Extradural hematoma complicating middle fossa arachnoid cyst

Two cases of post-traumatic extradural hematoma complicating an arachnoid cyst of the middle cranial fossa in children are described. While subdural and intracystic hemorrhages are well-known complications from this malformation, the association with extradural hematoma has never been previously reported in the literature. The pathogenetic mechanisms are discussed and the particular vulnerability of intracranial arachnoid cysts is stressed.     

Effective shunt-independent treatment for primary middle fossa arachnoid cyst

The results of a prospective study on excision of the outer and inner membrane for symptomatic primary middle fossa arachnoid cysts in children are presented. During the period 1982–1989, among 48 cases of cyst in various locations, 18 symptomatic patients were treated by excision of both the outer and inner membranes with an opening to the basal cistern. The mean patient age was 3.2 years. All patients were evaluated by examinations, including magnetic resonance imaging (MRI), X-ray computed tomography (CT), quantitative CT cisternography (CTC), digital substraction angiography (DSA), N-isopropyl-p[123]iodoamphetamine single-photon emission CT (IMP-SPECT) and IQ. All showed abnormal cerebrospinal fluid flow dynamics. Significant complications included massive subdural effusion in two patients and transient pulmonary edema in one. There were no recurrences during the follow-up period (mean 4.7 years). Two morphological types were noted: type I, the classical anteromedial type where the cysts are attached directly to the adjacent parasellar cisterns, and type II, the anterolateral type, where the diagonally concave anterior temporal lobe covers the adjacent cisterns, making wide opening difficult. Type I accounted for 78% of all cases, and the reduction of the cyst volume with clinical improvement was remarkable within 6 months after surgery. Angiographically, 22% of cases showed tapering and retrograde filling of the superficial middle cerebral vein. This pattern is not included in Hacker's normal variations [18] and suggest mild but chronic compression of the developing brain. Even in patients with hemispheric cyst, the reconstituted brain showed sufficient cerebral perfusion on SPECT, suggesting that the nature of this disease entity is reversible developmental arrest. These results confirm that excision is a safe, effective shunt-independent procedure for middle-fossa arachnoid cysts, especially for those of type I.     

The clinical classification and treatment of middle cranial fossa arachnoid cysts in children

Objective

The optimal management for middle fossa arachnoid cysts (MFAC) remains controversial, but cystocistern fenestration is effective. MFACs are divided into non-communicating arachnoid cysts (NCIAC) and communicating arachnoid cysts (CIAC). This retrospective observational study evaluated the role of phase-contrast cine magnetic resonance imaging (PC-MRI) in the diagnosis and postoperative evaluation of MFACs and assessed surgical outcomes.

Methods

Twenty-eight children with MFAC that were diagnosed by conventional neuroradiology were enrolled. PC-MRI was performed preoperatively. The clinical manifestations, cyst volumes and PC-MRI data were analyzed, and the flow of cerebrospinal fluid (CSF) at the fistula was qualitatively evaluated.

Results

No communication with the adjacent subarachnoid space was found on preoperative PC-MRI in 20 patients, and they were diagnosed with NCIAC. A statistically significant decrease in cyst volume was observed in all 20 patients postoperatively. Symptoms resolved or improved in the 14 patients who were symptomatic preoperatively, and a positive CSF flow was found in all 20 patients postoperatively. PC-MRI diagnosed eight patients with CIAC, and the cyst sizes did not increase during follow-up.

Conclusions

Cystocistern fenestration is an effective treatment for children with lateral fissure IAC. PC-MRI can be used to determine the IAC type and to evaluate the effectiveness of cystocistern fenestration.     

Intraoperative subdural hematoma in a patient with arachnoid cyst in the middle cranial fossa

A case of arachnoid cyst in the middle cranial fossa complicated by intraoperative subdural hemorrhage is presented. Accumulation of cerebrospinal fluid (CSF) outside the outer wall of the arachnoid cyst was found to induce the rupture of well-developed, fragile leptomeningeal vessels at the base of the middle cranial fossa. This phenomenon is noteworthy as a pitfall in surgery for intracranial arachnoid cyst and suggest the bleeding source of subdural hematoma occasionally associated with this lesion.     

