Nasal Cavity Research Articles

Combined Endonasal and Transseptal Approach to Achieve Binostril Access in Endoscopic Skull Base Approaches to Minimize Nasal Morbidity: A Technical Note

IntroductionOver the years, feasibility & safety of EEAs has become well established & the focus has now shifted to minimising the nasal morbidity. To this end, several modifications in nasal stage have been described that have focussed primarily on preservation of nasal mucosa on right side of nasal cavity (NC). However, the issue of nasal mucosal preservation on left side of NC has largely been ignored. In this paper, the author describes a modified technique that can eliminate mucosal damage in left NC. MethodIn modified technique, trans-septal approach is utilised on left & endonasal on right side. A hemitransfixion incision is used to raise left submucosal tunnel. The mucosa of tunnel lies laterally in apposition with lateral nasal wall, thereby protecting it from injury by repeated passage of instruments. When tunnel mucosa is pushed back medially, left NC appears absolutely normal without any evidence of mucosal damage. ResultsCombined endonasal & trans-septal technique for nasal stage was performed in 51 patients with sellar/suprasellar lesions. Nonfunctional pituitary adenomas were the most common pathology (macroadenomas-n=14; Giant adenomas-n=10) followed by functional adenomas (acromegaly-n=10; prolactinomas- n=3; Cushings’s disease- n=1), craniopharyngiomas (n=6), clival tumours (n=5), & tuberculum sella meningiomas (n=2). ConclusionsA combination of endonasal and trans-septal approaches utilises the advantages of both endoscopic & microscopic approaches sans the disadvantage of restricted space seen in microscopic approaches. It makes binostril approach least disruptive to left nasal mucosa & thus can reduce overall morbidity of EEAs.

Experimental and numerical investigation of pressure distribution in human upper airway passage before and after maxillary sinus surgery

Sinusitis, a common disease of the maxillary sinus, is initially managed with saline solution and medication, resulting in the resolution of symptoms within a few days in most cases. However, Functional Endoscopic Sinus Surgeries are recommended if pharmacological treatments prove ineffective. This research aims to investigate the effects of maxillary sinus surgery on the airflow field, pressure distribution within the nasal cavity, and overall ventilation. This study utilized a three-dimensional realistic nasal cavity model constructed from CT images of a healthy adult. Virtual surgery including uncinectomy with Middle Meatal Antrostomy, two standard procedures performed during such surgeries, was performed on the model under the supervision of a clinical specialist. Two replicas representing pre- and post-operative cases were created using 3D printing for experimental purposes. Various breathing rates ranging from 3.8 to 42.6 L/min were examined through experimental and numerical simulations. To ensure the accuracy of the numerical simulations, the results were compared to measured pressure data, showing a reasonable agreement between the two. The findings demonstrate that uncinectomy and Middle Meatal Antrostomy significantly enhance the ventilation of the maxillary sinuses. Furthermore, increasing inspiratory rates leads to further improvements in ventilation. The static pressure distribution within the maxillary sinuses remains relatively uniform, except in regions close to the sinus ostium, even after surgical intervention.

The human microbiome in space: parallels between Earth-based dysbiosis, implications for long-duration spaceflight, and possible mitigation strategies.

SUMMARYThe human microbiota encompasses the diverse communities of microorganisms that reside in, on, and around various parts of the human body, such as the skin, nasal passages, and gastrointestinal tract. Although research is ongoing, it is well established that the microbiota exert a substantial influence on the body through the production and modification of metabolites and small molecules. Disruptions in the composition of the microbiota-dysbiosis-have also been linked to various negative health outcomes. As humans embark upon longer-duration space missions, it is important to understand how the conditions of space travel impact the microbiota and, consequently, astronaut health. This article will first characterize the main taxa of the human gut microbiota and their associated metabolites, before discussing potential dysbiosis and negative health consequences. It will also detail the microbial changes observed in astronauts during spaceflight, focusing on gut microbiota composition and pathogenic virulence and survival. Analysis will then turn to how astronaut health may be protected from adverse microbial changes via diet, exercise, and antibiotics before concluding with a discussion of the microbiota of spacecraft and microbial culturing methods in space. The implications of this review are critical, particularly with NASA's ongoing implementation of the Moon to Mars Architecture, which will include weeks or months of living in space and new habitats.

