Slit ventricle syndrome after cyst-peritoneal shunting for temporal arachnoid cyst in children--a clinical entity difficult to detect on neuroimaging study

Slit ventricle syndrome, known to occur from malfunction of the shunt procedure for hydrocephalus, is reported after cyst-peritoneal shunt for temporal arachnoid cyst. Two children aged 12 and 10 years, who underwent cyst-peritoneal shunting for a large temporal arachnoid cyst at the age of 10 and 5 years, respectively, recently experienced several episodes of severe headache. Prior to admission, repeated CT scans did not reveal any morphological change in either of these two patients. Evidence of high intracranial pressure by lumbar tap revealed shunt malfunction. Both patients became free of neurological complaints and deficits after shunt revision. Despite elevated intracranial pressure due to shunt malfunction, neuroimaging studies showed no morphological changes in slit ventricle syndrome. Delay in both the diagnosis and prompt treatment may result in complete loss of visual acuity and even death. It is important to suspect this complication in patients with persistent elevated intracranial pressure symptoms and signs after any shunting procedure, regardless of unchanged neuroimaging studies. Once this is suspected, lumbar tap may be necessary and the choice of treatment is shunt revision.     

Posttraumatic intraventricular arachnoid cyst accompanied by pseudomeningoencephalocele in a child

Growing skull fracture (GSF) is a rare complication of head trauma. A posttraumatic intraventricular arachnoid cyst (AC), neither isolated nor accompanied by a GSF has not been reported previously. A seven-year-old girl was admitted after a severe head injury with a separated right parieto-occipital fracture and contusion. She responded well to conservative therapy. Seven weeks after discharge, she was re-admitted with a large parieto-occipital pseudomeningoencephalocele due to herniation of cerebrospinal fluid and neural tissue to the subgaleal space through the widened fracture defect, an extra-axial cyst at the posterior interhemispheric space and an intraventricular cystic mass. She underwent open surgery, and the intraventricular cystic mass was totally removed. The histological findings were consistent with an AC. One week after dural repair, hydrocephalus developed, and a ventriculo-peritoneal shunt was inserted. She did well during two-year follow-up. The present case is unique as an intraventricular AC following head trauma. When an intraventricular cystic lesion is encountered after severe head trauma, the possibility of an AC should be considered; especially with neighboring contused neural tissue and leptomeningeal cyst formation.     

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.     

Congenital arachnoid cyst of the lateral ventricles in children

The authors report a series of three children with symptomatic congenital arachnoid cyst of the lateral ventricles. Presenting symptoms consisted of macrocephally, delay in psychomotor development, and seizures. CT findings were of a well-defined cystic lesion placed in the atrium of the lateral ventricle. One child was treated by direct cyst exposure and cysto-peritoneal shunt. The other two were treated with ventriculo-cystoperitoneal shunts; in one of these, we used a ventriculoscope both for cyst fenestration and for accurate shunt placement. The origin of intraventricular arachnoid cysts seems to be secondary to the displacement of arachnoid cells by the vascular mesenchyma, through the choroid fissure, during the process of choroid plexus development.     

Postinflammatory arachnoid cyst of the quadrigeminal cistern

Arachnoid cysts of the quadrigeminal cistern are rare. Patients with this lesion are usually normal at birth, and signs of increased intracranial pressure (IICP) develop at about 4 to 12 months of age. However, there has been no report about this mechanism. A case of arachnoid cyst of the quadrigeminal cistern is presented. In this case, the process of the cyst growth was observed during the course of follow-up for shunted hydrocephalus. Symptoms coincided with the growth of the cyst. Therefore, the development of the clinical symptoms was thought to be due to IICP caused by cyst expansion. Our case was complicated by inflammation, something that may offer a key to solving the mechanism of cyst fluid accumulation and the relationship between symptoms and development of the cyst.     

