Explore the vast range of titles available.

The arachnoid barrier delineates the border between the central nervous system and dura mater. Although the arachnoid barrier creates a partition, communication between the central nervous system and the dura mater is crucial for waste clearance and immune surveillance 1 , 2 . How the arachnoid barrier balances separation and communication is poorly understood. Here, using transcriptomic data, we developed transgenic mice to examine specific anatomical structures that function as routes across the arachnoid barrier. Bridging veins create discontinuities where they cross the arachnoid barrier, forming structures that we termed arachnoid cuff exit (ACE) points. The openings that ACE points create allow the exchange of fluids and molecules between the subarachnoid space and the dura, enabling the drainage of cerebrospinal fluid and limited entry of molecules from the dura to the subarachnoid space. In healthy human volunteers, magnetic resonance imaging tracers transit along bridging veins in a similar manner to access the subarachnoid space. Notably, in neuroinflammatory conditions such as experimental autoimmune encephalomyelitis, ACE points also enable cellular trafficking, representing a route for immune cells to directly enter the subarachnoid space from the dura mater. Collectively, our results indicate that ACE points are a critical part of the anatomy of neuroimmune communication in both mice and humans that link the central nervous system with the dura and its immunological diversity and waste clearance systems. Arachnoid cuff exit points create openings in the arachnoid barrier enabling the drainage of cerebrospinal fluid and exchange of molecules and cells between the dura and the subarachnoid space, therefore physically connecting the brain and the dura.

Objective Spinal extradural arachnoid cysts (SEDC) are rare primary spinal lesions, accounting for less than 1% of all spinal epidural lesions. The literature contains only case reports of this pathology, and treatment remains controversial due to its rarity. Major reported SEDC cases are caused by leaking out of cerebrospinal fluid through a dural defect in the thecal sac forming an extradural cyst. Other reports describe non-communicating SEDC cases where the dural defect was not identified. We report a literature review on SEDC and the case of a 53 year‑old female who presented with type IA extradural cyst with subarachnoid space communication. Methods Literature review, preoperative imaging and surgical technique. Results The extradural cyst was excised completely and the dural defect was repaired. After surgical decompression, neurological symptoms gradually recovered. Conclusions The extradural arachnoid cyst is an uncommon entity. Preoperative imaging is one of the determining elements in orienting the therapeutic management of the SEDCs. The choice of the surgical technique must be the least invasive in order to avoid postoperative complications. Subtotal or complete excision of the cyst, followed by obliteration of the communication stalk and repair of the dural defect is the gold standard treatment.

Background Spinal arachnoid cysts (SAC) and spinal arachnoid webs (SAW) are intradural pathologies, often presenting with pain and/or myelopathic symptoms. Reports on postoperative outcomes for SAC and SAW are scarce. This study aims to assess the surgical outcomes of SAC and SAW. Methods Patients who underwent surgical treatment for SAC or SAW at our institution between 2011 and 2023 were retrospectively reviewed. Demographic data, radiological findings, surgical management, and clinical outcomes were evaluated using the modified McCormick (mMC) scale. Outcomes were categorized as \"favorable\" (mMC I-II) or \"unfavorable\" (mMC III-V). Results A total of 35 patients (29 SAC, 6 SAW) were analyzed. Mean age was 50.9 (SD ± 9.8) years. Males comprised 70.3% of cases (SAC: 64.5%, SAW: 100%). Most common symptoms were local or radiating pain (SAC 77.4%; SAW 100%), gait-disturbance (SAC 45.2%; SAW 16.7%), sensory-deficits (SAC 32.3%; SAW 66.7%) and impaired motor function (SAC 20%; SAW 16.7%). Median preoperative mMC was 2 in both groups (SAC IQR: 1; SAW IQR: 1). Median postoperative mMC was 1 in both groups (SAC CI 1.07–1.34; SAW CI 0.74–1.60). Favorable outcome (postoperative mMC I-II) was achieved in 26 SAC patients (90%) and 5 SAW patients (83%) respectively. Surgical complications occurred in 14.7%, all in the SAC group, without lasting deficits. Conclusion Surgical treatment for SAC and SAW appears to have an overall favorable outcome, though larger cohort analyses are needed. Surgery should be considered in symptomatic patients.

