Sinus Computed Tomography Research Articles

Analysis of Lamina Papyracea Area and Ethmoid Sinus Volume in Indonesian Patients Undergoing Paranasal Sinus CT Scan

Of the rhinosinusitis (CRS) patients, half of whom require surgical intervention. Functional endoscopic sinus surgery (FESS) is a standard treatment of CRS and sinonasal polyposis. Orbito-ocular complications can occur during FESS. The lamina papyracea (LP) is the weakest point of the medial wall of the orbit. The variability in the size and shape of the paranasal sinuses is important in the FESS procedure. The ethmoid sinus is the most complex paranasal sinuses. Preoperative evaluation using computed tomography (CT) is mandatory for all patients undergoing FESS. This study aimed to determine the lamina papyracea area and ethmoid sinuses volume in patients who underwent a CT scan of paranasal sinuses. This study was a descriptive study on 103 patients who underwent a CT scan of paranasal sinuses in the Radiology Department of Hasanuddin University General Hospital, Makassar, from January to August 2019. The lamina papyracea area and ethmoid sinus volume were measured based on age and gender. The results showed that the average of lamina papyracea size and ethmoid sinus volume was greater in males than in females. There was a correlation between age and posterior height of left lamina papyracea (p=0.02), but no correlation between ethmoid sinuses volume and age.

Digital diaphanoscopy of the maxillary sinuses: A revival of optical diagnosis for rhinosinusitis.

The non-invasive diagnosis of acute rhinosinusitis (ARS) remains an unresolved problem of modern otolaryngology. Analog diaphanoscopy of reduced transillumination (shading) could be enhanced by a digital image processing of the maxillary sinuses. By this means, the limited ergonomics of this safe and low-cost method can be overcome, and merits renewed the investigation. Here, we compared the diagnostic sensitivity and specificity of digital diaphanoscopy and computed tomography (CT) in detecting shading in the maxillary sinus. We examined 103 adults using both digital diaphanoscopy of the maxillary sinus and native-phase cranial CT. We developed a scoring system for investigation of shading in the maxillary sinus using diaphanoscopy and compared the sensitivity and specificity with that of CT. Also, we documented a follow-up of acute rhinosinusitis. In diagnosing shading in the maxillary sinus, digital diaphanoscopy had a sensitivity of 86% and a specificity of 88%. Digital diaphanoscopy can be used not only in the screening of ARS but also for documentation of its course. This study supports the role of modern digital diaphanoscopy in the diagnosis of shading in the maxillary sinus, especially in patients with ARS when CT imaging is not recommended. The ergonomics of analog diaphanoscopy could be significantly improved for physicians and patients by the implementation of modern hardware and software components. Further development of the technique and the use of several discrete wavelengths will improve this method's sensitivity and specificity.

Olfactory Cleft Width and Volume: Possible Risk Factors for Postinfectious Olfactory Dysfunction.

Upper respiratory tract infections are a common cause of temporary and permanent olfactory dysfunction in the general population. Postviral or postinfectious olfactory loss (PIOL) develops only in rare cases. The aim of this study was to investigate the anatomical features of olfactory cleft (OC) in patients with PIOL to shed light on possible predisposing factors for PIOL. Retrospective study. We retrospectively evaluated paranasal sinus computed tomography (CT) scan results of patients diagnosed with PIOL. A control group consisted of normosmic individuals who underwent paranasal sinus CT scans before septoplasty surgery. We compared the olfactory fossa depth, OC width, and volume on the CT scans of the PIOL and control groups. In total, 71 individuals fulfilled the study criteria (PIOL group, n = 32; control group, n = 39). There was no statistically significant difference in the olfactory fossa depth in the two groups. The OC width and volume in the PIOL group was found to be significantly increased than that in the control group (P < .001 for both). Patients with PIOL had increased OC width and volume than the healthy controls. An extra-wide olfactory cleft may be a predisposing factor in the pathogenesis of PIOL. 4 Laryngoscope, 131:5-9, 2021.

The cotton test redistributes nasal airflow in patients with empty nose syndrome.

