OBJECTIVE: Children diagnosed with suprasellar arachnoid cysts often concurrently have hydrocephalus. This study aims to classify the relationship between suprasellar arachnoid cysts and hydrocephalus, discussing surgical strategies-shunting or neuroendoscopic approaches-and their sequence, based on this classification.
METHODS: A retrospective analysis was conducted on 14 patients diagnosed with suprasellar arachnoid cysts and hydrocephalus, treated surgically by the first author between January 2016 and December 2020. Clinical features, radiological findings, surgical strategies, and outcomes were reviewed. The classification of the relationship between the suprasellar arachnoid cysts and hydrocephalus was developed and illustrated with specific cases. Recommendations for future surgical management based on this classification are provided.
RESULTS: We classified the relationship between suprasellar arachnoid cysts and hydrocephalus into three categories. SACH-R1, the direct type, represents cases where the cysts cause obstructive hydrocephalus. Here, neuroendoscopic ventriculocystocisternostomy (VCC) effectively treats both conditions. SACH-R2, the juxtaposed type, involves concurrent occurrences of cysts and hydrocephalus without a causative link. This is further subdivided into SACH-R2a, where acute progressive communicating hydrocephalus coexists with the cyst, initially managed with a ventriculoperitoneal shunt, followed by VCC upon stabilization of hydrocephalus; and SACH-R2b, where the cyst coexists with chronic stable communicating hydrocephalus, first addressed with VCC, followed by monitoring and potential secondary shunting if needed. Key factors differentiating SACH-R2a from SACH-R2b include the patient\'s age, imaging signs of fourth ventricle and cisterna magna enlargement, and the rapid progression or chronic stability and severity of hydrocephalus symptoms. SACH-R3, the reverse type, describes scenarios where shunting for hydrocephalus leads to the development or enlargement of the cyst, managed via neuroendoscopic VCC with precautions to prevent infections in existing shunt systems.
CONCLUSIONS: The simultaneous presence of suprasellar arachnoid cysts and hydrocephalus requires a nuanced understanding of their complex relationship for optimal surgical intervention. The analysis and classification of their relationship are crucial for determining appropriate surgical approaches, including the choice and sequence of shunting and neuroendoscopic techniques. Treatment should be tailored to the specific type identified, rather than blindly opting for neuroendoscopy. Particularly for SACH-R2a cases, we recommend initial ventriculoperitoneal shunting.

BACKGROUND: Suprasellar Arachnoid Cysts (SAC) are rare heterogeneous entities. Though prenatally diagnosed, they are rarely treated pre-birth. Symptomatic cases are mainly seen in infants.
METHODS: We describe a case of a prenatally symptomatic suprasellar arachnoid cyst treated postnatally. The cyst was diagnosed on a routine ultrasound at 22 weeks, was rapidly evolving in the ultrasounds and the MRI of the 29th week. It then became symptomatic at 30 weeks with episodes of fetal bradycardia, independent to the uterine contractions. Antenatal treatment was discussed but delivery decided in emergency despite the prematurity via C-section. Though well tolerated postnatally, the cyst continued to grow. Endoscopic ventriculo-cysto-cisternostomy was performed on the 5th day of birth. Despite progressive reduction of the cyst, residual brainstem compression and evolving ventriculomegaly lead to a transient extrathecal internal shunting.
CONCLUSIONS: Our case suggests that prenatally diagnosed cysts require a close follow-up. Treatment options and timing should be adapted to anatomy, cyst evolution and symptoms whether it is before or after birth.