A New Method for Obtaining Monospecies and Binary Cultures of Staphylococcus spp. in Alginate Gel and the Study of the Action of Active Compounds on These Cultures on the Example of Catecholamines.

A simple and efficient method for obtaining monospecies and binary Staphylococcus aureus and Staphylococcus epidermidis cultures in sodium alginate gel matrix mimicking the natural microenvironment of the nasal cavity was proposed. The cultures were used for studying the effect of norepinephrine on monospecies and binary communities of two types of bacteria, S. aureus (invasive strain) and S. epidermis (commensal strain). After 24-h incubation, S. aureus predominated in the binary community, but later it was replaced by S. epidermis. Norepinephrine at higher concentrations accelerated this process without principally changing it. The model can be used to develop more effective complex antimicrobial drugs.

Astodrimer sodium nasal spray forms a barrier to SARS-CoV-2 in vitro and preserves normal mucociliary function in human nasal epithelium

COVID-19 remains a severe condition for many including immunocompromised individuals. There remains a need for effective measures against this and other respiratory infections, which transmit via virus-laden droplets that reach the nasal or oral mucosae. Nasal sprays offer potential protection against viruses. Such formulations should preserve normal nasal mucociliary function. The antiviral barrier efficacy and effects on mucociliary function of astodrimer sodium nasal spray (AS-NS) were evaluated and compared with other available nasal sprays—low pH hydroxypropyl methylcellulose (HPMC-NS), iota-carrageenan (Carr-NS), nitric oxide (NO-NS), and povidone iodine (PI-NS). Assays simulated clinical conditions. Antiviral barrier function and cell viability were assessed in airway cell monolayers, while a model of fully differentiated human nasal epithelium (MucilAir™) was utilized to evaluate tissue integrity, cytotoxicity, cilia beating frequency, and mucociliary clearance. AS-NS reduced infectious virus in cell monolayers and demonstrated a benign cytotoxicity profile. In human nasal epithelium ex vivo, AS-NS had no impact on mucociliary function (cilia beating nor mucociliary clearance). Carr-NS, HPMC-NS, NO-NS and PI-NS demonstrated limited antiviral effects, while HPMC-NS caused inhibition of mucociliary function. Astodrimer sodium nasal spray demonstrates an acceptable nonclinical efficacy and safety profile as a barrier nasal spray against respiratory viral infection in the nasal cavity.

Research on multi-sequence MR image synthesis CT algorithm based on unsupervised method

BackgroundUsing multi-sequence MRI to synthesize CT, combining different MRI sequences, and processing synthetic CT (sCT) based on unsupervised algorithms, to conduct more in-depth and comprehensive research on MR-based radiotherapy planning. MethodsFirst, we compare and analyze the effects of single-sequence MRI synthesis to CT to determine the quality of the synthesis and find a set of optimal sequence combinations. In addition, the study introduces a Staged Multi-Sequence Fusion Network (SMSF-Net) that employs an unsupervised approach to effectively fuse information from multiple MRI sequences. The staged sequence fusion module can efficiently extract information from different sequences and combine complementary information from different sequences. Finally, image encoding is processed using a multi-layer convolutional network to generate synthetic CT images. ResultsIn this study, the mean absolute error (MAE), root mean square error (RMSE), peak signal-to-noise ratio (PSNR), and structural similarity (SSIM) of the SMSF-Net are 18.85, 84.62, 34.31, and 0.962, which are superior to other single-sequence models and multi-sequence models. Experiments show that the improvement of SMSF-Net is statistically significant. In the qualitative comparison experiment, sCT synthesized by SMSF-Net is superior to other models in detail in the synthesis of complex areas of bones and nasal cavities. ConclusionThis study proposes a Staged SMSF-Net. As a multi-sequence MRI synthesis sCT algorithm based on unsupervised learning, SMSF-Net can use the complementary information between multiple sequences to improve the quality of synthetic sCT. This study has reference value for MRI-only radiotherapy planning.

Twistable and Stretchable Nasal Patch for Monitoring Sleep-Related Breathing Disorders Based on a Stacking Ensemble Learning Model.

