Influence of film digitization on radiological interpretation.

Our objective was to evaluate the influence of changing from analogue to digital imaging on interobserver and intraobserver image interpretation. Three radiologists interpreted 96 three image series of occipitomental radiographs of paranasal sinuses from the films and from the corresponding digitized images from the screen. Images were classified according to degree of abnormality as either normal, with mucosal thickening of less than 5 mm, with mucosal thickening of 5 mm or more, total opacity, air-fluid level or polyp or cyst of maxillary sinuses. In the present study we found that there were more differences between two radiologist's interpretations with a single method than in a single radiologist's interpretations between the methods, although radiologists interpreted fewer pathological findings from the digitized images than from the corresponding films. Our data show that the results of image interpretation are preferentially dependent on the reader rather than on the method of reading.

Validity of ultrasonography in diagnosis of acute maxillary sinusitis.

BACKGROUND: Accurate diagnosis of maxillary sinusitis is difficult on the basis of clinical examination only because the signs and symptoms of sinusitis are nonspecific. A simple, rapid, and readily available method for diagnosing maxillary sinusitis in primary care would increase the accuracy of the diagnoses and thus reduce unnecessary antibiotic treatment. OBJECTIVE: To investigate the validity of ultrasonography compared with radiography and magnetic resonance imaging (MRI) in detection of maxillary sinusitis. DESIGN: Ultrasonography and plain-film radiography of the paranasal sinuses were performed on all patients and MRI was performed on 40 randomly selected patients on day 7 of the study. SETTING: Study office at the Department of Pediatrics of Turku University Hospital, Turku, Finland. PATIENTS: One hundred ninety-seven young adults who contacted the study office within 48 hours of the onset of symptoms of the common cold. MAIN OUTCOME MEASURES: Detection rates of maxillary sinusitis by ultrasonography, radiography, and MRI. RESULTS: Acute maxillary sinusitis was diagnosed in 24% of the sinuses by radiography and in 28% by MRI. Compared with MRI findings, the sensitivity of ultrasonography for detection of maxillary sinusitis was 64% (specificity, 95%). Using a 2-step diagnostic approach in which radiological findings were additionally considered in cases of negative ultrasound findings, a sensitivity of 86% (specificity, 95%) was observed. CONCLUSIONS: The high specificity of ultrasonography indicates that a positive ultrasound finding can be regarded as evidence of maxillary sinusitis. The addition of plain-film radiography in cases of negative ultrasound findings increases the diagnostic sensitivity to clinically acceptable levels without loss in specificity. Active use of ultrasonography would substantially decrease the need for radiological imaging of the sinuses and also help reduce unnecessary antibiotic treatment in primary care. Arch Otolaryngol Head Neck Surg. 2000;126:1482-1486

Sinusitis in the common cold.

BACKGROUND: Acute community-acquired sinusitis is considered a bacterial complication of the common cold. Radiologic abnormalities in sinuses occur, however, in most patients with upper respiratory virus infections. OBJECTIVE: Assessment of the occurrence, clinical profile, laboratory findings, and outcome of radiologically confirmed sinusitis was carried out as part of a common cold study in young adults. METHODS: Clinical examinations and radiography of the paranasal sinuses were carried out on days 1, 7, and 21 in 197 patients with the common cold. The symptoms were recorded on diary cards on days 1 to 20. Ten viruses and 5 bacteria were studied as etiologic agents of common cold as reported earlier. Serum C reactive protein concentrations, erythrocyte sedimentation rates, and total white blood cell counts with differentials were determined in 40 randomized subjects on day 7. The effect of 6 days of intranasal fluticasone propionate treatment of the common cold in the prevention of sinusitis was analyzed. RESULTS: On day 7, 39% of patients with the common cold in the placebo group (n = 98) had sinusitis, which we would prefer to call viral sinusitis. The symptoms of patients with sinusitis and those without it were not clinically distinguishable. Viral infection was detected in 81.6% of patients with sinusitis. No significantly increased levels of antibodies to bacteria were detected. Serum C reactive protein concentrations, erythrocyte sedimentation rates, and white blood cell counts were low in patients with sinusitis. All patients made a clinical recovery within 21 days without antibiotic treatment. Fluticasone propionate treatment tended to prevent paranasal sinusitis, especially in rhinovirus-positive subjects. CONCLUSION: Viral sinusitis frequently occurs in the early days of the common cold, but it is a self-limited illness. The sinuses should not be imaged in patients with the common cold if the signs and symptoms of illness gradually become less severe and no specific signs suggestive of bacterial sinusitis occur.

Experiences with a teleradiology system in pulmonary diseases.

Chest radiographs of 43 patients were digitized and sent from Paimio Hospital to Turku University Central Hospital. Fifteen of the patients had a pneumothorax, 12 had interstitial lung disease and 16 were controls. The images were interpreted by 5 radiologists during their duty shift. The first reading session consisted of images with 1,024 x 1,024 pixel resolution and the second of images with 2,048 x 2,048 matrix followed by the original chest radiographs. ROC studies were performed from the answers based on a 5-point confidence scale. In the pneumothorax group the average area under the individual ROC curve was 0.928 with the 1,024 x 1,024 matrix and 0.983 with the 2,048 x 2,048 matrix. In the fibrosis group the average area under the individual ROC curve was 0.877 with the 1,024 x 1,024 matrix and 0.831 with the 2,048 x 2,048 matrix. The results suggest that the 1,024 x 1,024 matrix is adequate in the detection of pneumothoraces and fibrosis.

Changes in muscle structure following tenotomy. A scanning electron microscopical study in the rat.

The alterations caused by Achilles tenotomy in the calf muscles of the rat were studied one, two and three weeks postoperatively by scanning electron microscopy (SEM). One week after tenotomy connective tissue had accumulated in endomyseal and perimyseal structures, which continued to increase even more after two and three weeks. The normal muscle architecture was markedly disturbed and in individual muscle cells hypercontracted segments, longitudinal splitting as well as destruction of myofilaments were found. Apparently due to the loss of muscle tension some muscle cells were reversed on their long axis and fixed with the adjacent collagen fibres. Some muscle cells were spiral in shape or crossing over each other. Formation of myotubes indicated onset of regenerative processes. According to the SEM-analyses tenotomy has many severe deleterious effects on muscle structure. In clinical practice tendon ruptures should therefore be repaired as soon as possible to avoid degenerative--potentially irreversible--changes in the muscular tissue.