Search

Objective: Identify the benefits and caveats of combining minimal access approaches to the infratemporal fossa (ITF), such as the endoscopic transnasal, endoscopic transorbital, endoscopic transoral, and endoscopic sublabial transmaxillary approaches to address extensive lesions not amenable to a single approach. The study provides anatomical metrics including area of exposure and degree of surgical freedom. Methods: Five human cadaveric specimens (10 sides) were dissected to expose and methodically analyze the anatomical intricacies of the ITF using the following minimal access approaches: endoscopic transnasal transpterygoid (EETA), endoscopic sublabial transmaxillary, endoscopic transorbital via infraorbital foramen, and endoscopic transoral techniques. Area of exposure at the pterygopalatine fossa and surgical freedom at the ITF were obtained for each approach. Results: The endoscopic sublabial transmaxillary sinus and the combined approach afford a significantly greater exposure than an isolated EETA. The difference in exposure (mean) between the endoscopic sublabial transmaxillary and EETA was 1.62 ± 0.85 cm2 (p < 0.001), and the difference between the combined approach and EETA was 4.25 ± 0.85 cm2 (p < 0.001). Conclusions: Combining minimal access endoscopic approaches to the ITF can provide significantly greater exposure than an isolated EETA; thus, providing enhanced access to address lesions with extensive involvement of the ITF, especially those with superolateral and inferolateral extensions. In addition, some approaches may have an adjunctive role to the resection, such as the endoscopic transoral approach offering the potential for early control of the internal maxillary artery and its branches, some of which may be supplying the tumor in the ITF; or the endoscopic transorbital approach yielding a direct line of sight to the superior ITF and middle cranial fossa. Level of Evidence: NA. [ABSTRACT FROM AUTHOR]

Objective: The expanded endonasal transpterygoid approach (EETA) is used to access the middle and posterior fossa through the pterygoid process. Traditionally, the eustachian tube (ET) was resected during EETA, which often required subsequent myringotomy for inner ear drainage. Anterolateral transposition of the ET was proposed to decrease potential morbidity associated with resection. However, a comparison of resection versus transposition regarding the need for subsequent myringotomy has not been reported. Methods: This is a retrospective cohort study of patients who underwent an EETA. Patient demographics, tumor characteristics, management of ET with resection versus transposition, and need for subsequent myringotomy were collected. Analysis was performed with JMP software in standard fashion and univariate and multivariate logistic regression analysis performed with a p < 0.05 was considered significant. Results: Ninety‐one patients underwent EETA for various malignant and benign tumors. Twenty‐seven patients required myringotomy, with tumors of the pterygopalatine fossa accounting for the most common location (n = 8). Malignant pathology had the highest myringotomy rate compared to benign tumors (48.9% vs. 10.9%, p < 0.001), as did receiving postoperative radiation (p < 0.001), ET resection (p < 0.001), and increasing CPK class. Multivariate analysis of these variables suggests that only ET resection significantly correlated with the need for myringotomy (LR 7.97, p = 0.005). Conclusions: ET resection during EETA can lead to ET dysfunction and require myringotomy post‐operatively, and patients should be counseled of this risk. Radiation treatment, malignant pathology, and CPK class, all reflecting situations where more extensive surgery was needed, were associated with the need for myringotomy on univariate analysis but did not reach significance with multivariate analysis. Level of Evidence: 4 Laryngoscope, 134:1203–1207, 2024 [ABSTRACT FROM AUTHOR]

Background: McCune‐Albright syndrome is a rare disorder characterized by polyostotic fibrous dysplasia (FD), café‐au‐lait skin pigmentation, and endocrine dysfunction. Extensive FD in the craniofacial region can present significant challenges in terms of disease control and carries a high risk of permanent visual impairment. Methods: We present a case of medically and surgically resistant FD that required nine optic nerve decompressions. Results: The condition was ultimately controlled with the use of the denosumab agent. Conclusion: The case highlights the importance and potential efficacy of denosumab in resistant FD management, particularly in cases involving sensitive organs. [ABSTRACT FROM AUTHOR]

Objective: To demonstrate anatomic relationships pertinent to the endoscopic multiport approach to the infratemporal fossa (ITF). Discuss advantages and limitations of each individual approach. Study Design: Cadaveric study. Methods: Endoscopic and endoscopic‐assisted endonasal transpterygoid, sublabial transmaxillary, endoscopic transorbital, and endoscopic transoral approaches to accessing the ITF were completed in five silicone‐injected fresh cadaveric specimens (10 sides) with the assistance of 0, 30, and 450 rods‐lens endoscopes. Image guidance was used to confirm and document the anatomical relationships encountered in each approach. Results: The endonasal endoscopic transpterygoid approach provides better visualization and more direct exposure to median structures. Endoscopic‐assisted sublabial transmaxillary approach enhances the field of exposure, angle of attack, and ease of instrumentation to the lateral part of the ITF. Endoscopic‐assisted transorbital approach via the inferior orbital fissure provided cephalic and anterior access. Endoscopic‐assisted transoral approach complements the access to lesions extending inferior to the hard palate or far lateral to the mandibular condyle. Conclusions: A combination of minimal access infratemporal approaches can provide adequate exposure of the entire ITF while avoiding some of the morbidity associated with open approaches. Level of Evidence: NA Laryngoscope, 133:1367–1374, 2023 [ABSTRACT FROM AUTHOR]

The styloid process constitutes the posterolateral boundary for an endonasal exposure of the infratemporal fossa. This study aims to explore the feasibility of a far‐lateral extension to the lateral poststyloid space via an endonasal corridor. An endonasal dissection was performed on six cadaveric specimens (12 sides). Following an endoscopic endonasal access to the parapharyngeal space, the styloid process and the tympanic portion of the temporal bone were removed to reveal the jugular bulb and the extratemporal facial nerve. Distances from the anterior nasal spine to the relevant landmarks were measured using a surgical navigation device. Through an endonasal corridor, only the anteroinferior aspect of the jugular bulb was exposed. Conversely, the extratemporal facial nerve could be sufficiently exposed, and the deep temporal nerve could be transposed to the stylomastoid foramen. The average horizontal distances from the nasal spine to the posterior tract of V3, styloid process, and facial nerve were 79.33 ± 3.41, 97.10 ± 4.74, and 104.77 ± 4.42 mm, respectively. Access to the lateral poststyloid space via an endonasal corridor is feasible, potentially providing an alternative approach to address select lesions extending to this region. The deep temporal nerve has a similar diameter to that of the facial nerve; thus, providing potential reinnervation of the facial nerve. [ABSTRACT FROM AUTHOR]

