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Resume L’angioscanographie double energie a la recherche d’une embolie pulmonaire aigue (EPA) est un examen simple a l’acquisition, mais egalement a la reconstruction. Il repose sur l’interpretation d’une imagerie standard toujours optimisee et d’une imagerie complementaire de 2 types : imagerie morphologique monoenergetique et/ou imagerie de perfusion pulmonaire.

Resume La reussite d’une angioscanographie simple energie pour recherche d’EPA utilise un tres grand nombre de parametres, tous d’egale importance. Depuis l’introduction du mode d’acquisition spiralee (helicoidale), ils se sont perfectionnes au point d’en faire maintenant un examen fiable, aux echecs peu frequents a la condition d’une technique rigoureuse.

Objectives This study evaluated a new strategy to assess technical success after standard and complex endovascular aortic repair (EVAR), combining completion contrast enhanced cone beam computed tomography (ceCBCT) and post-operative contrast enhanced ultrasound (CEUS). Methods Patients treated with bifurcated or fenestrated and branched endografts in the hybrid room during the study period were included. From December 2012 to July 2013, a completion angiogram (CA) was performed at the end of the procedure, and computed tomography angiography (CTA) before discharge (group 1). From October 2013 to April 2014, a completion ceCBCT was performed, followed by CEUS during the 30 day post-operative period (group 2). The rate of peri-operative events (type I or III endoleaks, kinks, occlusion of target vessels), need for additional procedures or early secondary procedures, total radiation exposure (mSv), and total volume of contrast medium injected were compared. Results Seventy-nine patients were included in group 1 and 54 in group 2. Peri-operative event rates were respectively 8.9% ( n = 7) and 33.3% ( n = 18) ( p = .001). Additional procedures were performed in seven patients (8.9%) in group 1 versus 17 (31.5%) in group 2 ( p = .001). Two early secondary procedures were performed in group 2 (3.7%), and three (3.8%) in group 1 ( p = .978). Median radiation exposure due to CBCT was 7 Gy cm 2 (5.25–8) (36%, 27%, and 9% of the total procedure exposure, respectively for bifurcated, fenestrated, and branched endografts). CEUS did not diagnose endoleaks or any adverse events not diagnosed by ceCBCT. Overall radiation and volume of contrast injected during the patient hospital stay in groups 1 and 2 were 34 (25.8–47.3) and 11 (5–20.5) mSv, and 184 (150–240) and 91 (70–132.8) mL respectively (reduction of 68% and 50%, p Conclusions Completion ceCBCT is achievable in routine practice to assess technical success after EVAR. Strategies to evaluate technical success combining ceCBCT and CEUS can reduce total in hospital radiation exposure and contrast medium volume injection.

Resume Le radiologue occupe une place primordiale dans l’approche multidisciplinaire permettant le diagnostic des pneumopathies infiltrantes diffuses, avec comme outil le scanner thoracique haute resolution (TDM HR). Son role est d’identifier l’atteinte des differents compartiments pulmonaires touches (alveolaire, bronchiolaire et interstitiel) sur la base des lesions elementaires permettant ainsi d’etablir des correlations avec les lesions anatomopathologiques. L’integration des donnees cliniques permet ensuite d’approcher un diagnostic etiologique. Cette approche par analyse des differents compartiments pulmonaires semble la plus efficace bien qu’il reste certaines zones d’ombre a preciser.