Obstructive sleep apnea syndrome disrupts sleep, destroys the homeostasis of biological systems such as metabolism and the immune system, and reduces learning ability and memory. The existing polysomnography used to measure sleep disorders is executed in an unfamiliar environment, which may result in sleep patterns that are different from usual, reducing accuracy. This study reports a machine learning-based personalized twistable patch system that can simply measure obstructive sleep apnea syndrome in daily life. The stretchable patch attaches directly to the nose in an integrated form factor, detecting sleep-disordered breathing by simultaneously sensing microscopic vibrations and airflow in the nasal cavity and paranasal sinuses. The highly sensitive multichannel patch, which can detect airflow at the level of 0.1 m/s, has flexibility via a unique slit pattern and fabric layer. It has linearity with an R2 of 0.992 in the case of the amount of change according to its curvature. The stacking ensemble learning model predicted the degree of sleep-disordered breathing with an accuracy of 92.9%. The approach demonstrates high sleep disorder detection capacity and proactive visual notification. It is expected to help as a diagnostic platform for the early detection of chronic diseases such as cerebrovascular disease and diabetes.

Effects of sitting, supine, and prone postures on nasal patency in individuals with obstructive sleep apnea syndrome

BackgroundStudies have found that in healthy individuals without nasal disease, changes in posture cause an increase in nasal resistance, especially in the prone posture. Many patients with obstructive sleep apnea syndrome (OSAS) sleep in a prone posture, but no studies have examined the effect of this change in posture on nasal resistance in patients with OSAS. Therefore, we conducted this study to investigate this posture-related physical phenomenon in individuals with OSAS.MethodsWe evaluated the nasal patency of 29 patients diagnosed with OSAS using the visual analog scale (VAS), acoustic rhinometry, and video-endoscopy in the sitting, supine, and prone postures.ResultsIn the OSAS group, both supine and prone postures significantly influenced subjective nasal blockage and led to a notable reduction in the minimal cross-sectional area (mCSA) as determined by acoustic rhinometry, compared to the sitting posture. The prone posture exhibited a more pronounced effect than the supine posture. Endoscopic evaluations further revealed increased hypertrophy of the inferior turbinate in the supine posture for the right nasal passage and the prone posture for the left. However, no significant differences were observed between the prone and supine postures.ConclusionIn OSAS patients, nasal resistance significantly increased in supine and prone postures compared to sitting, with the prone posture showing a greater effect. Clinicians should consider a patient’s habitual sleep posture and the effects of postural changes when assessing OSAS severity and devising treatment plans.Level of Evidence4.

Virulence and tissue tropism of different epidemiologically significant SARS-CoV-2 variants for golden Syrian hamsters

Introduction. Animal models for SARS-CoV-2 infection, reproducing the clinical features of COVID-19 in humans, are important tools for studying the pathogenesis of the disease, transmission of the pathogen and are indispensable for testing antiviral drugs and vaccines. The aim of the study was to assess the virulence and tissue tropism for golden Syrian hamsters of SARS-CoV-2 strains belonging to different epidemiologically significant variants: Wuhan-like, Delta, Omicron BA.1.1 and Omicron BA.5.2. Materials and methods. Hamsters were intranasally infected with different SARS-CoV-2 strains. Virulence and tissue tropism of SARS-CoV-2 strains were assessed by comparing the dynamics of weight, viral load in organs and histopathological changes in lungs in infected and uninfected animals. Results. The Wuhan-like Dubrovka strain had the greatest virulence for hamsters, which was manifested by the development of severe pneumonia and a delay in weight gain by 14.6%, high virus content in the lungs, nasal passages and brain — 6.2, 5,9 and 3.7 lg TCID50/ml of homogenate, respectively. Presumably, it was the infection of the Wuhan-like virus of the central nervous system that negatively affected the weight and general condition of the animals. When hamsters were infected with viruses belonging to the Delta and Omicron variants, the observed minor weight loss in animals was uninformative, so indicators such as lung histopathology, viral load in the lungs, nasal passages, heart and other organs played a decisive role in assessing the virus pathogenicity. A score assessment of lung histopathology was of particular value in assessing the severity of pneumonia, since it reduced subjectivity in evaluating the results of histological examination and provided a semi-quantitative assessment of the pathological process. Conclusion. Despite the revealed lower virulence for hamsters of viruses belonging to the Delta and Omicron variants compared to the ancestral Wuhan virus, this animal model for COVID-19 retains its value for conducting preclinical trials of antiviral drugs.

