The "sinusogram", a real-time ultrasound sign of maxillary sinusitis

Multicenter Observational Study to Evaluate the Diagnostic Value of Sonography in Patients with Chronic Rhinosinusitis

(1) Background: Computed tomography (CT) is considered mandatory for assessing the extent of pathologies in the paranasal sinuses (PNS) in chronic rhinosinusitis (CRS). However, there are few evidence-based data on the value of ultrasound (US) in CRS. This multicenter approach aimed to compare diagnostic imaging modalities in relation to findings during surgery. (2) Methods: 127 patients with CRS were included in this prospective multicenter study. Patients received preoperative US and CT scans. The sensitivity and specificity of CT and US were extrapolated from intraoperative data. (3) Results: CT scans showed the highest sensitivity (97%) and specificity (67%) in assessing CRS. Sensitivities of B-scan US were significantly lower regarding the maxillary sinus (88%), the ethmoid sinus (53%), and the frontal sinus (45%). The highest overall sensitivity was observed for assessing the pathology of the maxillary sinus. (4) Conclusions: We observed high accuracy with CT, confirming its importance in preoperative imaging in CRS. Despite the high US expertise of all investigators and a standardized examination protocol, the validity of CT was significantly higher than US. Ultrasound of the PNS sinuses is applicable in everyday clinical practice but lacks diagnostic accuracy. Nevertheless, it might serve as a complementary hands-on screening tool to directly correlate the clinical findings in patients with PNS disease.

Ultrasonographic assessment of airway

Ultrasound is gaining increasing popularity among anesthesiologists as it is readily available and provides real-time imaging for various procedures. It is considered as a “visual stethoscope” of the anesthesiologist. After establishing its use in regional blocks and central venous catheter insertion, it is now finding increasing use in anticipation of difficult airway and securing and maintaining it. It has challenged the classical approach of clinical assessment of airway and allows more dynamic bedside assessment. This article attempts to briefly outline the role of ultrasound and its applications for airway management in patients.

Point-of-Care Sinus Ultrasound: Impact Within a Large Internal Medicine Clinic and Review of Technique

Outpatient diagnosis of acute bacterial sinusitis, using only traditional physical examination and clinical criteria, results in the overuse of antibiotics in patients with upper respiratory complaints. Point-of-care maxillary sinus ultrasound is easy to learn and quick to perform in a primary care clinic. The technique can reduce antibiotic prescribing by reassuring both patients and providers of the absence of fluid in the sinus, the hallmark of maxillary sinusitis. A review of the literature, description of technique, and results of sinus ultrasound implementation in a large internal medicine clinic are included.

[Ultrasound guided airway access]

Ultrasound has increasingly growing applications in anesthesia. This procedure has proven to be a novel, non-invasive and simple technique for the upper airway management, proving to be a useful tool, not only in the operating room but also in the intensive care unit and emergency department. Indeed, over the years mounting evidence has showed an increasing role of ultrasound in airway management. In this review, the authors will discuss the importance of ultrasound in the airway preoperative assessment as a way of detecting signs of difficult intubation or to define the type and/or size of the endotracheal tube as well as to help airway procedures such as endotracheal intubation, cricothyrotomy, percutaneous tracheal intubation, retrograde intubation as well as the criteria for extubation.