To assess the accuracy and torerability of gadolinium-enhanced thoracic CTA using a 64 MDCT compared to a 16 MDCT. Because this study was started prior to the description of NSF, particular attention was paid to long-term follow-up of the patient population.The study protocol was approved by the ethics committee of our institution and informed consent was obtained from all patients. Fourteen patients (Group 1) (9 males and 5 females; mean age: 64.3 years) with contraindication to the administration of iodinated contrast material underwent thoracic CTA (collimation: 32 x 2 x 0.6 mm; pitch: 1.2) with gadolinium administration (0.5 mml/ml) at 0.4 mmol/kg injected at 6 ml/sec with evaluation of clinical and biological tolerability of the gadolinium based contrast agent. Results from this patient population were compared to results from a population of 31 patients (21 males; 10 females; mean age: 63.2 years) (Group 2) imaged on a 16 MDCT. All patients were folloowed-up for a mean time of 22.6 months.Using a mean contrast volume (standard deviation) that was not significantly different (Group 1: 54.8+/-11 ml; Group 2: 53.4+/-6.9 ml) (p=0.94), patients in Group 1 underwent complete thoracic CTA whereas patients in Group 2 underwent CTA of only the middle third of the thoracic region. All CTA examinations were diagnostic for Group 1 and Group 2 patients; however, evaluation of subsegmental vessels was possible in a significantly larger proportion of patients in Group 1 (10/14; 72%) compared to Group 2 (6/31; 19%) (p=0.003). Mean attenuation values within pulmonary arterial branches were similar for Groups 1 and 2 (central arteries: 194.5+/-51.3 HU vs 180.6+/-53.8 HU; p=0.38) (lobar arteries: 208.5+/-52.5 HU vs 189.9+/-60.1 HU; p=0.33) (segmental arteries: 220.4+/-50.4 HU vs 201.5+/-54.7 HU; p=0.42). Transient alteration of renal function was recorded in one patient from Group 1 with severe pre-existing chronic renal failure. No change in renal function was observed for Group 2 patients. No case of NSF was reported in patients with pre-existing renal failure at the time of enrollment.The use of gadolinium-based contrast agent for thoracic CTA using a 64 MDCT provides diagnostic quality examinations in all patients with improved image quality compared to a 16 MDCT. No complication other than transient alteration of renal function was observed. Because the likelihood of developing NSF may vary with the type of gadolinium-based contrast agent used, the least toxic agent should be used.

The authors report two cases of portopulmonary anastomosis to show the value of multidetector CT with MPR MIP reformations in the diagnosis of portopulmonary venous anastomosis. This diagnosis has consequences in the treatement of hypoxemia in patients with chronic liver disease and embolization of bleeding esophageal varices in these patients.

This review consists in three main topics. At this time, technology does not allow for optimal functional and morphological evaluation of the cardiac chambers. However, a precise pretherapeutic map of the systemic supply of the lung can be non invasively obtained.

Interstitial lung disease is one of the most common respiratory manifestations in polymyositis and dermatomyositis. It still remains a severe complication of the disease, leading to death related to ventilatory insufficiency in 30-66% of patients.Time onset of interstitial lung disease is variable, although interstitial lung disease onset precedes initial manifestations of polymyositis/dermatomyositis in roughly half of the patients. Moreover, clinical presentation of interstitial lung disease can be dichotomized, according to patients' pulmonary manifestations, into: 1) both acute and aggressive lung disease similar to Hamman-Rich syndrome; 2) slowly progressive lung disease; and 3) an asymptomatic pattern. The methods of choice adopted for early diagnosis of interstitial lung disease are high-resolution computed tomography scan and pulmonary function tests, which should be performed during both initial evaluation of polymyositis/dermatomyositis and follow-up. Because anti-JO1 antibody is considered to be a marker of interstitial lung disease in polymyositis/dermatomyositis, close pulmonary follow-up of anti-JO1-positive patients with polymyositis is therefore required for early detection of subclinical impairment. Furthermore, histological lung findings provide prognostic data; patients with bronchiolitis obliterans organizing pneumonia (BOOP) indeed appear to have a more favorable outcome than those with usual interstitial pneumonia or diffuse alveolar damage. Finally, as a guide to both the severity and progress of interstitial lung disease, the significance of other investigations, notably bronchoalveolar lavage, remains controversial.Specific therapy of interstitial lung disease has not yet been clearly established in polymyositis/dermatomyositis patients. Corticosteroid therapy is considered the first line of therapy for polymyositis/dermatomyositis patients with interstitial lung disease. The association of cyclophosphamide and corticosteroids may be the most effective in patients with steroid-resistant interstitial lung disease. Early diagnosis and management of this disease is therefore of the utmost importance.