Empty nose syndrome (ENS) remains a controversial disease primarily associated with inferior turbinate tissue loss. Cotton placement into the inferior meatus often alleviates ENS symptoms within minutes, but the physiologic explanation for this phenomenon is unknown. Computational fluid dynamics (CFD) was employed to evaluate the mechanisms of altered nasal airflow conferred by cotton testing. Six ENS patients (12 sides) with pre-existing sinus computed tomography (CT) imaging were enrolled after marked symptomatic improvement (decrease in score on the Empty Nose Syndrome 6-Item Questionnaire [ENS6Q] of >7 points) with office-based cotton testing. The fashioned cotton plug was labeled in situ with iohexol contrast spray, and sinus CT was immediately obtained to detect cotton contouring in the inferior meatus. CT imaging from pre- and post-cotton placement was analyzed using comparative CFD techniques. After cotton placement, significant symptomatic improvement and reduced ENS6Q scores (16.8 ± 4.1 to 3.1 ± 2.4; p < 0.001) were recorded. Using CFD, cotton placement produced an expected 21% increase in upper airway resistance (p < 0.05). However, a significant shift in the nasal airflow distribution was also detected, with a transition of airflow vectors away from a middle meatus jetstream (-41%; p < 0.002). Objective CFD assessment confirmed that the cotton test not only increases nasal resistance, but also restores airflow distribution to the inferior meatus in symptomatic ENS patients. These results highlight the potential efficacy of cotton test in ENS patients and further bolster the utility of this tool in identifying appropriate candidates for the inferior meatus augmentation procedure.

Variability of Paranasal Sinus Pneumatization in the Absence of Sinus Disease.

Background: Paranasal sinus pneumatization is a complex process, and numerous computed tomography (CT) studies document developmental variations in the setting of underlying sinus disease. The purpose of this study was to investigate variation in paranasal sinus pneumatization in a population of nondiseased subjects using a metric validated for tracking individual anatomic variants as well as total sinus volume.Methods: A total of 591 consecutive sinus and maxillofacial CT scans were considered for study inclusion. After patients with inflammatory sinus or respiratory disease were excluded, 323 CT scans were scored using the Assessment of Pneumatization of the Paranasal Sinuses (APPS) instrument, and relevant demographic data were recorded for each scan. APPS findings were compared according to demographic characteristics and laterality.Results: Laterality and sex were associated with differences in paranasal sinus pneumatization in a nondiseased population. Based on APPS score, the left side (4.95) was more pneumatized than the right (4.74, P=0.006), and males (10.16) were more extensively pneumatized than females (9.18, P=0.005). We found no correlation of age with sinus pneumatization (ρ=0.025). The probability of perceptible asymmetry in any given individual's paranasal sinus pneumatization was 69%, and the probability of left-sided dominance was 53%.Conclusion: Substantial anatomic variation exists in paranasal sinus anatomy, even among patients without sinus disease. Significant differences are found between males and females and between the left and right sides. Continued systematic research of paranasal sinus anatomy may facilitate a standard for CT sinus assessment that will aid clinician evaluation of anatomic variation and surgical decision making.

Use of Nasal Nitric Oxide in the Diagnosis of Allergic Rhinitis and Nonallergic Rhinitis in Patients with and without Sinus Inflammation

Nasal nitric oxide (nNO) has been evaluated in patients with chronic rhinosinusitis with and without nasal polyps. However, nNO levels in patients with allergic rhinitis (AR) and nonallergic rhinitis (NAR) have shown conflicting results in previous studies. To evaluate the value of nNO in diagnosing AR and NAR and the impact of absence or presence of sinus inflammation (SI). A total of 173 consecutive patients scanned with high-resolution computed tomography (CT) and 46 normal controls (NCs) were included in our study. Patients were evaluated according to their medical history, nasal symptoms, endoscopic examinations, and skin prick test results. On the basis of CT scans (Lund-Mackay score >2), all patients were subgrouped as AR with SI (ARwSI) and AR without SI (ARsSI), or NAR with SI (NARwSI) and NAR without SI (NARsSI). nNO levels were measured with the NIOX, and eosinophils in nasal smears were evaluated simultaneously. Receiver-operating characteristic analysis was performed for differential diagnosis of AR, NAR, and subgroups. Ninety-four patients were diagnosed with AR and 79 patients with NAR. The levels of nNO were significantly higher in patients with AR and in NCs compared with patients with NAR (939 ± 335 in AR and 813 ± 272 in NCs vs 670 ± 188 in NAR; P < .001 for both), and significantly higher in patients with AR compared with NCs (P < .05). On the basis of sinus CT scans, 49% patients with AR (46 of 94) were defined as ARwSI and 51% patients with NAR (40 of 79) were defined as NARwSI. Patients with ARsSI showed the highest nNO levels (1180 ± 289) compared with other subgroups (P < .001), and patients with NARwSI showed the lowest nNO levels (522 ± 120) compared with other subgroups (P < .001). nNO could be used to discriminate AR, NAR, and subgroups with acceptable sensitivity and specificity. Moreover, patients with nasal smear eosinophilia had lower nNO levels than did patients with NAR (P < .05). nNO levels are different between patients with ARwSI/ARsSI and NARwSI/NARsSI, and may be used to discriminate these phenotypes.