Background: The sphenoidal spine protrudes from the roof of the infratemporal fossa (ITF). This study aims to assess the anatomic relationships among the sphenoidal spine and other structures within the ITF from the perspective of an endoscopic endonasal access (EEA), and to explore the implications of these relationships. Methods: An EEA to the ITF was completed on six cadaveric specimens (12 sides). The anatomical relationships among the sphenoidal spine and adjacent structures were explored and associated distances from each other were measured using a navigation system. Results: The foramen spinosum is located anterosuperior to the sphenoidal spine, whereas the chorda tympani courses caudal and medial to the sphenoidal spine and the Eustachian tube and parapharyngeal internal carotid artery (pICA) are at its posterior aspect. Two virtual vertical planes, at the anterior and posterior aspects of the sphenoidal spine, respectively, correspond to the posterior trunk of V3 and middle meningeal artery, and the stylopharyngeal aponeurosis. The average length of sphenoidal spine was 8.5 ± 2.43 mm, and the distance from distal apex of the sphenoidal spine to the foramen ovale, foramen spinosum, and pICA were 10.82 ± 0.83 mm, 6.42 ± 0.52 mm, and 5.02 ± 0.54 mm, respectively. Conclusions: The sphenoidal spine is a meaningful landmark for endonasal approaches to the ITF. Measurements and conceptualization of vertical planes prior and posterior to the sphenoidal spine are beneficial to better appreciate the anatomic relationships in the ITF. [ABSTRACT FROM AUTHOR]

The pterygopalatine fossa contains a dense and complex array of neurovascular structures vulnerable to accidental surgical injury. This study aims to describe a novel landmark, the orbito‐pterygo‐sphenoidal ligament (OPSL), and implications of this structure for surgery in the pterygopalatine fossa and the inferior orbital fissure. Six cadaveric specimens (12 sides) were dissected using an endonasal approach to expose the periosteal layers associated with the pterygopalatine fossa and orbit. The thickened triangular‐shaped ligament at their confluence was termed the OPSL. Dimensions of its lateral, inferior, and medial borders were measured, and their anatomical relationships defined. The pterygopalatine ganglion and the maxillary nerve lie immediately inferior and deep into the OPSL. The superior aspect of the posterior nasoseptal artery and nerve are covered by the medial OPSL. The lateral and inferior borders of the OPSL are contiguous with the periorbita and the periosteum of the pterygopalatine fossa, respectively. Along the medial border of the ligament, the openings of the palatovaginal fissure, vidian canal, and foramen rotundum were sequentially identified in a medial to lateral trajectory. The length of the lateral, inferior, and medial borders of the triangular OPSL were 13.25 ± 0.62, 14.25 ± 0.45, and 12.08 ± 0.90 mm, respectively. The OPSL is a thick, triangular‐shaped fascial confluence, which may serve as a landmark for procedures within the pterygopalatine fossa and the inferior orbital fissure. [ABSTRACT FROM AUTHOR]

Lesions arising from the upper parapharyngeal space (UPPS) often involved the jugular foramen region (JFR), occasionally extending into the posterior cranial fossa. This study aims to investigate the surgical anatomy of the JFR and UPPS from the perspective of an expanded endoscopic approach (EEA), tracing the lower cranial nerves from their extracranial foramina to the UPPS. Six cadaveric specimens (12 sides) underwent a transpterygoid EEA to expose the JFR and UPPS. Distances from the medial pterygoid plate (MPP) to the internal carotid artery (ICA), hypoglossal canal (HC), and jugular tubercle (JT) were measured on anonymized Computed tomography angiography images previously obtained from 30 patients with pulsatile tinnitus. Full access to the JFR, and its medial, superior, and anterior aspects, could be adequately achieved via an EEA. Upon exiting the jugular foramen, the glossopharyngeal nerve courses posterior to the ICA, traveling inferiorly into the UPPS between ICA and IJV. The vagus nerve is in close proximity to the hypoglossal nerve traveling posterior to the ICA. The accessory nerve courses lateral to the vagus nerve, running posterior to the IJV. The minimal distances from the MPP to ICA, HC, and JT were 2.52 ± 0.34, 2.86 ± 0.36, and 3.18 ± 0.33 cm, respectively. This anatomical study strongly suggests the feasibility of using an EEA to access to the medial, superior, and anterior aspects of the jugular foramen and the adjacent UPPS. [ABSTRACT FROM AUTHOR]

Background: After internal carotid artery (ICA) injury during endoscopic skull base surgery, the majority of patients undergo ICA embolization or stenting to treat active extravasation or pseudoaneurysm development. However, management practices when embolization or stenting is not required have not been well described. The objective of this study was to determine how patients with ICA injury but no embolization, stenting, or ligation do long‐term and ascertain the reconstruction methods utilized. Methods: Twenty‐nine cases of ICA injury were identified in an international multi‐institutional retrospective review. Of these, we identified six cases that were not treated with embolization, stenting, or ICA sacrifice. Information was available for five cases. Results: A muscle patch was used in the immediate repair of each case. A nasoseptal flap was used in one case. Prefabricated nasal tampons were used in all cases. Nasal packing was initially left in for a median of 7 days prior to removal. The initial muscle patch was reinforced with a second muscle graft in one case. One case demonstrated ICA bleeding at the time of packing removal and was repacked an additional week. Follow‐up for each of these cases was at least 2 years. No cases of subsequent carotid rupture were found and none of these cases ultimately underwent endovascular stenting. Radiation or proton therapy has not been subsequently used in any of these patients. Conclusions: This study details the reconstruction, lessons learned, and long‐term follow‐up for five cases of ICA injury not treated with embolization, stenting, or ligation. [ABSTRACT FROM AUTHOR]

