Search PubMed⌕ Search

Biomedical subjects

P Grenier

Publications and source records attributed to P Grenier.

At least 37 records · Page 2Linked to original sources
PubMed1999

Contrast-enhanced helical CT for pulmonary embolism detection: inter- and intraobserver agreement among radiologists with variable experience.

OBJECTIVE: The objective of this study was to evaluate inter- and intraobserver agreement in the diagnosis of central pulmonary embolism using contrast-enhanced helical CT among observers with variable experience in the interpretation of pulmonary CT angiograms. MATERIALS AND METHODS: Helical CT angiograms of 60 patients clinically suspected of having pulmonary embolism were analyzed retrospectively and independently by two chest radiologists, one cardiovascular radiologist, and three general radiologists. The films were rated a second time by the chest radiologists to assess intraobserver variability. Findings for pulmonary embolism were categorized as positive, negative, or indeterminate at the main, lobar, and segmental pulmonary artery levels. RESULTS: The observers interpreted 19-21 CT angiograms as positive for pulmonary embolism (mean, 19.7) and one to six as indeterminate (mean, 3.2). Agreement occurred among all observers in 50 patients (83.3%), among five observers in six patients (10.0%), among four observers in three patients (5.0%), and among three observers in one patient (1.7%). Interobserver agreement was very good (kappa, .85) for the diagnosis of pulmonary embolism on a per-patient basis. Agreement on a per-artery basis for all arteries was moderate (66%; kappa, .56); for lobar arteries was good (83%; kappa, .75); and for segmental arteries was moderate (57%; kappa, .47). Mean intraobserver agreement on a per-patient basis was very good (93%; kappa, .87). CONCLUSION: Inter- and intraobserver agreement in the diagnosis of pulmonary embolism with helical CT is very good despite a wide variety of experience among radiologists.

Adult↗
PubMed1999

[Bronchiolitis: computed tomographic findings].

Bronchiolitis includes a broad range of conditions with variable clinical, functional and morphological expression. Bronchiolar disease may be a primary or a secondary condition. Non-specific inflammatory changes are observed at the histology examination, involving respiratory and membranous bronchioles with or without extension to the alveoli. CT findings vary from subtle to quite marked abnormalities related to alveolar involvement, including small centrilobular lesions (nodular and branching linear opacities), ground-glass attenuation, and airspace consolidation. All are potentially reversible and treatable. Cicatrization processes may lead to constrictive bronchiolitis, an irreversible condition characterized by circumferential submucosal or periadventitial fibrosis causing an obstruction of the bronchiolar lumen. CT findings include decreased lung attenuation and expiratory air trapping within the areas of bronchiolar obstruction. The contrast with normally ventilated and perfused areas creates a mosaic perfusion pattern.

Airway Obstruction↗
PubMed1999

Computed tomography in the assessment of diffuse lung disease.

Computed tomography (CT) has a significant impact on the evaluation of patients suspected of having diffuse lung disease. The technique is based on thin-section scans and high-resolution reconstruction. CT interpretation is based on a recognition of the main pattern, associated findings, and distribution of the lesions assessed at the regional level as well as the level of the secondary pulmonary lobule. CT may demonstrate clinically suspected abnormalities undetected on the radiographs. It may have characteristic pictures in patients with non specific findings on the radiograph. It can be used to limit the differential diagnosis to a few possibilities. In selected cases, in the presence of the appropriate clinical setting, CT appearances can be diagnostic or so strongly suggestive that lung biopsy can be avoided. When a lung biopsy is indicated, CT has a considerable value in determining the most appropriate site for the biopsy. To a certain extent, CT may also provide information on disease activity and prognosis, particularly in the differentiation between inflammatory changes, potentially treatable or reversible, and irreversible lung fibrosis.

Biopsy↗
PubMed1999

[CT angiography of the pulmonary arteries].

CT angiography of the pulmonary arteries recently appeared as an alternative method potentially useful in the diagnosis of pulmonary embolism. Technical aspects, normal aspects and variants, diagnostic criteria of pulmonary embolism as well as potential pitfalls are successively described. The accuracy of CT angiography compared with pulmonary angiography and V-Q scintigraphy has been evaluated in several studies. The method appears accurate for the diagnosis of pulmonary embolism at the level of segmental arteries. The signification of more distal embolism remains however controversed. CT angiography seems to play a major role in the diagnosis of pulmonary embolism, as well as echo-doppler of the legs.

Angiography↗
PubMed1999

[Colonic tubular adenoma following ureterosigmoidostomy: CT features].

