Computer-Aided Diagnosis of Maxillary Sinus Anomalies: Validation and Clinical Correlation

OBJECTIVE

Computer aided diagnostics (CAD) systems can automate the differentiation of maxillary sinus (MS) with and without opacification, simplifying the typically laborious process and aiding in clinical insight discovery within large cohorts.

METHODS

This study uses Hamburg City Health Study (HCHS) a large, prospective, long-term, population-based cohort study of participants between 45 and 74 years of age. We develop a CAD system using an ensemble of 3D Convolutional Neural Network (CNN) to analyze cranial MRIs, distinguishing MS with opacifications (polyps, cysts, mucosal thickening) from MS without opacifications. The system is used to find correlations of participants with and without MS opacifications with clinical data (smoking, alcohol, BMI, asthma, bronchitis, sex, age, leukocyte count, C-reactive protein, allergies).

RESULTS

The evaluation metrics of CAD system (Area Under Receiver Operator Characteristic: 0.95, sensitivity: 0.85, specificity: 0.90) demonstrated the effectiveness of our approach. MS with opacification group exhibited higher alcohol consumption, higher BMI, higher incidence of intrinsic asthma and extrinsic asthma. Male sex had higher prevalence of MS opacifications. Participants with MS opacifications had higher incidence of hay fever and house dust allergy but lower incidence of bee/wasp venom allergy.

CONCLUSION

The study demonstrates a 3D CNN's ability to distinguish MS with and without opacifications, improving automated diagnosis and aiding in correlating clinical data in population studies.

LEVEL OF EVIDENCE

3 Laryngoscope, 2024.

Association of allergic rhinitis with hypothyroidism, asthma, and chronic sinusitis: Clinical and radiological features

Background

Allergic rhinitis (AR) is characterized by mucosal inflammation that leads to a variety of symptoms, such as nasal congestion, rhinorrhea, and sneezing. This rhinitis is triggered by inhalation of allergens, such as pollen, and this condition has a negative impact on the quality of life. AR was shown to be associated with a number of co‐morbidities, including hypothyroidism, asthma, and chronic sinusitis.

Objective

This study aimed to assess AR‐associated comorbidities in patients presenting symptoms and paranasal sinus computed tomography (CT) scan findings in Taif City, Saudi Arabia.

Methods

This cross‐sectional study evaluated medical and radiological records of AR patients retrospectively from the period of December 2018 to September 2019 in Al‐Hada Armed Forces Military Hospital, Taif City, Saudi Arabia.

Results

A total of 103 AR patients with a mean age of 39.0 ± 15.6 years with 55.3% males and 44.7% females. The three most common associated comorbidities in allergic rhinitis patients were chronic sinusitis (28.2%), hypothyroidism (21.4%), and asthma (8.7%). Nasal obstruction (30.1%) was the symptom most frequently presented by all patients. Mucosal thickening occurred most frequently in patients with associated chronic sinusitis, while bilateral osteomeatal complex obliteration was observed mostly in asthmatic patients, and bony boundary thinning was more prevalent among patients with associated hypothyroidism.

Conclusion

The gender distribution of AR was 10% more common among males; however, the most common three comorbidites in allergic rhinitis patients were chronic sinusitis, hypothyroidism, and asthma, and most of those patients were females. Hypothyroidism can be a hidden predisposing factor for AR, while chronic sinusitis can be caused by AR due to secretion stasis or immune system activation.

