[Idiopathic interstitial pneumonitis presenting with Wells grade III. Can imaging methods help predict further progression of disease?]

PURPOSE

Three different grades of idiopathic pulmonary fibrosis can be identified by HRCT pattern. Patients with predominant ground-glass opacity (grade I) usually improve after treatment and may have a better prognosis. The subjects with a predominant reticular pattern and honeycombing (grade III) have irreversible fibrosis and usually do not improve after immunosuppressive therapy. Nevertheless, these patients may worsen even in the absence of HRCT features of the so-called alveolitis. We investigated the predictive role of some noninvasive imaging methods (HRCT with visual score of disease extent; Gallium scintigraphy; DTPA scintigraphy) in patients with idiopathic fibrosis and a prevalent macroscopic fibrosis at HRCT study.

MATERIAL AND METHODS

Fourteen former smokers with grade III idiopathic fibrosis were examined. None of the patients had been treated. They were all submitted to HRCT, lung function studies, Gallium and DTPA scintigraphy, both at presentation (T0) and follow-up sessions (T1: mean one year post-diagnosis). The HRCT extent of disease was evaluated by means of the visual score as the fraction of the total lung volume. The patients were divided into two groups, using a cut-off value of 50%. All the patients underwent a Gallium scintiscan (using a fixation index of 160 as cut-off) and a ventilatory scintigraphy with DTPA-aerosol, with radionuclide clearance assessment. The lung function tests considered were vital capacity (VC), arterial blood oxygen partial pressure (PaO2) and the diffusing lung capacity for carbon monoxide (DLCO).

RESULTS

After one year of follow-up, the HRCT extent score increased (from 46.6% to 50%) and lung function worsened (VC from 66.8% to 63.4% of predicted; DLCO from 37.6% to 27.1%; PaO2 from 77 to 71 mmHg). The patients presenting with HRCT extension score > 50% had a worse lung function at T0 and showed a significant deterioration of PaO2 and HRCT at T1. On the other hand, VC and DLCO significantly worsened in the subjects with HRCT score < 50% at presentation. The patients with a Gallium fixation index > 160 significantly deteriorated in HRCT score, VC and DLCO. Those with Gallium index < 160 had major worsening only for diffusing lung capacity for carbon monoxide. Thirteen of 14 patients had an abnormal value of DTPA clearance at presentation. No variation was observed at T1.

DISCUSSION AND CONCLUSIONS

The majority of patients with idiopathic fibrosis are grade III at presentation. They can further deteriorate both in HRCT extent of disease and lung function impairment. After one year of follow-up HRCT extent score increased in 64% of the patients, with a mean increase of 5%. HRCT worsening was more apparent in the patients with a HRCT score > 50% at presentation. In the remaining patients, the worsening of lung function tests was more apparent than the anatomoradiological changes. DTPA clearance had no predictive value in this series. Gallium scintigraphy was a useful prognostic index. The patients with Gallium fixation index > 160 had better lung function and lower HRCT extent score at T0 but significantly deteriorated at T1. A positive Gallium scan at presentation could be considered a useful index of persisting active "alveolitis" in patients with grade III disease, not visible at HRCT study, due to overwhelming fibrosis. These patients, who were untreated, exhibit quicker radiological and functional worsening.

