Closure Of Cerebrospinal Fluid Leaks Research Articles

Surgical closure of spinal cerebrospinal fluid leaks improves symptoms in patients with superficial siderosis.

Spinal cerebrospinal fluid (CSF) leaks may cause a myriad of symptoms, most common being orthostatic headache. In addition, ventral spinal CSF leaks are a possible etiology of superficial siderosis (SS), a rare condition characterized by hemosiderin deposits in the central nervous system (CNS). The classical presentation of SS involves ataxia, bilateral hearing loss, and myelopathy. Unfortunately, treatment options are scarce. This study was undertaken to evaluate whether microsurgical closure of CSF leaks can prevent further clinical deterioration or improve symptoms of SS. This cohort study was conducted using data from a prospectively maintained database in two large spontaneous intracranial hypotension (SIH) referral centers in Germany and Switzerland of patients who meet the modified International Classification of Headache Disorders, 3rd edition criteria for SIH. Patients with spinal CSF leaks were screened for the presence of idiopathic infratentorial symmetric SS of the CNS. Twelve patients were included. The median latency between the onset of orthostatic headaches and symptoms attributed to SS was 9.5 years. After surgical closure of the underlying spinal CSF leak, symptoms attributed to SS improved in seven patients and remained stable in three. Patients who presented within 1 year after the onset of SS symptoms improved, but those who presented in 8-12 years did not improve. We could show a significant association between patients with spinal longitudinal extrathecal collections and SS. Long-standing untreated ventral spinal CSF leaks can lead to SS of the CNS, and microsurgical sealing of spinal CSF leaks might stop progression and improve symptoms in patients with SS in a time-dependent manner.

Recurrent bacterial meningitis with cerebrospinal fluid rhinorrhea

Introduction: Recurrent bacterial meningitis is a rare clinical phenomenon, but a telltale sign of a mysterious foe. It is an occurrence of two or more episodes of bacterial meningitis by different organisms, or with the same organism and the episodes separated by an interval of at least three weeks. Case Report: We present a case of a 29-year-old gentleman who presented with acute pyogenic meningitis due to Streptococcus pneumoniae. This is the second episode of confirmed bacterial meningitis in two years with another episode of meningitis ten years ago, which was treated as tuberculous. History of rhinorrhea was elicited on direct questioning and cerebrospinal fluid leak through cribriform plate was confirmed on magnetic resonance imaging. The current episode of meningitis was successfully treated with intravenous high dose cephalosporin and short course dexamethasone. The patient was referred to a neurosurgeon for closure of cerebrospinal fluid leak. Conclusion: This case highlights the importance of a thorough clinical history and awareness of a seemingly unimportant symptom which can be an important diagnostic clue.

351 Anterior Ethmoid Artery Septal Flap for Endoscopic Reconstruction of Frontal Sinus CSF Leak

Abstract Introduction Anterior skull base cerebrospinal fluid (CSF) leaks are managed successfully with endonasal surgery. Endoscopic closure of CSF leaks from posterior table of the frontal sinus remains challenging. Vascularized Hadad-Bassagasteguy flap (HBF) reconstruction of the skull base has increased CSF closure rates but does not extend to frontal sinus. We describe our technique using septal flap pedicled by anterior ethmoid artery (AEA) for repairing frontal defects. Method Retrospective review of cases of frontal CSF leak repair using the AEA flap reconstruction. Flap design: an anterior vertical septal mucosa incision at posterior border of the frontal sinusotomy is made and extended to nasal floor. Posterior vertical incision is made 1 cm posterior to the projection of the axilla of the middle turbinate on the septum and extended to nasal floor. A horizontal incision along the nasal floor joins the two incisions. The flap is raised and rotated into the frontal sinus over the posterior table reconstructed defect. Results Three patients identified. Two males, one female, aged 11, 33 and 56. Patient histories included recurrent bacterial meningitis following head trauma, recurrent sinusitis and fronto-ethmoidal osteoma, with intraoperative CSF leak and CSF rhinorrhea due to meningoencephalocele. The three posterior wall defects were successfully repaired endoscopically with multilayer reconstruction and the AEA septal flap. Conclusions The anterior ethmoid artery septal flap can be successfully utilised for frontal CSF leak repair. Flap is conveniently located for frontal sinus defects. When the septum is intact it provides an excellent final layer as part of multilayer reconstruction.

