The posterior pedicle inferior turbinate flap: a new vascularized flap for skull base reconstruction

Endoscopic Reconstruction of the Sellar Floor by Extended Inferior Turbinate Flap in Recurrent Pituitary Tumors

Objective  This aim of this study was to address the outcome of endoscopic reconstruction of the sellar floor by extended inferior turbinate flap. Patients and Methods  This is a retrospective study of 34 patients with a recurrent pituitary tumor. They were treated between March 2018 and December 2021 by endoscopic extended endonasal approach with the reconstruction of the sellar floor by an extended posterior pedicle inferior turbinate flap. The clinical and radiological follow-up was performed immediately postoperation and regularly every 3 months up to 1 year, and the available data from the last follow-up visit were included in the analysis. Results  The patients' age ranged between 40 and 65 years, with a slight female predominance (55.9%). Headache was the main presentation (47.1%), and functional tumors were found in 50.0% patients. Visual disturbances were field defects among 61.8% and papilledema among 52.9% patients. Preoperative endoscopy revealed postseptectomy as the significant finding (73.5%), followed by postseptectomy and adhesion (14.7%) and finally postseptectomy and hypertrophied inferior turbinate (11.8%). Total tumor resection was achieved in 76.5%, visual improvement was recorded in 52.9%, and no complications were reported in 82.4% patients. Cerebrospinal fluid (CSF) leak was not reported in any of the studied patients. Finally, total resection was significantly associated with younger age, non-functioning tumor and improvement of headache. Conclusion  The extended inferior turbinate flap is an effective and safe approach for sellar floor reconstruction in endoscopic endonasal surgery for recurrent pituitary tumors. The extension overcomes the relatively small inferior flap and its limited arc of rotation.

Superiorly Based Middle Turbinate Flap for Repair of Cerebrospinal Fluid Rhinorrhea: A Cadaveric Feasibility Study and Case Series

Objectives  Cerebrospinal fluid (CSF) leaks of the anterior cranial base are frequently repaired with endonasal, multilayered reconstructions. Vascularized tissue flaps are superior to free mucosal grafts and biomaterials in many cases. Limitations of previously described flaps include reach, rotation, pedicle availability, and postoperative sinonasal morbidity. The objective of this study is to describe the superiorly based middle turbinate flap, a novel vascularized mucosal reconstruction option, and to present a case series demonstrating flap utility. Design  Cadaveric feasibility study with technical description and illustrative case series. Setting  Tertiary medical center. Participants  Three silicone-injected cadaveric specimens (6 sides); 7 patients with CSF rhinorrhea from bony dehiscence of the anterior cranial fossa repaired with a superiorly based middle turbinate flap. Outcome Measures  Cadaveric feasibility, in vivo repair outcomes, sinonasal symptoms, and postoperative healing. Results  Cadaveric dissection demonstrated a consistent vascular plexus arising from the anterior and posterior ethmoid arteries, originating at the superior attachment of the middle turbinate and traveling inferiorly to supply the mucosa of the middle turbinate. Mean surface area of the flap was 776.67 ± 114.60 mm 2 . The clinical series of 7 patients involved leaks around the cribriform plate and fovea ethmoidalis. There were no instances of repair failure. All cases showed rapid and complete remucosalization without significant sinonasal morbidity. Conclusion  The superiorly based middle turbinate flap is a reliable, versatile, and effective option for a vascularized mucosal flap onlay that can be used in anterior skull base reconstruction. This flap is particularly useful in the repair of defects involving the cribriform plate and fovea ethmoidalis.

Pedicled nasal flaps in transnasal endoscopic surgery: review of indications and surgical techniques

At present an exclusive endoscopic endonasal approach is sufficient in the majority of cases to treat pathologies involving the sinonasal compartment and the surrounding anatomical subsites (e.g. orbit, ventral skull base, upper parapharyngeal space, etc.) with the advantage of minimising surgical invasiveness. In this context, nasal vascularised local flaps are widely employed because they represent a more effective option for reconstruction or preservation of noble/vital structures compared to grafts. On the other hand, the surgical extension and morbidity are minimised compared to regional or free flaps. Several nasal local flaps have been described in the literature: the aim of this review is to examine their applications, characteristics, indications, success rates and morbidities. Different nasal flaps based on single or multiple pedicles have been described; the choice between them is based on different factors such as the flap’s shape and dimension, localisation of the pedicle’s origin, width of rotation angle, previous surgeries which could compromise vascularisation, and surgical experience, in addition to the position and dimension of the area which must be resurfaced.

Posterior pedicle inferior turbinate flap for recurrent cerebrospinal fluid leak following endoscopic transsphenoidal surgery

BACKGROUND

Adequate reconstruction of skull base following endoscopic transsphenoidal surgery is the most crucial step in reducing postoperative morbidity and mortality. Although, the success rate of traditional nasoseptal flap is very high, specific surgical scenarios preclude its use. A variety of vascularised endonasal and tunnelled scalp flaps have been described in the literature to address such situations. Posterior pedicle inferior turbinate flap (PPITF) is one such locally available vascularised flap.

METHODS

Two patients with recurrent CSF leak following endoscopic transsphenoidal resection of pituitary adenoma were included. The nasoseptal flap was not available in both patients due to previous surgery. Hence, a PPITF based on the posterolateral nasal artery, a branch of sphenopalatine artery, was harvested and used for skull base reconstruction.

RESULTS

In both patients, CSF leak subsided in the immediate postoperative period. In one patient, sensorium improved and was subsequently discharged in stable condition. Other patient succumbed to meningitis in the postoperative period.

CONCLUSIONS

The PPITF is a valuable alternative to the conventional nasoseptal flap when the latter is not available and it is very important for an endoscopic skull base surgeon to be familiar with the technique of harvesting and using the PPITF.

Reducing CSF complications by a recycled Hadad's flap combined with autologous mucosa in secondary endoscope transsphenoidal surgery

Background

Transsphenoidal secondary operations are a minority but not a rare occurrence. How to viably prevent cerebral fluid (CSF)-related complications and confine surgery-caused injury in secondary surgery as minimally as possible is a huge challenge. This article shares our solution of recycling a prior Hadad-Bassagasteguy flap (HBF) along with a using small piece of free autologous mucosa to reconstruct the skull base.

Methods

Of 69 patients, fitted criteria were assigned into 2 different groups: a recycled HBF incorporated with an autologous free mucosa and a recycled HBF incorporated with an artificial dura to rebuild the skull base in secondary transsphenoidal surgery. The postoperative morbidities of pseudomeningocele, CSF leakage and meningitis were recorded and analyzed.

Results

A recycled HBF incorporated with an autologous mucosa is capable of reducing CSF complications compared to that of the matched group, particularly decreasing the morbidity of meningitis in secondary transsphenoidal surgery. Diabetes mellitus, craniopharyngioma, chordoma and the utilization of artificial dura were independent risk factors for CSF complications in secondary transsphenoidal surgery through univariate and multivariate logistic regression. In addition, diabetes mellitus and artificial dura are more likely to induce CSF leakage and meningitis. Patients suffering from craniopharyngioma are more susceptible to meningitis. Chordoma indiscriminately increased the risk of each CSF complication.

Conclusion

A recycled HBF incorporated with an autologous mucosa is reliable for reconstructing the skull base in secondary transsphenoidal surgery, especially for patients simultaneously suffering from diabetes mellitus and central skull base tumors.

