Endoscopic transpterygoid approach to the lateral sphenoid recess: surgical approach and clinical experience

Endoscopic Transpterygoid Repair of Sphenoid Sinus Meningocele: A Comprehensive Case Report and Literature Review

We report a challenging and uncommon case involving a 53-year-old Japanese man with cerebrospinal fluid (CSF) leakage caused by a meningocele in the lateral recess of the sphenoid sinus. Our innovative treatment approach involved a combination of transpterygoid and endoscopic modified medial maxillectomy techniques, with special emphasis on the preservation of the sphenopalatine artery. This strategic preservation was pivotal to the successful use of the ipsilateral nasoseptal flap for reconstruction, which played a crucial role in the prevention of postoperative CSF leakage. Otolaryngologists and neurosurgeons collaborated to perform the bath-plugging technique; effective collaboration was instrumental to the success of the procedure. This report highlights significant advancement from conventional frontal craniotomy to a more sophisticated endoscopic technique, shows the importance of meticulous surgical planning and execution, emphasizes careful preservation of critical anatomical structures during complex neurosurgical and otolaryngological procedures, and underscores the evolving landscape of surgical approaches for managing complex medical conditions.

Prelacrimal-Transmaxillary Approach to Lateral Sphenoid Recess Skull Base Defects

The lateral recess of a well-pneumatized sphenoid sinus is challenging to access surgically. Traditional methods require the use of multiple angled endoscopes and curved instruments which may limit visualization. We describe a prelacrimal-transpterygoid/maxillary approach which offers direct access to this region with a 0° endoscope. Laryngoscope, 2024.

Radiologic evaluation of the Vidian canal in the pediatric population

PURPOSE

This examination aimed to display the size and topographic position of the Vidian canal (VC) in normal children.

METHODS

180 pediatric subjects aged 1-18 years were included this computed tomography examination. The distances of VC to certain landmarks, and VC length were measured. The locations of VC according to the sphenoid sinus, and the medial plate of pterygoid process were classified as three types, separately.

RESULTS

The distances of VC to the vomerine crest, midsagittal plane, round foramen, and the superior wall of sphenoid sinus were measured as 12.68 ± 3.17 mm, 10.76 ± 2.52 mm, 8.62 ± 2.35 mm, and 14.16 ± 5.00 mm, respectively. The length and angle of VC were measured as 12.00 ± 2.52 mm, and 16.60 ± 9.76°, respectively. According to the sphenoid bone, VC location was identified as Type 1 in 113 sides (47.5%), as Type 2 in 70 sides (29.4%), and as Type 3 in 55 sides (23.1%). According to the medial plate of pterygoid process, VC location was identified as Type A in 274 sides (76.1%), as Type B in 55 sides (15.3%), and as Type C in 31 sides (8.6%). VC location types correlated with pediatric ages, but not sex or side.

CONCLUSION

With advancing pediatric age, the protrusion of VC into the sphenoid sinus increases, and VC shifts from medial to lateral side of the medial plate of pterygoid process.

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Endoscopic Endonasal and Endoscopic-Assisted Transmaxillary Transpterygoid Approaches

Introduction  The endoscopic endonasal transpterygoid approach (EETPA) with or without the addition of the endoscopic-assisted sublabial anterior transmaxillary approach (ESTA) has become increasingly utilized for lesions posterior to the pterygopalatine fossa (PPF), including infratemporal fossa (ITF), lateral recess of the sphenoid sinus, Meckel's cave, petrous apex, and parapharyngeal space. The main goal of this study is to develop an educational resource to learn the steps of the EETPA for trainees. Methods  EETPA and ESTA were performed in 12 specimens by neurosurgery trainees, under supervision from the senior authors. One EETPA and one ESTA were performed on each specimen on opposite sides. Dissections were supplemented with representative cases. Results  After a wide unilateral sphenoidotomy, ethmoidectomy, and partial medial maxillectomy, the anteromedial bone limits of the PPF were identified and drilled out. The pterygoid progress was modularly removed. By enlarging the opening of the posterior and lateral walls of the maxillary sinus through EETPA and ESTA, respectively, the neurovascular and muscular compartments of the PPF and ITF were better identified. The EETPA opens direct corridors to the PPF, medial ITF, middle cranial fossa, cavernous sinus, Meckel's cave, petrous apex, and internal carotid artery. If a more lateral exposure of the ITF is needed, the ESTA is an appropriate addition. Conclusion  Despite the steep learning curve of the EETPA, granular knowledge of its surgical anatomy and basic surgical steps are vital for those advancing their learning in complex endoscopic approaches to the ventral skull base when expanding the approach laterally in the coronal plane.

How I do it? Endoscopic endonasal transpterygoid repair of sphenoid lateral recess cerebrospinal fluid leak after previous unsuccessful transcranial surgery

BACKGROUND

Direct access to the sphenoid lateral recess offers the best chance of sealing spontaneous cerebrospinal fluid (CSF) rhinorrhea caused by lateral sphenoid encephaloceles of the Sternberg canal defect.

METHOD

We present a case of spontaneous left-sided sphenoid lateral recess CSF leak after previous unsuccessful transcranial surgery managed with an endoscopic endonasal transpterygoid approach (EETA). An anatomical-based step-by-step illustration of the EETA was presented in the surgical video.

CONCLUSION

This case demonstrates the value of endoscopic endonasal transpterygoid corridor in the exposure and manipulation of the sphenoid lateral recess.

Analysis Of The Anatomical Variations Of The Sphenoid Sinus In Patients With Chronic Rhinosinusitis

Introduction - To study the anatomical variations of sphenoid sinus and its related structures and to know the association of extension of pneumatisation of sphenoid sinus with sphenoid sinusitis. Materials And Methods - This was a prospective study. Analysis of 100 patients CT PNS scans who was attending Otolaryngology clinic OPD with signs/symptoms of chronic sinusitis evaluated between September 2019 to April 2021. The pneumatization of adjacent structures of sphenoid sinuses and its relation with the protrusion of neurovascular structures surrounding the sinus and the association between the extension of pneumatisation of sphenoid sinus and presence of sphenoid sinusitis have been investigated. Chi-square test was used for statistical analysis. The p value < 0.05 was expressed as significant. Result - The association of extension of pneumatisation of sphenoid sinus with sphenoid sinusitis was statistically significant (p < 0.001) i.e. sphenoid sinusitis is seen more in patients having absence of extension of peumatization of sphenoid sinus. We also observed that seller type of pnematization (89%) is most common type. Type 1 variation (76%) is most common for Optic nerve variations, Type 3 is most common type (83%) for variation of Foramen rotendum, and Vidian canal (85%) passing through the sphenoid sinus. Conclusion - In conclusion we observed that seller type of pnematization is most common type. Type 1 variation is most common for Optic nerve variations, Type 3 is most common type for variation of Foramen rotendum, and Vidian canal passing through the sphenoid sinus, we also concluded that sphenoid sinusitis is more common in sphenoid sinus with absence of extension of pneumatisation.

Isolated Sphenoid Sinus Disease in Children

The rarity of isolated sphenoid sinus disease (ISSD) and the specificity of pediatric populations meant that a separate analysis was required in this study. This study aimed to present and discuss the results of an analysis of clinical manifestations, radiological findings and surgical methods based on a large series of exclusively pediatric patients. The study group covered 28 surgically treated children (aged 5.5-17.5 years). The medical data were retrospectively analyzed and meticulously discussed with regards to presenting signs and symptoms, radiographic findings, surgical approaches, complications, post-op care, histopathological results and follow-ups. The dominant symptom was a persistent headache (78%). Four children presented visual symptoms, diplopia in two cases, visual acuity disturbances in one case and both of these symptoms in one patient. Sixteen children presented chronic isolated rhinosinusitis without nasal polyps, six suffered from mucocele and one presented chronic sphenoiditis with sphenochoanal polyp. Four patients turned out to exhibit neoplastic lesions and developmental bony abnormality was diagnosed in one case. No fungal etiology was revealed. The transnasal approach was used in 86% of patients. A transseptal approach with concurrent septoplasty was used in four patients. The patient with visual acuity disturbances completely recovered after the surgery. All children with visual symptoms reported improvement in the vision immediately after surgery. No postoperative complications were observed. Fungal etiology was extremely rare in the pediatric population with ISSD. The surgical treatment should be a minimally invasive procedure regarding a limited range of the pathology in ISSD. Emergency surgery should be performed if ISSD produces any visual loss.