Sensorineural Hearing Loss Caused by Labyrinthine Erosion Due to a Cerebrospinal Fluid Diverticulum

To present a case of progressive sensorineural hearing loss (SNHL) caused by labyrinthine erosion secondary to expanding geniculate ganglion cerebrospinal fluid (CSF) diverticulum extending along the path of the facial nerve. Thirteen-year-old man with no past medical history or risk factors presented with unilateral progressive SNHL and no other otologic or neurologic symptoms. Audiological data as well as imaging studies including a magnetic resonance imaging (MRI) of the brain and internal auditory canal and a temporal bone computed tomography (CT) are presented. Partial labyrinthectomy, CSF leak closure, and cochlear implantation were performed. A lumbar puncture was obtained 2 months postoperatively. Closure of the CSF leak. Mastoidectomy revealed a wide area of CSF leak through the geniculate ganglion and fallopian canal with partial destruction of the superior and lateral semicircular canals by an expanding diverticulum. This is an unusual presentation of progressive SNHL due to partial labyrinthine erosion due to a meningocele of the geniculate ganglion along the fallopian canal. It is likely that the patient had a congenital open pathway through the labyrinthine segment of the facial nerve and CSF pulsations created the meningocele over a few years. This case argues for early closure of such CSF diverticula to prevent possible SNHL due to labyrinthine erosion.

Simulation of Cerebrospinal Fluid Leak Repair Using a 3-Dimensional Printed Model.

Acquiring proficiency for the repair of a cerebrospinal fluid (CSF) leak is challenging in great part due to its relative rarity, which offers a finite number of training opportunities. The purpose of this study was to evaluates the use of a 3-dimensional (3D) printed, anatomically accurate model to simulate CSF leak closure. Volunteer participants completed two simulation sessions. Questionnaires to assess their professional qualifications and a standardized 5-point Likert scale to estimate the level of confidence, were completed before and after each session. Participants were also queried on the overall educational utility of the simulation. Thirteen otolaryngologists and 11 neurosurgeons, met the inclusion criteria. A successful repair of the CSF leak was achieved by 20/24 (83.33%), and 24/24 (100%) during the first and second simulation sessions respectively (average time 04:04 ± 1.39 and 02:10 ± 01:11). Time-to-close-the-CSF-leak during the second session was significantly shorter than the first (p < 0.001). Confidence scores increased across the training sessions (3.3 ± 1.0, before the simulation, 3.7 ± 0.6 after the first simulation, and 4.2 ± 0.4 after the second simulation; p < 0.001). All participants reported an increase in confidence and believed that the model represented a valuable training tool. Despite significant differences with varying clinical scenarios, 3D printed models for cerebrospinal leak repair offer a feasible simulation for the training of residents and novice surgeons outside the constrictions of a clinical environment.

Use of Acetazolamide in the Postoperative Care of Endoscopic Cerebrospinal Fluid Leak Closure

Spontaneous cerebrospinal fluid (CSF) leaks are defined as leaks without identifiable etiology, often presenting as spontaneous rhinorrhea. This is thought to be a variant of idiopathic intracranial hypertension (IIH). Spontaneous CSF leak closure often requires surgery, which has proven to be less successful than their non-spontaneous counterparts. There is growing evidence that active intracranial pressure (ICP) management in the postoperative care can improve success rates. We aim to give an update about the current use of acetazolamide in the postoperative care of spontaneous CSF leak closure.

