Paranasal sinus imaging

Nasal endoscopy: What have we been missing?

Despite the widespread adoption of nasal endoscopy (NE) in the evaluation of sinonasal disease, its diagnostic potential may still be underutilized. Developments in endoscopic technology have led to significant improvements in video quality and maneuverability. However, there is concern that NE continues to be used primarily for the identification of gross pathology, with relative neglect of more subtle findings such as surface features of inflammation and mucus. With fewer technical limitations to perceive these abnormalities, there is potential to greatly improve the diagnostic value of NE. The reader is herein asked to consider several important visual nuances encountered during NE, with the hope that this engenders an appreciation of the versatility of NE as a diagnostic tool.

Headaches due to Nasal and Paranasal Sinus Disease

Headache and rhinosinusitis are 2 of the most common conditions seen in clinical practice. Consider sinusitis in those with new-onset headache, along with nasal congestion, maxillary tooth discomfort, anosmia, cough, or fever. Most chronic and recurring headaches, especially if migraine features are present, are not due to sinus disease, with the possible exception of rhinogenic headache due to nasal contact points. Nasal endoscopy and neuroimaging with computed tomography or MRI can confirm diagnosis and guide treatment with antibiotics, adjuvant therapies and surgery.

Evaluation of Anatomical Variations of the Maxillary Sinus in Patients With and Without Mucous Retention Cyst

Objectives: Mucous retention cyst (MRC) is a benign and self-limited lesion that can be caused by many risk factors, including anatomical variations of the sinonasal region. This study aims to investigate the relationship between anatomical variations and the presence of MRC. Materials and Methods: In total, 2109 sinonasal cone beam computed tomography images were evaluated for the presence of MRC, and the sinonasal anatomical regions such as the osteomeatal complex (OMC), infundibulum length, ostium height, the diameter of the ostium, the presence of accessory ostium, concha bullosa, and mucosal thickening of the maxillary sinuses. Shapiro-Wilk normality test, independent sample t-test, and chi-square test were used for statistical analysis, and P < .05 was considered significant. Results: The prevalence of MRC was 119 (5.6%) cases. The average diameter of the ostium in cases with and without MRC was 0.49 ± 0.41 mm and 0.99 ± 0.76 mm, respectively, which showed a significant inverse relationship(P < .001). A significant relationship was found between the septum deviation, the ostium height, the concha bullosa, and the accessory ostium with the presence of MRC (P < .001). Conclusions: Sinonasal anatomical variations such as ostium diameter, ostium height, septal deviation, the presence of accessory ostium, and concha bullosa can cause MRC development, and considering that surgery may be necessary in some cases; this could be of great importance to clinicians and surgeons for treatment and prevention of development or recurrence of these pseudocysts in patients.

Headache and rhinosinusitis: A review

PURPOSE OF REVIEW

To explain our current understanding of headache attributed to rhinosinusitis, an often inappropriately diagnosed secondary headache.

RECENT FINDINGS

Recent studies have shown that headache attributed to rhinosinusitis is often over-diagnosed in patients who actually have primary headache disorders, most commonly migraine. Failure to recognize and treat rhinosinusitis, however, can have devastating consequences. Abnormalities of the sinuses may also be treatable by surgical means, which may provide headache relief in appropriately selected patients.

SUMMARY

It is important for the practicing physician to understand how rhinosinusitis fits into the differential diagnosis of headache, both to avoid overdiagnosis in patients with primary headache, and to avoid underdiagnosis in patients with serious sinus disease.

Nontraumatic emergencies of inflammatory paranasal sinus disease

Inflammatory disease of the paranasal sinuses is extremely common and the course is often innocuous. However, when extrasinus spread of disease occurs life-threatening complications can arise. Intraorbital and intracranial involvement can progress rapidly either by hematogenous spread or in the case of fungal sinusitis via angioinvasion. An understanding of anatomy and appropriate imaging protocols is critical when these complications arise. The knowledge of imaging features of the different disease processes and prompt diagnosis is essential to improve patient outcomes and positively impact patient care.

Role of Concha Bullosa in Chronic Rhinosinusitis

Concha bullosa is one of the most common anatomical variant found in the patients of chronic rhinosinusitis. To study the role of concha bullosa in patients of chronic rhinosinusitis a prospective cross sectional study was done comprising of 60 patients who were having symptoms of sinusitis for more than 12 weeks. These were evaluated with the help of nasal endoscope and CT scan. DNS and concha bullosa are the most common anatomical variant seen in the patients of chronic rhinosinusitis with percentage being 88.3% and 76.6% respectively. Patients with deviated nasal septum and large concha bullosa (bulbous and extensive) were associated with higher incidence of ostiomeatal complex obstruction. There seems a strong relationship between unilateral concha bullosa and contralateral deviated nasal septum in development of chronic rhinosinusitis. (1) To find out the percentage and role of concha bullosa in patients of chronic rhinosinusitis. (2) To screen the patients of chronic rhinosinusitis for concha bullosa. (3) To do the nasal endoscopy and CT scan of the screened patients.

STUDY DESIGN

cross sectional study.

SAMPLE SIZE

60.

INCLUSION CRITERIA

all patients of chronic rhinosinusitis.