[Endonasal repair of spontaneous CSF fistulas of the lateral recess of the sphenoid sinus]

CSF fistulas of the lateral recess of the sphenoid sinus are a rare surgical pathology. Cerebrospinal fluid leak from lateral recess of the sphenoid sinus is observed with a frequency of 7.7% among all leakafe of the skull base. The article presents 3 clinical cases of patients with spontaneous cerebrospinal fluid leak from lateral recess of the sphenoid sinus and surgical treatments by transsphenoidal and transpterygoid (transpterygoid) endoscopic approaches with various postoperative results. The plastic surgery success of CSF fistulas from lateral recess of the sphenoid sinus doesn`t depend on the type of endonasal surgical approach, but on the plastic quality and the preoperative level of CSF pressure.

Endonasal Exposure of Lateral Recess of the Sphenoid Sinus: Significance of Pterygoid Process Pneumatization

Background

Caudal pneumatization of the pterygoid process may impact endonasal exposure of the lateral recess of sphenoid sinus (LRSS).

Objectives

This study aims to explore the implications of a pneumatized pterygoid process for an endonasal transpterygoid approach to the LRSS and to define strategies regarding the preservation or sacrifice of the vidian nerve.

Methods

Dissection of the LRSS (11 sides) was performed on 6 cadaveric specimens, preselected for the radiographic presence of an LRSS. In addition, the dimensions of the LRSS were measured on the deidentified CT images of 120 patients (240 sides). The sphenoid sinus was subdivided into 3 categories: Type 1 (no identifiable LRSS), Type 2 (lateral pneumatization of the greater wing above the vidian canal), and Type 3 (pneumatization of both the greater wing and the pterygoid process).

Results

On the cadaveric specimens, a Type 2 pneumatization often allowed access to the LRSS above the level of the vidian canal; thus, sparing the vidian neurovascular bundle. In Type 3 pneumatization, a frontal corridor through the pterygoid base could be created to reach the LRSS with preservation of the vidian nerve. Extreme Type 3 pneumatization, however, required the transposition or sacrifice of the vidian nerve to facilitate a full direct access to the superolateral LRSS. Measurements on CT images revealed that the extent of caudal pneumatization of the pterygoid process had no statistically significant correlation with the superolateral extension of the lateral recess in patients with Type 3 LRSS ( P > .05).

Conclusion

Pneumatization of the LRSS toward a caudal or superolateral direction may develop independent from each other. Caudal pneumatization of the pterygoid process seems to variably impact the endonasal exposure of the LRSS.

Comparison of two surgical approaches in the management of cerebrospinal fluid rhinorrhea in the lateral recess of sphenoid sinus: A retrospective study

BACKGROUND

Cerebrospinal fluid (CSF) leakage from the lateral recess of the sphenoid sinus (LRSS) is usually repaired using endoscopic endonasal approaches, which can be challenging. Various surgical techniques have been developed for the disease.

OBJECTIVE

To report our experience with repairing CSF leak from the LRSS via transethmoid sphenoidotomy approach (TESA) and transprelacrimal recess pterygoid root approach (TPLRA), to assess the efficiency of TPLRA by comparing it with TESA.

METHODS

This retrospective study included patients with LRSS CSF rhinorrhea who underwent TESA (n = 10) or TPLRA (n = 5) from January 2011 to December 2020. Demographic characteristics and operation-related parameters were recorded.

RESULTS

The mean operation time was 169.5 and 225.0 mins in the TESA and TPLRA groups, respectively, with a mean blood loss of 65 mL and 68 mL, respectively. Histopathological examinations confirmed encephalocele in 11 (73.33%) and 4 (26.67%) cases with meningocele, respectively. CSF rhinorrhea was successfully repaired in the first attempt in both groups during the mean follow-up time of 54 months. Postoperative permanent numbness of the cheek was observed in two patients in the TESA group. No cases of lacrimal overflow or subjective dry eye were observed.

CONCLUSIONS

The TPLRA, which could be an alternative procedure to treat CSF rhinorrhea in the LRSS, provides a straight-line trajectory and effective maneuverability. We also found that CSF rhinorrhea in the LRSS was accompanied by encephalocele or meningocele, with encephalocele presenting more commonly.

Infra-Temporal and Pterygo-Palatine Fossae Tumors: A Frontier in Endoscopic Endonasal Surgery—Description of the Surgical Anatomy of the Approach and Report of Illustrative Cases

Infratemporal and pterygopalatine fossae (ITF and PPF) represent two complex paramedian skull base areas, which can be defined as jewelry boxes, containing a large number of neurovascular and osteomuscular structures of primary importance. They are in close communication with many craniofacial areas, such as nasal/paranasal sinuses, orbit, middle cranial fossa, and oral cavities. Therefore, they can be involved by tumoral, infective or inflammatory lesions spreading from these spaces. Moreover, they can be the primary site of the development of some primitive tumors. For the deep-seated location of ITF and PPF lesions and their close relationship with the surrounding functional neuro-vascular structures, their surgery represents a challenge. In the last decades, the introduction of the endoscope in skull base surgery has favored the development of an innovative anterior endonasal approach for ITF and PPF tumors: the transmaxillary-pterygoid, which gives a direct and straightforward route for these areas. It has demonstrated that it is effective and safe for the treatment of a large number of benign and malignant neoplasms, located in these fossae, avoiding extensive bone drilling, soft tissue demolition, possibly unaesthetic scars, and reducing the risk of neurological deficits. However, some limits, especially for vascular tumors or lesions with lateral extension, are still present. Based on the experience of our multidisciplinary team, we present our operative technique, surgical indications, and pre- and post-operative management protocol for patients with ITF and PPF tumors.

Endoscopic Repair of Spontaneous Cerebrospinal Fluid Leaks in the Lateral Recess of the Sphenoid Sinus

OBJECTIVE

This study aimed to assess the effectiveness of 3 endoscopic endonasal approaches for the management of cerebrospinal fluid (CSF) leaks and meningoencephaloceles in the lateral recess of the sphenoid sinus (LRSS).

STUDY DESIGN

Retrospective study.

SETTING

University hospital.

METHODS

This study retrospectively reviewed 49 patients with CSF leaks and meningoencephaloceles in the LRSS. Three endoscopic surgical repair approaches were indicated based on 5 different Rhoton's types of the LRSS. The postoperative symptoms, complications, and follow-up outcomes were investigated and evaluated.

RESULTS

The success rate of endoscopic surgical repair was 100% at a median follow-up of 75.06 (12-203.4) months. Endoscopic approaches to the LRSS included the prelacrimal recess (PLR) (18.37%), transsphenoidal (18.37%), and transpterygoid approaches (64.26%). All patients in the PLR approach (PLRA) group and most of the patients in the transpterygoid approach group had a full lateral type LRSS. Hypoesthesia and dry eyes were reported in 5 patients (55.56%) and 1 (11.12%) patient, respectively, from the PLRA group and in 6 (19.35%) and 5 (16.12%) patients, respectively, from the transpterygoid approach group.