Management of coexistent sinonasal pathology in patients undergoing endoscopic cerebrospinal fluid rhinorrhea repair

IntroductionPatients who undergo endoscopic cerebrospinal fluid rhinorrhea repair may occasionally present with coexistent sinonasal pathology which may or may not need to be addressed prior to surgical repair. Some patients may develop new onset nasal morbidity related to endoscopic repair. ObjectiveTo study the prevalence and management of additional sinonasal pathology in patients who undergo endoscopic repair of cerebrospinal fluid rhinorrhea MethodsA retrospective review of patients who underwent endoscopic cerebrospinal fluid leak repair was conducted to note the presence of coexistent sinonasal morbidity preoperatively and in the followup period. ResultsOf a total of 153 patients who underwent endoscopic closure of cerebrospinal fluid leak, 97 (63.4%) were female and 56 (36.6%) males. Most patients (90.2%) were aged between 21 and 60 years, with a mean of 40.8 years. Sixty-four patients (41.8%) were found to have coexistent sinonasal morbidity preoperatively, the commonest being symptomatic deviated nasal septum (17.6%), chronic rhinosinusitis without polyps (11.1%) and chronic rhinosinusitis with polyps (3.3%). Rare instances of septal hemangioma (0.7%) and inverting papilloma (0.7%) were also seen. Postoperatively, there was cessation of cerebrospinal fluid rhinorrhea in 96.7% which rose to 100% after revision surgery in those with recurrence. Resolution of coexistent sinonasal pathology occurred in all patients with followup ranging from 10 to 192 months. New onset sinonasal morbidity which developed postoperatively included synechiae between middle turbinate and lateral nasal wall (5.9%) and sinonasal polyposis (1.3%). ConclusionPatients who undergo endoscopic cerebrospinal fluid leak repair may have coexistent sinonasal pathology which needs to be addressed prior to or along with repair of the dural defect. New onset sinonasal morbidity, which may arise in a few patients postoperatively, may require additional treatment. A protocol for the management of coexistent sinonasal conditions ensures a successful outcome.

Syrinx Secondary to Chiari-like Tonsillar Herniation in Spontaneous Intracranial Hypotension

Syrinx development in patients with spontaneous intracranial hypotension (SIH) has rarely been described. To better understand this entity, we compared the clinical and radiographic findings in a series of patients with SIH and acquired Chiari-like tonsillar herniation with and without syrinx formation. Six patients with syrinx in the setting of SIH and Chiari-like tonsillar herniation were retrospectively identified. The clinical and radiographic findings and outcomes were compared with those from a control group of patients with SIH and Chiari-like tonsillar herniation without syrinx. The patients with SIH and syrinx had had a higher opening pressure than had the control group (mean, 14.0 cm H2O vs. 7.4 cm H2O; P= 0.02) and a higher body mass index (mean, 33 kg/m2 vs. 26 kg/m2; P= 0.01). The patients with syrinx had had an average obex displacement of 3.7 ± 2.2 mm below the plane of the foramen magnum compared with a position of 1.9 ± 3.1 mm above the plane of the foramen magnum in the control group (P= 0.004). The mean tonsillar descent was 12.7 ± 4.7 mm below the foramen magnum in those with syrinx compared with 5.9 ± 2.5 in the control group (P= 0.009). The clinical symptoms had improved in 83.3% of the patients with syrinx and 75% of the control patients after spinal cerebrospinal fluid leak closure. Three patients (50%) also had radiographic syrinx reduction. Our results have shown that SIH can be an underrecognized cause of syrinx with key differences in body habitus and obex displacement compared with SIH without syrinx. In patients with tonsillar herniation into the foramen magnum associated with syrinx, the presence of SIH should be considered to avoid unnecessary foramen magnum decompression, even in those with a normal opening pressure.

Deossification of the Otic Bone in High Pressure CSF Otorhinorrhea: A New Radiological Finding.

