterior inferior cerebellar artery extending into the internal auditory meatus, measuring 5 x 4 m m in diameter, which was most clearly revealed in the Stenver projection (Figure 2). T h e r e were no abnormalities in the angiograms of the carotid artery. The patient was kept at bed rest and treated with glycerol, dexamethasone, and antifibrinolytic drugs. H e r neurological condition was improving until the time of the operation. On January 27, 1981, a left suboccipital craniectomy was p e r f o r m e d with the patient in a sitting position. On opening the dura mater, the arachnoid m e m b r a n e was found to be thickened and slightly adherent to the dura mater. However, subarachnoid hemorrhage was not very conspicuous. After the left cerebellar hemisphere was retracted and the cerebellopontine angle explored, the seventh and eighth cranial nerves were found to be markedly compressed and pushed posteriorly close to the orifice of the internal auditory meatus by the aneu009(I-3019/84/S ~.00
232
Surg Neurol 1984;21:231-5
Nakagawa et al
Figure 1. Audiogram of brainstem evoked response, revealing absence of response on left side.
rysm. As a portion of the meatal loop of the anterior inferior cerebellar artery ran between the seventh and eighth cranial nerves and the aneurysm was adherent to the eighth nerve, it was necessary to sacrifice the latter to expose the aneurysm and the parent artery (Figure 3). A clip was applied successfully to the neck of the aneurysm within 10 minutes after temporary clipping of the anterior inferior cerebellar artery proximally. Postoperatively, the patient had a left facial palsy and tinnitus; the latter disappeared gradually. There was no other neurological deficit. Postoperative angiography confirmed complete obliteration of the aneurysm. The patient was discharged in satisfactory condition 25 days after the operation, and the facial palsy resolved completely 6 months later.
A
Discussion Since 1948, when Schwartz reported the first case o f an aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus [14], only 13 such cases have appeared in the literature (Table 1) [2,3,5-11,13,15,16]. Among these cases were a few in which signs and symptoms of a lesion in the cerebellopontine angle developed gradually without any evidence of aneurysmal rupture. It was difficult to differentiate such aneurysms from tumors. In most other cases, there was sudden onset of severe headache, nausea, and vomiting caused by subarachnoid hemorrhage followed by rapid progression of palsies of the seventh and eighth cranial nerves. Acoustic neurinomas, however, may present with sudden onset of hearing loss. Therefore, an adequate investigation must be undertaken to make the diagnosis of an aneurysm when typical symptoms of aneurysmal rupture do not occur. Several authors have reported audiometric study showing fluctuation or gradual improvement of hearing loss as one useful diagnostic test in cases o f aneurysm [8,11,16]. It is important that the function o f
B Figure 2. Vertebral angiography of right side. frontal view, showing aneurysm of anterior inferior cerebellar artery at internal auditory meatus (A) that is more clearly demonstrated in Stenver projection (B).
the eighth cranial nerve be examined from time to time during the clinical course. In the present case, the patient had no complaints before rupture of the aneurysm, and an impairment of the eighth cranial nerve developed abruptly after the hemorrhage. The brainstem evoked response showed a complete disturbance of the eighth cranial nerve, although the function of the nerve was examined only once.
Aneurysm of the Anterior Inferior Cerebellar Artery
The clinical symptoms after rupture of an aneurysm are closely related to the anatomic relation of the anterior inferior cerebellar artery to the internal auditory meatus. The internal auditory artery originates from the meatal loop of the anterior inferior cerebellar artery in the vicinity of the internal auditory meatus in 5 0 - 9 0 % of cases [4,9]. As the aneurysm is assumed to develop at the junction of the anterior inferior cerebellar artery and the internal auditory artery [12], it consequently expands into the internal auditory meatus. When such an aneurysm ruptures, functional damage of the nearby cranial nerves probably arises from circulatory disturbances through vasospasm or compression by the hematoma. Detailed descriptions of the surgical treatment have been given in 12 reported cases, including the present one. In seven cases, the neck of the aneurysm was clipped; in three, the aneurysm was trapped; in one, the anterior inferior cerebellar artery was obliterated proximal to the aneurysm close to the internal auditory meatus; and in one, the aneurysm was treated by coating. Although
Figure 3. Photograph taken at operation. T__NN = t r i g e m i n a l nerve (fifth cranial nerve?: C H = cerebellar hemisphere," A I C A = anterior inferior cerebellar artery: F__NN= f a c i a l nerve (seventh cranial nero,e): A.N_N = a n e u ~ s m .