CONCLUSIONS

Endoscopic closure is a safe and effective method for the treatment of CSF leaks and meningoencephaloceles in the LRSS. The transpterygoid approach and PLRA offer adequate exposure of the LRSS with extensive lateral pneumatization or a full LRSS. The endoscopic route of the PLRA is more direct than that of the transpterygoid approach. Careful preoperative imaging evaluation is crucial while selecting the optimal surgical approach for the repair of a skull base defect.

[Endoscopic endonasal reconstruction of skull base defects in the lateral recess of the sphenoid sinus: evaluation of computed tomograms for planning operations]

OBJECTIVE

Determine the influence of the anatomical features and sizes of the lateral pocket with a defect on the choice of surgical access and the quality of the performed plastics.

MATERIAL AND METHODS

A retrospective analysis of computed tomograms of 38 patients who underwent surgical treatment at the Burdenko National Medical Research Center for Neurosurgery of the Ministry of Health of Russia about defects of the skull base in the area of the lateral pocket of the sphenoid sinus. The patients were divided into three groups depending on the approach used (the 1st group), the recurrence rate (the 2nd group), and the characteristics of intraoperative visualization of the defect (the 3rd group).

RESULTS

There were no statistically significant differences in anatomical features in patients who underwent trans-pterygoid and transsphenoidal approaches, as well as in patients of the 2nd group. Patients of the 3rd group (with visualization features) showed statistically significant differences between the distance from the defect to the VR line (p=0.007). In patients with good visualization of the defect using direct optics, this distance was shorter than in patients in whom the defect was visualized with an angled endoscope. No other anatomical differences were noted.

CONCLUSIONS

The anatomical features of the lateral pocket structure (type of pneumatization, size and volume) did not affect the choice of access to the defect and the frequency of recurrence. When comparing the approaches, it was noted that the trans-pterygoid access, providing direct visualization of defects, minimizes the risk of recurrence in the postoperative period. An objective anatomical indicator for choosing an access to the defects of the lateral pocket can be the distance from the defect to the VR line: at a distance of more than 0.7 cm, it is advisable to perform a trans-pterygoid approach; at a distance of less than 0.7 cm, it is possible to achieve direct visualization of the defect and perform high-quality plastic surgery with a transsphenoidal access.

Trigeminal Numbness After Intracranial Repair of a Spontaneous Meningoencephalocele of the Lateral Wall of the Sphenoid Sinus

A 58-year-old female with an eight-year history of rhinorrhea and a two-day history of subjective fever, chills, and vomiting presented to the emergency department for neurosurgical evaluation. Brain MRI demonstrated herniation of the meninges and portions of the inferomedial right temporal lobe through a defect of the lateral wall of the right sphenoid sinus, extending to the sphenoethmoidal recess and posterior right ethmoid air cells. A right pterional craniotomy was performed where the herniated part of the right temporal lobe, and its associated meninges, were excised. After surgery, she had hypoesthesia at the right maxillary division of the trigeminal nerve. This finding was caused by the proximity of the trigeminal nerve to the dural dissection that we performed at the bone defect. This rare complication has never been described after intracranial surgery. Only eight literature reports have described hypoesthesia or paresthesia of the trigeminal nerve after endoscopic resection of a sphenoid sinus meningoencephalocele. The patient has not had any recurrence of rhinorrhea after a six-month follow-up period.

Transcranial extradural subtemporal repair for sphenoid sinus lateral recess meningoencephalocele: technical note

Cranial meningoencephalocele is a rare condition consisting of the herniation of meninges, CSF, and brain tissue through a cranial or skull base defect. Sphenoid sinus lateral recess meningoencephalocele is of particular interest due to the complex anatomy surrounding the bone defect and their demanding surgical management. In this technical note, we reported a step-by-step description of a rare case of sphenoid sinus lateral recess meningoencephalocele causing headache due to recurrent cerebrospinal fluid leak treated with a subtemporal craniotomy with extradural middle cranial fossa drilling and meningoencephalocele removal with multilayer reconstruction. The transcranial route is a safe and effective treatment for sphenoid sinus lateral recess meningoencephalocele repair. The subtemporal extradural approach allows for an optimal exposure of the relevant anatomy minimizing risks and improving the possibility to perform an effective multilayer skull base reconstruction.

Modified Transpterygoid Approach to Sphenoid Meningoencephaloceles: A Shorter Run for a Longer Slide

OBJECTIVES

Cerebrospinal fluid (CSF) leaks and meningoencephaloceles originating in the lateral recess of the sphenoid sinus can be challenging. The traditional transpterygoid approach through the pterygopalatine fossa (PPF) is time consuming and places important structures at risk, which can lead to significant morbidity. We report a multi-institutional experience using a simplified, endoscopic modified transpterygoid approach (MTPA), which spares the PPF contents in the management of lateral sphenoid sinus meningoencephaloceles and CSF leaks.

STUDY DESIGN

Multi-Institutional, Retrospective Case Series.

METHODS

Patients with lateral sphenoid recess CSF leaks and meningoencephaloceles between 2014 and 2020 who underwent the MTPA at two academic medical centers were identified. Repair techniques and outcomes were evaluated.

RESULTS

Thirty-three patients underwent the MTPA for management. Skull base reconstruction was performed using a free mucosal graft (24/33, 72.7%), nasoseptal flap (4/33, 12.1%), bone grafts (3/33, 9.1%), and abdominal fat grafts (2/33, 6.1%). Lumbar drains and perioperative intracranial pressure measurements were routinely employed. Postoperative complications were uncommon and included three patients (9.7%) with temporary V2 anesthesia, one patient (3.2%) with prolonged V2 anesthesia, and one patient (3.2%) with subjective dry eye, all of which resolved at 9 months postoperatively. There were no recurrent CSF leaks resulting in a 100% success rate. Average follow-up was 13 months.

CONCLUSION

The MTPA reduces morbidity and greatly simplifies access to the lateral sphenoid sinus for the management of CSF leaks and meningoencephaloceles, without compromising exposure. This technique avoids the need for extensive PPF dissection and should be considered for the management of benign lesions involving the lateral sphenoid sinus.

LEVEL OF EVIDENCE

IV Laryngoscope, 2021.

Synchronous pleomorphic adenoma in the infratemporal fossa and contralateral submandibular gland and endoscopic removal

The objective of this article is to elucidate on our experience with the first case reported in the literature of a synchronous presentation of pleomorphic adenoma (PA) in infratemporal fossa as well as the contralateral submandibular gland. PA most commonly arises from the major salivary glands but has also been reported to arise from minor salivary glands in unusual sites such as the nasal septum, main stem bronchus, trachea, lacrimal gland, external auditory canal, etc. However, it seldom involves the infratemporal fossa and extremely few cases are reported in the literature and coexistent contralateral synchronous PA is nowhere reported in literature. The infratemporal fossa tumour posed a diagnostic dilemma and therapeutic challenge because of its concealed location which we dealt successfully with endoscopic sublabial trans maxillary approach.

The “Scrubbing Brush Technique” for Access to Tight Lateral Recess of the Sphenoid Sinus: A Single Case Report

Access to the lateral recess has always been a difficult task, especially in cases where the entrance to the lateral recess is very narrow. Various strategies have been described to approach it. Our study proposes a unique method of clearing debris in patients with concretions within the lateral recess. The “scrubbing brush technique” is based on easily accessible tools and has the exceptional advantage of being user friendly and having minimal potential side effects.

Simplifying Access to the Lateral Sphenoid Recess: A Modification of the Transpterygoid Approach

BACKGROUND

Meningoencephaloceles originating in the lateral recess of the sphenoid sinus can be difficult to access. Historically, the endoscopic transpterygoid approach was advocated, which carries additional morbidity given the dissection of the pterygopalatine fossa (PPF) contents to provide a direct line approach to the defect. Given our increased facility with angled endoscopes and instrumentation, we now approach this region in a less invasive manner.