To our knowledge, conventional chest radiography is not likely to become obsolete or disappear from the daily practice of medical imaging. As such, it is important to insure that chest radiographs are acquired using optimal technique. Evaluation of chest radiograph findings must be comprehensive and the art of reading chest radiographs must be well thought to physicians in training. Chest radiography is characterized by the projection of tridimensional anatomical structures and disease processes onto a two-plane radiographic film. Correlation with cross-sectional data obtained from CT may greatly enhance the understanding and interpretation of conventional chest radiographs. Indeed, review of CT images facilitates anatomical understanding of the segmental and subsegmental anatomy, of the superior segments of the lower lobes and of the three dimensional orientation of the fissures. CT also has improved the understanding of some chest radiography findings. Careful review of findings at chest radiography is helpful to optimize CT acquisition protocols in order to reduce some of the pitfalls of CT and improve detection of specific processes that could otherwise be poorly demonstrated or overlooked. Chest radiographs can sometimes detect diseases or abnormalities that are difficult to demonstrate at CT.

Pulmonary hypertension is a severe complication of systemic sclerosis and has emerged as a major cause of morbidity and mortality in this condition. Treatment is all the more efficient as pulmonary hypertension is early diagnosed. A good knowledge of the clinical, biological and functional features of pulmonary hypertension in systemic sclerosis is therefore necessary to suspect and to diagnose pulmonary hypertension as early as possible.Sixty seven patients with systemic sclerosis were retrospectively studied. We compared clinical, immunological, functional (spirometry) and morphological (pulmonary fibrosis) features according to the presence (n = 25) and the characteristic of pulmonary hypertension (isolated or secondary) or the absence (n = 42) of pulmonary hypertension, assessed by Doppler echocardiography.CREST syndrome (calcinosis, Raynaud's phenomenon, oesophageal involvement, sclerodactyly and telangiectasia) was more frequent in patients with isolated pulmonary hypertension than in patients without PH (72.7% vs 28.5%, P0.05; odds-ratio [OR] = 6.6) and dyspnea was more severe (P0.001; OR = 11.4). The age at time of pulmonary hypertension diagnosis was higher in patients with secondary pulmonary hypertension than in patients with isolated from (median: 62.5 years (range: 32-35) vs 53 years (range: 37-85), P0.05). Patients with isolated pulmonary hypertension had anticardiolipin antibodies more frequently than patients without pulmonary hypertension (72.7% vs 35.7%, P0.05). Isolated reduction of diffusing capacity was preferentially observed among patients with isolated pulmonary hypertension than among those without pulmonary hypertension. A linear relation between systolic pulmonary artery pressure values and diffusing capacity values (r = 0.72, P0.01) was found. Isolated reduction of diffusing capacity was more frequent in patients with isolated pulmonary hypertension than in patients without pulmonary hypertension (63.6% vs 14.3%, P0.001; OR = 10.5).The severity of pulmonary hypertension in systemic sclerosis justifies a systematic screening by Doppler echocardiography and diffusing capacity measurement. Our results allow us to better define the characteristics of sclerodermic patients with isolated or secondary pulmonary hypertension. The search for pulmonary hypertension should be repeated with time and clinicians should be particularly vigilant in the case of a patient presenting these characteristics.

There are good reasons to believe that screening of lung parenchymal diseases by CT is superior to chest radiographs. Nevertheless, conventional chest radiography often remains the first examination performed for evaluation of thoracic diseases and, irrespective of clinical indication, it plays an important role in screening procedures. The interpretation methodology of a chest radiograph in a screening condition is reviewed. Specific attention to poor detectability zones is emphasized and a check-list is proposed, mainly to reduce the risk of overlooking lesions. Techniques, indications and respective diagnostic values for both chest radiography and CT scan are analyzed and applied to the screening of lung cancer, asbestos exposure and tuberculosis.