Bilateral Inferior Turbinate Flaps for Salvage Reconstruction after Proton Beam Radiotherapy for Clival Chordoma

Clival chordoma is a rare, aggressive, notochord-derived tumor primarily managed with surgery via an endoscopic endonasal approach (EEA) and adjuvant proton beam radiotherapy. Reconstruction is commonly performed with a nasoseptal flap (NSF) at the time of initial surgery. While failures of the NSF are rare, they can occur following the initial surgery or in the setting of osteoradionecrosis. Salvage repair typically requires transfer of alternative vascularized tissues outside of the previously radiated field including regional scalp flaps such as pericranial or temporoparietal fascial flaps, or free vascularized tissue transfer. Here we describe the case of a 29-year-old woman with a history of clival chordoma with widespread skull base osteomyelitis secondary to NSF necrosis after proton beam radiotherapy. We describe successful skull base reconstruction with intranasal bilateral inferior turbinate flaps based on the sphenopalatine artery with lateral nasal wall extension, despite prior proton beam therapy and a failed prior vascularized intranasal reconstruction.

Anterior Skull Base Reconstruction

Anterior skull base reconstruction requires careful preoperative planning to use the most effective technique for the expected defect. Adherence to the principles of skull base reconstruction is imperative to minimize complications and improve patient outcomes.

Triple Layer Oronasal Fistula Repair Using Local Endonasal Flaps: Case Series of Three Patients

Oronasal fistula (ONF) is a common complication encountered after palatoplasty. Repair is indicated when symptoms impact speech and swallowing. In spite of the variety of surgical approaches described to repair these defects, recurrence rates remain high. Traditionally, successful closure is said to be achieved in using a double-layered approach due to the three-dimensional aspect of the defect. The extent of the fistula into the nasal cavity has incited an increased curiosity in using local endonasal flaps. In recent years, endonasal reconstructive procedures have seen increased interest and application, from cranial base defect repairs to orbital reconstruction and beyond. The nasoseptal (NSF) and inferior turbinate flaps (ITF) possess a robust arterial supply and an exceptional reach with excellent results demonstrated in large defect repair. However, the use of these flaps in ONF repair is scarcely discussed in the literature, and their effectiveness is relatively undetermined. In this manuscript, we present a series of three patients who underwent a triple layer ONF closure, with the oral portion incorporating a turn-in mucosal flap plus a local palate rotation flap or greater palatine artery pedicled-rotation flap, and a NSF or an ITF for the nasal portion of the defect.

Predictive model for preoperative risk calculation of cerebrospinal fluid leak after resection of midline craniofacial mass lesions

Background

Complex anterior skull base defects produced by resection of mass lesions vary in size and configuration and may be extensive. We analyzed the largest single-center series of midline craniofacial lesions extending intra- and extracranially. The study aims at the development of a predictive model for preoperative measurement of the risk of the postoperative cerebrospinal fluid (CSF) leak based on patients' characteristics and surgical plans.

Methods

166 male and 149 female patients with mean age 40,5 years (1 year and - 81 years) operated for benign and tumor-like midline craniofacial mass lesions were retrospectively analyzed using logistic regression method (Ridge regression algorithm was selected). The overall CSF leak rate was 9.6%. The ROSE algorithm and 'glmnet' software suite in R were used to overcome the cohort's disbalance and avoid overtraining the model.

Results

The most influential modifiable negative predictor of the postoperative CSF leak was the use of extracranial and combined approaches. Use of transbasal approaches, gross total resection, utilization of one or two vascularized flaps for skull base reconstruction were the foremost modifiable predictors of a good outcome. Criterium of elevated risk was established at 50% with a specificity of the model as high as 0.83.

Conclusions

The performed study has allowed for identifying the most significant predictors of postoperative CSF leak and developing an effective formula to estimate the risk of this complication using data known for each patient. We believe that the suggested web-based online calculator can be helpful for decision making support in off-pattern clinical situations.

Surgical Approaches to the Third Ventricle: An Update

The third ventricle is located in the deepest part of the brain and is delimited by both telencephalic and diencephalic structures. Its location makes every surgical procedure inside or around it quite challenging, due to the distance from the surface to the fragility of the neurovascular structures that is necessary to dissect before entering its cavity and to the narrow surgical corridors through which it is necessary to work. Its geometric localization inside the cranial cavity and the anatomical relationship with the interhemispheric fissure offers nevertheless to the surgeon an impressive variety of surgical approaches, which allow to reach every millimeter of the third ventricle lumen. Mastering properly all these approaches requires an impressive anatomical knowledge, the best available technology, and most refined technical skills, making the surgery of the third ventricle a point of excellence in the evolution of each neurosurgeon. The development of neuronavigation and neuroendoscopy has been a revolution in neurosurgery in the last 20 years and offered special advantages for the surgery of the third ventricle. In fact, the narrow corridors of approach make the precision of the neuronavigation and the enlightenment and magnification of the neuroendoscopy especially useful to reach the third ventricle cavity and working inside or around it. This chapter reviews the history of the surgery of the third ventricle and offers an update of the variety of surgical corridors identified and of the technology now available to properly work through them and inside the third ventricle cavity.

Endonasal skull base repair with a vascularised pedicled temporo-parietal myo-fascial flap

Objective

Expanded endonasal approaches (EEAs) to the skull base have increased the scope and extent of pathologies that can be treated endoscopically. The trade-off is creation of large skull base bone defects requiring reconstruction to re-establish barriers between the sino-nasal mucosa and subarachnoid space to prevent CSF leak and infection. A popular reconstructive technique is the local vascularized pedicled naso-septal flap, an option that may not always be possible when there is disruption of the vascular pedicle from multiple previous surgeries, adjuvant radiotherapy or extensive tumor infiltration. An alternative is the regional temporo-parietal fascial flap (TPFF) transposed via the trans-pterygoid route. We implemented a modification of this technique incorporating contralateral temporalis muscle at the tip of this flap and deeper vascularised pericranial layers within the pedicle to provide a more robust flap in selected cases.

Study design/methods

A retrospective review of two cases is presented with both patients having undergone multiple EEAs to resect skull base tumors with adjuvant radiotherapy, their postoperative courses complicated by recalcitrant CSF leaks resistant to multiple surgeries.

Results

Our patients had their persistent CSF fistulae repaired using infra-temporal transposition of the TPFF modified to include some of the contralateral temporalis muscle with optimisation of a vascular pedicle: a temporo-parietal temporalis myo-fascial flap (TPTMFF). Both CSF leaks resolved without further complication.

Conclusion

In situations where local flap repair to reconstruct skull-base defects following EEA may not be viable or has failed, a modified regional flap incorporating temporo-parietal fascia with a preserved vascular pedicle along with attached temporalis muscle plug may provide a robust alternative option.

Single Versus Double Hadad-Bassagasteguy Flap in Expanded Endoscopic Skull-Base Surgery

The reconstruction of dural defects, after endoscopic removal of skull-base lesions, remains challenging when a large defect or a high flow intraoperative cerebrospinal fluid (CSF) leak is observed. The aim of this study is to describe our preliminary experience with a double Hadad-Bassagasteguy (H-B) flap technique for skull-base repair, comparing its efficacy with the use of a single H-B flap in our series. A retrospective chart review was conducted on patients who underwent exclusive endoscopic endonasal skull-base surgery at our Referral Skull Base Center from December 2014 to January 2018. Data on patient demographics, pathology, preoperative and postoperative imaging, intraoperative findings, surgical route, defect size, reconstruction techniques and repair materials, were analyzed. Patients were divided into double and single H-B flap groups. In the single and double H-B groups, the postoperative CSF leak rates were 37.5% (6 of 16 patients) and 4.5% (1 of 22 patients), respectively. The difference between the two groups was statistically significant (p = 0.0470). In patients with defects > 4 cm or high-flow intraoperative CSF leakage related to the opening of the third ventricle, the double H-B flap was successfully placed with no occurrence of postoperative CSF leakage. The double H-B flap significantly reduced the postoperative CSF leakage rate after expanded transnasal skull-base surgery. Particularly in challenging cases, where a large skull-base defect or a high-flow intraoperative CSF leak was observed, this reconstructive method proved to be very effective, with no evidence of postoperative CSF fistulas.