A new ultrasound sign in the diagnosis of pediatric maxillary sinusitis

Background: Computed tomography scans (CT scan) and X-rays are used to diagnose paediatric maxillary sinusitis. This study aimed at exploring the diagnostic value of the conventional and colour Doppler ultrasounds and their specific findings in cases of paediatric sinusitis. Methods: A total of 60 children diagnosed with sinusitis were included in this study. The conventional and colour Doppler ultrasounds of the sinus were performed on each of them. The symptoms that suggested increased blood flow to the sinuses were interpreted as positive findings on the colour Doppler ultrasound and were named "Ghasemi signs" for the purpose of this study. Such symptoms included unilateral artery bumps on the front artery, reduction of arterial resistive index (RI) to less than 0.5, and diameter of 2 mm or above for maxillary arteries. Sensitivity, specificity, and positive and negative predictive values, and accuracy of the conventional and colour Doppler ultrasounds were also calculated. Results: Compared to CT scan, the conventional ultrasound showed sensitivity and specificity of 73.4% and 100%, respectively. Sensitivity and specificity for the colour Doppler ultrasound were 89.36% and 100%, respectively. The maxillary artery diameter in normal and affected maxillary sinuses were, respectively, 2.4 mm (2.1-2.6, 95% CI) and 1.7 mm (1.6-1.9, 95% CI), with p<0.001. The RI of the affected sinuses were 0.47 (0.45-0.49, 95% CI), and those of the normal sinuses were 0.58 (0.54-0.61, 95% CI), with p<0.001. Conclusion: The findings of this study revealed that the conventional ultrasound agrees with the CT scans in the diagnosis of paediatric maxillary sinusitis. This diagnostic modality becomes even more valuable when the colour Doppler is used, particularly when considering the specific symptoms (Ghasemi signs) suggested by this study.

Potential role of ultrasound in anesthesia and intensive care

One of the most exiting recent technological advances in the field of anesthesia to track the region of interest is the introduction of anatomical evaluation by ultrasound imaging. Widespread use of this modality depends on its proven clinical efficacy, cost effectiveness, and practicality as it allows anesthesiologist to evaluate complex and varied anatomy prior to needle insertion. Sound used in medicine is not significantly transmitted by air or bone but through fluids which make up the larger part of soft tissues in the body. Ultrasound has been shown to offer excellent guidance for difficult venous access, epidural space identification in cases of difficult anatomy, delineating nerve plexuses for chronic nerve blocks, for regional anesthesia, and in transesophageal echocardiography for cardiac imaging with blood flows or in an otherwise high-risk patient where interventional procedure is required. It has special application to assess the narrowest diameter of the subglottic upper airway. A systemic literature search was performed in PubMed and the Cochrane library. The search strategy was set up using either single text word or combinations. We also included the studies where in these techniques were compared with conventional methods . Despite the initial excitement of this technique, ultrasound visualization is still indirect and images are subject to individual interpretation. It is gradually becoming routine in daily practice at our institution due to its reliability and safety. Though ultrasound is much safer, exposure in terms of intensity and time should be limited as far as possible, as high-energy ultrasound can cause heating and damage to tissues. In this review, we discuss established and future areas of ultrasound imaging and emphasize the use of B-mode ultrasound to improve the efficacy of interventional techniques. We have also illustrated potential uses with reference to cross-sectional B-mode images which visually represent a slice of tissues and are the easiest images for interpretation by clinicians.

Sonography for diagnosis of benign and malignant tumors of the nose and paranasal sinuses

OBJECTIVES

The purpose of this study was to demonstrate the reliability of sonography for diagnosis of nose and paranasal sinus tumors.

METHODS

Ninety-six consecutive patients with tumors underwent sonography and computed tomography (CT) before surgical treatment. Tumor detectability and imaging findings were evaluated independently and then compared with pathologic findings.

RESULTS

Of 96 tumors, 75 were detected by sonography, for a detectability rate of 78.1%; 93 tumors were detected by CT, for a detectability rate of 96.9%. By comparison, sonography showed a trend toward higher detectability of nasal vestibular tumors than CT (87.5% for sonography versus 50.0% for CT) and small lumps on the wing of the nose (78.8% for sonography versus 33.3% for CT). Among the sonographic features, boundary, shape, internal echo, calcification, bone invasion, vascular pattern, and cervical lymph node metastasis all had significantly positive correlations with malignancy (P < .05), but size did not (P = .324). In addition, the vascular resistive index for malignant tumors was significantly higher (mean ± SD, 0.66 ± 0.20) than the index for benign lesions (0.24 ± 0.30; P < .001). Moreover, the detection rate for grade 1-3 (small-large) blood flow in benign lesions was only 43.8%, whereas the rate for malignant tumors was 97.7% (P < .001).

