Significance of clinical-immunological patterns and diagnostic yield of biopsies in microscopic polyangiitis and granulomatosis with polyangiitis.

BACKGROUND: Microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) are the two major antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). OBJECTIVES: To characterize a homogenous AAV cohort and to assess the impact of clinicopathological profiles and ANCA serotypes on clinical presentation and prognosis. Clinical differences in GPA patients according to ANCA serotype and the diagnostic yield for vasculitis of biopsies in different territories were also investigated. RESULTS: This retrospective study (2000-2021) included 152 patients with AAV (77 MPA/75 GPA). MPA patients (96.1% myeloperoxidase [MPO]-ANCA and 2.6% proteinase 3 [PR3]-ANCA) presented more often with weight loss, myalgia, renal involvement, interstitial lung disease (ILD), cutaneous purpura, and peripheral nerve involvement. Patients with GPA (44% PR3-ANCA, 33.3% MPO, and 22.7% negative/atypical ANCA) presented more commonly with ear, nose, and throat and eye/orbital manifestations, more relapses, and higher survival than patients with MPA. GPA was the only independent risk factor for relapse. Poor survival predictors were older age at diagnosis and peripheral nerve involvement. ANCA serotypes differentiated clinical features in a lesser degree than clinical phenotypes. A mean of 1.5 biopsies were performed in 93.4% of patients in different territories. Overall, vasculitis was identified in 80.3% (97.3% in MPA and 61.8% in GPA) of patients. CONCLUSIONS: The identification of GPA presentations associated with MPO-ANCA and awareness of risk factors for relapse and mortality are important to guide proper therapeutic strategies in AAV patients. Biopsies of different affected territories should be pursued in difficult-to-diagnose patients based on their significant diagnostic yield.

EUFOREA/EPOS2020 statement on the clinical considerations for chronic rhinosinusitis with nasal polyps care.

Following the European Forum for Research and Education in Allergy and Airway Diseases (EUFOREA) treatment algorithm for chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP), patients suffering from severe uncontrolled CRSwNP are recommended to receive oral corticosteroids, (revision) sinus surgery, systemic biologicals and/or aspirin treatment after desensitization (ATAD). Given the major differences in indications, outcomes, practical considerations, risks and costs of these key pillars of treatment, there is a growing need to define criteria for each treatment option and list the clinically relevant and major considerations for them. This EUFOREA document therefore provides an expert panel overview of the expected outcomes, specific considerations and (contra)indications of the five major treatment arms of severe uncontrolled CRSwNP: oral corticosteroids, primary and revision sinus surgery, biological treatment and ATAD. This overview of treatment considerations is needed to allow physicians and patients to consider the different options in the context of providing optimal and personalized care for severe uncontrolled CRSwNP. In conclusion, the five major treatment options for severe uncontrolled CRSwNP have intrinsic advantages, specific indications and considerations that are of importance to the patient, the physician and the society. This EUFOREA statement supports the unmet need to define criteria for the indication of every treatment pillar of CRSwNP.

Type 2 and Non-type 2 Inflammation in the Upper Airways: Cellular and Molecular Alterations in Olfactory Neuroepithelium Cell Populations.

PURPOSE OF REVIEW: Neurogenesis occurring in the olfactory epithelium is critical to continuously replace olfactory neurons to maintain olfactory function, but is impaired during chronic type 2 and non-type 2 inflammation of the upper airways. In this review, we describe the neurobiology of olfaction and the olfactory alterations in chronic rhinosinusitis with nasal polyps (type 2 inflammation) and post-viral acute rhinosinusitis (non-type 2 inflammation), highlighting the role of immune response attenuating olfactory neurogenesis as a possibly mechanism for the loss of smell in these diseases. RECENT FINDINGS: Several studies have provided relevant insights into the role of basal stem cells as direct participants in the progression of chronic inflammation identifying a functional switch away from a neuro-regenerative phenotype to one contributing to immune defense, a process that induces a deficient replacement of olfactory neurons. The interaction between olfactory stem cells and immune system might critically underlie ongoing loss of smell in type 2 and non-type 2 inflammatory upper airway diseases. In this review, we describe the neurobiology of olfaction and the olfactory alterations in type 2 and non-type 2 inflammatory upper airway diseases, highlighting the role of immune response attenuating olfactory neurogenesis, as a possibly mechanism for the lack of loss of smell recovery.

