Arachnoid Cyst Fenestration Research Articles

Intracranial arachnoid cyst complicated with subdural hygroma in a 10-year-old child: A case report and literature review

Arachnoid cysts are abnormal collections of fluids within the arachnoid membrane after a doubling of the structure. These benign lesions represent only 1% of all intracranial space-occupying lesions. The affected patient can remain asymptomatic for several years, which is an incidental finding in most cases. Cysts have been reported to rupture after a minor head trauma, causing subdural hygroma or hematoma; however, spontaneous rupture complicated with subdural hygroma has been rarely reported. Herein, we report a rare case of a 10-year-old boy whose pregnancy follow-up, delivery, and parent’s medical history were unremarkable. The patient was admitted for a temporal arachnoid cyst complicated with subdural hygroma, which was determined to be caused by intracranial hypertensive syndrome. He was successfully treated through endoscopic arachnoid cyst fenestration, wherein a pathway was created for the cyst to communicate with the subarachnoid space through the basal cisterns. The choice of treatment for arachnoid cysts remains controversial. Endoscopic treatment is considered when an ipsilateral subdural hygroma is present. Intracranial hypertensive syndrome subsided immediately after surgery. No post-operative complications occurred. The child recovered uneventfully in the post-operative period and was discharged 5 days after surgery. He underwent a follow-up computed tomography 1 month later, confirming a progressive regression of the hygroma as well as arachnoid cyst.

Middle fossa arachnoid cyst fenestration for ruptured cysts associated with subdural collections: paediatric neurosurgery tertiary unit experience.

Arachnoid cysts are commonly encountered benign cystic structures and often come to attention as incidental findings following cranial imaging. Surgical intervention rates vary in different studies; however, rupture of cyst and subdural collection with mass effect are some of the indications for surgical intervention. In this study, we aimed to evaluate our operated cohort of middle fossa arachnoid cysts to determine the rate of traumatic subdural collection in this cohort and further assess outcomes. A retrospective review of all consecutive operated middle cranial fossa arachnoid cysts was carried out for the period 2010 to 2024. Demographics including age, sex, Galassi type, surgical technique for fenestration, preceding history of trauma, presence of papilloedema, and complications following surgery were extracted. Indication for surgery included papilloedema and headaches or increasing head circumference or rupture and subdural collections. Arachnoid cysts managed with CSF diversion as primary surgery were excluded. Over the study period, 21 fenestrations of the arachnoid cysts were carried out in 19 patients with mean age of 7years and M:F ratio of 2.2:1 (laterality: 9 right-sided and 10 left-sided). These included seven Galassi 2 and twelve Galassi 3 arachnoid cysts. At presentation, 10 had papilloedema, 5 with no papilloedema, and 4 with no available ophthalmological assessment. Fenestration of cyst included 12 microscopic, 6 endoscopic, and 3 combined approaches. Of the operated cohort, 8 were due to rupture of arachnoid cyst and subdural collections causing mass effect. Of 8 cases of ruptured arachnoid cyst with subdural collections, 75% had clear history of preceding head injury in the context of accidental or sports-related injuries. Two patients required redo-fenestration (10.5%), 1 patient required temporary lumbar drain (5.2%), and 2 patients required cysto-peritoneal shunts (10.5%). Rupture of arachnoid cysts and subdural collections although rare can be associated with head injury in majority of cases. All operated cases belonged to grade 2 and 3 Galassi.

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

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. 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). 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. 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.

Purely Endoscopic Supracerebellar Infratentorial Approach to the Pineal Region in Pediatric Population.

