Repair Of Skull Base Defects Research Articles

Inaccurate Assessments of Anterior Cranial Base Malignancy following Nasoseptal Flap Reconstruction

Objective: The nasoseptal flap (NSF) provides vascularized tissue for repair of skull base defects of various etiologies. However, the NSF repair after skull base resection for anterior cranial base malignancies may demonstrate radiologic findings confusing for recurrent or residual disease on post-operative surveillance imaging. The objective of the current study was to review inaccurate assessments of suspected recurrent cranial base malignancy due to NSF reconstruction during post-operative radiologic evaluations.

Spontaneous Cerebrospinal fluid effusion of the temporal bone: Repair, audiological outcomes, and obesity

Spontaneous occurrence of otogenic cerebrospinal fluid (CSF) effusion is now far more prevalent than causes related to infections, prior surgeries, or trauma-trends that may be increasing because of higher rates of obesity and improved diagnostic awareness. In our patient cohort with spontaneous CSF effusion, we report its association with obesity and audiological findings before and after surgery. Retrospective study. In our 45 patients (46 ears) with CSF effusion (with or without lateral skull base meningoencephaloceles), we report clinical data, imaging studies, audiogram results, operative techniques, and recurrence rates. Causes included 33 spontaneous, 10 due to chronic otitis media, one iatrogenic, and one traumatic. Body mass index (BMI) averaged 35 overall (37 for spontaneous type and 32 for nonspontaneous type). Surgical repair of skull base defect was performed using three middle fossa approaches, 24 combined transmastoid/middle fossa, and 19 transmastoid alone. Overall recurrence of CSF leaks was 6.5%. Thirty patients had audiograms available. Sensorineural hearing loss occurred in 10% of patients. Air-bone gap improved by ≥ 15 dB in 20% of patients and worsened by ≥ 15 dB in 6.7% of patients. Patients with spontaneous CSF effusion had a BMI higher than in the nonspontaneous group, but the difference was not statistically significant. However, the dramatic trend toward spontaneous CSF effusion heightens the need for clinician's acumen for diagnosis, particularly in overweight/obese patients. Our audiological outcomes confirm the efficacy of surgical approaches in correcting conductive hearing loss and preserving bone conduction, although hearing loss is a risk during surgical repair. 4. Laryngoscope, 124:1204-1208, 2014.

Porcine small intestine submucosal graft for endoscopic skull base reconstruction

Skull base defects and encephaloceles of the sinus and nasal cavities are routinely repaired endoscopically using a variety of materials including bone, cartilage, fascia, acellular dermal allografts, and xenografts, with high success rates. However, there is a paucity of data regarding the use of porcine small intestine submucosal (SIS) grafts for endoscopic dural repair. The purpose of the current study was to review outcomes using SIS grafts in the endoscopic reconstruction of skull base defects. Review of prospectively collected data regarding skull base defect repair using SIS was performed. Demographics, location, and size of skull base defect, method of repair, successful closure, and complications were recorded. Over 4.5 years, 155 patients (mean age 49 years) underwent 170 primary skull base repairs using porcine SIS. Etiologies included tumor (76), spontaneous (51), trauma (37), and congenital (5). The majority of repairs were in combination with a nasoseptal flap (n = 113). Average defect size (length vs width) was 13 × 10.5 mm. Success rate on first attempt was 94.7% (161/170), and all defects were effectively sealed on subsequent endoscopic revision. The average follow-up was 77 weeks. Major postoperative complications, including recurrent cerebrospinal fluid (CSF) leak (9), meningitis (1), periorbital cellulitis (1), and invasive fungal sinusitis (1), occurred in 6.4% of individuals with no long-term sequelae. Use of porcine SIS dural graft was associated with excellent outcomes in this study and evidence presented here supports its routine use in the endoscopic closure of skull base defects.

