Intracranial arachnoid cysts in children: related signs and associated anomalies

Arachnoid cyst in the pediatric patient: What the radiologist needs to know

Arachnoid cysts are the most common incidentally discovered intracranial lesions on imaging and the most common cystic intracranial lesions. They may be developmental or secondary. A relative lack of recent literature and any comprehensive radiological review on arachnoid cysts has led to a general lack of awareness among radiologists of symptomatic or complicated arachnoid cysts. This is particularly concerning in pediatric patients. While arachnoid cysts are asymptomatic in most cases, they can cause clinical symptoms in a minority of cases, especially when they occur in unusual sites. These include intraventricular locations where they may cause hydrocephalus, the basal cisterns where they may compress cranial nerves, the cerebellopontine angle where they have to be differentiated from a number of cystic lesions, the cavum septum pellucidum or cavum velum interpositum, the choroid fissure where they can entrap the temporal horn and compress the hippocampus, the posterior fossa where they need to be differentiated from other posterior fossa cystic lesions, and within the spinal canal where there is a concern for cord or nerve root compression. Larger cysts are more prone to complications such as mass effect, hemorrhage, and rupture. Hemorrhage and rupture often present with acute symptoms. Ruptured cysts lose their characteristic imaging appearance and can mimic several ominous pathologies. It therefore becomes vital to accurately diagnose these cases as complications of pre-existing arachnoid cysts for appropriate management. A detailed review of all diagnostic imaging aspects of arachnoid cysts will help fill in the existing information void on this important entity.

Cochlear Implant in a Child with a Large Arachnoid Cyst and Cysto-peritoneal Shunt

Profound hearing loss requiring cochlear implantation and arachnoid cyst requiring placement of Cysto-Peritoneal Shunt (CPS) are two commonly seen entities. However, there are very few published cases of patients requiring both of them. The present report describes the importance of multidisciplinary surgical planning in one such patient.

Surgical treatment and clinical outcome of large pediatric interhemispheric cysts with callosal agenesis: A systematic literature review with four additional patients

OBJECTIVE

Large interhemispheric cysts (IHC) with partial or complete agenesis of corpus callosum (ACC) constitute a heterogeneous group of rare disorders. Neurosurgical treatment, in the terms of if, when and how to operate, remains unclear METHODS: We performed a surgical literature review of series or reports of IHCs with callosal anomalies; we evaluated whether revision surgeries were necessary and considered the dimensional change in the cyst postoperatively and the developmental outcome. We also reported our experience with sfour patients treated by programmable cysto-peritoneal (CP) shunting. Patients' clinical history, neuroradiological and neuropsychological performances were evaluated pre and post operatively.

RESULTS

The review included 133 patients with surgically-treated IHCs. Although most authors are in agreement to perform surgery if the patients present signs of raised ICP and to not intervene in those completely asymptomatic, for other signs and symptoms the debate is still open; only few authors performed cognitive tests pre and post-operatively. Shunting procedures were successful in 60% of our reviewed cases and often lead to a major cyst collapse. Craniotomy achieves good results but is extremely invasive. Endoscopy is minimally invasive and our review demonstrated a success rate of 66%. However, endoscopy does not ensue a complete cyst collapse. Our series and review seem to suggest a possible link between parenchymal re-expansion and cognitive outcome.

CONCLUSIONS

Early and effective surgery seems to obtain a greater cerebral parenchyma re-expansion and long-term cognitive evolution. Endoscopy is safe and reliable, but more data is needed on the impact of uncomplete cyst collapse on neurocognitive outcome.

Long-term Follow-up of a Multiloculated Arachnoid Cyst of the Middle Cranial Fossa

Arachnoid cysts are benign intracranial lesions that are typically diagnosed incidentally. We describe the case of a 56-year-old man who presented with a multiloculated arachnoid cyst of the middle cranial fossa that extended into the sphenoid sinus. The lesion was identified on computed tomography of the head, which had been obtained for an unrelated investigation. However, establishing a definitive diagnosis proved to be difficult. Because the cyst had caused extensive skull base erosion, the patient was managed conservatively with close observation. We report the radiographic progression of this lesion during more than a decade of follow-up, and we review the literature pertaining to the presentation, pathophysiology, and treatment of arachnoid cysts.

Intracranial extradural arachnoid cyst in a child

INTRODUCTION

Arachnoid cysts are benign developmental anomalies of arachnoid membrane origin that can occur anywhere along the neuro-axis. They are believed to develop from the splitting or duplication of the arachnoid membrane by CSF that is trapped by a ball-valve mechanism. Intracranial arachnoid cysts have only been described as intradural lesions while spinal arachnoid cysts can be both intradural or extradural.