Pineal lesions represent less than 1% of all brain tumors (Villani et al., Clin Neurol Neurosurg 109:1-6, 2007). The abysmal location and critical neurovascular structures remain a surgical challenge, despite the advent of microneurosurgery. The classical wide surgical suboccipital craniotomy with the supracerebellar infratentorial approach, described by Sir Victor Horsley (Victor, Proc R Soc Med 3:77-78, 1910), is infamous for its considerable surgical morbidity and mortality. This was later upgraded microneurosurgically by Stein to improve surgical outcomes (Stein, J Neurosurg 35:197-202, 1971).Ruge et al. reported the first purely endoscopic fenestration of quadrigeminal arachnoid cysts via this corridor (Ruge et al., Neurosurgery 38:830-7, 1996). A cadaver-based anatomical study by Cardia et al. demonstrated the viability for endoscope-assisted techniques (Cardia et al., J Neurosurg 2006;104(6 Suppl):409-14). However, the first purely endoscopic supracerebellar infratentorial (eSCIT) approach to a pineal cyst was performed in 2008 by Gore et al. (Gore PA et al., Neurosurgery 62:108-9, 2008).Unlike transventricular endoscopy, eSCIT approach poses no mechanical risk to the fornices and can be utilized irrespective of ventricular size. More vascular control and resultant reduction in uncontrolled hemorrhage improve the feasibility of attaining complete resection, especially around corners (Zaidi et al,, World Neurosurg 84, 2015). Gravity-dependent positioning and cerebrospinal fluid (CSF) diversion aid cerebellar relaxation, creating the ideal anatomical pathway. Also, angle of the straight sinus, tentorium, and tectal adherence can often influence the choice of approach; thus direct endoscopic visualization not only counteracts access to the engorged Galenic complex but also encourages sharp dissection of the arachnoid (Cardia et al., J Neurosurg 104:409-14, 2006). These tactics help provide excellent illumination with magnification, making it less fatiguing for the surgeon (Broggi et al., Neurosurgery 67:159-65, 2010).The purely endoscopic approach thwarts the dreaded risk of air embolisms, via simple copious irrigation from a small burr hole (Shahinian and Ra, J Neurol Surg B Skull Base 74:114-7, 2013). The tiny opening and closure are rapid to create, and the smaller wound decreases postoperative pain and morbidity. Recent literature supports its numerous advantages and favorable outcomes, making it a tough contender to traditional open methods.

Nomogram for preoperative estimation of symptomatic subdural hygroma risk in pediatric intracranial arachnoid cysts.

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. 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. 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. 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.

Microscope neuronavigation-guided microsurgical fenestration of quadrigeminal cistern arachnoid cysts: how I do it.

Management options for treatment of quadrigeminal arachnoid cysts (QAC) include microsurgical/endoscopic fenestration or shunt. There is an open debate about which method is the best. Microsurgical fenestration is well suited for treatment of QAC with predominant infratentorial component and without hydrocephalus making endoscopic procedures more challenging. We describe the microsurgical technique and related anatomy to fenestrate infratentorial QAC through supracerebellar infratentorial approach. We also discuss our experiences with this approach, some of the drawbacks and nuances. Navigation-guided microsurgical fenestration of infratentorial QAC is the authors' surgical approach of choice for treating these rare challenging lesions when not associated with hydrocephalus.

Flexible neuroendoscopy for endoscopic third ventriculostomy and fourth ventricular arachnoid cyst fenestration in an infant.

Arachnoid cysts of the fourth ventricle are rarely reported. Management options include CSF diversion, cyst fenestration, or cyst excision. Fenestration can be done via open microsurgical technique or endoscopically with or without simultaneous third ventriculostomy; and both rigid and flexible endoscopy have been used successfully. However, application of this treatment modality in pediatric patients is not well described. Therefore, to their knowledge, the authors report the first successful treatment of a fourth ventricular arachnoid cyst with a single frontal burr hole entry point for third ventriculostomy and fourth ventricular arachnoid cyst fenestration performed using flexible neuroendoscopy. The patient was a 13-month-old boy presenting with progressive macrocephaly. The authors review their technique, discuss special considerations when using this approach, and include an annotated intraoperative video for demonstration to help instruct and guide management. The authors demonstrate with an example that a single frontal burr hole entry point for flexible endoscopic third ventriculostomy and navigation through a dilated cerebral aqueduct for fourth ventricular arachnoid cyst fenestration is a viable treatment for symptomatic fourth ventricular arachnoid cysts in children.

Effectiveness of multiple endoscopic fenestrations for the treatment of Sylvian fissure arachnoid cysts: a multicenter study.