Endoscopic reconstruction of skull base defects using a nasal septal flap in paediatric patients

EnAbstract Introduction The repair of skull base defects after skull base surgeries is a major problem. Postoperative cerebrospinal fluid leak in reconstruction of the anterior skull base defect using a nasal septal flap was minimal when compared with other techniques. The nasal septal flap should be considered as the first line of treatment after transnasal endoscopic skull base surgery. Objectives Evaluation of the usefulness and reliability of endoscopic endonasal skull base reconstruction using a nasal septal flap. Patients and methods This study was carried out on 10 paediatric patients with skull base defects because of different pathologies. These patients were admitted in El-Kasr El-Ainy Hospital, Otorhinolaryngology Department. These patients included one patient with a germ cell tumour, five patients with a congenital encephalocele and four patients with skull base defects because of trauma to the skull base. Results and conclusion Various endoscopic techniques have been described to separate the cranial cavity from the sinonasal cavity to prevent infection, pneumocephalus and cerebrospinal fluid leak. Different techniques were used to close the anterior skull base defects such as multilayer free graft, suturing the dural defect combined with free graft and reconstruction based on a vascularized graft. The nasal septal flap should be considered as the first line of treatment after transnasal endoscopic skull base resections.

Design of an Endonasal Graft Placement Tool for Repair of Skull Base Defects

Poor tools lead to dropped gra7s, decreased surgeon confidence, increased opera<ng <me Forceps: • cannot reliably open and close in 6ght spaces • good grip • poor force applica6on Blunt Tools: • good force applica6on • poor grip • difficulty handling varying gra: size, shape, rigidity Endonasal Approach • Minimally invasive • Limited tool manipulability • Gra: placement can add up to 30 minutes Inadequate Gra7 Placement Complica<ons • CSF leaks that lead to meningi6s, brain hemorrhage, neurological deficits, or death1

Delayed Cavernous Carotid Artery Pseudoaneurysm Caused by Absorbable Plate Following Transsphenoidal Surgery: Case Report and Review of the Literature

Background Bioabsorbable plates are frequently utilized in the repair of skull base defects following transsphenoidal operations. Traumatic intracranial pseudoaneurysms are a rare complication of transsphenoidal surgery. To date, iatrogenic carotid pseudoaneurysm associated with the use of an absorbable plate has been reported once.Results A 57-year-old man with a large nonfunctional pituitary macroadenoma underwent an endoscopic transsphenoidal operation with gross total resection. An absorbable plate was placed extradurally to reconstruct the sellar floor. He experienced delayed repeated epistaxis, followed by a right middle cerebral artery distribution embolic stroke. Computed tomorgraphy (CT) angiogram 6 weeks postoperatively revealed a 6 × 4 mm pseudoaneurysm located on the medial wall of the right cavernous internal carotid artery. Stent coiling was used to successfully obliterate the pseudoaneurysm, and the patient fully recovered.Conclusion Delayed erosion of the carotid artery wall caused by a plate used to reconstruct the sellar floor may manifest with epistaxis or embolic stroke. The authors' preference is to avoid insertion of a rigid plate for sellar floor reconstruction in the absence of intraoperative cerebrospinal fluid (CSF) leaks, unless it is required to buttress a large skull base defect. Short-segment embolization with stent coiling is the preferred treatment option for carotid pseudoaneurysms following transsphenoidal operations.

Endoscopic and Open Resection of Sphenoid Sinus Meningoencephaloceles with Repair of Skull Base Defects

Objective: To describe the diagnosis, resection, and repair of 11 sphenoid meningoencephaloceles through combined endoscopic and open techniques.

Cranial Base Repair with Combined Vascularized Nasal Septal Flap and Autologous Tissue Graft Following Expanded Endonasal Endoscopic Neurosurgery