Clinical spectrum of adult chronic bronchiolitis

Inflammation involving the small airways is a quite common report in pathological dissertations. However the radiologic, clinical patterns and functional impairment of adult bronchiolitis have been discussed in detail only in the last ten years. In this review a brief summary of the anatomic and histologic characteristic of small airways is reported. A pathologic classification of bronchiolitis is at first discussed. Cellular bronchiolitis, proliferative bronchiolitis with or without intraalveolar loose fibrosis (BOOP pattern), occlusive and constrictive bronchiolitis are the main patterns taken into account: peculiar subtypes (follicular bronchiolitis, diffuse panbronchiolitis, neuroendocrine cell hyperplasia with fibrous bronchiolitis) are included in the pathologic discussion. Radiologic features are reported and presented as nonspecific. HRCT Scan findings are classified with the appropriate pathologic features in: nodules and branching lines; low attenuation and mosaic perfusion; ground glass attenuation and/or alveolar consolidation. The clinical entities considered are: bronchiolitis secondary to irritant inhalation; infectious and post-infectious bronchiolitis; drug induced bronchiolitis; bronchiolitis in patients with collagen-vascular disease; diffuse panbronchiolitis; bronchiolitis in transplanted patients; neuroendocrine cell hyperplasia with fibrous bronchiolitis: cryptogenic bronchiolitis; idiopathic BOOP; respiratory bronchiolitis with interstitial lung disease (RB-ILD). Their clinical presentation, functional impairment, pathogenetic mechanisms when deemed clinically useful, BAL findings and therapeutical schemes are discussed.

Diagnostic role of gallium scanning in the management of lymphoma with mediastinal involvement

BACKGROUND AND OBJECTIVE

Therapy of both Hodgkin's disease (HD) and aggressive non-Hodgkin's lymphoma (NHL) with mediastinal presentation at the time of diagnosis is frequently followed by radiological detection of residual masses. Computed tomography (CT) scanning is generally unable to detect the differences between tumor tissue and fibrosis. Gallium-67-citrate single photon emission ((67)GaSPECT) can potentially differentiate residual active tumor tissue from fibrosis.

DESIGN AND METHODS

Seventy-five patients with HD or aggressive NHL presenting mediastinal involvement (64% with a bulky mass) were studied with CT and (67)GaSPECT at the end of combined modality therapy (chemo- and radiation therapy).

RESULTS

After treatment, 3/3 (100%) patients with positive (67)GaSPECT and negative CT scan relapsed while only 1/18 (6%) patients with both negative (67)GaSPECT and CT scan did so. At the same time, 54 patients had a positive restaging CT scan (abnormal mass < 10% of size of initial mass). Of these patients, 13 had a positive (67)GaSPECT, 10 of whom (77%) relapsed; 41 had a negative (67)GaSPECT of whom 5 (12%) relapsed. The 4-year actuarial relapse-free survival rate was 90% for those with negative scans compared with 23% for gallium-positive patients (p < 0.000000).

INTERPRETATION AND CONCLUSIONS

In lymphoma patients with mediastinal involvement, (67)GaSPECT should be considered, at least in patients who are CT positive, the imaging technique of choice for monitoring and differentiating the nature of any residual masses.

Bronchoalveolar lavage and transbronchial lung biopsy in alveolar and/or ground-glass opacification

In order to assess the diagnostic yield of bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBB) in pulmonary diseases with a ground-glass and/or alveolar pattern on high-resolution computed tomography (HRCT) scan, a prospective study was undertaken. Thirty-six patients (17 males, 19 females), mean age 53 yrs, selected on the basis of the presence of an alveolar and/or ground-glass pattern on chest HRCT scan, were submitted to fibreoptic bronchoscopy. All patients underwent BAL. TBBs were performed in 33 cases. A specific diagnosis was achieved, taking into account data obtained by means of serology, microbiology, cytology and histopathology in appropriate clinical settings. Twelve (33%) patients only had the appearance of a ground-glass opacity, whereas 24 (67%) had associated areas of airspace consolidation. BAL was performed in all cases and gave a definitive diagnosis in 21 (58%). The diagnostic yield of BAL in patients with only ground-glass opacities was no different from that in those patients also showing areas of alveolar consolidation (58 versus 58%). In eight patients (six with ground-glass opacity and two with alveolar consolidation), BAL provided useful but not definitive information. In these patients, a definitive diagnosis was achieved by means of TBB in seven cases and by open lung biopsy in one case. TBB was performed in 33 out of 36 patients and gave positive results in 25 (76%). The diagnostic yield of TBB in patients showing areas of alveolar consolidation was significantly higher than in those with pure ground-glass opacity, i.e. 95% (21 of 22) and 36% (4 of 11) respectively (p < 0.001). BAL and TBB were performed during the same bronchoscopy in 33 patients, and an accurate diagnosis was achieved in 30 (91%). Overall, the diagnostic yield of TBB (76%) and BAL (56%) did not differ significantly in the whole patient group (p = 0.12), or in patients with a ground-glass opacification (58 versus 36%, p = 0.3). However, in patients with areas of alveolar consolidation, the diagnostic sensitivity of TBB (95%) was significantly greater than the diagnostic sensitivity of BAL (54%) (p = 0.03). In conclusion this study shows that high-resolution computed tomography can be helpful in predicting the diagnostic accuracy of bronchological procedures, in particular of bronchoalveolar lavage and transbronchial biopsy, and that alveolar and/or ground-glass are favourable patterns for these diagnostic tools.