Arachnoid cysts are usually asymptomatic lesions. However, they can sometimes cause intracranial hypertension, headache, seizures, focal neurological deficits, and bleeding. The most commonly used surgical techniques are microsurgical cyst fenestration/excision/drainage, cyst shunting, and endoscopic procedures. We aimed to investigate the success of different surgical techniques. Between 2000 and 2021, patients with Sylvan fissure arachnoid cysts who received treatment via an endoscopic approach chosen as the first-line treatment in three centers were enrolled. All case notes and radiological studies were evaluated retrospectively. The study included 131 (female, n = 28; male, n = 103) patients with a mean age of 87.04 ± 66.76 (range, 0-216) months. Of the patients, 25 had Galassi type II left-sided arachnoid cysts, 33 had Galassi type II right-sided arachnoid cysts, 40 had Galassi type III left-sided arachnoid cysts, and 32 had Galassi type III right-sided arachnoid cysts. No difference was found between patients who underwent single and multiple fenestrations in terms of Galassi type, side, clinical outcome, and cyst size (p > 0.05). On the contrary, the rate of additional surgical intervention was lower in patients with multiple fenestrations than in those with single fenestration (36.10% vs. 5.30%; p < 0.001). Endoscopic fenestration of Sylvian fissure arachnoid cysts is a good alternative to open surgery or cystoperitoneal shunting, and the number of fenestrations made during this surgery decreases the need for a second surgical procedure.

Endoscopic Fenestration for Treating Galassi Type III Middle Cranial Fossa Arachnoid Cysts: Single- and Multiple-stoma have the Same Curative Effect.

For endoscopic fenestration of middle cranial fossa arachnoid cysts (MCFACs), the decisions on the location and number of stomas are key issues. However, research on this particular topic has been limited. Thus, this study aimed to compare single- versus multiple-stoma endoscopic fenestration for treating Galassi type III MCFACs. This retrospective study included 86 patients with Galassi type III MCFACs treated with endoscopic fenestration. Single-stoma fenestration to the basal cistern was performed in 37 cases, whereas multiple-stoma fenestration to the basal cistern and the carotid cistern was performed in 49 cases. Clinicoradiologic profiles and follow-up data were analyzed. The rate of symptom relief was 83.7% (72/86), and the rate of cyst shrinkage was 96.5% (83/86). Postoperative ipsilateral subdural effusion, which was significant (p = 0.042), and noninfectious fever were the two most common complications in the single- and multiple-stoma groups. No significant differences in intraoperative nerve injury, vascular injury, proportion of cases with cyst reduction, and symptom remission rate were observed between the two groups. The rates of cyst recurrence and secondary surgery in the single-stoma group were higher than those in the multiple-stoma group, although the difference was not significant. Endoscopic fenestration is an effective and minimally invasive approach for treating Galassi type III MCFACs. Single- and multiple-stoma endoscopic fenestrations have the same curative effect.

Outcome of Initial 3 Years of Cranial Endoscopy at DG Khan Medical College and Teaching Hospital, Dera Ghazi Khan

With the evolution of surgical approaches, endoscopic skull base surgery has emerged as a suitable alternative to many other invasive methods. The aim of this study was to investigate the efficacy and outcome of cranial endoscopy in treating various neurosurgical intracranial pathologies in terms of procedural success and complications. This observational, prospective case series was conducted at the Department of Neurosurgery of DG Khan Medical College from November 2017 to October 2020. The study enrolled 74 patients with indications for cranial neuroendoscopy. Clinical examination was performed, and a detailed history of the disease was obtained. Follow-up was conducted in the outpatient department. The collected data were analyzed using statistical analysis software. Of 77 procedures performed, endoscopic third ventriculostomy, arachnoid cyst fenestration, septostomy, colloid cyst excision, endoscopic assisted ventricular catheter placement, and intraventricular tumor biopsy were performed in 53.3%, 18.2%, 10.4%, 7.8%, 6.5%, and 3.9% of patients. Aqueductal stenosis was identified as the most common cause of obstructive hydrocephalus. Seizures and cerebrospinal fluid leaks were the most commonly reported complications (12% and 8.1%, respectively). The observed mortality rate was 2.7%. Neuroendoscopic surgery has become safe and effective, as surgeon experience and learning have lowered the risk of complications, and offers a low-cost alternative intervention.