CONCLUSIONS

The vascular pattern may be a promising predictive indicator for distinguishing benign and malignant tumors of the nose and paranasal sinuses. Consequently, sonography has high value for diagnosis of benign and malignant tumors of the nose and paranasal sinuses, especially for nasal vestibular tumors and small lumps on the wing of the nose.

Ultrasound of the airway

Currently, the role of ultrasound (US) in anaesthesia-related airway assessment and procedural interventions is encouraging, though it is still ill defined. US can visualise anatomical structures in the supraglottic, glottic and subglottic regions. The floor of the mouth can be visualised by both transcutaneous view of the neck and also by transoral or sublinguial views. However, imaging the epiglottis can be challenging as it is suspended in air. US may detect signs suggestive of difficult intubation, but the data are limited. Other possible applications in airway management include confirmation of correct endotracheal tube placement, prediction of post-extubation stridor, evaluation of soft tissue masses in the neck prior to intubation, assessment of subglottic diameter for determination of paediatric endotracheal tube size and percutaneous dilatational tracheostomy. With development of better probes, high-resolution imaging, real-time picture and clinical experience, US has become the potential first-line noninvasive airway assessment tool in anaesthesia and intensive care practice.

Detection of subcutaneous and intramuscular air with sonography: a sensitive and specific modality

OBJECTIVES

Soft tissue air may raise suspicion for several life-threatening illnesses. Physical examination has limited sensitivity in detecting air, and computed tomography and magnetic resonance imaging are time-consuming and expensive. Sonography can show soft tissue air, but the sensitivity and specificity in this setting are currently unknown. Therefore, the purpose of this study was to assess the performance characteristics of sonography in depicting the presence, amount, and affected tissue plane in a cadaver model of soft tissue air.

METHODS

We conducted a single-blinded observational cadaver study. Cutaneous sites were selected and marked (≈4 or 5 sites on each of 6 cadavers). An examiner injected air at some sites, recording both the depth (plane) and volume. A second examiner, who was blinded to the injection procedure, examined each site with sonography and recorded the presence or absence of air and the plane (subcutaneous or intramuscular). The results were compared, and statistical analysis was performed.

RESULTS

Twenty-eight sites on 6 cadavers were used. Sites were not used if they were damaged or were within 10 cm of previous dissection. Air was injected in 20 of 28 sites; the remaining 8 were sham injections. Sonography showed air in all of the 20 sites with air injected. No air was detected in 7 of the 8 remaining sham sites, yielding 1 false-positive case. The plane was accurately assessed in all cases. Sensitivity for detection was 100%, and specificity was 87.5%.

CONCLUSIONS

Sonography accurately showed the presence, amount, and anatomic plane of soft tissue air in cadavers with sensitivity of 100%. It warrants investigation as a screening test in patients at high risk for subcutaneous air from conditions such as necrotizing fasciitis and gas gangrene.

Maxillary sinusitis in patients ventilated for a severe head injury and with nostrils free of any foreign body

BACKGROUND

This study aims to determine the frequency of maxillary sinusitis in the patients with traumatic head injury and nostrils free of any foreign body. In addition, the sensitivity and specificity of ultrasonography (US) for the detection of the presence of fluid in maxillary sinuses were evaluated.

PATIENTS AND METHODS

Forty patients with severe traumatic head injury were included in the study. The patients who had displaced maxillary sinus fracture at the medial wall and naso-tracheal and/or naso-gastric tube were excluded. Paranasal computed tomography (CT) was performed along with the routine cranial CT scanning or in case of unknown source of infection and compared with the results of ultrasonographic examination of maxillary sinuses performed by a single radiologist who was unaware of the CT results. In the patients, who had clinical and radiological signs of sinusitis, a trans-nasal puncture was performed using sinoject (SinoJect, ATOS Medical, Sweden), a spring-activated puncture instrument, to take a sample for microbiologic examination and to drain maxillary sinuses.