The nasal cavity of the bearded seal: An effective and robust organ for retaining body heat and water

We report the effects of varying physiological and other properties on the heat and water exchange in the maxilloturbinate structure (MT) of the bearded seal (Erignathus barbatus or Eb) in realistic environments, using a computational fluid dynamics (CFD) model. We find that the water retention in percent is very high (about 90 %) and relatively unaffected by either cold (−30 °C) or warm (10 °C) conditions. The retention of heat is also high, around 80 % . Based on a consideration of entropy production by the maxilloturbinate system, we show that anatomical and physiological properties of the seal provide good conditions for heat and water exchange at the mucus lining in the seal’s nasal cavity. At normal values of tidal volume and maxilloturbinate (MT) length, the air temperature in the MT reaches the body temperature before the air has left the MT channels. This confers a safety factor which is expected to be helpful in exercise, when ventilation increases.

The impact of hydroxybutyl chitosan and 5-fluorouracil on the procedure of endoscopic endonasal dacryocystorhinostomy.

To investigate the effects of hydroxybutyl chitosan (HBCS) with and without 5-fluorouracil (5-FU) during endoscopic endonasal dacryocystorhinostomy (Endo-DCR). In addition, the present study observed the impact of HBCS and 5-FU on the functions of the nasal mucosal cell population in vivo. Patients were randomized into HBCS (group A), HBCS combined with 5-FU (group B), and gelatin sponge control group (group C). 16S rRNA high-throughput sequencing technology examined the conjunctival sac and nasal flora changes. In addition, CCK8, cell scratching, and flow cytometry were used to investigate the effects of HBCS and 5-FU on the nasal mucosal cell populations. Subjects in groups A, B, and C had anastomotic areas of 21.83 ± 12.69 mm2, 21.57 ± 14.53 mm2, and 12.45 ± 8.16 mm2, respectively (P = 0.0359). Group A had less severe epiphora than the other two groups at 1-, 2-, and 12-week postoperative follow-up (P < 0.05). Complications around the anastomosis in group A were the least severe of the three groups (P = 0.0259). After surgery, the proportion of pathogenic bacteria in the conjunctival sac and nasal cavity was higher in groups A and B than in healthy adults. At the 2-week follow-up, the structure of nasal flora in group A was more similar to that of the healthy adults compared to group B. Intraoperative use of HBCS at the anastomose improves the postoperative outcome of En-DCR. 5-FU cannot give better postoperative results in En-DCR and is detrimental to the normalization of the postoperative flora in patients with chronic dacryocystitis. At the cellular level, both HBCS and 5-FU inhibit the migration of nasal mucosal cell populations, and 5-FU inhibits proliferation but does not promote apoptosis.

Development and initial evaluation of a rigid rhinoscopy model as a pedagogic tool in veterinary medicine.

No model exists to train the handling skills required for successful performance of rigid rhinoscopy in veterinary patients. The complex anatomy of the nasal cavity, the limited space between turbinates, and the propensity of the mucosa to bleed with slight trauma make thorough examination of a nasal cavity difficult. The goal of this study was development and initial testing of a low fidelity canine rigid rhinoscopy training model for veterinary novices. A model comprising three tubes of various lumen diameters that were connected to a conduction system was created. Each tube contained three colored stars and a number that were to be described by trainees. The model both counted contacts and audibly beeped if pressure was applied by the rhinoscope to the sides of the tube. Board-certified veterinary internists (experts) and veterinary students (novices) performed two timed simulation exercises during a single session. Participants completed a questionnaire before and after the simulations to assess model utility. There were no statistically significant differences in contacts or time to completion between novices and experts. Novices provided feedback that the model improved their ability to control the rhinoscope, helped them learn to perform rigid rhinoscopy, was enjoyable, and was appropriately challenging. Expert feedback included that the model was a potentially useful pedagogic tool for training rigid rhinoscopy, including hand control and indirect hand-eye coordination, and was appropriately challenging. We conclude that this rhinoscopy model has potential to be an effective teaching tool for novice rhinoscopists. With minor modifications, the model could provide additional challenges.