Anatomical Considerations and Study of the Fractal Dimension around the Posterior Superior Alveolar Artery

The Posterior Superior Alveolar Artery (PSAA) provides vascular support to molars, gingiva, and maxillary sinus. A tear of the PSAA may cause profuse hemorrhages which may lead to complications at a surgical level. As such, it becomes crucial to anatomically analyse several features regarding the PSAA as well as the area surrounding it. In this paper, we are particularly interested in the study of the complexity of the periodontal tissue structure which appears close to the location of the PSAA. A total amount of 400 cone beam computed tomography (CBCT) scans (two per subject) were performed to explore the presence of the PSAA, the thickness of the Schneider’s membrane, and the existence of septa. Several parameters were evaluated including the location of the artery in the maxillary sinus, the distance from the PSAA to the alveolar ridge, the thickness of the membrane, the diameter of the cavities produced by the septa, and the fractal dimension of the trabecular tissue that surrounds the PSAA. They were found strong linear relationships between Distal and Central Measures (a Pearson’s R 2 = 0.9952 ), Mesial and Central Measures ( R 2 = 0.9950 ), and Distal and Mesial Measure ( R 2 = 0.997 ). We hypothesised that the loss of dental pieces would imply a distinct complexity of the trabecular tissue structure surrounding the PSAA. In this way, a p-value equal to 0.001 was provided by the Mann-Whitney test, which supports our hypothesis. Furthermore, the mean of the fractal dimensions of the group of edentulous patients (equal to 1.56 ) was found to be lower than the one of the group of non-edentulous patients (equal to 1.61 ) with small standard deviations in both cases. Our study suggests that accurate calculations of the fractal dimension combined with the use of CBCT do provide valuable information regarding the area that surrounds the PSAA.

Effect of Nasal Obstructive Disorders on Sinonasal Symptoms in Children with Different Levels of Bronchial Asthma Control

Allergic rhinitis (AR) and allergic rhinosinusitis (ARS) are typical upper airway pathologies (UAP) in children with bronchial asthma (BA) frequently accompanied with nasal obstructive diseases (NOD). In order to establish the effect of NOD on correlations between nasal and synonasal symptoms with clinical assessments of asthma control, 82 children, 9.8 [8.9; 10.7] years old, with atopic BA were assessed using ACQ-5 for the BA control level, TNSS for nasal symptoms, and SNOT-20 for synonasal quality of life in combination with rhinovideoendoscopy for NOD. All patients had AR/ARS; in 76.3% (63/82) of children, UAP had a multimorbid character with the presence of NOD. Significant correlations were found between ACQ-5 and TNSS (R=0.40, p < 0.0001) and ACQ-5 and SNOT-20 (R=0.42, p < 0.0001). Correlations between TNSS/ACQ-5 and SNOT-20/ACQ-5 were higher in patients who do not have a combination of AR/ARS with NOD (R=0.67, p=0.0012; R=0.50, p=0.022, resp.) than in patients who have AR/ARS combined with NOD (R=0.30, p=0.015; R=0.26, p=0.04, resp.). Thus, the association of BA control level with the expression of nasal and synonasal symptoms is higher in children who do not have multimorbid UAP.

Acute and chronic rhinosinusitis and allergic rhinitis in relation to comorbidity, ethnicity and environment

Background

This study was conducted to assess the effect of comorbidity, ethnicity, occupation, smoking and place of residence on allergic rhinitis (AR), acute rhinosinusitis (ARS) and chronic rhinosinusitis (CRS).

Methods

A GA²LEN (The Global Allergy and Asthma European Network) screening questionnaire was sent to a random sample of the Dutch population (n = 16700) in three different areas of the Netherlands.

Results

Fifty percent (8347) of the questionnaires sent were returned. A total of 29% respondents (27–31% in different areas) met the criteria for AR, 18% (17–21%) for ARS and 16% (13–18%) for CRS. Risk factors for AR were itchy rash, eczema, adverse response after taking a painkiller, asthma, CRS and ARS. Moreover, the risk of AR was twice as low for full-time housewives/househusbands than for people with jobs. The risk of ARS or CRS was significantly higher in respondents with a doctor’s diagnosis of CRS, AR, itchy rash or smoking. The risk of CRS was also significantly higher in respondents with an adverse response after taking painkillers, active smoking or asthma. Caucasians are generally less likely to have AR or CRS than Latin-Americans, Hindustani and African-Creoles, and more likely to have ARS than Asian, Hindustani, Mediterranean and African-Creoles.