The expanded endonasal endoscopic approach provides excellent visualization and access to midline skull base lesions, albeit with a relatively high risk of postoperative cerebrospinal fluid (CSF) leakage. We present our experience with the expanded endonasal endoscopic approach to the skull base in an institution where, previously, a traditional transsphenoidal approach with a surgical microscope had been used. We performed a retrospective review to identify patients who underwent expanded endonasal endoscopic surgery and analyzed demographic, pathological, and operative data with particular attention to repair of the skull base defects in 55 procedures performed on 49 patients. We compared the outcomes of 10 primary operations in which we repaired skull base defects using only autologous or allogeneic tissue grafts and 39 primary operations in which we used a vascularized mucoperichondrial nasal septal flap with or without a layered autologous tissue graft. Primary expanded endonasal endoscopic procedures were performed in 49 patients with sellar pathology (33 pituitary adenomas, 4 Rathke's cleft cysts, 1 pituicytoma, 1 pituitary metastasis) and non-sellar pathology (3 meningiomas, 3 clival chordomas, 1 clival mucocele, 1 craniopharyngioma, and 2 esthesioneuroblastomas). Postoperative CSF leakage occurred following 5 of the 49 primary operations (10.2%). This occurred in 2 of 10 primary operations (20.0%) in which the skull base defect was repaired using only autologous and/or allogeneic tissue grafts, necessitating a total of 3 operative CSF leak repairs in those 2 patients. The remaining 3 postoperative CSF leaks occurred in the 39 primary operations (7.7%) in which skull base repair was performed using a mucoperichondrial nasal septal flap, necessitating operative repair in 2 of those patients. The repair of skull base defects created during expanded endonasal endoscopic surgery is improved by use of a mucoperichondrial nasal septal flap combined with a layered autologous tissue graft. When CSF leakage occurs despite nasal septal flap closure, the site of the leakage may be easier to localize and repair.

Assessment of Mucocele Formation after Endoscopic Nasoseptal Flap Reconstruction of Skull Base Defects

Advances in endoscopic skull base (SB) surgery have led to the resection of increasingly larger cranial base lesions, resulting in large SB defects. These defects have initially led to increased postoperative cerebrospinal fluid (CSF) leaks. The development of the vascularized pedicled nasoseptal flap (PNSF) has successfully reduced postoperative CSF leaks. Mucocele formation, however, has been reported as a complication of this technique. In this study, we analyze the incidence of mucocele formation after repair of SB defects using a PNSF. A retrospective review was performed from December 2008 to December 2011 to identify patients who underwent PNSF reconstruction for large ventral SB defects. Demographic data, defect site, incidence of postoperative CSF leaks, and rate of mucocele formation were collected. Seventy patients undergoing PNSF repair of SB defects were identified. No postoperative mucocele formation was noted at an average radiological follow-up of 11.7 months (range, 3–36.9 months) and clinical follow-up of 13.8 months (range, 3–38.9 months), making the overall mucocele rate 0%. The postoperative CSF leak rate was 2.9%. Proper closure of SB defects is crucial to prevent CSF leaks. The PNSF is an efficient technique for these repairs. Although this flap may carry an inherent risk of mucocele formation when placed over mucosalized bone during repair, we found that meticulous and strategic removal of mucosa from the site of flap placement resulted in a 0% incidence of postoperative mucocele formation in our cohort.

Use of Endoscopic Vascularized Nasoseptal Flap in Children

Objective: 1) Determine ability to achieve 100% coverage of sellar skull base defects with the vascularized nasal septal flap in pediatric patients. 2) Identify the rate of residual CSF leaks following this repair technique in these pediatric patients. 3) Review the demographics and perioperative course in these children. Method: Study design: Retrospective case series. Study conducted: January 1, 2006, to January 1, 2012. Condition studied: Repair of skull base defects after resection of sellar lesions. Subjects: Children. Setting: Children’s hospital. Intervention: Endonasal repair of skull base defects with a vascularized nasoseptal flap. Outcome measurement(s): 1) Complete coverage of defect. 2) Postoperative CSF leak. Results: Demographics: Ten children were identified, and 11 flaps were performed. The average patient age was 12.6 years old (range of 5.1-17.4 years). Total coverage was achieved in all cases. The technique was particularly challenging in the younger patients. A brisk CSF leak was observed during closure in 3 cases, but no CSF leaks were observed after balloon packing removal (day 5). No lumbar drains were used. Only minor complications were observed. A second look with debridement of packing material due to poor cooperation with office endoscopy was done in 7 children (70%). Conclusion: The endonasal vascularized nasal septal flap is a feasible and reliable method of repair of dural defects after resection of sellar lesions in children. Despite active CSF leak in 3 children, there were no residual CSF leaks. Unlike adult patients, children may require operative nasal debridement after repair has healed.