Objective: Determine the feasibility of accessing the internal maxillary artery (IMA) through a transorbital endoscopic assisted approach through the inferior orbital fissure (IOF). Materials and Methods: Six adult cadaveric specimens were injected intravascularly with colored latex and dissected on 12 sides. A transorbital endoscopic approach was used to expose the IOF and reach the IMA. Results: The average length and width of the anterolateral segment of the IOF were 7.3 and 4 mm, respectively, on the right side and 6.7 and 3.8 mm, respectively, on the left side. Surgical exposure and modification of the IOF allowed the exposure and control of the IMA in all 12 sides. Conclusions: The IOF is a feasible portal to the IMA. The benefits of this approach include vascular control of the distal segment of the maxillary artery. It may provide access in clinical scenarios where endonasal access is not possible (e.g., extensive tumors) or serve as an alternative or complementary surgical route (e.g., control during a total or radical maxillectomy). [ABSTRACT FROM AUTHOR]

https://bcove.video/33MDx0u [ABSTRACT FROM AUTHOR]

Endoscopic access to the petrous apex and petroclival region often requires sacrificing the Eustachian tube (ET). This study aimed to compare the maximum exposure of the petrous apex and petroclival region via an endonasal corridor when sparing or resecting the ET and its torus. Six cadaveric specimens (12 sides) were dissected through an endonasal transpterygoid approach. Endonasal exposure of the petroclival region was completed using techniques that included the preservation of the ET (group 1), resection of the torus tubarius (group 2), and resection of the ET (group 3) were sequentially performed on each side. The working distances from the anterior genu of the petrous internal carotid artery (ICA) to the inferior boundaries of each corridor were measured and compared. In group 1, the medial petrous apex and petroclival sulcus could be exposed with a working distance of 4.08 ± 0.67 mm. In group 2, the fossa of Rosenmüller, inferior petrous apex, and hypoglossal canal could be exposed, with a significantly increased working distance of 18.33 ± 0.89 mm (P =.001). In group 3, the exposure and ICA control was superior and offered a working distance of 20.67 ± 0.78 mm. No statistically significant difference derived from comparing groups 2 and 3 (P =.875). Resection of the torus tubarius can increase exposure of the petrous apex and petroclival region. It provides an alternative to resecting the ET, which might be beneficial for maintenance of middle ear function. ET resection, however, seems superior when ICA control is required. [ABSTRACT FROM AUTHOR]

Background: Recent reports have investigated the nascent role of induction chemotherapy for sinonasal undifferentiated carcinoma (SNUC). The goal of this study was to ascertain trends in treatment pattern changes for SNUC at a single institution and design a treatment algorithm utilized at our institution. Methods: Retrospective chart analysis of 21 cases of SNUC from 2010 to 2018. Results: Of 21 patients in this cohort, 18 (85.7%) presented with T4 disease, 7 (33.3%) presented with nodal disease, and 3 (14.3%) presented with distant metastasis. Since 2016, patients have been managed by induction chemotherapy followed by concurrent chemoradiation. To this point, patients treated with TPF induction chemotherapy followed by concurrent chemoradiation show no evidence of disease; however, the average follow up time is 16.8 months. Conclusions: The multimodality treatment for SNUC continues to evolve, as highlighted by this study, toward increased use of induction chemotherapy followed by chemoradiotherapy. [ABSTRACT FROM AUTHOR]

This study aimed to ascertain the maximal exposure of the superior orbital fissure (SOF) afforded by combining endonasal and transorbital endoscopic approaches. Six cadaveric specimens (12 sides) were dissected using endonasal and transorbital endoscopic approaches to access the SOF. The order of the approaches was alternated in each specimen (eg, starting with an endonasal approach in one side followed by a transorbital exposure and reversing the order on the contralateral side). Maximal exposure of the SOF and its contents for individual and combined approaches were explored. The endonasal corridor provided adequate access to the inferomedial 1/3 of the SOF and including the proximal segments of cranial nerves (CN) III, V1 and VI. A transorbital approach was superior accessing the superolateral 2/3's of the SOF, including the superior ophthalmic vein, lacrimal nerve, and distal segment of the CN VI at the lateral aspect; the nasociliary nerve and divisions of CN III centrally; and the frontal nerve and CN IV at the dorsal aspect of levator palpebrae superioris. This study suggests that a combined endonasal and transorbital exposure of the SOF may be advantageous to address lesions in this challenging region. [ABSTRACT FROM AUTHOR]

Background: Lesions of the upper parapharyngeal space (UPPS) present a surgical challenge. The objective of this study was to ascertain the feasibility of a novel technique of modified transpterygoid approach to the UPPS. Methods: Six fresh cadaveric specimens (12 sides) were dissected, developing a technique that includes en bloc mobilization of the lateral pterygoid plate and muscle to access the UPPS. Results: Following an endoscopic Denker's approach and the removal of posterolateral wall of the antrum, the lateral pterygoid plate was detached from the pterygoid process. Subsequently, the lateral pterygoid plate and muscle were displaced laterally as a unit, allowing the identification of the posterior trunk of V3 and the fat in prestyloid compartment. Dissecting off the styloid aponeurosis affords entering the poststyloid UPPS exposing the internal carotid artery, internal jugular vein, and cranial nerves IX to XII. Conclusion: This novel modification of the endonasal transpterygoid approach offers a viable alternative for access to the UPPS. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: The infratemporal fossa (ITF) represents an area densely packed with neurovascular structures within irregular boundaries. The goal of this study was to classify the ITF into zones corresponding to its anatomical spaces and the order in which they are encountered during an endonasal approach (anteroposterior axis). Methods: Six cadaveric specimens (12 sides) with injected colored latex were dissected. Following an endoscopic medial maxillectomy and Denker's approach, a progressive exploration of the masticator space and upper parapharyngeal space was completed. A classification of the ITF based on well‐defined spaces was ascertained. Results: The ITF was divided into five zones:Zone 1 (retromaxillary space)—space lying between the posterolateral wall of the maxillary sinus and the temporalis and pterygoid muscles.Zone 2 (superior interpterygoid space)—area including the superior head of the lateral pterygoid muscle, V3, and foramen ovale.Zone 3 (inferior interpterygoid space)—includes the inferior head of lateral pterygoid muscle, medial pterygoid, and temporalis muscles, and the space enclosed by these muscles.Zone 4 (temporo‐masseteric space)—space lateral to the temporalis muscle (comprising fat mostly).Zone 5 (tubopharyngeal space)—includes the Eustachian tube, tensor, and levator veli palatini muscles, and structures in upper parapharyngeal space. Conclusion: The ITF can be visualized as five zones based on spaces enclosed by the masticator muscles and upper parapharyngeal structures. This novel classification system is useful to guide endoscopic approaches to the ITF, while decreasing the potential for injury of neurovascular structures and pterygoid muscles. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 32-year-old female patient and discusses considerations for performing endoscopic surgery of the skull base which takes into consideration the pharyngobasilar fascia (PBF) submucosa membrane. Topics discussed include use of PBF in reduction of time and improvement in the accuracy of lacerum internal carotid artery localization, anatomical considerations of the PBF and details on the triangulation technique.

