Prevalence and natural history of arachnoid cysts in children

Optic Nerve Edema in Pediatric Middle Cranial Fossa Arachnoid Cysts: Report of 51 Patients From a Single Institution

BACKGROUND

Middle fossa arachnoid cysts (MFACs) are rare, congenital lesions that may rupture and cause symptoms of elevated intracranial pressure. We sought to describe the presence of and factors associated with optic nerve edema in MFACs, focusing on the utility of ophthalmologic evaluations for guiding cyst management.

METHODS

We reviewed clinical and radiographic information for all patients with MFACs with ophthalmologic evaluations at our institution. Headache, cranial nerve palsy, emesis, altered mental status, fatigue, and seizures were considered MFAC-related symptoms. Univariate and multivariable analyses evaluated factors associated with optic edema.

RESULTS

Fifty-one patients between 2003 and 2022 were included. Cysts were a median volume of 169.9 cm3 (interquartile range: 70.5, 647.7). Evidence of rupture with subdural hematoma/hygroma occurred in 19 (37.3%) patients. Eighteen (35.3%) patients underwent surgery for their cyst and/or rupture-associated intracranial bleed. Eleven (21.6%) patients had optic edema; all were symptomatic and experienced cyst rupture. Ten of these patients received surgery. Postoperatively, optic edema resolved in 80% of cases. Cyst volume and symptoms were not associated with optic edema; however, patients with ruptured cysts, particularly those with traumatic rupture, were more likely to have optic edema and receive surgery (P < 0.001).

CONCLUSIONS

We found optic edema in 21.6% of evaluated MFACs, and this comprised of 57.9% of ruptured cases. Optic edema was not found in unruptured cysts. Cyst fenestration improved optic edema and patient symptoms. In conjunction with clinical history and neuroimaging, optic edema may help guide MFAC management, particularly in patients with cyst rupture.

Long term clinical and radiological outcomes following surgical treatment of symptomatic cranial arachnoid cyst: A population based consecutive cohort study

OBJECTIVE

Symptomatic intracranial arachnoid cysts are treated mainly through surgical resection, endoscopic fenestration, or by implanting cystoperitoneal (CP) shunt. However, the use of a specific technique remains controversial. The purpose of this study is to discuss these surgical modalities in symptomatic patients with intracranial arachnoid cysts (ACs) and investigate which has better outcomes and less complications by comparing variable preoperative and postoperative parameters.

METHODS

An analysis of thirty-nine symptomatic patients who underwent intracranial arachnoid cyst surgery in the department of neurosurgery between 2009 and 2023 was performed. Patients were retrospectively compared based on age group, gender, anatomical location, laterality, type of intervention, clinical and volumetric changes, postoperative complications and outcome.

RESULTS

Of the 39 patients, 20 patients (51.28 %) received CP shunt. Eleven patients (28.2 %) underwent endoscopic fenestration, and 8 patients (20.5 %) had surgical resection. The age at the time of first operation ranged from 1 month to 59.9 years (mean age: 16.8 years), and the pediatric patients were 25 (64.1 %). The most common initial symptom was headache which was observed in 19 patients (48.7 %), followed by seizure in 12 patients (30.8 %), vomiting in 11 patients (28.2 %), visual dysfunction in 8 patients (20.5 %), drowsiness in 8 patients (20.5 %), visual symptoms in 8 patients (20.5 %), cognitive impairment in 4 patients (10.3 %), focal neurological deficits in 3 patients (7.7 %), and cranial nerve involvement in 1 patient (2.6 %). 24 patients (61.5 %) showed improvement while in 15 patients (38.5 %) the symptoms persisted or worsened. Postoperatively, patients were followed up for an average of one year. The highest improvement rate was noted in endoscopic fenestration with 9 improved patients (81.8 %), followed by surgical resection with 5 symptom-free patients (62.5 %). The worst outcomes were seen in cystoperitoneal shunt with only half of the patients were relieved (50 %). Complications developed in 2 patients (25 %) who underwent surgical resection, 5 patients (45.5 %) who had endoscopic fenestration, and 13 patients (65 %) who had cystoperitoneal shunting.

CONCLUSION

Endoscopic fenestration has the highest improvement rate, the lowest serious complications along with being the least invasive technique. These features make it the optimal modality in treatment of ACs. Surgical resection or cystoperitoneal shunt can be considered as secondary techniques when patients report unchanged or worsening symptoms.

Staged neurosurgical approach for giant and progressive neonatal arachnoid cysts: a case series and review of the literature

OBJECTIVES

Prenatally diagnosed complex arachnoid cysts are very rare. While the true prenatal incidence is still unknown, they account for approximately 1% of intracranial masses in newborns. They rarely exhibit rapid growth or cause obstructive hydrocephalus, but if they increase to such a dimension during pregnancy, the ideal management is not well established. We present our detailed perinatal experience, covering prenatal diagnosis, a compassionate delivery process, and neonatal stabilization. Finally, a thorough postnatal neurosurgical intervention was performed. Initially, our focus was on the gradual reduction of cyst size as a primary effort, followed by subsequent definitive surgical treatment.

METHODS

This case series shows the treatment course of three fetuses with antenatally diagnosed large arachnoid cysts. We present pre- and postnatal management and imaging, as well as the surgical treatment plan and the available clinical course during follow-up.

RESULTS

Two girls and one boy were included in the current review. All three cases presented with prenatally diagnosed complex arachnoid cysts that increased in size during pregnancy. The mean gestational age at delivery was 35 weeks (range 32 to 37 weeks), and all patients were delivered by a caesarian section. Increasing head circumference and compression of brain structures were indications for delivery, as they are associated with a high risk of excess intracranial pressures and CSF diapedesis, as well as traumatic delivery and maternal complications. All cysts were supratentorial in location; one expanded into the posterior fossa, and one was a multicompartment cyst. All children underwent an initial surgical procedure within the first days of life. To relieve cyst pressure and achieve a reduction in head circumference, an ultrasound-guided or endoscopic-assisted internal shunt with drainage of the cyst to the ventricles or subdural/subarachnoid space was inserted. Definite surgical therapy consisted of cyst marsupialization and/or cysto-peritoneal shunt implantation. All children survived without severe neurodevelopmental impairments.

CONCLUSION

With the cases presented, we demonstrate that the slow reduction of immense cyst size as an initial procedure until optimal requirements for final surgical treatment were achieved has proven to be optimal for neurological outcome. Special emphasis has to be taken on the delicate nature of premature newborn babies, and surgical steps have to be thoroughly considered within the interdisciplinary team.

Cognition in children with arachnoid cysts - A five-year follow-up after microneurosurgical fenestration

BACKGROUND AND PURPOSE

In recent years there has been a re-evaluation regarding the clinical implications of temporal lobe arachnoid cysts (temporal arachnoid cysts) in children. These cysts have often been considered asymptomatic, or if symptomatic, only causing focal neurological symptoms or signs of increased intracranial pressure. However, several studies have more recently reported on cognitive symptoms improving after surgery. This study aimed to evaluate if reported cognitive improvement after surgery of temporal arachnoid cysts were stable after five years.

METHOD

Ten consecutive children (m = 14.65; range 12.1-19.415 were assessed cognitively five years after micro-neurosurgical fenestration of a temporal arachnoid cyst. Results were compared to results from their pre- and post-surgical evaluations. Evaluations included the Wechsler-scales, Boston Naming Test (BNT), Rey Auditory Verbal Learning Test (RAVLT), verbal fluency test (FAS) and Rey Complex Figure Test (RCFT).