A quadrigeminal cistern arachnoid cyst is an extremely rare cause of trigeminal neuralgia in adulthood. This report presents the fourth case in the literature of trigeminal neuralgia caused by a giant quadrigeminal cistern arachnoid cyst. A 52-year- old woman presented with a 3-month history of cerebellar ataxia and vertigo. She had a 2-year history of trigeminal neuralgia that was unresponsive to medical therapy. Neuroimaging studies revealed a cystic lesion in the quadrigeminal cistern associated with hydrocephalic enlargement. Using an infratentorial supracerebellar approach, neuroendoscope-assisted decompression and fenestration of the cyst were performed. Postoperatively, the patient was pain-free and able to walk unaided without symptoms of ataxia. Keywords: Arachnoid cyst; ataxia; hydrocephalus; quadrigeminal cistern; trigeminal neuralgia.

Background Spinal epidural arachnoid cysts (SEACs) are rare, non-neoplastic pathologies that can cause compressive myelopathy. Preoperative identification of the exact fistula location is crucial for minimally invasive management. Methods This single-center retrospective study included 27 patients with SEACs who underwent “double-needle puncture myelography” to precisely localize the fistula before minimally invasive surgery. Clinical presentations, radiological findings, and surgical outcomes were analyzed. Results Among the 27 patients, the most common clinical complaint was sensory dysfunction (14 patients, 51.9%). Motor dysfunction, manifested as lower limb weakness, was observed in 11 patients (40.7%), while 2 patients were asymptomatic at admission. Consistency analysis between radiographic localization and intraoperative findings demonstrated that the “double-needle puncture myelography” technique accurately identified the surgical segments and laterality of all fistulas except for one patient, who required repeat radiographic localization. Minimally invasive approaches, including hemilaminectomy or mini-hemilaminectomy, were successfully performed in 26 patients (96.3%) for fistula exposure. Conclusions The “double-needle puncture myelography” technique allows for the swift acquisition of precise anteroposterior and lateral projection dynamic X-ray images during the procedure. As a valuable preoperative diagnostic tool, it accurately pinpoints the location of the fistula, thereby minimizing surgical trauma and preserving spinal stability.

PurposeIntrasellar arachnoid cysts are extremely rare, and their differentiation from other cystic lesions can be challenging because of their similar imaging characteristics.MethodsThis study aimed to describe the imaging characteristics observed in five patients and correlate them with developmental and growth mechanisms.ResultsThese cysts are characterized by the lack of contrast enhancement in their walls and posterior displacement of the pituitary gland. As a result, no enhancing tissue is present at the anterior portion of the sella where it interfaces with the sphenoid sinus.ConclusionWe believe that this sign will lead to more accurate diagnosis and improve surgical planning.

Purpose 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. Conclusion 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.

Introduction Multiple synchronous spinal extradural arachnoid cysts are extremely rare in children and can lead to cord compression and disability. Multiple spinal extradural arachnoid cysts (SEDACs) in children with immature and growing spine need to be studied separately from multiple SEDACs in adults with mature and fully grown spine because of multiple surgical limitations in children (blood loss, surgery duration, long-term spinal stability after long segment exposure, etc.). Material and methods We planned a non-systematic literature review of similar cases described in literature to analyse the pattern of presentation, management, and outcome of this surgically curable disease. Results A total of 28 cases of paediatric multiple SEDACs in the age range of 5 months to 17 years and mean age of 11.54 years were analysed. Exposure was achieved by laminectomy in 9, laminoplastic laminotomy in 13, laminectomy in first surgery followed by laminoplasty in second surgery (re-exploration) in 1, hemilaminectomy in 2, and technique “not reported” in 3 children. Complete/near-complete recovery was seen in 27 (96.42%) children. Postoperative spine deformity was reported in 7 (25%) children and was progressive in 2 children during serial follow-up. Conclusions Symptomatic multiple synchronous SEDACs in children is a rare surgically curable condition. Sincere attempt to find out a dural defect in all cysts is a very important step in multiple SEDAC surgery. Total cyst wall excision with closure of all dural defects is the gold standard treatment for symptomatic cases. Laminoplasty is preferred for excision of multiple SEDACs in children to prevent postoperative spine deformity during long-term follow-up. Long serial follow-up for postoperative spine deformity is necessary.