Surg Neurol 1984;21:23l-5
233
Atkinson emphasized that clipping of the anterior inferior cerebellar artery is very dangerous, especially in the portion of the meatal loop because of decreasing blood supply to the brainstem [1], the cases in which this artery was interrupted did not always develop dysfunction of the brainstem. In the present case, temporary clipping of the artery was performed with no vital changes appearing during the procedure. Perhaps circulatory disorders of the brainstem did not develop because of the anastomoses existing between the anterior inferior cerebellar artery and the posterior inferior cerebellar artery and the superior cerebellar artery. However, postoperative facial palsy and hearing loss occurred frequently in the cases treated by interruption of the anterior inferior cerebellar artery, whereas no neurological deficits were observed in those treated by clipping the neck of the aneurysm. As it is obscure whether this difference results from the involvement of the vascular system or from direct manipulation of the cranial nerves, meticulous surgical procedures for maintaining the vascular integrity of the arteries should be required to preserve the function o f the seventh and eighth cranial nerves.
234
Surg N e u r o l 1984;21:231-5
N a k a g a w a et al
T a b l e 1. Summary of Cases of Aneurysm of the Anterior Inferior Cerebellar Artery at the Internal Auditory Meatus Reference Year
Author
Age Sex
Side
Presenting signs and symptoms
F
L
Headache, vomiting, left-sided hearing loss and trigeminal palsy, nystagmus, dizziness, left-sided facial palsy, bilateral ataxia; SAH Right-sided hearing loss, tinnitus, trigeminal neuralgia, and facial palsy Headache, vomiting, left-sided facial palsy, bilateral hearing loss, tinnitus, nystagmus; SAH Confusion, headache, left-sided facial palsy, convulsion, dysphagia, diplopia; SAH Right-sided hearing loss
1948
Schwartz [14]
27
1957
Krayengbfihl & Yasargil [10] Castaigne et al
69
1967
Operation
(yr)
R
62
M
L
61
F
R
[3] 1967
Weibel et al [15]
1968 1969
Hitselberger & Gardner [7] Glasscock [5]
49
M
R
1971
Hori et al [8]
35
F
L
1973
Porter & Eyster [13]
20
F
R
1975
Benedetti et al [2]
49
F
R
1978
Johnson & Kline [9] Higuchi et al
54
M
R
53
M
L
1978
R
[6] 1978
Mori et al [11]
48
M
R
1982
Zlomik et al [16]
44
F
L
1983
Present case
40
F
L
Procedure
Complications
Trapping
None
Trapping
Complete deafness on left, facial palsy Death of acute necrosis of liver
Clipping
Clipping
Right-sided hearing loss, Clipping dizziness, inappropriate lacrimation on right Headache, vomiting, left-sided Trapping facial palsy, nystagmus, leftsided hearing loss and tinnitus; SAH Stupor, headache, right-sided hearing loss and facial palsy, vertigo, right-sided hemiparesis; SAH Headache, vomiting, right-sided Clipping ? facial palsy and hearing loss, dizziness, lateropulsion; SAH Confusion, headache, right-sided Obliteration facial palsy and twitching; SAH of AICA Headache, vomiting, left-sided Clipping tinnitus; SAH Right-sided hearing loss, vertigo, Coating nystagmus Left-sided hearing loss, tinnitus, Clipping and trigeminal palsy, nystagmus, vertigo Headache, vomiting, left-sided Clipping hearing loss and tinnitus, nystagmus; SAH
None None
Complete deafness on left
Aggravation of facial palsy and hearing lOSS Right-sided hearing lOSS Right-sided hearing loss and tinnitus None None
None
Abbreviations: yr = year; F = female; L = left; R = right; M = male; AICA = anterior inferior cerebellar artery; SAH = subarachnoid hemorrhage.
References 1. AtkinsonWJ. The anterior inferior cerebellar artery: Its variation, pontine distribution and significance in surgery of cerebellopontine angle tumours. J Neurol Neurosurg Psychiatry 1949; 12:137-51. 2. Benedetti A, Curri D, Carbonin C. Aneurysm of the internal auditory artery revealed by a partial cerebellopontine angle syndrome. Neurochirurgia (Stuttg) 1975;18:126-30.