We report the first description of a Sjögren's syndrome associated with nectrotizing sarcoid-like granulmatosis. A 62-year old woman was admitted for diagnostic exploration of fatigue, weight loss, and fever at 38 degrees C which had progressed for more than 3 months. Chest X-ray showed several pulmonary opacities. There was a history of tuberculosis and thyroiditis at the age of 20 years. Physical examination revealed a sicca syndrome. There was no objective evidence of respiratory disease. Her heart and chest were clear on auscultation. The patient had autoantibodies for SSa and SSb specific antigens. Minor salivary gland biopsy gave a score of 3 in the Chisholm classification. Chest X-ray and CT-scan showed diffuse infiltrative opacities which were dense and peripheral with no retraction. Bronchoalveolar lavage, and bronchial and transbronchial biopsies were non-specific. Surgical lung biopsy showed typical aspects of necrotizing sarcoid-like granulomatosis. After high-dose pulse corticosteroid therapy, the opacities disappeared with no recurrence under oral steroids at three years.

Clinical applications of spiral CT angiography are mainly based on transverse CT scans which can be completed by several categories of additional reformations in order to provide the most accurate evaluation of the vessel(s)-of-interest. Two-dimensional reformations are the second most frequent category of reconstructions generated from a spiral data set, enabling the creation of planar (frontal, sagittal or oblique) or curved views of given vessel. Three-dimensional displays can also be generated from most post-processing consoles, namely surface shaded displays (SSD), maximum intensity projections (MIP) and images using the volume rendered technique (VRT). Shaded surface displays are based on a binary selection of voxels using a single or double thresholding whereas MIP images result from the selection of the voxels of highest attenuation value. Volume rendered images are generated by means of a probabilistic classification of voxels consisting of a systematic estimation of the amount of the tissue-of-interest in each voxel. In addition, a variable degree of opacity (or transparency) can be chosen for the vascular structures and/or the surrounding anatomical structures, thus avoiding interpretive difficulties due to superimposition. A fourth category of reconstruction, STS-MIP (i.e., sliding-thin-slab MIP) can be applied to the evaluation of peripheral intraparenchymal vasculatures.

The aim of this study was to provide quantitative data on the origin and trajectory of the main renal arteries using spiral CT angiography and arteriography. Normal renal artery anatomy was assessed on spiral CT angiography (axial transverse sections and shaded-surface-display reconstructions) in 100 patients referred for renal arteriography who had no significant renal artery stenosis. Two hundred major renal arteries were studied. The vast majority of right (88 %) and left (87 %) renal arteries originated between the lower third of the first lumbar vertebra and the lower border of the second lumbar vertebra. In 50 patients both ostia were at the same level; in the remaining 50 patients, the right ostium was located above the left in 37 patients. On the right, the angle of origin varied from -10 to + 55 degrees (mean + 24 degrees ). On the left, the angle of origin varied from + 30 to -55 degrees (mean -11 degrees ). Spiral CT angiography provides additional anatomic data, notably regarding the angle of origin of the renal arteries, that is potentially useful for planning interventional procedures.

