Faculty Bibliography

OBJECTIVES/HYPOTHESIS/OBJECTIVE:To describe anatomical landmarks for endoscopic endonasal approaches to the orbital apex and to measure the distances between those landmarks. METHODS:In this anatomic study, the nasal fossae of 30 adult fresh cadavers were dissected (n = 60 half-skulls). One double-injected orbit was carefully dissected, mainly focusing on the neurovascular structures. The orbital apex was dissected under endoscopic endonasal visualization in all cases. The distances between the ethmoidal crest and choanal arch to the optic canal (OC) and superior orbital fissure (SOF) were measured and recorded. RESULTS:The sample was predominantly male (63.3%, 19/30 cadavers). The following correlations between measurements according to side were observed: ethmoidal crest to OC, r = 0.748 (P = 0.0001); ethmoidal crest to SOF, r = 0.785 (P = 0.0001); choanal arch to OC, r = 0.835 (P = 0.0001); choanal arch to SOF, r = 0.820 (P = 0.0001). CONCLUSIONS:In the cadavers studied in this sample, the ethmoidal crest and choanal arch were relevant structures and exhibited consistent measurements. Spearman correlation coefficients were greater than 0.7, which is indicative of good correlation between measurements obtained in the skull halves of each cadaver. Comparison of the measurements obtained in different sides showed similar values, with no statistically significant differences in the distances between any of the proposed anatomic landmarks.

OBJECTIVE:Fractures of the orbital floor are common yet repaired by various techniques, including open periorbital, transantral endoscopic, and endoscopic endonasal approaches. To date, endoscopic endonasal repair of an orbital floor fracture using an alloplastic implant has not been described. We aim to determine the technique and limitations of completely endoscopic endonasal orbital floor repair using an alloplastic implant. STUDY DESIGN/METHODS:Cadaveric anatomic study and retrospective case series. METHODS:Cadaveric study of 12 sides with endoscopic sinonasal dissection followed by the creation and repair of an isolated orbital floor fracture using an alloplastic implant. Four representative patient cases are presented in which the techniques developed in the cadaveric study were employed. Patients were selected for this technique based on the results of the cadaveric study. RESULTS:Cadaveric study demonstrated feasibility of access and repair for fractures that did not extend lateral to the infraorbital canal or anterior to the nasolacrimal duct. In all cadaveric sides and in all 4 patient cases, successful alloplastic orbital floor reconstruction was achieved. CONCLUSION/CONCLUSIONS:This method of repair is feasible for selected patients and may be considered in cases of favorable fracture anatomy with or without concomitant indication for an ipsilateral sinus procedure.

BACKGROUND:The nasoseptal flap has revolutionized reconstruction of ventral skull base defects. The past decade is also noticeable by the evolution of transoral robotic surgery (TORS). Reconstruction of the oropharyngeal defect is challenging. Good reconstructive options with less cicatricial retraction are desirable and still lacking in the literature. METHODS:Cadaver dissection and illustrative case are used to show the feasibility of harvesting a nasoseptal flap to reconstruct oropharyngeal defect after radical tonsillectomy. Surgical resection included part of the soft palate and tongue base. RESULTS:The flap was sufficient to cover two-thirds of the tonsillar defect during the cadaver dissection. In our illustrative case, the flap filled the palatal defect and also was sufficient to cover the superior half of the tonsillar defect. CONCLUSION:The nasoseptal flap has shown to be feasible and reliable for reconstruction of the oropharyngeal defect after TORS. When soft palate resection is warranted, this flap provides excellent coverage. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2495-E2498, 2016.

BACKGROUND:Olfactory schwannomas of the anterior cranial base (ACB) are rare tumors, and their association with hereditary hemorrhagic telangiectasia (HHT) has not previously been described. The majority of ACB schwannomas arise from the sinonasal tracts and may demonstrate intracranial extension. We report a case of an olfactory schwannoma-dense adherence to the basal frontal lobe. Complete tumor resection was performed through a unilateral extended endonasal endoscopic approach with preservation of the contralateral olfactory bulb. Anterior cranial base repair was achieved with the use of a mucoperichondrial vascularized pedicled nasoseptal flap. CLINICAL PRESENTATION/METHODS:A 25-year-old woman with a history of migraines presented with unilateral epistaxis and progressive worsening of her headache symptoms. The patient had a history of HHT. Nasal endoscopy showed mild telangiectasias, but no clear evidence of a mass. A computerized tomographic scan showed a large left-sided expansile lesion in the left ethmoid region with expansion and remodeling of the anterior cranial base and medial left orbit. Magnetic resonance imaging with contrast showed the mass to be avidly enhancing. Angiography was performed and demonstrated a mild vascular blush. CONCLUSIONS:We report a rare case of HTT and olfactory schwannoma completely resected with a unilateral extended endoscopic endonasal approach. Reconstruction was performed with the use of nasoseptal flap. This is the first reported single-stage fully endoscopic endonasal unilateral approach for resection of an olfactory schwannoma with preservation of the contralateral olfactory cleft. The patient's sense of smell and taste was maintained after surgery.

The osteotemporoparietal fascia flap (OTPFF) has been used for bony defects, especially on the maxilla and orbital floor. However, there are limited reports about the reconstruction of the zygoma. We report the use of composite OTPFF for reconstruction of zygomaticomaxillary complex. The patient had undergone zygomaticomaxillary complex reconstruction with composite OTPFF because of the resection of recurrent postradiation tumor. Extratemporoparietal fascia was harvested and rotated to cover the medullary surface of the bone flap. Flap was successfully transferred with complete bone integration. There were no surgical complications and excellent cosmetic result. The patient is free of disease 12 months post surgery. The OTPFF seems to be a good option in zygomatic reconstruction, even in previously irradiated fields. Utilization of extratemporoparietal fascia to cover the medullary surface of the bone flap has potential to be an advantageous technique to minimize bone exposure and improve flap integration.