RESULTS

The analysis revealed significant postsurgical improvement compared to baseline on the Wechsler-scales measures of general intelligence (FSIQ), verbal abilities (VCI) and processing speed (PSI). Mean differences after surgery were 8.3 for FSIQ, (p = 0.026), 8.5 for VI (p =  < .01) and 9.9 for PSI (p = 0.03). There were no significant differences in mean test results when comparing postsurgical scores with scores five years after surgery, indicating long-term stability of improvements.

CONCLUSION

The results indicate that affected cognitive functions in children with temporal arachnoid cysts improve after surgery and that the improvements remain stable five years later. The improvements and long term stability were also consistent with the experience of both parents and children. The findings provide a strong argument for neurosurgical fenestration of temporal arachnoid cysts in children.

Spontaneous regression of an interhemispheric arachnoid cyst: illustrative case

BACKGROUND

Intracranial arachnoid cysts are benign collections of cerebrospinal fluid that are often asymptomatic and discovered incidentally. An interhemispheric location of these lesions is rare, with only a few such cases reported in the literature. Though spontaneous regression of arachnoid cysts has been described in other locations, to date this phenomenon has not been reported in interhemispheric fissure cysts.

OBSERVATIONS

In this report, we describe a patient with a large, multiloculated interhemispheric arachnoid cyst diagnosed on prenatal ultrasound. She did not exhibit neurologic deficits or signs of increased intracranial pressure and was observed with serial imaging. After several years of observation, imaging revealed spontaneous and progressive decrease in the cyst size.

LESSONS

We illustrate a case of regression of an interhemispheric arachnoid cyst in a pediatric patient. To our knowledge, this is the first reported case of spontaneous shrinkage of an arachnoid cyst in this location. Although the current presentation is rare, this reporting adds to the current understanding of natural history of arachnoid cysts and provides an example of radiographical improvement without intervention of a cyst located within the interhemispheric fissure.

An Unusual Case of an Intradiploic Arachnoid Cyst of the Orbit

This study reported a case of an arachnoid cyst of the sphenoid bone causing orbital signs and symptoms in a 58-year-old man with progressive proptosis and nonspecific discomfort in the OS. Orbital MRI showed a 3-cm homogeneous cyst within the left greater wing of the sphenoid bone. To the best of our knowledge, this is the first report of an intradiploic arachnoid cyst in the sphenoid bone with atypical radiological features, causing clinical symptoms, and managed through an eyelid approach, achieving a complete resolution with no complications.

Structural deviations of the posterior fossa and the cerebellum and their cognitive links in a neurodevelopmental deletion syndrome

High-impact genetic variants associated with neurodevelopmental disorders provide biologically-defined entry points for mechanistic investigation. The 3q29 deletion (3q29Del) is one such variant, conferring a 40-100-fold increased risk for schizophrenia, as well as high risk for autism and intellectual disability. However, the mechanisms leading to neurodevelopmental disability remain largely unknown. Here, we report the first in vivo quantitative neuroimaging study in individuals with 3q29Del (N = 24) and neurotypical controls (N = 1608) using structural MRI. Given prior radiology reports of posterior fossa abnormalities in 3q29Del, we focused our investigation on the cerebellum and its tissue-types and lobules. Additionally, we compared the prevalence of cystic/cyst-like malformations of the posterior fossa between 3q29Del and controls and examined the association between neuroanatomical findings and quantitative traits to probe gene-brain-behavior relationships. 3q29Del participants had smaller cerebellar cortex volumes than controls, before and after correction for intracranial volume (ICV). An anterior-posterior gradient emerged in finer grained lobule-based and voxel-wise analyses. 3q29Del participants also had larger cerebellar white matter volumes than controls following ICV-correction and displayed elevated rates of posterior fossa arachnoid cysts and mega cisterna magna findings independent of cerebellar volume. Cerebellar white matter and subregional gray matter volumes were associated with visual-perception and visual-motor integration skills as well as IQ, while cystic/cyst-like malformations yielded no behavioral link. In summary, we find that abnormal development of cerebellar structures may represent neuroimaging-based biomarkers of cognitive and sensorimotor function in 3q29Del, adding to the growing evidence identifying cerebellar pathology as an intersection point between syndromic and idiopathic forms of neurodevelopmental disabilities.

Not Dandy Walker variant: a review of prominent retrocerebellar CSF space in children

The prominent retrocerebellar cerebrospinal fluid (CSF) space can be frequently encountered on paediatric neuroimaging studies. In cases involving abnormal vermian development where imaging does not align with the established criteria of Dandy-Walker malformation (DWM), the term "Dandy-Walker variant or continuum" has been historically employed to describe the aberrant posterior fossa development. Instead, the emphasis is on a more elaborate description of the findings in the posterior fossa. Moreover, combining the findings in the supratentorial brain can occasionally predict certain neurogenetic disorders that mimic Dandy-Walker phenotype. The present review demonstrates and differentiates the imaging features of various entities that result in an enlarged retrocerebellar CSF space, such as inferior vermian hypoplasia (IVH) and several neurogenetic conditions.

Surgical treatment of interhemispheric arachnoid cysts

OBJECTIVE

In children, interhemispheric arachnoid cysts (IHACs) are rare lesions often associated with corpus callosum dysgenesis. It is still controversial about surgical treatments for IHACs. We aim to report our experience with pediatric IHAC patients and evaluate surgical courses and neurological developments.

METHODS

Pediatric IHACs treated between 2001 and 2021 were reviewed retrospectively. IHAC was observed until they represented rapid cyst enlargement or neurological symptoms. Cyst fenestration was done by microscope or endoscope, depending on the IHAC's location. Cyst size and corpus callosum dysgenesis were evaluated with neuroimaging. Neurological development was assessed from medical records at the last follow-up.

RESULTS

Fifteen children received cyst fenestration surgery (mean age 11.4 months). Eleven patients (73.3%) under observation showed rapid cyst enlargement in a short period (median 5 months). Cysto-ventriculostomy (CVS) and cysto-cisternostomy (CCS) regressed the cyst size significantly (p = 0.003). The median follow-up duration was 51 months (range 14-178 months). Corpus callosum dysgenesis was observed in eleven patients (73.3%, complete = 5, partial = 6). Among eight patients (53.3%) having developmental delay, five patients (33.3%) showed speech delay, including one patient with intractable seizures.

CONCLUSION

Pediatric IHACs frequently present within 1 year after birth, with rapid cyst enlargement. CVS and CCS were effective in regressing the cyst size. Corpus callosum dysgenesis accompanied by IHAC might have a risk of language achievement; however, development delay could rely on multifactorial features, such as epilepsy or other brain anomalies.

Large intradiploic arachnoid cyst of the skull in child-a case report and new terminology proposition

We present a rare finding of the arachnoid matter invaginating into the base of middle cranial fossa and creating an abnormal space. Presented entity was incidentally found in head CT scan of 12-year-old male. Based on the radiological characteristics in CT scans and MR images, the diagnosis of intradiploic arachnoid cyst (AC) was suggested. After surgical intervention and histopathological analysis of the specimen, the diagnosis was confirmed. We assume this is the first description of large intrasphenoid AC without any traumatic or iatrogenic cause. The literature provides many different terms for the phenomenon. We are proposing the term intradiploic arachnoid diverticulum as the more accurate for capturing the essence of the phenomenon. It provides clear differentiation of the entities from classical arachnoid cysts since they are of different anatomical localization (intradural vs. extradural) and etiopathogenesis. Management with arachnoid diverticulum is not yet established, but observation with serial imaging studies should be recommended as primary management in case of asymptomatic cyst. When cyst is symptomatic, surgical treatment may be required.

Global trends and decision-making in the management of arachnoid cysts

OBJECTIVE

In pediatric patients, middle cranial fossa (MCF) arachnoid cysts are often discovered incidentally on imaging in asymptomatic patients during workup for other indications. This study aims to describe current management gestalt and threshold for surgical intervention by surveying an international cohort of neurosurgeons.

