Lateral Suboccipital Craniotomy With C1-C2 Hemilaminectomies and C1-C3 Fusion for the Treatment of a C1-C2 Synovial Cyst Causing Spinal Cord Compression: 2-Dimensional Operative Video

Atlantoaxial synovial cysts are a rare cause of cervical myelopathy. Here we describe a case of a 26-yr-old woman who presented with progressively decreasing right arm and leg strength and associated gait imbalance. On examination, she had diffuse weakness in the right upper and lower extremities, a positive right-sided Hoffman sign, and clonus in the right lower extremity. Computed tomography demonstrated an os odontoideum and a retro-odontoid cyst. Magnetic resonance imaging demonstrated a T1 hypointense, T2 hyperintense, slightly rim-enhancing retro-odontoid cyst causing a marked narrowing of the spinal canal, with resultant flattening and leftward deviation of the spinal cord. The patient consented to undergo cyst fenestration via a right suboccipital craniotomy and right C1-C2 hemilaminectomies, along with a C1-C3 instrumented posterior spinal fusion. This approach was chosen because it allows for cyst fenestration and instrumentation of the hypermobile cervical spine within the same incision. After the dura was opened and the arachnoid was dissected, the cyst was visualized compressing the spinal cord. The cyst was fenestrated just inferior to the C1 nerve rootlets, resulting in immediate egress of a gelatinous content; thereafter, all accessible cyst wall portions were removed. Fusion was performed with lateral mass screws at C1 and C3 and pars screws at C2. Pathological analysis described the cyst content as reactive fibrovascular tissue with cholesterol deposition. There were no complications associated with the procedure, and the patient's right-sided weakness had nearly resolved by postoperative day 1. Patient consent was granted for publication.

Fenestration of intracranial neurenteric cyst: A case report

Background: Neurenteric cysts are rare congenital lesions of endodermal origin which result from the failure of the neurenteric canal to close during embryogenesis. The majority of neurenteric cysts occur in the spinal cord, though in rare instances can occur intracranially, typically in the posterior fossa anterior to the pontomedullary junction (80%) or in the supratentorial region adjacent to the frontal lobes (20%). Case Description: We present the case of a 75-year-old woman with an extra-axial cystic lesion centered in the premedullary cistern causing brainstem compression. The lesion was later histopathologically confirmed to be a neurenteric cyst. She presented initially with a 4-month history of worsening headache, dizziness, and unsteady gait. We performed a left retrosigmoid craniotomy for cyst fenestration/biopsy with the aid of operating microscope and stealth neuronavigation. Following the procedure, the patient recovered without complications or residual deficits. Conclusion: This case illustrates the successful fenestration of an intracranial neurenteric cyst with good clinical outcome. We present the pre- and post-operative imaging findings, a technical video of the procedure, histopathological confirmation, and a brief review of the relevant clinical literature on the topic.

Intracranial arachnoid cysts in an infant: A technical note on the innovative use of navigation and flexible endoscopy for cyst fenestration

Background: 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. Case Description: 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. Conclusion: 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.

Interhemispheric arachnoid cyst

Background: Interhemispheric arachnoid cysts are uncommon and typically associated with other midline neurodevelopmental disorders, such as complete or partial agenesis of the corpus callosum. Case Description: We report a case of a 27-year-old woman with worsening headache, memory deficit, and radiological progression of an interhemispheric arachnoid cyst. The treatment consisted of craniotomy for interhemispheric cyst fenestration into both the interhemispheric cistern and lateral ventricle. The postoperative course was unremarkable, with considerable clinical improvement and significant reduction in cyst size. Conclusion: We successfully treat a patient with an enlarging arachnoid cyst and associated progressive symptoms with microsurgical fenestration.