RESULTS

Eighty-five percent of the patients were tracheotomised on the fifth day (on average) of their intensive care unit (ICU) stay. The frequency of sinusitis in the study group was found to be 32.5% (13 patients). The most frequently isolated species were Pseudomonas spp. (37.5%), Escherichia coli (20.8%) and Peptostreptococcus (16.7%). Five of the aspirates were polymicrobial. The sensitivity, specificity, positive predictive value and negative predictive value of B-mode US, compared with CT for the detection of fluid presence in maxillary sinuses in a 100 maxillary sinus examinations, were 92.2%, 81.6%, 83.9% and 90.9%, respectively.

CONCLUSION

Maxillary sinusitis should be considered as a source of infection or sepsis in patients with traumatic head injury because of its high frequency. US is likely to be used as the first-line diagnostic tool for the determination of fluid in maxillary sinuses, especially in patients who do not require CT or cannot be transported to a radiology unit for CT.

Ventilator-Associated Pneumonia

The area of the alveolar epithelium of the lung is approximately 70 m². This area is constantly in contact with the ambient air and is therefore vulnerable to contamination with airborne microbes and particles of respirable size. Due to the configuration of the respiratory tract, airborne particles having diameters in the range of 0.5-2.0 μ can reach and deposit in the terminal part of the tracheobronchial tree - most bacteria are of this size. In reality, very few bacteria cause infections by spreading via the airborne route (e.g., mycobacteria, viruses, and legionella). Most bacteria cause pneumonia by first colonizing the upper respiratory tract and later descending into the tracheobronchial tree.

A postural change test improves the prediction of a radiological maxillary sinusitis by ultrasonography in mechanically ventilated patients

OBJECTIVE

The aim of this study was to evaluate a postural change test during sinus ultrasound, compared with CT scan, in case of partial sinusogram to differentiate air-fluid level from mucosal thickening.

DESIGN

Prospective clinical investigation.

SETTING

Medical intensive care unit.

PATIENTS

150 intubated patients.

INTERVENTIONS

Patients were examined by sinus ultrasound in half-sitting position. A partial sinusogram was defined as the sole visualization of the hyperechogenic posterior wall of the sinus. In this situation, a postural change was performed and ultrasound was achieved in supine position. If the partial sinusogram disappeared when the patient was placed in a supine position (positive test), the partial sinusogram was an air-fluid level. If the partial sinusogram did not disappear (negative test), we considered it as a mucosal thickening. The CT and ultrasound were performed on the same day. Radiological maxillary sinusitis (RMS) on CT was defined as the presence of an air-fluid level. Absence of RMS on CT was defined as normal sinus or as the presence of mucosal thickening.

MEASUREMENTS AND RESULTS

300 sinuses were examined. A partial sinusogram was found in 90 sinuses and CT scan confirmed the presence of RMS in 55 sinuses (61%). Sensitivity, specificity, positive predictive value, and negative predictive value of postural change test compared with CT were, respectively, 94.6, 85.6, 91.2 and 90.9%. The positive predictive value increased from 61 to 91.2% after the postural change test.

CONCLUSIONS

In case of a partial sinusogram, a postural change increases the accuracy of ultrasound to diagnose RMS.

Point-of-care ultrasound: Infection control in the intensive care unit

Ultrasound provides a diagnostic modality that allows a whole-body approach at the bedside of a critically ill patient in the search for infectious foci. Both common sites of infection, such as the lung and pleura, central veins, and maxillary sinuses, and also less common sites, such as gastrointestinal perforation, sepsis due to mesenteric ischemia, or even meningitis, provide characteristic ultrasound patterns. Optimal use of ultrasound also combines bedside diagnosis with subsequent interventional procedures that can decrease the need for transfer to other imaging and interventional suites. Experience has shown that fevers of unknown origin in the critical care unit often have ultrasound equivalents. Thus, if a comprehensive ultrasound examination is negative, it is now appropriate to speak of fever of unknown sonographic origin.