METHODS

We describe the endoscopic modified transpterygoid approach (MTPA), a quicker approach to the lateral sphenoid recess which preserves the PPF contents through a single nostril corridor.

RESULTS

In the MTPA, the face of the sphenoid and anterior junction of the pterygoid plates are removed, allowing for mobilization of the PPF contents with the periosteum intact. Angled instrumentation is then used to resect the meningoencephalocele and repair the skull base defect in the lateral recess. If increased exposure is needed, this can be gained by sacrificing the sphenopalatine artery and even the vidian nerve, although this is rarely required.

CONCLUSIONS

The MTPA obviates the need for PPF dissection and simplifies access to the lateral sphenoid recess while minimizing postoperative morbidity. This approach should be considered for accessing meningoencephaloceles and other benign lesions in this challenging location.

Plasma Ablation-Assisted Endoscopic Endonasal Transpterygoid Approach to Sphenoid Lateral Recess Cerebrospinal Fluid Leaks: Technique and Outcome

BACKGROUND

Management of sphenoid lateral recess (SLR) cerebrospinal fluid (CSF) leaks present a challenge because of the location and requiring complete visualization of the defect for a successful repair. The endoscopic endonasal transpterygoid approach (EETPA) is considered the gold standard in addressing these defects. We lay out our experience in implementing this approach with plasma ablation.

METHODS

This is a case series of 11 diagnosed patients of SLR CSF leaks who underwent plasma ablation-assisted EETPA repair by a single surgeon between 2011 and 2020 at our institution. Outcomes in terms of surgical field grade on the Wormald 11-point grading scale, postoperative complications, healing on nasal endoscopy and imaging, and surgical success rate were assessed.

RESULTS

The etiology was spontaneous leak in 10 (90.9%) patients and secondary to temporal lobe abscess and/or meningitis in one (9.09%). Three (27%) patients were previously operated elsewhere by the transsphenoidal route, which we reoperated by this technique. As per Wormald grading, grade 1 field in 3 (27.27%), grade 2 in 6 (54.5%), and grade 3 in 2 cases (18.18%) were noted. Complications occurred in 3 patients (27%) in the form of dry eye (9%), meningitis (9%), and transient CSF rhinorrhea in the immediate postoperative period (9%). Repair sites were well healed on follow-up nasal endoscopy and imaging. The surgical success rate was 100%.

CONCLUSIONS

Plasma ablation-assisted EETPA allows for a uninostril approach to the SLR, easy accessibility, and better visualization with a bloodless field, which allows appropriate repair, thus minimizing complications and preventing recurrence.

Lateral Transorbital Versus Endonasal Transpterygoid Approach to the Lateral Recess of the Sphenoid Sinus-A Comparative Anatomic Study

BACKGROUND

The treatment of cerebrospinal fluid leaks of the lateral recess of the sphenoid sinus (LRSS) faces difficulties due to the deep location of the osseous defect. When treated with craniotomies, brain retraction is a concern. The endoscopic endonasal transpterygoid approach (EETA) is a direct and less invasive procedure; however, it may require transection of the vidian nerve (VN).

OBJECTIVE

To investigate the feasibility of a lateral transorbital approach (LTOA) as an alternative pathway to the LRSS that avoids VN sacrifice.

METHODS

Six embalmed heads with well-pneumatized LRSS were preselected by inspecting their computed tomography scans. One LTOA and one EETA were performed on 1 side of each specimen. The approaches were compared regarding working distance and neurovascular structures being sacrificed. The working area of the LTOA was also measured.

RESULTS

The average working distances were 59.9 (±2.94) mm for the LTOA and 76.4 (±3.99) mm for the EETA (P < .001). The LTOA generated a working area with a diameter of 9 to 14 mm. The EETA demanded the sacrifice of VN and the sphenopalatine artery in all specimens to expose the LRSS. No neurovascular structures were found in the trajectory of the LTOA.

CONCLUSION

The LTOA to the LRSS is feasible, with minimal risk of injuring neurovascular structures. It offers a shorter pathway when compared to the EETA. Although the LTOA provides no options for vascularized flap reconstruction, it allows immediate access to muscle grafts. The LTOA may serve as an alternative to treating cerebrospinal fluid leaks of the LRSS.

Management of Cerebrospinal Fluid Rhinorrhea in the Sphenoid Sinus Lateral Recess Through an Endoscopic Endonasal Transpterygoid Approach With Obliteration of the Lateral Recess

BACKGROUND

Cerebrospinal fluid rhinorrhea in the sphenoid sinus lateral recess is a rare occurrence and poses unique challenges due to limited surgical access for surgical repair.

OBJECTIVE

To report our experience of surgical repair of cerebrospinal fluid rhinorrhea in the sphenoid sinus lateral recess through an endoscopic endonasal transpterygoid approach with obliteration of the lateral recess. To evaluate the efficiency of this surgical procedure.

METHODS

A retrospective study. Twelve cases with cerebrospinal fluid rhinorrhea in the sphenoid sinus lateral recess were reviewed. Assisted by image-guided navigation, cerebrospinal fluid rhinorrhea was repaired through an endoscopic endonasal transpterygoid approach, with obliteration of the lateral recess. Complications and recurrence were recorded. Medical photographs were used.

RESULTS

This surgical approach provided a relatively spacious corridor to dissect the sphenoid sinus lateral recess and do postoperative surveillance. The repair area completely healed in 3 months after surgery. Cerebrospinal fluid rhinorrhea in the sphenoid sinus lateral recess was successfully repaired on the first attempt in all cases (100%). No main complications or recurrence was observed during a mean follow-up time of 40.3 months.

CONCLUSION

The endoscopic endonasal transpterygoid approach gives appropriate access for the treatment of spontaneous cerebrospinal fluid rhinorrhea in the sphenoid sinus lateral recess. Multilayer reconstruction of a skull base defect with obliteration of the lateral recess is a reliable and simple method.

Minimally Invasive Lateral Paraorbital Approach for Repairing Lateral Recess of the Sphenoid Sinus Spinal Fluid Leak

BACKGROUND

Cerebrospinal fluid (CSF) leaks in the lateral recess of the sphenoid sinus (LRSS) are typically spontaneous in nature and require surgical repair. Endoscopic endonasal approaches have become the mainstay of CSF leak repair in the LRSS, though they remain technically challenging and place the vidian nerve (VN) and sphenopalatine artery (SPA) at risk. Here we present a lateral paraorbital approach (LPOA) as a minimally invasive transcranial VN and SPA sparing alternative for LRSS CSF leak repairs.

CASE DESCRIPTION

A 41-year-old African American woman presented with headaches and was found to have a spontaneous CSF leak in the LRSS. A LPOA was used to repair the CSF leak. An incision was made along the frontal process of zygoma (FPZ). Removal of the overhanging portion of the FPZ while sparing the lateral orbital rim and retraction of the temporalis muscle allowed for a tangential approach to the LRSS. A small encephalocele was seen and resected; the defect was identified and repaired with onlay DuraGen (Integra LifeSciences, Princeton, NJ) and Dura Repair (J&J Medical Devices, New Brunswick, NJ). There were no postoperative complications or recurrence of CSF leak.

CONCLUSIONS

The LPOA can be a useful alternative approach to the LRSS for CSF leak repair. The lateral-to-medial approach to defects in this area provides a shorter working distance while avoiding critical neurovascular structures.