Endoscopic approach to arachnoid cyst

A prospective study of 36 consecutive patients with congenital arachnoid cysts treated endoscopically is reported. There were 15 female and 21 male patients. The mean age at the time of diagnosis was 12.3 years (10 days to 38 years). Arachnoid cysts were located in the suprasellar region in 16 patients, the sylvian fissure in 11, the quadrigeminal cistern in 4 and the posterior fossa in 5. Endoscopic fenestration was combined with cysto-peritoneal shunting for 6 temporal cysts and with ventriculo-peritoneal shunting in 1 suprasellar cyst. Mean postoperative follow-up was 4.2 years (range 1–8 years). Follow-up imaging studies showed that 28 arachnoid cysts (77.8%) were obliterated after endoscopic procedures. Long-term clinical results were good in all patients, although the cysts of 8 patients were not reduced in size. There was no mortality or morbidity. We conclude that endoscopic procedures may be a promising alternative to microsurgical operations or shunting for the treatment of arachnoid cysts. Received: 30 December 1998     

A case of hypothalamic hamartoma associated with arachnoid cyst

A 14-year-old girl presented with seizures. Radiological examinations revealed an arachnoid cyst in left middle fossa and a cystic mass in the interpeduncular cistern. The cyst was opened and the wall of the cyst and a mass were biopsied. The histological findings were characteristic of an arachnoid cyst and hamartoma, respectively. A hypothalamic hamartoma associated with an arachnoid cyst is comparatively rare; however, such a case may help clarify the genesis of this malformation. Received: 5 November 1998 Accepted: 19 January 1999     

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.     

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     

颅内蛛网膜囊肿-腹腔分流术后分流管依赖二例并文献复习

目的 探讨颅内蛛网膜囊肿-腹腔分流术后并发分流管依赖的可能机制、影像学特征及治疗方法.方法 分析2例蛛网膜囊肿行囊肿-腹腔分流术后并发分流管依赖的诊治过程,并结合文献进行讨论和总结.结果 2例均表现为分流管功能丧失后继发严重颅高压症状,其中1例行侧脑室-腹腔分流术;另1例先行囊肿-腹腔分流术,1个月后分流管堵塞,改行腰大池-腹腔分流术.经治疗后2例均痊愈出院,预后良好.结论 分流管依赖是继发于分流管功能下降或丧失,临床表现呈持续进展性颅内压增高;影像学上可观察到侧脑室正常或轻度缩小,原囊肿短期内可复现增大;解除分流管梗阻或重新建立脑脊液引流渠道是安全有效的治疗方法.     

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.     

Intracranial arachnoid cysts: current concepts and treatment alternatives

Arachnoid cysts are non-tumorous intra-arachnoid fluid collections that account for about 1% of all intracranial space-occupying lesions. In this article, we review the current concepts about these lesions and discuss the treatment alternatives. The aetiology of arachnoid cysts has been a controversial subject. They are regarded as developmental abnormality of the arachnoid, originating from a splitting or duplication of this membrane. The establishment of a single CSF space, by surgically communicating the cyst with the ventricular system or basal cisterns, appears to offer the best chance of a success in the treatment of arachnoid cysts. Long-term prognosis for patients with arachnoid cysts and well-preserved neurological conditions is good, even in the case of subtotal excision. Clinical follow-up and MRI allow earlier diagnosis of recurrence.     

Familial posterior fossa arachnoid cyst

Background Arachnoid cysts are a relatively common incidental finding on CT scans of the brain. They most commonly occur in the middle cranial fossa, where familial occurrence has rarely been reported. Posterior fossa arachnoid cysts are more unusual.Case histories We report the presence of quadrigeminal cistern arachnoid cysts in siblings.     

Huge arachnoid cyst incorporating choroid plexus

Background We report a rare case of arachnoid cyst incorporating choroid plexus. This 7-month-old girl presented with macrocrania. Magnetic resonance (MR) imaging disclosed a cystic lesion arising from the left prepontine cistern extending to the left middle cranial fossa.Methods First, we performed resection of the membrane microscopically and obtained an adequate reduction of the cystic size. However, 4 months after the first operation, the cyst was enlarged again, and bulging of the portion of the craniotomy was noted. Thus, we performed neuroendoscopic transcortical ventriculo-cyst-cysternostomy and confirmed the choroid plexus inside of the arachnoid cyst.Discussion Postoperative course was uneventful. This is the first reported case of choroid plexus within an arachnoid cyst, determined neuroendoscopically.     

