Spinal arachnoid cysts: Clinical and radiological correlation with prognosis

Summary The clinical and radiological findings in six extradural and nine intradural arachnoid cysts are discussed in relation to previous reports. Only two cysts failed to opacify during positive contrast myelography; in both cases Myodil was used and in one of them contrast medium had entered the cyst on delayed films taken at 24 h. Pain was always improved and generally cured by operation, only two patients having some residual backache. There was permanent improvement of neurological function in only eight cases. The factors associated with poor permanent recovery after surgical treatment were: 1) very marked thinning of the spinal cord by the cyst, and 2) relatively longer duration of paresis-only one case had paresis for under 2 years (mean 4.8 years) compared with only two cases for over 1 year (mean 2 years) in those with good recovery.     

Intracranial arachnoid cysts in myotonic dystrophy

Summary Clinically apparent brain dysfunction is common in myotonic dystrophy. In a sample of fourteen adult patients with the definite form of this disease, brain magnetic resonance imaging detected frequent white matter abnormalities and ventriculomegaly. In addition, two patients exhibited an intracranial arachnoid cyst, a condition of neurosurgical interest that could be related to the generalized dysmaturational process present in this disease. Patients with myotonic dystrophy deserve a careful screening for brain involvement. Further MRI studies should ascertain the actual prevalence of brain anomalies in myotonic dystrophy and define the role of this procedure in the workup of this disease.     

Magnetic resonance imaging of arachnoid cysts

A retrospective review of magnetic resonance imaging (MRI)—computed tomography (CT) correlation was performed in 29 patients with arachnoid cysts. Short TR, short TE spin echo (SE) pulse sequences provided the best anatomic definition whereas multiple echo long TR, TE sequences allowed comparison of the signal intensity of the cyst with that of cerebrospinal fluid (CSF). Simple arachnoid cysts were isointense while neoplastic, hemorrhagic or inflammatory cysts were hyperintense relative to CSF. The CT differential diagnosis of an arachnoid cyst (depending upon its location) may include other cystic collections such as craniopharyngioma, epidermoid, astrocytoma, and chronic subdural hematoma. However, on MRI the combination of extraaxial location, morphological features, and signal intensity matching that of CSF allows one to make the diagnosis of an uncomplicated arachnoid cyst with confidence.     

Computed tomography of arachnoid cysts.

The typical CT appearance of intracranial arachnoid cysts may obviate additional neuroradiological procedures. Ventriculography using water-soluble contrast media may differentiate a suprasellar arachnoid cyst from a dilated third ventricle. Twelve cases are presented.     

MR imaging of intracranial arachnoid cysts

The magnetic resonance characteristics of 16 intracranial arachnoid cysts were evaluated and several features identified that allowed the differentiation from other cystic lesions. Uncomplicated arachnoid cyst contents respond like CSF to both T1 and T2 weighted sequences. Signal from the contiguous brain is of normal intensity. The absence of signal from cortical bone and the ease of obtaining multiplanar views enable the margins of the cyst, its contents, and the full extent of the lesion to be easily defined.     

Bilateral arachnoid cysts of the temporal fossa in four children with glutaric aciduria type I

Glutaric aciduria type I is an uncommon inborn error of metabolism. It is a serious disease, often with a fatal outcome. This study reports the presence of bilateral temporal fluid collections, probably bilateral arachnoid cysts, in association with glutaric aciduria type I. The CT and, when available, MR studies from five patients with this disorder were reviewed. Four of the patients had findings consistent with bilateral arachnoid cysts of the temporal fossa. This is a rare occurrence, with only 11 such cases reported in the literature. The observed association between temporal fluid collections and glutaric aciduria type I suggests that patients with bilateral arachnoid cysts should be investigated for this metabolic disorder.     

MR imaging of thoracic extradural arachnoid cysts

Two extradural arachnoid cysts of the thoracic spine were studied with magnetic resonance imaging, myelography, and CT. Magnetic resonance imaging correctly characterized the extradural location of the cysts as well as the cyst contents as CSF, thus establishing the diagnosis. Magnetic resonance is helpful in the assessment of the extent of cord atrophy and myelomalacia and may be of predictive value in the postoperative prognosis.     