Multiloculated Hydrocephalus: Surgical Techniques

Objective: Hydrocephalus shunt remains as the most common treatment choice for nonobstructive hydrocephalus, but in some cases multiloculated hydrocephalus (MH) remains a difficult neurosurgical disease despite of the different therapeutic options available. In children with MH multiple shunt procedures combined with neuroendoscopy may be required.(1) The rationale for neuroendoscopy in such complex cysts and multiloculated hydrocephalus is also to open several compartments to the normal fluid-filled spaces, minimize the number of isolated/loculated CSF spaces, and decrease shunt dependency and the number of proximal shunt catheters.(2) In such cases our major objective is keep the children with one or no one shunt and with one normal intracranial pressure (ICP). Most patients with multiloculated hydrocephalus are infants with a severe disability who present with high intracranial pressure. Multiple shunting was a routine practice so far to normalize the intracranial pressure, but in these cases shunt complications could be quite common including shunt infection, malposition and malfunction which needed more shunt revision surgeries.(1, 3) Neuroendoscopy has changed the treatment options for complex multiloculated hydrocephalus. The possibility to do several fenestrations and change multiples cysts in one simple cyst or ventricle was one important improvement in MH treatment.(4-6) In this review we will discuss aspects related to etiology, surgical techniques, and results in multiloculated hydrocephalus. Methods: The authors carried out a literature review on multiloculated hydrocephalus and evaluated a series of personal cases operated in the recent years. The keywords loculated hydrocephalus and surgical technique were used in Pubmed database website. Fifty-two articles were obtained and reviewed. From these publications we select the most relevant ones for the presentation. The articles were divided according to the main subject, with articles on etiology, surgical techniques and outcomes were selected. We also reviewed some difficult cases with MH from personal experience. In all of those cases endoscopy procedures were performed associated to shunt procedures in all cases. The authors described some different techniques of cyst fenestration and the association to shunt or not. Results/Discussion: Neuroendoscopy has changed the treatment in MH. This is a very difficult and interesting disease. Common risk factors for the development of MH include intraventricular hemorrhage, bacterial meningitis, shunt infection, and cerebrospinal fluid (CSF) overdrainage from shunt placement (rare). The magnetic resonance imaging (MRI) or computerized tomography (CT) scan with evidence of septations causing marked nonuniform compartmentalization and enlargement within the ventricular system are the most important ways to do the diagnosis of MH. Predisposing factors include low birth weight, prematurity, perinatal complications, and congenital malformation. Although the full pathogenesis of MLH remains unclear, it is known that inflammation leads to subependymal gliosis, which produces glial tufts and septations that occlude the normal ventricle system. Septations also develop via organization of intraventricular exudate and debris from ventriculitis. Despite os clinical history of poor outcome, head circuference increase and prior infection or brain bleeding, we need image to perform the diagnosis. Types of loculated hydrocephalus could be divided in: multiloculated and uniloculated. The most important classification was done by Spennato.(5) He divided in five types: 1) hydrocephalus with multiple intraventricular septations; 2) isolated lateral ventricle/unilateral hydrocephalus; 3) entrapped temporal horn; 4) isolated fourth ventricle; 5) expanding cavum septi pellucidi/cavum vergae Using the endoscope to treat MH has some advantages.(7, 8) This is a less invasiveness and this is very important in kids.(6) Avoidance of brain retraction, less blood loss, faster operation time, and shorter hospital stay. But endoscopy has some risk and possible complications. It also has several disadvantages. A subdural hematoma and/or hygroma may form, but the incidence of this is lower than with open craniotomy. The risk of ventriculitis, CSF leakage (subcutaneous CSF collection), and hemorrhage are reported to be like that with open craniotomy. Intraoperative bleeding can usually be easily managed by irrigation or coagulation. However, handling of significant intraoperative bleeding is not as easy in endoscopy as in open craniotomy.(9) Some new technologies could improve the outcome and avoid risk and complications.(10, 11) Navigation could be used in two forms: Navigation system is used to planning the entry point and the endoscopy trajectory Endoscopy guided and navigation during all surgical time. The evaluation of results is presented in different ways in the literature. The main outcomes observde for measuring results were: hydrocephalus control or not, number of surgery performed and number of catheters used.(4) Shunt Independence is rare. Conclusion: Multiloculated hydrocephalus is one difficult disease to treat.(4) Neuroendoscopy cyst fenestration was one great improvement in treatment of MH, but after this new procedure the clinical outcome still no so good. Endoscopy is important to decrease the number of shunts and surgeries.

Endoscopic endonasal cyst fenestration into the sphenoid sinus using the mucosa coupling method for symptomatic Rathke’s cleft cyst: a novel method for maintaining cyst drainage to prevent recurrence

OBJECTIVERathke’s cleft cyst (RCC) is a benign cystic lesion with a relatively high incidence of local recurrence that occasionally requires repeat surgery. To prevent recurrence, simple cyst fenestration and drainage of the cyst contents to the sphenoid sinus is recommended, but it occasionally recurs. The authors postulated that obstruction of fenestration is a main cause of recurrence, and they developed a method, named the “mucosa coupling method (MC method),” that maintains persistent drainage. In this method, the RCC epithelium and the mucosa of the sphenoid sinus are connected, which promotes re-epithelialization between the two epithelia, maintaining persistent drainage. The outcome of this method was compared with that of conventional cyst fenestration.METHODSIn a consecutive series of 40 patients with RCC, the surgical strategy was changed during the study period: from December 2009 to September 2014 (the conventional period), 24 patients were scheduled to be treated using the conventional fenestration method, whereas from September 2014 to September 2017 (the MC period), 16 patients were scheduled to be treated using the MC method. However, because of an intraoperative CSF leak, the fenestration was closed during surgery in 3 patients in the conventional period and 2 in the MC period; therefore, these 5 patients were excluded from the analysis. Twenty-one patients treated with the conventional fenestration method (conventional group) and 14 patients treated with the MC method (MC group) were analyzed. All patients regularly underwent MRI after surgery to detect reaccumulation of cyst contents. The rate of reaccumulation with and without reoperation, visual outcomes, endocrinological outcomes, and postoperative complications were compared between these two groups.RESULTSThe median follow-up period in all 35 patients was 48.0 months (range 1–96 months), 54.0 months (range 1–96 months) in the conventional group and 35.5 months (range 12–51 months) in the MC group. No reaccumulation was detected on MRI in the 14 patients in the MC group, whereas it was noted in 9 (42.9%) of 21 patients in the conventional group, and 2 of these 9 patients required repeat surgery. There were no significant differences in visual and endocrinological outcomes and complications between these two groups.CONCLUSIONSThe MC method for RCC is effective for preventing obstruction of cyst fenestration, which contributes to preventing cyst reaccumulation. Furthermore, this method is equivalent to the conventional fenestration method in terms of visual and endocrinological outcomes and the complication rate.