Anatomic Sphenoid Cell Variants: Introduction of the Retrosphenoid Cell and Relevance in the Presentation and Management of Sinus Disease.

Background Despite the well-appreciated variability in sphenoid sinus anatomy, there are no documented cases of retrosphenoid cells in the literature to date. Objective This study defines and determines the prevalence of retrosphenoid cells as identified on computed tomography (CT) imaging and intraoperative endoscopy and reviews the prevalence of other related anatomical variants of the sphenoid sinus. Methods Retrospective study of 300 random noncontrast sinus CT scans of patients with chronic rhinosinusitis presenting to a tertiary rhinology center. All identifiable anatomic variations and any presence of retrosphenoid cells and their pneumatization patterns were recorded. The prevalence of various anatomic variations of the sphenoid sinus was also calculated. Results A total of 300 sinus CT scans were included in the study. Protrusion of both the internal carotid artery (42.6%) and optic nerve (19.7%) into the sinus was more prevalent than the dehiscence of either one. A retrosphenoid cell was identified in 2% of CT scans. Other anatomic variants were less prevalent. Conclusion Meticulous review of preoperative imaging is key in identifying rare and complex sphenoid cell variations in planning surgical approaches and potential treatment strategies for the unusually pneumatized sphenoid air cells. Various manifestations of sinus disease can be localized to this area, and suspicion of a retrosphenoid cell should be raised in patients presenting with recalcitrant headache.

Characterization of Sinus Disease in Patients with Yellow Nail Syndrome.

Objective Yellow nail syndrome (YNS) is characterized by the triad of thickened yellow nails, primary lymphedema, and respiratory manifestations including bronchiectasis, chronic cough, pleural effusions, and sinusitis. The purpose of this study is to describe the manifestations of chronic rhinosinusitis (CRS) in patients with YNS and the comorbid manifestations. Methods A retrospective review of patients with YNS with CRS from January 1, 1998 to January 1, 2018 was conducted. Their symptoms, comorbidities, and labs were reviewed. The patient’s sinus computed tomography (CT) scans were then scored using the Lund–Mackay (LM) scoring system. Result Thirty-six patients met the inclusion criteria. The average LM score was 10.2 ± 0.5 (mean ± SD). Sinus involvement included “frothy” dependent sinus secretions in 32 of 36 subjects. The most common location of sinus involvement was the maxillary sinuses (85%), then posterior ethmoid (81%), anterior ethmoid (76%), sphenoid (74%), and frontal sinuses (54%). Comorbid chronic cough (86%), bronchiectasis (65%), lymphedema (39%), and pleural effusion (19%) were also identified. Three patients (8%) had immunodeficiencies. Conclusion This is the largest series describing the sinus manifestations of CRS in patients with YNS. Sinus CT scans showed frothy dependent secretions in the maxillary sinuses and posterior ethmoid sinuses most commonly. YNS patients with sinusitis more commonly presented with chronic cough or bronchiectasis than with pleural effusions or lymphedema. Otolaryngologists should consider the possibility of YNS in patients with CRS, chronic cough, yellow or thickened nail, and CT findings of frothy, dependent sinus secretions.

Odontogenic sinusitis is a common cause of unilateral sinus disease with maxillary sinus opacification.