Endoscopic Skull Base Reconstruction: Lesson from 420 Cases

Objective: The ability to repair skull base defects resulting from the treatment of different skull base diseases has been a major challenge over the past decade. Aims of the study are to define different endoscopic techniques of reconstruction, focusing on their evolution, and evaluate their efficacy and indications, analyzing their failures. Method: All cases submitted to endoscopic skull base reconstruction from 1995 to 2011 were divided into group A: patients treated for traumatic or non-traumatic CSF-leaks and group B: patients treated for skull base tumors. Patients were fully investigated prior to surgery with endoscopic evaluations and neuroimaging, eventually associated to other in-depth examinations. Results: 420 patients underwent endoscopic skull base reconstruction: 263 in group A and 157 in group B. Primary closure was achieved in 251/263 cases of group A (95.4%) and in 143/157 cases of group B (91.1%). In 26/420 failures (6.2%) revision surgery reached an effective secondary closure of the defect in 100% of cases. Autologous materials were preferred for grafting in both groups, with prevalence for intranasal epithelial and connective tissues (mucoperiostium, bone, cartilage) in group A and for extranasal connective tissue (fascia lata) in group B. Vascularized flaps were employed in selected cases. Indications and details of each technique are provided. Conclusion: The endoscopic technique should be considered a favorable, safe, and minimally invasive procedure for skull base reconstruction with effectiveness rates comparable to external approaches. Failures were related to mistakes in the choice of materials and reconstructive technique, based on the site of the defect and the biology of treated lesions.

Surgical Repair of Skull Base Defect Following Standard or Extended Endoscopic Transsphenoidal Surgery for Pituitary Tumors

Surgical Repair of Skull Base Defect Following Standard or Extended Endoscopic Transsphenoidal Surgery for Pituitary Tumors

Treatment Strategies for Lateral Sphenoid Sinus Recess Cerebrospinal Fluid Leaks

To highlight concepts critical to achieving successful repair and avoiding intracranial complications in the treatment of cerebrospinal fluid (CSF) leaks from the lateral recess of the sphenoid sinus (LRS). Outcomes study. Tertiary referral university hospital. Eleven patients with LRS CSF leaks from June 2008 to June 2010. Endoscopic transpterygoid approach and multilayer repair of skull base defect in the LRS. Recurrence, graft techniques, postoperative intracranial pressure (ICP), and use of ventriculoperitoneal (VP) shunt. Thirteen CSF leaks originating in the LRS were surgically repaired in 11 patients; 2 patients required bilateral leak repair. The endoscopic transpterygoid approach was used in 12 of 13 repairs. Eight patients had failed attempts at repair prior to presentation (4 endoscopic sphenoidotomies and 4 middle cranial fossa [MCF] approaches). One patient presented with a temporal lobe abscess following hydroxyapatite "obliteration" to seal off the LRS. This required a combined MCF/transpterygoid approach to drain the abscess, remove the encephalocele and hydroxyapatite, and seal the skull base defect. In 2 cases, the LRS was left patent owing to concerns of inadequate mucosal extirpation. The median duration of follow-up was 10.8 months (range, 2-29 months). One patient experienced a failure (2 months after repair), which was successfully sealed on the second attempt. Postoperatively, 5 patients required VP shunts, and 5 were maintained on acetazolamide for elevated ICP (average, 26.7 cm H₂O in 8 patients; presumed elevated in 2 patients). The current study demonstrated a 92% success rate using the endoscopic transpterygoid approach for LRS skull base defects providing support for routine use in the treatment algorithm. Poor outcomes were observed with previous surgical attempts to obstruct the LRS without repairing the skull base defect.

Efficacy of the pedicled nasoseptal flap without cerebrospinal fluid (CSF) diversion for repair of skull base defects: incidence of postoperative CSF leaks