CASE REPORT

After an extensive literature review, we report the first case of an intracranial, extradural arachnoid cyst in a 5-yearold girl. The child presented with a 2-week history of suspected seizure-like activity and imaging revealed a large midline extradural CSF-containing arachnoid cyst causing severe compression of the superior sagittal sinus and underlying brain. Venous flow through the sagittal sinus was nearly obliterated. Osseous changes and bone growth adjacent to the cyst was also noted on imaging and intraoperatively. She underwent a bifrontal craniotomy and cyst excision with decompression of underlying brain and reestablishment of venous flow through the sagittal sinus.

[Imaging diagnosis of arachnoid cysts]

Arachnoid cysts are malformed lesions that contain a fluid similar to the cerebrospinal fluid, and are usually located within the arachnoidal membrane. They represent 1% of all intracranial lesions, and in recent years, with the development of radiological techniques, the clinical detectability of arachnoid cysts seems to have increased. Although the majority of diagnosed arachnoid cysts are located in the cranial cavity and especially in the Sylvian fissure, a small number are located at spinal level and they can occur extra- or intra-spinally. An analysis is carried out, detailing the various tests used for the diagnosis of both intracranial and spinal arachnoids cysts, analysing the indications of each one depending on the location of the cysts and patient age.

[Epidemiology and classification of arachnoid cysts in children]

The prevalence of arachnoid cysts in children is 1-3%. They are more frequent in boys. They can be located intracranially or in the spine. Intracranial cysts are classified as supratentorial, infratentorial, and supra-infratentorial (tentorial notch). Supratentorial are divided into middle cranial fossa, convexity, inter-hemisferic, sellar region, and intraventricular. Infratentorial are classified into supracerebellar, infracerebellar, hemispheric, clivus, and cerebellopontine angle. Finally spinal arachnoid cysts are classified taking into account whether they are extra- or intradural, and nerve root involvement.

Intracranial arachnoid cyst on dental radiography: a diagnostic challenge

Intracranial arachnoid cysts (IACs) can present as congenital asymptomatic lesions that may predispose them to present as an incidental finding during radiographic examination. On the other hand, IACs may also give rise to a series of neurologic symptoms depending on their size and location, such as vomiting, seizures, headache, and ataxia. Skull deformities, including macrocephaly, may occur and become remarkable on dental radiology. We report 2 patients who were identified with IAC before orthodontic treatment. The dental radiologic appearance of IAC is discussed and may constitute a diagnostic challenge to both the dentist and radiologist.

Language impairment associated with arachnoid cysts: recovery after surgical treatment

Supporting data from the literature, we observe that large arachnoid cysts may affect cognitive function. Neuropsychologic assessment plus magnetic resonance imaging allowed for documentation of associations between left temporal arachnoid cysts, language impairment, and other cognitive dysfunctions. Significant cognitive improvements were evident soon after cysto-peritoneal shunting. These observations reinforce the rationale for neuropsychologic assessments of patients with developmental delay and arachnoid cysts, and support the potential benefit of surgical decompression for arachnoid cysts associated with neurologic deficits, even if surgery is performed well after the occurrence of neurologic deficits.

The endocrine spectrum of intracranial cysts in childhood and review of the literature

Intracranial cysts (ICC) may cause a wide spectrum of endocrinological disorders. We evaluated 27 patients who were diagnosed with ICC during investigation for neuroendocrine dysfunctions and reviewed the relevant literature. The types of ICC in the patients were arachnoid cysts (n = 13); Rathke cleft cysts (n = 7); pineal cysts (n = 5); an ependymal cyst (n = 1) and a cavum septum pellucidum cyst (n = 1). The neuroendocrine dysfunctions of the patients were obesity (n = 7), isolated growth hormone deficiency (n = 6), central precocious puberty (n = 6), multiple pituitary hormone deficiency (n = 3), central diabetes insipidus (n = 1), growth hormone deficiency and central precocious puberty (n = 1), obesity and galactorrhea (n = 1), obesity and hypogonadotropic hypogonadism (n = 1) and growth hormone neurosecretory dysfunction (n = 1). Only three patients, who had arachnoid cysts, showed neurologic symptomatology. Although three patients underwent surgery, no improvements in endocrinological dysfunctions were observed. ICC should be considered when evaluating patients with endocrinological problems and patients with coincidental ICC should be recommended for follow-up.

Single-voxel magnetic resonance spectroscopy of brain tissue adjacent to arachnoid cysts of epileptic patients

Intracranial arachnoid cysts (ACs) are usually asymptomatic, benign developmental anomalies. The most frequent clinical manifestations are cranial expansion, hydrocephaly, headache, epileptic seizures, psychomotor retardation, and aphasia. It is unknown whether there is a correlation between intracranial AC and epileptic seizures without obvious intracranial pressure signs. In vivo magnetic resonance spectroscopy is a technique used for the noninvasive investigation of the various metabolites of cerebral biochemical reactions. Magnetic resonance spectroscopy is also being used increasingly commonly in epileptogenic situations as a noninvasive technique. The purpose of this study was to evaluate the proton magnetic resonance spectroscopic pattern of the contents of tissue adjacent to AC and to determine whether there are any characteristic spectral patterns that may be helpful in evaluating whether these lesions are epileptogenic foci. In conclusion, although the number of cases was limited, this finding may be seen as indicating that there is no association between AC and epilepsy.