OBJECTIVES/HYPOTHESIS:To evaluate the increase in access to the maxillary sinus (MS) with transnasal endoscopic medial maxillary sinus wall transposition (TEMMT), while preserving major structures of the nasal cavity. STUDY DESIGN:The study was divided into three parts: anatomical, radiographic, and case series. METHODS:Three cadaveric dissections (total of six sides) confirmed the feasibility of the TEMMT approach. Radiographic measurements using maxillofacial computed tomography scans were taken to assess the maximal antrostomy. The TEMMT approach was performed on six consecutive patients with benign MS disease. RESULTS:The cadaveric measurements were consistent with the radiographic measurements, which confirmed the maximum access to the MS. The radiographic measurements ranged from 14.4 to 39.1 mm in the anteroposterior dimension, 8.2 to 23.7 mm in the superior-inferior dimension, and 36° to 98° in the angle between the medial and anterior wall of the MS. In the patient series, five patients presented with an odontogenic cyst, and one patient had an antrochoanal polyp in the MS. The TEMMT approach provided excellent access and adequate resection, as well as preservation of the nasolacrimal duct and inferior turbinate. Finally, the mucosal flap was sufficient to cover the inferior meatal antrostomy. CONCLUSIONS:TEMMT provides excellent access into the MS, especially the floor and anterior wall, without the morbidities of the Caldwell-Luc or medial maxillectomy approach. In addition, the transposition of the inferior turbinate and the mucosal flap provides coverage of the medial wall with preservation of the inferior meatus, inferior turbinate, and nasolacrimal duct for patients with benign MS disease. LEVEL OF EVIDENCE:NA Laryngoscope, 126:1504-1509, 2016.

OBJECTIVES/HYPOTHESIS/OBJECTIVE:To conceive and critically evaluate an adaptation of the split calvarial osteopericranial flap for reconstruction following endoscopic endonasal resection of the anterior skull base. STUDY DESIGN/METHODS:Cadaveric anatomic study. METHODS:Five cadavers were embalmed with methanol, and vasculature was injected with latex. Endoscopic endonasal resection of the anterior skull base was performed, followed by reconstruction with a unilateral osteopericranial flap and a contralateral conventional pericranial flap. RESULTS:Rigid reconstruction was achieved in all specimens. Osteoplastic flap harvest was made more reliable by drilling the diploe below the graft with a curved bur. Dimensions of the bony flap were ideally shorter and wider than the defect, allowing for flap inset and rigid support by the orbits without compromise of the flap vascular supply. Endoscopic inset of the flap is feasible via nasion-frontal osteotomy and inlay technique. CONCLUSION/CONCLUSIONS:Rigid anterior skull base reconstruction via split calvarial osteopericranial flap is adaptable to current endoscopic techniques. This provides more anatomic reconstruction than current methods and may lead to decreased complication rates following anterior skull base resection.

OBJECTIVES/HYPOTHESIS/OBJECTIVE:The goal of this study was to present a classification based on the degree of pneumatization of the sphenoid sinus in the coronal plane that can be used to instruct preoperative planning for endoscopic endonasal surgery (EES). STUDY DESIGN/METHODS:Observational anatomical study. METHODS:The geometry of sphenoid sinus pneumatization was characterized (n = 204 hemisinus) on high-resolution computed tomography scans, and its associations with the location of the foramen rotundum (FR) and the vidian canal (VC) were measured. Based on these findings, we propose a simple classification of pneumatization of the sphenoid sinus relevant for EES. RESULTS:The lateral recess of the sphenoid sinus was pneumatized lateral to the FR in the coronal plane in 54% of patients. The distance separating the FR and the VC correlated strongly with the depth of the lateral recess. Based on these findings, we propose three types of pneumatization: type I, where the pneumatization extends from the midline to the medial edge of the VC (25%); type II, where the pneumatization reaches the medial edge of the FR (39%); and type III, where the pneumatization extends beyond the medial border of the FR (37%). CONCLUSIONS:The proposed sphenoid sinus pneumatization classification in the coronal plane is simple and reproducible. It predicts the distance between vidian and maxillary nerve, determines the size of the surgical window to access the middle cranial fossa transnasally, and instructs on the potential risk to neurovascular structures during surgery.

Background Endoscopic endonasal surgery (EES) of the skull base often requires extensive bone work in proximity to critical neurovascular structures. Objective To demonstrate the application of an ultrasonic bone curette during EES. Methods Ten patients with skull base lesions underwent EES from September 2011 to April 2012 at the University of Pittsburgh Medical Center. Most of the bone work was done with high-speed drill and rongeurs. The ultrasonic curette was used to remove specific structures. Results All the patients were submitted to fully endoscopic endonasal procedures and had critical bony structures removed with the ultrasonic bone curette. Two patients with degenerative spine diseases underwent odontoid process removal. Five patients with clival and petroclival tumors underwent posterior clinoid removal. Two patients with anterior fossa tumors underwent crista galli removal. One patient underwent unilateral optic nerve decompression. No mechanical or heat injury resulted from the ultrasonic curette. The surrounding neurovascular structures and soft tissue were preserved in all cases. Conclusion In selected EES, the ultrasonic bone curette was successfully used to remove loose pieces of bone in narrow corridors, adjacent to neurovascular structures, and it has advantages to high-speed drills in these specific situations.