Modified Ipsilateral Endonasal Endoscopic Trans-Sphenoidal Approach to Sphenoid Sinus Lateral Recess Cerebrospinal Fluid Leak Management in Two Cases: A Technical Note

Background  Cerebrospinal fluid (CSF) leak from the sphenoid sinus lateral recess (SSLR) is very rare. Majority prefer transpterygoid approach which is extensive and time consuming. Two such cases were managed with least possible dissection/destruction of paranasal sinus. Methods  Two cases of SSLR were accessed through the ipsilateral nostril from the side of CSF leak. Wide ipsilateral anterior sphenoidotomy was done preserving intersinus septum of sphenoid sinus. Middle turbinate was lateralized and remaining paranasal structures were preserved. Two handed single nostril approach was done in both the cases by 45- and 70-degree endoscope along with angled instruments. SSLR defects were visualized and packed with autologous fat graft and glue. Results  SSLR defects could be visualized and packed with fat graft in both the cases from ipsilateral side. Both cases had uneventful outcome with no leak with mean -follow-up of 11.5 months. Conclusion  Modified ipsilateral endonasal endoscopy trans-sphenoidal approach is least invasive technique for SSLR leak. Use of angled scope and instruments help in defect visualization, avoiding extensive paranasal sinus dissection and bony removal. Tedious time-consuming reconstructive procedures can be avoided with simple fat graft with good outcome.

Endoscopic management of lateral sphenoid cerebrospinal fluid leaks: Identifying a radiographic parameter for surgical planning

OBJECTIVE

Repair of cerebrospinal fluid (CSF) leaks of the lateral recess of the sphenoid (LRS) sinus can be challenging to accomplish via an endoscopic transphenoidal approach. The endoscopic transpterygoid approach can improve surgical access to the lateral recess but requires more extensive surgical dissection. We review our experience with LRS CSF leak repair via both techniques to determine whether preoperative radiologic data can help predict the most appropriate surgical approach.

METHODS

Electronic medical records of patients with LRS CSF leaks were retrospectively reviewed at a single tertiary referral center. Radiographic measurements from preoperative computed tomography images were reviewed.

RESULTS

Twenty-two LRS CSF leaks were identified. The transphenoidal and transpterygoid approach were used in 6 (27.3%) and 16 (72.7%) cases, respectively.The mean vidian canal to foramen rotundum angle of the repairs accessed transphenoidally as compared to the transptyergoid approach were not significantly different (41.93° ±10.91, 40.72° ±19.49, respectively; P = .63). However, the mean volume of the LRS accessed by the transpterygoid approach was significantly greater compared to those accessed through the transphenoidal approach (0.97 cm3 ± 0.48, 0.39 cm3 ± 0.40, respectively; P = .04). A LRS volume of 0.400 cm3 or greater predicted the use of the transpterygoid approach with 93.3% sensitivity and 60.0% specificity.

CONCLUSION

This study demonstrated that LRS CSF leaks that necessitated repair by the transpterygoid approach, rather than transphenoidal approach, were in the context of significantly larger lateral recess. Assessment of the LRS volume is a quantifiable parameter to aid in preoperative surgical planning.

LEVEL OF EVIDENCE

Level 4.

Endoscopic prelacrimal approach to lateral recess of sphenoid sinus: feasibility study

BACKGROUND

Various pathologies, including cerebrospinal fluid leaks and meningoencephaloceles, may arise in the lateral recess of the sphenoid sinus (LRSS), which may be accessed via an endonasal transpterygoid approach. The objective of this study was to evaluate the feasibility of accessing the LRSS via an endoscopic prelacrimal approach. Furthermore, we hypothesized that this approach may protect the pterygopalatine ganglion and vidian nerve.

METHODS

Five cadaveric heads (9 sides) with a well-pneumatized LRSS were identified and an endonasal prelacrimal approach was performed. The infraorbital nerve, at the orbital floor, served as a critical landmark. After identification of the foramen rotundum at the pterygoid base, the vascular compartment of the pterygopalatine fossa and the pterygopalatine ganglion were displaced inferomedially and superomedially, respectively. Drilling of the bone inferomedial to the foramen rotundum allowed entry into the LRSS.

RESULTS

The average distances from the prelacrimal window to the pterygoid base and the posterior wall of the LRSS were 6.22 ± 0.39 cm and 7.16 ± 0.50 cm, respectively. The average areas of the bony prelacrimal window and pterygoid base window were 4.33 ± 0.32 cm² and 0.73 ± 0.10 cm² , respectively. The LRSS could be accessed using a 0-degree endoscope, and pterygopalatine neurovascular structures, including the pterygopalatine ganglion and vidian nerve, could be preserved on all 9 sides.

CONCLUSION

Our findings suggest that an endonasal prelacrimal approach provides a reasonable alternative to access the LRSS while preserving the vidian nerve and pterygopalatine ganglion.

Cranial nerve V2 and Vidian nerve trauma secondary to lateral pterygoid recess encephalocele repair

BACKGROUND

The incidence of adverse sequelae related to trauma of cranial nerve V₂ (V2) and the Vidian nerve (VN) during endoscopic pterygoid recess repair (PRR) of lateral sphenoid encephalocele is insufficiently reported in the medical literature. As part of our quality assessment and improvement program we sought to analyze the incidence and severity of V2 and VN injury during a 9-year experience (2010-2018) with PRR.

METHODS

Hypoesthesia, paresthesia, and dry eye and their impact on patient quality of life were sought through chart review and a self-reported 0 to 5 Likert scale for each symptom.

RESULTS

Thirty-five patients underwent repair of spontaneous cerebrospinal-fluid (CSF) rhinorrhea, with 11 consecutive patients undergoing endoscopic PRR. Mean follow-up for PRR was 32.5 months (range, 2.4 to 103.3 months). Although definitive management resulted in 100% success, 1 required secondary treatment. Eight patients were available for long-term follow-up (72.7%) and completed a symptom severity questionnaire using a Likert-scale. All patients observed either hypoesthesia, paresthesia, or dry eye of varying gradation (scale, 0 to 5). None described disabling symptoms, and some reported gradual improvement. Numbness, paresthesia, and dry eye were reported by 6 of 8 (75%), 5 of 8 (62.5%), and 4 of 8 (50%) patients, respectively. The mean Likert score among the 8 patients who completed this questionnaire noticing hypoesthesia, paresthesia, and dry eye was 2.6, 1.3, and 1.8, respectively.

CONCLUSION

Meticulous surgical technique is paramount for successful PRR and minimizing nerve injury, yet the anatomic variation of the lateral pterygoid recess can be challenging, and neural injury is a real risk. Preoperatively, patients should be counseled that although V2 or VN injury is common, most patients describe resulting symptoms to be rarely bothersome.

Anatomo-radiological study supporting the use of ipsilateral nasoseptal flap for the transpterygoid management of temporo-sphenoidal meningoceles. A review of 21 cases

OBJECTIVES

Surgical treatment of temporo-sphenoidal meningoceles involves the reduction of the meningocele, watertight closure and defect coverage with a nasoseptal flap (NSF). It can be performed contralaterally or ipsilaterally: in the latter situation, the pedicle of the flap must be dissected into the pterygopalatine fossa. The objective of this study was to evaluate the benefit of using an ipsilateral NSF in transpterygoid approaches for the management of temporo-sphenoidal meningoceles, compared to a contralateral NSF, based on a radiological study.

MATERIAL AND METHODS

Retrospective monocentric study of 21 cases, between 2002 and 2018. Measurement of the NSF lengths, and lengths needed to cover the defect were evaluated on the preoperative scanner. Early and later failure and complication rates were evaluated.

RESULTS

Seventeen cases of temporo-sphenoidal meningoceles with available CT scan were identified. The mean duration of follow up was 27.9 months [1-147]. Theoretical lengths of the ipsi and contralateral NSF were comparable: 71.4±7.8mm vs. 78.8±8mm, P=0.729. In 8 cases/18 (42%), the theoretical length of the contralateral NSF was not long enough to cover the defect beyond the V2 (mean lack of 8.87±6.6mm). In all cases, the theoretical length of the ipsilateral NSF was sufficient to cover the defect. In the case series, failure and complication rates were similar.