Systematic Review of Long Term Sinonasal Outcomes in CRSwNP after Endoscopic Sinus Surgery: A call for Unified and Standardized Criteria and Terms.

PURPOSE OF REVIEW: To present current evidence in long-term (> 5 years) results after endoscopic sinus surgery (ESS) focusing on Patients Reported Outcome Measures (PROMs) and other sinonasal outcomes while assessing the role of ESS in the treatment of CRSwNP, and identifying outcomes which affect the results of ESS and defining recommendations for future studies. RECENT FINDINGS: Long-term results of ESS in CRSwNP can be branched in PROMs and other objective measurements. Despite the heterogeneity of reported outcomes make it difficult to perform comparisons and meta-analysis, ESS improves PROMs, including symptoms, QOL and olfaction. Objectives outcomes such as NPS, LMS, type of surgery, or recurrence and revision surgery don't have a clear role in long-term results. Clustering patients suggest asthma, N-ERD, allergy, eosinophil count and IL-5 could have a role in predicting recurrence and severe disease. Long-term studies of CRSwNP treated with ESS are scarce. There is a significant need to standardize the report of results. The use of tools as SNOT-22, NPS, validated smell tests, defined criteria for disease recurrence and control and ESS extension in a unified systematic way could allow better comparisons between treatments in the new era of biologics.

Complications of the Superior Eyelid Endoscopic Transorbital Approach to the Skull Base: Preliminary Experience With Specific Focus on Orbital Outcome.

BACKGROUND: The endoscopic superior eyelid approach is a relatively novel mini-invasive technique that is currently investigating for skull base cancers. However, questions remain regarding specific approach-related complications when treating different skull base tumors. This study aims to analyze any surgical complications that occurred in our preliminary consecutive experience, with specific focus on orbital outcome. METHODS: A retrospective and consecutive cohort of patients treated via a superior eyelid endoscopic transorbital approach at the Division of Neurosurgery of the Hospital Clinic in Barcelona was analyzed. Patients features were described in detail. Complications were divided into 2 groups to analyze separately the approach-related complications, and those resulting from tumor removal. The ocular complications were subdivided into early ocular status (<3 weeks), late ocular status (3-8 weeks), and persistent ocular complications. The "Park questionnaire" was used to determine patient's satisfaction related to the transorbital approach. RESULTS: A total of 20 patients (5 spheno-orbital meningiomas, 1 intradiploic Meningioma, 2 intraconal lesions, 1 temporal pole lesion, 2 trigeminal schwannoma, 3 cavernous sinus lesions, and 6 petroclival lesions) were included in the period 2017-2022. Regarding early ocular status, upper eyelid edema was detected in all cases (100%) associated with diplopia in the lateral gaze in 30% of cases, and periorbital edema in 15% of cases. These aspects tend to resolve at late ocular follow-up (3-8 weeks) in most cases. Regarding persistent ocular complications, in one case of intraconal lesion, a limitation of eye abduction was detected (5%). In another patient with intraconal lesion, an ocular neuropathic pain was reported (5%). In 2 cases of petroclival menigioma, who were also treated with a ventriculo-peritoneal shunt, slight enophthalmus was observed as a persistent complication (10%). According to the Park questionnaire, no cosmetic complaints, no head pain, no palpable cranial irregularities, and no limited mouth opening were reported, and an average of 89% of general satisfaction was encountered. CONCLUSIONS: The superior eyelid endoscopic transorbital approach is a safe and satisfactory technique for a diversity of skull base tumors. At late follow-up, upper eyelid edema, diplopia, and periorbital edema tend to resolve. Persistent ocular complications are more frequent after treating intraconal lesions. Enophthalmus may occur in patients with associated ventriculo-peritoneal shunt. According to patient's satisfaction, fairly acceptable results are attained.