EXCLUSION CRITERIA

patients with previous sinus surgeries, malignancy and acute cases of chronic rhinosinusitis.

Clinical Course of Acute Maxillary Sinusitis Documented by Sequential MRI Scanning

A prospective study was designed to assess clinical and mucosal changes that occur during resolution of acute maxillary sinusitis. Thirteen previously healthy subjects with symptoms of acute sinusitis and radiographic opacification of at least one maxillary sinus were entered into the study and treated with amoxicillin/clavulinate potassium. Assessment of clinical symptoms, clinical examination, and magnetic resonance imaging (MRI) of the maxillary sinuses were performed at baseline and at days 3, 7, 10, 14, 21, 28 and 56 after initiation of therapy. The T2 values from the MRI scans were analyzed to approximate the more viscous and more fluid-like components of the maxillary sinus contents. After three days of antibiotic therapy, there was marked improvement in facial tenderness, thickness of nasal discharge, volume of nasal discharge, headache, and nasal congestion. Ten to 14 days of treatment were required, however, for improvement in nasal patency. MRI analysis of the volume percentage of air in the involved sinuses showed that by 10 days, only half of the opacification (fluid and thickened mucosa) had resolved. By 56 days, the sinuses were only about 80% aerated. This improvement was attributed mainly to resolution of the more fluid-like component. This study shows that: (1) tissue/fluid changes in sinusitis can be followed with MRI, and (2) although treatment of acute maxillary sinusitis generally results in clinical resolution of symptoms within one week, mucosal changes can persist for 8 weeks or more.

Role of Anatomic variations of Uncinate Process in Frontal Sinusitis

The osteomeatal complex plays an important role in the development of Chronic rhinosinusitis. The ethmoidal infundibulum is bordered medially by the uncinate process, and the anatomic relationship between the ethmoidal infundibulum and the frontal recess may depend upon the types of attachment of the uncinate process. The osteomeatal complex is the main area targeted in chronic rhinosinusitis and within it uncinate process is the first anatomical structure encountered. The aim of this study was to evaluate the types of attachment of the uncinate process and its implications in the development of sinus inflammation. The significance of anatomical variations of uncinate process in chronic sinusitis were evaluated. A prospective CT scan study on 64 patients of chronic sinusitis (128 uncinate processes) was done. The results were tabulated and analyzed using Statistical Package for Social Science 16.0. Type I superior attachment of uncinate process into the lamina papyracea was the most common variety in all ages and both sexes and a statistically significant association between Type 1 Uncinate process and frontal sinusitis was found. (P < 0.05). The superior attachment of uncinate process alters the frontal sinus drainage and causes the frontal sinusitis.

Study of Anatomical Variations on CT in Chronic Sinusitis

This is a prospective cross sectional study comprising of 85 patients who were having symptoms of sinusitis for more than 12 weeks which were evaluated with the help of nasal endoscopy and computed tomography scan to screen the patients of chronic-rhinosinusitis for various anatomical variants and to find their percentage. The most common variant found to be deviated nasal septum being 88.2 % followed by concha bullosa being 76.4 %, paradoxical middle turbinate 9 %, agger nasi in 7 %.

Endoscopic and computed tomographic evaluation of influence of nasal septal deviation on lateral wall of nose and its relation to sinus diseases

To correlate symptoms of deviated nasal septum (DNS) and chronic rhinosinusitis with the findings of nasal endoscopy and computed tomographic (CT) imaging. To evaluate the influence of degree of septal angle deviation on the severity of lateral nasal wall abnormalities. A prospective study was conducted on 67 patients with clinical evidence of DNS and chronic sinusitis attending ENT OPD between January 2012 and September 2013. All these patients underwent nasal endoscopy and CT scan PNS coronal sections. Direction and degree of DNS was recorded. Range of sinus mucosal thickening on CT scan films was also recorded. Chronic sinusitis is common in the age group between 21 and 40 years (50.74 %) with male preponderance (55.22 %), chief symptoms being nasal obstruction (86.56 %), headache (73.13 %) and nasal discharge (52.23 %). Left sided DNS is more common (64.17 %). Most of the patients have moderate DNS, i.e. 6°-10° (56.7 %), followed by severe (22.4 %) and then mild (20.9 %). DNS results in compensatory structural changes in the turbinates and/or lateral nasal wall which causes ostiomeatal complex (OMC) obstruction resulting in sinusitis. Contralateral concha bullosa and ethmoid bulla prominence was noted. Maxillary sinus is most commonly affected sinus (73.13 %). Patients with increasing septal angles were associated with a higher incidence of maxillary sinus mucosal changes (p < 0.05). Present study reemphasized the concept that septal deviation causes obstruction at OMC which results in an increased incidence and severity of bilateral chronic sinus disease.

Headaches caused by nasal and paranasal sinus disease

Headache and rhinosinusitis are 2 of the most common conditions seen in clinical practice. In general, chronic and disabling headaches, especially if migraine features are present, are not due to sinus abnormalities. In suspected cases of bacterial sinusitis, computed tomography and magnetic resonance imaging are both effective in demonstrating the infection. Although most cases of sinusitis are fairly easy to diagnose, sphenoid sinusitis may be overlooked, and can present with progressive or thunderclap headache in adults. Contact-point headache should be considered in patients with focal headaches and a contact point on the lateral nasal wall.