CONCLUSION

The use of an ipsilateral NSF for the transpterygoid management of temporo-sphenoidal meningoceles, although more complex, allows a better coverage of the defect, compared to the contralateral NSF, which is not long enough in 42% of cases.

Transnasal transpterygoid resection of meningoencephalocoele with abolition of seizures

Meningoencephalocoeles are herniations of intracranial contents through skull base defects. Patients may present with a plethora of symptoms ranging from cerebrospinal fluid (CSF) rhinorrhoea to epileptic convulsions, or indeed may be asymptomatic. We present a case of a 24-year-old man suffering from new onset, drug-resistant tonic-clonic seizures. Imaging studies revealed neural tissue and meninges protruding through the pterygoid portion of the sphenoid bone, into the anteromedial aspect of the middle cranial fossa. An image-guided endoscopic transnasal transpterygoid approach was carried out as a joint otolaryngological and neurosurgical procedure, resulting in the patient being seizure-free for over 12 months postoperatively. There is a paucity of literature supporting such an endoscopic approach to treat epilepsy secondary to a meningoencephalocoele. We illustrate that this is a safe and minimally invasive treatment option which ultimately rendered the patient free of all anticonvulsants.

Characterization of Anatomical Landmarks for Exposing the Internal Carotid Artery in the Infratemporal Fossa Through an Endoscopic Transmasticator Approach: A Morphometric Cadaveric Study

BACKGROUND

The Eustachian tube and sphenoid spine have been previously described as landmarks for endonasal surgical identification of the most distal segment of the parapharyngeal internal carotid artery (PhICA). However, the intervening space between the sphenoid spine and PhICA allows for error during exposure of the artery. In the present study, we have characterized endoscopic endonasal transmasticator exposure of the PhICA using the sphenoid spine, vaginal process of the tympanic bone, and the "tympanic crest" as useful anatomical landmarks.

METHODS

Endonasal dissection was performed in 13 embalmed latex-injected cadaveric specimens. Two open lateral dissections and osteologic analysis of 10 dry skulls were also performed.

RESULTS

A novel and palpable bony landmark, the inferomedial edge of the tympanic bone, referred to as the tympanic crest, was identified, leading from the sphenoid spine to the lateral carotid canal. Additionally, the vaginal process of the tympanic bone, viewed endoscopically, was a guide to the PhICA. The sphenoid spine was bifurcate in 20% of the skulls, with an average length of 5.98 mm (range, 3.9-8.2 mm), width of 5.81 mm (range, 3.0-10.6 mm), and distance to the carotid canal of 4.48 mm (range, 2.5-6.1 mm).

CONCLUSION

The sphenoid spine and pericarotid space has variable anatomy. Using an endoscopic transmasticator approach to the infratemporal fossa, we found that the closest landmarks leading to the PhICA were the tympanic crest, sphenoid spine, and vaginal process of the tympanic bone.

Endoscopic Endonasal Transpterygoid Approach to Sphenoid Sinus Lateral Recess Defects

Background  Lesions affecting sphenoid sinus lateral recess (SSLR) are difficult to visualize and manipulate through the transnasal routes, especially when the sinus is highly pneumatized. External approaches to this area involve extensive surgery and are associated with significant morbidity. The aims of this study are to present our experience with the endoscopic transpterygoid approach as a method for approaching lesions of the SSLR and to evaluate the outcomes of this procedure. Methods  Clinical charts of patients who had lesions in the SSLR and who were treated at our institution from September 1998 to June 2018 were retrospectively reviewed. All these patients were managed by the endoscopic endonasal transpterygoid approach. Results  Thirty-nine patients were identified. No cerebrospinal fluid leak recurrences were observed during follow-up (range: 1-19.7 years; median: 2.3 years). Hypoesthesia (temporary, 1; persistent, 4) in the region innervated by the maxillary branch of the trigeminal nerve was detected in five (12.8%) patients, while symptoms due to the Vidian nerve damage (dry eye, 3; dry nasal mucosa, 1) were present in four (10%) patients. Conclusions  Although the endoscopic endonasal transpterygoid approach is an excellent corridor for dealing with lesions of the SSLR, limited rate of neurologic and lacrimal complications was observed. Potential morbidity of the intervention should be discussed during preoperative counselling.

[Experience of treating patients with lateral sphenoid sinus recess CSF leak]

According to various authors, the rate of sphenoid sinus defects ranges from 15 to 26%. In the sphenoid sinus, the most common defect localization is the lateral recess - 35.3%. Regardless of the etiology and pathogenesis of lateral sphenoid sinus recess cerebrospinal fluid (CSF) leak, the treatment approach is aimed at plastic closure of the defect. Surgery in this area is associated with a high rate of recurrences (25%) due to a complex anatomical landscape and inapplicability of a direct approach.

PURPOSE

The study purpose was to analyze our own experience in treating patients with CSF leak and meningoencephalocele in the lateral sphenoid sinus recess and, based on the obtained results, develop an algorithm for the treatment of this pathology.

MATERIAL AND METHODS

We retrospectively reviewed a series of 89 patients with CSF leak and meningoencephalocele in the lateral sphenoid sinus recess who were treated at the Burdenko Neurosurgical Institute in the period between 2001 and 2017. The demographic characteristics of patients, clinical data, and aspects of surgical treatment were analyzed. Treatment outcomes were assessed based on analysis of recurrences and postoperative complications. The obtained data were compared to the literature data.

RESULTS

In the series of 89 patients with CSF leak and meningoencephalocele in the lateral sphenoid sinus recess, the mean age was 49 years. Surgery through the transsphenoid approach was performed in 89 (74%) patients. There were 25 (28%) recurrences in this group. Nine (7%) patients underwent repair of a complex skull base defect using the transethmoidal approach; there were 3 (33%) recurrences. The transpterygoid approach was used in 22 (17%) patients; there were 3 (14%) recurrences in this group.

CONCLUSION

Endoscopic endonasal repair is an effective technique for treating complex skull base defects in the lateral sphenoid sinus recess. The choice of an approach to the defect depends on the degree of pneumatization of the sphenoid sinus, surgeon's experience, and availability of the necessary equipment and tools. The endoscopic transpterygoid approach is advisable to use in cases of excessive pneumatisation of the sinus with developed lateral processes and recurrent nasal CSF leak. This enables visualization of the defect edges in this hard-to-reach area and adequate repair.

Management of sphenoid lateral recess encephalocoeles

PURPOSE OF REVIEW

Sphenoid sinus lateral recess encephalocoeles (SSLRE) are rare occurrences and pose unique challenges due to limited surgical access for endoscopic endonasal repair and also the lack of consensus on optimal perioperative managements specifically in the spontaneous cases, which are also believed to be a variant of idiopathic intracranial hypertension (IIH). Endoscopic endonasal approaches have largely replaced the transcranial route and the techniques are continuously being refined to reduce the neurovascular morbidity and improve outcome.

RECENT FINDINGS

Transpetrygoid is the most utilized approach with modifications suggested to limit bone removal, exposure and preservation of the neurovascular structures as dictated by the extent of the lateral recess. As more experience is gained, extended transphenoidal techniques were also successfully used for access. Lateral transorbital is a new approach to the lateral recess investigated in cadavers. IIH treatment is still controversial in the setting of SSLRE, but it appears rationale to evaluate, monitor and treat if necessary.

SUMMARY

SSLRE management should be tailored to the specific anatomical variances and cause. Modifications of techniques have been described giving different options to access the lateral recess. Successful repair for spontaneous SSLRE may require treatment of IIH if present, but the long-term outcome is still unclear.