Endoscopic transorbital approach bone pillars: a comprehensive stepwise anatomical appraisal.

OBJECTIVE: The endoscopic superior eyelid transorbital approach has garnered significant consideration and gained popularity in recent years. Detailed anatomical knowledge along with clinical experience has allowed refinement of the technique as well as expansion of its indications. Using bone as a consistent reference, the authors identified five main bone pillars that offer access to the different intracranial targeted areas for different pathologies of the skull base, with the aim of enhancing the understanding of the intracranial areas accessible through this corridor. METHODS: The authors present a bone-oriented review of the anatomy of the transorbital approach in which they conducted a 3D analysis using Brainlab software and performed dry skull and subsequent cadaveric dissections. RESULTS: Five bone pillars of the transorbital approach were identified: the lesser sphenoid wing, the sagittal crest (medial aspect of the greater sphenoid wing), the anterior clinoid, the middle cranial fossa, and the petrous apex. The associations of these bone targets with their respective intracranial areas are reported in detail. CONCLUSIONS: Identification of consistent bone references after the skin incision has been made and the working space is determined allows a comprehensive understanding of the anatomy of the approach in order to safely and effectively perform transorbital endoscopic surgery in the skull base.

"Boot-on-Donut" procedure for anterior and large septal perforation.

BACKGROUND: Surgical closure of large nasoseptal perforation (NSP) is challenging. The use of an extended anterior ethmoidal artery (eAEA) flap to reconstruct NSP may present with difficulties for NSPs which have their upper edge in a high position. METHOD: We propose adding a "donut-shape" flap from surrounding septal tissue to the eAEA flap. Thus, the inverted edges of this flap allow to cover the uppermost aspect of the NSP. A series of 18 patients with complete closure of NSPs was included. CONCLUSION: This novel "Boot-on-Donut" technique consisting of the eAEA flap (Boot) and inverted edges (Donut) is a feasible procedure that allows to reconstruct large NSP located superiorly.

Assessing the effect of absorbable steroid sinus implant: a state-of-the-art systematic review.

OBJECTIVES: Endoscopic sinus surgery is not a definitive treatment for chronic rhinosinusitis (CRS). The use of sinus stents after surgery to maintain sinus patency and deliver local steroids has gained popularity. The first steroid-eluting bioabsorbable implant (SEBI) approved for this indication, later Propel, was developed in 2011. This state-of-the-art review aims to summarize the available evidence, as well as to point out potential pitfalls and lack of specific analyses to guide future research on this new therapeutic option. DATA SOURCES: Pubmed (Medline), the Cochrane Library, EMBASE, SciELO. REVIEW METHODS: Nine research questions were defined: Are steroid-eluting Sinus implants useful for the control of CRS symptoms after surgery? Do they improve surgical field healing after CRS surgery? Do they decrease polyp regrowth after ESS? Do they decrease the need for ESS? Are they useful in symptom control as in-office procedure? Are they better than other steroid-impregnated resorbable materials? Do they have a positive impact on olfaction? Are they safe? Are they cost-effective? Retrieved articles were reviewed by two authors. RESULTS: Twenty nine studies were included: 3 metanalysis, 1 systematic review, 10 randomized clinical trials, 4 quasi-experimental studies, 1 retrospective cohort study, 4 cost studies, 3 case series and 2 expert consensus. The review encompassed a population of 3,012 patients treated with SEBI and 2826 controls. CONCLUSIONS: This is the first state-of-the-art review assessing steroid eluting bioabsorbable stent evidence. Despite the effort in recent years, still several questions remain unanswered. This review will hopefully guide future research efforts to better define the role of SEBI in the otolaryngology practice.

