J Neurosurg 48:639-641, 1978
Foramen magnum syndrome caused by a giant aneurysm of the posterior inferior cerebral artery Case report
DONALD JUDICE, M.D., AND EDWARD S. CONNOLLY, M.D. Department of Neurosurgery, Ochsner Medical Institutions, New Orleans, Louisiana
The authors present a case of giant aneurysm of the posterior inferior cerebellar artery. It was successfully excised with reversal of neurological deficits. KEY WORDS giant intracraniai aneurysm cerebellar artery aneurysm "
G
IANT intracranial aneurysms are not uncommon, accounting for about 5% of all intracranial aneurysmsr however, giant aneurysms of the posterior inferior cerebellar artery are quite rare. 2,7 We have found only two cases reported in English. The following is a third case that presented the syndrome of a foramen magnum mass. Case Report
This 70-year-old woman had a 7-month history of suboccipital headaches beginning after an automobile accident. The headache gradually worsened and was aggravated when she lay down. She next noticed a numbness and burning sensation in both hands, followed soon by weakness in both hands and arms. This progressed to the point that she could not feed herself without assistance. Just before examination, numbness and progressive weakness in both legs had developed. She required assistance to walk and had fallen several times. She retained bowel and bladder control. J. Neurosurg. / Volume 48 / April, 1978
9 foramen magnum syndrome
Examination. On admission the patient was alert but agitated. She was oriented but had poor recent m e m o r y and was easily confused. She was weak in all four extremities; the arms were weaker than the legs, and the right side weaker than the left. She was diffusely hyperreflexic with unsustained clonus in both ankles. Pinprick sensation was present throughout with hyperalgesia in both hands. Vibratory sensation was absent in both hands and below the sternum. Position sensation was absent in both hands and impaired in both feet. Her gait was broad-based and spastic; she required a walker to ambulate. She demonstrated very poor finger-to-nose and toe-tapping tests bilaterally. She had bilateral Babinski signs. Routine blood and urine studies were considered normal. Plain skull, cervical spine, and chest films were read as normal. Computerized t o m o g r a p h y of the head revealed no abnormality. A myelogram revealed a large mass in the foramen magnum that appeared to arise from the left, posteriorly. Cerebrospinal fluid (CSF) pressure and manometrics
639
D. J u d i c e
F[c. 1. Operative photograph showing giant aneurysm about 4 cm in diameter arising from the left posterior inferior cerebellar artery.
were normal; C S F protein was 79 m g / 1 0 0 ml. Vertebral angiography revealed a small blush in the area of the foramen magnum. A diagnosis of a foramen m a g n u m mass was made and surgical treatment was instituted. Operation. A round, smooth, bluish mass was seen displacing the cerebellum and the brain stem to the right and forward. Inspection and palpation revealed it to be a giant aneurysm, about 4 cm in diameter, arising from the left posterior inferior cerebellar artery (Fig. 1). By needle decompression and dissection around the aneurysm, we were able to place a Heifetz clip across the neck and then excise the aneurysm. After excision, the aneurysm was found to contain a large thrombus. The patient improved remarkably. Within a week she was able to walk with a cane, and upon release 2 weeks after operation, she was feeding herself without difficulty. Three months following operation all neurological signs and s y m p t o m s had cleared. 640
a n d E. S. C o n n o l l y
FIG. 2. Location of 98 reported giant aneurysms. The present case report is not included. A.C.A. = anterior cerebral artery; A.Co.A. = anterior communicating artery; Ophthal. A. = ophthalmic artery; M.C.A. = middle cerebral artery; P.C.A. = posterior communicating artery; S.C.A. = superior cerebellar artery; I.C.A. = internal carotid artery; P.I.C.A. = posterior inferior cerebellar artery; V.A. = vertebral artery.