It is well known that silica exposure leads in an experimental model to the development of an acute fibrotic process. In human beings two main observations have already been done: (1) silica exposure is frequently associated with the development of connective tissue disease (CTD), especially progressive systemic sclerosis; (2) 10 to 20% patients with CTD developed pulmonary fibrosis. In this context we report 26 cases of coal miners who presented with clinical, radiological, biological and functional characteristics mimicking idiopathic pulmonary fibrosis (IPF), with or without associated coal worker's pneumoconiosis (CWP). All were men; mean age was 68 +/- 9.2 years. Twenty-three were smokers. Duration of exposure was 28.8 +/- 9.1 years. All the patients had dyspnea (stage III, IV in the NHYA classification) and diffuse crackles. Eleven out of 26 had finger clubbing. Computed tomography showed honeycombing (23 cases), and/or ground glass opacities (6 cases) with bronchiectasis (3 cases) predominant in the lower lobes; 19 had radiological signs of CWP, micronodules (n = 16) and nodules (n = 3) predominant in the upper lobes. BAL exhibited an increased % of neutrophils (11.9 +/- 16.1%). Lung function demonstrated a restrictive pattern (TLC = 73 +/- 15.6% and VC = 80 +/- 18% of predicted values) associated with a decreased DLCO (51.8 +/- 23.6% of predicted values) and hypoxemia (at rest = 66.5 +/- 11.2 mmHg, upon effort = 56 +/- 12 mmHg). Lung biopsies were performed in four cases and demonstrated interstitial fibrosis of intraalveolar septum with an accumulation of immune and inflammatory cells similar to the one described in IPF. The association between IPF and silica exposure with or without associated CWP points out the problem of legal recognition of idiopathic-like pulmonary fibrosis as a complication of the occupational exposure of coal workers.

To evaluate the accuracy of spiral CT angiography in the diagnosis of central pulmonary embolism (PE).A retrospective study was undertaken in a population of 90 patients who were evaluated with spiral CT angiography (acquisition: 12 to 24 s with or without strict apnea; injection of 90 cm3 of 12, 20 or 30% contrast material at a rate of 4 to 7 cm3, selective pulmonary angiography of each lung (n = 55) and/or ventilation-perfusion (VP) scanning (n = 35).Among the 55 patients evaluated with both spiral CT and angiography, central pulmonary embolism was excluded in 19 patients (34%), assessed in 29 patients (53%) whereas CT examination was considered as inconclusive in 7 patients (13%) due to interpretive difficulties at the level of obliquely oriented arteries and/or presence of hilar lymph nodes (sensitivity: 90.5%; specificity: 82.6%). With spiral CT, the finding of 95 central emboli (3 main, 61 lobar and 31 segmental) corresponded exactly to the angiographic findings; spiral CT enabled direct visualization of intraluminal filling defects (n = 95) whereas the angiographic recognition of PE was based on direct (n = 57) and indirect (n = 38) signs. Spiral CT angiography was more sensitive and specific than VP scanning.Spiral CT angiography appears as a sensitive and specific noninvasive method for the diagnosis of central PE.

We report a case of a patient of 58 years old who suffered from a left apical opacity occurring in a context of deterioration in general health. Subsequent clinical developments were dominated by the ophthalmic disease and a frontal syndrome. The radiological work-up showed tumoral lesions which had developed from the first rib, from the structures at the base of the cranium and the frontal area and were associated with multiple lacunae of the cranial vault. There was evidence of hyperproteinaemia, and an IgG gamma monoclonal gammopathy, a significant medullary plasmocytosis with morphological anomalies of the plasmocytes leading to a diagnosis of myeloma with a plasmocytoma of the rib and the retro-orbital area. Thoracic disease associated with this pathology is common but mainly present as osteolytic lesions. The occurrence of intrathoracic plasma cell tumours is rarer as are orbital manifestations. In spite of treatment which can frequently lead to an objective response, the prognosis of this disorder remains gloomy.