We report a case of benign colonic tubular adenoma arising in a 36-year-old female at the site of ureterosigmoidostomy performed 25 years before. The tumor was revealed by recurrent episodes of pyelonephritis; hydronephrosis was present. On colonic enema, the tumor appeared lobulated, 4 cm in diameter. CT scan showed a multiloculated mass, which enhanced after injection. Pathology revealed a tubular adenoma of the colon with cystic dilatation of glandular structures. The role of imaging studies in the follow-up of patients after ureterosigmoidostomy is discussed.

Adenoma↗
PubMed1998

Perirenal textiloma: MR and serial CT appearance.

We describe changes in imaging features of a textiloma (retained surgical sponge or retained foreign body) left in the renal fossa after exploratory renal surgery. One year after the initial surgery, the MR aspect of the textiloma was not specific, with a homogeneous low signal intensity on T1-weighted images. Serial CT examinations over 4 years demonstrated progressive growth and calcification of the mass which appeared pseudocystic with a peripheral inflammatory wall. Granulomas caused by a retained surgical sponge should be considered as a cause of retroperitoneal mass in patients with a history of prior surgery.

Adult↗
PubMed1998

Congenital anomalies of tracheobronchial branching patterns: spiral CT aspects in adults.

Congenital abnormalities of the bronchi have been classically described with chest X-rays, conventional tomography, bronchography, CT and MR imaging. Recently, the capacity of spiral CT to explore a complete volume with no gap and excellent multiplanar reformations has been emphasized. The contribution of this technique to the analysis of congenital anomalies of tracheobronchial branching patterns encountered in adult patients is illustrated. Agenesis, aplasia, and hypoplasia are discussed, followed by bronchial atresia and abnormalities of bronchial divisions. In most cases spiral CT permits a full and correct evaluation of the malformation as well as its associated anomalies. It appears therefore to be the preferable technique for studying such anomalies of the tracheobronchial tree. Moreover, knowledge of CT aspects of the main congenital bronchial abnormalities along with complete visualization of the tracheobronchial tree will probably lead to detection of more incidental anomalies.

Adult↗
PubMed1998

Respiratory bronchiolitis: radiographic and CT findings in a pathologically proven case.

A small number of cases of cigarette-smoking-associated respiratory bronchiolitis (RB) with positive findings on the chest radiograph have been reported in the literature. High-resolution computed tomography (HRCT) findings are available in even fewer cases. We describe the case of an asymptomatic female smoker presenting with a reticulomicronodular infiltrate on a routine chest radiograph. High-resolution CT was characterized by ground-glass opacities and centrilobular micronodules with an upper lobe predominance. Surgical biopsy revealed peribronchiolar lesions, with accumulation of brown pigmented macrophages in the lumen of alveolar and bronchiolar lumen, consistent with the pathologic diagnosis of RB.

Aged↗
PubMed1998

Expiratory CT scans for chronic airway disease: correlation with pulmonary function test results.

OBJECTIVE: The purpose of our study was to correlate findings on expiratory CT scans with results of pulmonary function tests (PFTs) and to determine whether these techniques may be complementary in assessing airway obstruction. MATERIALS AND METHODS: Seventy-four patients with suspected chronic airway disease and 10 healthy nonsmokers underwent inspiratory and expiratory CT scans and PFTs. An air trapping score, corresponding to the ratio of the cross-sectional air trapping area versus the total cross-sectional lung area on expiratory CT, and a reduction score, representing the change in cross-sectional lung area at inspiration and expiration, were calculated using a quantitative grid. The two scores were then correlated with the results of the PFTs. RESULTS: Expiratory air trapping was seen in 18 (51%) of 35 patients with severe airway obstruction (forced expiratory volume in 1 sec [FEV1]:vital capacity < 80%) (group A), in 21 (72%) of 29 patients with predominantly small airways obstruction (abnormal flow-volume curve and FEV1:vital capacity > or = 80%) (group B1), and in four (40%) of 10 patients with normal PFT results (group B2). Expiratory air trapping was never seen in the 10 healthy subjects. Air trapping scores were 27%, 12%, and 8% for groups A, B1, and B2, respectively, with significant negative correlations with FEV1 (r = -.45), FEV1:vital capacity (r = -.31), and forced expiratory flow at 25% of vital capacity (r = -.57). Reduction scores were 18%, 30%, 35%, and 43%, for the groups A, B1, B2, and the healthy group, respectively, with significant correlations with all the PFT indexes (r = .35 to .66) except total lung capacity. CONCLUSION: Air trapping may permit detection of airway obstruction in patients with clinically suspected chronic airway disease even when PFTs are normal. Furthermore, expiratory CT allows one to calculate a reduction score for a cross-sectional lung area that appears to be better correlated with the degree of airway obstruction measured on PFTs.