Management of patients with chronic rhinosinusitis with nasal polyps in Spain: learnings from a nationwide survey of otorhinolaryngologists.

PURPOSE: To describe the self-reported practices on the diagnosis, treatment, and follow-up of patients with chronic rhinosinusitis with nasal polyps (CRSwNP) by ear, nose, and throat (ENT) specialists in Spain to identify potential areas for management optimization. METHODS: A cross-sectional online survey with 16 questions was carried out. Recruitment was performed by emailing registered ENT specialists in the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC). RESULTS: In total, 127 ENT specialists completed the survey. Fifty-one percent of respondents combined clinical criteria and objective evidence of mucosal inflammation to diagnose CRSwNP. Patient interview and, to a lower degree, a visual analogue scale were the most employed diagnostic tools to quantify symptom severity. Less than half (45%) routinely used the 22-item sino-nasal outcomes test (SNOT-22) to assess the impact of CRSwNP disease in quality of life. The use of patient-reported outcomes and other clinical evaluation tools showed a larger uptake among ENT specialists that worked at an ENT department with an available rhinology unit. Almost all the specialists surveyed (95%) recommended biological treatment, particularly in patients with uncontrolled CRSwNP with respiratory comorbidities (76%), as well as in candidates for revision surgery (66%). CONCLUSION: Spanish otorhinolaryngologists showed a trend toward incorporating CRSwNP guideline recommendations in their clinical practice. The observed low uptake of patient-reported outcomes and objective clinical evaluation tools in routine clinical practise have been identified as areas for optimizing the management of patients with CRSwNP.

International clinical assessment of smell: An international, cross-sectional survey of current practice in the assessment of olfaction.

OBJECTIVES: Olfactory dysfunction (OD) is common and carries significant personal and societal burden. Accurate assessment is necessary for good clinical and research practice but is highly dependent on the assessment technique used. Current practice with regards to UK/international clinical assessment is unknown. We aimed to capture current clinical practice, with reference to contemporaneously available guidelines. We further aimed to compare UK to international practice. DESIGN: Anonymous online questionnaire with cross-sectional non-probability sampling. Subgroup analysis according to subspeciality training in rhinology ('rhinologists' and 'non-rhinologists') was performed, with geographical comparisons only made according to subgroup. PARTICIPANTS: ENT surgeons who assess olfaction. RESULTS: Responses were received from 465 clinicians (217 from UK and 17 countries total). Country-specific response rate varied, with the lowest rate being obtained from Japan (1.4%) and highest from Greece (72.5%). Most UK clinicians do not perform psychophysical smell testing during any of the presented clinical scenarios-though rhinologists did so more often than non-rhinologists. The most frequent barriers to testing related to service provision (e.g., time/funding limitations). Whilst there was variability in practice, in general, international respondents performed psychophysical testing more frequently than those from the UK. Approximately 3/4 of all respondents said they would like to receive training in psychophysical smell testing. Patient reported outcome measures were infrequently used in the UK/internationally. More UK respondents performed diagnostic MRI scanning than international respondents. CONCLUSIONS: To our knowledge, this is the most comprehensive UK-based, and only international survey of clinical practice in the assessment of OD. We present recommendations to improve practice, including increased education and funding for psychophysical smell testing. We hope this will promote accurate and reliable olfactory assessment, as is the accepted standard in other sensory systems.

European Academy of Allergy and Clinical Immunology position paper on endoscopic scoring of nasal polyposis.

Nasal endoscopy is not only used for the diagnosis of chronic rhinosinusitis with nasal polyps (CRSwNP), but also for monitoring the response to therapy playing an important role in both daily practice and research. In contrast to patient-reported outcomes, endoscopic nasal polyp scoring by independent blinded readers is an objective measurement, not influenced by the placebo effect. It is safer and cheaper compared with computed tomography imaging and therefore, better suited for regular assessments of the extent of the disease. Since the early 90s, a variety of endoscopic staging methods have been proposed and used in clinical research, making it hard to compare results from different studies. This paper resulted from a task force with experts in the field of CRSwNP, originated by the Ear, Nose and Throat section of the European Academy of Allergy and Clinical Immunology and aims to provide a unified endoscopic NP scoring system that can serve as a reference standard for researchers, but also as a useful tool for practitioners involved in the management of CRSwNP.