Sylvian fissure arachnoid cysts: a survey on their diagnostic workout and practical management

BACKGROUND

The management of Sylvian arachnoid cysts in children is still a matter of debate. Diagnosis is often incidental, and symptoms are frequently aspecific in symptomatic cases. Suggested diagnostic investigation results have been often unclear. Surgical treatment is also controversial, pure, and assisted endoscopic cyst marsupialization having entered in the traditional debate between craniotomic and shunting approach

PURPOSE

The objective of the present study was to survey if (and, eventually, which) agreement points do actually exist between internationally recognized pediatric neurosurgery centers in the management of children with a controversial type of Sylvian arachnoid cyst (Type II cyst).

METHODS

Contributors were asked to answer to a six-separate-part multiple choice questionnaire related to the case of a 2.7-year-old boy with a Type II left Sylvian arachnoid cyst presented in different clinical situations. If surgery was indicated, it was asked which surgical procedure the authors would have suggested as first option.

RESULTS AND CONCLUSIONS

The option of the mere clinical observation was chosen by the majority of surgeons in case of asymptomatic clinical discovery. On the other hand, a constantly high percentage of participants suggested direct surgical treatment based on clinical manifestations or as a preventive measure justified by the risk of spontaneous or traumatic intracranial bleeding. The only diagnostic investigation result which significantly influenced the surgical indication was a localizing electroencephalography, if the child presented with seizures. The result is that in most cases the surgical indication was based on aspecific clinical manifestations and laboratory data. Craniotomy and arachnoid cyst marsupialization represented the preferred surgical option (66.6%), 28.8% of the participants suggesting pure or assisted endoscopic cyst marsupialization as primary surgical procedure. Cyst shunting was suggested by only three centers.

Management of a suprasellar arachnoid cyst identified using prenatal sonography

We present a rare case of suprasellar arachnoid cyst discovered incidentally on routine fetal sonographic examination. Serial sonographic and MRI scanning led to a prenatal diagnosis and appropriate endoscopic treatment at 5 months of age. The patient is currently developing normally at 3 years of age. Careful screening of fetal intracranial abnormalities is important in routine prenatal sonographic examination for early intervention, which will prevent irreversible complications such as endocrine disorders and visual impairment.

Helmetlike skull deformity with a large arachnoid cyst

BACKGROUND

It is not difficult to find localized skull ballooning or macrocrania in patients with intracranial arachnoid cysts. However, there have been no previous reports regarding large localized skull protuberant deformities resembling a war helmet. The authors report with a review of literature a case of an adult with helmetlike skull deformity resulting from a large supratentorial arachnoid cyst.

CASE DESCRIPTION

A 35-year-old man presented with a large head deformity since his early childhood that had been the result of gradual progression from infantile macrocrania. He also had mental retardation, sixth cranial nerve palsy with recent aggravation of headache, reduced activity, poor voiding control, and walking disturbance. Magnetic resonance imaging of the head showed hydrocephalus with a large supratentorial arachnoid cyst located in the bilateral parietooccipital area compressing the hemisphere anteriorly, and the tentorium and cerebellum inferiorly. Magnetic resonance venogram demonstrated low-lying short transverse and lateral sinuses, and the superior sagittal sinus and falx were displaced to the right side. Radioisotopic cisternogram showed nonfilling of the isotope in the bilateral parietooccipital area. Cerebrospinal fluid pressure measured by lumbar puncture was 17 cm H(2)O. We tentatively diagnosed the condition as normopressure hydrocephalus with a large supratentorial arachnoid cyst. His headache, reduced activity, poor voiding control, and walking disturbance improved after a cystoperitoneal shunt.

CONCLUSIONS

This might suggest that large arachnoid cysts found in childhood should be treated for prevention of skull deformity and late aggravation of increased intracranial pressure.

Hippocampal dysgenesis associated with temporal lobe hypoplasia and arachnoid cyst of the middle cranial fossa

We describe two children with left hippocampal dysgenesis in association with temporal lobe hypoplasia and arachnoid cyst of the middle cranial fossa. The hippocampus showed an abnormal globular shape and blurred internal structure in both patients. One of the patients had juvenile myoclonic epilepsy without evidence of seizure onset in the abnormal temporal region. The other patient did not have epilepsy; however, he showed developmental language disorder with a probable relationship to the left temporal abnormalities.