Role of ultrasound in the airway management of critically ill patients

Ultrasound imaging of the upper airway in critically ill patients offers a number of attractive advantages compared with competitive imaging techniques or endoscopy. It is widely available, portable, repeatable, relatively inexpensive, pain-free, and safe. In this review article, I describe ultrasonographic anatomy of the upper respiratory organs and present the main potential applications of ultrasonography in airway management. The role of ultrasound in endotracheal tube placement, including preintubation assessment, verification of tube position, double-lumen intubation, and extubation outcome, are explained. Also, ultrasound-guided percutaneous tracheostomy, the role of ultrasound in using the laryngeal mask airway, and upper airway anesthesia are described.

Clinical review: Bedside lung ultrasound in critical care practice

Lung ultrasound can be routinely performed at the bedside by intensive care unit physicians and may provide accurate information on lung status with diagnostic and therapeutic relevance. This article reviews the performance of bedside lung ultrasound for diagnosing pleural effusion, pneumothorax, alveolar-interstitial syndrome, lung consolidation, pulmonary abscess and lung recruitment/derecruitment in critically ill patients with acute lung injury.

Transnasal puncture based on echographic sinusitis evidence in mechanically ventilated patients with suspicion of nosocomial maxillary sinusitis

OBJECTIVE

The aim of this prospective study was to evaluate the value of sinus echography results to directly indicate a transnasal puncture in intubated patients with suspicion of nosocomial maxillary sinusitis.

DESIGN

prospective clinical investigation.

SETTING

medical intensive care unit.

PATIENTS

sixty patients undergoing intubation and mechanical ventilation more than 2 days, with a clinical suspicion of maxillary sinusitis with purulent nasal discharge.

INTERVENTIONS

120 sinuses were examined by sinus ultrasound. The image defined as normal was an acoustic shadow arising from the front wall. Two levels of positive echography were described: (1) a partial sinusogram was defined as the visualization of the hyperechogenic posterior wall of the sinus; and (2) a complete sinusogram was defined as the hyperechogenic visualization of posterior wall and the extension by the internal and external walls of the sinus. When sinus ultrasound was positive, a transnasal puncture was performed the same day. The transnasal puncture was positive if a fluid was obtained from sinus aspiration. The transnasal puncture was negative if there was no aspirated material.

MEASUREMENTS AND RESULTS

sinus ultrasound was positive in 84 cases (54 complete sinusograms and 30 partial sinusograms). Seventy-eight of 84 transnasal punctures were positive. Sensitivity of a sinusogram for obtaining positive transnasal puncture was 100%, and specificity was 86% (100% in case of complete sinusogram) in a clinically selected population. The only six negative transnasal punctures were performed in patients with partial sinusogram.

CONCLUSIONS

Ultrasound sinusitis evidence seems to be of value to indicate and perform a transnasal puncture directly, avoiding CT exam.

Hospital-acquired sinusitis is a common cause of fever of unknown origin in orotracheally intubated critically ill patients

Introduction

Sinusitis is a well recognised but insufficiently understood complication of critical illness. It has been linked to nasotracheal intubation, but its occurrence after orotracheal intubation is less clear. We studied the incidence of sinusitis in patients with fever of unknown origin (FUO) in our intensive care unit with the aim of establishing a protocol that would be applicable in everyday clinical practice.

Methods

Sinus X-rays (SXRs) were performed in all patients with fever for which an initial screening (physical examination, microbiological cultures and chest X-ray) revealed no obvious cause. All patients were followed with a predefined protocol, including antral drainage in all patients with abnormal or equivocal results on their SXR.