Spiral scanning (BSV) is a newly acquired scanning technique for all or part of the thoracic volume in a single breath-hold. It offers many advantages when compared to conventional CT scanning. The study of the lungs with a single breath-hold avoids the inconvenience of an anatomical discontinuity while acquiring the information. In a population of patients presenting with multiple, or solitary pulmonary nodules, or the absence of nodule, BSV shows 30 to 40% of supplementary nodules when compared to conventional scanning techniques. BSV enables the optimal use of contrast products in which the iodine is poorly concentrated to study the pulmonary vessels. Certainly this technique will not replace pulmonary angiography for the diagnosis of pulmonary emboli. However, it may be used first in certain situations, dispensing with invasive angiography in patients with an increased risk, or in the initial assessment of patients with pulmonary arterial hypertension of unknown aetiology, or to follow a previously documented pulmonary emboli. The correlation between spiral scanning and conventional angiography for the diagnosis of pulmonary emboli is excellent, to the level of segmental arteries. Finally the continuity, both anatomically and for the lesions obtained by BSV is such that it is now possible to apply to thoracic pathology techniques of multiplanar and three dimensional reconstruction. If all the information is contained in conventional transversal imaging slice by slice, not everything is perceived by the observer because the information is inconveniently presented because the anatomical and lesional picture is deconstructed. The reconstruction of the volume inspected in coronal, sagittal, oblique or three-dimensional viewing, furnishes supplementary information and announces the arrival of trachea-bronchography, and non-invasive angiography three-dimensionally. In parallel to the expected progress in IRM angiography, three-dimensional angio-CT of the thoracic vessels after appropriate evaluation is going to be substituted for more invasive techniques which are currently used.

In order to better define the outcome of patients with neonatal congenital diaphragmatic hernia (CDH), 17 patients between 3 and 19 years of age, among 34 survivors from 100 CDH have been re-examined clinically. All had a lung radiography, lung function studies, and radionuclide (Technetium 99m, Xenon 133) lung scans. Three patients suffered from asthma, 2 had recurrent bronchitis, 4 poor tolerance to effort, 3 gastrooesophageal regurgitation leading to endobrachyoesophagus and oesophagitis in one, 3 had scoliosis. Lung scans demonstrated hypoperfusion of the herniated side (less than 40%) in 6 patients. Chest films showed hypovascularisation on the herniated side. Lung function studies, performed in 4 of these 6 patients, showed a restrictive syndrome in 1 patient. Our results confirm those in the literature: perfusion is more altered than ventilation. Chest films at one year of age, completed if necessary by radionuclide lung scans, allow identification of children who have important pulmonary hypoplasia. These children need a regular follow-up: respiratory, digestive and orthopedic complications must be treated in order to preserve the respiratory function in adulthood.

Systemic diseases such as scleroderma (ScI), rheumatoid polyarthritis (PR), Gougerot-Sjögren Syndrome (GS) have a well known propensity for the lungs. Previous studies have shown evidence of disturbed alveolar cell repair as evidence of a sub-clinical alveolitis. The significance of such cases of latent alveolitis remains to be specified. To determine if latent alveolitis was associated with interstitial chest disease which was undetectable by chest X-ray, 36 consecutive patients had an BAL and a high resolution computered tomographic examination (HRTC) (Scl: n = 21; PR: n = 9; GS: n = 6). The patients had normal respiratory function and chest X-ray was normal. Our results showed 17 out of 36 (47%) with a latent alveolitis (the percentage of lymphocytes and of alveolar polymorpho-nuclear neutrophils was superior or equal to 18 and 4% respectively) (Scl: 12/21; PR: 1/9; GS: 4/6). In the cases of scleroderma a neutrophil alveolitis was predominant (9/12) and was associated in 2 cases with a honeycomb lung and evidence of fibrotic lesions using TDM-HR. Those examinations using HRTC which were normal were equally associated with a latent alveolitis (Scl: 6/12; PR: 1/6; GR: 4/5). These results suggest that the alveolitis can preceed the anatomical damages. These results need to be confirmed in a larger series and the value of early treatment should be evaluated.

The authors report a case of congenital absence of the left pericardium in a pauci-symptomatic young woman. Indirect signs in favour of this diagnosis were elicited on chest X-ray (levoposition of the heart, convex left heart border). An associated congenital heart lesion was excluded by Doppler echocardiography. Computed tomography and MRI showed the right pericardium to be present but the left pericardium (not always visible in normal subjects) and the pre-aortic recess (present in all normal subjects) were absent. Abnormal presence of lung tissue between the aorta and pulmonary artery, and also between the pulmonary artery and left auricle was, however, confirmed. Nevertheless, these investigations did not enable the authors to define the exact extent of the pericardial defect. Finally, the indirect signs of levocardioposition were the main diagnostic markers of congenital absence of the left pericardium which did not require surgery in this particular case.