Anatomic variations of the bone in sinonasal C.T

Coronal plane Computed Tomographic (C.T) Scanning of paranasal sinuses is importannt as a preoperative evaluation tool and providing a road map for Functional Endoscopic Sinus Surgrey. The present study wea crried out on 61 patients of chronic sinusitis who underwent C.T. Scan of paranalal sinus, (coronal section) prior to Functional Endoscopic Sinus Surgery.The incidence of anatomical variations of the bone such as Agger nasi cells, Middle turbinate pneumatisation, Heller's Cells,Paradoxically curved middle turbinate, Deviated septum and Uncinate process variations, etc. were investigated in each C.T.Scan. Mucosal abnormalities in each paranasal sinus were also reported.The purpose of this investigation was to determine the background prevalence of bony anatomical variations and mucosal abnormalities of paranasal sinuses and assess the possile pathogenecity of these findings in patients undergoing evalation for Functional Endoscopic Sinus Surgery.

Diagnosis of chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a rather common disease in children, but its symptoms are often subtle and non-specific and this may result in overlooking a correct diagnosis. In turn, a missed diagnosis of CRS prevents a correct management to be performed and is associated with uneffective investigations and improper treatments. Actually, when CRS symptoms, which are mainly nasal congestion and obstruction, nasal discharge, facial pain, cough, and halitosis, are correctly assessed, the clinical diagnosis of CRS may be achieved, and confirmation may be obtained by imaging criteria or nasal fibroendoscopy. In imaging, computed tomography (CT) is the first choice technique for the evaluation of CRS and is able to provide an anatomic road map when surgery is required. Magnetic resonance imaging (MRI) of the sinuses, orbits, and brain should be performed whenever extensive or multiple complications of sinusitis are suspected. Also for middle ear disorders, CT is the first choice because it detects opacification of the middle ear cavity and mastoid cells, presence of fluids or debris, and allows the ossicular chain and the cortical bone of the mastoid to be evaluated. Another important diagnostic issue is the need to look for disorders that are frequently associated with CRS, such as obstructive sleep apnea syndrome (OSAS), that has some recognized risk factors in adenotonsillar hypertrophy, craniofacial anomalies, obesity, and neuromuscular disorders. Other associated disorders requiring investigation are recurrent or persistent otitis media and difficult asthma.

Radiographic density profiles link frontal and anterior ethmoid sinuses behavior in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) may occur through heterogeneous disease processes. It is possible that more than 1 inflammatory process underlies CRS in any given patient. If so, heterogeneity in processes may be a function of the spatial organization of the paranasal sinuses. Density characteristics of sinus opacities on computed tomography (CT) scans offer insight into the nature of sinus opacities and disease, in general, and may thus be used to detect spatial heterogeneity of sinus disease within a given patient.

METHODS

The study was a retrospective chart review of CRS patients with available sinus CT scans. Radiographic density profiles of sinus opacities were assessed by raw measures of densities (in Hounsfield units [HU]). Radiographic density profiles of the different affected sinuses were compared to each other, checked for correlation, and finally, checked for evidence of clustering using a principal component analysis.

RESULTS

Frontal sinus opacities appear to be more heterogeneous, with both higher and lower density components than other sinuses. There was strong correlation between the radiographic density profiles of opacities in the frontal, anterior ethmoid, and sphenoid sinuses (p < 0.001). However, on principal component analysis the radiographic density characteristics of the opacities of the frontal and anterior ethmoid sinuses appeared to cluster together more than the other sinuses.

CONCLUSION

Radiographic properties of sinus opacities suggest the nature of sinus opacities are related not only to some common underlying pathology but also to factors related to the specific sinus as well as other spatially close affected sinuses. This suggests an anatomic orientation for sinus pathophysiology in CRS.

Multiplanar computed tomographic analysis of the frontal recess region in Chinese subjects without frontal sinus disease symptoms

The purposes of this study were to determine the prevalence of frontal-ethmoidal cells and to evaluate variation in the superior attachment of the uncinate process in Chinese subjects. 202 normal Chinese subjects (404 sides) underwent spiral computed tomography and multiplanar reconstruction images were evaluated. Agger nasi cells showed a prevalence of 94.1%. Of all the frontal cells identified in 159 sides (39.6%) of frontal recesses, the prevalence of type I, type II and type III cells was 24.4, 7.0 and 8.2%, respectively. Suprabullar, frontal bullar and interfrontal septal cells were identified in 148 sides (36.6%), 36 sides (9.0%) and 25 subjects (12.4%), respectively. 244 uncinate processes (60.4%) had 1 superior attachment and the remainder (39.6%) had 2 superior attachments. The prevalence of terminal recesses was 89.1%. Our results characterized normal frontal recess pneumatization patterns in Chinese subjects. That, together with variation in the superior attachment of the uncinate process, emphasized the role of agger nasi cells and the uncinate process in endoscopic frontal sinus surgery.