Usefulness of endonasal flaps and grafts in skull base surgery. Consensus document

INTRODUCTION

Skull base reconstruction is one of the greatest challenges extended endonasal endoscopic surgery. Many grafts and flaps from the endonasal fossa have been demonstrated to be useful in the control of complications such a cerebrospinal fluid leaks. Review and analysis of these resources are necessary in skull base recontruction to improve outcomes.

OBJECTIVES

The target is to create a consensus document on the use of different endonasal flaps and grafts in the skull base surgery.

MATERIAL AND METHODS

Literature review of the most relevant free grafts and vascularized flaps from the endonasal fossa. Analysis using the Delphi method on the use of the different endonasal resources for endoscopic repair of skull base defects.

RESULTS

We obtained two results: 1) A selection of the most representative flaps and grafts from the endonasal fossa, describing origin, surface and indications, based on a literature review. 2) A consensus document, using Delphi methodology, with general considerations (2), recommendations (10) and limitations (6) of the different endonasal flaps and grafts.

CONCLUSIONS

We present the first consensus document in the field of extended endonasal endoscopic surgery using the Delphi method as a working tool. We highlight the usefulness of the nasoseptal flap together with other endonasal flaps and grafts for skull base reconstruction.

Radioanatomical Study of the Skull Base and Septum in Chinese: Implications for Using the HBF for Endoscopic Skull Base Reconstruction

Objective

Radioanatomy provides surgeons with different choices to prevent the failure of reconstruction caused by improper flap selection and the occurrence of CSF leakage or other severe complications. To establish a radioanatomical model, this study radioanatomically investigated the use of the Hadad-Bassagasteguy nasoseptal flap (HBF) in skull base reconstruction performed via the transethmoidal, transsphenoidal, and transclival approaches to provide preoperative guidance for the selection of approaches for skull base reconstruction and preparation of the HBF.

Methods

The computed tomography images of 40 Chinese adults were selected for the radioanatomical measurement of data related to the HBF and skull base reconstruction via the transethmoidal, transsphenoidal, and transclival approaches. The results were analyzed using radioanatomy combined with SPSS-based analysis.

Results

In the 40 patients, the area of the HBF exceeded that of skull base defects reconstructed via the transethmoidal approach by 10.21 ± 1.97 cm2, and the anterior margin width, posterior margin width, upper margin length, and lower margin lengths of the HBF all exceeded the corresponding values of skull base defects requiring reconstruction by at least 8.4 mm. The area of the HBF exceeded that of reconstructed skull base defects by an average of 10.72 ± 2.04 cm2. The area of the HBF exceeded that of skull base defects reconstructed via the transclival approach by 9.01 ± 2.87 cm2. The difference between the anterior margin width of the HBF and the middle width of skull base defects reconstructed via the transclival approach did not exceed 6 mm in only one case (5.4 mm).

Conclusion

In Chinese adults, the HBF can cover skull base defects reconstructed via the transethmoidal, transsphenoidal, and transclival approaches, permitting its use in skull base reconstruction performed via all three approaches. Radioanatomy can be used for preoperative guidance to plan surgery via the transethmoidal, transsphenoidal, and transclival approaches.

Endonasal Free Flap Reconstruction Combined With Draf Frontal Sinusotomy for Complex Cerebrospinal Fluid Leak: A Technical Report & Case Series

BACKGROUND

Frontal sinus cranialization with closure via bifrontal pericranial flaps is the gold standard for separating the nasofrontal recess from the intracranial cavity for posterior table defects. Despite the high success rate, cerebrospinal fluid (CSF) leak may persist and is particularly challenging when vascularized reconstructive options from the bicoronal incision are exhausted.

OBJECTIVE

To assess a novel endonasal technique using an adipofascial radial forearm free flap delivered to the frontal recess through a Draf sinusotomy to repair complex CSF leaks from the frontal sinus.

METHODS

A retrospective review of 3 patients (all male; ages 42, 43, and 69 yr) with persistent CSF leak despite frontal sinus cranialization and repair with bifrontal pericranium was performed. Etiology of injury was traumatic in 2 patients and iatrogenic in 1 patient after anaplastic meningioma treatment. To create space for the flap and repair the nasofrontal ducts, endoscopic Draf III (Case 1, 3) or Draf IIb left frontal sinusotomy (Case 2) was performed. The forearm flap was harvested, passed through a Caldwell-Luc exposure, and placed within the Draf frontal sinustomy. The flap vessels were tunneled to the left neck and anastomosed to the facial vessels by the mandibular notch.

RESULTS

Intraoperatively, the flaps were well-seated and provided a watertight seal. Postoperative hospital courses were uncomplicated. There were no new CSF leaks or flap necrosis at 12, 14, and 16 mo.

CONCLUSION

Endoscopic endonasal free flap reconstruction through a Draf procedure is a novel viable option for persistent CSF leak after failed frontal sinus cranialization.

Septal rhinopharyngeal flap: a novel technique for skull base reconstruction after endoscopic endonasal clivectomies

Endoscopic endonasal reconstruction techniques have improved CSF leak rates that were initially reported after surgery for cranial base and intradural lesions. However, wide surgical defects still pose a problem, especially if located in the clival region. The authors propose and describe a novel reconstruction technique they call a septal rhinopharyngeal flap (SRF) specifically designed to address this issue. The SRF is formed by three components of mucosa: 1) septal, 2) rhinopharyngeal roof, and 3) rhinopharyngeal posterior wall components, which allows for the coverage of the tuberculum/sellar region, midclivus, and lower clivus, respectively. A step-by-step procedure is described and its results analyzed in cases in which it has been used. The SRF was performed in 8 patients, which included diagnoses of 4 chordomas, 2 petroclival meningiomas, 1 invasive pituitary adenoma, and 1 chondrosarcoma. The size of the flap was considered optimal in all patients (100%). Postoperative MRI revealed contrast enhancement covering the entire surface of the flap. No CSF leaks were encountered after at least 1 postoperative year. The SRF is a novel vascularized reconstruction technique specifically indicated for wide endosanasal clivectomies focused on the middle clivus with caudal extension into the lower clivus and craniocervical junction, as well as rostral extensions into the tubercular or planum sphenoidale. This new reconstruction technique could be added to the skull base reconstruction armamentarium as a safe and optimal option.

Usefulness of endonasal flaps and grafts in skull base surgery. Consensus document

INTRODUCTION

Skull base reconstruction is one of the greatest challenges extended endonasal endoscopic surgery. Many grafts and flaps from the endonasal fossa have been demonstrated to be useful in the control of complications such a cerebrospinal fluid leaks. Review and analysis of these resources are necessary in skull base recontruction to improve outcomes.

OBJECTIVES

The target is to create a consensus document on the use of different endonasal flaps and grafts in the skull base surgery.

MATERIAL AND METHODS

Literature review of the most relevant free grafts and vascularized flaps from the endonasal fossa. Analysis using the Delphi method on the use of the different endonasal resources for endoscopic repair of skull base defects.

RESULTS

We obtained two results: 1) A selection of the most representative flaps and grafts from the endonasal fossa, describing origin, surface and indications, based on a literature review. 2) A consensus document, using Delphi methodology, with general considerations (2), recommendations (10) and limitations (6) of the different endonasal flaps and grafts.

CONCLUSIONS

We present the first consensus document in the field of extended endonasal endoscopic surgery using the Delphi method as a working tool. We highlight the usefulness of the nasoseptal flap together with other endonasal flaps and grafts for skull base reconstruction.

The Rostral Mucosa: The Door to Open and Close for Targeted Endoscopic Endonasal Approaches to the Clivus

BACKGROUND

Extended endoscopic endonasal approaches (EEAs) have progressively widened the armamentarium of skull base surgeons. In order to reduce approach-related morbidity of EEAs and closure techniques, the development of alternative strategies that minimize the resection of normal tissue and alleviate the use of naso-septal flap (NSF) is needed. We report on a novel targeted approach to the clivus, with incision and closure of the mucosa of the rostrum, as the initial and final step of the approach.