Traumatic encephalocele in the nasal cavity after 6 years of trauma: a case report

BackgroundEncephalocele refers to protrusion of the meninges and brain tissue through a skull bone defect. It results from congenital, traumatic, neoplastic, or spontaneous reasons. Traumatic encephalocele occurs because of the posttraumatic fracture of the skull bone or iatrogenic causes. The manifestations vary a lot, such as rhinorrhea, seizures, headaches, and focal neurological deficits.Case presentationA 20-year-old Syrian male presented to our department with the complaint of clear cerebrospinal fluid drainage from his right nostril, which started 6 years ago after a head trauma, moderate headache, and episodes of tonic–clonic seizures without any response to medical treatment. Then, 2 months ago, the patient had meningoencephalitis, so he was admitted to the intensive care unit and treated for a month until he was cured. The patient underwent radiological investigations, which showed that he had a base fracture with an encephalocele in the nasal cavity. The brain tissues with the meninges herniated through the skull base fracture with a significant expansion of the subarachnoid spaces in the right hemisphere. He was advised to undergo surgical repair at that time, but he refused the surgery. During this visit, surgery was indicated. The surgery was done by a specialist who returned the herniated brain tissues to their normal location, repaired the meninges, and reconstructed the skull base with bone cement and bio-glue. The patient’s recovery after the surgery was uneventful.ConclusionTraumatic encephalocele is a rare and unexpected complication of trauma, but we should keep it in mind when the patient comes with head trauma because of its life-threatening consequences. This complication can happen after years of trauma if the patient refuses treatment, therefore, we must educate patients about the dangerous results of neglecting cerebrospinal fluid leakage and skull fractures.

Angiomyolipomatous Lesions of the Nasal Cavity (Sinonasal Angioleiomyoma with Adipocytic Differentiation): A Multi-Institutional Immunohistochemical and Molecular Study.

Mesenchymal neoplasms composed of vascular, smooth muscle, and adipocytic components are uncommon in the nasal cavity. While angioleiomyoma (AL) is a smooth muscle tumor in the Head & Neck WHO classification, it is considered of pericytic origin in the Skin as well as Soft Tissue and Bone classifications. For nasal AL with an adipocytic component, the terms AL with adipocytic differentiation and angiomyolipoma (AML) have been applied, among others. AML is a type of perivascular epithelioid cell tumor (PEComa), most often arising in the kidney, sometimes associated with the tuberous sclerosis complex (TSC). It is uncertain whether nasal cavity AML and AL are best considered hamartomas or neoplasms, as their genetics are largely unexplored. We performed a multi-institutional retrospective study of nasal cavity mesenchymal lesions. Patient demographics, clinical histories, and histologic and immunohistochemical findings were collected. DNA and RNA were extracted from formalin-fixed, paraffin-embedded tissue and analyzed by SNP-based chromosomal microarray, targeted RNA fusion sequencing, and whole-exome sequencing. Fifteen lesions (3 to 42 mm) were identified predominantly in male (87%) patients with a median age of 60. Patients typically presented with obstructive symptoms, and none had a history of TSC. One AL was a recurrence from six years prior; 11 cases showed no recurrence (median 4.7 years, range: 0.88-12.4). Morphologically, 11 AMLs contained 30-80% smooth muscle, 10-25% vasculature, and 2-60% adipose tissue, while four ALs contained 70-80% smooth muscle and 20-30% vasculature. Other histologic observations included surface ulceration, vascular thrombosis, chronic inflammation, and myxoid change; no well-developed epithelioid cell morphology was identified. Immunohistochemically, all cases were positive for smooth muscle markers (actin and/or desmin) and negative for melanocytic markers. Molecular analysis revealed loss of 3p and 11q in a single AML. No other known pathogenic copy number or molecular alterations were seen, including in TSC1/2, TFE3, or NOTCH2. Nasal cavity AML lacks morphologic, immunophenotypic, and genetic features of PEComa family AMLs. The significant histologic overlap between nasal AML and AL without distinguishing molecular features in either entity suggests "sinonasal angioleiomyoma with adipocytic differentiation" may be the most appropriate terminology for hybrid vascular and smooth muscle lesions containing adipocytic components.

Characterization of Oxacillin-Resistant and Oxacillin-Susceptible mecA-Positive Staphylococcus pseudintermedius from Skin Lesions and Nasal Cavities of Dogs with Clinical Pyoderma.