[Role of emphysema in the etiology of functional impairment in patients with severe chronic obstructive pulmonary disease. Study with high resolution computerized tomography]

PURPOSE

To investigate whether high-resolution CT (HRCT) can detect the subjects with massive emphysematous destruction in a group of patients with severe chronic obstructive pulmonary disease (COPD) and therefore be of help in selecting the candidates to surgical lung volume reduction.

MATERIAL AND METHODS

We examined 40 former smokers with severe COPD (FEV1, < or = 40% of the predicted value, with no major improvement after inhalation of bronchodilators). Clinico-functional assessment included: a flow/volume loop (mean FEV1 = 28.6% of predicted), arterial blood gas analysis at rest breathing room air (mean values: PaO2 = 65.2 mmHg, PaCO2 = 47.4 mmHg), hematocrit value (mean: 45.2%) and the body mass index (mean value: 23.8). The patients were divided into two groups, namely bronchitic (21) and dyspneic (19) subjects, according to onset symptoms. All the patients underwent HRCT with evaluation of emphysema presence, type, site and extent: centrilobular emphysema was seen in 11 cases, panlobular emphysema in 3 and mixed emphysema in 26 cases; the site was superior in 75%, inferior in 7.5% and diffuse in 17.5% of cases; the mean visual score was 40.8%. The presence, type, site and severity of airways disease were also studied, as well as the pathologic dilatation of the pulmonary artery. The patients were divided into three groups (mild, moderate, severe) according to emphysema extent and they were considered to have bronchial disease in the presence of at least 2 of the 6 signs of bronchial involvement.

RESULTS

The emphysema extent score was significantly correlated with the hematocrit value and Tiffeneau index (p < .2) in all the 40 patients. The severity of bronchial obstruction was the same in bronchitic and dyspneic patients. The subjects with chronic bronchitis had milder emphysema (mean extent 35% versus 47% in the dyspneic subjects) and a higher frequency of bronchial involvement. A decrease in FEV1 was significantly correlated with emphysema extent (p < .1) in dyspneic, but not in bronchitic, patients. Moreover, the former had better arterial blood gas and lower hematocrit values.

CONCLUSIONS

HRCT is a useful tool in diagnosing the presence of emphysema in vivo and in assessing its extent in COPD patients because it permits to divide the patients into two groups which roughly correspond to the clinical patterns of types A (dyspneic) and B (bronchitic). Severe emphysema patients are the best candidates to surgical lung volume reduction. Airways involvement might play a major role in causing bronchial obstruction in the subjects with mild emphysema. In our series HRCT did assess the severity of emphysema in COPD subjects, but our lung function screening failed to predict emphysema extent.

[Course of idiopathic pulmonary fibrosis of the Wells grade III at presentation. Study using high-resolution computerized tomography]

PURPOSE

We studied the HRCT and functional evolution of idiopathic pulmonary fibrosis (IPF) patients presenting with Wells grade III--prevalent fibrosis.