CT and MRI features in Bipolaris fungal sinusitis

Bipolaris is an increasingly recognized cause of fungal sinusitis. Reports of imaging features are sparse. Our purpose was to review the imaging features in patients with Bipolaris fungal sinusitis. A review of our data showed seven patients with culture-proven Bipolaris fungal sinusitis. Computed tomography of the paranasal sinuses in all the patients and MRI in five patients were analysed for the location, nature, extent of the disease and density/signal characteristics on CT/MRI. The sphenoid and posterior ethmoid sinuses were most often involved (six of seven), followed by the anterior ethmoid sinus (five of seven), frontal sinus (four of seven) and maxillary sinus (three of seven) involvement. Five of seven cases had bilateral disease. Secretions were seen to fill the sinus and were expansile in nature in six of seven cases. Bony erosion was noted in all the patients. Air-fluid levels and bony sclerosis were rarely seen. Computed tomography showed central hyperdensity in all the cases. In the corresponding MR images (n = 5), the sinus contents appeared hyperintense on T1-weighted images and hypointense on T2-weighted images. Extension into the nasal cavity was found in six of seven cases. Five of seven cases had intracranial (extradural) spread. Intraorbital extension was seen in three of seven cases, with associated optic nerve compression in two. All the patients responded to surgical debridement, and systemic antifungal therapy was not required. Bipolaris fungal sinusitis typically presents with an allergic fungal sinusitis picture with expansile sinus opacification and bony erosions. There is central hyperdensity on CT scan, which appears hyperintense on T1-weighted and hypointense on T2-weighted MR images.

Radiological imaging of inflammatory lesions in the nasal cavity and paranasal sinuses

Paranasal sinus development and pneumatisation variants are described, and rhinosinusitis and different patterns of inflammatory sinonasal diseases are reviewed. Other inflammatory sinonasal diseases, e.g., fungal sinusitis, mucocele, pyocele and sinonasal manifestations in systemic diseases, are briefly described. Computed tomography (CT) is the primary modality in diagnosing and mapping suspected inflammatory sinonasal disease. Magnetic resonance (MR) imaging is complementary to CT if fungal sinusitis, pyocele or malignancy are suspected.

Morphometric examination of the paranasal sinuses and mastoid air cells using computed tomography

BACKGROUND

The paranasal sinuses and mastoid air cells vary considerably in size and shape from person to person. The main structures are pneumatic. In this study, we investigated the relationship between right and left sides and evaluated the volume changes according to age and sex.

METHODS

Of all patients attending the radiology department, 91 cases without paranasal sinuses and mastoid air cells pathology (i.e., inflammation, operation or trauma) were selected for evaluation. Axial computed tomography (CT) scans were obtained for both paranasal sinuses and temporal bones. In all scans, the volumes of each area (maxillary sinus, frontal sinus, sphenoid sinus and mastoid air cell) were calculated and analyzed statistically.

RESULTS

The volumes of paranasal sinuses and mastoid air cells increased with age and women had a lower mean volume. There was a positive correlation between right-left and ipsilateral structures (paranasal sinuses and mastoid air cells).

CONCLUSIONS

These results are helpful in understanding the normal and pathological conditions of the paranasal sinuses and the mastoid air cells.

Imaging of neoplasms of the paranasal sinuses

The assessment of sinonasal malignancies requires a multidisciplinary team approach.Advances in pretherapeutic imaging have significantly contributed to the managementof sinonasal tumors. CT and MR imaging play complementary roles in the assess-mentand staging of these malignancies by determining the presence or absence of exten-sionof disease into the skull base and its foramina, the orbit, and the intracranial compartment.

Headaches due to nasal and paranasal sinus disease

Sinus infections are much less common today than they were in the preantibiotic era, but they still are overdiagnosed. Acute sinusitis, a relatively uncommon cause of headache, is the result of infection of one or more of the cranial sinuses. Acute sinusitis usually is characterized by purulent discharge in the nasal passages and a pain profile determined by the site of infection. Sinusitis is overdiagnosed as a cause of headache because of the belief that pain over the sinuses must be related to the sinuses. In fact, frontal head pain more often is caused by migraine and tension-type headache. It should not follow that if a patient fails to respond to treatment for migraine and tension-type headache one should reconsider the diagnosis of sinus disease. Whether or not nasal obstruction can lead to chronic headache is controversial. Paradoxically, sinus disease also tends to be underdiagnosed, as sphenoid sinus infection frequently is missed.

Evaluation of the pathophysiology of odontogenic maxillary sinusitis using bone scintigraphy

The inflammatory changes in the maxillary sinus mucosa and wall (mucosal and bony lesions) were evaluated to identify the pathophysiology of odontogenic maxillary sinusitis. Out of 80 patients who underwent CT, 32 patients were examined using single photon emission computerized tomography (SPECT) bone scintigraphy (bone SPECT) with 99mTc-hydroxymethylene-diphosphonate. Mucosal and bony lesions were evaluated morphologically on both images. SPECT data were used to assess the bone activity by calculating the count ratios of the causative alveolar process over the cervical vertebrae. The relationships with clinical symptoms, mucosal changes around the maxillary ostium (ostial lesions), and radiolucencies around the causal teeth (periapical lesions) were assessed. Bone SPECT showing the causal site was valuable for aiding a definitive diagnosis. Mucosal lesions tended to exceed bony lesions horizontally and vertically. Bony lesions tended to extend posteriorly and then anteriorly. The vertical extent of mucosal lesions and the horizontal and vertical extent of bony lesions were correlated with the presence of facial symptoms, ostial lesions, and periapical lesions. Bone activity was significantly correlated with the horizontal and vertical extent of mucosal lesions, horizontal extent of bony lesions, and presence of infraorbital symptoms, ostial lesions, and periapical lesions. Bone activity caused by alveolitis affects the pathophysiology of this disease.