OBJECTIVE

To present an alternative minimally invasive approach and reconstruction technique for selected clival chordomas.

METHODS

Three cases of clival chordomas illustrating this technique are provided, together with an operative video.

RESULTS

The mucosa of the rostrum is incised and elevated from the underlying bone, as first step of surgery. Following tumor resection with angled scope and instruments, the mucosa of the sphenoid sinus (SS) is removed and the tumor cavity and SS are filled with abdominal fat. The mucosal incision of the rostrum is then sutured. A hangman knot is prepared outside the nasal cavity and tightened after the first stitch and a running suture is performed.

CONCLUSION

We propose, in this preliminary report, a new targeted approach and reconstruction strategy, applying to EEAs the classic concept of skin incision and closure for transcranial approaches. With further development in the instrumentations and visualization tools, this technique may become a valuable minimally invasive endonasal approach for selected lesions.

Novel Use of the Buccal Fat Pad for Sinocutaneous Fistulae Closure and a Review of Reconstructive Options

BACKGROUND

Sinocutaneous fistulae (SCF) are abnormal communications between the paranasal sinuses and the overlying skin. They may be difficult to manage due to facial geometry, scar contraction, and poor tissue vascularity. We describe a novel use of the buccal flap and review the literature to examine management options for this disease process.

METHODS

A PubMed/MEDLINE literature search was performed for studies published between January 1, 1950 and April 29, 2020 that describe management strategies for SCF. The clinical record, imaging, and operative reports were reviewed of the case in which the buccal fat flap was used in reconstruction.

RESULTS

A total of 359 articles were retrieved. After removing duplicate articles, non-English studies, animal studies, duplicate articles and studies that mentioned SCF without specific mention of management strategies, 51 articles were reviewed. Management paradigms throughout the articles include (1) removal of infection, (2) ensuring patency of sinus outflow tracts, (3) tensionless multilayered closure using well vascularized tissue, and (4) prevention or minimization of future risk factors for fistula formation.

CONCLUSION

This article informs surgeons on reconstructive options for sinocutaneous fistulae including a novel description of the buccal fat flap.

The "Parachute" Technique for the Endoscopic Repair of High-Flow Anterior Skull-Base CSF Leaks

OBJECTIVE

This study aims to assess the feasibility and reliability of our endoscopic trans-nasal technique for the repair of cribriform and sellar high-flow cerebrospinal fluid (CSF) leaks.

METHODS

A comparison between patients suffering from high-flow rhinorrhea and treated through a free grafting endoscopic technique or the "parachute" technique, our nasal packing proposal, was performed.

RESULTS

Thirty-three patients were included. The mean age was 52 years (range: 36-68 years). The etiology of the CSF leaks was iatrogenic in 16 cases (48.5%), traumatic in 5 cases (15.2%), spontaneous in 11 cases (33.3%), and related to anterior skull base tumors in 1 case (3%). The bone defect affected the sphenoidal sinus in 20 cases (60.6%), the cribriform plate of the ethmoid in 10 cases (30.3%), and both the sphenoid and ethmoid in 3 cases (9.1%). The mean size of bone defects was 8.5 ± 3.9 mm. The median follow-up was 28 (64) months. A CSF leak recurrence occurred in no cases treated with the parachute technique and in 3 cases that underwent conventional endoscopic treatments. The CSF leak recurrences were associated with 2 iatrogenic and 1 post-traumatic fistula. All the CSF leak recurrences underwent the parachute technique, not showing second recurrences.

CONCLUSIONS

Our results suggest that the parachute technique is simple, safe, and effective. We recommend it as an alternative treatment to vascular flaps for the treatment of high-flow and recurrent fistulas.

Mucosal resurfacing of the suprastructure maxillectomy cavity using nasal cavity mucosa flaps

OBJECTIVE

We analyzed clinical data of patients in which the suprastructure maxillectomy site was covered with nasal cavity mucosa flaps with or without free mucosa graft from the nasal septum, to determine the usefulness of this procedure.

PATIENTS AND METHODS

A total of four edentulous patients who had the suprastructure maxillectomy site covered using nasal cavity mucosa flaps with or without free mucosa graft from the nasal septum between 2014 and 2020, were analyzed.

RESULTS

All patients underwent suprastructure maxillectomy using the external approach. There were no major complications resulting from surgical intervention. Radiotherapy (RT) was performed in all patients after surgery. All nasal cavity mucosa flaps survived after RT. There was mild cheek retraction, but to a degree that was cosmetically tolerable in all patients. Local recurrence and distant metastasis to the orbit occurred in one patient. Among four patients, two patients died during follow-up, including one tumor related death and one death from old age.

CONCLUSION

We demonstrated that the use of nasal cavity mucosal flap to cover the suprastructure maxillectomy cavity was effective in improving the patient's quality of life by minimizing wound problems and facial contour changes such as cheek retraction despite postoperative RT.

A Novel Combined Transorbital Transnasal Endoscopic Approach for Reconstruction of Posttraumatic Complex Anterior Cranial Fossa Defect

The transorbital neuroendoscopic surgery (TONES), endoscopic transnasal skull base procedures, and the concept of multiportal minimal access neurosurgery are novel, rapidly evolving approaches in the management of complex skull base lesions. A 27-year-old male presented with a history of road traffic accident with nasal bleed, cerebrospinal fluid (CSF) rhinorrhea, and left eye deformity. There was left upper eyelid ecchymosis, orbital dystopia, left pupil was dilated, and fixed with no extraocular movements. The computed tomography scan showed basifrontal contusion and complex comminuted anterior cranial fossa (ACF) fracture involving left cribriform plate and left orbital roof with fracture fragment impinging on the superior rectus muscle with suspicious orbital CSF leak. There was no improvement with conservative management. Hence, a novel combined TONES, transnasal endoscopic multiportal surgery was undertaken for the removal of fracture fragments and multi-layered closure of the complex ACF defect. The patient had a complete resolution of orbital dystopia and visual loss with no evidence of CSF leak postoperatively.

Advances in vascularized flaps for skull base reconstruction

PURPOSE OF REVIEW

Advances in anterior skull base surgery have resulted in the increasing diversification of reconstructive techniques. New vascularized flaps have been suggested in the last years, some quite similar, whereas new uses and applications have been suggested for some vascularized flaps, which have already established their value over the last decades. In this article, we describe the developments in skull base reconstruction with vascularized flaps and analyse the international experience in the use of vascularized flaps published with a focus on the last 18 months.

RECENT FINDINGS

Over the past 18 months, a number of novel or modified vascularized intranasal flaps have been described, focusing on reconstruction of larger defects, the medial orbital wall, the anterior skull base (septal flip-flap) and dissection of the nasoseptal flap from the SPA foramen. Extranasal vascularized flaps, which have been around for a long time, still have their rightful place in skull base reconstruction and have recently been adjusted for endoscopic use.

SUMMARY

We present an overview of the latest developments in vascularized flaps (intranasal and extranasal), their new implications, their modifications and complications or predictions of viability.

Vascular pedicled flaps for skull base defect reconstruction

OBJECTIVE

Techniques for reconstruction of skull base defects have advanced greatly since the introduction of the vascular pedicled nasoseptal flap in 2006. The objective of this review is to assess the current state of the field by examining both intranasal and extranasal techniques of vascular pedicled skull base defect repair, their indications and success rates, and novel techniques that are currently under investigation.

METHODS

A review of the literature describing the use of vascular pedicled flaps in skull base defect reconstruction was conducted using PubMed and Google Scholar.