MATERIAL AND METHODS

We sequentially studied the HRCT and functional findings of 16 IPF patients, at presentation and at 1 year. All patients had a typical grade III IPF pattern; those with the most severe clinical presentation were treated (9/16). The main HRCT parameters were the extent of interstitial involvement and emphysema (visual score) and the mean diameter of lung cysts in honeycombing regions.

RESULTS AND CONCLUSIONS

Most of our grade III IPF patients exhibited a slowly progressive deterioration, with no accelerated parenchymal opacification. Deterioration was found on HRCT images in 56.2% of patients (p = .02), with a mean monthly increase of .56%. Fibrosis extent, evaluated as HRCT visual score at presentation, was significantly correlated with viability and PaO2, values (p = .01). Follow-up HRCT scores were also significantly correlated with viability (p = .004). The mean diameter of honeycomb lung cysts increased in 25% of patients. Emphysema was associated at presentation in 50% of patients--all of them former smokers; it was less diffuse than interstitial involvement (15% of total lung volume versus 46.7% at presentation) and was not seen to progress on follow-up images. The comparison between treated (T) and untreated (NT) patients confirmed more severe HRCT and functional damage in T patients at presentation. Moreover, T patients presented a significantly more rapid deterioration, despite treatment, than NT patients, who had less severe and slower HRCT and functional evolution, excluding DLCO deterioration (p = .01). To conclude, grade III IPF patients can be subdivided into two subgroups, with rather different prognosis and evolution, on the basis of HRCT and functional findings at presentation. The current treatment seems useless in grade III IPF. HRCT findings, integrated with the visual score of disease extent, and lung function tests can be used to monitor grade III IPF evolution.

[Dynamic computed tomography in the study of bronchiolitis obliterans]

Obliterative or constrictive bronchiolitis is characterized by narrowing of the small airways, due to submucosal and peribronchiolar fibrosis, with chronic obstruction. The vast majority of cases of bronchiolitis obliterans are associated with other diseases and only few cases are idiopathic. We report on the main computed tomography (CT) methods used study obliterative bronchiolitis, the CT findings and the differential diagnosis with other diseases. The dynamic study of alveolar ventilation with CT uses inspiratory and expiratory CT or high-resolution CT (HRCT), spiral dynamic CT or HRCT with advanced image display, ultrafast CT. In abnormal cases HRCT shows direct and indirect signs of small airways disease. The most common (> 80%) sign of obliterative bronchiolitis is the so-called mosaic oligohemia, with low attenuating lobules, caused by air trapping and best seen on expiratory CT, associated with blood flow redistribution to more normal lobules; this finding simulates the ground-glass pattern from infiltrative lung disease. Differential diagnosis is more difficult in the presence of true ground-glass patterns associated with diffuse bronchiolar obstruction and also with mosaic oligohemia due to pulmonary vascular disease and pulmonary emphysema. HRCT can distinguish these diseases and dynamic CT is more sensitive than functional tests in detecting regional abnormalities and air trapping. The combination of HRCT, rapid volumetric scanning and advanced image display is a powerful tool study the normal and abnormal features of bronchiolar function and alveolar ventilation.

Imaging of small airways disease, with emphasis on high resolution computed tomography