The anatomical and radiological evaluation of the Vidian canal on cone-beam computed tomography images

INTRODUCTION

The aim of this study is to explore the anatomy of the Vidian nerve to elucidate the appropriate surgical approach based on preoperative cone-beam computed tomography (CBCT) images.

MATERIALS AND METHODS

The Vidian canal and its surrounding structures were morphometrically evaluated retrospectively in CBCT images of 400 cases by the Planmeca Romexis program. The types of the Vidian canal were determined and seven parameters were measured from the images.

RESULTS

Three types of the Vidian canal according to the relationship with the sphenoid bone were found as follows: the Vidian canal totally protruded into the sphenoid sinus (19.75%), partially protruded into sphenoid sinus (44.37%) and embedded inside bony tissue of the body of sphenoid bone (35.87%). The position of the Vidian canal was medial (34.62%), on the same line (55.12%) and lateral (10.25%) to the medial plate of the pterygoid process. The distance between the Vidian canal and the vomerine crest, the mid-sagittal plane, the round foramen, the palatovaginal canal, and the superior wall of the sphenoid sinus, the length of the Vidian canal and the angle between the Vidian canal and the sagittal plane was found to be 16.69 ± 2.14, 13.80 ± 2.00, 8.88 ± 1.60, 5.83 ± 1.37, 23.98 ± 2.68, 13.29 ± 1.71 mm and 25.78° ± 3.68° in males, 14.62 ± 1.66, 11.43 ± 1.28, 8.51 ± 1.63, 5.78 ± 0.57, 22.37 ± 2.07, 12.91 ± 1.26 mm and 23.43° ± 3.07° in females, respectively.

CONCLUSIONS

Our results may assist with proper treatment for surgical procedures around the Vidian canal with a high success rate and minimal complications. Therefore, the results obtained in this study contribute to the literature.

Endoscopic endonasal approach to the vidian nerve and its relation to the surrounding structures: an anatomic cadaver study

PURPOSE

The aim of this study was to investigate the neurovascular structures and their relevant anatomy with the endonasal endoscopic transpterygoid approach on fresh human cadavers. In addition, the relationship between the vidian nerve, ICA and surrounding structures were investigated METHODS: This study was carried out at an otolaryngology department of a tertiary medical center between June 2014 and June 2015. Ten fresh human cadavers were included in this study. Pterygopalatine fossa was explored via an endoscopic endonasal transpterygoid approach. Same surgical dissection procedures were performed on all cadavers: maxillary antrostomy, anterior and posterior ethmoidectomy, sphenoidotomy, transpterygoid pterygopalatine fossa and vidian canal dissection.

RESULTS

Mean distance between the anterior nasal spine and ethmoidal crest was 60.35 ± 1.31 mm (range 59-64 mm). Mean distance between the sphenopalatine foramen and superior border of choana was 18.30 ± 1.38 mm (range 17-22 mm). Mean distance between the vidian canal and sphenopalatine foramen was 6.30 ± 0.47 mm (range 5.5-7 mm). Mean distance between the vidian canal and anterior nasal spine was 64.6 ± 1.71 mm (range 62-67 mm). Foramen rotundum was located superior lateral to the vidian canal in all specimens. Mean distance between foramen rotundum and vidian canal was 9.45 ± 0.60 mm (range 8.5-10.5 mm). Course of the greater palatine nerve was always medial to the descending palatine artery. The mean length of the vidian nerve from the petrous ICA to the point the nerve exits the vidian canal (vidian canal length) was 17.90 ± 1.59 mm (range 16-20 mm).

CONCLUSIONS

The distances between the vidian canal and surrounding neurovascular structures would help the skull base surgeon in this narrow and complex area.

Surgical Management of Sphenoid Sinus Lateral Recess Cerebrospinal Fluid Leaks: A Single Neurosurgical Center Analysis of Endoscopic Endonasal Minimal Transpterygoid Approach

OBJECTIVE

To review the results of sphenoid sinus lateral recess (SSLR) cerebrospinal fluid (CSF) leaks treated with the endoscopic endonasal minimal transpterygoid approach (EEMTPA) and to discuss the surgical technique and outcomes.

METHODS

We performed a retrospective analysis of 13 cases who underwent SSLR CSF leak repair through the EEMTPA in our clinic between September 2008 and December 2017. Demographic and etiological features with reconstruction and surgical outcomes were examined. Mean follow-up time was 6.1 years.

RESULTS

In regard to etiology, the SSLR CSF leaks included 9 patients with spontaneous, 2 patients with traumatic, and 2 with iatrogenic causes. CSF leak was at the left lateral recess in 8 cases and at right lateral recess in 5 cases. Nine patients had empty sella syndrome, and 11 patients had meningoencephaloceles in addition to SSLR CSF leaks. All patients underwent surgery through the EEMTPA, and a multilayer closure with tissue overlay grafts were used for reconstruction. A pedicled nasoseptal flap and/or pedicled middle turbinate flap were applied to the area of the leak in all cases. One patient had a persistent CSF leak and another had recurrence, both of which required revision surgery. Our overall success rate was 100%.

CONCLUSIONS

EEMTPA is a safe and effective method that can be used to treat challenging pathologies at the SSLR, including CSF leaks accompanying meningoencephaloceles. Furthermore, the success rate of EEMTPA for SSLR CSF leaks can be increased by applying endoscopic skull base reconstruction techniques such as the pedicled nasoseptal flap and pedicled middle turbinate flap.

Epidermoids of the Paranasal Sinuses and Beyond: Endoscopic Management

Background

Epidermoid tumors of the craniofacial skeleton are uncommon, with the exception of acquired cholesteatoma of the temporal bone. These lesions may be primary embryologic in origin or, less frequently, may be iatrogenic or posttraumatic.

Methods

We report three cases of unusually encountered epidermoids, all of which were managed by endoscopic marsupialization via paranasal sinus approaches. We also review the pathophysiology and clinical presentation of these rare entities.

Results

The first patient is a 60-year-old man with a congenital epidermoid of the petrous apex removed via an endoscopic transsphenoid approach assisted by image-guided surgical navigation with CT/MRA merge. The second case is a 48-year-old woman with a history of trauma found to have a mass in the pterygopalatine space. An endoscopic transmaxillary approach was used to ligate the internal maxillary artery and marsupialize the cyst into the maxillary sinus. The third patient is a 22-year-old woman with a supraorbital ethmoid epidermoid tumor discovered intraoperatively during surgery for a presumed mucocele. This patient also had a known history of trauma. The cyst was marsupialized into the adjacent frontal sinus. Image-guided surgical navigation using CT was performed in the latter two cases. All patients are free of recurrence with follow-up ranging from 14 to 26 months.

Conclusion

With advancements in endoscopic techniques, including the use of image guidance, many of these relatively uncommon lesions can be managed by minimally invasive approaches via the paranasal sinuses.

Spontaneous CSF rhinorrhea from the trigeminal canal in an adolescent

We report a case of a seventeen-year old, healthy, non-obese young woman who presented with retro-orbital headaches and metallictasting, left-sided rhinorrhea. Computed tomography revealed a defect along the medial wall of the canal of V2 within a well-pneumatized lateral recess of the left sphenoid sinus. Prior imaging obtained 4 years earlier in the context of nasal trauma showed no such defect - thus lending support for the arachnoid granulation hypothesis of spontaneous CSF leaks from the sphenoid sinus. We perform a literature review and describe a successful repair through an endoscopic transpterygoid approach, which allowed for resolution of symptoms with minimal postoperative morbidity.

Expanded Endonasal Endoscopic Approaches to the Skull Base for the Radiologist

The cranial base is a complex 3-D region that contains critical neurovascular structures. Pathologies affecting this region represent some of the most challenging lesions to manage due to difficulty with access and risk of significant postoperative morbidity. With the development of expanded endonasal endoscopic approaches, skull base surgeons use the nose and paranasal sinuses as a corridor to access selected ventral skull base lesions. This review discusses high-resolution imaging in the evaluation of patients with skull base lesions considered for endonasal endoscopic surgery, summarizes various expanded endonasal endoscopic approaches, and provides examples of commonly used expanded endonasal endoscopic procedures.