To highlight a new radiological feature in a patient with labyrinthine malformation presenting with bilateral spontaneous high pressure cerebrospinal fluid (CSF) otorhinorrhea. Study design-retrospective case review. Setting-academic, tertiary cochlear implant center. A cochlear implantee with Incomplete Partition Defect (Type 1) presented with meningitis and CSF otorhinorrhea for which she initially underwent medical treatment. High resolution computed tomography (HRCT) of the temporal bone with CT cisternography was performed for identifying the site of the CSF leak. HRCT and CT cisternography revealed a defect in the region of the stapes foot plate and marked thinning/deossification of the cochlear promontory. These two findings were absent in the pre-implant imaging of the patient done 3years ago. Surgery by endaural approach was undertaken to close the site of CSF leak. Intraoperatively, marked thinning of the cochlear promontory was observed, corresponding to 'blue lining' of the labyrinth in otologic surgery. This intraoperative finding indicating high intralabyrinthine CSF pressure correlated well with the imaging findings. Primary surgical repair resulted in successful CSF leak closure followed by theco-peritoneal shunting to prevent recurrence of the leak. The patient is using her cochlear implant and doing well with auditory verbal therapy. She is asymptomatic till date. Thinning and deossification of the otic capsule on HRCT is an important indicator of high CSF pressure in patients with labyrinthine malformations. Our case study highlights the need for heightened radiological and clinical vigilance in this subgroup of patients to predict complications and ensure prompt intervention.

Chapter 12 - Role of the neurotologist in posterior fossa meningioma surgery

Posterior fossa meningiomas that impinge on structures of the temporal bone or clivus may be difficult to access for optimal resection that maximizes tumor control and minimizes short- and long-term morbidities. To address this challenge, the contemporary neurosurgery-neurotology team works collaboratively by managing patients jointly at every stage of care: preoperative evaluation, intraoperative intervention, and postoperative treatment. The neurotologist is important at all stages of posterior fossa meningioma surgery. First, detailed preoperative evaluation of auditory, facial, vestibular, and lower cranial nerve integrity enables assessment of new neurologic deficit risk, prognosis of functional recovery, and pros and cons of candidate surgical approaches. Second, intraoperative partitioning of surgical steps by provider and adopting an overlapping tumor resection philosophy creates an efficient and confident surgical team built on trust. Third, postoperative closure of cerebrospinal fluid leak and treatment of facial weakness, audiovestibular dysfunction, and voicing and swallowing impairments organized by the neurotologist reduces the impact of negative outcomes. The role of the neurotologist in posterior fossa meningioma surgery is to deliver nuanced evaluative metrics, facilitate shared decision making, perform precise bone and soft tissue microsurgery, and mitigate perioperative morbidities.

Faculty Attitudes Toward Rhinology Fellowship Training: A Survey of Rhinology Fellowship Programs.

The number of rhinology fellowship programs has grown rapidly over the past decade. To date, no standardization or accreditation process exists, raising the potential for disparate programs. The attitudes of faculty regarding training are important to elucidate the educational experience of rhinology fellowship. An anonymous, web-based survey of rhinology faculty assessed the subjective attitudes toward various domains of fellowship training including surgery, office-based procedures, research, and career development. A 5-point Likert-type scale assessing importance was used (1-not at all important, 5-extremely important). A total of 34 faculty (response rate 35.8%) completed the survey. The surgical procedures that received the highest mean importance scores were endoscopic surgery for advanced inflammatory disease (median = 5), cerebrospinal fluid leak closure (5), and extended endoscopic sinus surgery (5). The procedures with the lowest scores were nasal valve repair (2), inferior turbinate surgery (3), and open approaches to the sinuses (4). A wide range of responses was noted for the minimum target number of fellow cases for the surveyed procedures. Higher importance scores were noted for direct attending supervision (5) when compared to fellow autonomy (4, P < .001) or shadowing (3.5, P < .001) in the operating room. Higher scores were noted for career preparation in academic (4) versus private practice (3, P < .001) and providing opportunities for clinical (4) versus basic science research (2, P < .001). The majority of faculty felt that there were too many fellowship positions with respect to the market place for private practice (58.8%), academic jobs (85.3%), and overall societal need (61.8%). A range of faculty attitudes with respect to fellowship training was noted in this study. Continued assessment and refinement of the educational experience in rhinology fellowships is necessary.