5. 6. 7. 8.
3. Castaigne P, Pertuiset B, Cambier J, Brunet P. Andvrisme de l'art~re auditive interne rdvdld par une paralysie faciale recidivante. Cure radicale. Presse Med 1967;75:2493-6.
9.
4. Fisch U. The surgical anatomy of the so-called internal auditory artery. In: Hamberger CA, Wersiill J, eds. Disorders of the skull
10.
base region: Proceedings. New York: Wiley-Interscience, 1969:121-30. Glasscock ME. Middle fossa approach to the temporal bone. An otologic frontier. Arch Otolaryngol 1969;90:15-27. Higuchi H, Yajima K, Nakazawa S. A case of aneurysm of the left internal acoustic meatus. No Shinkei Geka 1978;4:401-4. Hitselberger WE, Gardner G Jr. Other tumors of the cerebellopontine angle. Arch Otolaryngol 1968;88:712-4. Hori T, Hirakawa K, Ishijima B, Manaka S, Fukushima T, Shimizu N, Sato T. Aneurysm in the internal auditory meatus. Case report. J Neurosurg 1971;35:605-9. Johnson JH, Kline DG. Anterior inferior cerebellar artery aneurysms. J Neurosurg 1978;48:455-60. Krayenbfihl H, Yasargil MG. Die vaskuli~ren Erkrankungen im
A n e u r y s m o f the A n t e r i o r I n f e r i o r C e r e b e l l a r A r t e r y
Surg N e u r o l 1984;21:231-5
235
Gebiet der Arteria vertebralis und Arteria basialis. Stuttgart: Georg Thieme, 1957.
14. Schwartz HG. Arterial aneurysm of the posterior fossae. J Neurosurg 1948;5:312-6.
11. Mori K, Miyazaki H, Baba M, Kumagami H. Aneurysm in the cerebello-pontine angle and hearing loss. No Shinkei Geka 1978;6:845-53.
15. Weibel J, Fields WS, Campos RJ. Aneurysms of the posterior cervicocranial circulation: Clinical and angiographic considerations. J Neurosurg 1967;26:223-34.
12. Pia HW. Classification ofvertebral-basilar aneurysms. Acta Neurochir IWien) 1979;47:3-30.
16. Zlotnik El, Sklyut AS, Smejanovich AF, Stasenko EN. Saccular aneurysm of the anterior inferior cerebellar internal auditory artery: Case report. J Neurosurg 1982;57:829-32.
13. Porter RJ, Eyster EF. Aneurysms in the anterior inferior cerebellar artery at the internal acoustic meatus: Report of a case. Surg Neurol 1973;1:27-8.
231
Aneurysm of the Anterior Inferior Cerebellar Artery at the Internal Auditory Meatus Kou Nakagawa, M.D., Saburo Sakaki, M.D., Hideki Kimura, M.D., and Kenzo Matsuoka, M.D. Department of Neurological Surgery, Ehime University Medical School, Ehime, Japan
Nakagawa K, Sakaki S, Kimura H, Matsuoka K. Aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus. Surg Neurol 1984;21:231-5.
An aneurysm of the anterior inferior cerebellar artery extending into the internal auditory meatus is reported. The patient developed headache and vomiting caused by a subarachnoid hemorrhage, and rapidly showed signs and symptoms of a lesion in the cerebellopontine angle soon after the onset. At operation, a clip was successfully applied to the neck of the aneurysm. The characteristic clinical findings are briefly reviewed. KEY WORDS: Intracranial aneurysm; Anterior inferior cerebellar artery; Internal auditory meatus
A m o n g aneurysms of the vertebrobasilar system, an aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus is very rare. Moreover, it is of interest for neurosurgeons to observe that some cases with aneurysm at this particular site develop signs and symptoms of a lesion in the cerebellopontine angle before or after an attack of aneurysmal rupture. We experienced such a case in which the aneurysm was successfully clipped. T h e clinical course and radiologic findings in this case are presented.