Metrizamide-enhanced computed tomography of intracranial arachnoid cysts

Between July 1981 and August 1983 the authors studied 21 patients with intracranial arachnoid cysts using metrizamide-enhanced CT. With this method we are able to determine the degree of communication between the cysts and the surrounding subarachnoid space as well as to assess the evolving character of some of these lesions. This information will allow a more rational choice of surgical treatment.     

Diffuse arachnoid ossification and multiple arachnoid cysts presenting with progressive thoracic myelopathy

An ossified arachnoid membrane combined with cystic formation is rarely reported as a cause of spinal cord compression. We report the case of a 60-year-old man who presented with diffuse ossification of the arachnoid membrane (arachnoid ossification) and multiple cystic changes (arachnoid cyst) at the thoracic and lumbar spine. The lesions were surgically removed and progressive deterioration was prevented, although no marked improvement of neurological symptoms was attained.     

Dynamic study of arachnoid cysts with metrizamide

Summary Intracranial arachnoid cysts do not usually present diagnostic problems when studied by CT, since they appear as low density images similar to those produced by CSF, do not change on intravenous contrast perfusion, and are located extraparenchymatously. Sometimes, however, their diagnosis can become difficult or doubtful mainly in cases of deep, basal or paramedian cysts [12, 18, 22, 24]. on the other hand, the functional or dynamic aspects of these structures remain unkown when the study is limited to simple CT. Computed cysternography with metrizamide (CCM) and time control will not only show the relationship between these structures and the arachnoid space but also their dynamic aspect, which may determine the surgical treatment.     

Lumbar arachnoid cysts: 2 unusual cases]

Two cases of arachnoid cyst in the lumbar region are described. One is intradural, acquired, and associated to severe arachnoiditis while the other is extradural in location and probably congenital. The interest of myelography, CT myelography, and MRI for the diagnosis is discussed.     

Cervical neuroma associated with multiple intracranial arachnoid cysts

Summary A case of dumbbell cervical neuroma associated with multiple intracranial arachnoid cysts is described.     

Suprasellar arachnoid cysts: 1. CT recognition

Suprasellar arachnoid cysts are basal midline masses that represent a rare but surgically remediable cause of hydrocephalus and neurologic deficits. These cysts represent a diagnostic challenge and often go unrecognized for many years. The authors review the computed tomographic (CT) findings in seven patients with documented suprasellar arachnoid cysts and define previously undescribed diagnostic criteria. These cysts usually can be differentiated from cystic midline neoplasms by their CT density, homogeneity, and location as well as by their lack of fat, lack of calcification, and absence of contrast enhancement. Accurate distinction from marked third-ventricular enlargement secondary to obstructive hydrocephalus and from third-ventricular ependymal cysts can be made on the basis of basal cisternal expansion, distinctive mass effect and displacement, the characteristic shape and contour of the apparent "third ventricle," and the appearance of structures at the foramen of Monro. Although metrizamide CT ventriculography and cisternography allow confirmation of the diagnosis and evaluation of cerebrospinal fluid dynamics, these definitive studies will not be obtained unless the cysts are first suspected by their conventional CT appearance.     

手术治疗颅内蛛网膜囊肿45例

目的:报告45内蛛网膜囊肿(IAC),对其临床表现.诊断.手术适应证.手术方法选择和术中注意事项进行了讨论。方法:回顾性分析我院1995年5月~2003年12月收治的45例颅内蛛网膜囊肿。结果:手术45例在术后囊腔均缩小或消失,颅高压解除,症状消失。结论:ICA约占颅内占位性病变的⒈17%,最常见于外侧裂池。CT.MRI是最可靠的诊断方法。凡囊肿有颅内高压者,充分建立囊腔与周围脑池或腹腔之间的交通是手术成功的关键。     

手术治疗颅内蛛网膜囊肿45例

蛛网膜囊肿(ICA)约占颅内占位性病变的1%[1],自1995年5月至2003年12月期间收治的45例颅内蛛网膜囊肿,并讨论如下。1资料与方法1.1一般资料男30例,女15例。年龄2岁~52岁,20岁以下25例。病程1月~12年不等。13例有头部外伤史,外伤至发病时间:10天~4年不等。ICA发生部位:外侧裂池22