Endoscopic Transmaxillary Transposition of Temporalis Flap for Recurrent Cerebrospinal Fluid Leak Closure.

Objective To describe the technique of endoscopic transmaxillary temporalis muscle flap transposition for the repair of a persistent postoperative sphenoidal cerebrospinal fluid leak. Design The repair of a recurrent cerebrospinal fluid leak for a patient who had undergone endoscopic transsphenoidal excision of an invasive silent corticotroph Hardy C and Knosp Grade IV pituitary adenoma was undertaken. The patient had completed postoperative radiotherapy for the residual tumor and presented with cerebrospinal fluid leak, 1 year later. The initial two attempts to repair the cerebrospinal fluid leak with free grafts failed. Therefore, an endoscopic transmaxillary transposition of the temporalis muscle flap was attempted to stop the cerebrospinal fluid leak. Results The endoscopic transmaxillary transposition of the vascularized temporalis muscle flap onto the cerebrospinal fluid leak repair site resulted in successful closure of the cerebrospinal fluid leak. Conclusion Endoscopic transmaxillary transposition of the temporalis flap resulted in closure of recurrent cerebrospinal fluid leak in a patient with recurrent pituitary adenoma, who had undergone previous surgery and radiotherapy. This technique has advantages over the endoscopic transpterygoid transposition of the same flap and could be used as a complementary technique in selected patients.

Preservation of Functioning Sinus in Frontal Sinus Posterior Table Fractures

Objective: Sinus preservation after posterior table frontal fractures (PTFF) may be preferable to obliteration/cranialization for minimizing risk of mucocele. This study assessed functional outcomes and complications after open reduction and internal fixation (ORIF) with sinus preservation for PTFF. Study Design: Consecutive case series. Patients and Methods: Patients with PTFF undergoing ORIF with sinus preservation from July 2012 to December 2013 were assessed. Fracture type/extent, presence/extent of dural injury, and cerebrospinal fluid (CSF) leak were recorded. Type of frontal sinusotomy, use of frontal stents, and lumbar drain were recorded. Outcomes evaluated were CSF leak closure, incidence of perioperative meningitis and frontal patency. Results: For two patients with intact dura and no CSF leak, displaced fragments were removed without dural repair. For one patient with CSF leak, a 1 cm dural defect was associated with comminuted PTFF; two-layered closure with underlay Duragen sheet and pericranial flap (PF) was performed. Lumbar drainage was not used. In two patients, Draf 2a frontal sinusotomy was performed with silastic stenting for 3 weeks. Frontal sinuses were aerated with widely patent frontal recess in all cases with no postoperative CSF leak, meningitis or cranial prolapse at mean 14.0 ± 5.0 months. Conclusion: Preservation of frontal sinus is an option for selected PTFF cases. Dural graft plus vascularized PF without a rigid layer may be used for frontal sinus CSF leak repair.