Development of a middle fossa arachnoid cyst A theory on its pathogenesis

The progression of congenital arachnoid cysts has seldom been documented. We report the case of a child who was diagnosed with arrested hydrocephalus at the age of 13 months. Neuroimaging studies performed when the girl was 22 months old showed the appearance of an arachnoid cyst in the right middle fossa, while the previously enlarged ventricles seemed to have decreased in size. To the best of our knowledge, the paradoxical expansion of an arachnoid pouch following a reduction in the size of the ventricular system has not previously been documented. We advance the hypothesis that the development of some cases of arachnoid cyst might be pathogenically related to impaired CSF dynamics associated with pre-existing hydrocephalus. We also briefly review the pertinent literature on the formation and evolution of congenital cerebral arachnoid cysts. Received: 4 September 1998     

Transient global amnesia associated with a large arachnoid cyst of the middle cranial fossa of the non dominant hemisphere

A case of transient global amnesia associated with an arachnoid cyst occupying the middle cranial fossa of the non dominant hemisphere is reported. The relationship between the two conditions is discussed and the value of CT brain scanning in patients with TGA emphasized.

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Sommario è descritto un caso di amnesia globale transitoria associato ad una cisti aracnoidea occupante la fossa cranica media dell'emisfero non dominante. Viene discussa la relazione fra le due patologie. L'utilità della TAC cerebrale nei pazienti con AGT è rimarcata.

     

Posttraumatic intradiploic arachnoid cyst of the posterior fossa

We report the case of a 5-year-old girl with an enlarging suboccipital mass, a posttraumatic intraosseous arachnoid cyst. Diagnostic work-up revealed that the lesion consisted of an intradiploic arachnoid cyst and an extra-axial occipital pouch that communicated by way of an osseous and dural defect. Surgical repair was undertaken with good results. A search of the current literature has shown only seven previous reports of leptomeningeal cysts situated at the occipital bones, most of them the result of an antecedent skull fracture. A pathogenetic hypothesis is presented comparing the growth of arachnoid intraosseous cysts and the development of meningocencephaloceles. Received: 1 October 1996     

囊肿-腹腔分流术治疗儿童中线部位巨大蛛网膜囊肿

目的 总结囊肿-腹腔分流手术治疗儿童中线部位巨大蛛网膜囊肿的临床经验.方法 回顾性分析2005年1月至2011年12月应用囊肿-腹腔分流手术治疗的儿童中线部位巨大蛛网膜囊肿的临床资料,总结分析其发病特点合并畸形及预后情况.结果 17例患儿接受囊肿-腹腔分流手术,多因头围增大就诊或孕期超声发现囊肿,多伴有邻近脑组织的发育不良,可有一定程度的生长发育落后,经分流手术后症状消失,发育改善.结论 儿童中线部位巨大蛛网膜囊肿早期进行分流手术简单、有效,预后较好.     

显微外科治疗颅内蛛网膜囊肿的疗效观察

目的 探讨显微手术治疗颅内蛛网膜囊肿的效果。方法 回顾性分析42例颅内蛛网膜囊肿患者采用显微手术治疗的疗效。结果 囊肿全切除23例,大部切除14例,部分切除加脑池交通术5例。术后复查CT,29例囊肿消失或明显缩小。平均随访1年,患者症状与体征均改善。结论 显微手术治疗蛛网膜囊肿疗效满意。充分建立囊腔与脑池和蛛网膜下腔的交通,是手术成功的关键。     