Understanding the epidemiology of mecA-positive Staphylococcus pseudintermedius strains, including those that are oxacillin-susceptible but potentially inducible to resistance, is crucial for developing effective treatment strategies and mitigating public health risks. This study characterized 87 mecA-positive S. pseudintermedius isolates obtained from skin lesions and nasal orifices of 46 dogs with pyoderma enrolled at a referral hospital in Thailand between 2019 and 2020. All isolates underwent antibiogram profiling, SCCmec typing, and pulsed-field gel electrophoresis (PFGE) for phenotypic and genetic analysis. Among the 87 isolates, 33 isolates (37.9%) recovered from 15 dogs were oxacillin-resistant (OR-MRSP), while 54 isolates (62.1%) from 31 dogs were oxacillin-susceptible (OS-MRSP). All OR-MRSP isolates exhibited multidrug resistance (MDR), and 44% of the OS-MRSP isolates also showed MDR. SCCmec typing revealed type V as predominant among OR-MRSP isolates (69.7%), while many oxacillin-susceptible isolates (70.4%) were non-typeable. The OR-MRSP isolates from the same dog showed consistent antibiogram and SCCmec types, while OS-MRSP isolates displayed both identical and diverse patterns. No dominant pulsotypes were observed among the OR-MRSP or OS-MRSP strains. Genetic diversity was also noted among the isolates within the same dogs and among the others, highlighting the complexity of S. pseudintermedius colonization and infection dynamics in pyoderma-affected dogs.

Thermosensitive chitosan-based hydrogel: A vehicle for overcoming the limitations of nose-to-brain cell therapy

Cell therapy is a promising strategy for treating neurological pathologies but requires invasive methods to bypass the blood–brain barrier restrictions. The nose-to-brain route has been presented as a direct and less invasive alternative to access the brain. The primary limitations of this route are low retention in the olfactory epithelium and poor cell survival in the harsh conditions of the nasal cavity. Thus, using chitosan-based hydrogel as a vehicle is proposed in this work to overcome the limitations of nose-to-brain cell administration. The hydrogelʼs design was driven to achieve gelification in response to body temperature and a mucosa-interacting chemical structure biocompatible with cells. The hydrogel showed a < 30 min gelation time at 37 °C and >95 % biocompatibility with 2D and 3D cultures of mesenchymal stromal cells. Additionally, the viability, stability, and migration capacity of oligodendrocyte precursor cells (OPCs) within the hydrogel were maintained in vitro for up to 72 h. After the intranasal administration of the OPCs-containing hydrogel, histological analysis showed the presence of viable cells in the nasal cavity for up to 72 h post-administration in healthy athymic mice. These results demonstrate the hydrogel's capacity to increase the residence time in the nasal cavity while providing the cells with a favorable environment for their viability. This study presents for the first time the use of thermosensitive hydrogels in nose-to-brain cell therapy, opening the possibility of increasing the delivery efficiency in future approaches in translational medicine. Statement of significanceThis work highlights the potential of biomaterials, specifically hydrogels, in improving the effectiveness of cell therapy administered through the nose. The nose-to-brain route has been suggested as a non-invasive way to directly access the brain. However, delivering stem cells through this route poses a challenge since their viability must be preserved and cells can be swept away by nasal mucus. Earlier attempts at intranasal cell therapy have shown low efficiency, but still hold promise to the future. The hydrogels designed for this study can provide stem cells with a biocompatible environment and adhesion to the nasal atrium, easing the successful migration of viable cells to the brain.

Review of Intranasal Active Pharmaceutical Ingredient Delivery Systems.

In recent decades, there has been an increased interest in the development of intranasal delivery systems for active pharmaceutical ingredients (APIs) not only for treating local nasal diseases but also for treating systemic diseases, central nervous system (CNS) disorders, and vaccine delivery. The nasal cavity possesses a unique set of anatomical characteristics for delivering active pharmaceutical ingredients, but there are several limitations that recent research in the field of the intranasal administration of APIs aims to overcome. For the effective delivery of nasal preparations, active pharmaceutical ingredients are incorporated into various micro- and nanosystems. Some of the most commonly encountered API delivery systems in the scientific literature include liposomal systems, polymer particles with mucoadhesive properties, in situ gels, nano- and microemulsions, and solid lipid particles. This article provides a review of research on the development of nasal preparations for treating local nasal cavity diseases (in particular, for antibiotic delivery), systemic diseases (analgesics, drugs for cardiovascular diseases, antiviral and antiemetic drugs), CNS disorders (Alzheimer's disease, Parkinson's disease, epilepsy, schizophrenia, depression), and vaccine delivery. The literature data show that active research is underway to reformulate drugs of various pharmacotherapeutic groups into a nasal form.