Pheno-Endotyping Antrochoanal Nasal Polyposis.

PURPOSE OF REVIEW: Antrochoanal polyps (ACPs) are benign polypoid lesions arising from the inner wall of the maxillary sinus and extending into the choana. Although the diagnosis and treatment strategies of ACP have changed since this entity was first described, the underlying pathogenic mechanism of APC is poorly understood. This article reviews the current knowledge of the etiology, inflammatory parameters, and microscopic findings of ACP. RECENT FINDINGS: The inflammatory pattern of ACP appears to center around a neutrophilic inflammation T1-dominant endotype. Apart from the inflammatory component of ACP, at the microscopic level, the presence of tissue remodeling, mostly fibrin deposition and edema, and cysts in the epithelium and lamina propria has been described. Although the origin of this T1-dominant endotype immune response of ACPs is not entirely clear, it could be related to a lymphatic obstruction mechanism. This review serves to define a phenotype of ACP with potential endotypes based on the characteristics of the inflammatory parameters, microscopic findings, and hypotheses about the pathogenesis of ACP.

Olfactory Dysfunction in Mental Illness.

PURPOSE OF REVIEW: Olfactory dysfunction contributes to the psychopathology of mental illness. In this review, we describe the neurobiology of olfaction, and the most common olfactory alterations in several mental illnesses. We also highlight the role, hitherto underestimated, that the olfactory pathways play in the regulation of higher brain functions and its involvement in the pathophysiology of psychiatric disorders, as well as the effect of inflammation on neurogenesis as a possible mechanism involved in olfactory dysfunction in psychiatric conditions. RECENT FINDINGS: The olfactory deficits present in anxiety, depression, schizophrenia or bipolar disorder consist of specific alterations of different components of the sense of smell, mainly the identification of odours, as well as the qualifications of their hedonic valence (pleasant or unpleasant). Epidemiological findings have shown that both environmental factors, such as air pollutants, and inflammatory disease of the upper respiratory tract, can contribute to an increased risk of mental illness, at least in part, due to peripheral inflammatory mechanisms of the olfactory system. In this review, we describe the neurobiology of olfaction, and the most common olfactory function alterations in several psychiatric conditions and its role as a useful symptom for the differential diagnosis. We also highlight the effect of inflammation on neurogenesis as a possible mechanism involved in olfactory dysfunction in these psychiatric conditions.

Pathophysiological Link Between Chronic Rhinosinusitis and Ear Disease.

PURPOSE OF REVIEW: In the clinical practice, patients affected by chronic rhinosinusitis (CRS) commonly complain of otologic symptoms. This review aims to describe the available literature evidence assessing the relationship between CRS and ear illnesses published in the last 5 years. RECENT FINDINGS: Available evidence suggests a higher prevalence of otologic symptoms in patients suffering from CRS, affecting up to 87% of patients. These symptoms may be related to Eustachian tube dysfunction, which improves after treatment for CRS. A few studies suggested a potential but not confirmed role of CRS in cholesteatoma, chronic otitis media, and sensorineural hypoacusis. A special type of otitis media with effusion (OME) may occur in patients with CRS, which seems to respond well to new biologic therapy. Ear symptoms appear to be highly prevalent in patients with CRS. So far, the available evidence is robust only for Eustachian tube dysfunction, which has been shown to be particularly impaired in CRS patients. Additionally, the Eustachian tube function appears to improve after treatment for CRS. Finally, interesting preliminary data were described for eosinophilic otitis media, as it appears to respond well to the treatment with biologics.