中颅窝蛛网膜囊肿的临床特点及外科治疗

目的 探讨中颅窝蛛网膜囊肿的临床特点及不同术式对其治疗的临床疗效.方法 回顾性分析第四军医大学西京医院神经外科自2001年5月至2008年5月收治的352例中颅窝蛛网膜囊肿患者(占同期收住的颅内占位性病变患者的2.58%)的临床资料、手术方式及预后情况,其中男性发病率明显高于女性(男:女为4.1∶1),以左侧居多(左∶右为3.6∶1),324例行囊肿切除术,28例巨大囊肿行囊肿-腹腔分流术.结果 术后平均随访3个月～3年.头痛就诊患者中75例(58.59%)术后头痛完全消失,41例(32.03%)明显缓解.癫痫发作患者中8例术后发作频率明显减少或程度减轻.行为异常、注意力不集中或学习困难患者中11例术后改善明显.头围增大和颞部局限性隆起就诊者术后头围及局部隆起无明显变化.影像学复查显示囊肿完全消失者46例(13.07%),囊肿部分消失者257例(73.01%),囊肿无明显变化者49例(13.92%).结论 中颅窝蛛网膜囊肿的临床特点为男性、左侧多发,年龄愈小手术效果越好,手术仅部分切除壁层即可;囊肿巨大时行分流手术效果好,分流管以中低压为佳.

Abstract：

Objective o investigate the clinical characteristics of middle cranial fossa arachnoid cyst (MCFAC) and its therapeutic effects with different surgical methods. Methods Three hundred and fifty-two patients with MCFAC (about 2.58% of patients with intracranial space occupying lesion),admitted to our hospital from May 2001 to May 2008, were chosen in out study; their clinical data,surgical approach and prognosis were analyzed retrospectively. The gender ratio of patient with MCFAC adopted resection of arachnoid cyst and arachnoid cyst-peritoneal shunt was performed in 28 patients.Results Follow-up was performed for 3 months to 3 years. The headache completely disappeared in 75 patients (58.59%) and partial remission in 41 (32.03%) after the operation. The frequency and degree of seizures obviously decreased in 8 of the patients with MCFIAC. Eleven patients with dystropy,attention-deficit disorder or difficulty of learning got improvement. The head circumference and local skull eminentia was stable. The cyst disappeared completely in 46 patients (13.07%), partially in 257 (73.01%) and no changes in 49 (13.92%). Conclusion The clinical features of MCFAC is that it mainly occur in the left side of male. The younger the patient with MCFAC is, the better the treatment effect in the surgical intervention is. good outcome can be achieved by resection of the parietal layer of arachnoid cysts. The indication of shunt with meso-low pressure shunt system is for larger arachnoid cyst.     

症状性颅内蛛网膜囊肿的临床治疗分析

目的 探讨症状性颅内蛛网膜囊肿(IAC)的手术治疗方法、适应证及其治疗效果.方法 回顾性分析南通大学附属医院神经外科自2000年1月至2010年1月收治的32例IAC患者临床资料,总结其手术方法及疗效. 结果 本组2例保守治疗的患者失随访.随访结束时,23例(72％)患者症状明显改善(囊肿体积缩小或临床症状缓解),6例(18％)患者症状无改变(临床症状和囊肿大小无改变),1例(3.1％)巨大鞍区-鞍上区IAC患者症状加重(临床症状恶化或囊肿增大);术后影像学检查显示囊肿消失4例(12.5％),囊肿缩小16例(50％),囊肿大小无改变12例(37.5％). 结论 IAC的主要手术适应证是颅内高压、确切的神经系统损害、脑组织压迫.显微外科手术以及神经内镜是治疗IAC的有效方法.     

Resection of an extensive thoracic arachnoid cyst via less-invasive targeted laminoplasties

Objective: Spinal arachnoid cysts are a known cause of spinal cord compression. When symptomatic, treatment of choice entails laminectomies over the length of the cyst in order to achieve complete cyst removal and fenestration.

Methods: A 60-year-old woman presented with a one-year history of progressive pain between the shoulder blades, exacerbated by sitting up or standing, and relieved by lying supine. MRI imaging revealed a T3–T7 dorsal intradural arachnoid cyst. Due to extant spinal deformity and medical comorbidity, the decision was made to proceed with selective laminoplasties at the superior and inferior limits of the cyst.