RESULTS

The nasoseptal flap remains the most widely used vascular pedicled flap for endoscopic repair of skull base defects. Its ease of harvest, wide arch of rotation, and high success rates make it a popular choice among surgeons. Several variations including a "rescue" nasopseptal flap have been developed. Other less commonly used pedicled intranasal flaps include the middle turbinate flap and the posterior pedicled inferior turbinate flap. Additionally, several novel vascular pedicled flaps have been developed and tested in small cohorts of patients. Extranasal flaps such as the pericranial flap and the temporoparietal fascia flap are used less frequently than intranasal flaps. However, they remain valuable options for reconstruction in certain situations.

CONCLUSION

Advancements continue to be made in the field of skull base defect reconstruction using vascular pedicled flaps. Though the nasoseptal flap remains the most widely utilized option, additional intranasal techniques continue to be developed and tested to optimize surgical outcomes and patient care.

LEVEL OF EVIDENCE

NA.

Design of a temporoparietal fascial flap after a spontaneous nasal fistula unresolved by conventional approaches

We report the surgical management of a spontaneous and recurrent nasal fistula using a temporoparietal fascial flap for definitive treatment after several failed attempts to close the fistula by conventional approaches. Two formalin-fixed cadaveric human heads were also dissected to study the anatomy and surgical technique involved in the design of the temporoparietal fascial flap.

Modified Posterior Pedicle Middle Turbinate Flap: An Additional Option for Skull Base Resurfacing

OBJECTIVES/HYPOTHESIS

Although the Hadad-Bassagusteguy flap represents the first choice for middle and posterior skull base reconstruction and coverage of exposed bony areas, in some cases it is unavailable. The aim of this study is to describe, as an alternative option in selected cases, a modified posterior pedicle middle turbinate flap (mPPMTF) extended to the lacrimal area. Anatomical features, step-by-step harvesting technique, and surgical applications are presented.

STUDY DESIGN

Anatomic dissection study and case report.

METHODS

Four mPPMTFs were raised in two fresh-frozen cadaver heads. A study of the vascular supply and measurements of length, width, and area of the flap were performed. The ability of the flap to cover the ventral skull base, particularly the upper clivus area, was tested. A clinical case in which an mPPMTF was used for clivus resurfacing after osteoradionecrosis is reported.

RESULTS

The vascular supply of the mPPMTF was identified as the middle turbinate branch of the sphenopalatine artery. The flap had a mean length of 6.92 cm, mean maximum width of 1.08 cm, and mean total area of 5.33 cm² . The flap was able to reach the upper clivus, with a clival coverage ratio of 70.66%. In the clinical case, good surgical outcomes were observed, with accelerated re-epithelization without complications.

CONCLUSIONS

The mPPMTF represents an alternative to the Hadad-Bassagusteguy flap for posterior cranial fossa and nasopharynx resurfacing. The main drawbacks are its technically demanding and time-consuming harvesting.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E767-E774, 2021.

ICAR: endoscopic skull-base surgery

BACKGROUND

Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS).

METHODS

Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated.

CONCLUSION

A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

Surgical management of craniopharyngiomas in adult patients: a systematic review and consensus statement on behalf of the EANS skull base section

BACKGROUND AND OBJECTIVE

Craniopharyngiomas are locally aggressive neuroepithelial tumors infiltrating nearby critical neurovascular structures. The majority of published surgical series deal with childhood-onset craniopharyngiomas, while the optimal surgical management for adult-onset tumors remains unclear. The aim of this paper is to summarize the main principles defining the surgical strategy for the management of craniopharyngiomas in adult patients through an extensive systematic literature review in order to formulate a series of recommendations.

MATERIAL AND METHODS

The MEDLINE database was systematically reviewed (January 1970-February 2019) to identify pertinent articles dealing with the surgical management of adult-onset craniopharyngiomas. A summary of literature evidence was proposed after discussion within the EANS skull base section.

RESULTS

The EANS task force formulated 13 recommendations and 4 suggestions. Treatment of these patients should be performed in tertiary referral centers. The endonasal approach is presently recommended for midline craniopharyngiomas because of the improved GTR and superior endocrinological and visual outcomes. The rate of CSF leak has strongly diminished with the use of the multilayer reconstruction technique. Transcranial approaches are recommended for tumors presenting lateral extensions or purely intraventricular. Independent of the technique, a maximal but hypothalamic-sparing resection should be performed to limit the occurrence of postoperative hypothalamic syndromes and metabolic complications. Similar principles should also be applied for tumor recurrences. Radiotherapy or intracystic agents are alternative treatments when no further surgery is possible. A multidisciplinary long-term follow-up is necessary.

Combined Nasoseptal and Inferior Turbinate Flap for Reconstruction of Large Skull Base Defect After Expanded Endonasal Approach: Operative Technique

BACKROUND

Increasing indications for endoscopic endonasal approaches have led neurosurgeons to develop new reconstruction techniques for larger skull base defects. Vascularized grafts have been a great adjunction to reduce the rate of cerebrospinal fluid leak and can also be used to cover exposed critical structures such as the internal carotid artery. The nasoseptal flap and the inferior or middle turbinate flap are thus widely used in endoscopic skull base surgery, but may be insufficient for very large defects.

OBJECTIVE

To present a new mucosal flap used to cover large skull base defects in which the mucosa of the inferior turbinate, inferior meatus, nasal floor, and nasal septum is harvested in 1 piece keeping both vascular pedicles intact (inferior turbinate and septal arteries).

METHODS

We describe a surgical technique to harvest a combined inferior turbinate-nasoseptal flap.

RESULTS

Technical pearls and surgical pitfalls are described through 2 clinical cases in which the nasoseptal mucosa was partially damaged during a previous surgery, rendering the nasoseptal flap insufficient by itself. The flap is harvested thanks to 2 mucosal cuts: a first circular cut around the choanal arch and the junction between the hard and the soft palate, and a second one combining classical cuts of the nasoseptal flap and the inferior turbinate flap.

CONCLUSION

The inferior turbinate-nasoseptal flap can be a useful alternative in patients whose septal mucosa was partially damaged and/or with very large postoperative skull base defects.

Pathological Features of Free Graft and Pedicled Flap in the Nasal Cavity: An Animal Study

OBJECTIVES/HYPOTHESIS

Recent developments in reconstructive techniques for mucosal defects using mucoperiosteal materials have enabled rapid recovery of physiological function after endoscopic sinus surgery. Clinical trials have described the advantages, disadvantages, and different outcomes of free graft and pedicled flap, which, respectively, sacrifice or preserve blood flow. However, histological changes, that affect the postoperative outcomes after reconstruction, remain unclear. We created an animal model for the reconstruction of mucosal defects using free grafts and pedicled flaps, and evaluated them histologically.

STUDY DESIGN

Animal study.

METHODS

We created mucosal defects in the left nasal septum of 20 rabbits and performed reconstruction with free grafts and pedicled flaps. The distribution of ciliary and goblet cells at the reconstruction site was evaluated after 7 and 28 days using hematoxylin and eosin-stained sections to calculate the Ciliary Cell Index and Goblet Cell Index. The severity of inflammation was assessed using the Cartilage Inflammatory Cell Score.

RESULTS

Crusting and changes in the mucosal morphology at the reconstruction site occurred only in the free graft group. In addition, the pedicled flap group had significantly greater preservation of ciliary and goblet cells and less inflammatory cell infiltration into the septal cartilage (P < .05) than the free graft group.

CONCLUSIONS

After reconstruction procedures for mucosal defects, histopathological differences were observed between the free graft and pedicled flap. Reconstruction with pedicled flaps had advantages including preservation of healthy mucosal epithelium and suppression of inflammation on the reconstruction site. This indicated that reconstruction with pedicled flaps might have advantages over that with free grafts.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:E428-E433, 2021.

Vascular Anatomy of the Inferior Turbinate and Its Clinical Implications

BACKGROUND

Published reports on the vascular anatomy of the inferior turbinate (IT) are limited. Historical papers report the IT artery as a tributary off the posterior lateral nasal artery (PLNA), but this has not been our clinical experience.