Suprasellar arachnoid cysts represent a rare occurrence in the pediatric population and usually cause symptoms related to mass effect and can occasionally cause endocrine dysfunctions. The association between SAC and the syndrome of inappropriate antidiuretic hormone (SIADH) in the pediatric population has rarely been described previously. In most cases, SIADH is temporary and resolves by treating the underlying cause. The first-line treatment consists of fluid restriction in asymptomatic children. Oral urea and demeclocycline are other effective treatment options. Vaptans are a new class of medication for the management of SIADH. These agents are a nonpeptide vasopressin V2 receptor antagonist that selectively antagonizes the antidiuretic effect of AVP, resulting in excretion of diluted urine or \"aquaresis.\" Their efficacy has been shown in adult patients with euvolemic or hypervolemic hyponatremia. However, evidence is lacking in pediatric patients with SIADH. We report the case of a 9-year-old female child with a SAC, who underwent endoscopic fenestration at the age of 2 years. After surgery she developed chronic hyponatremia due to SIADH. Hyponatremia was refractory to treatment with fluid restriction, oral sodium, and urea. In order to normalize serum sodium levels, tolvaptan treatment was started on a compassionate-use basis; 24-48 h later serum sodium levels returned to normal. To date, tolvaptan has been used regularly for 6 years with no side effects occurring during the treatment period. This is the first case of a child with chronic SIADH secondary to SAC successfully treated with tolvaptan. Further studies are needed to demonstrate its usefulness on a broader case series.

Suprasellar arachnoid cysts are a rare but important pediatric neurosurgical pathology with unknown ideal management. They have been previously managed with techniques including open craniotomy with microsurgical fenestration, cystoperitoneal shunting, endoscopic ventriculocystostomy, and endoscopic ventriculocystocisternostomy (VCC), without a consistent consensus on the best surgical approach. We present an overview of the literature on surgical management of suprasellar arachnoid cysts.
A literature search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was conducted for all articles evaluating treatment modalities for suprasellar arachnoid cysts, using PubMed, OVID, and Web of Science.
Twenty-five articles on management of suprasellar arachnoid cysts in children were identified. Few published studies exist that examine different types of surgical management across a single institution. The majority of studies reported best clinical outcomes in patients treated with endoscopic approaches when compared with microsurgical fenestration or cystoperitoneal shunting, reporting lower rates of infection, shunt dependence, and need for revision in addition to better resolution of clinical symptoms. Furthermore, most studies argue that VCC is superior to ventriculocystostomy, offering better long-term improvement of clinical symptoms and lower rates of failure.
This study examines the current literature on suprasellar arachnoid cyst surgical management to conclude that an endoscopic approach in comparison with other approaches has the best outcomes. Of the endoscopic options available, VCC provides patients with the best long-term resolution of symptoms and the lowest need for revision. These findings should be further investigated with larger multicenter studies to further compare different surgical techniques and outcomes.

To investigate the effectiveness of endoscopic fenestration in the patients with prior failed ventriculoperitoneal (VP) shunt treatment of suprasellar arachnoid cysts (SACs). Between 2012 and 2018, four pediatric patients of SACs with previous failed VP shunt treatment were surgically treated using endoscopic ventriculocystocisternostomy (VCC) in our hospital. The clinical symptoms, imaging data, and surgical outcomes were collected and analyzed retrospectively. A literature review is provided with regard to the reasons of shunt failure and surgical outcome of further endoscopic fenestration in the previously reported patients of SACs with prior failed VP shunt. For the 4 cases, the initial clinical symptoms relieved or even disappeared after shunt placement, but, respectively, recurred 2, 6, 11, and 6 months later. MR scans were conducted when the clinical symptoms reappeared and showed a cyst had greatly enlarged after shunt placement. Furthermore, VP shunt-related slit ventricle was also demonstrated in 3 cases. Clinical improvement and cysts shrinkage occurred in all 4 patients after VCC. Slit ventricle and hydrocephalus were also resolved. Three patients had their shunt apparatus removed after VCC, and another patient\'s guardian refused to remove the shunt apparatus. Subdural hematoma occurred in one case after shunt apparatus removal. Four patients have been stable during follow-up period (mean follow-up 26.5 months). All the three patients whose VP shunt were removed were shunt independence. There were 24 patients who underwent endoscopic fenestration as an alternative to the failed VP shunt treatment in the published reports. Added our 4 patients to the published group, the effective rate of endoscopic fenestration for SACs following previous failed VP shunt treatment was approximately 93% (26/28). Of the 24 patients, the shunt apparatuses were in situ or reimplantation in 9 patients due to shunt dependence. The correction to recognize the SAC is the first condition to select the optimal management philosophy. The analysis of the series suggests endoscopic operation is still an effective and safe option in the SAC patients with previous failed VP shunt, and the shunt apparatus can be removed for some patients. The short interval time between shunt operation and endoscopic fenestration is conductive to return patients to the shunt-free state.