22q13 deletion syndrome: an update and review for the primary pediatrician

Recent advances in genetic testing can help to provide a specific diagnosis to children born with syndromes that result in congenital anomalies and developmental delay. One such emerging condition is the 22q13 deletion syndrome. With the introduction of subtelomeric fluorescence-in-situ hybridization (FISH) analysis, the 22q13 deletion has become recognized as a relatively widespread and underdiagnosed cause of mental retardation. Primary-care physicians play an important role in the care of children with 22q13 deletion syndrome, from suspecting the diagnosis in a developmentally delayed child through the medical, developmental, and behavioral aspects of their care. Furthermore, they serve as a valuable source of support and advocacy for the family and a resource for other care providers. The remainder of this article addresses the current state of knowledge regarding 22q13 deletion syndrome and offers the primary-care physician a framework in which to provide care and information.

Microsurgical Keyhole Approach for Middle Fossa Arachnoid Cyst Fenestration

OBJECTIVE

The optimal surgical treatment for symptomatic temporal arachnoid cysts is controversial. Therapeutic options include cyst shunting, endoscopic fenestration, and craniotomy for fenestration. We reviewed the results for patients who were treated primarily with craniotomy and fenestration at our institution, to provide a baseline for comparisons of the efficacies of other treatment modalities.

METHODS

A retrospective review of data for 50 children who underwent keyhole craniotomy for fenestration of temporal arachnoid cysts between 1994 and 2001 was performed after institutional review board approval. During that period, the first-line treatment for all symptomatic middle fossa arachnoid cysts was microcraniotomy for fenestration. Microsurgical dissection to create communications between the cyst cavity and basal cisterns was the goal. All patient records were reviewed and numerous variables related to presentation, cyst size and classification, treatment, cyst resolution, symptom resolution, follow-up periods, and cyst outcomes were recorded.

RESULTS

Fifty temporal arachnoid cysts in 50 treated patients were identified. The average age at the time of surgery was 68 ± 57.2 months. The follow-up periods averaged 36 months. There were 34 male and 16 female patients in the series. Twenty-six cysts were on the left side. Indications for surgery included intractable headaches (45%), increasing cyst size (21%), seizures (25%), and hemiparesis (8%). The symptoms most likely to improve were hemiparesis (100%) and abducens nerve palsies. Headaches (67%) and seizure disorders (50%) were less likely to improve. Nine patients exhibited progressive increases in cyst size in serial imaging studies. Those patients were monitored for a mean of 40 ± 23 months before intervention. In the entire series, 82% of patients demonstrated decreases in cyst size in serial imaging studies. Of those patients, 18% demonstrated complete cyst effacement. Overall, 83% of patients with Grade II cysts and 75% of patients with Grade III cysts exhibited evidence of decreases in cyst size in long-term monitoring. Two patients required shunting after craniotomy (4%). Hospital stays averaged 3.4 days. Total surgical times averaged 115 minutes. No significant blood loss occurred (5–50 ml). Complications included spontaneously resolving pseudomeningocele (10%), transient Cranial Nerve III palsy (6%), cerebrospinal fluid leak (6%), subdural hematoma (4%), and wound infection (2%).

CONCLUSION

A microsurgical keyhole approach to arachnoid cyst fenestration is a safe effective method for treating middle fossa cysts. This procedure can be performed with minimal morbidity via a minicraniotomy. Compared with an endoscopic approach, better control of hemostasis can be obtained, because of the ability to use bipolar forceps and other standard instruments. The operative time and length of hospital stay were not excessively increased.

Quadrigeminal cisterna arachnoid cyst diagnosed by MRI in five dogs

Arachnoid cysts of the quadrigeminal cisterna are infratentorial cystic lesions located between the collicular plate and the incisural notch of the tentorium. We report here five cases of quadrigeminal cisterna arachnoid cysts in dogs. In this study, four of the five dogs were male, three showed signs of seizures, and one dog was over 10 years of age. In two of the dogs, cysts were discovered incidentally. In previous reports, most intracranial arachnoid cysts were located in the quadrigeminal cisterna. The presence of cysts should be considered in toy breeds presenting for seizures or ataxia.

Intracranial arachnoid cysts in children: a review of pathogenesis, clinical features, and management

Arachnoid cysts are developmental anomalies that are most often diagnosed in childhood. They are often discovered as incidental findings found on imaging. Occasionally they may produce symptoms because of expansion or bleeding. There may be underlying maldevelopment of the cortex especially the temporal lobe. There is controversy regarding the role and the type of surgery indicated in its treatment. Recent descriptions of aphasia and attention-deficit disorders associated with these cysts indicate that we do not fully understand this entity. There is also no acceptable explanation for the male preponderance and increased incidence on the left side. The distribution, clinical features, treatment modalities, and some unusual syndromes associated with arachnoid cysts in children are discussed in this review.