METHODS

A web-based survey was circulated via email list of attendants of the 2019 Canadian Pediatric Neurosurgery Study Group (CPNSG) and International Society of Pediatric Neurosurgery (ISPN) mailing list. The survey consisted of 8 clinical scenarios involving patients with MCF arachnoid cysts. Demographic variables of respondents and their decisions regarding management for each scenario were analyzed using R computing software.

RESULTS

A total of 107 respondents were included. Cysts in asymptomatic patients (92%), younger age at diagnosis (81%), and presence of a mild learning delay were predominantly managed non-surgically (80.7 ± 9.4%). Patients with cyst enlargement, headaches, new seizures, or hemorrhage were divided between non-surgical (55.8 ± 3.3%) and surgical (44.2 ± 2.9%) management. Patients with contralateral hemiparesis were treated predominantly surgically (67%). For both Galassi I and II, papilledema was favored as the primary indication for surgical intervention in 54% of patients. Those inclined to surgery (n = 17) were more likely to practice and train outside North America compared to those not pro-surgical (adjusted P = 0.092).

CONCLUSION

Incidental MCF arachnoid cysts in asymptomatic patients and younger age of diagnosis are predominantly managed non-surgically. Mild learning delay was not considered an indication to intervene. In contrast, radiological progression, hemorrhagic evolution, or non-focal neurological deficits lead to uncertainty in management, while focal neurological deficits and papilledema with MCF cysts were favored to be intervened surgically. Among the provider level factors, only location of training and practice trended towards a pro-surgery approach.

Prenatal dispositions and genetic analysis of monozygotic female twins with suprasellar cysts and hydrocephalus: A case report

INTRODUCTION

We present a unique case of monozygotic female twins with virtually identical clinical and radiological presentations of supratentorial hydrocephalus and cystic formations from the suprasellar cistern.

DISCUSSION

Evaluating genetic predispositions and prenatal exposures is crucial for hydrocephalus in twins. Familial cases imply a genetic contribution to the development of these anomalies, including chromosomal abnormalities and specific variants linked to arachnoid cyst formation in various syndromes. Extensive genetic analyses found no pathogenic variants in the twins. Prenatal exposure to anti-epileptic medication was known during pregnancy and may be associated with fetal abnormalities, but not central nervous system (CNS) malformations, and was therefore not considered the cause of the condition in the twins. The twins presenting simultaneously with hydrocephalus caused by suprasellar cysts (SAC) underwent a two-step surgical management: initial ventriculoperitoneal shunt (VPS) placement followed by fenestration. Postoperative imaging showed cyst reduction, but a secondary VPS was necessary in both cases.

CONCLUSION

Genetic analysis is less likely to identify a monogenic etiology in non-syndromic cases of SACs, which are assumed to be multifactorial. There is no established evidence linking a teratogenic effect of anti-epileptic drugs to CNS malformations. Moreover, the surgical treatment of this complex condition constitutes a point of discussion.

Subdural hemorrhage in middle cranial fossa arachnoid cysts: a report of two cases at two ends of the spectrum

Arachnoid cysts are usually asymptomatic, benign lesions commonly occurring in the middle cranial fossa. However, the cysts may rupture in rare cases causing intracystic or subdural hemorrhages with significant mass effect. We report two cases of middle cranial fossa arachnoid cyst with subdural hemorrhage with very different clinical course. The first case presented with significant mass effect with cerebral herniation and had significant neurological morbidity post-surgery. The second case had minimal symptoms and was managed conservatively with offer of elective surgery. The report underscores the importance of prompt diagnosis and appropriate surgical intervention in managing arachnoid cysts with hemorrhage, highlighting the potential for diverse clinical presentations and outcomes.

Arachnoid cyst presenting as a neurosurgical emergency: a case report

Introduction

Arachnoid cysts are intra-arachnoid lesions filled with cerebrospinal fluid. They account for ~1% of all intracranial mass lesions and are non-neoplastic collections of cerebrospinal fluid within an anomalous arachnoid enclosure.

Case presentation

The authors report a 35-year-old Arabian male who presented to the ER with a history of sudden loss of consciousness, anisocoria, and right hemiparesis. Contrast tomography showed a large frontoparietotemporal cyst (7.7×5.8×5.4) with uncal herniation and a midline shift of 12 mm. An emergency left FTP craniotomy with an excision of the cyst was performed.

Discussion

Arachnoid cysts can be categorized as primary or secondary, arising congenitally or due to factors like trauma, infection, or neoplasia. It can rupture, leading to internal bleeding, causing symptoms such as headaches, seizures, and neurological decline. Rapid diagnosis is vital, with cranial computed tomography scans preferred for emergencies. Treatment options include surgical intervention like craniotomy, fenestration, or cyst peritoneal shunts. For uncal herniation, surgery can be successful and results depends on the amount of herniation.

Conclusion

Although benign, the arachnoid cysts led to uncal herniation when they become 'tension' cysts. A high level of suspicion is crucial for early recognition of the condition. Timely intervention has shown positive recovery outcomes.

Does right hemisphere compensate for the left in school-age children with large left middle fossa arachnoid cysts?

BACKGROUND

To assess the cognitive function changes and brain network neuroplasticity in school-age children having large (diameter > 5 cm) left middle fossa arachnoid cyst (MFACs).

METHODS

Eleven patients and 22 normal controls (NC) between 6 and 14 years of age were included. The CNS Vital Signs (CNS VS) were administered for cognitive assessment. The differences of cognitive data and functional connectivity (FC) in resting-state functional magnetic resonance imaging (rs-fMRI) were compared between the patient group and the NC group. The correlations between the altered FC and cognitive data in the patient group were assessed.

RESULTS

Patient group had significantly poorer attention (including Complex Attention, Sustained Attention, Simple Attention, Cognitive Flexibility, and Executive Function) and memory function (Visual Memory and Working Memory) than the NC group (uncorrected p-value, p-unc < 0.05). Whole-brain local correlation (LCOR) analysis showed an extensively lower LCOR in the patient group (voxel threshold p-unc < 0.001, cluster-size threshold of false discovery rate adjusted p (p-FDR) < 0.001). Functional connectivity (FC) analysis showed that bilateral frontal and temporal lobes connectivity in the patient group was significantly lower than the NC group (p-FDR < 0.05). Seed-based FC analysis indicated that there was altered FC between the right temporal lobe and the left temporal-parietal/temporal-occipital area (p-FDR < 0.05). In the patient group, most of the altered FC had a negative correlation to the cognitive score, while the FC in the right temporal lobe-left temporal-occipital area positively correlated to Verbal/Visual Memory (r = 0.41-0.60, p-FDR < 0.05). In correlation analysis between clinical data and cognitive score, the only significant result was a low correlation between cyst size and Reaction Time (-0.30--0.36, P-FDR < 0.05).

CONCLUSIONS

School-aged children with large left MFAC showed significantly lower cognitive performance primarily in attention and memory domains. Distinct from neuroplasticity in a unilateral brain lesion, compensation in the healthy hemisphere in MFAC patients was sparse.

Sports Participation and Sports-Related Neurologic Injuries in Pediatric Patients With Arachnoid Cysts

BACKGROUND

Currently, there is no consensus recommendation regarding the safety of sports participation for pediatric patients with arachnoid cysts (ACs).

OBJECTIVE

To prospectively survey patients with ACs to define the risk of sports-associated neurologic injury in untreated and treated patients.

METHODS

A prospectively administered survey was given to all patients diagnosed with an AC who presented to a single pediatric neurosurgery clinic between December 2010 and December 2021. Data were recorded on demographic information, imaging characteristics, treatment, sports participation, and presence of sports-related neurologic injury. The type and date of surgery for the AC were noted if surgery was performed.

