BACKGROUND: Intracranial arachnoid cysts (IAC) in children are a common incidental finding on imaging. Most IACs are asymptomatic and can be monitored; however, a small percentage may enlarge and require surgical intervention. This study aimed to identify clinical risk factors in patients with IAC who underwent surgery versus those who did not.
METHODS: We conducted a retrospective chart review from 2009 to 2021 at a free-standing children\'s hospital. A total of 230 patients diagnosed with an IAC aged 0-21 years of age were included in the study. Data on demographics, imaging, and neurological follow-up were analyzed.
RESULTS: Out of 230 patients, 45 (19.6%) underwent surgery. At time of IAC diagnosis, the surgical patients were younger (median age 1.1 years), and their median cyst volume was larger (41.7 cm3), compared to nonsurgical patients (median age 5.9 years, volume 11.8 cm3, respectively). Headache was the most common reason for initial imaging in nonsurgical patients (54/185, 29.2%) while prenatal ultrasound (11/45, 24.4%) and macrocephaly (11/45, 24.4%) were the most common reasons for surgical patients. The majority of both surgical and nonsurgical patients had the IAC incidentally found (41/45, 91.1% and 181/185, 97.8%, respectively). Surgery relieved symptoms in 38/45 (84.4%) patients. Cyst volume and age were predictors of increased odds of having surgery.
CONCLUSIONS: Patients who underwent surgery were younger and had larger cyst volumes at time of diagnosis. The majority of the IAC were found incidentally and remained stable over prolonged follow-up. The majority of the patients experienced relief of symptoms postsurgical intervention. There is a greater odds of having surgical treatment with decreased age and greater cyst volume at diagnosis, and therefore these patients should be monitored closely for development of symptoms indicating need for surgical intervention.

OBJECTIVE: The occurrence and predictors of symptomatic subdural hygroma (SSH) subsequent to the fenestration of pediatric intracranial arachnoid cysts (IACs) are unclear. In this study, the authors aimed to investigate the likelihood of an SSH following IAC fenestration and the impact on operative efficacy with the ultimate goal of constructing a nomogram.
METHODS: The medical records of 1782 consecutive patients who underwent surgical treatment at the Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine were reviewed. Among these patients, a training cohort (n = 1214) underwent surgery during an earlier period and was used for the development of a nomogram. The remaining patients formed the validation cohort (n = 568) and were used to confirm the performance of the developed model. The development of the nomogram involved the use of potential predictors, while internal validation was conducted using a bootstrap-resampling approach.
RESULTS: SSH was detected in 13.2% (160 of 1214) of patients in the training cohort and in 11.1% (63 of 568) of patients in the validation cohort. Through multivariate analysis, several factors including Galassi type, IAC distance to the basal cisterns, temporal bulge, midline shift, IAC shape in the coronal view, area of the stoma, and artery location near the stoma were identified as independent predictors of SSH. These 7 predictors were used to construct a nomogram, which exhibited a concordance statistic (C-statistic) of 0.826 and demonstrated good calibration. Following internal validation, the nomogram maintained good calibration and discrimination with a C-statistic of 0.799 (95% CI 0.665-0.841). Patients who had nomogram scores < 30 or ≥ 30 were considered to be at low and high risk of SSH occurrence, respectively.
CONCLUSIONS: The predictive model and derived nomogram achieved satisfactory preoperative prediction of SSH. Using this nomogram, the risk for an individual patient can be estimated, and the appropriate surgery can be performed in high-risk patients.

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

To review the literature and analyze the efficacy and safety of two surgery procedures, intracranial drainage and extracranial shunt, for intracranial arachnoid cysts.
We searched the online Medlars, PubMed, and Cochrane Central electronic databases and collected studies of patients with intracranial arachnoid cysts treated with two surgical methods.
The meta-analysis results shows that there were not statistically significant in clinical symptoms improvement, cyst reduction, the improvement of epilepsy, epidural hematoma, cerebrospinal fluid leak, and recurrence rate (P > 0.05, with RR values are 0.99, 0.94, 1.00, 0.94, 1.21, and 0.75 respectively). There was statistically significant in the occurrence rate of intracranial infection (P = 0.0004, RR = 0.28). The intracranial drainage group was lower than extracranial shunt group.
The results indicated that the efficacy and safety of two surgery procedures are similar in the treatment of intracranial arachnoid cysts, but the intracranial drainage was better than extracranial shunt in reducing the risk of intracranial infection.