Case R e p o r t A 40-year-old w o m a n experienced sudden onset of severe occipital headache, vomiting, and vertigo on January 17, 1981. She went to the emergency hospital on the day of the attack, where a lumbar puncture revealed bloody cerebrospinal fluid. On the next day, a hearing
Address reprint requests to: Dr. Kou Nakagawa, Department of Neurological Surgery, Ehime University Medical School, Shigenobucho, Onsen-Gun, Ehime, 791-02 Japan.
(c3 i984 by Elsevier Science Publishing Co., Inc.
loss on the left side and tinnitus were noted, and the patient was transferred to Ehime University Hospital. On admission, vital signs and general physical condition were not impaired. Blood pressure was 140/80 m m Hg. The patient was alert and well oriented regarding time and place. T h e r e was mild nuchal rigidity. She had a floating sensation on standing or walking, but no abnormalities were noted in the m o t o r and sensory systems. Ocular m o v e m e n t s were normal except for a horizontal nystagmus on right lateral gaze. Pupillary reactions and optic fundi were normal. T h e r e was a severe hearing loss in the left ear. W h e n the brainstem evoked responses were recorded, not all waves were obtained by stimulation from the left side (Figure 1). O t h e r cranial nerves were intact. On lumbar puncture, grossly bloody cerebrospinal fluid was obtained with an opening pressure of 180 m m H 2 0 . C o m p u t e d tomography scanning on January 18, 1981 disclosed blood in the subarachnoid space almost symmetrically. A plain x-ray film of the skull demonstrated no abnormal findings. Vertebral angiography demonstrated a saccular aneurysm of the left anterior inferior cerebellar artery extending into the internal auditory meatus, measuring 5 x 4 m m in diameter, which was most clearly revealed in the Stenver projection (Figure 2). T h e r e were no abnormalities in the angiograms of the carotid artery. The patient was kept at bed rest and treated with glycerol, dexamethasone, and antifibrinolytic drugs. H e r neurological condition was improving until the time of the operation. On January 27, 1981, a left suboccipital craniectomy was p e r f o r m e d with the patient in a sitting position. On opening the dura mater, the arachnoid m e m b r a n e was found to be thickened and slightly adherent to the dura mater. However, subarachnoid hemorrhage was not very conspicuous. After the left cerebellar hemisphere was retracted and the cerebellopontine angle explored, the seventh and eighth cranial nerves were found to be markedly compressed and pushed posteriorly close to the orifice of the internal auditory meatus by the aneu009(I-3019/84/S ~.00
232
Surg Neurol 1984;21:231-5
Nakagawa et al
Figure 1. Audiogram of brainstem evoked response, revealing absence of response on left side.
rysm. As a portion of the meatal loop of the anterior inferior cerebellar artery ran between the seventh and eighth cranial nerves and the aneurysm was adherent to the eighth nerve, it was necessary to sacrifice the latter to expose the aneurysm and the parent artery (Figure 3). A clip was applied successfully to the neck of the aneurysm within 10 minutes after temporary clipping of the anterior inferior cerebellar artery proximally. Postoperatively, the patient had a left facial palsy and tinnitus; the latter disappeared gradually. There was no other neurological deficit. Postoperative angiography confirmed complete obliteration of the aneurysm. The patient was discharged in satisfactory condition 25 days after the operation, and the facial palsy resolved completely 6 months later.
A
Discussion Since 1948, when Schwartz reported the first case o f an aneurysm of the anterior inferior cerebellar artery at the internal auditory meatus [14], only 13 such cases have appeared in the literature (Table 1) [2,3,5-11,13,15,16]. Among these cases were a few in which signs and symptoms of a lesion in the cerebellopontine angle developed gradually without any evidence of aneurysmal rupture. It was difficult to differentiate such aneurysms from tumors. In most other cases, there was sudden onset of severe headache, nausea, and vomiting caused by subarachnoid hemorrhage followed by rapid progression of palsies of the seventh and eighth cranial nerves. Acoustic neurinomas, however, may present with sudden onset of hearing loss. Therefore, an adequate investigation must be undertaken to make the diagnosis of an aneurysm when typical symptoms of aneurysmal rupture do not occur. Several authors have reported audiometric study showing fluctuation or gradual improvement of hearing loss as one useful diagnostic test in cases o f aneurysm [8,11,16]. It is important that the function o f
B Figure 2. Vertebral angiography of right side. frontal view, showing aneurysm of anterior inferior cerebellar artery at internal auditory meatus (A) that is more clearly demonstrated in Stenver projection (B).
the eighth cranial nerve be examined from time to time during the clinical course. In the present case, the patient had no complaints before rupture of the aneurysm, and an impairment of the eighth cranial nerve developed abruptly after the hemorrhage. The brainstem evoked response showed a complete disturbance of the eighth cranial nerve, although the function of the nerve was examined only once.