Unilateral sinus disease (USD) carries a broader differential diagnosis than bilateral sinus disease, including various inflammatory and neoplastic conditions. Odontogenic sinusitis (ODS) is a common cause of unilateral maxillary sinusitis, but few studies have examined its incidence among all USD etiologies. The main purposes of this prospective study were to determine the incidences of ODS and other etiologies causing USD with complete maxillary sinus opacification on computed tomography (CT), and to compare CT features of ODS and non-odontogenic USD patients. In addition, clinical features of the ODS cohort are described. A prospective case series of 134 patients with USD with complete maxillary sinus opacification on CT was conducted from August 2015 to November 2018. Based on nasal endoscopy, sinus CT, and dental examination and imaging, patients were categorized as having unilateral ODS or non-odontogenic USD. Patients with non-odontogenic USD were categorized as inflammatory or neoplastic. Demographic and clinical data were reported for ODS patients. Of the 134 patients, 45% had ODS, 36% had non-odontogenic inflammatory conditions, 17% had inverted papilloma, and 2% had malignancies. Of the 60 ODS cases, 86.7% were associated with middle meatal purulence on nasal endoscopy. On CT, 88.3% had extramaxillary sinus disease extension, and 65.5% of CT reports made no mention of dental pathology. ODS caused nearly 50% of all USD cases with maxillary sinus opacification on CT, and was the most common individual etiology. ODS was frequently associated with anterior ethmoid and frontal sinus disease on CT, and middle meatal purulence on nasal endoscopy.

Classification of anatomical variants of maxillary sinus shapes and symmetry using computerized tomographic imaging

Background: The maxillary sinus is characterized by a considerable variation in sizes and shapes and between the right and left sides. Due to easy access to all its walls and surfaces, imaging via computerized tomography (CT) has enhanced the quality and quantity of information obtainable from the assessment of the maxillary sinus. Aim: To determine normal variations in shapes and symmetry of the maxillary sinus using CT. Methods: A total of 130 subjects comprising 79 males and 51 females, between the ages of 20 and 80 years, with normal maxillary sinus CT anatomy, who had head CT scans carried out at the Radiology Department of the Usmanu Danfodiyo University Teaching Hospital (UDUTH) Sokoto, over a period of five years, were used for this study. Images were taken with a GE Bright Speed Multidetector Helical CT (GE Healthcare, USA, 2005) Scanner, while films were viewed on the computer monitor. Variations in shapes of the maxillary sinus were identified on axial images and classified based on their resemblance to known shapes of solids. Data were analyzed using Minitab 16.0 statistical package (Minitab inc. USA). Results: Five distinct shapes of the maxillary sinus were identified. These were: irregular in two subjects (0.77%) (right = 1 and left = 1); oval in three subjects (1.15%) (right = 2 and left = 1); quadrangular in three subjects (1.15%) (right = 2 and left = 1); spherical in 61 subjects (23.46%) (right = 30 and left = 31); and triangular 191 (73.46%) (right = 95 and left = 96). Shapes were symmetrical in 85.38% and asymmetrical in 14.62% of subjects. Conclusion: Five normal but distinct shapes of the maxillary sinus were identified, with the predominant shape, being the triangular type, and sinuses of individuals were frequently symmetrical in shape.

Endoscopic sinus surgery for pediatric patients: Prognostic factors related to revision surgery.

In the past two decades, endoscopic sinus surgery (ESS) has been performed frequently in children with medically recalcitrant chronic rhinosinusitis (CRS). However, surgical success rates vary according to age. The causes of failure and prognostic factors for revision ESS remain unclear. The aims of the present study were to evaluate prognostic factors related to revision surgery after ESS, and to determine the most optimal timing for surgery in the pediatric population. This was a retrospective review in a tertiary medical center. Children who underwent ESS for CRS between 2004 and 2017 were enrolled. Demographics, sinonasal examination findings, previous operation history, laboratory data, comorbidities, and computed tomography (CT) results were collected from medical records. Prognostic factors for revision surgery were analyzed. A total of 188 pediatric patients were enrolled in this study. Twenty-four patients (12.8%) required revision surgery. Multivariate logistic regression analysis identified patients with nasal allergy (OR = 6.258; P = .010) and higher Lund-Mackay score on preoperative sinus CT (OR = 1.658; P = .043) had worse outcomes, while older age was a positive prognostic factor (OR = 0.702; P = .018). A cut-off point of 15.68 years of age and mean Lund-Mackay score of 10.5 showed the best predictive power for revision surgery. Because ESS is performed with increasing frequency in children, knowledge of prognostic factors for revision surgery is important. In this study, patients with younger age, nasal allergy, and higher Lund-Mackay score on preoperative sinus CT had worse outcomes. 4 Laryngoscope, 130:1051-1055, 2020.