Conclusions

This study found shared and distinct risk factors for AR, ARS and CRS and therefore provides support for the belief that they have shared symptoms but are different diseases with different aetiologies.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Concha Bullosa: A Shield against Allergens?

PURPOSE

Concha bullosa (CB) alters the intranasal anatomy and may influence the buffering of inhalant allergens and the inflammatory microenvironment central to chronic rhinosinusitis (CRS). By investigating the link between allergies and CB, we can examine this theoretical benefit, which has implications on the extent of resection in endoscopic sinus surgery.

METHODS

Forty-three adults treated between 2010 and March 2014 with chronic sinonasal symptoms were retrospectively analyzed by skin prick allergy testing, maxillofacial computed tomography scan, and Lund-Mackay score. x03C7;2 analysis and t tests were employed to determine statistical significance.

RESULTS

Subjects were divided into 30 positive cases and 13 pan-negative allergy controls. No difference in CB prevalence was observed between those with positive (70%) and those with negative (69.2%) allergy tests (p = 0.93). Furthermore, no association between CB and Lund-Mackay score was identified (p = 0.69). Overall, 83.3% of CB were located in the middle turbinate, 16.7% in the superior turbinate, and 20% occurred in the middle turbinate bilaterally.

CONCLUSIONS

Although an enlarged, pneumatized turbinate could function as a physical barrier to inhalant allergens, documented allergies demonstrate no association with CB formation. Furthermore, this study finds no correlation between CB and radiographic evidence of CRS.

The Etiology and Pathogenesis of Chronic Rhinosinusitis: a Review of Current Hypotheses

Chronic rhinosinusitis (CRS) is a broad clinical syndrome that is characterized by prolonged mucosal inflammation of the nose and paranasal sinuses, and is typically divided into two subtypes based on the presence or absence of nasal polyps. The etiology and pathogenesis of both forms remain areas of active research. Over the last 15 years, a number of hypotheses have been proposed to explain all or part of the clinical CRS spectrum. These hypotheses reflect the concept that CRS results from a dysfunctional interplay between individual host characteristics and factors exogenous to the host. Six broad theories on CRS etiology and pathogenesis are discussed as follows: (1) the "fungal hypothesis," (2) the "superantigen hypothesis," (3) the "biofilm hypothesis," and (4) the "microbiome hypothesis," all of which emphasize key environmental factors, and (5) the "eicosanoid hypothesis" and (6) the "immune barrier hypothesis," which describe specific host factors. These theories are reviewed, and the evidence supporting them is critically appraised.

Ragweed-induced allergic rhinoconjunctivitis: current and emerging treatment options

Ragweed (Ambrosia spp.) is an annually flowering plant whose pollen bears high allergenic potential. Ragweed-induced allergic rhinoconjunctivitis has long been seen as a major immunologic condition in Northern America with high exposure and sensitization rates in the general population. The invasive occurrence of ragweed (A. artemisiifolia) poses an increasing challenge to public health in Europe and Asia as well. Possible explanations for its worldwide spread are climate change and urbanization, as well as pollen transport over long distances by globalized traffic and winds. Due to the increasing disease burden worldwide, and to the lack of a current and comprehensive overview, this study aims to review the current and emerging treatment options for ragweed-induced rhinoconjunctivitis. Sound clinical evidence is present for the symptomatic treatment of ragweed-induced allergic rhinoconjunctivitis with oral third-generation H1-antihistamines and leukotriene antagonists. The topical application of glucocorticoids has also been efficient in randomized controlled clinical trials. Combined approaches employing multiple agents are common. The mainstay of causal treatment to date, especially in Northern America, is subcutaneous immunotherapy with the focus on the major allergen, Amb a 1. Beyond this, growing evidence from several geographical regions documents the benefit of sublingual immunotherapy. Future treatment options promise more specific symptomatic treatment and fewer side effects during causal therapy. Novel antihistamines for symptomatic treatment are aimed at the histamine H3-receptor. New adjuvants with toll-like receptor 4 activity or the application of the monoclonal anti-immunoglobulin E antibody, omalizumab, are supposed to enhance conventional immunotherapy. An approach targeting toll-like receptor 9 by synthetic cytosine phosphate–guanosine oligodeoxynucleotides promises a new treatment paradigm that aims to modulate the immune response, but it has yet to be proven in clinical trials.