Evaluation and treatment of isolated sphenoid sinus diseases

PURPOSE OF REVIEW

To review cause, clinical evaluation, medical and surgical management of isolated sphenoid sinus diseases.

RECENT FINDINGS

Early diagnosis of isolated sphenoid sinus diseases requires a high index of clinical suspicion and appropriate radiological imaging. Sphenoid sinus can be approached endoscopically via a few different surgical techniques.

SUMMARY

Isolated sphenoid sinus diseases are uncommon, with nonspecific clinical presentation. Early diagnosis requires a high index of clinical suspicion, proper endoscopic nasal examination, and appropriate radiological imaging. Surgical intervention is the primary treatment modality for most of the isolated sphenoid sinus diseases. Endoscopic endonasal approach to sphenoid sinus is the technique of choice. The location of sphenoid sinus disease, the extent of the surgery, and anatomic configuration of the sphenoid sinus are the main factors that help to decide the most suitable surgical approach to the sphenoid sinus.

Indications for open procedures in the endoscopic era

PURPOSE OF REVIEW

Endoscopic sinus surgery became the gold standard in inflammatory disorders of the nose and paranasal sinuses, in cerebrospinal fluid leak and epistaxis management, and established its efficacy in the oncology of the region. However, there are certain limitations which make an external approach mandatory. This article reviews the recent literature describing the cases where an open procedure is still indicated.

RECENT FINDINGS

Despite the evolution of endoscopic surgery external approaches are still indicated. Osteoplastic flap remains an option for the refractory inflammation of the frontal sinus. Benign and malignant tumours with lateral or superior extension, neurovascular involvement, and bony/soft tissue erosion usually require an external approach. Superior and lateral posterior wall defects of frontal sinus with cerebrospinal fluid leak may mandate an open procedure. Management of severe epistaxis may still necessitate in selected cases an external approach when endoscopic surgery fails and embolization setting is not available.

SUMMARY

Although advances in endoscopic instrumentation and techniques steadily decrease the indications for external approaches, they continue to have a role in the management of nasal disorders. This study summarizes the recent literature and provides a comprehensive review of the up-to-date remaining indications for open procedures in the nose and paranasal sinuses.

A modification of endoscopic endonasal approach for management of encephaloceles in sphenoid sinus lateral recess

Spontaneous cerebrospinal fluid leak with meningoencephaloceles in sphenoid sinus lateral recess is challenging. Transnasal visualization of this area is difficult, especially when large pneumatization is present. External approaches to this region involve aggressive surgery and are often associated with significant morbidity. The aim of this study is to assess the real effectiveness of a modification of the endoscopic endonasal approach for their management. This is a prospective case series study and was conducted at Otolaryngology department, Ain Shams University Hospitals, Cairo, Egypt. Seven patients with spontaneous cerebrospinal fluid leak with meningoencephaloceles in the sphenoid sinus lateral recess were included. Diagnosis was confirmed by: analysis for beta-2 transferrin and imaging. They were managed with endoscopic endonasal retrograde trans-sphenoid approach described in this study with multilayered reconstruction of the defect. Mean age of our patients was 40.14 ± 8.35 years; mean BMI was 36.37 ± 2.59 kg/m². Primary empty sella was present and osteodural defect was identified in superior wall of sphenoid sinus lateral recess with punched out and regular smooth edges. Mean intra-cranial pressure was (26.42 ± 3.87 mmH₂O) and size of defect was less than 10 mm, mean 7.85 ± 1.34. Mean-operative time was 169.28 ± 21.87 min. The mean hospital stay was 7.42 ± 1.39 days. No cerebrospinal fluid leak recurrences were observed during follow-up period that ranged from 37 to 48 months. Endoscopic endonasal retrograde trans-sphenoid approach provides a wide, safe, and direct route to the management of sphenoid sinus lateral recess cerebrospinal fluid leak.

Trauma of the midface

Fractures of the midface pose a serious medical problem as for their complexity, frequency and their socio-economic impact. Interdisciplinary approaches and up-to-date diagnostic and surgical techniques provide favorable results in the majority of cases though. Traffic accidents are the leading cause and male adults in their thirties are affected most often. Treatment algorithms for nasal bone fractures, maxillary and zygomatic fractures are widely agreed upon whereas trauma to the frontal sinus and the orbital apex are matter of current debate. Advances in endoscopic surgery and limitations of evidence based gain of knowledge are matters that are focused on in the corresponding chapter. As for the fractures of the frontal sinus a strong tendency towards minimized approaches can be seen. Obliteration and cranialization seem to decrease in numbers. Some critical remarks in terms of high dose methylprednisolone therapy for traumatic optic nerve injury seem to be appropriate. Intraoperative cone beam radiographs and preshaped titanium mesh implants for orbital reconstruction are new techniques and essential aspects in midface traumatology. Fractures of the anterior skull base with cerebrospinal fluid leaks show very promising results in endonasal endoscopic repair.

Comprehensive review on endonasal endoscopic sinus surgery

Endonasal endoscopic sinus surgery is the standard procedure for surgery of most paranasal sinus diseases. Appropriate frame conditions provided, the respective procedures are safe and successful. These prerequisites encompass appropriate technical equipment, anatomical oriented surgical technique, proper patient selection, and individually adapted extent of surgery. The range of endonasal sinus operations has dramatically increased during the last 20 years and reaches from partial uncinectomy to pansinus surgery with extended surgery of the frontal (Draf type III), maxillary (grade 3-4, medial maxillectomy, prelacrimal approach) and sphenoid sinus. In addition there are operations outside and beyond the paranasal sinuses. The development of surgical technique is still constantly evolving. This article gives a comprehensive review on the most recent state of the art in endoscopic sinus surgery according to the literature with the following aspects: principles and fundamentals, surgical techniques, indications, outcome, postoperative care, nasal packing and stents, technical equipment.

Meningocele and Meningoencephalocele of the Lateral Wall of Sphenoidal Sinus: The Role of the Endoscopic Endonasal Surgery

BACKGROUND

Meningocele and meningoencephalocele of the lateral wall of the sphenoidal sinus (LWSS) are rare lesions, crossing the borders of multiple disciplines such as ear-nose-throat, maxillofacial, and neurologic surgery. We reviewed our surgical experience to analyze the role of the endoscopic endonasal approach and consider these pathologies from different perspectives.

METHODS

All consecutive cases of meningocele and meningoencephalocele of LWSS operated through an endoscopic endonasal approach from 1998 to 2015 in our institutions were collected. Medical history, focusing on previous episodes of cerebrospinal fluid leak, meningitis or seizures, was considered. The outcome was assessed considering the medical condition and the postoperative neuroimaging.

RESULTS

The series includes 23 patients (7 male, 16 female). Mean age was 52 years (26-73 years). Eleven cases were meningoencephaloceles and 12 meningoceles. A clear cerebrospinal fluid leak occurred on in 19 patients and was associated with meningitis in 3. Two were presenting a history of epilepsy. No complications were observed, but 1 case presented seizures on waking. At follow-up (mean 84 months, 4-167) each patient is in good clinical condition with no further episodes of leaking or seizures.

CONCLUSIONS

Endoscopic endonasal surgery is a safe and effective approach for meningocele and meningoencephalocele of LWSS; it allows resection of herniated tissue and repair of the osteodural defect. The favorable clinical outcome and the possible effectiveness on seizures lead us to support this approach as first minimally invasive treatment also in presence of epilepsy, as a first low risk epilepsy surgical procedure.