Imaging of neoplasms of the paranasal sinuses

The assessment of sinonasal malignancies requires a multidisciplinary team approach. Advances in pretherapeutic imaging have significantly contributed to the management of sinonasal tumors. CT and MR imaging play complementary roles in the assessment and staging of these malignancies by determining the presence or absence of extension of disease into the skull base and its foramina, the orbit, and the intracranial compartment.

Evaluation of odontogenic maxillary sinusitis after conservative therapy using CT and bone SPECT

Fifteen patients with odontogenic maxillary sinusitis examined using computed tomography (CT) and single photon emission computed tomography bone scintigraphy (bone SPECT) were reviewed. The changes in bone activity associated with causative maxillary alveolitis, evaluated by bone SPECT, before and after conservative therapy were correlated with the pathologic changes in the maxillary sinus mucosa and ostium demonstrated on CT images following conservative therapy. This combination of imaging methods is valuable for predicting the prognosis and selecting appropriate treatments for the disease.

Chronic sinusitis in severe asthma is related to sputum eosinophilia

BACKGROUND

Chronic rhinosinusitis and asthma are conditions that frequently coexist, particularly in severe asthma. The precise mechanism of the relationship between upper and lower airway inflammation is still a matter of debate. We hypothesized that the extent of inflammation in the nasal mucosa is related to lung function and inflammation in the bronchial mucosa in patients with severe asthma.

OBJECTIVE

We sought to investigate the relationship between sinonasal inflammation as assessed on computed tomography (CT) scanning, lung function, sputum eosinophilia, and nitric oxide (NO) in exhaled air in patients with severe asthma.

METHODS

Eighty-nine nonsmoking outpatients with severe asthma (29 men and 60 women; mean age 45 years; age range, 18-74 years) were included in this study. CT scans were scored (0-30) by a blinded investigator using a validated method. Lung function, NO in exhaled air, and sputum eosinophils were measured by using standard procedures.

RESULTS

CT scans showed abnormalities in 84% of patients. Extensive sinus disease (score 12-30) was found in 24% of patients. There was a significant positive correlation between CT scores and eosinophils in peripheral blood (R(s) = 0.46) and induced sputum (R(s) = 0.40) and level of exhaled NO (R(s) = 0.45, P <.01). CT scores were also positively related to functional residual capacity and inversely related to diffusion capacity, particularly in patients with adult-onset asthma (R(s) = 0.47 and R(s) = -0.53, respectively).

CONCLUSIONS

The results of this study show a direct relationship between sinonasal mucosa thickness and bronchial inflammation in severe asthma, particularly in patients with adult-onset disease. Whether sinus disease directly affects the intensity of bronchial inflammation is still an unanswered question.

Imaging of the olfactory system

The olfactory system consists of the primary olfactory nerves in the nasal cavity, the olfactory bulbs and tracts, and numerous intracranial connections and pathways. Diseases affecting the sense of smell can be located both extracranially and intracranially. Many sinonasal inflammatory and neoplastic processes may affect olfaction. Intracranially congenital, traumatic, and neurodegenerative disorders are usually to blame for olfactory dysfunction. The breadth of diseases that affect the sense of smell is astounding, yet the imaging ramifications have barely been explored.

Diagnostic value of spect bone scintigraphy for odontogenic maxillary sinusitis

PURPOSE

The aim of this study was to assess the diagnostic value of bone SPECT for odontogenic maxillary sinusitis and bone activity in the alveolar process to clarify the pathophysiologic nature of the disease.

MATERIALS AND METHODS

Computed tomography and bone SPECT with Tc-99m HMDP were performed in 28 patients with odontogenic maxillary sinusitis. Based on the findings of the computed tomographic images, the inflammatory changes in the maxillary sinus mucosa (mucosal lesions) were evaluated horizontally and vertically. For the initial diagnosis, visualization of the causative site by bone SPECT was compared with conventional radiographic and planar findings. SPECT data were used to assess bone activity by calculating the mean count ratios of the alveolar process over the cervical vertebrae. The relation of bone activity to the structure of the mucosal lesions, the presence of clinical symptoms, mucosal changes around the maxillary ostium (ostial lesions), and conventional radiolucent images around the causative teeth (periapical lesions) were assessed.

RESULTS

Identification of the causative site was sufficiently specific in bone SPECT images. Bone activity was significantly correlated with the structure of the mucosal lesions, both horizontally and vertically, and with the presence of infraorbital symptoms, ostial lesions, and periapical lesions.

CONCLUSIONS

It is important to view odontogenic maxillary sinusitis as a bone disease in which the bone activity associated with alveolar osteitis affects the pathophysiologic nature of the disease. Bone SPECT is valuable to make a more precise diagnosis, thereby allowing more appropriate treatment of the disease.