Objectives/hypothesis: To evaluate the potential of a minimally invasive transoral-transpalatal approach (MITA) to the retrocarotid petrous apex, as an adjunct to endoscopic endonasal approaches (EEAs).Study Design: Cadaver study.Methods: Five cadaveric specimens were dissected raising an inverted U-shaped palatal mucoperiosteal flap, and drilling a rectangular palatotomy (between the greater palatine foramens, and just anterior to the palatine aponeurosis). This allowed a transpterygoid EEA with cross-court access (contralateral line of sight), followed by an extradural clivectomy that exposed the petroclival junction bilaterally. Surgical targets were marked on the posterior and medial surface of the petrous internal carotid artery (ICA), at its anterior genu, midhorizontal portion, and posterior genu. For each target and approach, the surgical freedom and angles of approach (in the horizontal and vertical planes) were calculated and statistically compared.Results: Compared to EEA, the MITA resulted in greater surgical freedom for all targets, with the highest values at the anterior genu (1,661.37 mm2 vs. 312.76 mm2 , P <.001), and maintaining superiority in this regard all the way to the posterior genu (847.84 mm3 vs. 138.91 mm3 , P < .005). MITA also offered greater angles of approach for all targets.Conclusions: This study suggests that the MITA may be indicated to supplement the exposure provided by a transpterygoid EEA. This technique, associated with low potential morbidity, offers an alternative to internal carotid lateralization while managing extradural lesions that are adjacent to the petrous ICA.Level Of Evidence: NA Laryngoscope, 129:339-343, 2019. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Define the anatomic distribution of the olfactory filaments within specific mucosal regions of the nasal cavity.Study Design: Cadaveric study.Methods: Seventeen cadaveric specimens (34 sides) were dissected to study the anatomical distribution and density of olfactory fila within different regions of the nasal cavity. Olfactory fila were dissected retrogradely to their point of entry into the anterior cranial fossa through the cribriform plate. Anatomic relationships among various components of the olfactory system and their corresponding arterial supply were determined subjectively.Results: The highest density of olfactory fila was found at the mucosa of the ethmoid roof and superior turbinates. Olfactory fila were found at regions not previously considered to be part of the olfactory system: lateral wall of the nose, ethmoidal bullae, and between the os sphenoidale and arc of the posterior choana. Furthermore, at the septum, 20% of the olfactory fila crossed contralaterally before exiting the nose. The anterior ethmoidal arteries were the primary blood supply to the olfactory epithelium.Conclusions: This study suggests that olfactory filaments extend beyond previously established boundaries. These findings may have clinical implications regarding oncologic resections and could serve as the foundation for the development of techniques that better preserve olfactory function.Level Of Evidence: NA Laryngoscope, 2473-2477, 2018. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: To demonstrate anatomic relationships of the far-medial transoral endoscopic assisted approach (FMT-EAA) to the infratemporal fossa (ITF) and define the corridor dimensions, surgical freedom, and limitations associated with this approach.Study Design: Cadaveric study.Methods: Twenty ITFs (10 specimens) were dissected with the assistance of 0 °, 30 °, and 45 ° rod-lens endoscopes. Image guidance was used to confirm and measure the corridors' structural boundaries and document the anatomical relationships encountered in this approach.Results: Access to the ITF via the FMT-EAA can be divided into two secondary surgical corridors: the superomedial and inferolateral triangles, each of which provides access to different areas. The superomedial triangle is bounded medially by the lateral pterygoid plate and posterolateral maxillary sinus wall, superiorly by the greater sphenoid wing, and inferolaterally by the lateral pterygoid muscle. The inferolateral triangle is bounded superiorly by the lower head of the lateral pterygoid muscle, inferiorly by the medial pterygoid muscle, and laterally by the mandible. Using a standard 19-mm endoscope, the FMT-EAA achieves a mean surgical freedom of 231 mm and 161 mm in the vertical and horizontal planes, respectively.Conclusions: FMT-EAA adequately exposes critical structures of the ITF. This technique is a viable option for the management of selected ITF lesions, either alone or in combination with alternative minimally invasive approaches to the region.Level Of Evidence: NA Laryngoscope, 128:2273-2281, 2018. [ABSTRACT FROM AUTHOR]