RESULTS

Of the 303 patients with completed surveys, 189 patients participated in sports, and 94 patients had prospective data available. There was no significant difference in cyst location or Galassi score between patients who did and did not participate in contact vs noncontact sports and those who did and did not experience a concussion. A cumulative total of 2700.5 seasons of sports were played (2499.7 in untreated and 200.8 in treated patients). There were 44 sports-related concussions among 34 patients: 43 in untreated patients and 1 in a treated patient. For all participants, the concussion rate was 16.3 per 1000 seasons of all sports and 14.8 per 1000 seasons of contact sports. The concussion rate after AC treatment was 4.9 per 1000 seasons of all sports. Three patients experienced sports-related AC rupture or hemorrhage, none of which required surgery or resulted in lasting neurologic symptoms or deficits.

CONCLUSION

The rates of sports-related concussion and cyst rupture in patients with AC in both treated and untreated populations were low. We advocate for a generally permissive posture toward sports participation in this population.

Clinicoradiologic Risk Stratification and Outcome Assessment in Symptomatic Intracranial Arachnoid Cyst Managed Over Fifteen Years

BACKGROUND

Arachnoid cysts (ACs) are developmental anomalies formed by splitting the arachnoid membrane's layers. ACs contribute around 2% of all intracranial space-occupying lesions. ACs are more prevalent in children. Because of varied clinical presentation, there has been a constant need for clinicoradiologic risk stratification with a possible role in outcome prediction. The present study describes the management strategies and outcomes in symptomatic intracranial ACs.

METHODS

All biopsy-proven symptomatic patients who underwent surgical management over last 15 years were included in this study (January 2008-December 2022), while those with non-conclusive biopsies were excluded. Patients presenting with acute deterioration were managed in the emergency department with or without cerebrospinal fluid diversion and decompression of the AC. The microsurgical or endoscopic approach was the preferred surgical modality. Postoperative clinicoradiologic improvement was evaluated at 3 months follow-up visit.

RESULTS

A total of 108 patients were analyzed in this retrospective observational study. The median age of the patients was 27.5 years (range, 1 to 76 years). Headache was the most typical clinical presentation. Supratentorial ACs (n = 59, 54.6%) were higher than the infratentorial ACs (n = 49, 45.4%). Forty-seven patients belonged to the pediatric age group (<18 years), and seizure was their presenting complaint. In this observational study, there was no statistical difference in operative duration between microsurgical technique versus endoscopic decompression (P= 0.23).

CONCLUSIONS

ACs are uncommon brain lesions having a broad spectrum of symptoms. The location and clinical presentation of ACs decide the preferred surgical approach. Individuals in high-risk groups must be treated on priority to achieve long-term relief of symptoms.

Growing and symptomatic intracranial arachnoid cyst in an elderly patient: a case report and literature review

We report an elderly patient with a symptomatic and growing arachnoid cyst. Physician should be cautious in counseling asymptomatic arachnoid cyst patients, regardless of their age, and inform them of the possibility, although rare, of growth and symptom development even in their late life.

MRI findings in children with migraine or tension-type headache

PURPOSE

Migraine and tension-type headache are common primary headaches in children. There is a risk of developing secondary headache in children. The current study was aimed to evaluate magnetic resonance imaging findings (MRI) in children with migraine or tension-type headache.

METHODS

The study was planned in children with migraine or tension-type headaches who have been followed up in the pediatric neurology outpatient clinic with regular office visits for at least two years and had neuroimaging in the last year.

RESULTS

280 patients (187 female patients) datas were studied. 91 (61 female patients) were followed up with the diagnosis of migraine and 189 (126 female patients) with the diagnosis of tension-type headaches. The age of patients was found to be 13.1 ± 3.4 years. Brain tumor was found in one child with tension-type headache who had papilledema. Incidental MRI findings found 7.7% and 12.7% in migraine and tension-type headache, respectively. MRI findings in the study were arachnoid cyst (14), pituitary adenoma (6), mega cisterna magna (6), pineal cyst (3), non-specific gliosis (2) and tumor (1).

CONCLUSION

Arachnoid cysts were found incidental as the most common MRI finding in children with migraine or tension-type headache. The rare life-threatening secondary headache may develop in children. The fundus examination as a complement to the neurological examination can be useful for requesting MRI.

Factors that Influence Subdural Hemorrhage Secondary to Intracranial Arachnoid Cysts in Children

OBJECTIVE

This study aimed to investigate factors that influence subdural haemorrhage (SDH) secondary to intracranial arachnoid cysts (IACs) in children.

METHODS

Data of children with unruptured IACs (IAC group) and those with SDH secondary to IACs (IAC-SDH group) were analyzed. Nine factors, sex, age, birth type (vaginal or caesarean), symptoms, side (left, right, or midline), location (temporal or nontemporal), image type (I, II, or III), volume, and maximal diameter, were selected. IACs were classified as types I, II, and III according to their morphological changes observed on computed tomography images.

RESULTS

There were 117 boys (74.5%) and 40 girls (25.5%); 144 (91.7%) patients comprised the IAC group and 13 (8.3%) comprised the IAC-SDH group. There were 85 (53.8%) IACs on the left side, 53 (33.5%) on the right side, 20 (12.7%) in the midline region, and 91 (58.0%) in the temporal region. The univariate analysis showed significant differences in age, birth type, symptoms, cyst location, cyst volume, and cyst maximal diameter (P < 0.05) between the 2 groups. Logistic regression using the synthetic minority oversampling technique model showed that image type III and birth type were independent factors that influenced SDH secondary to IACs (β0 = 4.143; β for image type = -3.979; β for birth type = -2.542) and that the representative area under the receiver-operating characteristic curve value was 0.948 (95% confidence interval, 0.898-0.997).

CONCLUSIONS

IACs are more common in boys than in girls. They can be divided into 3 groups according to their morphological changes on computed tomography images. Image type III and caesarean delivery were independent factors that influenced SDH secondary to IACs.

Intracranial arachnoid cysts: What is the appropriate surgical technique? A retrospective comparative study with 61 pediatric patients

Objective

Symptomatic intracranial arachnoid cysts (ACs) should be treated either through microsurgical (MS) or endoscopic surgical (ES) fenestration. Implantation of cysto-peritoneal shunt (CPS) system is another treatment option with decreasing indication. In our study, we compared the complication and revision rates between the three operative techniques in pediatric patients.

Methods

We included patients below 18 years with symptomatic intracranial ACs operated between 2004 and 2021. Initial symptoms, location, complication rate, clinical and radiological improvement, postoperative events and revision rate were compared retrospectively.

Results

Sixty-one patients; 33 (54.1%) MS operated (mean age 7.6 years), 18 (29.5%) ES operated (mean age 6.2 years) and 10 (16.4%) with CPS (mean age 3.0 years) were collected. The most common initial symptom was headache in 45.9%. 20 (32.8%) postoperative events were documented. The highest revision rate (60%) was seen in the CPS group compared to 33.3% in MS group and 16.7% in ES group. 31 patients harbored perisylvian ACs, 89% remained event-free after ES, 71% after MS and 20% after CPS. Clinical improvement immediately after surgery was observed in 58 patients (96.9% in MS, 88.9% in ES and 100% in CPS). A radiological volume reduction could be proven postoperative in 51 patients (78.8% MS, 88.9% ES and 90% CPS).

Conclusion

Endoscopic fenestration of AC is a safe and efficient technique which is being widely used nowadays with the highest event free survival compared to microsurgical fenestration especially in perisylvian arachnoid cysts. CPS shows on long terms the highest revision rate but carries the least surgical risks.