Microsurgical Fenestration of Intracranial Arachnoid Cysts: Volumetric Analysis and Clinical Outcome

Introduction: There is paucity of data regarding change in arachnoid cyst (AC) volume following surgery. This study aimed at investigating the clinical outcome of ACs and applying 2 volumetric methods for determination of their volume change post microsurgical fenestration. Methods: Twenty-one ACs in 20 patients that underwent microsurgical fenestration were analyzed using 2 volumetric methods; the modified McDonald equation and the picture archiving and communication (PAC) system-based method. Patients were followed up for 23 ± 40.3 months. Results: The majority of the patients (13 or 65%) were children. Preoperative symptoms in children were mainly seizures and less commonly headache. Of the 20 patients, 12 (60%) had complete resolution of their preoperative symptoms with 8 (40.0%) showing partial improvement. Volumetric studies showed a mean reduction in AC size of 73.7% in children and 64.4% in adults using the PAC system versus 67.9% in children and 70.5% in adults using the modified McDonald equation method. There was no correlation between the percentage decrease in AC volume post surgery and degree of symptom improvement (49.2 ± 34.3% in patients with complete vs. 60.9 ± 40.3% in patients with only partial resolution of symptoms, p = 0.57). Discussion/Conclusion: Microsurgical fenestration is an effective approach for ACs with an excellent clinical outcome apparent in the complete or partial improvement of symptoms in all patients. Volumetric estimates of ACs and their change following surgery are feasible using the modified McDonald or PAC system methods. However, there is no correlation between the percentage decrease in AC volume after surgery and degree of clinical improvement.

Epilepsy and cognitive deterioration as postoperative complications of the arachnoid cyst fenestration. Case report

Objective With the aim of contributing to the discussion on treatment of patients with arachnoid cysts (AC) and their neuropsychological functioning, we present the case of a patient who has undergone surgery of AC located in the left Sylvian fissure. Case description: The patient had no cognitive deficits and no seizures before the cyst’s fenestration. After the procedure, however, occurrences of seizures have been observed. Along with the concomitant epileptic seizures, aphasia and serious memory problems also developed. The initial pharmacological treatment of the seizures brought about unsatisfactory results. The treatment was therefore modified a number of times and ultimately, seizures were brought under control to some extent. Despite the varied efforts at neuropsychological rehabilitation, cognitive impairment was still persistent up to a year after the surgery. Conclusions: 1) While referring patients with AC for surgery, one should always consider both the positive outcomes and the unintended and deleterious consequences. A cyst fenestration could in some cases lead to epilepsy and cause neuropsychological symptoms such as anomic aphasia and cognitive deterioration with memory function impairment. 2) Neurological patients, especially the ones qualified for surgery, should always undergo neuropsychological examination. The lack of data from presurgical neuropsychological examination may impact further treatment of neurosurgical patients.

Letter to the Editor Regarding “Diagnosis of Ventriculoperitoneal Shunt Malfunction: A Practical Algorithm”

Arachnoid cysts are benign cerebrospinal fluid collection within a duplication of arachnoid membrane and, when found in the retrocerebellar site, they may be associated with tonsils herniation. This rare situation of coexisting retrocerebellar arachnoid cyst (AC) and Chiari malformation type 1 (CM-1) have been previously reported in few cases (10 patients) with syringomyelia and hydrocephalus described to be the most relevant issues. The aim of this paper is to describe 3 pediatric cases of this condition with a systematic review of the literature, underlining the importance of surgical management tailored to the pathogenic mechanism.A restrospective analysis of patients treated for coexisting CM-1 and ACs at the authors' institution has been carried out.A case of a 10-month-old baby with coexisting AC and CM-1 with tri-ventricular hydrocephalus treated with endoscopic third ventriculostomy, a case of a 1-year-old child with a huge retrocerebellar AC and CM-1 treated with a cysto-peritoneal shunt, and a case of a 15-year-old child with retrocerebellar AC causing symptomatic CM-1 treated with C0-C2 decompression, AC fenestration and duraplasty are described. A long-term follow-up is reported.Surgical management of coexisting ACs and CM-1 should not aim at the complete resolution of the cyst or of tonsil herniation, especially when pediatric patients are treated. Rather, the purpose of the neurosurgeon should be to understand the underlying pathogenic mechanism, and then restoring both the cerebrospinal fluid flow in the posterior fossa and the dynamic equilibrium between ventricles, cyst, and subarachnoid space.