Abstract: Background: When locoregional flaps fail to reconstruct the skull base, the microvascular surgeon faces several reconstructive challenges. We present our technique and results of salvage anterior skull base reconstruction utilizing the vastus lateralis free tissue transfer (VLFTT). Methods: Four patients with anterior skull base defects after previous locoregional flap failure underwent free tissue transfer reconstruction with VLFTT. Results: The success rate of free tissue transfer was 100%. Complete separation of the intracranial and sinonasal cavities was achieved in all patients; thus, resolving the cerebrospinal fluid (CSF) leakage in all patients. The VLFTT was inset through a minimally invasive approach utilizing an anterior maxillotomy via a gingivobuccal incision, an endoscopic medial maxillectomy, and endoscopic inset in all patients. No vein grafts were needed. Conclusion: This technique permits endoscopic endonasal inset and placement of reliable, well vascularized free tissue that may be utilized for complex, secondary reconstruction of the skull base. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Others have reported olfactory disturbances following endoscopic approaches to the skull base. However, there is a lack of consensus on the extent and duration of dysfunction. This study aimed to compare our results with previously published work and to validate the olfactory strip-sparing approach.Study Design: Prospective study to assess olfaction in 50 patients scheduled to undergo resection of skull base tumors via extended endoscopic approaches.Methods: Patients were divided into two groups. Group I had a nasoseptal flap (NSF), and group II included patients in whom rescue flaps were performed bilaterally. Olfactory outcomes were assessed using repeated University of Pennsylvania Smell Identification Test at baseline, 6 weeks, 3 months, and 6 months following surgery.Results: Ultimately, 42 patients (seven group I and 35 group II) were available for assessment. Scores for group I were lower than at baseline at 6 weeks postoperatively (30.71 ± 5.5 vs. 24.5 ± 5.4; P = .05). However, by the third postoperative month the scores had improved to a level that was not significantly different from baseline (29.0 ± 3.7; P = .5). At 6 months, the score was 30.0 ± 3.9. Patients in group II showed no difference between their baseline and 6-week scores (31.5 ± 5.3 vs. 29.7 ± 5.9; P = .16). Six months postoperatively, the score was significantly higher (33.78 ± 3.6; P = .04).Conclusions: Expanded endoscopic approaches to skull base tumors involving reconstruction with an NSF are associated with a short-term negative impact on olfaction. Olfaction does not seem to be affected by the surgical resection of pituitary adenomas associated with rescue flaps. Identification of the olfactory epithelium and meticulous harvesting of the NSF are critical to preserve olfaction.Level Of Evidence: 4. Laryngoscope, 127:1970-1975, 2017. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study is to demonstrate the potential contribution of positron emission tomography (PET)/computed tomography (CT) to help differentiate olfactory neuroblastoma (ONB) from sinonasal undifferentiated carcinoma (SNUC).Methods: Following approval by the institutional review board at the Wexner Medical Center at the Ohio State University, Columbus, Ohio, a pilot study with retrospective review of patients with biopsy-proven diagnosis of ONB s and SNUC s was conducted. Staging PET/CT scans were reviewed to document the maximum standardized uptake value (SUVmax). A statistical comparison of SUVmax was performed.Results: We identified 13 patients (7 with ONBs and 6 with SNUCs) with mean age 60.2 years who had undergone staging F-18 fluorodeoxyglucose (18 F-FDG) PET/CT of the primary tumor at the time of their diagnosis. Mean SUVmax was found to be five-fold higher in SNUC patients (35.63, range 10.8-77.9) than in ONB patients (7.24, range 4.6-10.7) (P ≤ 0.00169).Conclusion: Maximum standardized uptake value of 18 F-FDG PET/CT can be used to initially discriminate between ONB and SNUC. This finding may prove helpful to guide diagnostic and treatment planning when the histopathologic diagnosis is inconclusive.Level Of Evidence: 4. Laryngoscope, 2016 127:321-324, 2017. [ABSTRACT FROM AUTHOR]

Objectives: As the adoption of endoscopic endonasal approaches (EEA) continues to proliferate, increasing numbers of internal carotid artery (ICA) injuries are reported. The objective of this study was to develop a synthetic ICA injury-training model that could mimic this clinical scenario and be portable, repeatable, reproducible, and without risk of biological contamination.Methods: Based on computed tomography of a human head, we constructed a synthetic model using selective laser sintering with polyamide nylon and glass beads. Subsequently, the model was connected to a pulsatile pump using 6-mm silicon tubing. The pump maintains a pulsatile flow of an artificial blood-like fluid at a variable pressure to simulate heart beats. Volunteer surgeons with different levels of training and experience were provided simulation training sessions with the models. Pre- and posttraining questionnaires were completed by each of the participants.Results: Pre- and posttraining questionnaires suggest that repeated simulation sessions improve the surgical skills and self-confidence of trainees.Conclusion: This ICA injury model is portable; reproducible; and avoids ethical, biohazard, religious, and legal problems associated with cadaveric models. A synthetic ICA injury model for EEA allows recurring training that may improve the surgeon's ability to maintain endoscopic visualization, control catastrophic bleeding, decrease psychomotor stress, and develop effective team strategies to achieve hemostasis.Level Of Evidence: NA Laryngoscope, 127:38-43, 2017. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: Access to the frontal sinuses is technically challenging owing to their anterosuperior location, diverse anatomy, close proximity to critical structures and the need to work in a relatively narrow space with angled-lens endoscopes and instruments. This study attempts to study the relationship of the first olfactory fiber with the frontal sinus posterior wall, assessing its fidelity as a surgical landmark during frontal sinus surgery.Study Design: Anatomic study.Methods: Fifteen cadaveric specimens were studied. Measurements were obtained bilaterally using the data from individual CT scans. Median A-P was defined as the anteroposterior (A-P) diameter measured just lateral to the intersinus septum, paramedian A-P was measured 5 mm lateral to the septum, and maximum A-P was defined as the maximum anteroposterior diameter on axial images. A surgical navigation device was used to calculate the distance between the first olfactory fiber and the posterior table of the frontal sinus.Results: The mean distance between the first olfactory fiber and the posterior wall of the frontal sinus was (4.03 ± 2.7) mm on the right side and (4.2 ± 2.9) mm on the left. This distance strongly correlated with the maximum A-P diameter of the sinus.Conclusions: In a cadaveric model, the first olfactory fiber was found to be an average of 4.0 mm posterior to the frontal sinus. The significant variability of this distance should be considered when using the first olfactory fiber to establish the posterior boundary of a frontal sinusotomy. Drilling no further posterior than 7 mm rostral to the first olfactory fiber would be safe in 91% of patients.Level Of Evidence: NA Laryngoscope, 126:1039-1045, 2016. [ABSTRACT FROM AUTHOR]

Background The quadrangular space permits an anterior entry into Meckel's cave while obviating the need for cerebral or cranial nerve retraction. This avenue is intimately associated with the cavernous sinus; thus, from this ventral perspective, it is feasible to visualize the anteromedial, anterolateral, and Parkinson triangles. Methods Twenty middle cranial fossae were dissected endonasally under direct endoscopic visualization. Measurements of the surface area of the quadrangular space and the ventrally accessible cavernous sinus triangles were performed using 3 coordinates under image-guided navigation. Results The surface area of the quadrangular space was 16.36 mm2 (±2.89 mm2). The anterolateral triangle was the largest (47.27 ± 5.37 mm2), whereas Parkinson's was the smallest (22.46 ± 5.54 mm2); the anteromedial triangle presented an average surface area 36.07 mm2 (±4.15 mm2). Conclusion The trajectory of the internal carotid artery (ICA) significantly impacts the quadrangular space area and may be a potential parameter for defining the feasibility of this corridor. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1680-E1687, 2016 [ABSTRACT FROM AUTHOR]