Extent of pathological changes in the paranasal sinuses of patients with cystic fibrosis: CT analysis

The aim of the study was to define the characteristic changes revealed by computed tomography (CT) examination of the paranasal sinuses in patients with cystic fibrosis (CF). The group of 30 CF patients was evaluated in the outpatient clinic of the Department of Otorhinolaryngology, Medical University of Warsaw, from 1996 to 1998. The control group consisted of 30 patients with chronic rhinosinusitis (CRS). CT scans were obtained from both groups of patients, and findings revealed more advanced pathological changes in the CF than CRS group. The extensive inflammatory process observed in CT scans of CF patients resulted in the impairment of frontal and maxillary sinus development, destruction of bony structures, and medial projection of the lateral nasal wall.

Complementary role of MR imaging of ethmomaxillary sinus disease depicted at CT in cystic fibrosis

PURPOSE

To assess whether MR imaging can improve characterization of ethmomaxillary opacification diagnosed at CT in patients with cystic fibrosis (CF) in order to select patients that may benefit from functional endoscopic sinus surgery (FESS).

MATERIAL AND METHODS

Sixty-two CF patients (26 females and 36 males) aged 4-50 years (median 20 years) with ethmomaxillary sinus disease at CT underwent MR examination of the paranasal sinuses (coronal T1 and STIR sequences). FESS had been performed in 28 of the patients prior to this study. MR signal intensities were interpreted as mucosal thickening or infectious material, according to a previous study.

RESULTS

Three major maxillary sinus MR patterns could be distinguished: Air-filled, oval-shaped pus-filled, and streaky-shaped pus-filled sinus lumen. For air-filled maxillary sinuses with mucosal thickening, CT and MR imaging were diagnostically equivalent. Where CT showed homogeneous opacification of the maxillary sinuses, MR imaging differentiated between thickened mucosa and pus-filled areas. Patients who had undergone FESS most commonly had air-filled or streaky-shaped pus-filled maxillary sinus lumen. In non-operated patients oval-shaped pus-filled sinus lumen was most common and could occur without ethmoid disease.

CONCLUSION

MR imaging of the paranasal sinuses can differentiate between infectious material and thickened mucosa and should be used to select CF patients with pus-filled areas that can be eradicated with FESS.

Septal deviation and chronic sinus disease

The introduction of computerized tomography in the identification of sinonasal pathology and associated anatomic variants has contributed to a greater understanding of the factors leading to ostiomeatal complex (OMC) obstruction and chronic sinus disease. The OMC and paranasal sinus regions were prospectively evaluated in 150 consecutive patients as a function of the degree of nasal septal deviation and compared with matched controls. These data were correlated with paranasal sinus disease, lateral nasal wall findings, and middle turbinate abnormalities. An increased incidence and severity of bilateral chronic sinus disease was present with increasing septal deviations (p < 0.05). Similarly, patients with increasing nasal septum deviations were noted to have a higher incidence of OMC obstruction (p < 0.05). Ostiomeatal complex obstruction in the direction of septal angulation was associated with nasal septal deformity; however, contralateral OMC obstruction was associated with middle turbinate and lateral nasal wall abnormalities (p < 0.05). The evaluation of the degree of septal angulation has helped better understand the factors contributing to chronic sinus disease and OMC obstruction.

Fever in the ICU

Fever is a common problem in ICU patients. The presence of fever frequently results in the performance of diagnostic tests and procedures that significantly increase medical costs and expose the patient to unnecessary invasive diagnostic procedures and the inappropriate use of antibiotics. ICU patients frequently have multiple infectious and noninfectious causes of fever, necessitating a systematic and comprehensive diagnostic approach. Pneumonia, sinusitis, and blood stream infection are the most common infectious causes of fever. The urinary tract is unimportant in most ICU patients as a primary source of infection. Fever is a basic evolutionary response to infection, is an important host defense mechanism and, in the majority of patients, does not require treatment in itself. This article reviews the common infectious and noninfectious causes of fever in ICU patients and outlines a rational approach to the management of this problem.

Perennial allergic rhinitis and chronic sinusitis: correlation with rhinologic risk factors

BACKGROUND

The reported association of allergy and sinusitis varies greatly between study, and the exact role of allergy in predisposing to sinusitis is not clear. We attempted to determine whether patients with perennial allergic rhinitis are at greater risk of developing sinusitis with respect to a control group, and to determine whether there is a correlation between rhinomanometry, endoscopy, and nasal swab, and computed tomography (CT) findings.

METHODS

Forty adult patients with perennial allergic rhinitis underwent CT scans of the paranasal sinuses, and the results were then compared to CTs of the paranasal sinuses of 30 control subjects. All allergic patients underwent nasal endoscopy, nasal swab, and active anterior rhinomanometry, and the results were studied in relation to the CT findings.

RESULTS

We found sinusitis in 67.5% of the allergic patients and in 33.4% of the controls, with a statistically significant difference between the two groups (P = 0.017). Twenty-three patients had a positive nasal swab; 22 showed increased nasal resistance on rhinomanometry, and 36 had positive endoscopy, but the association of CT findings with endoscopy, rhinomanometry, or nasal swab was not statistically significant (P = 0.583, P = 1.00, P = 0.506, respectively).

CONCLUSIONS

Allergic rhinitis is often associated with sinusitis, but the underlying mechanism has yet to be determined. Evidently, factors other than classical pathogen growth and mechanical factors, such as the association of the various factors and immunologic mechanisms, may contribute to the pathogenesis of chronic sinusitis in allergic patients.