Spontaneous resorption of a convexity arachnoid cyst associated with intracystic hemorrhage and subdural hematoma: A case report

Background

Intracranial arachnoid cysts (ACs) are developmental anomalies usually filled with cerebrospinal fluid (CSF), rarely resolving throughout life. Here, we present a case of an AC with intracystic hemorrhage and subdural hematoma (SDH) that developed after a minor head injury before gradually disappearing. Neuroimaging demonstrated specific changes from hematoma formation to AC disappearance over time. The mechanisms of this condition are discussed based on imaging data.

Case Description

An 18-year-old man was admitted to our hospital with a head injury caused by a traffic accident. On arrival, he was conscious with a mild headache. Computed tomography (CT) revealed no intracranial hemorrhages or skull fractures but an AC was seen in the left convexity. One month later, follow-up CT scans showed an intracystic hemorrhage. Subsequently, an SDH appeared then both the intracystic hemorrhage and SDH gradually shrank, with the AC disappearing spontaneously. The AC was considered to have disappeared, along with the spontaneous SDH resorption.

Conclusion

We present a rare case where neuroimaging demonstrated spontaneous resorption of an AC combined with intracystic hemorrhage and SDH over time, which may provide new insights into the nature of adult ACs.

Symptomatic intracranial hypertension in an adult patient with spinal muscular atrophy and arachnoid cysts receiving nusinersen

 In patients with spinal muscular atrophy (SMA) headache after intrathecal administration of nusinersen is usually attributed to post-lumbar puncture syndrome. However, lumbar puncture opening pressure (LOP) has also been reported to be increased in children with SMA, both before and after treatment with nusinersen, although symptoms associated with increased LOP were not observed. We report to our knowledge the first case of symptomatic intracranial hypertension in an adult SMA patient. This 21-year-old man suffered from headache and vomiting followed by visual disturbances after the 12th injection of nusinersen. Bilateral papilledema was recognized ophthalmologically. MRI of the head showed signs of intracranial hypertension and additionally arachnoid cysts but not hydrocephalus. Symptoms resolved after 8 weeks of treatment with repeated lumbar punctures and acetazolamide. This case raises the possibility of intracranial hypertension as a complication of nusinersen therapy although arachnoid cysts represent another risk factor for intracranial hypertension. We recommend that patients suffering from headache after nusinersen injections should not only be questioned and examined for symptoms suggestive of post-lumbar puncture syndrome, but also intracranial hypertension.

Arachnoid cysts in paediatrics

PURPOSE OF REVIEW

Arachnoid cysts are incidentally found on neuroimaging at an increasing rate in the paediatric population. Hence, learning their clinical implications to better inform families is important. The purpose of this review is to outline the current understanding of epidemiology, disease and clinical features based on location, imaging and management of arachnoid cysts in paediatrics.

RECENT FINDINGS

The prevalence of arachnoid cysts is 2.6% in paediatrics, with greater than 90% being asymptomatic. When they do cause symptoms, it is based primarily on their location and size. The most accurate diagnostic modality is MRI. Recent literature focuses primarily on the origin of arachnoid cysts, new approaches to treating symptomatic arachnoid cysts and long-term implications for patients.

SUMMARY

Incidental arachnoid cysts are being found most often due to the more frequent use of neuroimaging. There is a higher prevalence for arachnoid cysts in men and they are more commonly found on the left side. Despite their impressive size or location, greater than 90% of these lesions are asymptomatic and require no intervention. However, follow up with neurosurgery to help determine the clinical significance of these lesions is essential.

Familial and syndromic forms of arachnoid cyst implicate genetic factors in disease pathogenesis

Arachnoid cysts (ACs) are the most common space-occupying lesions in the human brain and present significant challenges for clinical management. While most cases of ACs are sporadic, nearly 40 familial forms have been reported. Moreover, ACs are seen with increased frequency in multiple Mendelian syndromes, including Chudley-McCullough syndrome, acrocallosal syndrome, and autosomal recessive primary ciliary dyskinesia. These findings suggest that genetic factors contribute to AC pathogenesis. However, traditional linkage and segregation approaches have been limited in their ability to identify causative genes for ACs because the disease is genetically heterogeneous and often presents asymptomatically and sporadically. Here, we comprehensively review theories of AC pathogenesis, the genetic evidence for AC formation, and discuss a different approach to AC genomics that could help elucidate this perplexing lesion and shed light on the associated neurodevelopmental phenotypes seen in a significant subset of these patients.

Clinical value of classification in the treatment of children with suprasellar arachnoid cysts

OBJECTIVE

The aim of this study is to investigate the clinical characteristics and prognostic effects of different subtypes of suprasellar arachnoid cysts (SAC) in children.

METHODS

Fifty patients with primary SAC who had undergone endoscopic treatment in our department between January 2010 and December 2020 were studied retrospectively. All patients underwent endoscopic treatment after diagnosis, including ventriculocystostomy (VC) in 23 cases and ventriculocystocisternostomy (VCC) in 27 cases. All patients were followed up regularly after the operation, including head computed tomography (CT)/magnetic resonance imaging (MRI), and Evans index (EI) and frontal and occipital horn ratio (FOHR) index were measured to assess changes in cyst volume and hydrocephalus. The prognosis was evaluated comprehensively on the data of the improvement of clinical symptoms, child growth and development correlation score, and reduction of cyst volume 12 months after surgery. According to the new classification of SAC, 50 cases of children were classified into three groups in which we compared the clinical characteristics of different subtypes of the three groups. Logistic regression was used to analyze the influencing factors of prognosis.

RESULTS

Completed success was achieved in 50 cases, including 31 cases with cyst volume reduction of more than 50% and 19 cases with cyst volume reduction of less than 50%. The median follow-up time was 55.3 months (22 ~ 113 months). According to the new classification criteria of SAC, there were 21 cases of SAC-1, 16 cases of SAC-2, and 13 cases of SAC-3. There were no statistically significant differences among the three groups in gender, birth weight, prenatal diagnosis, hydrocephalus, endocrine abnormalities, relief of postoperative symptoms, cyst wall texture, and surgical methods (P > 0.05). There was a statistically significant difference among the three groups in the change of the cyst volume and the maximum cyst diameter (P < 0.05), in which SAC-1 had the largest volume reduction, SAC-2 was more likely to cause endocrine symptoms and SAC-3 was inclined to lie in between. Multivariate logistic analysis showed that SAC classification and cyst wall texture were independent risk factors for the prognosis.

CONCLUSION

The clinical characteristics of different SAC subtypes are different, and SAC classification is one of the independent risk factors affecting prognosis.

Multiomic analyses implicate a neurodevelopmental program in the pathogenesis of cerebral arachnoid cysts

Cerebral arachnoid cysts (ACs) are one of the most common and poorly understood types of developmental brain lesion. To begin to elucidate AC pathogenesis, we performed an integrated analysis of 617 patient-parent (trio) exomes, 152,898 human brain and mouse meningeal single-cell RNA sequencing transcriptomes and natural language processing data of patient medical records. We found that damaging de novo variants (DNVs) were highly enriched in patients with ACs compared with healthy individuals (P = 1.57 × 10^-33). Seven genes harbored an exome-wide significant DNV burden. AC-associated genes were enriched for chromatin modifiers and converged in midgestational transcription networks essential for neural and meningeal development. Unsupervised clustering of patient phenotypes identified four AC subtypes and clinical severity correlated with the presence of a damaging DNV. These data provide insights into the coordinated regulation of brain and meningeal development and implicate epigenomic dysregulation due to DNVs in AC pathogenesis. Our results provide a preliminary indication that, in the appropriate clinical context, ACs may be considered radiographic harbingers of neurodevelopmental pathology warranting genetic testing and neurobehavioral follow-up. These data highlight the utility of a systems-level, multiomics approach to elucidate sporadic structural brain disease.

Intracranial cysts: incidental or neurodevelopmental?