Association Between Endoscopic, Radiologic and Patient-reported Chronic Rhinosinusitis with Nasal Polyps

Objectives: Chronic Rhinosinusitis without Nasal Polyps (CRSsNP) and with Nasal Polyps (CRSwNP) affect 10% and 1-4% of the general population respectively. Early detection and treatment of CRSwNP might prevent recalcitrant disease forms. The aim of this prospective controlled study was to evaluate association between endoscopic, radiologic, and self-reported CRSwNP, and a family history in defining CRSwNP. Methods: This study involved 73 CRS patients aged 18 years or over undergoing CRS-surgical consultation at the Tampere University Hospital. Data of sinus Computed Tomography (CT) scans and nasal endoscopy was obtained from patient records. Sixty controls ±allergic rhinitis underwent clinical examination. All subjects filled a questionnaire. Associations were analyzed by Chi square and adjusted regression models. The predictive performance of various parameters was assessed using the Area Under the Receiver Operating Characteristic curve (AUROC). Results: A total of 33% of CRSwNP patients reported not having Nasal Polyps (NPs), while 18% of CRSsNP patients reported having NPs (p &lt; 0.001). Radiologic Nasal Polyp (NP) score differentiated CRSwNP from CRSsNP with an AUROC of 0.95 (95% CI 0.91-1.00). The AUROC value for Lund-Mackay (LM) score was 0.84 (0.75-0.94). Positive family history of NP did not differ significantly between CRS and control groups. Family history of allergy or asthma was given with certainty, whereas CRS patients had uncertainty of reporting NPs in family compared to controls (adjusted OR=6.02, 95% CI 1.98-18.30, p = 0.002). Conclusion: Our findings suggest that in situations where nasal endoscopy cannot be performed, early detection of CRSwNP could result from information obtained from sinus CT scans and patients, in comparison to family history which has lower predictive value. However validation studies with larger sample sizes are still needed.

Critical Evaluation of Sinonasal Disease in 64 Adults with Primary Ciliary Dyskinesia.

To date, no study precisely described ear, nose and throat (ENT) disease in adults with primary ciliary dyskinesia (PCD) and its relationship with ciliary function/ultrastructure. A retrospective study of standardized ENT data (exam, audiogram, sinus Computed tomography (CT), and bacteriology) was conducted in 64 adults with confirmed PCD who were followed in two ENT reference centers. Rhinorrhoea and hearing loss were the main symptoms. Symptom scores were higher in older patients. Nasal endoscopy was abnormal in all patients except one, showing nasal polyps in one-third of the patients and stagnant nasal mucus secretions in 87.5% of the patients. Sinus CT opacities were mainly incomplete and showed one-third of the patients with sinus hypoplasia and/or agenesis. Middle meatus mainly grew Haemophilus influenzae, Streptoccocus pneumoniae and Pseudomonas aeruginosa. Otitis media with effusion (OME), which is constant in childhood, was diagnosed in less than one-quarter of the patients. In two-thirds of the patients, audiogram showed hearing loss that was sensorineural in half of the patients. ENT disease severity was not correlated with ciliary function and ultrastructure, but the presence of OME was significantly associated with a forced expiratory volume (FEV1) < 70%. Rhinosinusitis is the most common clinical feature of PCD in adults, while OME is less frequent. The presence of active OME in adults with PCD could be a severity marker of lung function and lead to closer monitoring.

