HRCT findings in the lungs of primary care patients with lower respiratory tract infection.

PURPOSE: To survey the prevalence and type of lung patterns detectable at high-resolution CT (HRCT) in a primary care population seeking help for cough and fever. MATERIAL AND METHODS: The HRCT patterns of 103 patients obtained at the primary visit to a municipal health centre for cough and fever were evaluated. Forced expiratory examinations were obtained in 93 patients. RESULTS: Lower respiratory tract infection (LRTI)-related findings (present at inclusion, healed at follow-up, not explained by any other factor) were seen in 19 patients (18.7%), of whom 11 also showed opacities, even though of lesser extent, at conventional chest radiography. The following patterns were found: ground-glass opacity (58%), discrete consolidations (52%), confluent consolidations (16%; 1 case with an air bronchogram), air space nodules (10%), peribronchovascular thickening (37%), tree-in-bud pattern (26%), free pleural fluid (5%), and septal thickening (5%). An expiratory mosaic pattern was seen in 19 (20%) out of 93 patients. In addition, lymph node enlargement (>1 cm) was recorded in 7 patients out of 103. CONCLUSION: HRCT is more sensitive than chest radiography in detecting LRTI-related lung lesions in a primary care population. The pattern typically comprises subtle scattered polymorphous opacities with varying attenuation affecting several lung segments. LRTI-related HRCT pattern deserves consideration as a differential diagnostic alternative in patients examined due to any lower respiratory tract symptoms.

CT lung densitometry in assessing intralobular air content. An experimental and clinical study.

PURPOSE: To introduce a parameter called "intralobular air content percentage" to replace the CT number of the lung and to establish a proper protocol for its assessment. MATERIAL AND METHODS: We calibrated the HU (Hounsfield unit) scale for low densities with foam and evaluated the influence of certain acquisition and reconstruction parameters on the accuracy of CT densitometry of the lungs. The reproducibility of the results obtained in human experiments and the intralobular air content percentage of normal and diseased lung tissue were assessed. RESULTS: Air content could be reliably derived from the calibrated CT number of an area within a secondary lobulus. The mean intralobular air content of normal lungs varied from 77.8% to 88.0% in full inspiration. Helical or axial recording with a 10-mm slice thickness, a standard or soft algorithm and high tube currents and voltage settings, was suitable for the measurements. CONCLUSION: Before absolute lung density measurements (as a HU number or an air content percentage), the CT equipment has to be calibrated for low densities. The intralobular air content percentages of cooperative patients were reliably reproducible.

Relationship between calf muscle size and strength after achilles rupture repair.

The object was to study the relationships between calf muscle size and strength in 85 patients an average of 3.1 years after repair of achilles tendon rupture. The isokinetic calf muscle strength results were excellent or good for 73% of the patients, whereas calf muscle size was normal in only 30%. The average plantar flexion peak torque per unit muscle cross-sectional area was higher on the injured side than on the uninjured side. The average calf muscle cross-sectional area deficit was 15+/-9% (p<0.001) of that on the unaffected side, while the average plantar flexion peak torque deficit was speed-dependent, being 9+/-18%, 10+/-18 and 2+/-13% of that on the unaffected side at 30, 90, and 240 degrees/sec (p<0.001). The correlation between cross-sectional area and peak torque varied in the range 0.52-0.61 at 30, 90 and 240 degrees/sec (p<0.001).

Carboxyterminal propeptide of type I procollagen in ELF: elevation in asbestosis, but not in pleural plaque disease.

Markers of collagen metabolism may possibly be used in the assessment of pulmonary involvement in asbestosis-related pulmonary diseases. In this study the levels of the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) were evaluated in bronchoalveolar lavage fluid (BALF), epithelial lining fluid (ELF) and serum from patients with asbestos related pulmonary and pleural involvement. Forty-two consecutive patients with occupational exposure to asbestos fibres, who underwent bronchoscopy and bronchoalveolar lavage (BAL) at the time of the diagnosis were investigated. Five patients were diagnosed as having asbestosis, while 37 showed no parenchymal involvement. Of the latter group, 25 had pleural plaques, while 12 had no detectable changes in chest radiographs. The patients were followed-up for an average of 7 yrs. The PICP in BALF and ELF was detectable in all patients with asbestosis and in 8/37 subjects without parenchymal involvement. The levels of PICP in BALF and ELF were significantly higher in the asbestosis group compared to the patients without asbestosis (9.8+/-1.8 microg x L(-1) versus 0.6+/-1.3 microg x L(-1), p<0.001 and 488.9+/-208.8 microg x L(-1) versus 22.6+/-50.6 microg x L(-1), p<0.001, respectively). Only 1 patient with asbestosis and 3 patients without parenchymal involvement had detectable levels of PIIINP in BALF. The serum levels of PICP and PIIINP did not differ between the patients with asbestosis and those with exposure to asbestos fibres without asbestosis and were within the normal range. None of the 37 patients exposed to asbestos fibres without parenchymal involvement at the baseline developed asbestosis during the follow-up period of 7 yrs. In conclusion, the data show that the carboxyterminal propeptide of procollagen type I, but not the aminoterminal propeptide of type III procollagen is highly elevated in bronchoalveolar lavage fluid and epithelial lining fluid in patients with asbestosis, but not in those without parenchymal involvement. This suggests that the determination of carboxyterminal propeptide of procollagen type I in bronchoalveolar lavage fluid could be used as a marker of parenchymal involvement in patients exposed to asbestos fibres.