Background Local recurrence, and regional and distant metastases, respectively, develop in 30% and 15% of patients with esthesioneuroblastoma (ENB). Methods This case report includes 3 patients with unusual recurrences of ENB in the sinonasal tract. Results Patient 1 developed ENB in the bilateral maxillary sinuses after unilateral endoscopic resection of a left ENB followed by postoperative proton radiotherapy. Patient 2 developed ENB at the left optic-carotid recess 7 years after a craniofacial resection and postoperative radiotherapy. Patient 3 developed ENB over the left zygomatic process of the maxilla 4 years after a cranioendoscopic resection and postoperative radiation therapy for ENB of the ethmoid sinuses with intracranial extension. The possibility of venous tumor emboli must be considered as a likely etiology. However, alternative explanations include the development of a second primary or potential transformation because of tumor signaling. Conclusion We present 3 cases that may represent metastasis of ENB within the sinonasal tract. © 2015 Wiley Periodicals, Inc. Head Neck 38: E32-E36, 2016 [ABSTRACT FROM AUTHOR]

The article presents a study related to endoscopic endonasal approach for maxillectomy. Topics discussed include complications in Caldwell-Luc procedure of treatment for sinonasal diseases, access to maxillary sinus by anterior maxillotomy, and limitation of endoscopic surgery like inaccessibility of anterior recesses of maxillary sinus, comparison of complications faced in sublabial maxillotomy and endoscopic endonasal anterior maxillotomy like cheek swelling, cheek dissection, and pain.

Objectives/Hypothesis This cadaveric study analyzes the endoscopic endonasal anatomy of the ophthalmic division of the trigeminal nerve (V1), from the middle fossa to its orbital entry via the superior orbital fissure. Anatomical relationships with the surrounding cranial nerves and blood vessels are described, with emphasis on their clinical correlation during surgery in this region. Our objective was to describe the anatomical relationships of the ophthalmic division of the trigeminal nerve. Study Design Cadaveric study. Methods Thirty middle cranial fossae, in adult human cadaveric specimens, were dissected endonasally under direct endoscopic visualization. During the dissection, we noted the relationships of the V1 nerve with the other trigeminal branches, as well as with the oculomotor and trochlear nerves, the paraclival and cavernous portions of the internal carotid artery, and the superior orbital fissure (SOF). Results The V1 nerve is the most superior trigeminal branch and runs upward and obliquely, along the middle portion of the lateral wall of the cavernous sinus. The V1 nerve joins the oculomotor and trochlear nerves to exit the cavernous sinus and enter the orbit through the SOF. Ten percent of the specimens displayed the trochlear nerve running along as a mate of the V1 nerve. The V1 nerve borders two key triangles in the lateral wall of the cavernous sinus, and the Parkinson's and anteromedial triangles. Conclusions In this study, the V1 nerve was a constant and reliable landmark, thus allowing the identification of the anteromedial triangle. This potential space can serve as an adequate window to access the temporal lobe. Knowledge of this anatomy is essential when planning and executing endonasal surgery in this region. Level of Evidence NA Laryngoscope, 125:1284-1290, 2015 [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis Endonasal approaches to the pterygopalatine fossa for epistaxis or as part of a transpterygoid approach have been popularized somewhat by the ability to control the terminal branches of the maxillary artery (MA). Surgical landmarks are useful to identify these arteries. Therefore, identification of surface features on the posterior wall of the antrum that reflect the position of deeper structures within the pterygopalatine fossa would help predict anatomical position and orientation. Study Design Describe the incidence of identifiable markings on the posterior wall of the maxillary sinus and ascertain their nature. Methods An anatomical study of 18 cadaveric specimens noting and recording the presence, location, and number of prominences on the posterior wall of the antrum. After removing the bony wall, structure in the pterygopalatine fossa corresponding to the surface markings was noted. Results Two prominences were identified. Prominence (P)1 extended from the upper part of the posterior wall of the maxillary sinus to the inferior orbit and corresponded to the infraorbital nerve. P2 was located at the middle part of the posterior wall, below P1, and corresponded to the MA. P2 was located medial to a vertical 'drop line' where P1 connected to the posterior wall. P1 and P2 were found in 41.7% and 22.2%, respectively, of the specimens. Conclusions This study defines features on the maxillary sinus posterior wall from an endoscopic perspective. These landmarks may be useful to identify the MA and its branches during surgery within the pterygopalatine fossa. Level of Evidence N/A. Laryngoscope, 124:2451-2455, 2014 [ABSTRACT FROM AUTHOR]

Background Pneumocephalus occurs as a result of traumatic or iatrogenic violation of the dura. Tension pneumocephalus, whereby air continues to accumulate with no mechanism for escape, can cause significant morbidity and mortality. Methods This case report reviews the underlying pathophysiology, clinical presentation, diagnosis, and management of tension pneumocephalus. Results We present the case of a 68-year-old man who presented to the Emergency Department with headache thought to be the result of a newfound intracranial mass. After admission, he became obtunded and was found to have tension pneumocephalus requiring emergent evacuation. A cervical esophagus carcinoma caused an esophageal-subarachnoid fistula that resulted in tension pneumocephalus after a retching episode. Conclusion This case illustrates the importance of considering alternative sources of pneumocephalus in the absence of more typical differential diagnosis. © 2013 Wiley Periodicals, Inc. Head Neck 36: E52-E56, 2014 [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis In an effort to decrease morbidity, skull base surgeons have explored less invasive approaches to the infratemporal fossa, including endonasal-endoscopy, minicraniotomies, and transantral endoscopic and microscopic corridors. This project presents quantitative data that assesses the practicality, and volumetric exposure afforded by endonasal and open approaches to the infratemporal fossa. Study Design First, the study defines the anatomy of endoscopic-endonasal and preauricular approaches to the infratemporal fossa. Subsequently, the study involved the calculation of anatomical volumes using cadaveric and virtual models. Methods Computed tomography (CT) scanning of two anatomical specimens served to recreate computer simulations of the endonasal and preauricular approaches, allowing for the assessment of the infratemporal fossae volumes. In addition, the dissections served to identify and mark critical surgical landmarks and boundaries. A second CT scan, after the surgical dissection, allowed for a reanalysis of the data for a volumetric comparison of the surgical approaches. Results Pre- and postdissection CT scans and computer simulations revealed that volumes in the open and endonasal approaches to the infratemporal fossa are strikingly similar, suggesting that volumes of surgical instrumentation and visualization may also be comparable. However, the entry gate for instrumentation differed significantly for each approach. Conclusion This study suggests that, although the entry gate for instrumentation is greater during an open approach, contrary to intuition, an open approach does not create a substantially larger working space or visual field. Analysis of volumetric measurements facilitates a better understanding of the indications for each procedure. Level of Evidence N/A. Laryngoscope, 124:1090-1096, 2014 [ABSTRACT FROM AUTHOR]