OBJECTIVES

Intracranial cysts are fluid-filled sacs within the brain. There is a diversity of intracranial cysts with different incidences in addition to the growing awareness about comorbidities and the consequences. The present study aimed to evaluate cystic findings in children who were admitted to the department of pediatric neurology.

METHODS

Children who were admitted to the Clinic of Pediatric Neurology and who had an MRI between 2016 and 2021 were evaluated. The MRI examination was performed with the pediatric epilepsy protocol. Children with primary intracranial cysts were enrolled in the study. Demographic and clinical findings were evaluated from the hospital's database and patients' files.

RESULTS

Among the 78 patients, 36 (46.2%) were male and 42 (53.8%) were female. The mean age was 7 ± 5.4 years. The most frequent presenting complaint was a seizure (47.4%). Approximately one-quarter (28.2%) had mental and/or motor retardation. Nine (11.5%) of the children had a neuropsychiatric diagnosis. Most of the cysts were located at the midline (41%) with the majority located extra-axial (71.8%) and supratentorial (78.2%). Arachnoid cysts were observed most frequently with a percentage of 64.1%, followed by pineal cysts (15.4%). The history of seizure, epilepsy, presence of mental retardation, and neuropsychiatric problems were evaluated according to the population ratios based on z approximation in which significantly higher rates were observed among cases with intracranial cysts.

CONCLUSION

Intracranial cysts should be taken into consideration for comorbid pathologies, especially in the childhood period. Early evaluation in patients with intracranial cysts for developmental delay and neuropsychiatric problems is important.

Embolization as adjunctive treatment to achieve complete cure of ruptured arachnoid cyst associated with chronic subdural hematoma

INTRODUCTION

Chronic Subdural Hematoma (CSDH) is a rare but classical evolutive complication of arachnoid cysts (AC). Its management has rarely been evaluated to date. Several approaches have been proposed including conservative and surgical treatments. Endovascular treatment in such CSDH subtype remains poorly reported.

CASE PRESENTATION

We present here an original case of a 16 years-old-boy suffering from ruptured AC responsible for CSDH successfully treated with embolization.

CONCLUSION

Endovascular approach may be considered in the treatment of CSDH related to arachnoid cyst rupture.

Effect comparison of neuroendoscopic vs. craniotomy in the treatment of adult intracranial arachnoid cyst

Purpose

Intracranial arachnoid cysts are common, accounting for about 1%-2% of intracranial space-occupying lesions. There is controversy over the method of surgical intervention, and in order to provide guidance for surgical decision making, this study compares the efficacy of craniotomy vs. neuroendoscopic surgery in treating arachnoid cysts.

Methods

The adult patients with arachnoid cyst admitted to our department from October 2016 to August 2021 were retrospectively analyzed. Thirteen adult patients were recruited, and divided into two groups: neuroendoscopic group (group A) and craniotomy group (group B). We compared the gender, age, clinical symptoms, preoperative and postoperative cyst sizes, symptom improvement, complications, length of hospital stay, and hospital costs between two groups to analyze the therapeutic effects of these two surgical methods.

Results

The cost of hospitalization in group A was significantly lower than that in group B (47,292.8 vs. 65,151.8 yuan, P < 0.05), and there was no difference in the length of hospital stay between the two groups. The preoperative cysts in group A were significantly larger than those in group B (6.38 vs. 2.97 cm, P < 0.05). In groups A and B, the short-term symptom improvement rates were 100% and 75.0%, respectively. The long-term symptom improvement rates were 77.78% and 75.0% (P > 0.05), respectively.

Conclusion

Both neuroendoscopic and craniotomy have good curative effects for the treatment of intracranial arachnoid cysts. There was no significant difference in the outcomes between the two surgical techniques. The cost of hospitalization can be reduced with neuroendoscopic surgery. Neuroendoscopic treatment is recommended for large intracranial arachnoid cysts, and craniotomy is suitable for small intracranial arachnoid cysts.

Temporal sylvian fissure arachnoid cyst in children: treatment outcome following microsurgical cyst fenestration with special emphasis on cyst reduction and subdural collection

OBJECTIVES

Controversy remains regarding surgical managements of sylvian fissure arachnoid cyst (SFAC). This review presents our experience in the microsurgical fenestration of pediatric patients with SFAC to define surgical indication, and risks and benefits with special emphasis on postoperative subdural fluid collection (SDFC) and cyst size reduction.

METHODS

Thirty-four children with SFAC who underwent microsurgical cyst fenestration at a single institution over a 10-year period were retrospectively reviewed for their clinical presentation, neuroimaging findings, and postsurgical course. The SFACs were classified by a novel grading system based on the degree of arachnoid cyst extension from the sylvian fissure to the insular cistern shown on MR images: grade 0 - little or no prominence of sylvian fissure, grade I - SFAC confined to the sylvian fissure, grade II - SFAC partially extending to the insular cistern, grade III - SFAC extending to the entire insular cistern.

RESULTS

There were 26 males and 8 females. SFAC was present in the left side in 24. Twelve patients presented with cyst rupturing to the subdural space. Cyst grading did not show significant difference compared with rupture status (p > 0.9). All patients underwent microsurgical cyst fenestration. Postoperative SDFC is common but often resolved overtime in two-thirds of the cases with the mean average of 6 months. However, 3 patients had symptomatic postoperative SDFC and needed reoperation shortly after the first operation. Microsurgical cyst fenestrations for SFAC effectively resolved the presenting symptoms and often showed restorations of intracranial structures on follow-up imaging. Cyst resolution or reduction greater than 75% was noted in 61.8% of the patients postoperatively which was noted in a half of the SFAC of children even with age of 11 years or older. During the follow-up, no cyst recurrence or SDFC was noted. Patients with greater surgical reduction of cyst size tended to occur in younger children, and those with lower MR grade.

CONCLUSION

Our results showed a high reduction rate of SFAC and brain re-expansion after microsurgical fenestration together with symptomatic improvements regardless the patient's age. Considering the developing CNS during childhood, reductions of a large space-occupying lesion followed by restorations of the structural integrity of the developing brain are very desirable. However, a multi-center cooperative prospective longitudinal study on long-term comparative data of those treated and untreated of neuro-psychological outcome and cyst rupture incidence is needed.

Surgical indications in pediatric arachnoid cysts

INTRODUCTION

Arachnoid cysts are developmental lesions consisting of CSF collections within the subarachnoid space. There are many theories and hypotheses about their pathogenesis and histopathology and this may also explain the diversities seen in clinical behaviors of these cysts, their natural history and consequently their management where there is a great controversy about selecting patients for surgical intervention. The most common location in pediatrics is the Sylvian or middle cranial fossa and this made it gain more concern and greater debate about its management where its diagnosis is often accidently or associated with nonspecific symptoms.

AIM

Our aim in this article was to review the main surgical indications for pediatric arachnoid cysts in the literature.

CONCLUSION

We concluded that the decision for surgical intervention for pediatric arachnoid cysts is not a simple one and highly debatable and should be taken cautiously especially with sylvian arachnoid cysts that may reach a large size without symptoms. However, there is a consensus that the occurrence of symptoms definitely correlated to the presence of these cysts or their rupture with consequent subdural hematoma or hygroma are indications for surgical intervention. Large cysts in locations compressing CSF pathways causing hydrocephalus are also candidates for surgical fenestration. The surgical gain from prophylactic surgery is questionable particularly when asymptomatic.