Role of metaphyseal cancellous bone defect size in secondary displacement in Colles' fracture.

The purpose of this study was to evaluate the role of the metaphyseal cancellous bone defect size in secondary dislocation of Colles' fracture. Thirty-five patients with a dislocated Colles' fracture were examined by computed tomography (CT) for metaphyseal bone defects. The size of the defect was assessed and related to the surface area of the cross-section of the distal radius at the site of the defect. The relative size of the defect correlated with the severity of dorsal angulation of the fracture but not with the shortening of the radius seen after cast immobilization. We concluded that secondary displacement of the distal radius is partly mediated through the metaphyseal cancellous bone defect, and to prevent malunion in dorsal angulation, operative treatment or possibly filling of the defect should be considered even as early as during primary reduction if a large defect is suspected.

An allele of COL9A2 associated with intervertebral disc disease.

Intervertebral disc disease is one of the most common musculoskeletal disorders. A number of environmental and anthropometric risk factors may contribute to it, and recent reports have suggested the importance of genetic factors as well. The COL9A2 gene, which codes for one of the polypeptide chains of collagen IX that is expressed in the intervertebral disc, was screened for sequence variations in individuals with intervertebral disc disease. The analysis identified a putative disease-causing sequence variation that converted a codon for glutamine to one for tryptophan in six out of the 157 individuals but in none of 174 controls. The tryptophan allele cosegregated with the disease phenotype in the four families studied, giving a lod score (logarithm of odds ratio) for linkage of 4.5, and subsequent linkage disequilibrium analysis conditional on linkage gave an additional lod score of 7.1.

Type III and type I procollagen markers in fibrosing alveolitis.

Deposition of types I and III collagen is a typical feature in the development of pulmonary fibrosis. We assessed the propeptides of these procollagens as prognostic markers in 18 patients with fibrosing alveolitis. We analyzed the amino-terminal propeptide of type III procollagen (PIIINP) and the carboxy-terminal propeptide of type I procollagen (PICP) from samples of bronchoalveolar lavage fluid (BALF) and serum, and also estimated their concentrations in epithelial lining fluid (ELF) by the urea method. The level of PIIINP in serum (p < 0.05), BALF (p < 0.05), and ELF (p < 0.05), and the levels of PICP in BALF (p < 0.001) and ELF (p < 0.001) but not in serum, were significantly increased in the patients with fibrosing alveolitis as compared with 17 controls who had been investigated for minor respiratory symptoms. In the BALF and ELF of patients with fibrosing alveolitis, PICP but not PIIINP had significant negative correlations with the specific diffusion coefficient for carbon monoxide (DLCO/ VA). The amino-terminal propeptide of type III procollagen and the carboxy-terminal propeptide of type I procollagen in BALF correlated significantly with one another. During the follow-up period of 6 yr, seven of the 18 patients with fibrosing alveolitis died of the disease, 3 others died of malignancy, and one patient died from an unknown cause. DLCO (p < 0.05) differed significantly between the surviving patients and those who died of fibrosing alveolitis, and detectable PIIINP in BALF predicted death from fibrosing alveolitis (p = 0.05). In conclusion, these results show that PIIINP in BALF, ELF, and serum, and PICP in BALF and ELF, are increased in patients with fibrosing alveolitis. A high level of PICP in BALF, and especially in ELF, suggests a chronic process and increased synthesis of type I collagen in the lungs, whereas PIIINP in BALF and ELF suggests active disease and a poor prognosis.

Evaluation of humeral head erosions in rheumatoid arthritis: a comparison of ultrasonography, magnetic resonance imaging, computed tomography and plain radiography.