Bronchioles are the airways less than 2-3 mm in diameter. Normal bronchioles cannot be reliably detected by means of high resolution computed tomography (HRCT). Nevertheless, in pathological cases, bronchiolar lesions can be identified by taking into account direct and indirect signs. On radiological grounds, bronchiolar lesions can be classified into four groups, on the basis of HRCT findings: 1) prevailing nodular opacities and "tree in bud" pattern; 2) consolidations or ground-glass opacities; 3) mosaic oligosemia with expiratory air-trapping; and 4) mixed cases. In this review, we present the main radiological and HRCT findings in four different entities, representing the more typical cases of bronchiolar pathology; bronchiolitis obliterans; bronchiolitis obliterans with organizing pneumonia; diffuse panbronchiolitis; and respiratory bronchiolitis with associated interstitial lung disease. HRCT sometimes allows a precise diagnosis of bronchiolar pathology; however, more often, it permits only a range of hypotheses to be advanced. More importantly, it allows a precise localization for biopsy procedures and an exact follow-up after institution of therapy. In normal subjects, less than 1% of the whole bronchial tree is visible on the standard chest radiograph. HRCT offers a good insight and invaluable information. New techniques, such as volumetric HRCT with sliding-thin-slab maximum- and minimum-intensity projections (MIP and minip) could represent an important additional tool in the evaluation of small airways disease.

Assessment of the severity of pulmonary emphysema by computed tomography

Pulmonary emphysema is defined as an abnormal enlargement of alveolar spaces distal to the terminal bronchioles, with alveolar wall disruption and without obvious fibrosis. Clinico-functional evaluation and chest radiographic diagnosis are not highly accurate in detecting emphysema and in establishing the extent of the process of alveolar destruction. Several computed tomography (CT) techniques are now available for detection and quantitative assessment of emphysema. The results appear to correlate significantly better than chest radiography with functional impairment and pathological score. Many options have been proposed by different authors regarding CT technique. The choice, however, is essentially between inspiratory high resolution CT (HRCT) with a visual scoring system, and automated quantitative evaluation by means of a "density mask" (DM) program. This paper presents the state of the art on CT quantification of pulmonary emphysema and briefly discusses the technical options and parameters to be used, together with the problems to be solved.

[Quantitative assessment of pulmonary emphysema with computerized tomography. Comparison of the visual score and high resolution computerized tomography, expiratory density mask with spiral computerized tomography and respiratory function tests]

CT is the most accurate method to detect pulmonary emphysema in vivo. We compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. The type and extent of pulmonary emphysema were defined, using the time-honored visual score system, by two independent observers under blind conditions. Disagreements were subsequently settled by consent. All subjects were also examined with expiratory spiral CT, using a density mask program, at two different cut-off levels (-850, -900 HU). Visual score and expiratory spiral density mask values (-850 HU) were significantly correlated (r = 0.86), but the visual extent of emphysema was always higher than shown by expiratory spiral CT. The emphysema extent assessed with both CT methods correlated with the function result of expiratory airflow obstruction and gas diffusion impairment (visual score versus forced expiratory volume in one second: r = -0.81, versus single breath carbon monoxide diffusion: r = -0.78. Spiral expiratory density mask -850 HU versus forced expiratory volume in one second: r = -0.85, versus single breath carbon monoxide diffusion: r = -0.77). When -900 HU was used as the cut-off value for the expiratory density mask, the correlation with single breath carbon monoxide diffusion worsened (r = -0.56). Visual score and expiratory density mask -850 HU gave similar results and permitted COPD patients to be clearly distinguished from normal controls (p < 0.01). Residual lung volume, measured with expiratory spiral CT correlated significantly with residual volume measured with the helium dilution technique (r = 0.66), but CT values were always higher than function results. We believe the true residual volume should lie somewhere in between the CT value and the function results with the helium dilution technique and conclude that the extent of pulmonary emphysema can be confidently assessed with CT methods. Finally, the simple visual score may be as reliable as such highly sophisticated new methods as the spiral expiratory density mask. Expiratory studies offer new insights into different normal and abnormal features of COPD and respiratory impairment.