Image Optimization and reduction of radiation dose in CT of the paranasal sinuses

Introduction: Since demand for computed tomography (CT) examinations is growing, patients are exposed more frequently to ionizing radiation. To reduce the dose delivered to patients in each scan, CT technologists can change the image acquisition parameters. However, this reduces image quality. Present study aimed to optimize and reduce radiation dose in a CT of the paranasal sinuses while minimizing deterioration of image quality Materials and Methods: We divided the patients into two study groups: Group A was scanned axially and coronally using default parameters, while Group B was scanned axially and coronally using new parameters. The patients’ organ doses were estimated using the ImpactDose calculator. The tube voltage, tube current, pitch, rotation time, and other parameters were then reduced and optimized. After reconstruction and analysis, all of the images were of good diagnostic quality in both groups Results: Using the new parameters, good agreement was found between the direct and reconstructed images. The CT parameters were reduced by the following proportions: kVp— 16.6%, mA—75%, rotation time—20%, and mAs—80%. However, these reductions did not obscure any anatomical landmarks. These parameters reduced the CTDIw, CTDIvol and DLP by 88.2%, 91.3%, and 91.3% respectively. Conclusion: In conclusion, the results suggest that the use of a Bone algorithm reduces the total amount of radiation used during CT of the sinuses. We recommend using these parameters in children, in the evaluation of facial trauma, and in emergency CT of the paranasal sinuses

35-Year-Old Man With Episodic Fever and Cough

35-Year-Old Man With Episodic Fever and Cough

Investigation of Distances Between the Anterior Nasal Spine and Nasofrontal Beak, Basal Lamella, Skull Base, and Sphenoid Sinus on Paranasal Sinus Computed Tomography.

The aim of this study was to investigate the distances between the anterior nasal spine and basal lamella (BL), skull base, nasofrontal beak (NfB), and the anterior wall of sphenoid sinus on computed tomography (CT) images. A total of 160 patients who were seen at the otolaryngology clinic of our institution were evaluated with the help of the image processing software of the radiology department. Cases in which bony structures could not be seen clearly because of previous surgery or trauma were excluded. The distance between the anterior nasal spine; and NfB, the closest point of the skull base in the frontal recess (SB1), the closest point of the BL, the intersection of the line with which the distance to the BL was measured with the skull base (SB2) and the closest point of the anterior wall of the sphenoid sinus (Sp) were measured using multiplanar reconstruction. The images of 140 patients were examined. NfB, SB1, BL, SB2, and Sp were 5.14 ± 0.46 (4.15-6.38) cm, 5.70 ± 0.48 (4.31-7.03) cm, 4.84 ± 0.44 (3.86-5.98) cm, 6.23 ± 0.50 (5.13-7.35) cm, and 6.14 ± 0.46 (5.04-7.36) cm, respectively. In our study group, the distances some of which were reported as constant values in the literature were found to have a range of up to 2 cm. Therefore, if distances between structures are to be used for orientation during endoscopic sinus surgery, they should be better measured preoperatively on paranasal sinus CT scan images instead of using predefined constant values.

Sinus computed tomography predicts clinical response to corticosteroids in chronic rhinosinusitis with nasal polyps.

BackgroundChronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous inflammatory disease usually characterized by chronic eosinophilia in the sinonasal mucosa, which often requires glucocorticoid (GC) therapy. However, the therapeutic response varies markedly between individuals. The objective of this study was to evaluate the diagnostic values of sinus computed tomography (CT) for GC-sensitivity in patients with CRSwNP.MethodsWe conducted a prospective, single-blinded study of 47 consecutive patients with CRSwNP. These patients were given a course of oral prednisone (30 mg daily for 14 days) and subsequently classified into objectively GC-sensitive and -insensitive subgroup according to the change in nasal polyp size score, or subjectively GC-sensitive and -insensitive subgroup according to the change in total nasal symptom score. The following parameters were compared between GC-sensitive and GC-insensitive subgroups: Lund-Mackay scores, olfactory cleft (OC) scores, and blood eosinophil counts and ratio (percentage of the total white blood cells).Results25/47 (53.2%) and 29/47 (61.7%) patients were objectively and subjectively sensitive to GC therapy, respectively. The OC score and the blood eosinophil counts and ratio in GC-sensitive subgroup were significantly higher than those in GC-insensitive subgroup, defined either objectively or subjectively. Multivariate logistic regression revealed that OC score was independent risk factor for objective or subjective GC-sensitivity. The OC score exhibited comparable accuracy with the blood eosinophil ratio as predictor of objective and subjective GC-sensitivity (the OC score AUC = 0.775 and 0.829, respectively). A OC score of 3.5 could act as a reliable indicator for predicting the clinical response to GC therapy in CRSwNP.ConclusionOur prospective findings validate the potential value of sinus CT scan in predicting GC-sensitivity in CRSwNP patients.