The article presents a study on the transposition of nasoseptal flap pedicle to reduce defects following endoscopic endonasal skull base surgery. It discusses the materials and methods for the surgery, results of the surgery, and discussion about nasoseptal flap (NSF) and endoscopic endonasal approaches (EEA). It concludes that the modified bipedical flap provides access to the sphenoid sinus and clivus.

Objectives/Hypothesis A pedicled nasoseptal flap is our preferred reconstructive technique after endoscopic endonasal skull base surgery. Its harvesting implies that the donor site (septal cartilage) is left bare. Secondary healing leads to crusting at the donor site that negatively affects the patient's quality of life and requires multiple outpatient debridements. A nasoseptal reverse rotation flap was designed to eliminate this problem; however, its outcomes have not been reported. Study Design Retrospective review. Methods We retrospectively reviewed the clinical charts of patients who underwent endoscopic endonasal skull base surgery at the Wexner Medical Center at The Ohio State University from November 2010 to September 2012, and in whom a reverse flap was used. We analyzed patients' demographics, pathology, and outcomes regarding the reverse flap. Results Forty-nine patients with various pathologies were included (11 meningiomas, seven craniopharyngiomas, five pituitary macroadenomas, five chondrosarcomas, five meningoencephaloceles, three chordomas, 11 malignant tumors, two other lesions). There were two patients lost to follow-up. Mean follow-up time was 11 weeks (range = 1-39 weeks). A follow-up examination 1 to 2 weeks after surgery revealed a complete re-epithelialization in 46 of 47 patients (97.87%). Adverse events included granuloma (n = 1), anterior dehiscence (n = 1), and excoriated mucosa (n = 1). Factors such as underlying disease, prior chemoradiotherapy, and postoperative chemoradiotherapy did not seem to affect the healing of the reverse flap. Conclusions The reverse flap provides complete remucosalization of the denuded donor septum, decreasing septal crusting within the first 1 to 2 postoperative weeks, and adds minimal morbidity. Level of Evidence 4 Laryngoscope, 123:2601-2604, 2013 [ABSTRACT FROM AUTHOR]

Background Oncologic resection of the clivus, nasopharynx, craniovertebral junction, and infratemporal fossa is a challenging endeavor because of their complex and protected anatomy. Our goals were to design a cadaveric model and identify advantages and limitations of combining the transoral robotic surgery (TORS) and endoscopic endonasal approach (EEA) techniques. Methods Cadaveric specimens were dissected using a da Vinci surgical robot and endoscopic endonasal instruments in a fashion that mimicked our operating room environment. We then applied these techniques clinically. Results EEA was performed to provide a detailed dissection of the infratemporal fossa, nasopharynx, posterior skull base (clivus), and craniovertebral junction. Using TORS, we dissected the parapharyngeal space, infratemporal fossa, and nasopharynx below the eustachian tube, which represented a transition zone that delineated the most effective resection field of each approach. Conclusions TORS and EEA seem to be complementary techniques; thus, their combined use seems advantageous for selected advanced tumors in these complex areas. © 2013 Wiley Periodicals, Inc. Head Neck, 35: E351-E358, 2013 [ABSTRACT FROM AUTHOR]

The article presents a study which explored the use of transoral, transpalatal, transnasal camera corridors and Endowrist instrument ports in a combined endoscopic endonasal approaches (EEA)-transoral robotic surgery (TORS) for the skull base. A da Vinci Surgical System with a Mayfield 3-pin fixation system was utilized in the dissection, followed by the EEA-TORS approach to start bone drilling and lateral access to the Eustachian tube (ET).

Background Oncologic resection of the nasopharynx is challenging due to its complex and deep-seated nature. We aimed to illustrate the anatomic landmarks of endoscopic nasopharyngectomy and design a surgical training model that could facilitate learning of this technique. Methods An endoscopic endonasal dissection of the nasopharynx was completed in fresh cadaveric specimens under conditions similar to those of our operating suite. Digital data from a high-resolution CT scan were imported to an image guidance system to be used during the dissections. Results We expanded the sinonasal corridor, harvested a contralateral nasoseptal flap, and exposed the pterygopalatine and infratemporal fossae. A detailed anatomic dissection of the nasopharynx was correlated to multiplanar images provided by the image guidance system, highlighting appropriate bony, neural, and vascular landmarks. Conclusions Understanding the anatomy-based endoscopic modular approaches facilitates planning and safe execution of an oncologic nasopharyngectomy. Clinical experience remains mandatory because anatomic models fall short of clinical scenarios. © 2012 Wiley Periodicals, Inc. © 2012 Wiley Periodicals, Inc. Head Neck, 2013 [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: Endoscopic endonasal transpterygoid approaches (EETA) use the pneumatization of the sinonasal corridor to control lesions of the middle and posterior skull base. These surgical areas are complex and the required surgical corridors are difficult to predict. Aim: Define anatomical landmarks for the preoperative planning of EETAs. Study design: Anatomical study. Methods: We reviewed images from high-resolution maxillofacial CT scans with (0.6-mm axial slice acquisition). Cephalometric measurements were obtained using Kodak Carestream Image Software (Rochester, NY). Results: Average distance from midline to the vidian canal was 12.78 mm (range 9.4-15.8 mm). Average horizontal distance from the vidian canal to the foramen rotundum was 5.6 mm (range 2.8-11.5 mm). Average vertical distance from the vidian canal to the foramen rotundum was 6.22 mm (range 4.3-9.3 mm). These landmarks are consequential during the preoperative planning of the surgical corridor. To facilitate communication, we classified EETAs as: A) Partial removal of the pterygoid plates (transposition of temporo-parietal fascia); B) removal of anteromedial aspect of the pterygoid process (lesions involving the lateral recess of the sphenoid sinus); C) involves dissecting the vidian nerve to control the petrous ICA and removing the pterygoid plates base to reach the petrous apex, Meckel's cave, or cavernous sinus; D) variable removal of the pterygoid plates to access the infratemporal fossa; and E) removal of pterygoid process and medial third of the Eustachian tube to expose the nasopharynx. Conclusions: Our novel classification and landmarks system helps to understand the anatomy of this complex area and to accurately plan the EETA. [ABSTRACT FROM AUTHOR]