BACKGROUND: Intracranial arachnoid cysts (AC) are benign, cerebrospinal fluid filled spaces within the arachnoid layer of the meninges. Neurosurgical intervention in children and young adults has been extensively studied, but the optimal strategy in the elderly remains unclear. Therefore, we performed a single center retrospective study combined with a systematic review of the literature to compare cystoperitoneal (CP) shunting with other surgical approaches in the elderly cohort.
METHODS: Retrospective neurosurgical database search between January 2005 and December 2018, and systematic review of the literature using PRISMA guidelines were performed. Inclusion criteria: Age 60 years or older, radiological diagnosis of intracranial AC, neurosurgical intervention, and neuroradiological (NOG score)/clinical outcome (COG score). Data from both sources were pooled and statistically analyzed.
RESULTS: Our literature search yielded 12 studies (34 patients), which were pooled with our institutional data (13 patients). CP shunts (7 patients; 15%), cyst fenestration (28 patients; 60%) and cyst marsupialisation/resection (10 patients; 21%) were the commonest approaches. Average duration of follow-up was 23.6, 26.9, and 9.5 months for each approach, respectively. There was no statistically significant association between choice of surgical intervention and NOG score (P = 0.417), COG score (P = 0.601), or complication rate (P = 0.955). However, CP shunting had the lowest complication rate, with only one patient developing chronic subdural haematoma.
CONCLUSIONS: CP shunting is a safe and effective surgical treatment strategy for ACs in the elderly. It has similar clinical and radiological outcomes but superior risk profile when compared with other approaches. We advocate CP shunting as first line neurosurgical intervention for the management of intracranial ACs in the elderly.

UNASSIGNED: Intracranial arachnoid cysts (ACs) are a cerebral spinal fluid (CSF) collection within the meninges. They typically arise during embryologic development. Some are stable overtime with little consequence, but large or growing cysts may require surgical intervention. The optimal surgical technique is debated and may be more technically challenging in the infant age group.
UNASSIGNED: Our unique case report details a 10-month-old (6 months corrected age) infant who presented with a drastic increase in head circumference and was found to have midline shift and three cysts - one large and two smaller ones. He was treated with an innovative surgical approach combining stereotactic introduction of a catheter to facilitate subsequent flexible endoscopy allowing three separate cysts to be treated through one small surgical incision with no complications and a stable examination on 2-year follow-up.
UNASSIGNED: Symptomatic ACs in the infant population that require treatment can be addressed with open surgery to fenestrate the cyst, endoscopic cyst fenestration, or cystoperitoneal shunting. Typically, surgeons must choose between a rigid endoscope which allows stereotactic navigation or a flexible endoscope which allows multiple trajectories but precludes navigation. Our case demonstrates that combining stereotactic ventricular placement before flexible endoscopy provides the benefit of both approaches and allows for successful endoscopic treatment in a young patient with durable results.

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.

Neuroendoscopy has become an effective and safe treatment for arachnoid cysts in the paediatric population. We review the paediatric patients with arachnoid cysts treated by neuroendoscopy in our hospital and analyse the results.
A retrospective analysis of 20 patients operated on from 2005 to 2018. The variables assessed are: gender, age, clinical presentation, cyst site, presence of hydrocephalus and/or extra-axial collections, endoscopic procedures and complications. Procedure success is defined as an improvement in symptoms and reduction in cyst size until end of follow-up.
Our series comprised 13 males and 7 females (mean age: 64.6 months, range: 4-172 months). The most frequent site was suprasellar-prepontine (7), followed by intraventricular (6), quadrigeminal (3), interhemispheric (2) and Sylvian (2). A total of 70% (14/20) of patients had hydrocephalus at diagnosis, which increased to 85% in suprasellar-prepontine cysts and 100% in quadrigeminal cysts. Only 4/14 patients with required a ventriculoperitoneal shunt (median age at diagnosis: 12.5 months). Of these 4 patients, 3 developed severe shunt overdrainage. The procedure was successful in 60% (12/20) of the patients in the series. Success by location was 57% (4/7) in suprasellar cysts, 33% (1/3) in quadrigeminal cysts, 66% (4/6) in intraventricular cysts, 100% (2/2) in interhemispheric cysts and 50% (1/2) in Sylvian cysts. Treatment thus failed in 8 cases, with a mean time to failure of 12.12 months (range: 0-45 months). A new neuroendoscopic procedure was performed in 4 of these 8 cases (success in 2/4), a ventriculoperitoneal shunt was placed in 2 cases, a cystoperitoneal shunt was placed in 1 case and the remaining case was managed conservatively. Mean follow-up time was 52.45 months (range: 3-129 months).
Neuroendoscopy is an effective and safe treatment for arachnoid cysts in paediatric patients that also enables managing associated hydrocephalus in most cases. The choice of neuroendoscopic procedure and success rate depend on cyst location. Younger patients have been found to have a higher shunt dependency rate. In these cases, measures to prevent shunt overdrainage are recommended.