Adult↗
PubMed1998

Association of small cell lung cancer and the anti-Hu paraneoplastic syndrome: radiographic and CT findings.

OBJECTIVE: The anti-Hu syndrome (bearing the name of the patient in whom the antibody was first discovered) is characterized by a paraneoplastic encephalomyelitis or sensory neuronopathy and the presence of a specific antibody in the serum or CSF and is associated with lung cancer in most patients who have the syndrome. The objective of this study was to determine the relative merits of chest radiography and CT in the imaging of patients with the anti-Hu syndrome. MATERIALS AND METHODS: Chest radiographic and CT findings of 11 patients with anti-Hu syndrome were reviewed and correlated with results of bronchoscopy, surgery, or autopsy. RESULTS: Ten of the 11 patients had small cell lung cancer; in the remaining patient, no cancer was found. Small cell lung cancer was first revealed on radiographs in one patient and solely on CT in the remaining nine patients with small cell lung cancer. In six of these nine patients, the initial CT findings were positive for lung cancer. Tumor was found on follow-up CT in 4-8 months when initial CT findings were negative. Mediastinal adenopathy was present in all 10 cancer patients. Hilar adenopathy was present in four. Parenchymal involvement was seen in three of the 10 patients with cancer. In two patients, the only CT finding of small cell lung cancer was one mediastinal lymph node of 10 mm in each patient. CONCLUSION: Chest CT should be recommended for patients with anti-Hu syndrome, even when chest radiographic findings are interpreted as normal.

Aged↗
PubMed1998

[The contribution x-ray computed tomography in chronic diffuse infiltrative lung disease].

Computed tomography (CT) may be useful at all stages of management of chronic infiltrative lung disease. It contributes to diagnosis and evaluation of inflammation and fibrosis, helping the therapeutic decision and appreciating the response to treatment. It contributes to follow-up in the course of the disease. Some further works are necessary to know the indications of CT and the frequency of examinations.

Bronchography↗
PubMed1998

[Subacute intestinal obstruction due to bladder distension].

We report a case of subacute bowel obstruction due to a compression of the rectosigmoid junction by a chronically distended bladder, occurring in a 91-year-old male suffering from a long-standing diabetes mellitus and a prostatic adenoma. Radiographic, water-soluble contrast enema and pelvic CT features are reported.

Aged↗
PubMed1998

[Cystic pulmonary metastasis simulating a diagnosis of histiocytosis X].

A case of cystic pulmonary metastases from a renal origin simulating lung histiocytosis on high-resolution CT is presented. This diagnosis was suggested because of the presence of cystic lung lesions, micronodules and recurrent pneumothoraces in a male smoker. The diagnosis was reviewed after lung biopsy and demonstration of a renal mass.

Aged↗
PubMed1997

MRI of plantar fasciitis.

At present, MRI is the only imaging method that can precisely visualize lesions of the superficial plantar aponeurosis, whether they be musculoaponeurositides, enthesopathies or tears, and whether they be acute or chronic, with or without complications. By its direct visualization of the lesion, MRI enables an accurate assessment of the injury to be made and thereby better orients the therapeutic strategy.

Fascia↗
PubMed1997

Pulmonary Langerhans cell histiocytosis: evolution of lesions on CT scans.

PURPOSE: To document the evolution of pulmonary lesions of Langerhans cell histiocytosis (LCH) with sequential computed tomography (CT). MATERIALS AND METHODS: Initial and final CT scans of 21 patients with LCH and CT evidence of pulmonary disease were compared retrospectively. Histologic confirmation of pulmonary involvement was available in 11 patients. RESULTS: On initial CT images, a nodular pattern (n = 14) was seen more frequently than a cystic pattern (n = 7). On final CT images, a cystic pattern (n = 14) was seen more often than a nodular one (n = 6). There was complete resolution of parenchymal abnormality in one case. Nodular opacities, thick-walled cysts, and ground-glass opacities underwent regression. Thin-walled cysts, linear opacities, and emphysematous lesions remained unchanged or progressed. CONCLUSION: Pulmonary CT allows good assessment of the evolution of LCH lesions. Nodular lesions probably represent active disease and often undergo regression or transform into cysts.

Adult↗