Relative value of MR imaging as compared with CT in the diagnosis of inflammatory paranasal sinus disease

PURPOSE

To evaluate the relative value of magnetic resonance (MR) imaging versus computed tomography (CT) in the diagnosis of inflammatory paranasal sinus disease.

MATERIALS AND METHODS

In 30 patients suspected of having or known to have inflammation of the paranasal sinuses, both coronal CT and coronal T1-weighted, three-dimensional, gradient-echo MR imaging of the paranasal sinuses were performed. Visualization of anatomic details, kind and extent of inflammatory disease, and artifacts from dental work were scored. The scores were compared by using the Wilcoxon matched pairs signed rank test. Interexamination agreement between the two methods was calculated by using a kappa analysis.

RESULTS

Most bone structures of the infundibular complex were significantly better visualized at CT than at MR imaging. Orbital and brain anatomy were visualized better at MR imaging than at CT. No artifacts from dental work occurred in diagnostically relevant regions at MR imaging. There was a substantial to almost perfect agreement between CT and MR imaging for every kind and extent of the disease except for mucosal thickening in the maxillary and frontal sinuses, in the nasal cavity, and in the infundibulum.

CONCLUSION

CT is superior to MR imaging in the depiction of fine bony details and anatomic variants and thus is superior to MR imaging in helping plan functional endoscopic sinus surgery. However, there are patient groups in which MR imaging can be used as a primary tool in screening for sinusitis.

Recognition and management of sinusitis

Acute sinusitis frequently follows upper respiratory tract infections. Patients complain of headache, facial pain, fever and purulent rhinorrhoea. Diagnosis is based upon the symptoms, and treatment comprises symptomatic relief with analgesics, topical or systemic decongestants and steam inhalation. If indicated, antibiotics should be given for an adequate period of time. Patients with chronic sinusitis complain of a combination of nasal obstruction, rhinorrhoea and postnasal drip associated with intermittent facial pain, with symptoms persisting for 3 months or more. Predisposition to the condition may be caused by rhinitis (allergic or nonallergic) and anatomical variants. Failure of mucociliary transport and sinus ostial obstruction leads to mucosal oedema, mucous hypersecretion and chronic infection. Current treatment aims are to control rhinitis and improve ventilation and function of the sinuses. Rhinitis may be controlled with the long term use of topical corticosteroids, mast cell stabilisers or antihistamines, either alone or in combination. Secretions may be cleared with steam inhalation and/or saline nasal douching. Failure to control chronic sinusitis with medical treatment may indicate surgery. The aim of surgery is to improve ventilation and facilitate drainage of the sinuses, allowing the restoration of normal function. Removal of nasal polyps, reduction of inferior turbinates or septal straightening may be all that is required. Some patients will need endoscopic ethmoidectomy and middle meatal antrostomy. Improved ventilation in the ethmoid infundibulum may help to resolve disease in maxillary and frontal sinuses. Medical treatment of underlying rhinitis will need to be continued postoperatively, often in the long term, while special consideration needs to be paid to sinusitis in children, in relation to dental disease and in the immunosuppressed. Complications of acute and chronic sinusitis include intraorbital and intracranial sepsis. These potentially lethal complications need urgent evaluation with high resolution computerised tomography (CT) scanning, intravenous administration of broad spectrum antibiotics (including anaerobic and microaerophilic cover) and urgent surgical drainage as appropriate.

Surgical management of rhinosinusitis

Rhinosinusitis, an inflammatory disease involving the nasal cavity and paranasal sinuses, affects millions of individuals and its costs run into the billions of dollars. The development of rigid nasal telescopes has revolutionized the diagnosis and treatment of this disease. Recent endoscopic evaluations have identified certain key areas within the nasal cavity that, when inflamed, lead to sinus ostial obstruction and subsequent sinus infection. The telescope's increased visualization capabilities permits the physician to better target and individualize patient care and the techniques that have grown out of this new tool allow for a more physiologic approach to surgical treatment. The pathophysiology of rhinosinusitis and its medical treatments are considered. Indications for surgical management are reviewed, with attention to nontraditional or extended applications of endoscopic techniques. Preoperative evaluation, including nasal endoscopy and radiographic imaging, as well as surgical technique and postoperative care are discussed. Evaluation of outcomes from surgical treatment in appropriately selected patients have demonstrated the success of this technique.

MRI of hyperpolarized 3He gas in human paranasal sinuses

In this study, MRI of hyperpolarized 3He gas in human paranasal sinuses is presented. Helium images were obtained at 1.5 T, using a surface coil and a 2D, fast gradient-echo sequence with a nominal constant flip angle of 12 degrees. Coronal images of 20-mm thick slices were generated and compared with proton images of the corresponding sections. The images enable visualization of the paranasal sinuses and the nasal cavity, suggesting a potential use of this method not only in identifying the anatomical configuration of these pneumatic spaces, but also in assessing sinus ventilation.