Endoscopic Transnasal Management of Cerebrospinal Fluid Rhinorrhea: Early Experience

Background: Cerebrospinal fluid (CSF) rhinorrhea results from abnormal communication between the subarachnoid space and the nasal cavities. During the last two decades the surgical management of anterior skull base fistulae has evolved from intracranial craniotomy to endoscopic transnasal repair with a high success rate and decreased morbidity. We recently changed our policy and repair CSF rhinorrhea through an endoscopic endonasal approach. The purpose of this work is to describe the technique used for watertight closure of CSF leak along the anterior skull base and to evaluate our early results. Methods: A prospective acquired database of all patients having undergone endonasal endoscopic repair of CSF leaks over a 20-month period at Military Hospital of Tunis starting in March, 2012 was reviewed. Results: A total of 20 patients underwent endoscopic repair of CSF fistula. The etiology was traumatic in 7 cases, spontaneous in 11, and iatrogenic in 2 associated with previous transsphenoidal pituitary surgery. A total of 19 patients had successful primary endoscopic repair of the CSF leak. One patient required a revision surgery due to early failure of the repair and the leak was plugged successfully on the second attempt. We experienced a single case of meningitis during the postoperative course. Conclusion: The overall success rate (100%) and low morbidity in this short series support endoscopic approach as standard of care for CSF leak closure.

Low-dose intrathecal fluorescein and etiology-based graft choice in endoscopic endonasal closure of CSF leaks

ObjectiveSkull base cerebrospinal fluid (CSF) leaks of various etiologies are increasingly repaired through the natural corridor using an endoscopic endonasal approach. Characteristics of the skull base defect significantly correlate with etiology, which should be ascertained to guide surgical management. The objectives of this study were to assess the long-term outcomes of patients that underwent endoscopic endonasal repair of CSF leak using low-dose intrathecal fluorescein (ITF) and an etiology-based algorithm for multi-layer graft closure. MethodsPatients were divided into 4 groups: A – congenital, B – post-traumatic, C – post-endonasal surgery, D – post-craniotomy. Low-dose ITF was utilized in all case series. Long-term clinical follow-up data, including perioperative complications associated with the use of intrathecal fluorescein and leak closure rates, were obtained retrospectively. Endoscopic visualization of fluorescein-stained CSF as well as the method of skull base closure and graft material is detailed. ResultsWe identified a total of 41 patients (N=24 in Group A, N=4 in Group B, N=12 in Group C and N=1 in Group D) that underwent 50 CSF leak repairs using the endoscopic endonasal approach with an average follow-up of 31.6 months. Nine patients (21.9%) had undergone a previous attempt at CSF leak repair. Lumbar drain was used intraoperatively in 26 patients (63.4%) and kept in place for an average duration of 3.25 days. ITF successfully identified the site of leak in 80.5% of cases regardless of etiology. Leaks were successfully closed in 92% of patients. One patient (2.4%) experienced transient leg weakness following lumbar drain placement. Another patient (2.4%) developed hydrocephalus requiring a ventriculoperitoneal shunt. ConclusionLow-dose ITF is a safe and useful adjunct to endoscopic endonasal repair of CSF leaks with minimal complications and successful localization of the leak in approximately 80%. An etiology-based approach to graft choice and duration of lumbar drain placement in CSF leak repair may optimize closure rates.

Training Cerebrospinal Fluid Leak Repair with Nasoseptal Flap on the Lamb's Head

Background: One of the major challenges of cranial base surgery is reconstruction of dural defects and cerebrospinal fluid leak closure. Various grafting methods have been used for smaller skull base defects with great success. The indications for endoscopic reconstruction have recently evolved to encompass much larger breeches in the skull base following tumor removal, thus emphasizing the need for vascularized tissue flaps for reconstruction. Methods: Some authors proposed a pedicled flap of the nasal septum mucoperiosteum and mucoperichondrium, which is very vascularized and has quite a large surface. It is also long enough to easily cover even larger defects of the skull base. The elevation of a nasoseptal flap is based on a particularly advanced surgical technique and thus requires proper training before being performed in a real patient. Results: Anatomical differences between human and lamb heads were observed and explained although they do not affect the procedure of the elevation of the nasoseptal flap. Conclusions: The lamb's head has been shown to be an ideal model for the adequate training of the surgical skills required for this demanding procedure.