Aneurysm of the Anterior Inferior Cerebellar Artery
The clinical symptoms after rupture of an aneurysm are closely related to the anatomic relation of the anterior inferior cerebellar artery to the internal auditory meatus. The internal auditory artery originates from the meatal loop of the anterior inferior cerebellar artery in the vicinity of the internal auditory meatus in 5 0 - 9 0 % of cases [4,9]. As the aneurysm is assumed to develop at the junction of the anterior inferior cerebellar artery and the internal auditory artery [12], it consequently expands into the internal auditory meatus. When such an aneurysm ruptures, functional damage of the nearby cranial nerves probably arises from circulatory disturbances through vasospasm or compression by the hematoma. Detailed descriptions of the surgical treatment have been given in 12 reported cases, including the present one. In seven cases, the neck of the aneurysm was clipped; in three, the aneurysm was trapped; in one, the anterior inferior cerebellar artery was obliterated proximal to the aneurysm close to the internal auditory meatus; and in one, the aneurysm was treated by coating. Although
Figure 3. Photograph taken at operation. T__NN = t r i g e m i n a l nerve (fifth cranial nerve?: C H = cerebellar hemisphere," A I C A = anterior inferior cerebellar artery: F__NN= f a c i a l nerve (seventh cranial nero,e): A.N_N = a n e u ~ s m .
Surg Neurol 1984;21:23l-5
233
Atkinson emphasized that clipping of the anterior inferior cerebellar artery is very dangerous, especially in the portion of the meatal loop because of decreasing blood supply to the brainstem [1], the cases in which this artery was interrupted did not always develop dysfunction of the brainstem. In the present case, temporary clipping of the artery was performed with no vital changes appearing during the procedure. Perhaps circulatory disorders of the brainstem did not develop because of the anastomoses existing between the anterior inferior cerebellar artery and the posterior inferior cerebellar artery and the superior cerebellar artery. However, postoperative facial palsy and hearing loss occurred frequently in the cases treated by interruption of the anterior inferior cerebellar artery, whereas no neurological deficits were observed in those treated by clipping the neck of the aneurysm. As it is obscure whether this difference results from the involvement of the vascular system or from direct manipulation of the cranial nerves, meticulous surgical procedures for maintaining the vascular integrity of the arteries should be required to preserve the function o f the seventh and eighth cranial nerves.
234
Surg N e u r o l 1984;21:231-5
N a k a g a w a et al
T a b l e 1. Summary of Cases of Aneurysm of the Anterior Inferior Cerebellar Artery at the Internal Auditory Meatus Reference Year
Author
Age Sex
Side
Presenting signs and symptoms
F
L
Headache, vomiting, left-sided hearing loss and trigeminal palsy, nystagmus, dizziness, left-sided facial palsy, bilateral ataxia; SAH Right-sided hearing loss, tinnitus, trigeminal neuralgia, and facial palsy Headache, vomiting, left-sided facial palsy, bilateral hearing loss, tinnitus, nystagmus; SAH Confusion, headache, left-sided facial palsy, convulsion, dysphagia, diplopia; SAH Right-sided hearing loss
1948
Schwartz [14]
27
1957
Krayengbfihl & Yasargil [10] Castaigne et al
69
1967
Operation
(yr)
R
62
M
L
61
F
R
[3] 1967
Weibel et al [15]
1968 1969
Hitselberger & Gardner [7] Glasscock [5]
49
M
R
1971
Hori et al [8]
35
F
L
1973
Porter & Eyster [13]
20
F
R
1975
Benedetti et al [2]
49
F
R
1978
Johnson & Kline [9] Higuchi et al
54
M
R
53
M
L
1978
R
[6] 1978
Mori et al [11]
48
M
R
1982
Zlomik et al [16]
44
F
L
1983
Present case
40
F
L
Procedure
Complications
Trapping
None
Trapping
Complete deafness on left, facial palsy Death of acute necrosis of liver
Clipping
Clipping
Right-sided hearing loss, Clipping dizziness, inappropriate lacrimation on right Headache, vomiting, left-sided Trapping facial palsy, nystagmus, leftsided hearing loss and tinnitus; SAH Stupor, headache, right-sided hearing loss and facial palsy, vertigo, right-sided hemiparesis; SAH Headache, vomiting, right-sided Clipping ? facial palsy and hearing loss, dizziness, lateropulsion; SAH Confusion, headache, right-sided Obliteration facial palsy and twitching; SAH of AICA Headache, vomiting, left-sided Clipping tinnitus; SAH Right-sided hearing loss, vertigo, Coating nystagmus Left-sided hearing loss, tinnitus, Clipping and trigeminal palsy, nystagmus, vertigo Headache, vomiting, left-sided Clipping hearing loss and tinnitus, nystagmus; SAH
None None
Complete deafness on left
Aggravation of facial palsy and hearing lOSS Right-sided hearing lOSS Right-sided hearing loss and tinnitus None None
None
Abbreviations: yr = year; F = female; L = left; R = right; M = male; AICA = anterior inferior cerebellar artery; SAH = subarachnoid hemorrhage.