The Bony Nasal Cavity and Paranasal Sinuses of Big Felids and Domestic Cat: A Study Using Anatomical Techniques, Computed Tomographic Images Reconstructed in Maximum-Intensity Projection, Volume Rendering and 3D Printing Models.

This study aims to develop three-dimensional printing models of the bony nasal cavity and paranasal sinuses of big and domestic cats using reconstructed computed tomographic images. This work included an exhaustive study of the osseous nasal anatomy of the domestic cat carried out through dissections, bone trepanations and sectional anatomy. With the use of OsiriX viewer, the DICOM images were postprocessed to obtaining maximum-intensity projection and volume-rendering reconstructions, which allowed for the visualization of the nasal cavity structures and the paranasal sinuses, providing an improvement in the future anatomical studies and diagnosis of pathologies. DICOM images were also processed with AMIRA software to obtain three-dimensional images using semiautomatic segmentation application. These images were then exported using 3D Slicer software for three-dimensional printing. Molds were printed with the Stratasys 3D printer. In human medicine, three-dimensional printing is already of great importance in the clinical field; however, it has not yet been implemented in veterinary medicine and is a technique that will, in the future, in addition to facilitating the anatomical study and diagnosis of diseases, allow for the development of implants that will improve the treatment of pathologies and the survival of big felids.

Mucoadhesive in situ nasal gel of amoxicillin trihydrate for improved local delivery: Ex vivo mucosal permeation and retention studies

Orally administered amoxicillin is recommended as the first-line treatment of acute bacterial rhinosinusitis (ABR) and given in a high-dose regimen. However, the risk of various systemic adverse reactions and low oral bioavailability are unbearable, increasing the threat of antibiotic resistance. Therefore, nasal delivery of amoxicillin can be a potential approach for effectively treating ABR locally, as well as overcoming those drawbacks. In a way to guarantee the effectiveness for local therapy in nasal cavity, the permeation and retention properties are of significant importance considerations. Accordingly, the present work aimed to investigate the characteristics with respect to the nasal applicability of the in situ gelling amoxicillin trihydrate (AMT) and further evaluate its permeability and retention properties through human nasal mucosa. The lyophilized formulations were characterized utilizing the Differential Scanning Calorimetry (DSC) and X-ray Powder Diffraction (XRPD), and also evaluated for its polarity, reconstitution time, droplet size distribution, mucoadhesive properties, and ex vivo permeability and retention studies. The results confirmed that the in situ gelling AMT formulations possess adequate mucoadhesive behavior, especially the formulation containing 0.3 % of gellan gum. Substantially, the in situ gelling AMT formulations were able to retain the drug on the surface of nasal mucosa instead of permeating across the membrane; thus, suitable for treating nasal infections locally. Altogether, the in situ gelling systems demonstrates promising abilities as a delivery platform to enhance local application of AMT within the nasal cavity.

A rare case of isolated melanoma of the sphenoid sinus

&lt;b&gt;Introduction:&lt;/b&gt; Sphenoid sinus melanoma is extremely rare – only 7 cases have been described in the available literature.&lt;b&gt;Aim:&lt;/b&gt; We present the next case of a 77-year-old female with melanoma of the left sphenoid sinus treated in our ENT Department.&lt;b&gt;Case study:&lt;/b&gt; A 77-year-old female was admitted to our department due to the histologically confirmed left sphenoid sinus malignant melanoma. During admission, the patient was treated with Pembrolizumab at the Oncology Center in Gliwice. In our department, she underwent endoscopic surgery of the left sphenoid sinus and nasopharynx six times. The patient’s last admission on 04/2023 was caused by the heavy epistaxis from the left nasal cavity. She died less than a year after the last surgical intervention (04/2023) due to the generalization of the neoplastic disease.&lt;b&gt;Conclusions:&lt;/b&gt; Malignant melanoma of the sphenoid sinus is an extremely rare neoplasm. The endoscopic resection of the tumor remains the treatment of choice. However, newer modalities like biologic and immunomodulatory treatments are being studied. The 5-year survival rates in these cases are only 10–15%.