OBJECTIVE

The purpose of this study was to examine the arterial blood supply to and the branching pattern within the IT. We discuss this is the context of IT surgery and relate it to postoperative bleeding complication rates.

METHODS

Endoscopic dissection was performed on 16 cadaver heads (24 sides) to determine the origin of the IT artery. Intraoperative surgical videos were analyzed in 50 patients to uncover the vascular branching pattern within the IT. A retrospective review of bleeding complications in patients undergoing IT reduction surgery was also conducted.

RESULTS

In 17 of 24 sides (70.8%), the IT artery arose either exclusively (54.2%) or partly (16.6%) off the descending palatine artery (DPA). As a branch off the DPA, the IT artery exited the pterygopalatine fossa through a foramen located 7.7 ± 3.0 mm from posterior edge of the IT, 8.4 ± 3.1 mm above the nasal floor and 1.6 ± 2.1 mm below the insertion of the IT bone onto the lateral nasal wall. The mean number of arteries cascading within the IT was 2.7 ± 0.5. Moreover, 112 patients underwent IT reduction surgery and 2 (1.8%) experienced postoperative epistaxis.

CONCLUSION

The IT artery has major contributions from the DPA. Most commonly 3 arteries branch within the IT. Knowledge of this vascular anatomy may minimize bleeding associated with IT reduction surgery.

Reconstruction of skull base bone defects using an in situ bone flap after endoscopic endonasal transplanum-transtuberculum approaches

PURPOSE

The creation of bone flaps which can be later repositioned and fixed in situ for repairing the bone defects during the endoscopic endonasal approaches (EEAs)-similar to transcranial craniotomies-is still a challenge. We present an in situ bone flap (ISBF) closure for the repair of bone defects after endoscopic endonasal transplanum-transtuberculum approaches (EETAs).

METHODS

A retrospective analysis of consecutive patients who underwent the EETAs between January 2016 and February 2019 was performed. According to whether or not to use ISBF for skull base reconstruction, these patients were divided into the ISBF group or the non-ISBF group.

RESULTS

Of 47 patients in the ISBF group, only one patient (2.1%) developed postoperative cerebrospinal fluid (CSF) leakage, yielding a significantly lower leakage rate in the ISBF group than in the non-ISBF group (6 of 38, 15.8%, P = 0.042). Besides, when only comparing cases of hydrocephalus in the two groups, the CSF leakage rate in the ISBF group was 8.3% (1/12), which was still significantly lower than that in the non-ISBF group (62.5%, 6/8) (P = 0.018). Postoperative CSF leakages in both groups were successfully treated with lumbar drainage alone, and no cases of injury to the internal carotid arteries or optic nerves occurred in either group.

CONCLUSIONS

An ISBF closure similar to transcranial craniotomies with repositioning bone flap in situ-is feasible, safe, and reliable. The ISBF closure combining with a pedicled nasoseptal flap (PNSF) provides the cranial base surgeon with an additional repair method that has demonstrated effectiveness at facilitating a more stable and durable reconstruction and reducing CSF leaks.

Lateral nasal wall flap for endoscopic reconstruction of the skull base: anatomical study and clinical series

BACKGROUND

The lateral nasal wall (LNW) flap provides vascularized endonasal reconstruction primarily in revision surgery. Although the harvesting technique and reconstructive surface have been reported, the arterial supply to the LNW flap and its clinical implications is not well defined. This study presents anatomical dissections to clarify the vascular supply to this flap, and the associated clinical outcomes from this reconstructive technique.

METHODS

The course and branching pattern of the sphenopalatine artery (SPA) to the LNW were studied in 6 vascular latex-injected heads (11 LNW flaps total). Patients undergoing an LNW flap since 2008 were identified and the underlying pathology, indication, flap viability, and clinical outcomes were retrospectively analyzed.

RESULTS

The inferior turbinate artery arises from the LNW artery and divides into 2 branches at the most posterior aspect of the inferior turbinate bone. A smaller-caliber superficial branch travels anteriorly and branches to the LNW. A larger dominant branch travels into the inferior meatus and tangentially supplies the nasal floor. Twenty-four patients with sellar or posterior cranial fossa (PCF) defects were reconstructed with an LNW flap. Postoperative contrast enhancement of the LWN flap was identified in 95.5% of cases. Postoperative cerebrospinal fluid (CSF) leaks were identified in 6 cases.

CONCLUSION

Blood supply to the nasal floor by the dominant inferior meatus branch is more robust than the supply to the anterior LNW by the superficial arterial branch. The LNW flap is the preferred vascularized reconstructive option to the PCF and sella in the absence of a nasoseptal flap (NSF).

Various modifications of a vascularized nasoseptal flap for repair of extensive skull base dural defects

OBJECTIVE

Endonasal surgery of the skull base requires watertight reconstruction of the skull base that can seal the dural defect to prevent postoperative CSF rhinorrhea and consequent intracranial complications. Although the incidence of CSF leakage has decreased significantly since the introduction in 2006 of the vascularized nasoseptal flap (the Hadad-Bassagasteguy flap), reconstruction of extensive skull base dural defects remains challenging. The authors describe a new, modified vascularized nasoseptal flap for reconstruction of extensive skull base dural defects.

METHODS

A retrospective review was conducted on 39 cases from 2010 to 2017 that involved reconstruction of the skull base with an endonasal vascularized flap. Extended nasoseptal flaps were generated by adding the nasal floor and inferior meatus mucosa, inferior turbinate mucosa, or entire lateral nasal wall mucosa. The authors specifically highlight the surgical techniques for flap design and harvesting of these various modifications of the vascularized nasoseptal flap.

RESULTS

Thirty-nine endonasal vascularized flaps were used to reconstruct skull base defects in 37 patients with nonsurgical or postoperative CSF rhinorrhea. Of the 39 procedures, extended nasoseptal flaps were used in 5 cases (13%). These included 2 extended nasoseptal flaps including the inferior turbinate mucosa and 3 extended nasoseptal flaps including the entire lateral nasal wall mucosa. These 5 extended nasoseptal flaps were used in patients who had nonsurgical CSF rhinorrhea due to extensive skull base destruction by invasive pituitary tumors. All flaps healed completely and sealed off the CSF leaks. Olfactory function slightly decreased in the 3 patients with extended nasoseptal flaps including the entire lateral nasal wall mucosa. One patient experienced nasolacrimal duct obstruction, which was treated by dacryocystorhinostomy. The authors encountered no wound complication in this series, while crusting at the donor site required daily nasal toilette and frequent debridement until the completion of mucosalization, which usually takes 8 to 12 weeks after surgery.

CONCLUSIONS

Extended nasoseptal flaps are a reliable and versatile option that can be used to reconstruct extensive skull base dural defects resulting from destruction by large invasive tumors or complex endoscopic endonasal surgery. An extended nasoseptal flap that includes the entire lateral nasal wall mucosa (360° flap) is the largest endonasal vascularized flap reported to date and may be an alternative for the reconstruction of extensive skull base defects while avoiding the need for additional external approaches.

Does 3D volumetric analysis predict the reach of endoscopically harvested buccal fat pad flap

OBJECTIVES

To determine if the volume of buccal fat, ascertained by computed tomography (CT) scanning, would correspond to surface area and reach (length and width) of the flap intraoperatively to aid in the reconstruction of selected skull base defects.

METHODS

Cadaveric study of five specimens, 10 sides. Methods CT imaging and evaluation using the Osirix 9 software (Pixmeo; Bernex, Switzerland). of cadaveric heads to calculate the volume of the buccal fat bilaterally. The flap was then harvested endoscopically. Measurements were taken. Two heads were also dissected via a transfacial approach.