OBJECTIVE Subjective improvement of patients who have undergone surgery for intracranial arachnoid cysts has justified surgical treatment. The current study aimed to evaluate the outcome of surgical treatment for arachnoid cysts using standardized interviews and assessments of neuropsychological function and balance. The relationship between arachnoid cyst location, postoperative improvement, and arachnoid cyst volume was also examined. METHODS The authors performed a prospective, population-based study. One hundred nine patients underwent neurological, neuropsychological, and physiotherapeutic examinations. The arachnoid cysts were considered symptomatic in 75 patients, 53 of whom agreed to undergo surgery. In 32 patients, results of the differential diagnosis revealed that the symptoms were due to a different underlying condition and were unrelated to an arachnoid cyst. Neuropsychological testing included target reaction time, Grooved Pegboard, Rey Auditory Verbal Learning, Rey Osterrieth complex figure, and Stroop tests. Balance tests included the extended Falls Efficacy Scale, Romberg, and sharpened Romberg with open and closed eyes. The tests were repeated 5 months postoperatively. Cyst volume was pre- and postoperatively measured using OsiriX software. RESULTS Patients who underwent surgery did not have results on balance and neuropsychological tests that were different from patients who declined or had symptoms unrelated to the arachnoid cyst. Patients with a temporal arachnoid cyst performed within the normal range on the neuropsychological tests. Seventy-seven percent of the patients who underwent surgery reported improvement, yet there were no differences in test results before and after surgery. Arachnoid cysts in the temporal region and posterior fossa did not influence the preoperative results of neuropsychological and motor tests. The arachnoid cyst volume decreased postoperatively (p < 0.0001), but there was no relationship between volume reduction and clinical improvement. CONCLUSIONS The results of this study speak against objectively verifiable improvement following surgical treatment in adults with intracranial arachnoid cysts.

OBJECTIVE: The management of posterior fossa arachnoid cyst (PFAC) in adults is controversial. To review our cases and literature, propose a practically useful surgical strategy, which gives excellent long-term outcome in management of PFAC.
METHODS: We analyzed our case records of 26 large intracranial arachnoid cysts in adults treated over 12 years. Of them, we had 7 patients with symptomatic PFAC. Reviewed the literature of 174 PFAC cases (1973-2012) and added 7 of our new cases with a follow-up ranging from 3 to 12 years.
RESULTS: In 6 cases the PFAC was located in the midline. In the 7(th) case, it was located laterally in the cerebello-pontine (CP) angle. All patients were treated surgically. Excision of the cyst was performed in 5 of these cases. Among the two intra-fourth ventricular cysts, in both the cases cysto-peritoneal shunt was performed. Postoperative computed tomography/magnetic resonance imaging showed variable decrease in size of the cyst even though clinically all patients improved. We propose a surgical strategy for the management of these cases which would aid the surgeon in decision making.
CONCLUSIONS: We observed that these PFACs can occur either in the midline within the fourth ventricle or retroclival region or extra-fourth ventricular region. It can also develop laterally in the CP angle or behind the cerebellum or as intracerebellar cyst. Importance of this is except for Midline Intra-fourth ventricular cyst/retroclival cyst, the rest all can be safely excised with excellent long term outcome. The treatment strategy for Midline Intra-fourth ventricular cyst/retroclival cyst can be either cysto-peritoneal shunt or endoscopic fenestration of the cyst.