Rare case of diffuse spinal arachnoiditis following a complicated vertebral artery dissection

Spinal arachnoiditis (SA) is an extremely rare and delayed complication of subarachnoid hemorrhage (SAH). Little is known about its underlying pathogenesis and subsequent clinical course. A middle-aged patient presented with the worst headache of her life and a grade 3 SAH of the basal-cisterns and posterior fossa was identified on Computed Tomography scans (CT). Angiography revealed a ruptured dissecting aneurysm of the left vertebral artery (VA-V4), as well as an unruptured left Anterior Cerebral Artery (ACA-A1) aneurysm. The VA aneurysm was treated with flow diversion. The patient re-ruptured the stented aneurysm, another telescoping pipeline was placed. The patient developed polymicrobial ventriculitis, and returned several months later complaining of paraparesis and left sided weakness. Magnetic Resonance Imaging (MRI) revealed diffuse thecal dural thickening from the cervicomedullary junction to the sacrum. Loculations, diffuse edema and cord compression were noticed along the inferior surface of the cerebellum, and the cervico-thoracic spine with a T4–T6 syrinx. The patient underwent a posterior (T4–T8) spinal fusion and (T5–T7) decompression with arachnoid-cyst fenestration and placement of a subarachnoid-pleural shunt. On latest follow-up, the patient is weaning off the thoraco-lumbosacral orthosis and ambulating with a cane. SA is often a complicated two-staged disease in which a “free interval phase” separates the initial inflammatory reaction (IIR) from the late adhesive phase. Posterior fossa bleeding, warranting prolonged surveillance, additional bleeding and ventriculitis might augment the risk and the severity of arachnoiditis.

Endoscopic treatment of middle fossa arachnoid cysts.

Endoscopic treatment of middle fossa arachnoid cysts is an alternative option to microsurgical fenestration and shunting procedures. The procedure is minimally invasive and obviates the morbidity of craniotomy and shunting. Operative charts and videos of patients undergoing endoscopic fenestration of middle fossa arachnoid cysts were retrieved from the senior author's database of endoscopic procedures and reviewed. Description of the surgical techniques was then formulated. Endoscopic fenestration of middle fossa arachnoid cysts entails communicating the cyst cavity to the basal cisterns via multiple fenestrations that should be made as large as possible with care to avoid injury of the juxtaposed neurovascular structures.

Pediatric intraventricular arachnoid cysts in the body of lateral ventricle: surgical outcome and its embryologic background.

The aim of this study is for the surgical treatment and outcome of the endoscopic fenestration of the arachnoid cyst located in the ventricular body to trigone in the pediatric population. Special concern was paid for the developmental origin of the intraventricular cysts estimated from the postoperative follow-up neuroimagings. Between July 2002 and June 2015, we performed endoscopic and partly CT/MRI navigated fenestrations of intraventricular arachnoid cysts located at the body to trigone of the lateral ventricle in ten pediatric patients aged 2months to 5years. Based on the long axis of the cyst, we have opted for two surgical approaches: anterior approach via burr hole at Kocher's point and posterior approach via burr hole at the posterior occipital region. Fenestration was performed based on the intraoperative findings, either ventriculocystostomy, ventriculocystoventriculostomy, or ventriculocystocisternostomy. Intraventricular arachnoid cysts located in the body-trigone region showed a favorable outcome after endoscopic fenestration. All of the cysts shrank postoperatively. Follow-up neuroimagings taken between 6 and 126months after surgery strongly suggested its relationship with the midline cisterns. Of our ten cases, eight were suggestive for originating from the velum interpositum cistern while two seemed to root from the quadrigeminal cistern. In the present study, we found that endoscopic fenestration of intraventricular arachnoid cysts in the body to trigone is a safe procedure with a satisfactory outcome. In our limited experience, there are two anatomic backgrounds; velum interpositum cistern and quadrigeminal cistern. Differentiation can be possible by neuroimagings, especially those obtained after surgery.

Supraorbital Keyhole Microsurgical Fenestration of Symptomatic Temporal Arachnoid Cysts in Children: Advantages and Limitations.