Results

Initial screening revealed probable causes of fever in 153 of 351 patients (43.6%). SXRs were taken in the other 198 patients (56.4%); 129 had obvious or equivocal abnormalities. Sinus drainage revealed purulent material and positive cultures (predominantly Pseudomonas and Klebsiella species) in 84 patients. Final diagnosis for the cause of fever in all 351 patients based on X-ray results, microbiological cultures, and clinical response to sinus drainage indicated sinusitis as the sole cause of fever in 57 (16.2%) and as contributing factor in 48 (13.8%) patients with FUO. This will underestimate the actual incidence because SXR and drainage were not performed in all patients.

Conclusion

Physicians treating critically ill patients should be aware of the high risk of sinusitis and take appropriate preventive measures, including the removal of nasogastric tubes in patients requiring long-term mechanical ventilation. Routine investigation of FUO should include computed tomography scan, SXR or sinus ultrasonography, and drainage should be performed if any abnormalities are found.

Surgeon-performed ultrasound in the ICU setting

Evaluation of critically ill patients is often challenging due to altered sensorium, underlying disease, and the presence of multiple drains or monitoring devices. In such circumstances, the ability of physicians to perform ultrasound examinations in the intensive care unit provides a useful diagnostic and therapeutic adjunct. In this article,we review the application of surgeon-performed ultrasonography in the evaluation and management of critically ill patients.

Comparison of B-mode ultrasound and computed tomography in the diagnosis of maxillary sinusitis in mechanically ventilated patients

OBJECTIVE

To compare B-mode ultrasound with sinus computed tomograph (CT) scan in the diagnosis of sinusitis in intubated patients undergoing mechanical ventilation.

DESIGN

Prospective, clinical investigation.

SETTING

Medical intensive care unit of a university hospital.

PATIENTS

Fifty patients undergoing intubation and mechanical ventilation more than 2 days, with a clinical suspicion of paranasal sinusitis with purulent nasal discharge.

INTERVENTIONS

One hundred paranasal sinuses were examined. A paranasal CT scan and a B-mode ultrasound were performed the same day. Radiologic maxillary sinusitis (RMS) was defined as complete opacification of the sinus or as the presence of an air-fluid level. Absence of RMS was defined as normal sinus or as the presence of mucosal thickening. Important RMS was defined by total opacity or air-fluid level larger than half of the sinus area. Moderate RMS was defined by air-fluid level inferior than half of the sinus area. For ultrasonographic procedure, the image defined as normal was an acoustic shadow arising from the front wall. Two levels of positive echography were described: 1) a moderate lesion was defined as the visualization only of the hyperechogenic posterior wall of the sinus; 2) an important lesion was defined as the hyperechogenic visualization of posterior wall and the extension by the internal wall of the sinus outlining the hypoechogenic sinus cavity.

MEASUREMENTS AND MAIN RESULTS

Sensibility, specificity, positive predictive value, and negative predictive value of B-mode ultrasound compared with CT were, respectively: 100% (95% confidence intervals [95% CI] = 94.9-100.0), 96.7% (95% CI = 82.8-99.9), 98.6% (95% CI = 92.4-99.9), and 100% (95% CI = 88.1-100). The concordance between a moderate B-mode ultrasound lesion and a moderate RMS on CT, and between an important B-mode ultrasound lesion and an important RMS on CT, assessed using kappa statistics was 93%. The concordance between B-mode ultrasound's results and CT's results assessed using weighted kappa statistics was 97%.

CONCLUSION

B-mode ultrasound may be proposed first-line in a ventilated patient with suspicion of maxillary sinusitis.

Contemporary issues with bacterial infection in the intensive care unit

Nosocomial infection in the critically ill results from defects in the intrinsic barriers to microbial invasion. The diagnosis is complicated by an inability to perform an adequate physical examination in a patient with several compounding findings, usually necessitating sophisticated technologies to aid in the diagnosis. Pneumonia, line sepsis, urosepsis, sinusitis, endocarditis, peritonitis, and acalculous cholecystitis are the more common infections that challenge the care of the critically ill. Antibiotic therapy is adjunctive to efforts to preserve the barrier, but should be started early, should be targeted as specifically as possible to the offending organisms, and should be dosed adequately to ensure an effective concentration in the infected tissue.