Current indications and techniques in evaluating inflammatory disease and neoplasia of the sinonasal cavities

Imaging strategies of the sinonasal cavities have undergone extensive revision over the last 5-year period. The traditional imaging examination of the paranasal sinuses, plain film radiography, does reasonably well in diagnosing maxillary, frontal, and sphenoid sinusitis. However, it less reliable in depicting abnormalities in the ethmoid sinuses, the most common area first affected with inflammatory disease. Compared with sinus computed tomography (CT), plain films prove to be less specific and sensitive in depicting the extent of sinus abnormalities. One series plainly concluded that sinus radiographs were not reliable enough to be an integral part of the clinical decision process. The use of plain radiographs of the sinuses has clearly been reduced by medical cost-containment concerns, replacement by superior techniques, and by clear weaknesses of the modality. Although it is inexpensive and easily accessible, the low sensitivities and inaccuracies of plain film radiography have resulted in the current use of CT and high-field-strength (1.5 Tesla) magnetic resonance imaging (MRI). By using this cross-sectional imaging, we now visualize directly the pathologic conditions within the sinuses, as well as the normal anatomy. We discuss current use of diagnostic imaging in the evaluation of patients with nasosinusoidal complaints (most commonly resulting from acute and chronic inflammatory disease), with complications of sinonasal inflammatory disease, and with suspected/documented neoplasia. In addition to developing an imaging algorithm to provide the information affecting clinical decision making, we detail the specific imaging techniques necessary accurately to obtain that information. We also review the specific concerns about imaging patients in the intensive care unit and touch on several emerging imaging techniques. The imaging workup in pediatric patients and patients with congenital anomalies is beyond the scope of this review.

Maxillary sinus inflammatory disease: ultrasound compared to computed tomography

Fifty-six patients (age range, 15-79 yr, average, 37.0+/-18.5 yr), with a clinical and/or radiological diagnosis of acute maxillary sinusitis, were prospectively studied with ultrasound (US) and computed tomography (CT). The imaging finding which supported the diagnosis of acute sinusitis with US was the identification of the hyperechoic posterior antral wall through the hypoechoic inflammation. The findings were compared to CT (3 mm axial sections). The sensitivity of US for maxillary sinus disease was found to be 66.7% and the specificity was 94.9%, which were similar to the plain film ones (65.2 and 96.8%, respectively). The results of the present study suggest US as the method of first choice for acute sinusitis of the maxillary antra, particularly for children and pregnant women.

Imaging of paranasal sinus disease

Imaging plays an important role in the management of paranasal sinus disease in the pediatric population. An understanding of the advantages and disadvantages of available modalities enables the clinician to best utilize imaging resources.

The anatomic relevance of the Haller cell in sinusitis

In current theories of sinusitis, obstruction at the ostiomeatal complex leads to localized inflammation and infection. Haller cells, an extension of ethmoid pneumatization along the maxillary antrum roof, have also been suggested as a causative factor in sinusitis because of their ability to cause narrowing of the infundibulum. Coronal CT scans were reviewed in 154 patients to evaluate the role of Haller cells in sinusitis. Haller cells were present in 34% of patients. The cells were graded as small, medium, or large, and correlated with radiologic evidence of sinusitis (e.g., mucosal thickening or opacification). A statistically significant increase in maxillary sinus mucosal disease was noted in patients with medium or large Haller cells (45.8%) versus those with small cells (28.9%, p < 0.05). Thus obstructive medium and large Haller cells may be an etiologic factor in sinusitis.

Clinical classification as a guide to treatment of sinusitis in children

Evaluation of all 153 children undergoing CT scan of the paranasal sinuses for recalcitrant sinusitis symptoms between January 1988 and July 1992 was performed. Clinical categorization into groups of patients presenting with chronic sinusitis (CS) and recurrent acute sinusitis (RAS) was based upon pattern of disease and presentation. Clinical symptoms and signs, radiological examination, treatment, and outcome were compared between these distinct clinical groups. Eighty-two (55%) children were categorized as RAS and 68 (45%) as CS. Children with CS presented more frequently with a persistent cough, purulent nasal discharge, immune deficiency, and more severe mucosal disease on CT than children with RAS. Medical therapy successfully controlled the symptoms of sinusitis in 79 (96%) with RAS versus 27 (40%) with CS. Surgery was performed in 44 children: 3 (3.6%) with RAS versus 41 (60%) with CS, p < 0.01. At a mean follow-up of 2.0 years, >80% of all the children were either asymptomatic or improved regardless of treatment modality. These data support the use of clinical classification as a guide to medical versus surgical therapy in children with sinusitis.

Coronal CT of the paranasal sinuses before and after functional endoscopic sinus surgery

Coronal CT of the paranasal sinuses and the ostiomeatal complex (OMC) was performed before and 12 months after bilateral functional endoscopic sinus surgery (FESS) in 30 patients with sinusitis and 12 patients with nasal polyposis. The extent of sinus mucosal thickening was graded, and the patency of the OMC was evaluated. After FESS, the percentage of open OMCs had increased from 42% to 83% in the sinusitis group, and from 8% to 45% in the polyposis group. There was only a small improvement in mucosal score in sinuses with opened OMC, so that the overall extent of sinus opacification before and after FESS was almost the same. Despite this, 91% of the patients reported clinical relief of symptoms. Preoperative coronal CT of the paranasal sinuses serves as an anatomical map for the surgeon, but there is no benefit of routine postoperative CT.