Background The infratemporal fossa anatomy, from an endoscopic standpoint, is poorly understood. Our purpose was to design an anatomic model that illustrates the anatomy of the infratemporal fossa from the endoscopic standpoint and serves as a training model for surgeons interested in pursuing this endeavor. Methods Red and blue silicone dyes were respectively injected into the great vessels of the neck. Digital data acquired from a high resolution CT scan was imported to a navigational system. An endoscopic endonasal dissection of the infratemporal fossa was completed under conditions that mimicked our operating suite. Results A detailed anatomic dissection of the infratemporal fossa was correlated to the image guidance (navigation) system. This provided a surgical map highlighting critical neurovascular structures and illustrating the potential surgical corridors. Conclusion A thorough understanding of the anatomy of infratemporal fossa from the endoscopic perspective allows the surgeon to plan an adequate corridor. © 2011 Wiley Periodicals, Inc. Head Neck, 2012 [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: The aim of this work was to define the anatomical landmarks, limitations, and difficulties of obtaining internal carotid artery (ICA) exposure via endonasal endoscopic approaches (EEA). Study Design: Cadaveric descriptive study. Methods: The ICA was dissected via EEA in 10 cadaveric specimens (20 sides) prepared with intravascular injections of colored silicone. We carried the ICA dissection from the cavernous to the distal parapharyngeal segments through a transpterygoid corridor. Results: The transpterygoid approach provided adequate exposure of the lacerum and horizontal petrous ICA. Additional exposure of the ICA and the infrapetrous area required resection of the eustachian tube (ET) and the fibrocartilaginous tissue of the foramen lacerum after a medial maxillectomy and resection of the pterygoid plates. The main anatomical landmarks to the corresponding ICA segment include: the vidian nerve that points to the lacerum and horizontal segments, the mandibular nerve (V3) that heralds the petrous segment, the foramen ovale and the ET that signal toward the carotid canal, and the posterior trunk of the mandibular nerve (V3) and the ET that mark the parapharyngeal segment. Conclusions: EEAs provide access to the ICA from its cavernous to the distal parapharyngeal segments. A stepwise approach is critical to its exposure and control. Surgeons must be aware of its frequently tortuous three-dimensional course and the intimate relation of the vessel to the carotid canal and the cartilage of the foramen lacerum. [ABSTRACT FROM AUTHOR]

Objective: Describe our technique for endoscopic transpterygoid nasopharyngectomy and support its feasibility with our early clinical outcomes. Methods: Our endoscopic technique comprises an extended inferomedial maxillectomy, mobilization of the pterygopalatine fossa, removal of the pterygoid plates and Eustachian tube to access the posterolateral nasopharynx. Control of the parapharyngeal and petrous segments of the internal carotid artery is the keystone of the approach. Results: Various histopathologies were treated, including epidermoid carcinomas (n = 9), lymphoepithelioma (n = 1), adenoid cystic carcinoma (n = 5), adenocarcinoma (n = 2), mucoepidermoid carcinoma (n = 2), and sarcoma (n = 1). Negative microscopic margins were obtained in 95% (19/20) of patients. No perioperative mortality, cerebral spinal fluid (CSF) leak, meningitis, or cerebrovascular accident was encountered; however, one patient suffered an internal carotid artery (ICA) injury, without permanent sequelae. All but one patient received adjuvant therapy (external and/or stereotactic radiotherapy with or without chemotherapy). Follow-up ranged from 15 to 68 months (mean = 33). Overall survival was 45% (9/20) and local control was 65% (13/20). Conclusions: Endoscopic transpterygoid nasopharyngectomy for primary and recurrent nasopharyngeal malignancies is feasible and safe in properly selected patients. Preliminary outcomes compare to that of conventional techniques. Endoscopic resections, however, are demanding; they require specialized equipment and a team versed in endoscopic oncologic surgery. Long-term follow-up and reproducibility remain undefined. [ABSTRACT FROM AUTHOR]

Objectives: Expansion of the clinical indications for ablative endoscopic endonasal approaches has behooved us to search for new reconstruction alternatives. We present the anatomic foundations of a novel anterior pedicled lateral wall flap (Hadad-Bassagaisteguy 2 or HB2 flap) for the vascularized reconstruction of anterior skull base defects. Study Design: Anatomic description. Feasibility study. Technical report Methods: Using a cadaveric model, we investigated the feasibility of harvesting an anteriorly based mucoperiosteal flap from the lateral nasal wall. We then applied the techniques developed in the anatomical laboratory to reconstruct two patients with defects resulting from the endoscopic endonasal resection of esthesioneuroblastomas and one patient with an extensive meningoencephalocoele of the anterior cranial fossa. Results: HB2 flaps were harvested and transposed to reconstruct anterior skull base defects in cadaveric specimens, and subsequently, in three patients. The HB2 flap provided adequate coverage in the cadaveric model, as well as clinically in our three patients. Their postoperative healing was uneventful. Conclusions: The HB2 flap is a feasible alternative for the reconstruction of anterior skull base defects in select patients. [ABSTRACT FROM AUTHOR]