The value of ultrasonography (US), magnetic resonance imaging (MRI), computed tomography (CT) and plain radiography (PR) in detecting bone erosions on the humeral head was evaluated in a study of 26 in-patients (26 shoulders) with rheumatoid arthritis (RA). MRI depicted humeral erosions in 25 (96%), US in 24 (92%), CT in 20 (77%) and PR in 19 (73%) of the 26 shoulders. MRI and US were superior to CT in detecting small erosions. US was the most sensitive method to show surface erosions on the greater tuberosity. US, CT and MRI detected large erosions quite similarly. PR frequently missed small erosions. In the evaluation of early erosions in the rheumatoid shoulder, US and MRI are more sensitive methods than the traditionally used PR. US and MRI are suitable for the evaluation of soft-tissue involvement in the rheumatoid shoulder, but also for the detection of bone erosions of the humeral head.

Computed tomographic evaluation of retrosternal adhesions after pericardial substitution.

BACKGROUND: Reoperative median sternotomy can result in cardiac injury and serious bleeding, with the rate ranging from 2% to 6%. Closure of the native pericardium can maintain a preventing plane of cleavage. In patients in whom primary pericardial closure is not possible, several substitutes have been tried with variable results. We conducted a prospective study to evaluate the clinical feasibility of polytetrafluoroethylene and polyglycolic acid patches as pericardial substitutes, using computed tomography for imaging the postoperative state of the retrosternal space. METHODS: The basic population comprised 540 patients who were scheduled for coronary artery bypass grafting, and 52 of them who met the research criteria were chosen for computed tomographic evaluation after 5 years after the primary operation. RESULTS: As a substitute, polytetrafluoroethylene seemed to be less adhesive to the posterior surface of the sternum. Total adhesion scores were also statistically significant (p < 0.001) to the advantage of polytetrafluoroethylene over polyglycolic acid as a pericardial substitute. CONCLUSIONS: Polytetrafluoroethylene membrane seems to be capable of minimizing retrosternal adhesion formation and thus it may protect the heart during subsequent reoperative sternotomy.

High-resolution computed tomography for the diagnosis of community-acquired pneumonia.

We compared high-resolution computed tomography (HRCT) with chest radiography (CR) to determine if there is any advantage to using HRCT in the diagnosis of community-acquired pneumonia (CAP). Simultaneously obtained chest radiographs were compared with HRCT scans for 47 patients with clinical symptoms and signs suspicious for CAP, HRCT identified all 18 CAP cases (38.3%) apparent on radiographs as well as eight additional cases (i.e., 55.3%); P = .004. The corresponding figures for bilateral involvement were six by CR (33.3%) and 16 by HRCT (61.5%), P = .001. CR did not show changes particularly affecting the upper and lower lung lobes and the lingula. Bronchopneumonia was visualized by CR in 11 cases (61.1%) and by HRCT in 22 cases (84.6%). The corresponding figures for airspace pneumonia were four (22.2%) and one (3.8%), respectively. The use of HRCT seems to increase the number of CAP cases confirmed by imaging and to improve the accuracy of diagnosing and typing of CAP.

Multiplanar and 3D CT of acetabular fractures.

PURPOSE: To establish a standard protocol for the multiplanar (MPR) and 3D shaded surface display (SSD) reconstruction of CT data on acetabular fractures, and to assess the usefulness of these reformats. MATERIAL AND METHODS: Acetabular fractures in 15 patients were imaged by means of plain radiographs, transaxial CT, MPR reformats, and SSD reformats. RESULTS: The classification of the acetabular fracture was revised in 7/15 cases when the transaxial CT images were read after the plain radiographs. Although the MPR and SSD reformats did not alter the classification, they did add to the degree of confidence in the diagnosis in 9/15 cases. In 2 patients, the MPR and SSD reformats indicated operative instead of conservative treatment. In the MPR reformats, the following views were considered essential in all cases: (a) along the anterior column; (b) along the posterior column; and (c) along both columns and the inferior ramus. In the SSD reformats, the following views were considered essential in all cases: (d) the latero-caudal en face view into the acetabulum; and 180 degrees opposite to this, (e) the medio-cranial view (facing the quadrilateral plate). In 10/15 cases, these views were all that was needed for classification. It was, however, essential to remove the femur from the images before reconstructing the SSD views. CONCLUSION: Complex acetabular fractures with displacement should be evaluated by means of transaxial CT and additional MPR and SSD reformats. The use of appropriate standard MPR and SSD views shortens the time required to produce the reformats and thereby maximizes the benefit gained.

A simple device for the stereoscopic display of 3D CT images.

We describe a simple device for creating true 3D views of image pairs obtained at 3D CT reconstruction. The device presents the images in a slightly different angle of view for the left and the right eyes. This true 3D viewing technique was applied experimentally in the evaluation of complex acetabular fractures. Experiments were also made to determine the optimal angle between the images for each eye. The angle varied between 1 degree and 7 degrees for different observers and also depended on the display field of view used.