The non bronchial systemic arterial circulation of the lung may, for more than one good reason, be considered as a third arterial circulation of the lung, after the bronchial and pulmonary circulation. A perfect knowledge of the anatomy of the circulation and the physiopathological mechanisms leading to its development is a vital prelude to angiographic study. A common point in the majority of situations leading to this non bronchial systemic arterial hypervascularization is the existence of a pleural symphysis allowing the pulmonary penetration of these thoracic parietal vessels. In addition to the contribution of the transpleural non bronchial systemic vessels the role of the arteries of the triangular ligament should be discussed. The pathological significance of this non bronchial systemic hypervascularization is threefold. This circulation can be the source of haemoptysis as shown by angiography and is important for considering therapy when haemoptysis needs treatment by percutaneous embolisation. The duration and the risk of catheterisation may be considerably reduced thanks to the precision of the endoscopic examination at the site of bleeding. There are other types of endothoracic haemorrhage which can be qualified as "haemoptysis like" whose treatment, preventative or curative may also be assured by embolisation of this circulation. Besides a certain number of extracardiac shunts both endo and transthoracic, without any haemorrhagic consequence at the time at which they are discovered show evidence of abnormal communication between the three circulations of the lung; certain of these may need therapy by vaso-occlusion.

Forty two pulmonary arteriovenous malformations (PAVM) in seventeen patients were treated by coil vaso-occlusion between 1979 and 1989. The techniques of deposition of coils and spiders and the precautions taken to avoid complications are described. Complete occlusion of the arterial pedicles of the PAVM was immediately obtained in 34/37 pedicles. 3/37 were occluded secondarily. Five PAVM were submitted to surgery demonstrating the reciprocal indications for surgical and per-angiographic techniques. Except in one patient, in the beginning of our experience, the observed complications were minor and we have subsequently modified our techniques to avoid them.

Objectifs Dresser le bilan des avancees technologiques et evaluer leur impact sur l’imagerie medicale. Materiels et Methodes Les principaux facteurs de progres sont passes en revue : nombre de coupes par rotation, collimation, temps de rotation, economie d’irradiation, algorithmes de correction des artefacts, reconstructions ciblees et orientees, detections automatiques de lesions, analyse de vaisseaux. Partant de la generation 2004, les principaux parametres emanant de donnees constructeurs et utilisables dans les prochaines annees sont analyses, selon les informations recues. Resultats Le gain en resolution spatiale de voxels isotropiques est programme a 0,2 x 0,2 x 0,2 mm. Mais il ne peut etre exploite que par la maitrise des mouvements physiologiques, donc des temps de balayage, circulaire ou spirale. Les effets de la transformation de la geometrie conique des faisceaux restent a evaluer de meme que ceux des sur-echantillonnages dans l’axe Z, indispensable pour installer l’imagerie de perfusion dans certains organes. Il reste egalement a demontrer que les tres grandes rapidites d’acquisition seront benefiques aux applications cliniques. Conclusion De fascinants progres s’annoncent dans une imagerie medicale morpho-fonctionnelle de haute precision.

Pulmonary involvement was investigated by High Resolution Computed Tomographic scan (H.R.C.T.), bronchoalveolar lavage (B.A.L.) and pulmonary fonction tests (P.F.T.) initially and in the follow up of 42 patients with progressive systemic sclerosis: B.A.L. was more sensitive than H.R.C.T. or P.F.T. to assess lung involvement in P.S.S., although not correlated with disease severity. H.R.C.T. is the method of choice for evaluation of parenchymal destruction.