Results: After the dura was opened to reveal the margins, the cyst was sharply fenestrated and drained. Irrigation was passed through the cyst to ensure open communication, and a lumbar drain catheter was passed from the inferior to superior margin. The catheter was removed before closure. Postoperatively, MRI of the thoracic spine revealed decompression of the spinal cord and the patient noticed improvement in her symptoms. At 7-month follow-up, the patient remained free of symptoms and MRI demonstrated near-complete resolution of the cyst.

Conclusion: Although open exposure and complete resection are considered the treatment of choice for spinal arachnoid cysts, cyst fenestration through selective bony windows at the margins of the cyst represents a viable, less invasive alternative approach to effective cyst decompression, and can be considered in patients in whom a full exposure would be prohibitive.     

Arachnoid cysts of the middle cranial fossa: a clinical, radiological and follow-up study

Twenty-seven patients with CT-scan-diagnosed arachnoid cysts in the middle cranial fossa were studied. Five (18%) presented with progressive symptoms related to raised intracranial pressure which had developed after minor trauma and secondary bleeding, 12 (44%) presented with non-progressive symptoms, and 10 (37%) exhibited neurological syndromes not referable to the cyst. Among those with non-progressive symptoms, epilepsy was the most common presentation (67%). More than 60% of the cysts were small and limited to the anterior temporal region or to the Sylvian fissure, the remaining cysts involved both the anterior temporal region and the Sylvian fissure, and expanded to the adjacent fronto-temporal or fronto-parietal regions. The volume measurements of the brain tissue performed on CT scan revealed that between the volume of the two hemispheres there was no significant difference suggesting any evidence of agenesis or hypoplasia of the affected temporal lobe.     

Resolution of the large middle fossa arachnoid cyst without any identifiable cause: Case report

Although the possibility of spontaneous regression of intracranial arachnoid cysts (AC) during observational follow-up is widely recognized, the number of reports documenting such clinical course, often associated with the mild head trauma, is rather limited. We present a case of nearly complete resolution of the large middle fossa AC in a 5-year-old boy without any identifiable cause in 2.3 years after the initial diagnosis. It once again justifies observational strategy for AC not accompanying by mass effect and manifesting with minimal symptoms or diagnosed incidentally.     

Shunt-independent surgical treatment of middle cranial fossa arachnoid cysts in children

The best operative intervention for children with arachnoid cysts remains the subject of controversy. Recent reports stress that craniotomy for cyst fenestration is associated with a low incidence of morbidity and mortality and may leave the child shunt-independent. Among a total of 66 intracranial arachnoid cysts operated on in the authors’ department from 1985 to 1997, 44 cases (67%) were located in the middle cranial fossa. A higher incidence in the first decade of life (53 cases) and a marked male predominance (45 cases) were recognized. Headache, cranial deformities, symptoms of raised intracranial pressure, and seizures constituted the most frequent features of the clinical presentation. To determine which treatment provides the greatest benefit with the lowest incidence of complications, the records of the 44 patients with arachnoid cysts in the middle cranial fossa were reviewed. The mean age of these patients was 4.6 years (range 0–16 years). Different types of initial surgical procedures were performed. In 33 patients with middle cranial fossa arachnoid cysts (MCFAC) the initial surgery took the form of craniotomy with excision of the cyst walls and fenestration into the basal cisterns. Shunting procedures were performed in 9 patients: cysto-peritoneal shunts (CPS) were placed in 4 patients and ventriculo-peritoneal shunts (VPS), in 3 patients, and cyst excision was performed in addition to CPS in 2 patients. Excision of the cyst membrane alone without fenestration was performed in 2 patients. The initial treatment was successful in terms of reduced symptoms and decreased cyst size, with no additional treatment needed for the cyst, in 79% (26/33) of patients who had undergone excision of the cyst walls and fenestration into the basal cisterns, compared with 66% (6/9) of patients who had undergone shunting procedures. Cyst membrane excision was not successful in any of the patients who underwent this procedure alone. No significant difference in morbidity was noted between these different treatment options. On follow-up CT scan and MRI, cysts of types I and II (Galassi classification) exhibited a steady tendency to reduction or obliteration. These results confirm that radical excision of the outer and inner membranes of the cyst wall with fenestration into the basal cistern is a safe and effective shunt-independent procedure for MCFAC, especially for those of types I and II. Received: 28 May 1999 Revised: 10 August 1999     