Right Trochlear Nerve Palsy as an Uncommon Manifestation of Arachnoid Cyst

The majority of arachnoid cysts are congenital intracranial lesions that develop in the early embryonic stages as a result of a slight irregularity in the cerebrospinal fluid's (CSF) passage through the embryonic mesenchyme. Most of the time, these cysts are asymptomatic all throughout life. Diplopia caused by an arachnoid cyst is extremely rare. We present a rare event of isolated fourth nerve palsy in a 56-year-old woman brought on by an intracranial arachnoid cyst. Her only presenting symptom was vertical diplopia for one week. She denied any history of trauma. Ocular motility revealed limitation of abduction in her right eye. We proceeded with neuroimaging and the magnetic resonance imaging (MRI) confirmed the presence of a well-circumscribed left retro-cerebellar lesion which follows the CSF signal intensity in all sequences causing compression onto the posterior aspect of the left cerebellum, keeping with the diagnosis of an arachnoid cyst. This uncommon pathology tends to be difficult to diagnose and treat.

Controversies in the Treatment of Arachnoid Cysts with Special Emphasis on Temporal Arachnoid Cysts

Intracranial arachnoid cysts (ACs) are benign lesions. The incidence in children is 2.6%. ACs are often diagnosed incidentally. Because of the broad use of CT and MR imaging, the frequency of AC diagnosis has increased. In addition, prenatal diagnosis of ACs is becoming more common. This places clinicians in a difficult situation with regard to the optimal treatment, since the presenting symptoms are often vague and operative management includes not negligible risks. It is generally accepted that conservative management is indicated in cases with small and asymptomatic cysts. In contrast, patients with definite signs of raised intracranial pressure should be treated. There are however clinical situations in whom the decision about the preferred treatment is difficult to make. Unspecific symptoms such as headaches and neurocognitive or attention deficits can be challenging to evaluate, whether they are related to the presence of the AC or not. The treatment techniques intent to establish a communication between the cyst and the normal cerebrospinal spaces or consist of a diversion of the cyst fluid by a shunt system. Which surgical method (open craniotomy for cyst fenestration, endoscopic fenestration, or shunting) is preferred differs between neurosurgical centers or the pediatric neurosurgeon in charge. Each treatment option has a unique profile of advantages and disadvantages which should be considered when discussing treatment with the patients or their caregivers.

Predictors for the clinical prognosis of sylvian arachnoid cysts in children

Objectives

To investigate the potential factors affecting the clinical prognosis of intracranial sylvian arachnoid cysts(IAC) in children.

Methods

All patients with IAC admitted to our department from January, 1, 2015 to December, 31, 2016, were retrospectively reviewed. Patients were grouped based on surgical treatment (surgery cohort vs non-surgery cohort). The clinical and image outcome of the patients were followed routinely. The clinical characteristics and the prognosis of the patients were compared in different cohorts. Binary logistic regression analysis was applied to analyze the potential factors which may post an influence on the prognosis of the patients.

Results

Of 500 patients admitted to our department for IAC, 424 patients had good prognosis and 76 had poor prognosis, with no deaths occurred during the follow-ups. 68 patients had IAC related complications and 91 patients developed new symptoms during the follow-ups. There were significant differences (P < 0.05) between the 2 cohorts in below aspects: age, gender, Galassi subtype, whether the mother was a unipara, the maximum diameter of the cysts at the first visit and the last follow-up, headache, head circumference, temporal bulge, new symptoms, cysts rupture and hemorrhage, subdural effusion, and IAC disappearance. The mean changes in the maximum diameter of the IAC for the patients were marginally higher for the surgery cohort than for the non-surgery cohort (P < 0.01). Binary logistic regression analysis suggested that the number of symptom, no new symptoms during follow-up, surgical treatment, age, maximum diameter of cysts at first diagnosis were independent risk factors affecting the prognosis of patients (P < 0.05).

Conclusions

Patients older than 22.5 months, with the maximum diameter of IAC greater than 5.75 cm, who have multiple symptoms, born prematurely, develope new symptoms during the follow-ups and obvious symptoms after trauma need to conduct necessary surgical treatment in time. Patients with complications such as cysts rupture with hemorrhage and subdural effusion will acquire good prognosis after timely surgical treatment. IAC complete disappearance warrants no such important attention for the good prognosis.

Understanding intracranial arachnoid cysts: a review of etiology, pathogenesis, and epidemiology

Arachnoid cysts (AC) are one of the common pathologies encountered in pediatric neurosurgical settings. It comes to clinical attention more often incidentally but also more often than previously due to the wide availability of diagnostic imaging. However, the accurate incidence and prevalence remain unknown. There is an ongoing debate on symptomatology, indications of treatment, and best treatment modalities. In this review, we aimed to discuss the current general knowledge about the arachnoid cyst, focusing on the etiology, pathogenesis, and epidemiology. Specific findings related to locations, such as the Sylvian fissure, are also emphasized.

Ultrasound and magnetic resonance imaging features of fetal intracranial cystic lesions: A pictorial essay

This pictorial essay focuses on ultrasound (US) and magnetic resonance imaging (MRI) features of fetal intracranial cysts. Intracranial cysts are common findings in prenatal imaging, and if great attention is paid to their size, location, and imaging features, they can be diagnosed accurately. They are usually detected by fetal ultrasound exams. However, when ultrasound data on cystic lesion characteristics is insufficient, MRI and fetal neurosonogram are the best options for detecting other associated anomalies. The prognosis is highly dependent on their location and whether they are associated with other fetal anomalies.

Postnatal Posterior Fossa Arachnoid Cyst: A Developmental Etiology to Be Considered

Intracranial arachnoid cyst is the most common cystic congenital anomaly in the brain. In this study, we discuss a pregnancy that had serial fetal ultrasound scans throughout the pregnancy and a fetal anomaly scan at 24 weeks of gestation that was normal. The child was born healthy with normal development, but 12 months onward the head began to enlarge. The magnetic resonance imaging of the brain showed a large posterior fossa arachnoid cyst with hydrocephalus. We discuss the postulation to explain this pathogenesis of the cyst. This case highlights that not all symptomatic arachnoid cysts are congenital despite the manifestation being as early as infancy.

Nonneoplastic and noninfective cysts of the central nervous system: A histopathological study

Nonneoplastic epithelial cysts involving the central nervous system are diverse and are predominantly developmental in origin. This study represents a surgical series describing the histopathological features of 507 such epithelial cysts with clinical and imaging correlation. Age at surgery ranged from 7 months to 72 years (mean: 33 years) affecting 246 male and 261 female patients. Colloid cyst was the most frequently resected cyst, followed by epidermoid cyst, arachnoid cyst, Rathke cleft cyst, dermoid cyst, neurenteric cyst, Tarlov cyst, and choroid plexus cyst. Diagnosis was based on the location of the cysts and the nature of the lining epithelium. Rathke cleft cyst showed the highest propensity for squamous metaplasia, significant inflammation, and xanthogranulomatous reaction. Ulceration of lining epithelium and calcification were most frequent in dermoid cyst. Radiopathological concordance was maximal for colloid cyst, followed by epidermoid and arachnoid cysts. Epidermoid and dermoid cysts exhibited the highest propensity for local tumor progression, followed by Rathke cleft cyst.