颅内蛛网膜囊肿伴发癫痫的手术治疗

目的 通过对37例颅内蛛网膜囊肿(intracranial arachnoid cyst,IAC)伴发癫痫患者手术治疗情况的回顾分析,以期对此类患者手术方法的选择提供依据.方法 25例患者归为囊肿手术组,方法有囊肿壁切除术、囊肿-腹腔分流术和囊肿造瘘术;12例患者归为癫痫手术组,行囊肿壁切除术同时,切除囊肿周围萎缩变性致痫脑组织,如果患者残存颞叶内侧及杏仁核、海马结构,也予以切除,如囊肿周围邻近功能区,则通过体感诱发电位确定中央沟后于功能区行多处软膜下横切术,必要时行脑皮质离断术和胼胝体切开术,12例均行术中皮层脑电图监测.结果 术后37例患者中6例囊肿消失,17例减小,14例无变化,两组相比无显著性差异;囊肿手术组2例无发作,8例改善,15例无效,手术总有效率40%;癫痫手术组7例无发作,3例改善,2例无效,手术总有效率83.3%,两组相比有显著性差异(P＜0.05).结论 IAC伴发癫痫患者术前进行癫痫灶的确认,术中行囊肿壁切除术同时切除癫痫灶,大大提高IAC伴发癫痫的手术疗效.     

Neonatal anterior cervical arachnoid cyst: case report and review of the literature

OBJECTIVE: Anterior cervical arachnoid cysts are rare in the pediatric population, with only 16 cases reported. We present the first case of an anterior cervical arachnoid cyst in a neonate and review the literature on pediatric cervical arachnoid cysts. CLINICAL PRESENTATION: A 16-day-old baby girl with a history of myelomeningocele repair progressively developed symptoms of upper extremity weakness over the course of 2 weeks. Magnetic resonance imaging (MRI) demonstrated a compressive arachnoid cyst extending from C2 to C7. INTERVENTION: The child was taken for posterior cervical laminoplasty and cyst fenestration. Intraoperatively, diffuse cervical arachnoiditis was noted. Rapid improvement in upper extremity paresis was noted within 24 h of surgery, and MRI confirmed decompression of the cyst. However, flaccid upper extremity paresis recurred within 2 weeks. MRI confirmed recurrence of the anterior cervical arachnoid cyst. The child was taken for a secondary fenestration and stenting of the cyst. Only partial improvement in arm function was noted by 1 month following reoperation. CONCLUSION: Arachnoid cysts can be effectively treated with surgical fenestration, shunting, and complete or partial excision. Rapid identification and treatment results in improvement in myelopathic symptoms; however, the most efficacious treatment modality remains unknown. Of the 17 cases of anterior cervical arachnoid cysts reported in the literature, 11 (65%) have had either prior myelomeningocele repair or a history of spinal trauma. Anterior cervical arachnoid cysts should be considered in the differential diagnosis of acute onset myelopathy in the pediatric population especially in cases with a history of spinal trauma or myelomeningocele repair.     

Arachnoid cyst of the collicular cistern

Arachnoid cysts of the collicular cistern are rare. Two patients with this lesion are reported in whom the extent and location of the cyst were shown by computed tomography. The clinical and radiographic features of this lesion are summarized.     

Magnetic resonance diagnosis of spinal arachnoid cyst

Magnetic resonance (MR) findings in one case each of extradural and intradural arachnoid cyst are described. Thoracic segments were involved in both cases. The cysts were slightly more intense than cerebrospinal fluid in both cases on T1 weighted images. The nature and extent of the lesions wer better demonstrated on MR images as compared with combined myelography and computed tomography.