Pinheiro‐Neto, Carlos

ObjectiveWhile pedicled intranasal flaps, such as the nasoseptal flap (NSF), successfully reduce postoperative CSF leaks following endoscopic endonasal approaches (EEA) to the skull base, morbidity remains prevalent. This study describes the first cadaveric description and radiographic analysis of the posterior septal nasal floor mucosal flap (PSNF) designed to reduce pedicled nasal flap morbidity. A case series is also detailed.Study DesignCadaveric dissection, radiographic analysis, and case series.MethodsSeven cadaver specimens underwent harvest of the PSNF. PSNF flap dimensions were measured on the thirty deidentified sinus computed tomography (CT) scans. A retrospective case series was performed on the first set of patients who received the PSNF for reconstruction of a sellar base defect. Information concerning complications, symptoms, and the appearance of the flap was recorded from records of the patient's postoperative inpatient stay, 1‐week postop visit, and 1‐month postop visit.ResultsCadaver dissection of the PSNF flap demonstrated good arc rotation along its pedicle with ability to cover both sellar and planum defects. Cadaveric flap measurements and CT‐derived measurements estimated a mean surface area of 16.7 and 18.3 cm2, respectively. 15 patients underwent reconstruction of a sellar or planum defect using the PSNF technique. Only one CSF leak was encountered postoperatively. Minimal crusting of the flap and donor site was seen 1 month postoperatively.ConclusionThe PSNF flap provides a sizeable pedicled region for reconstruction comparable to other pedicled nasal flaps. Our case series demonstrated good postoperative outcomes without reduced donor site morbidity.Level of Evidence4 Laryngoscope, 132:1561–1568, 2022

Abstract Introduction Although endonasal endoscopic approaches (EEA) to the orbit have been previously reported, a didactic resource for educating neurosurgery and otolaryngology trainees regarding the pertinent anatomy, techniques, and decision-making pearls is lacking. Methods Six sides of three formalin-fixed, color latex–injected cadaveric specimens were dissected using 4-mm 0- and 30-degree rigid endoscopes, as well as standard endoscopic equipment, and a high-speed surgical drill. The anatomical dissection was documented in stepwise three-dimensional (3D) endoscopic images. Following dissection, representative case applications were reviewed. Results EEA to the orbit provides excellent access to the medial and inferior orbital regions. Key steps include positioning and preoperative considerations, middle turbinate medialization, uncinate process and ethmoid bulla removal, complete ethmoidectomy, sphenoidotomy, maxillary antrostomy, lamina papyracea resection, orbital apex and optic canal decompression, orbital floor resection, periorbita opening, dissection of the extraconal fat, and final exposure of the orbit contents via the medial-inferior recti corridor. Conclusion EEA to the orbit is challenging, in particular for trainees unfamiliar with nasal and paranasal sinus anatomy. Operatively oriented neuroanatomy dissections are crucial didactic resources in preparation for practical endonasal applications in the operating room (OR). This approach provides optimal exposure to the inferior and medial orbit to treat a wide variety of pathologies. We describe a comprehensive step-by-step curriculum directed to any audience willing to master this endoscopic skull base approach.

Abstract Background Despite the use of vascularized intranasal flaps, endoscopic endonasal posterior fossa defects remain surgically challenging with high rates of postoperative cerebrospinal fluid leak. Objective The aim of the study is to describe a novel surgical technique that allows complete drilling of the clivus and exposure of the craniovertebral junction with preservation of the nasopharynx. Methods Two formalin-fixed latex-injected anatomical specimens were used to confirm feasibility of the technique. Two surgical approaches were used: sole endoscopic endonasal approach and transnasion approach. The sole endonasal approach was used in a patient with a petroclival meningioma. Results In both anatomical dissections, the inferior clivectomy with exposure of the foramen magnum was achieved with a sole endoscopic endonasal approach. The addition of the transnasion approach helped to complete drilling of the inferior border of the foramen magnum and exposure of the arch of C1. Conclusion This study shows the anatomical feasibility of total clivectomy and exposure of the craniovertebral junction with preservation of the nasopharynx. A more favorable anatomical posterior fossa defect for the reconstruction is achieved with this technique. Further clinical studies are needed to assess if this change would impact the postoperative CSF leak rate.

Objective To provide a comprehensive state‐of‐the‐art review of the emerging role of urine leukotriene E4 (uLTE4) as a biomarker in the diagnosis of chronic rhinosinusitis (CRS), aspirin‐exacerbated respiratory disease (AERD), and asthma. Data Sources Ovid MEDLINE(R), Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus. Review Methods A state‐of‐the‐art review was performed investigating the role of uLTE4 as a diagnostic biomarker, predictor of disease severity, and potential marker of selected therapeutic efficacy. Conclusions uLTE4 has been shown to be a reliable and clinically relevant biomarker for CRS, AERD, and asthma. uLTE4 is helpful in ongoing efforts to better endotype patients with CRS and to predict disease severity. Implications for Practice Aside from being a diagnostic biomarker, uLTE4 is also able to differentiate aspirin‐tolerant patients from patients with AERD and has been associated with objective disease severity in patients with CRS with nasal polyposis. uLTE4 levels have also been shown to predict response to medical therapy, particularly leukotriene‐modifying agents.

Abstract BACKGROUND The lateral craniopharyngeal or Sternberg's canal (SC) originates from superior orbital fissure (SOF) and traverses the sphenoid body into the nasopharynx. A remnant of the canal, Sternberg's defect (SD), has been debated as a source of cerebrospinal fluid (CSF) leak. The canal was described in 1888, and there is limited accurate visual illustration in the literature. OBJECTIVE To provide a detailed anatomic and radiological illustration of the canal in pediatric and adult population including the mechanism undermining the incidence of the canal, and the possibility of the canal as a source of CSF leak. METHODS A total of 195 high-resolution computed tomographies (CT) of patients (50 3-yr-old, 20 5-yr-old, and 125 adults) and 43 dry adult skulls (86 sides) were analyzed for a canal matching the description of the SC. RESULTS A SC was identified in 86% of the 3-yr-old and 40% of 5-yr–old patients. The diameter and length were 2.12 mm and 12 mm, respectively. The incidence of the canal decreased with age as sinus pneumatization extended into the sphenoid sinus. Only 0.8% of the adult skull on CT had the canal. The canal was not present on the dry adult skulls examination, but SD was found in 4.65%. CONCLUSION SC exists with high incidence in the pediatric group. Sinus pneumatization obliterates the canal in the adult population, leaving a defect in 4.65% of cases, which given the location and related anatomic structures, is unlikely to be a source of CSF leak.