Discussion G i a n t intracraniat aneurysms by definition are those that are greater than 2.5 cm in diameter. They most often present s y m p t o m s of mass lesions 1,'-7 as compared to smaller aneurysms that present s y m p t o m s of acute subarachnoid hemorrhage. Figure 2 illustrates the location of the giant aneurysms found in the literature. 1,5,7 The clinical presentation of giant aneurysm is quite varied and seldom leads to the diagnosis. T h e c o m m o n e s t s y m p t o m is headache, 1,z,48 and the c o m m o n e s t sign is cranial nerve palsy? ,3,4,8,7 However, giant aneurysms can produce a varied neurological picture. In the diagnosis of giant aneurysms, plain films are helpful in from 36% 7 to 45% 5 of cases, showing skull erosion, calcification, or both. P n e u m o e n c e p b a l o g r a p h y is beneficial in a b o u t 50% of the cases in which it is perf o r m e d ? ,7 Air studies with planigrams tend to
J. Neurosurg. / Volume 48 / April, 1978
Giant aneurysm of the PICA localize the lesions and give a m o r e accurate idea of their true size. Positive contrast studies m a y be helpful with posterior fossa and foramen m a g n u m lesions, as they were with our patient. Computerized t o m o g r a p h y has proven to be of benefit in some instances, 3a but was not helpful in our case. Contrast angiography is considered the diagnostic procedure of choice. It will lead to the correct diagnosis in the majority of cases, but care must be taken in the interpretation of these studies because giant aneurysms frequently contain large mural clots and m a y fill very poorly. In our case, the angiogram was interpreted as a possible h e m a n g i o b l a s t o m a with an associated cyst. The often stated rule that giant aneurysms do not bleed is not true, as demonstrated in the larger series of cases. 1,5a An average of 30% of patients will present s y m p t o m s and signs of subarachnoid h e m o r r h a g e or give a history consistent with a previous hemorrhage. The t r e a t m e n t of choice for giant aneurysm is surgical ligation and excision, if technically feasible. Other successful forms of therapy have been ligation with and without decompression of the aneurysmal sac, thrombosis, and simple decompression by craniectomy with or without resection of silent areas of adjacent brain.
J. Neurosurg. / Volume 48 / April. 1978
References
1. Bull J: Massive aneurysms at the base of the brain. Brain 92:535-570, 1969 2. Jane JA: A large aneurysm of the posterior inferior cerebellar artery in a 1-year-old child. J Neurosurg 18:245-247, 1961 3. Maxwell RE, Chou SN: Aneurysmal tumors of the basifrontal region. J Neurosurg 46:438-445, 1977 4. Michael WF: Posterior fossa aneurysms simulating tumours. J Neural Neurasurg Psychiatry 37:218-223, 1974 5. Morley TP, Barr HWK: Giant intracranial aneurysms: diagnosis, course and management. Clin Neurosurg 16:73-94, 1969 6. Pribram HFW, Hudson JD, Joynt R J: Posterior fossa aneurysms presenting as mass lesions. Am J Roentgenol Radium Ther Nucl Med 105:334-340, 1969 7. Sarwar M, Batnitzky S, Schechter MM: Tumorous aneurysms. Neuroradiology 12:7997, 1976
Address reprint requests to: Edward S. Conholly, M.D., Ochsner Clinic, 1514 Jefferson Highway, New Orleans, Louisiana 70121.
641
Foramen magnum syndrome caused by a giant aneurysm of the posterior inferior cerebral artery Case report
DONALD JUDICE, M.D., AND EDWARD S. CONNOLLY, M.D. Department of Neurosurgery, Ochsner Medical Institutions, New Orleans, Louisiana
The authors present a case of giant aneurysm of the posterior inferior cerebellar artery. It was successfully excised with reversal of neurological deficits. KEY WORDS giant intracraniai aneurysm cerebellar artery aneurysm "
G
IANT intracranial aneurysms are not uncommon, accounting for about 5% of all intracranial aneurysmsr however, giant aneurysms of the posterior inferior cerebellar artery are quite rare. 2,7 We have found only two cases reported in English. The following is a third case that presented the syndrome of a foramen magnum mass. Case Report
This 70-year-old woman had a 7-month history of suboccipital headaches beginning after an automobile accident. The headache gradually worsened and was aggravated when she lay down. She next noticed a numbness and burning sensation in both hands, followed soon by weakness in both hands and arms. This progressed to the point that she could not feed herself without assistance. Just before examination, numbness and progressive weakness in both legs had developed. She required assistance to walk and had fallen several times. She retained bowel and bladder control. J. Neurosurg. / Volume 48 / April, 1978
9 foramen magnum syndrome
Examination. On admission the patient was alert but agitated. She was oriented but had poor recent m e m o r y and was easily confused. She was weak in all four extremities; the arms were weaker than the legs, and the right side weaker than the left. She was diffusely hyperreflexic with unsustained clonus in both ankles. Pinprick sensation was present throughout with hyperalgesia in both hands. Vibratory sensation was absent in both hands and below the sternum. Position sensation was absent in both hands and impaired in both feet. Her gait was broad-based and spastic; she required a walker to ambulate. She demonstrated very poor finger-to-nose and toe-tapping tests bilaterally. She had bilateral Babinski signs. Routine blood and urine studies were considered normal. Plain skull, cervical spine, and chest films were read as normal. Computerized t o m o g r a p h y of the head revealed no abnormality. A myelogram revealed a large mass in the foramen magnum that appeared to arise from the left, posteriorly. Cerebrospinal fluid (CSF) pressure and manometrics
639
D. J u d i c e
F[c. 1. Operative photograph showing giant aneurysm about 4 cm in diameter arising from the left posterior inferior cerebellar artery.