Management of Mechanical Nasal Obstruction Isolated or Associated to Upper Airway Inflammatory Diseases in Real Life: Use of both Subjective and Objective Criteria.

PURPOSE OF REVIEW: Mechanical nasal obstruction (MNO) is a prevalent condition with a high impact on patient's quality-of-life (QoL) and socio-economic burden. The aim of this study was to determine the usefulness of both subjective and objective criteria in the appropriate management of MNO, either alone or associated to upper airway inflammatory diseases such as allergic rhinitis (AR) or chronic rhinosinusitis with nasal polyps (CRSwNP). RECENT FINDINGS: A long debate persists about the usefulness of subjective and objective methods for making decisions on the management of patients with nasal obstruction. Establishing standards and ranges of symptom scales and questionnaires is essential to measure the success of an intervention and its impact on QoL. To our knowledge this is the first real-life study to describe the management of MNO using both subjective and objective criteria in MNO isolated or associated to upper airway inflammatory diseases (AR or CRSwNP). Medical treatment (intranasal corticosteroids) has a minor but significant improvement in MNO subjective outcomes (NO, NOSE, and CQ7) with no changes in loss of smell and objective outcomes. After surgery, all MNO patients reported a significant improvement in both subjective and objective outcomes, this improvement being higher in CRSwNP. We concluded that in daily clinical practice, the therapeutic recommendation for MNO should be based on both subjective and objective outcomes, nasal corrective surgery being the treatment of choice in MNO, either isolated or associated to upper airway inflammatory diseases, AR or CRSwNP.

Effects of Endoscopic Sinus Surgery on Olfactory Function.

PURPOSE OF REVIEW: To review the effects of endoscopic sinus surgery and endonasal approaches to the skull base on olfaction. RECENT FINDINGS: Advancements in endonasal endoscopic approaches to the sinuses and skull base allow for direct treatment of a variety of sinonasal and skull base diseases. However, these extended approaches will often require manipulation of normal anatomical structures and the olfactory neuroepithelium. Depending on the planned procedure and extent of disease, the prognosis of olfactory perception can vary significantly among patients. Endoscopic sinonasal surgical procedures may impact olfaction. Optimizing olfactory function requires proper surgical techniques, gentle handling of tissue, and perioperative care. Surgeons must discuss objectives and manage patient expectations. Routine olfactory assessment is crucial in surgical work-up and follow-up. Preserving anatomical structures while addressing the obstruction of the olfactory cleft helps to prevent decreased olfactory threshold. However, smell identification and discrimination do not always correlate with sinonasal anatomy.

Therapeutic management of allergic rhinitis: a survey of otolaryngology and allergology specialists.

PURPOSE: To describe the current management of allergic rhinitis (AR) in Spain's specialized care according to the next-generation ARIA guidelines. METHODS: An ad hoc online survey was distributed to AR specialists to appraise their perceptions of pathology management, knowledge of next-generation ARIA guidelines (including four case clinics), and their views on the principal barriers and the actions to proper AR management. RESULTS: one hundred nine specialists (38.5% allergists and 61.5% otolaryngologists) completed the study survey. Most respondents (87.2%) had read all or part of the Next-Generation ARIA Guidelines, and 81.6% stated that they considered the patient's treatment choice preferences. However, only 20.2% of specialists answered according to the recommendations in at least three of the four case clinics. Most participants failed to fulfill the treatment duration according to the guidelines. They regarded the lack of multidisciplinary teams (21.7%) and the lack of patients' AR treatment adherence (30.6%) as the most critical healthcare system- and patient-related barriers to the correct management of AR, respectively. Promoting patients' education was considered the most crucial action to improve it. CONCLUSION: Despite specialists' awareness, there is a gap between the evidence-based guidelines' recommendations and their implementation in clinical practice.

Chronic rhinosinusitis with nasal polyps management in the biologic therapy era: an international YO-IFOS survey.