Endoscopic Contralateral Superiorly Based Mucoperiosteal Nasal Septal Flap for Closure of Cerebrospinal Fluid Leak

Objective A novel local contralateral superiorly based mucoperiosteal nasal septal flap (CSBMNSF) for closure of a cerebrospinal fluid (CSF) leak from the middle anterior base of the skull is described. Materials and Methods A retrospective review of patients having endoscopic sinus surgery (ESS) with a CSF leak between 2000 and 2009 was performed. The surgical technique is described. Two vertical parallel incisions are performed anteriorly and posteriorly in the contralateral septal mucosa, joined inferiorly by a horizontal incision. Elevation of the flap is completed, leaving it pedicled superiorly. A window is created at the highest aspect of the nasal septum to allow transfer of the flap to the affected side. Results Four patients with a CSF leak post-ESS for excision of a congenital meningocele, tumor removal, and chronic sinusitis are described. All were treated successfully using a CSBMNSF. Conclusion A novel, easy-to-handle local flap for closure of defects in the anterior middle skull base is described. The use of this flap offers less morbidity and less bulkiness compared with other local or regional flaps.

A case of cerebrospinal fluid rhinorrhoea: a surgical challenge.

CEREBROSPINAL FLUID rhinorrhoea is defined as the leakage of CEREBROSPINAL FLUID through the nose due to communication between nasal cavity and Sub-arachnoid space. It occurs due to breach in 4 layers - mucosa of the nose and PNS, skull base, Duramater, Subarachnoid membrane. With the advent of nasal endoscope and advancement in technology, Endoscopic Endonasal closure of CEREBROSPINAL FLUID leak has reached tremendous heights due to exact localization and precise placement of graft. In this article, we are publishing a case report of Non-traumatic normal pressure CEREBROSPINAL FLUID leak of more than 1.5cm in size which was successfully closed Endoscopically by multilayered technique.

Novel Harvesting Technique of the Nasoseptal Flap in Large Sphenoidotomy Undergoing Revision With Transsphenoidal Approach

Blood supply to the nasoseptal flap (NSF) can be disrupted by large sphenoidotomies in an endonasal transsphenoidal approach (TSA). In such patients with recurrent sellar tumor, an NSF can be unavailable in the sellar reconstruction. Herein, we present a new harvesting method of the NSF in revision endonasal TSA, where injury to its vascular pedicle of the NSF by a large sphenoidotomy is highly suspected. Data for patients with large sphenoidotomy who underwent revision endonasal TSA and NSF at Chonnam National University Hwasun Hospital were collected consecutively from January 2010 to July 2011. A retrospective review of these cases was performed. Seven patients with a previous large sphenoidotomy requiring revision TSA underwent a new modification technique of the NSF. Pathologies included 6 pituitary adenomas and 1 craniopharyngioma. All patients had intraoperative cerebrospinal fluid (CSF) leak, necessitating multilayered sellar reconstruction, including NSF. No patients had flap necrosis, and closure of CSF leak was possible in 6 of 7 patients. Delayed CSF leak in a patient was due to the migration of the flap over the defect, and no septal complications such as septal perforation and saddle nose were noted. Our harvesting technique of the NSF in patients with recurrent sellar tumors is reliable for sellar reconstruction where the NSF may be unavailable because of previous large sphenoidotomy. This novel technique has an excellent success rate in flap viability and minimal additional endonasal morbidity.

Giant pseudomeningocele after spinal surgery: A case report

Very few reports have described giant pseudomeningoceles ≥ 8 cm in diameter. We report this case of the biggest giant pseudomeningocele at the unusual cervicothoracic level. A 59 year old man who underwent cervicothoracic laminectomy had a giant pseudomeningocele detected and the lesion gradually grew to about 15 cm in diameter by 2 years postoperatively. Cerebrospinal fluid leak closure was performed and the postoperative course was favorable. We present this case, review the literature and discuss the size and portion, mechanism of formation, symptoms and treatments of giant pseudomeningocele.