Characteristic and management of pediatric arachnoid cysts: A case series

Background/Aim: Arachnoid cysts (ACs) are the collection of fluid, which is similar in composition to cerebrospinal fluid, within the congenitally duplicated arachnoid membrane. ACs are clinically silent lesions, but sometimes they can manifest themselves with headache, convulsion, focal neurological deficits, cognitive decline, torticollis, and macrocephaly. Although the appropriate surgical approach is less clear, there is a consensus on the need for surgical treatment in symptomatic ACs. This study aims to reveal the advantages and disadvantages of cystoperitoneal shunt and microsurgical fenestration techniques. Methods: One hundred ninety-one consecutive patients from 1 month to 15 years old with AC were evaluated for suitability. Sixteen patients who underwent surgery were included in the study. Medical records of the patients with AC managed at our institutions were retrospectively collected and analyzed. Sixteen of 191 patients underwent surgical treatment via craniotomy for microsurgical cyst fenestration (CF) and cysto-peritoneal shunting (CS). CF was performed with partial cyst wall excision in all patients. Results: Seizure was the most common presentation in the patients, followed by headache and trauma, respectively. In our series the most common indications of the surgery were increased intracranial pressure (IICP). CF was performed in nine patients, and CS was performed in seven as the primary treatment. CS-related complications, such as infection (n = 2), dysfunction (n = 2) and intraabdominal abscess (n = 1) were the most commonly observed complications. No infections were observed after CF, but subdural hematoma was observed in one child. Conclusions: Although the most common symptoms in cases with arachnoid cysts are headache, rare symptoms, such as torticollis, may exist. Due to this, clinicians should reveal the cyst-complaint relationship first. Given the increased complications of CS, in addition to shunt independency and being free from shunt-related complications, the microsurgical CF with wide excision of the membranes seems to be the more preferable surgical option.

Temporosylvian arachnoid cysts in children. Part 2: Postoperative neuropsychological and clinical improvement

OBJECTIVE

The authors' objective was to study clinical, imaging, and neuropsychological changes in children who underwent surgery for a temporal arachnoid cyst (TAC).

METHODS

Thirty-four children were prospectively assessed similarly at diagnosis and postoperatively (mean 14 months) with clinic visits, images, cognitive tests, and parental questionnaires on mood/behavior and executive functions. The scores were compared pre- and postoperatively for the entire cohort and individually. The scores of 25 children were also compared with a control group of 23 healthy age-matched children. Parents were administered an outcome questionnaire on average 4 years postoperatively.

RESULTS

The 34 children selected for surgery had signs of raised intracranial pressure (74%) and/or selective neuropsychological disorders presumably linked to cyst location (learning difficulties in 65%, cognitive difficulties in 56%, and mood/behavior difficulties in 47%). The majority of patients had a convex cyst (85%) and underwent microsurgical fenestration (85%). The TAC volume decreased ≥ 50% for 59% of children. On the Wechsler Intelligence Scale, the entire cohort significantly improved on Full Scale IQ and verbal and perceptual nonverbal indexes. Individually, nearly half of the children (47%) highly increased their scores (≥ 15 points) on at least one IQ index and 26% on at least two indexes. Language, working memory, episodic memory, and executive functions were also significantly improved. Improvements were more pronounced in patients with a preoperative heterogeneous profile with isolated lower scores and a left-sided cyst. Parental questionnaires showed reduction in anxiety, aggressiveness, social problems, and daily life executive disorders. Preschool-aged children improved significantly in language and verbal IQ, as did middle/high school-aged children in many domains. Individual analyses revealed improvement in 76% of cases. Cognitive scores were lower for patients preoperatively than for controls and were no longer significantly different postoperatively in verbal fluency, visual memory, and working memory. Four years later, 97% of parents described an improvement in their child, correlated with cognitive improvements.

CONCLUSIONS

Among children with a TAC, some have no clinical signs or neuropsychological difficulties, and others may show signs of raised intracranial pressure and/or specific neuropsychological disorders that impact daily life and require significant and long-lasting rehabilitation. In these cases, consideration may be given to surgical decompression. It is interesting to note that 76% of this surgically treated cohort improved regardless of the child's age, particularly in patients with selective disorders and an impact on daily life. However, a larger number of children will need to be investigated before the true benefit of such treatment can be known.

Acetazolamide to treat symptomatic ruptured arachnoid cysts: illustrative cases

BACKGROUND

Arachnoid cysts are benign, often asymptomatic intracranial mass lesions that, when ruptured, may cause seizures, raised intracranial pressure, hemorrhage, and/or loss of consciousness. There is no widely agreed upon treatment, and there is debate as to whether a nonoperative or surgical approach is the best course of action. The carbonic anhydrase inhibitor acetazolamide may be an effective nonoperative approach in treating ruptured arachnoid cysts.

OBSERVATIONS

The Pediatric Neurosurgery Clinical Database at BC Children’s Hospital from 2000 to 2020 was queried, and four pediatric patients who were treated with acetazolamide after presentation with a ruptured middle cranial fossa arachnoid cyst were identified. All patients showed some degree of symptom improvement. Three of the patients showed complete reabsorption of their subdural collections in the ensuing 6 months. One patient had an inadequate response to acetazolamide and required surgical management.

LESSONS

Acetazolamide is a safe and reasonable primary treatment option in pediatric patients with ruptured middle cranial fossa arachnoid cysts, and it may help avoid the need for surgery.

Supratentorial Pediatric Midline Tumors and Tumor-like Lesions: Clinical Spectrum, Natural History and Treatment Options

Childhood Central Nervous System tumors account for 25% of all pediatric tumors. Large availability and broadening of indications to imaging has made incidental findings more common. Among these, midline lesions have different clinical relevance depending on their intrinsic pattern of behaviour and on their specific location. In this narrative review we describe the natural history and treatment options of midline lesions in children.

Reversible hearing loss after 3D video-assisted marsupialization of several posterior fossa arachnoid cysts: A case report

Very few pediatric cases of arachnoid cyst of ponto-cerebellar angle are described in the literature. Only 4 are described with hearing loss. It is a pathology which poses especially a problem of early diagnosis. In this paper we describe the management of a 16-year-old patient with an arachnoid cyst of the cerebellopontine angle with an isolated auditory deficit that was treated surgically. The follow up was marked by a Full recovery of hearing after surgical treatment. Arachnoid cyst of the cerebellopontine angle is rare in the pediatric population. early surgical management help to increase the chances of recovery.

Surgical management of quadrigeminal cistern arachnoid cysts: case series and literature review

OBJECTIVE

Quadrigeminal cistern arachnoid cysts (QACs) are congenital lesions that can cause pineal region compression and obstructive hydrocephalus when sufficiently large. Management of these cysts is controversial and rates of reintervention are high. Given the limited data on the management of QACs, the authors retrospectively reviewed 20 years of cases managed at their institution and performed a literature review on this topic.

METHODS

The authors performed a retrospective analysis of patients treated for QAC at their institution between 2001 and 2021. They also performed a literature review of studies published between 1980 and 2021 that reported at least 5 patients treated for QACs. Patient characteristics, radiographic findings, management course, and postoperative follow-up data were collected and analyzed.

RESULTS

A total of 12 patients treated for a QAC at the authors' institution met the inclusion criteria for analysis. Median age was 9 months, mean cyst size was 5.1 cm, and 83% of patients had hydrocephalus. Initial treatment was endoscopic fenestration in 92% of these patients, 27% of whom had an endoscopic third ventriculostomy (ETV) performed concurrently. Reintervention was required in 42% of patients. Cases that required reintervention had a statistically significant lower median age at the initial intervention (5 months) than the cases that did not require reintervention (24.33 months; p = 0.018). There were no major complications. At a mean follow-up of 5.42 years, 83% of patients had improvement or resolution of their symptoms. A literature review revealed 7 studies that met the inclusion criteria, totaling 108 patients with a mean age of 8.8 years. Eighty-seven percent of patients had hydrocephalus at presentation. Ninety-two percent of patients were initially treated with endoscopic fenestration, 44% of whom underwent concurrent ETV. Complications occurred in 17.6% of cases, and reintervention was required in 30.6% of cases. The most frequent reason for reintervention was untreated or unresolved hydrocephalus after the initial procedure.

CONCLUSIONS

Endoscopic fenestration is the most common treatment for QACs. While generally safe and effective, there is a high rate of reintervention after initial treatment of QACs, which may be associated with a younger age at the first intervention. Additionally, identifying patients who require initial treatment of hydrocephalus is critically important, as the literature suggests that untreated hydrocephalus is a common cause of reintervention.