Thoracic complications in uremic patients and in patients undergoing dialytic treatment: state of the art

No organ in the chest is spared the negative effects of uremia. The dialytic treatment itself is often associated with a large array of thoracic complications. We review the main thoracic manifestations of the terminal uremia from the radiological point of view, such as: uremic pleuritis and pericarditis, uremic pneumonia, renal osteodystrophy, infections, and metastatic pulmonary calcifications. Respiratory function derangement and the problems related to peritoneal dialysis and hemodialysis are discussed in some detail, along with the diagnostic role of plain films, US, nuclear medicine, and CT. The main focus of this review is on the hydration problems and pulmonary edema, often related to a large number of pathogenetic factors. Based on our experience, we think that the chest X-ray is not able to accurately discriminate between cardiogenic edema and fluid overload edema (so-called renal pulmonary edema). The radiological findings of the thoracic complications in uremic patients are multiple and complex but, in most cases, the imaging techniques may offer an accurate and noninvasive diagnostic approach, with a high benefit-cost ratio.

Hemodynamic estimation of chronic cor pulmonale by Doppler echocardiography. Clinical value and comparison with other noninvasive imaging techniques

Pulmonary arterial pressure (PAP) represents an important prognostic factor in patients affected by chronic obstructive pulmonary disease (COPD). A noninvasive diagnostic approach is offered by several imaging techniques, such as chest X-ray, nuclear medicine, real-time sonography, color Doppler US, CT and MRI. However, at present a quantitative assessment of PAP is not achieved with reasonable precision with any of these techniques. Tricuspid regurgitation can be estimated by continuous wave Doppler but it may be difficult in patients with COPD. On the contrary, the severity of pulmonary hypertension can be accurately assessed with pulsed Doppler echocardiography from the subxiphoid region, using a general purpose US device. Nineteen adult patients with COPD were studied by duplex-Doppler from an oblique subxiphoid approach and right heart catheterization. The study was diagnostic in all cases with quality Doppler recordings. A significant relationship was found between AcT and pulmonary mean or systolic pressure at rest. An accurate prediction of PAP in COPD is possible by means of pulsed-Doppler also in low-grade hypertension. This technique is considered a simple and reliable adjunct to the noninvasive evaluation of COPD and represents a satisfactory alternative to the classical parasternal approach preferred by cardiologists but often not suitable for emphysematous patients. Radiologists who routinely use a general purpose US device are encouraged to try this new technique in the study of heart disease.

The diagnostic value of bronchoalveolar lavage and transbronchial lung biopsy in cryptogenic organizing pneumonia

In order to determine the diagnostic value of bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB) in cryptogenic organizing pneumonia (COP) a prospective study was carried out. Thirty seven consecutive patients (20 males and 17 females) with clinicoradiological features of COP were enrolled in the study. The statistical analyses were completed in 35 cases. Twenty eight patients were diagnosed to have COP, all of them with a confirmatory biopsy. In seven cases, a different diagnosis was made. BAL cytological and phenotypical criteria considered for the diagnosis of COP were: a lymphocytosis of more than 25% (with a CD4/CD8 ratio less than 0.9); combined with at least two of the following data (foamy macrophages of > 20%, and/or neutrophils of > 5%, and/or eosinophils of > 2% and < 25%). TBLB specimens were classified as positive for COP if they showed: buds of granulation tissue within the centrilobular air spaces; infiltration of alveolar walls with chronic inflammatory cells; and preservation of alveolar architecture. BAL was performed in 34 patients; 17 cases were consistent with the final diagnosis of COP (sensitivity 63%), and four cases were correctly classified as negative (specificity 57%). BAL had a positive predictive value (PPV) of 85% and a negative predictive value (NPV) of 29%. TBLB was performed in 32 patients; it correctly identified COP in 16 cases (sensitivity 64%), and six cases were correctly classified as negative (specificity 86%). TBLB had a PPV of 94% and a NPV of 40%. The accuracy of the examinations, that is the probability of correctly diagnosing both diseased and nondiseased patients by BAL or TBLB, was 62 and 69%, respectively. Our findings suggest that the combination of cytological bronchoalveolar lavage and histological transbronchial lung biopsy data obtained during a fibreoptic procedure appears to be an effective method for the initial investigation in cryptogenic organizing patients pneumonia presenting with patchy radiographic shadows.