The association of premorbid diseases with chronic rhinosinusitis with and without polyps

PURPOSE OF REVIEW

To review the recent insights regarding the epidemiology of adult chronic rhinosinusitis (CRS), with particular attention to its association with other premorbid conditions. Identifying premorbid disease associations establishes potential risk factors for developing CRS and helps corroborate current postulates of the various pathophysiologic mechanisms involved with the development and persistence of paranasal sinus inflammation.

RECENT FINDINGS

Recent findings demonstrate that the diagnosis of CRS is associated with a higher premorbid prevalence of upper airway diseases, lower airway diseases, gastroesophageal reflux disease, diseases of epithelial tissues, autoimmune disorders, and psychiatric conditions. Although some of these conditions have long been associated with CRS, improvements in study design and future studies in the general population will more accurately estimate the relative strengths of associations, clinical relevance, and temporal relationship of these various conditions in relation to the development of CRS.

SUMMARY

The predisposing patterns of premorbid illnesses may provide valuable information regarding the underlying causes of CRS and allow for both therapeutic and preventive interventions. There remains conflicting evidence within the literature regarding the association of CRS with some medical conditions, signifying the need for continued research on the subject. Limitations of the current studies include small sample sizes, lack of prospective longitudinal or interventional studies that help establish causality, and variable criteria for diagnosis of CRS in the outpatient setting.

Chronic rhinosinusitis and antibiotics: the good, the bad, and the ugly

BACKGROUND

Despite the recognition that bacteria are universally present in the sinuses of patients with chronic rhinosinusitis (CRS) no compelling role for a primary infectious etiology of CRS has been elucidated. CRS is a constellation of inflammatory diseases that typically involve either noneosinophilic or eosinophilic processes, distinct conditions that must be treated individually.

METHODS

The bacteria that are present in the sinuses may be innocuous bystanders but alternatively may contribute to the presence and severity of the disease through their ability to influence immune responses, function as immune adjuvants, provide antigens or superantigens that contribute to adaptive immune activation, or in forming the basis for the frequent acute superinfections. However, those bacteria that do contribute to the persistence and severity of CRS primarily reside in biofilms, and, as such, are not capable of being eradicated with antibiotics at the doses at which they can be used, even when local irrigation is considered.

RESULTS

Biofilms create an inhospitable environment for antibiotic potency by down-regulating the metabolic activity of their "core" bacteria, decreasing the oxygen concentration, and altering the pH at the core of the biofilm.

CONCLUSION

Ultimately, if topical antibiotics are considered, they should be primarily focused on treating acute exacerbations and choices of antibiotics should optimally be based on endoscopic culture. This should be done with the recognition that while under certain circumstances antibiotics can ameliorate the severity of CRS, even if bacterial eradication were possible, this would not eliminate the underlying primary pathogenic mechanism or the natural history of these conditions.

Prevalence of and associations with allergic rhinitis in children with chronic rhinosinusitis

OBJECTIVES

Chronic rhinosinusitis (CRS) in children has been associated with a variety of disorders including atopic disease, cystic fibrosis, immunologic disorders and ciliary dyskinesia. Although a strong association, or even cause and effect relationship, between allergic rhinitis (AR) and CRS is commonly assumed, the epidemiologic relationship between these disorders has not yet been defined in children.

METHODS

A retrospective review of all children diagnosed with CRS on otolaryngology or allergy office evaluation at a large tertiary-care pediatric hospital over a ten-year period was performed. Demographic data and concomitant diagnoses of AR, cystic fibrosis, immunologic disorders and primary ciliary dyskinesia were analyzed for relationships with CRS.