To investigate the impact of endoscope-assisted microsurgical fenestration on temporal arachnoid cysts, and to determine the advantages and limitations of the technique. Twenty-five children with symptomatic temporal arachnoid cysts were operated via eyebrow supraorbital keyhole microsurgical fenestration targeting the medial cyst wall. Preoperative magnetic resonance imaging (MRI) of the brain was done for all patients. Preoperative clinical presentation of the patients included headache (80%), nausea & vomiting (64%), drug resistant epilepsy (52%), macrocephaly (12%) papilledema (28%), motor weakness in the form of right-sided hemiparesis (12%) and cranial nerve palsy. Postoperative complete subsidence of headache was noted in 50%, while 20% remained unchanged. Drug resistant epilepsy improved in 69% of the patients. Postoperative MRI showed initial decrease in cyst volume as early as 3 months, only in a range of 5-12% volume reduction, and the late follow-up done at 6 and 18 months continued to show further reduction reported to be significant (p < 0.001). Transient subgaleal cerebrospinal fluid (CSF) collection was the most common complication (20%). Only 1 patient experienced CSF leak mandating cysto-peritoneal shunting. Conclusıon: Eyebrow supraorbital keyhole microsurgical fenestration for temporal arachnoid cysts can be performed with a fairly low risk of complications and yields a favorable improvement in clinical and neuroimaging outcomes.

Microsurgical fenestration and cystoperitoneal shunt through preauricular subtemporal keyhole craniotomy for the treatment of symptomatic middle fossa arachnoid cysts in children.

The optimal surgical treatment for symptomatic middle fossa arachnoid cyst is still controversial. The most leading therapeutic options include cyst shunting and fenestration (endoscopic, microsurgical). We present our experience on surgical treatments of arachnoid cysts. A retrospective data review of 16 children who underwent keyhole craniotomy for microsurgical fenestration and shunting of middle fossa arachnoid cysts between 1999 and 2012 was performed after institutional review board approval. The average patient age was 6.1 years. The average follow-up period was 36.5 months. There were ten male and six female patients in the series. Indications for surgery included intractable headaches (50%), increasing in cyst size (18.75%), and seizures (31.25%). All patient records were reviewed for their clinical presentation, classification, cyst resolution, symptom resolution, and cyst outcomes. After surgery, all patients underwent assessments of clinical and radiological improvement. Postoperative complications were observed in two cases: progressively resolving monoparesia in one case and resolving epileptic seizure with monotherapy in the other. All patients had a satisfactory clinical outcome, and in 87.5%, there was either a decrease in the size or a complete disappearance of the MFAC. Nevertheless, three (18.75%) of all patients needed shunt revision because of shunt dysfunction. Complication related to surgical technique was cerebrospinal fluid leak which spontaneously resolved in one patient. Microsurgical fenestration with keyhole craniotomy to provide passage between cysts to basal cisterns together with cystoperitoneal shunting during the same operation is still an effective and safe method in cases with symptomatic middle fossa arachnoid cysts in children.

Endoscopic Treatment of a Fourth Ventricle Arachnoid Cyst via the Third Ventricle

Arachnoid cysts within the fourth ventricle have rarely been reported in the literature. Different procedures have been performed to restore a normal cerebrospinal fluid dynamic or pressure, including shunting and partial or complete excision of the cyst by open microsurgery. Cerebrospinal fluid shunts give only partial improvement of symptoms and are prone to malfunctions. The microsurgical excision of the cyst seems to offer the best chance of success. We report the case of a fourth ventricle arachnoid cyst successfully treated with a complete endoscopic cerebral procedure via the third ventricle. Endoscopic fenestration of fourth ventricle arachnoid cysts may be considered an effective neurosurgical treatment.

Institutional experience of endoscopic suprasellar arachnoid cyst fenestration

Suprasellar arachnoid cysts can differ from other arachnoid cysts in several ways, making a separate analysis of these cysts worthwhile. Herein, we present the outcome and perform volumetric analysis of six children with suprasellar arachnoid cysts treated with endoscopic ventriculocystocisternostomy in order to evaluate the long-term outcomes. Operative and postoperative data were retrospectively reviewed for six patients harboring suprasellar arachnoid cysts. Imaging was then used to follow success of surgical intervention. Six patients with suprasellar arachnoid cysts underwent ventriculocystocisternostomy. Presenting symptoms were headaches in three patients, developmental delay in another, and an incidental finding in the remaining patients. All patients had enlarged lateral and third ventricles on initial imaging. Average age at presentation was 145.7 months (65.4-250.2). Follow-up was an average of 46.5 months (3-84). The average cyst size was 153.96 cm(3) (42.98-369.20) preoperatively and an average of 39.92 cm(3) (3.20-101.47) at follow-up. Based on our experience, suprasellar arachnoid cyst treatment with ventriculocystocisternostomy is an adequate surgical intervention. Suprasellar and third ventricular size does respond to the surgical intervention at long-term follow-up.