[Bronchial involvement in sarcoidosis. Study with high resolution computerized tomography]

We investigated the HRCT findings of bronchial abnormalities in thoracic sarcoidosis, the post-treatment reversibility of such patterns and their specificity for sarcoidosis. Sixty-one sarcoidosis patients were submitted to chest radiography and HRCT at onset. The diagnosis had transbronchial biopsy confirmation in all patients. HRCT was repeated in 21 patients after a cycle of steroid therapy. Sarcoidosis patients were randomized with 29 patients with diffuse infiltrative lung diseases of different nature. The HRCT findings of bronchial abnormalities follow: extrinsic bronchial compression or displacement by lymphadenopathies (regular/irregular), bronchial wall thickening (regular/irregular), bronchial lumen abnormalities, traction bronchiectasis and bronchiolectasis. Bronchial abnormalities were found in the first HRCT study in 44/61 sarcoidosis patients (72.1%), in 18 patients with extrinsic bronchial compression or displacement by lymphadenopathies (40.9%), in 2 with bronchiectasis or bronchiolectasis (4.5%) and in 24 with one or more other abnormalities (54.5%). Bronchial signs were found in 16/21 patients examined with HRCT after steroid therapy (76.1%). Bronchial abnormalities remained unchanged in 11 patients (68.7%), they improved or disappeared in 5 patients (31%) and appeared ex novo in 2 patients. HRCT patterns of bronchial abnormalities were found in 17/29 patients with other diseases (58.6%), with high rates of bronchial wall thickening and bronchiectasis or bronchiolectasis. The most common HRCT bronchial finding in sarcoidosis was extrinsic bronchial compression of displacement by lymphadenopathies. This was the only sign which could actually differentiate sarcoidosis from other patients (p < 0.01). Other signs (bronchial lumen abnormalities and bronchial wall thickening) were frequently found in both sarcoidosis and non-sarcoidosis patients and did not permit to distinguish the former from the latter. In our experience, HRCT findings of bronchial abnormalities were frequently observed in sarcoidosis patients, but they are not specific enough to diagnose sarcoidosis and their usefulness is limited in predicting posttreatment reversibility (activity evaluation) of this condition.

Monitoring bulky mediastinal disease with gallium-67, CT-scan and magnetic resonance imaging in Hodgkin's disease and high-grade non-Hodgkin's lymphoma

Treatment of both Hodgkin's disease (HD) and high-grade non-Hodgkin's lymphoma (HG-NHL) with bulky presentation at diagnosis frequently results in residual masses detected radiologically. Conventional diagnostic radiology and computed tomography (CT) are generally unable to detect the differences between tumor tissue and fibrosis. Gallium-67-citrate (67Ga) SPECT and magnetic resonance imaging (MRI) can potentially differentiate residual active tumor tissue and fibrosis. Thirty-three patients with HD or HG-NHL presenting with bulky mediastinal disease were studied with CT, 67Ga SPECT, and MRI (only for 16 patients) at diagnosis, after two-thirds of their chemotherapy, at the end of chemotherapy, and after radiotherapy in order to evaluate the mediastinal region on the basis of persistence of residual masses and activity of pathological tissue. After treatment, all patients with 67Ga-negative (30/33) disease are still in continuous complete response. Among the three 67Ga-positive patients, 2 relapsed within one year and another one is still alive without evidence of disease. Regarding MRI, two patients were found to be positive, one of them concomitant with 67Ga-positivity; both patients survive in complete response. In lymphoma patients with bulky mediastinal presentation, the 67Ga SPECT remains the preferable imaging technique for monitoring and differentiating the eventual active residual tumor. In combination, CT and 67Ga SPECT represent a suitable complete imaging approach to the radiological diagnosis which may be useful in these particular patients. MRI could probably be considered as a second-line method and from our data would be used only in selected cases because of the high cost, accessibility, and lower specificity as opposed to 67Ga SPECT in evaluating potentially active residual disease.