Objective The best treatment strategies for cerebral arachnoid cysts (CAC) are still up for debate. In this study, we present CAC management, outcome data, and risk factors for recurrence after surgical treatment, focusing on microscopic/endoscopic approaches as compared to minimally invasive stereotactic procedures in children and adults. Methods In our single-institution retrospective database, we identified all patients treated surgically for newly diagnosed CAC between 2000 and 2022. Microscopic/endoscopic surgery (ME) aimed for safe cyst wall fenestration. Stereotactic implantation of an internal shunt catheter (STX) to drain CAC into the ventricles and/or cisterns was used as an alternative procedure in patients aged ≥ 3 years. Treatment decisions in favor of ME vs. STX were made by interdisciplinary consensus. The primary study endpoint was time to CAC recurrence (TTR). Secondary endpoints were outcome metrics including clinical symptoms and MR-morphological analyses. Data analysis included subdivision of the total cohort into three distinct age groups (AG1, < 6 years; AG2, 6–18 years; AG3, ≥ 18 years). Results Sixty-two patients (median age 26.5 years, range 0–82 years) were analyzed. AG1 included 15, AG2 10, and AG3 37 patients, respectively. The main presenting symptoms were headache and vertigo. In AG1 hygromas, an increase in head circumference and thinning of cranial calvaria were most frequent. Thirty-five patients underwent ME and 27 STX, respectively; frequency did not differ between AGs. There were two (22.2%) periprocedural venous complications in infants (4- and 10-month-old) during an attempt at prepontine fenestration of a complex CAC, one with fatal outcome in a 10-month-old boy. Other complications included postoperative bleeding (2, 22.2%), CSF leaks (4, 44.4%), and meningitis (1, 11.1%). Overall, clinical improvement and significant volume reduction ( p  = 0.008) were seen in all other patients; this did not differ between AGs. Median follow-up for all patients was 25.4 months (range, 3.1–87.1 months). Recurrent cysts were seen in 16.1%, independent of surgical procedure used ( p  = 0.7). In cases of recurrence, TTR was 7.9 ± 12.7 months. Preoperative ventricular expansion ( p  = 0.03), paresis ( p  = 0.008), and age under 6 years ( p  = 0.03) were significant risk factors for CAC recurrence in multivariate analysis. Conclusions In patients suffering from CAC, both ME and STX can improve clinical symptoms at low procedural risk, with equal extent of CAC volume reduction. However, in infants and young children, CAC are more often associated with severe clinical symptoms, stereotactic procedures have limited use, and microsurgery in the posterior fossa may bear the risk of severe venous bleeding.

Background Arachnoid cysts are extra parenchymal, intra-arachnoid fluid collections of unknown origin, similar in content to cerebrospinal fluid. Suprasellar arachnoid cysts are a rarer localization resulting from abnormalities of the Liliequist membrane or cystic dilatation of the interpeduncular cisterna. We aimed to contribute to the literature by presenting a series of suprasellar arachnoid cyst cases with endoscopic intervention and long-term results. Methods This study analyzed radiographic data, clinical symptoms, surgical records, and videos of giant arachnoid cysts that underwent endoscopic surgery between 2013 and 2023. Cyst volumes and Evan’s indexes were calculated both preoperatively and postoperatively. Results The patient population consisted of 3 males (21.4%, 3/14 patients) and 11 females (78.5%, 11/14 patients). Their age at the time of surgery ranged from 1 year to 56 years (mean: 14.4 years). Of the total 14 patients, 4 (28.5%, 4/14 patients) were adults (age ≥ 18 years), and 10 (71.4%, 10/14 patients) were pediatric (age < 18 years). The most common presenting complaints were gait disturbance (21.4%, 3/14 patients), headache (21.4%, 3/14 patients), increased head circumference (14.2%, 2/14 patients), hormonal disorders (14.2%, 2/14 patients), seizures (14.2%, 2/14 patients), and forgetfulness (7.1%, 1/14 patients). Ventriculocystocisternostomy was performed in all patients. The most common perioperative complication was bleeding controlled by irrigation (28.5%, 4/14 patients). The mean follow-up period was 63.8 months (min:12 months-max:125 months). In the postoperative long-term follow-up, the preoperative neurologic examinations of the patients showed complete recovery, and hormonal problems returned to normal. Conclusions Endoscopic options for the surgery of rare giant suprasellar arachnoid cysts, especially ventriculocisternostomy, are safe, less invasive, and successful, with fewer recurrences and the need for a second operation in the long-term results of patients who underwent ventriculocisternostomy according to our experience.