The advances in endoscopic skull base surgery have led to the resection of increasingly larger cranial base lesions and the creation of larger skull base defects with the potential for increased postoperative high-flow cerebrospinal fluid (CSF) leaks. These concerns led to the development of the vascularized pedicled nasoseptal flap (PNSF), which is now used as the mainstay for repair of large skull base defects in many academic centers. In this report, we review the incidence of postoperative CSF leaks in our institution in patients undergoing endoscopic skull base repair of high-flow CSF leaks with a vascularized PNSF without concurrent CSF diversion. We performed a retrospective analysis at our tertiary care medical center on patients who underwent endoscopic repair of high-flow CSF leaks using a PNSF without CSF diversion between July 2008 and August 2011. Repair materials, incidence of postoperative CSF leaks, and demographic data were collected. Fifty-nine high-flow CSF leaks were repaired with a PNSF and other repair materials, without the use of lumbar catheter drainage. No postoperative CSF leak occurred in this cohort of patients. The overall postoperative CSF leak rate was 0%. Meticulous multilayer-closure of skull base defects is critical to prevent postoperative CSF leaks. Although lumbar drainage may be useful in select scenarios, it carries inherent risks of intracranial hypotension and pneumocephalus, and may not be necessary for routine management of high-flow CSF leaks in conjunction with a robust PNSF. Further prospective randomized controlled studies may be warranted to evaluate the efficacy of postoperative lumbar drainage.

Risk Factors Associated With Repair of Orbital and Lateral Skull Defects

To explore the complications and associated risks factors after orbital exenteration and lateral skull base defect repair. Patients who had undergone a reconstruction of their orbital cavity and lateral skull base defects were selected from our departmental database. The outcome of interest was postoperative complications. The risks factors were defined as age, sex, history of radiation therapy, and intracranial involvement (with and without dural involvement). Information was collected on the type of reconstruction used after the orbital cavity repair. The χ2 test and logistic regression were used to analyze associations between postoperative complications and the various risks factors. Of the 32 identified patients, 19 had intracranial involvement (9 with dural involvement). Twenty-four patients underwent reconstruction with free tissue transfer in the same setting. Reconstruction with free tissue transfer was significantly associated with fewer major postoperative complications (P < .053). There was a trend toward more complications with a history of radiation therapy or intracranial involvement. Reconstruction of the orbital cavity and lateral skull base can be challenging, especially if there is a history of radiation therapy and intracranial involvement. Free tissue transfer is a safe and effective method for reconstruction of such defects.

Endoscopic Nasoseptal Flap Repair of Skull Base Defects: Is Addition of a Dural Sealant Necessary?

Background: We compared the incidence of postoperative cerebrospinal fluid (CSF) leaks in patients undergoing endoscopic skull base repair with a pedicled nasoseptal flap (PNSF), with or without the addition of a dural sealant. Methods: A retrospective analysis of a prospective database was performed on patients who underwent endoscopic repair of high-flow CSF leaks using a PNSF between December 2008 and August 2011. Repair materials, incidence of postoperative CSF leaks, and demographic data were collected. Results: Thirty-two high-flow CSF leaks were repaired with a PNSF alone without dural sealant (Group I), and 42 were repaired with a PNSF with the addition of a dural sealant (Group II). In Group I, there were no postoperative CSF leaks (0%), whereas in Group II, there was one delayed postoperative CSF leak, resulting in a 2.4% leak rate. The incidence of postoperative CSF leakage was not significantly different between the two groups (P > 0.05). The overall postoperative CSF leak rate was 1.4% in this cohort. Conclusions: The use of dural sealants when performing endoscopic PNSF repair of high-flow CSF leaks is not supported by our data. In addition, this practice may significantly increase surgical cost. We encountered no postoperative CSF leaks in patients with high-flow CSF leaks treated with PNSF alone without dural sealants. Meticulous surgical technique and proper positioning of the PNSF seem to obviate the need for dural sealants during endoscopic skull base reconstruction of high-flow CSF leaks.

An endoscopic approach to reconstruction of skull base defects using a vascular pedicled nasoseptal mucoperiosteal flap