References 1. AtkinsonWJ. The anterior inferior cerebellar artery: Its variation, pontine distribution and significance in surgery of cerebellopontine angle tumours. J Neurol Neurosurg Psychiatry 1949; 12:137-51. 2. Benedetti A, Curri D, Carbonin C. Aneurysm of the internal auditory artery revealed by a partial cerebellopontine angle syndrome. Neurochirurgia (Stuttg) 1975;18:126-30.
5. 6. 7. 8.
3. Castaigne P, Pertuiset B, Cambier J, Brunet P. Andvrisme de l'art~re auditive interne rdvdld par une paralysie faciale recidivante. Cure radicale. Presse Med 1967;75:2493-6.
9.
4. Fisch U. The surgical anatomy of the so-called internal auditory artery. In: Hamberger CA, Wersiill J, eds. Disorders of the skull
10.
base region: Proceedings. New York: Wiley-Interscience, 1969:121-30. Glasscock ME. Middle fossa approach to the temporal bone. An otologic frontier. Arch Otolaryngol 1969;90:15-27. Higuchi H, Yajima K, Nakazawa S. A case of aneurysm of the left internal acoustic meatus. No Shinkei Geka 1978;4:401-4. Hitselberger WE, Gardner G Jr. Other tumors of the cerebellopontine angle. Arch Otolaryngol 1968;88:712-4. Hori T, Hirakawa K, Ishijima B, Manaka S, Fukushima T, Shimizu N, Sato T. Aneurysm in the internal auditory meatus. Case report. J Neurosurg 1971;35:605-9. Johnson JH, Kline DG. Anterior inferior cerebellar artery aneurysms. J Neurosurg 1978;48:455-60. Krayenbfihl H, Yasargil MG. Die vaskuli~ren Erkrankungen im
A n e u r y s m o f the A n t e r i o r I n f e r i o r C e r e b e l l a r A r t e r y
Surg N e u r o l 1984;21:231-5
235
Gebiet der Arteria vertebralis und Arteria basialis. Stuttgart: Georg Thieme, 1957.
14. Schwartz HG. Arterial aneurysm of the posterior fossae. J Neurosurg 1948;5:312-6.
11. Mori K, Miyazaki H, Baba M, Kumagami H. Aneurysm in the cerebello-pontine angle and hearing loss. No Shinkei Geka 1978;6:845-53.
15. Weibel J, Fields WS, Campos RJ. Aneurysms of the posterior cervicocranial circulation: Clinical and angiographic considerations. J Neurosurg 1967;26:223-34.
12. Pia HW. Classification ofvertebral-basilar aneurysms. Acta Neurochir IWien) 1979;47:3-30.
16. Zlotnik El, Sklyut AS, Smejanovich AF, Stasenko EN. Saccular aneurysm of the anterior inferior cerebellar internal auditory artery: Case report. J Neurosurg 1982;57:829-32.
13. Porter RJ, Eyster EF. Aneurysms in the anterior inferior cerebellar artery at the internal acoustic meatus: Report of a case. Surg Neurol 1973;1:27-8.