RESULTS

A total of 4044 children with an average age of 8.9 years and a slight male predominance (53.8%) with CRS were identified. Of these children, 0.2% had primary ciliary dyskinesia, 4.1% had cystic fibrosis, 12.3% had an immunologic disorder, and 26.9% had AR. A concomitant asthma diagnosis was positively associated with a diagnosis of AR (OR=6.24, 95% CI: 5.27-7.39, P<0.001), whereas a concomitant cystic fibrosis diagnosis was negatively associated (OR=0.12, 95% CI: 0.06-0.26, P<0.001).

CONCLUSIONS

AR is more prevalent than the other comorbidities combined in children with CRS, and is independently associated with the presence of asthma. Formal allergy testing, guided by clinical history and regional allergen sensitivity prevalence, should be strongly considered in all children with CRS, in particular those with reactive airway disease.

Chronic sinusitis pathophysiology: the role of allergy

BACKGROUND

Chronic hyperplastic eosinophilic sinusitis (CHES) is an inflammatory disease characterized by eosinophil infiltration of sinus tissue that can present with and without nasal polyps (NPs). Aeroallergen sensitization in CHES occurs regularly, but the causality between allergen sensitivity, exposure, and disease is unclear.

METHODS

Allergen is unlikely to directly enter healthy sinuses either by diffusion or ciliary flow, and, even this is more problematic given the loss of patency of the ostia of diseased sinuses. Inflammation and tissue eosinophilia can develop secondary to allergen exposure in the nares, with systemic humoral recirculation of allergic cells including eosinophils, Th2 lymphocytes, and eosinophil precursors that are nonspecifically recruited back to the diseased sinuses.

RESULTS

The possibility of an allergic reaction to peptides derived from bacteria (i.e., Staphylococcus or superantigens) or fungi that colonize the diseased sinus also provides a plausible allergic mechanism.

CONCLUSION

Treatments of this disease include agents directed at allergic mediators such as leukotriene modifiers and corticosteroids, although this does not necessarily signify that an IgE-dependent mechanism can be ascribed. However, more recently, omalizumab has shown promise, including in patients without obvious aeroallergen sensitization. Although many aspects of the role of allergy in CHES remain a mystery, the mechanisms that are being elucidated allow for improved understanding of this disease, which ultimately will lead to better treatments for our patients who live daily with this disease.

Unilateral nasal allergic reactions increase bilateral sinus eosinophil infiltration

We have previously shown that unilateral nasal challenge with antigen causes an increase in the number of eosinophils in the ipsilateral maxillary sinus. Here we aimed to determine whether there was an eosinophil response in the contralateral maxillary sinus after unilateral nasal challenge with antigen. Twenty subjects with a history of seasonal allergic rhinitis and a positive nasal challenge to ragweed or grass allergens were studied outside of their allergy season. Catheters were placed in both maxillary sinuses and the subjects were challenged with antigen via the left nostril. The subjects recorded nasal symptoms before and after each allergen challenge and hourly for 8 h afterward. We performed nasal lavages of the nose and sinuses at the same time as symptoms were recorded. The lavages were analyzed for the number of eosinophils and levels of albumin. Subjects showed a symptomatic response to challenge accompanied by an influx of eosinophils into the nose and increased vascular permeability. The number of eosinophils increased in both maxillary sinuses. The total change from diluent in eosinophils during the late phase response was higher in the ipsilateral maxillary sinus (median = 8,505; range = 0-100,360) compared with the contralateral sinus (median = 1,596; range = -13,527-93,373; P = 0.03). We conclude that eosinophils increase in both maxillary sinuses after unilateral nasal challenge. We speculate that a central neurologic reflex initiated in the nose by the nasal challenge contributes to the bilateral eosinophil response in the maxillary sinuses. We further speculate that, since there are more eosinophils in the ipsilateral compared with the contralateral maxillary sinus, there is also an axonal reflex into the ipsilateral maxillary sinus that contributed to the eosinophil response.