[The assessment of the activity of idiopathic pulmonary fibrosis by high-resolution computed tomography]

The authors report the results of the study performed with high resolution CT (HRCT) in a group of 29 patients affected with idiopathic pulmonary fibrosis (IPF). Each patient underwent HRCT at the beginning of the study and after one year. A complete clinico-functional assessment was available in 20 cases and functional CT correlation was made in these patients; 15/20 subjects underwent immunosuppressive therapy with corticosteroids and cyclophosphamide. Disease severity was assessed with chest radiography and HRCT. On the basis of CT findings the patients were classified into three groups, according to Wells classification: predominant ground-glass pattern, mixed pattern and predominant reticular disease with honeycombing. Furthermore, a visual score was assigned to total disease extent and a different score to ground-glass and reticular opacities. Our data confirm the poor accuracy of chest radiography in assessing disease type and overall severity, versus the outstanding diagnostic accuracy of HRCT. We also found a high incidence of mediastinal adenopathies (37.9% of the patients) and signs of pulmonary arterial hypertension (62%), together with low extent of pulmonary emphysema (65.5% of the patients; mean extent: 5.4%). Ground-glass attenuation is an early sign of IPF and might suggest alveolitis activity. In our series, however, the patients with grade I disease were rare (6.8%), but likely to benefit from therapy. Different from Wells, we found no significant difference in the evolution of the patients with grade II versus grade III disease. Wells grading was useful in early disease assessment, but the visual score of total disease extent and the score of ground-glass and reticular opacities were much more useful in the follow-up because they can assess disease progression. Furthermore, in the few patients with predominant alveolitis, who improve after therapy, the relative prevalence of the reticular pattern might allocate the patient in a higher Wells group with a "paradoxical" worsening, if the visual score of the extent of the primary lesion is not used.

Posttraumatic chyluria due to lymphorenal fistula regressed after somatostatin therapy

A sudden-onset chyluria after trauma was evaluated giving evidence of a lymphatic-urinary fistula in the right kidney. Treatment with somatostatin normalized the urinary pattern and the result was maintained even after the discontinuation of the therapy.

[Bulky mediastinal lymphomas: role of magnetic resonance and SPECT-Ga-67 in the evaluation of residual masses]

A residual mediastinal mass is a common finding during and/or after treatment for bulky mediastinal lymphoma and represents a difficult diagnostic problem. For correct therapy modulation, fibrosis must be distinguished from active disease. To assess diagnostic imaging potentials in the characterization of residual masses, 41 patients with bulky mediastinal lymphoma were examined with CT, MRI and Ga67-SPET; 92 examinations were performed for each technique: 14 before treatment, 42 during and after chemotherapy, 13 after radiotherapy and 23 six months after the end of treatment. CT provides useful pieces of information on tumor size but fails to depict tissue changes: therefore, only MR and SPET results were considered and compared with clinico-biological and follow-up findings. MRI and SPET were often in agreement with each other (78/92 cases) and with clinical data (98.7%); each examination yielded only one false positive. In case of disagreement (14/92 patients), MRI yielded more false-positive findings because it failed to differentiate neoplastic tissue from treatment-related conditions, i.e., granulation tissue, inflammation, necrosis, early fibrosis. In contrast, negative MR results were more reliable, MR negative predictive value being 100%. Ga67-SPET exhibited high sensitivity (97.1%) and specificity (91.2%), with fewer false positives than MRI (5 vs. 10). In conclusion, both examinations were accurate in the characterization of residual mediastinal masses during and after therapy, but MRI had higher sensitivity and Ga67-SPET higher specificity. Therefore, the authors acknowledge the complementary role of these two techniques and the necessity of an integrated approach, i.e., combined MRI and Ga67-SPET or CT and Ga67-SPET.