摘要:

Summary:The therapeutic options for brain-stem vascular malformations have expanded, and postoperative morbidity has declined, with renewed interest in skull base surgery, surgical lasers, electrophysiologic stimulation of cranial nerve nuclei, intraoperative ultrasound, and intraoperative angiography. This article reviews experience (1984–1993) in evaluating the long-term results of 63 patients with brain-stem vascular malformations; 27 patients were treated surgically, and 36 were observed. There were 45 cavernous angiomas, 13 arteriovenous malformations (AVMs), five capillary telangiectasias, and nine associated venous angiomas. Forty-one (65%) of 63 were located in the pons. Hemorrhage was the initial presentation in 54 (86%) patients; 23 (42.5%) suffered repeat hemorrhages. Surgery was performed when the malformation was near the brain-stem surface, when the neurologic status deteriorated, and in cases of repeat hemorrhage. Resection of venous angiomas was avoided. Of 27 surgical patients, 15 (56%) had transient worsening of their neurologic status and five (18.5%) suffered permanent neurologic deficits that included truncal ataxia, internuclear ophthalmoplegia, abducens palsy, paralysis of upward gaze, and nuclear facial weakness. Two patients (13.5%) suffered a recurrent hemorrhage from residual malformation. There was no mortality. Neurologic improvement occurred in 23 (85%) surgical patients, and 24 (89%) returned to independent living with functional neurologic capacity. Results improved with surgical experience and technical advances, leading the authors to conclude that surgical treatment is the best option for brain-stem vascular malformations. Observation is reserved for deep-seated and asymptomatic cavernous angiomas; stereotactic radiosurgery is preferred for intraparenchymal AVMs and unruptured AVMs of the tectum and ventral brain stem.

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Summary:The pathogenesis of syringomyelia of Arnold-Chiari malformation (ACM) has been debated for decades. Theories abound; each fits some cases, but none fits all. Recently, it seems clear that the herniation of the cerebellar tonsils into the foramen magnum is the most constant feature of ACM. The herniated cerebellar tonsils at the foramen magnum may induce three events: (a) a check-valve effect at the central canal of the spinal cord, (b) a functional occlusion of the subarachnoid space at the foramen magnum, and (c) a functional occlusion of the foramen of Magendie due to mass effect, scarring arachnoiditis, or both. Mathematically, eight pathological possibilities may spring from the three events. An analysis of the eight pathological possibilities comes to the conclusion that a block of the subarachnoid space at the foramen magnum is a prerequisite for the pathogenesis of syringomyelia. The hydrodynamic theory of Gardner is applicable to one of the conditions where the outlet of the fourth ventricle is inadequate and the check-valve effect at the central canal of the spinal cord is absent. The therapeutic implications from such a conclusion are discussed.

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

Summary:Paragangliomas are tumors that originate from the paraganglia tissue, which belongs to the extraadrenal chromaffin tissue. The glomus jugulare tumor is the most common benign tumor of the middle ear and the second most common tumor of the temporal bone. Hearing loss and pulsatile tinnitus are the most common symptoms of these tumors. The intravagale paraganglioma is a rare tumor of the head and neck, accounting for only 5% of the paragangliomas that occur in that area. A painless mass in the high neck with extension into the parapharyngeal space is the most common symptom of this tumor, which also has a striking tendency to be multicentric. Care must be taken to distinguish between glomus jugulare and carotid body or intravagale tumors. Likewise, the diagnosis of pheochromocytoma is crucial to avoid severe disarrangement in the perioperative period. Location in the jugular foramen with extension into the middle ear, neck, and intracranial space are pathognomonic of glomus jugulare tumors, but because occasionally meningiomas or neurinomas mimic these glomus tumors, an angiogram is necessary for obtaining an accurate diagnosis. Superselective embolization with absorbable material is an adjuvant therapy to surgery for glomus jugulare tumors, but meticulous care must be used to avoid the passage of embolic material into the arterial anastomoses of the vertebral artery with ascending pharyngeal artery and occipital artery. Despite numerous descriptions given in the literature concerning the efficacy of radiotherapy for controlling the growth of paragangliomas, the histological findings of these irradiated specimens have shown that the chief cells are not effectively affected by radiotherapy. Hence, the only curative treatment for paragangliomas is total resection. With current technique and management, this can be achieved without incidence of morbidity or mortality.

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID

ISSN:1050-6438    

出版商:OVID    

年代:1995

数据来源: OVID