PURPOSE: To investigate the consistency between the international guidelines recommendations and worldwide standard practices regarding diagnostic work-up and follow-up strategies for managing patients with Chronic Rhinosinusitis with Nasal Polyps (CRSwNP) in the era of monoclonal antibodies. METHODS: A questionnaire developed by the Rhinology section of the Young Otolaryngologists of the International Federation of Oto-rhino-laryngological Societies (Yo-IFOS) included items regarding the management of CRSwNP patients, monoclonal prescription, surgical and follow-up procedures, awareness of biologicals availability, and other relevant clinical practices. The online survey was directed to otolaryngologists and distributed in Europe, North America, South America, and the Middle East through otolaryngological and/or rhinological societies. RESULTS: A total of 202 responses were analyzed; the mean participants' age was 45 ± 11 (73% men and 27% women), and 31% were from the United States, Canada 19%, Europe 45%, Middle East and South America 5%. Only 60% of the respondents declared using validated symptoms and endoscopic score systems in their clinical practice. Several practice discrepancies emerged in our cohort, including preferred surgical approach, prescription of preoperative oral steroids, and perioperative antibiotics (59% and 58%, respectively), as well as divergent awareness levels of available biologics for CRSwNP worldwide. CONCLUSIONS: CRSwNP needs a complex and time-consuming assessment, according to the latest guidelines. There seems to be a gap between these recommendations and the real-world data, which should draw more attention to bringing them into uniform clinical practice in the near future.

Olfactory Bulb Excitotoxicity as a Gap-Filling Mechanism Underlying the Link Between Traumatic Brain Injury-Induced Secondary Neuronal Degeneration and Parkinson's Disease-Like Pathology.

There is increasing preclinical and clinical data supporting a potential association between Traumatic Brain Injury (TBI) and Parkinson's disease (PD). It has been suggested that the glutamate-induced excitotoxicity underlying TBI secondary neuronal degeneration (SND) might be associated with further development of PD. Interestingly, an accumulation of extracellular glutamate and olfactory dysfunction are both sharing pathological conditions in TBI and PD. The possible involvement of glutamate excitotoxicity in olfactory dysfunction has been recently described, however, the role of olfactory bulbs (OB) glutamate excitotoxicity as a possible mechanism involved in the association between TBI and PD-related neurodegeneration has not been investigated yet. We examined the number of nigral dopaminergic neurons (TH +), nigral α-synuclein expression, the striatal dopamine transporter (DAT) expression, and motor performance after bilateral OB N-Methyl-D-Aspartate (NMDA)-induced excitotoxic lesions in rodents. Bulbar NMDA administration induced a decrease in the number of correct choices in the discrimination tests one week after lesions (p < 0.01) and a significant decrease in the number of nigral DAergic neurons (p < 0.01) associated with an increase in α-synuclein expression (p < 0.01). No significant striatal changes in DAT expression or motor alterations were observed. Our results show an association between TBI-induced SND and PD-related neurodegeneration suggesting that the OB excitotoxicity occurring in TBI SND may be a filling gap mechanism underlying the link between TBI and PD-like pathology.

Endoscopic superior eyelid transorbital approach: how I do it.

BACKGROUND: The endoscopic transorbital approach to the skull base is currently growing in popularity, and it is nowadays progressively used as a skull base approach. Clinical experience, along with detailed anatomical knowledge, makes this technique safe and effective. METHOD: We present a step by step description of our technique based on the most recent anatomic references, and clinical experience. In order to better understand every phase of the procedure, we propose to keep on the following scheme, that is (1) skin phase; (2) working space; (3) lesion removal; (4) reconstruction. Hence, alone or in combination with the well-known endonasal pathway, the transorbital avenue seems to be a useful approach for selected skull base lesions. We present our technique, along with an anatomic analysis on cadaveric specimens. CONCLUSIONS: Detailed knowledge of surgical anatomy, and a specific stepwise analysis of each part of the surgical procedure, is notably useful in order to safely and effectively perform a superior eyelid endoscopic transorbital surgery to the skull base.