蛛网膜囊肿55例外科治疗临床分析

目的 探讨蛛网膜囊肿的手术指征和手术方法.方法 回顾性分析收治的55例蛛网膜囊肿患者,其中行囊肿切除术12例,囊肿大部分切除 蛛网膜下腔疏通术27例,囊肿部分切除 脑池分流术4例,囊肿-腹腔分流术9例,3例未行手术治疗.结果 术后症状均有不同程度好转,3例未手术者因囊肿为非"责任"病灶而采取针对性治疗好转.结论 蛛网膜囊肿在明确"责任"病灶的前提下应积极手术治疗,囊肿-腹腔分流术可作为首选的治疗方法.     

Slit ventricle syndrome after cyst-peritoneal shunting for the treatment of intracranial arachnoid cyst

Serious complications following installation of a cyst-peritoneal shunt in an 8-year-old boy with asymptomatic arachnoid cyst in the middle cranial fossa are reported. Highly elevated intracranial pressure without association of ventriculomegaly seen in this patient indicates slit ventricle syndrome caused by malfunction of the cyst-peritoneal shunt. This phenomenon is worth recognizing as a possible consequence of cyst-peritoneal shunting for the treatment of intracranial arachnoid cyst.     

颅后窝蛛网膜囊肿的诊断及治疗（附36例分析）

目的探讨颅后窝蛛网膜囊肿（posterior fossa arachnoid cyst，PFAC）的诊断和治疗。方法回顾性分析36例颅后窝蛛网膜囊肿的临床资料。术前出现症状30例，无症状6例。单纯神经内镜手术24例，内镜控制下显微镜手术5例，单纯显微手术3例，未手术观察4例。结果30例术前出现症状病人中，术后症状消失13例，明显好转12例，无变化5例。32例病人术后随访3个月-5年。囊肿完全消失2例，不同程度缩小23例，无明显变化7例。结论CT或MR是诊断PFAC的有效方法，CT蛛网膜下腔-脑池造影（CTC）对区别真性囊肿与假性囊肿具有特异性。神经内镜手术是治疗颅后窝囊肿的有效、微创、并发症少的方法。     

Postnatal development and enlargement of primary middle cranial fossa arachnoid cyst recognized on repeat CT scans

The etiology and mechanism of expansion of primary intracranial arachnoid cysts have been much debated. A rare case of an 8-month-old boy is reported, in which postnatal development and enlargement of a middle cranial fossa arachnoid cyst was detected on follow-up CT scans. Based on intraoperative and histological findings, the cyst was found to be intra-arachnoid. The wall was excised completely, and the lobe adjacent to the cyst appeared normal apart from signs of atrophy. Histological study of the excised cyst revealed a common arachnoid membrane with neither ependymal nor inflammatory cells; the cyst fluid was similar to CSF. The etiology of the lesion remains unclear, but it was considered that the expansion of the cyst might have occurred through a ball-valve mechanism of the membrane in communication with the general subarachnoid space.     

Spontaneous disappearance of middle fossa arachnoid cyst after head injury

A case of middle fossa arachnoid cyst is presented, which disappeared after head injury. Five days after the trauma, CT scan revealed subdural fluid collection in addition to an arachnoid cyst in the middle fossa on the same side. As the subdural fluid resorbed, the cyst became smaller and disappeared on the follow-up CT scans without surgical intervention.