RESULTS

The volume of the buccal fat pad (BFP) as well as the maximum length and width of the endoscopically harvested flap were documented. There was a positive correlation shown between the calculated volume of the BFP based on CT imaging and the dissected length and width of the flap (Pearson correlation, r = 0.83 and r = 0.80, respectively). The transfacial dissection demonstrated the lobes of the BFP well, showing that most of the endoscopic mobilization of the BFP was limited to the posterior lobe, in particular to the temporalis and pterygoid components, with minimal displacement of the superficial components. This minimized the risk of visibly hollowing the buccal fullness.

CONCLUSION

Preoperative calculation of the CT-based volume of the BFP correlates positively with the intraoperative maximum reach of the flap for both length and width. Whereas the volume may be lower in some instances, the BFP would still have adequate reach to provide coverage for the lower and mid-clival region in most patients.

LEVEL OF EVIDENCE

NA. Laryngoscope, 130:1670-1673, 2020.

Sellar Defect Reconstruction with Vascularized Superior Turbinate Mucosal Flaps in Endonasal Endoscopic Transsellar Approach

BACKGROUND

The pedicled nasoseptal flap (NSF) constitutes the primary reconstructive option for most skull base defects in endonasal endoscopic approaches. The superior nasal turbinate (ST) has received little attention. We report our preliminary experience with the use of the ST mucosal flap in selected cases.

METHODS

We performed a retrospective review of patients who underwent endonasal endoscopic approaches and identified 9 patients who were reconstructed with vascularized ST mucosal flaps as part of a double-layer or triple-layer reconstruction. When there was no intraoperative cerebrospinal fluid (CSF) leak, we used a double-layer technique. If there was an intraoperative CSF leak, regardless of the quality of leakage, we preferred a triple-layer repair technique. In patients with high-flow leaks, triple-layer repair was performed using only autologous tissue grafts and flaps.

RESULTS

Intraoperative CSF leaks were noted in 7 of 9 patients. Among them, 4 patients had low-flow CSF leaks (grade 1 and 2) and 3 patients had high-flow CSF leaks (grade 3). All reconstructions had complete defect coverage with the ST flaps and NSFs were preserved. All the flaps were viable at 4 weeks without a CSF leak or complication at the reconstruction site. There was no contraction or partial loss of the flap. After a mean follow-up period of 9 months, none of the patients required a flap revision, developed a mucocele, infection, or other complication.

CONCLUSIONS

An ST flap can be used for the vascularized reconstruction of sellar defects if it is bilaterally available. This option should not be overlooked and wasted.

Endoscopic reconstruction of large anterior skull base defects with opening of the sellar diaphragm. Experience at a tertiary level university hospital

Background

The indications for expanded endoscopic transnasal approaches continue to increase, with more complex skull base defects needing to be repaired. This study reviews the management of large anterior skull base defects with opening of the sellar diaphragm.

Method

A prospective analysis of endonasal endoscopic surgery carried out at Son Espases University Hospital between January 2013 and December 2018 was performed. The analysis included only the cases with a significative intra-operative cerebrospinal fluid leak. In all cases, reconstruction was performed by combining the gasket seal technique with a pedicled mucosal endonasal flap.

Results

Twenty-eight patients were included. The mucoperiosteal nasoseptal flap, the lateral wall flap and the middle turbinate flap were used in 13, 8 and 7 patients, respectively, combined with the gasket seal technique. One case of post-operative cerebrospinal fluid leak was observed (3.57 per cent).

Conclusion

The combination of a gasket seal with an endonasal mucosal flap is an excellent technique for repairing large anterior skull base defects.

Posterior nasoseptal flap in the reconstruction of skull base defects following endonasal surgery

OBJECTIVE

To study the clinical outcomes of a posterior nasoseptal flap used in the endonasal reconstruction of anterior skull base defects.

METHODS

The early harvested flap was used to reconstruct anterior skull base defects in patients with high-flow on-table cerebrospinal fluid leak. Post-operatively, the patients were analysed for cerebrospinal fluid leak and bleeding.

RESULTS

Of the 100 patients, 87 had macro defects while 13 had micro defects. Non-secretary lesions were present in 60 patients, while secretary lesions were present in 40 patients. Cerebrospinal fluid leak was present in all the patients undergoing surgery, and the majority of them had a lumbar drain fitted. Post-operatively, two patients experienced bleeding and only two patients had a cerebrospinal fluid leak.

CONCLUSION

The use of a posterior nasoseptal flap for reconstruction of the anterior skull base amongst patients with a high-flow intra-operative cerebrospinal fluid leak can help prevent post-operative cerebrospinal fluid leak. Its applicability to wide patient profiles, with respect to age, size of defect and diagnosis, make it a versatile choice for reconstruction after endonasal anterior skull base surgical procedures.

Septal Flip Flap for Anterior Skull Base Reconstruction After Endoscopic Transnasal Craniectomy: Long-Term Outcomes

BACKGROUND

Endoscopic endonasal anterior skull base malignant sinonasal tumor resection and reconstruction remains a challenge. We describe our septal flip flap (SFF) reconstruction, a new surgical technique for repairing anterior skull base defects and report our outcomes.

METHODS

We retrospectively reviewed the clinical data of 24 patients who underwent skull base reconstruction using a SFF following endoscopic resection with transnasal craniectomy. We raise the SFF from the contralateral nasal septum based on the septal branches of the anterior and posterior ethmoidal arteries; the SFF is then rotated laterally for anterior skull base reconstruction after transnasal resection with craniectomy.

RESULTS

The SFF was used for multiple tumor types including, most commonly, intestinal-type adenocarcinoma, followed by olfactory neuroblastoma, squamous cell carcinoma, sinonasal undifferentiated carcinoma, and other types. All of the cases had either preoperative or postoperative radiation therapy. All flaps remained viable postoperatively. Postoperatively, nasal crusting was significantly reduced with faster healing of the surgical cavity.

CONCLUSIONS

The SFF adds to the clinical armamentarium the opportunity to provide vascularized mucosal coverage extending from the frontal recess back to the planum sphenoidalis. The use of SFF requires careful consideration when dealing with paranasal sinus cancers so as not to infringe oncologic principles.

Side-Door Temporoparietal Fascia Flap: A Novel Strategy for Anterior Skull Base Reconstruction

BACKGROUND

The armamentarium for anterior skull base (ASB) reconstruction includes a variegate spectrum of grafts, endonasal pedicled flaps, regional pedicled flaps, and free flaps, which are selected to face specific scenarios. The use of a vascularized flap in case of large ABS defects ensures an adequate blood supply. The aim of this study was to evaluate the possible role of temporoparietal fascia flap (TPFF) in ASB reconstruction.

METHODS

Eight fresh-frozen head specimens were dissected to evaluate the adequacy of TPFF and pericranial flap (PF) for the reconstruction of ASB defects. The percentage of coverage of the ASB was calculated for TPFF and PF. An anatomic-radiologic analysis was performed to provide useful practical information for flap harvesting and positioning.

RESULTS

The TPFF was easily transposed to the ABS defect through an epidural corridor; the edges of the TPFF were successfully placed in the intradural space, in the epidural space, or on the extracranial surface of the ABS defect. The PF was particularly adequate for median defects, and the TPFF was shown to be useful also in cases with paramedian-supraorbital extension. The median percentage of coverage of the ASB was significantly higher for TPFF (85.1%) than PF (65.7%) (P = 0.018).

CONCLUSIONS

The supraorbital epidural corridor is a possible novel pathway for transposition of the TPFF for ASB reconstruction. Side-door TPFF was shown to be an ideal choice for large ASB defect with lateral supraorbital extension and could be useful in the scenario of salvage reconstruction for recurrent ABS cerebrospinal fluid leak.