Glucocorticoid receptor isoform expression in peripheral blood mononuclear leukocytes of patients with chronic rhinosinusitis.

In several inflammatory disorders, altered peripheral blood mononuclear leukocyte (PBML) glucocorticoid (GC) receptor isoform expression has been associated with GC resistance and disease severity. However, it is unclear if PBML GC receptor isoforms are expressed differentially and are associated with worsened disease severity in chronic rhinosinusitis (CRS). PBMLs were isolated from control (n = 8), CRS without nasal polyps (CRSsNP) (n = 8), atopic CRS with nasal polyps (CRSwNP) (n = 8), non-atopic CRSwNP (n = 8), and allergic fungal rhinosinusitis (AFRS) (n = 8) patients. Demographics, atopic status, asthmatic status, 22-item Sino-Nasal Outcome Test (SNOT-22) scores, Lund-Kennedy nasal endoscopy scores, Lund-Mackay sinus computed tomography (CT) scores, Kennedy Osteitis scores, and GC utilization 6 months postoperatively were collected. Intracellular immunostaining was then performed for functional GC receptor α (GCRα) and nonfunctional GC receptor β (GCRβ), followed by flow cytometry analysis of geometric mean fluorescent intensity (MFI) and the percentage of cells expressing each GC receptor isoform. Compared to controls, each CRS subtype had decreased PBML GCRα and GCRα:GCRβ MFI expression, but no difference in GCRβ expression. Decreasing PBML GCRα in AFRS was associated with increasing Lund-Mackay sinus CT scores (r = -0.880, p =0.004). No significant associations were found between GC receptor isoform expression and other clinical measures. CRS patients have reduced functional PBML GCRα expression and decreased GCRα:GCRβ compared to controls. Reductions in GCRα in AFRS are associated with worsening Lund-Mackay sinus CT scores. The clinical implications of decreased functional GC receptor expression merits further investigation.

Image quality and dose reduction in sinus computed tomography using iterative reconstruction: a cadaver study.

Concerns about radiation dose in computed tomography (CT) imaging have renewed interest in iterative reconstruction (IR), a technique which has the potential to produce images with less noise at lower radiation doses than traditional filtered back projection (FBP). This study aimed to assess whether application of IR could provide comparable quality sinus CT images to FBP at lower kilovolt (kV) and milliamp (mA) settings, and to establish optimal scan settings for sinus imaging. 30 sinus CT scans were performed on 5 cadaver heads at two kV setting and three mA settings. Each scan was reconstructed using FBP and 3 IR settings, yielding a total of 120 images series. Each image set was blinded and randomly reviewed by 3 rhinologists and 2 neuroradiologists. Using a 5-point Likert scale, 16 anatomical landmarks, were graded with respect to image quality. Data were assessed with respect to dose and IR settings using statistical analysis. Higher kV and mAs settings produced significantly higher quality images for structure identification across all 16 landmarks; however, the suitability for surgery did not increase in a linear fashion and plateaued by a total radiation dose of 0.1201 mSv. IR algorithm did not provide a benefit in the overall score of scans at a fixed kV and mAs. Identification of structures in sinus CT imaging significantly correlate with the kV and mA and overall dose of radiation; however, IR did not provide additional benefit in the image quality.

Low-Dose Noncontrast Examination of the Paranasal Sinuses Using Volumetric Computed Tomography.

The objective of this study was to evaluate image quality of low dose in noncontrast paranasal sinus computed tomography (CT) using single volumetric 320-row multidetector CT technique. The low-dose protocol including tube voltage of 135 kV and tube current of 5 mAs was chosen based on results of the present phantom study. Forty-six patients were assigned to control group with factory standard settings (120 kVp, 75 mAs), and 46 patients were assigned to study group and underwent noncontrast CT of paranasal sinus with low-dose protocol using single volumetric 320-row multidetector CT device. Objective and subjective image qualities were performed. Effective radiation dose calculated for control group scans was 0.45 (SD, 0.39) mSv. It was 0.038 (SD, 0.004) mSv for study group scans. The effective radiation dose of study group was statistically significant lower than control group (P < 0.001). Noncontrast paranasal sinus CT imaging can be performed at very low radiation exposure maintaining high image quality with 135 kVp and 5 mAs.