were normal; C S F protein was 79 m g / 1 0 0 ml. Vertebral angiography revealed a small blush in the area of the foramen magnum. A diagnosis of a foramen m a g n u m mass was made and surgical treatment was instituted. Operation. A round, smooth, bluish mass was seen displacing the cerebellum and the brain stem to the right and forward. Inspection and palpation revealed it to be a giant aneurysm, about 4 cm in diameter, arising from the left posterior inferior cerebellar artery (Fig. 1). By needle decompression and dissection around the aneurysm, we were able to place a Heifetz clip across the neck and then excise the aneurysm. After excision, the aneurysm was found to contain a large thrombus. The patient improved remarkably. Within a week she was able to walk with a cane, and upon release 2 weeks after operation, she was feeding herself without difficulty. Three months following operation all neurological signs and s y m p t o m s had cleared. 640
a n d E. S. C o n n o l l y
FIG. 2. Location of 98 reported giant aneurysms. The present case report is not included. A.C.A. = anterior cerebral artery; A.Co.A. = anterior communicating artery; Ophthal. A. = ophthalmic artery; M.C.A. = middle cerebral artery; P.C.A. = posterior communicating artery; S.C.A. = superior cerebellar artery; I.C.A. = internal carotid artery; P.I.C.A. = posterior inferior cerebellar artery; V.A. = vertebral artery.
Discussion G i a n t intracraniat aneurysms by definition are those that are greater than 2.5 cm in diameter. They most often present s y m p t o m s of mass lesions 1,'-7 as compared to smaller aneurysms that present s y m p t o m s of acute subarachnoid hemorrhage. Figure 2 illustrates the location of the giant aneurysms found in the literature. 1,5,7 The clinical presentation of giant aneurysm is quite varied and seldom leads to the diagnosis. T h e c o m m o n e s t s y m p t o m is headache, 1,z,48 and the c o m m o n e s t sign is cranial nerve palsy? ,3,4,8,7 However, giant aneurysms can produce a varied neurological picture. In the diagnosis of giant aneurysms, plain films are helpful in from 36% 7 to 45% 5 of cases, showing skull erosion, calcification, or both. P n e u m o e n c e p b a l o g r a p h y is beneficial in a b o u t 50% of the cases in which it is perf o r m e d ? ,7 Air studies with planigrams tend to
J. Neurosurg. / Volume 48 / April, 1978
Giant aneurysm of the PICA localize the lesions and give a m o r e accurate idea of their true size. Positive contrast studies m a y be helpful with posterior fossa and foramen m a g n u m lesions, as they were with our patient. Computerized t o m o g r a p h y has proven to be of benefit in some instances, 3a but was not helpful in our case. Contrast angiography is considered the diagnostic procedure of choice. It will lead to the correct diagnosis in the majority of cases, but care must be taken in the interpretation of these studies because giant aneurysms frequently contain large mural clots and m a y fill very poorly. In our case, the angiogram was interpreted as a possible h e m a n g i o b l a s t o m a with an associated cyst. The often stated rule that giant aneurysms do not bleed is not true, as demonstrated in the larger series of cases. 1,5a An average of 30% of patients will present s y m p t o m s and signs of subarachnoid h e m o r r h a g e or give a history consistent with a previous hemorrhage. The t r e a t m e n t of choice for giant aneurysm is surgical ligation and excision, if technically feasible. Other successful forms of therapy have been ligation with and without decompression of the aneurysmal sac, thrombosis, and simple decompression by craniectomy with or without resection of silent areas of adjacent brain.
J. Neurosurg. / Volume 48 / April. 1978
References
1. Bull J: Massive aneurysms at the base of the brain. Brain 92:535-570, 1969 2. Jane JA: A large aneurysm of the posterior inferior cerebellar artery in a 1-year-old child. J Neurosurg 18:245-247, 1961 3. Maxwell RE, Chou SN: Aneurysmal tumors of the basifrontal region. J Neurosurg 46:438-445, 1977 4. Michael WF: Posterior fossa aneurysms simulating tumours. J Neural Neurasurg Psychiatry 37:218-223, 1974 5. Morley TP, Barr HWK: Giant intracranial aneurysms: diagnosis, course and management. Clin Neurosurg 16:73-94, 1969 6. Pribram HFW, Hudson JD, Joynt R J: Posterior fossa aneurysms presenting as mass lesions. Am J Roentgenol Radium Ther Nucl Med 105:334-340, 1969 7. Sarwar M, Batnitzky S, Schechter MM: Tumorous aneurysms. Neuroradiology 12:7997, 1976
Address reprint requests to: Edward S. Conholly, M.D., Ochsner Clinic, 1514 Jefferson Highway, New Orleans, Louisiana 70121.
641