Watertight Robust Osteoconductive Barrier for Complex Skull Base Reconstruction: An Expanded-endoscopic Endonasal Experimental Study

Endoscopic skull base reconstruction (ESBR) following expanded-endoscopic endonasal approaches (EEA) in high-risk non-ideal endoscopic reconstructive candidates remains extremely challenging, and further innovations are still necessary. Here, the aim is to study the reconstructive knowledge gap following expanded-EEA and to introduce the watertight robust osteoconductive (WRO)-barrier as an alternative durable option. Distinctively, we focused on 10 clinical circumstances. A 3D-skull base-water system model was innovated to investigate the ESBR under realistic conditions. A large-irregular defect (31 × 89 mm) extending from the crista galli to the mid-clivus was achieved. Then, WRO-barrier was fashioned and its tolerance was evaluated under stressful settings, including an exceedingly high (55 cmH₂O) pressure, with radiological assessment. Next, the whole WRO-barrier was drilled to examine its practical-safe removal (simulating redo-EEA) and the whole experiment was repeated. Finally, WRO-barrier was kept into place to value its 18-month long-term high-tolerance. Results in all experiments of WRO-barriers were satisfactorily fashioned to conform the geometry of the created defect under realistic circumstances via EEA, tolerated an exceedingly high pressure without evidence of leak even under stressful settings, resisted sudden-elevated pressure, and remained in its position to maintain long-term watertight seal (18 months), efficiently evaluated with neuroimaging and simply removed-and-reconstructed when redo-EEA is needed. In conclusion, WRO-barrier as an osteoconductive watertight robust design for cranial base reconstruction possesses several distinct qualities that might be beneficial for patients with complex skull base tumours.

Endoscopic Endonasal Approaches for Treatment of Craniovertebral Junction Tumours

Tumours involving the craniovertebral junction (CVJ) are challenging because of their local invasiveness and high recurrence rates, as well as their proximity to critical neurovascular structures and the difficulty of reconstructing the resulting skull base defect at this site. Several surgical techniques are currently available to access these lesions, including the far lateral, extreme lateral, direct lateral, transcervical, transoral and transnasal approaches. In this paper, application of the endoscopic endonasal approach (EEA) in the treatment of CVJ tumours is analysed. The indications, contraindications, preoperative workup, step-by-step surgical technique, skull base reconstruction options and postoperative management are described. The advantages and limitations of the EEA are also discussed. Finally, a systematic review of the literature is provided to elucidate the levels of evidence supporting the use of the EEA in this field. Employment of this approach to the CVJ has contributed to high success rates in achieving gross total resection of tumours and improvement in neurological symptoms. Intraoperative and postoperative complication rates are acceptable, with cerebrospinal fluid leakage being the major concern (with a 17-25% incidence). Moreover, in comparison with traditional approaches to the CVJ, the EEA provides lower rates of postoperative dysphagia and respiratory complications. Use of the EEA for treatment of CVJ tumours appears to be a rational alternative to the conventional transoral, transcranial and transcervical approaches in selected cases. Multidisciplinary teamwork including different specialists-such as medical and radiation oncologists, radiologists, otorhinolaryngologists and neurosurgeons-is strongly recommended for the purpose of offering the best treatment strategy for the patient.

[Tactics of reconstructive closure of basal defects after resection of midline tumors of the anterior skull base (a literature review)]

The purpose of this review is to analyze the techniques used to reconstruct midline defects in the anterior skull base after transcranial and endoscopic endonasal resection of skull base tumors. We provide brief information on the technique for preparing various flaps, indications and contraindications, and advantages and disadvantages. We analyze the international experience in the use of vascularized and non-vascularized flaps as well as the existing algorithms for reconstruction of complex defects of the midline structures of the skull base. The literature data demonstrate the absence of a conventional tactics of reconstructive closure of the discussed defects. To resolve this issue, a meta-analysis in combination with an original prospective study is required.

Endoscopic endonasal double flap technique for reconstruction of large anterior skull base defects: technical note

Introduction

One of the main concerns in endoscopic endonasal approaches to the skull base has been the high incidence and morbidity associated with cerebrospinal fluid leaks. The introduction and routine use of vascularized flaps allowed a marked decrease in this complication followed by a great expansion in the indications and techniques used in endoscopic endonasal approaches, extending to defects from huge tumours and previously inaccessible areas of the skull base.

Objective

Describe the technique of performing endoscopic double flap multi-layered reconstruction of the anterior skull base without craniotomy.

Methods

Step by step description of the endoscopic double flap technique (nasoseptal and pericranial vascularized flaps and fascia lata free graft) as used and illustrated in two patients with an olfactory groove meningioma who underwent an endoscopic approach.

Results

Both patients achieved a gross total resection: subsequent reconstruction of the anterior skull base was performed with the nasoseptal and pericranial flaps onlay and a fascia lata free graft inlay. Both patients showed an excellent recovery, no signs of cerebrospinal fluid leak, meningitis, flap necrosis, chronic meningeal or sinonasal inflammation or cerebral herniation having developed.

Conclusion

This endoscopic double flap technique we have described is a viable, versatile and safe option for anterior skull base reconstructions, decreasing the incidence of complications in endoscopic endonasal approaches.

Survey of endoscopic skull base surgery practice patterns among otolaryngologists

Background

Endoscopic skull base surgery (ESBS) is a rapidly expanding field. Despite divergent reported preferences for reconstructive techniques and perioperative management, limited data exist regarding contemporary practice patterns among otolaryngologists performing ESBS. This study aims to elucidate current practice patterns, primarily the volumes of cases performed and secondarily a variety of other perioperative preferences.

Methods

An anonymous 32‐item electronic survey examining perioperative ESBS preferences was distributed to the American Rhinologic Society membership. Statistical significance between variables was determined utilizing Student t, chi‐square, and Fisher exact tests.

Results

Seventy otolaryngologists completed the survey. The effective response rate was approximately 22.5%. Sixty percent of respondents were in full‐time academic practice and 70% had completed rhinology/skull base fellowships. Annually, 43.3 mean ESBS cases were performed (29.1 private practice vs. 52.9 academic practice, P = .009). Academic practice averaged 24.1 expanded cases versus only 11 in private practice (P = .01). Of respondents, 55.7% stood on the same side as the neurosurgeon and 72.9% remained present for the entire case. Current procedural terminology coding and antibiotic regimens were widely divergent; 31.4% never placed lumbar drains preoperatively, while 41.4% did so for anticipated high‐flow cerebrospinal fluid leaks. While considerable variation in reconstructive techniques were noted, intradural defect repairs utilized vascularized flaps 86.3% of the time versus only 51.3% for extradural repairs (P < 0.001). Major complications were rare. Postoperative restrictions varied considerably, with most activity limitations between 2–8 weeks and positive airway pressure use for 2–6 weeks. Most respondents started saline irrigations 0–2 weeks postoperatively.

Conclusions

Based on responses from fellowship‐ and non‐fellowship‐trained otolaryngologists in various practice settings, there remains considerable variation in the perioperative management of patients undergoing ESBS.

Level of Evidence

5

Endoscopic pericranial flap design for the restoration of nasal mid-vault lining defects

Despite progress made in nasal reconstruction, the restoration of a large defect, including the whole septum and mid-nasal vault structures, remains a challenge. The pericranial flap (PCF) is used widely for the reconstruction of anterior cranial fossa defects. This article presents a surgical technique for nasal lining restoration with an endoscopic PCF design. This technique was used in patients with huge intranasal tumours. Two patients with nasal eosinophilic angiocentric fibrosis were treated. The structural involvement was similar in each case. The tumour was resected completely by combined endoscopic and external methods through an open rhinoplasty approach. The resulting defect included the whole nasal septum, bilateral upper lateral cartilage, and the entire mid-nasal vault mucosal lining. Reconstruction was achieved by endoscopic PCF design for internal lining reconstruction and rib cartilage for framework repair. The first patient was followed up for 18months and the second for 8months. No infection occurred in the postoperative period. Framework stability and texture were good, and both nasal shapes were acceptable. In conclusion, this endoscopic PCF approach for restoring the internal nasal lining appears to be a good choice in selected cases.