Ultrasound evaluation of the acromioclavicular joint.

OBJECTIVE: To evaluate the value of ultrasonography in assessing arthritic acromioclavicular (AC) joints. METHODS: One hundred twenty-six AC joints of 63 healthy subjects (2 groups) were prospectively examined by ultrasound to determine the-normal limits of capsular distention and the width of the joint space. Thirty-three AC joints of 32 patients with chronic arthritis were evaluated by ultrasound and, for comparison, by radiography, computed tomography (CT), and magnetic resonance imaging (MRI). RESULTS: The mean ultrasonographic distance of the joint capsule from the bone rim was 2.2 mm +/- standard deviation (SD) 0.5 mm in 21-32-year-old control subjects and 2.9 +/- 0.7 mm in 37-81-year-old control subjects. The mean width of the joint space was 4.1 +/- 0.9 mm and 3.5 +/- 0.9 mm in the same control groups, respectively. In detecting soft tissue changes in arthritic AC joints MRI was better than ultrasound. In revealing bony surface changes, CT was the best method and radiography was least sensitive but quite specific. Our most prominent finding was that ultrasound is able to exclude joint inflammation; when the ultrasonographic distance of the joint capsule from the bone rim was < 3 mm, there was no synovial hypertrophy or effusion on MRI scans. CONCLUSION: Ultrasound can detect AC joint changes reliably. It is able to exclude joint inflammation. Effusion in the AC joint may reflect inflammation, but may also be a sign of degeneration.

Hepatobiliary and coexisting pancreatic duct abnormalities in patients with inflammatory bowel disease.

BACKGROUND: We performed a cross-sectional study to evaluate the prevalence of hepatobiliary disease in unselected patients with inflammatory bowel disease (IBD), to estimate the frequency of coexisting cholangiographic and pancreatographic duct abnormalities, and to correlate the findings with clinical, endoscopic, and histologic variables. METHODS: We screened 237 IBD patients for increased liver function values. Further, hepatobiliary evaluation consisted of transabdominal ultrasonography, endoscopic retrograde cholangiopancreatography (ERCP), and a liver biopsy. In addition, we evaluated the ERCP findings of patients with abnormal pancreatic screening tests (pancreatic enzymes or para-aminobenzoic acid excretion). RESULTS: Laboratory signs of hepatobiliary disease were found in 37 (16%) of our IBD patients. Abnormal liver test results were commoner in patients with Crohn's disease (CD) than in patients with ulcerative colitis (UC) (30.4% versus 11.2%, P < 0.05), and a similar trend was observed in the frequency of primary sclerosing cholangitis (PSC) in the respective groups of IBD patients. When the ERCP findings were combined with liver histology, 26 (11% of the whole study group) patients with PSC were found, with small-duct disease included. In 23 (10% of the whole study group) patients, definite cholangiographic changes consistent with PSC were found. Eleven (48%) of these showed coexisting pancreatic duct abnormalities. The prevalence of coexisting cholangiographic and pancreatographic duct changes in the whole study group was 4.6%. CONCLUSION: Hepatobiliary disease is at least equally common in patients with UC and CD. Coexisting cholangiographic and pancreatographic duct abnormalities in patients with IBD are relatively frequent and are considered extraintestinal manifestations of IBD.

Helical CT in evaluation of the bronchial tree.

PURPOSE: To establish a protocol for and to assess the value of helical CT in the imaging of the bronchial tree. MATERIAL AND METHODS: Noncontrast helical CT was performed in 30 patients undergoing fiberoptic bronchoscopy for different reasons. Different protocols were compared; they included overlapping 10 mm, 5 mm, or 3 mm slices and non-tilted, cephalad or caudad tilted images. Ordinary cross-sectional and multiplanar 2D reformats were applied for visualization of the bronchial branches. The effect of increasing the helical pitch was tested in one patient. RESULTS: A total of 92.1-100% of the segmental bronchi present in the helical acquisitions were identified by the different protocols. The collimation had no significant impact on the identification of the bronchial branches, but utilization of 3-mm overlapping slices made it easier to distinguish the nearby branches and provided better longitudinal visualization of the bronchi in 2D reformats. The tilted scans illustrated the disadvantage of not covering all segmental bronchi in one breath-hold. An increase of the pitch from 1 to 1.5 did not cause noticeable blurring of the images. CT and bronchoscopic findings correlated well in the area accessible to bronchoscopy, but CT detected 5 additional pathological lesions (including 2 cancers) in the peripheral lung. CONCLUSION: Helical CT supplemented with bronchography-like 2D reformats provides an effective method complementary to bronchoscopy in the examination of the bronchial tree.