To introduce a method and the clinical effects of repairing skull base defects and dural defects using vascular pedicled nasoseptal mucoperiosteal flaps through an endoscopic endonasal approach. The clinical and follow-up data for 8 patients who underwent endoscopic endonasal reconstruction of skull base defects and cerebrospinal fluid rhinorrhea with a vascular pedicled nasoseptal mucoperiosteal flap between July 2008 and March 2010 were retrospectively reviewed. All patients were male. The age of these patients ranged from 28 to 60 years (average 41 years). The diagnosis for these patients included one hemangiopericytoma of the anterior skull base one olfactory neuroblastoma (type of Kadish C), one ethmoid sinus cancer, three local recurrent cancers of the nasopharynx after radiotherapy, one carcinoid of skull base and one traumatic cerebrospinal fluid rhinorrhea with recurrent intracranial infection. There were six anterior skull base defects and two middle cranial fossa defects. An endoscopic endonasal surgical approach was used for the repair. A pedicled flap using the nasal septal mucoperiosteum based on the posterior nasal artery was harvested from the ipsilateral side. The tissue flap was used to cover the dural defects. The margin was covered with gelatin sponge and fixed with fibrin glue. The nasal cavity was packed with iodoform gauze, a Foley catheter balloon and Merocel in this sequence to secure the flap in place. Nasal packing was removed 5 to 7 days postoperatively. Partial septal flap necrosis was found in one case, but the flaps in the other 7 cases survived. A postoperative cerebrospinal fluid leak occurred in one case 7 days after surgery. This was re-explored and successfully repaired with abdominal fat. All cases healed well, with no delayed cerebrospinal fluid leaks or intracranial infections during the 6 to 24 months follow-up period. The vascular pedicled nasoseptal mucoperiosteal flap is a reliable choice for endoscopic endonasal skull base reconstruction.

Clinical Efficacy of Radiation-Sterilized Allografts for Sellar Reconstruction after Transsphenoidal Surgery

The aim of this study was to assess the safety and efficacy of radiation-sterilized allografts of iliac bone and fascia lata from cadaver specimens to repair skull base defects after transsphenoidal surgery. Between May 2009 and January 2010, 31 consecutive patients underwent endonasal transsphenoidal surgery and all patients received sellar reconstruction using allografts following tumor removal. The allografts were obtained from the local tissue bank and harvested from cadaver donors. The specimens used in our approach were tensor fascia lata and the flat area of iliac bone. For preparation, allografts were treated with gamma irradiation after routine screening by culture, and then stored at -70℃. The mean follow-up period after surgery was 12.6 months (range, 7.4-16 months). Overall, postoperative cerebrospinal fluid (CSF) leaks occurred in three patients (9.7%) and postoperative meningitis in one patient (3.2%). There was no definitive evidence of wound infection at the routine postoperative follow-up examination or during re-do surgery in three patients. Postoperative meningitis in one patient was improved with the use of antibiotics and prolonged CSF diversion. We suggest that allograft materials can be a feasible alternative to autologous tissue grafts for sellar reconstruction following transsphenoidal surgery under selected circumstances such as no or little intraoperative CSF leaks.

Endoscopic Nasoseptal Flap Repair for Persistent CSF Leak after Open Skull Base Surgery

Background: Persistent cerebrospinal fluid (CSF) rhinorrhea after external skull base (SB) surgery is challenging to manage clinically owing to the high risk of meningitis, brain abscess, surgical morbidity associated with revision craniotomy, and the lack of available healthy autologous tissue after failure of a pericranial flap. Given the recent success of the nasoseptal flap (NSF) for endoscopic repair of large SB defects, we have adopted this technique as a salvage method for persistent CSF rhinorrhea after failure of external SB defect repair.

Cabergoline-Induced Cerebral Spinal Fluid Leak in a Patient With a Large Prolactinoma and MEN1

Abstract: Cerebral spinal fluid (CSF) rhinorrhea immediately after the initiation of cabergoline in prolactinoma patients is an uncommon complication that could lead to serious comorbidities and management difficulties. We present a case of a woman with multiple endocrine neoplasia type 1 syndrome and a recurrent macroprolactinoma, who developed CSF rhinorrhea and pneumocephalus after 3 doses of 0.5 mg cabergoline. The patient was treated for sinusitis after complaining of increasing headache. Imaging revealed a large pituitary tumor, skull base erosion, and pneumocephalus. Skull-base defect repair and subsequent transsphenoidal tumor debulking was performed. Prolactin continued to increase postoperatively, and the dopamine agonist (DA) was changed to bromocriptine, with no further CSF leak during 18 months of follow-up. We recommend urgent surgical repair as the treatment of choice for CSF leak following DA treatment. Concurrent surgical tumor debulking should be preformed if possible. Retreatment with DA is a safe option in most cases. To our knowledge, CSF rhinorrhea following cabergoline therapy has not been described in the multiple endocrine neoplasia type 1 syndrome.