Visual and Automated CT Measurements of Lung Volume Loss in Idiopathic Pulmonary Fibrosis.

OBJECTIVE. The purpose of this study is to establish the relationship between CT markers of lung volume and pulmonary function test (PFT) parameters of lung volume in idiopathic pulmonary fibrosis (IPF). MATERIALS AND METHODS. The relationships between PFT-derived parameters of lung volume (forced vital capacity [FVC] and total lung capacity [TLC]) and both CT-derived automated lung volume and manually derived surrogate measurements of lung volume on CT were evaluated in 273 patients (212 men and 61 women; median age, 67 years) with a multidisciplinary diagnosis of IPF. All patients underwent unenhanced volumetric high-resolution CT of the thorax. Automated lung volume was extracted using commercially available software. Three manual CT surrogate measurements of lung volume previously tested in the setting of radiation-induced lung fibrosis were evaluated by two raters. These measurements were lung height, aortosternal distance, and oblique fissure retraction distance. Fibrosis extent on CT was scored by two observers. Correlation coefficients and multivariable regression analyses were performed to assess the relationship between CT measurements and percentage of predicted FVC (hereafter referred to as "percentage FVC") and TLC. Interobserver agreement for CT markers was evaluated on the basis of the intraclass correlation coefficient. RESULTS. There was a strong correlation between CT-derived automated lung volume and TLC (rP = 0.92; p < 0.0005). There was excellent interobserver agreement for all manual CT measurements (intraclass correlation coefficient, 0.82-0.96). There were significant correlations between manual CT measurements and percentage FVC. Lung height had the strongest relationship with percentage FVC (rP = 0.44; p < 0.0005). In multivariable analysis, the CT measurements were independent determinants of lung volumes, after adjustment for fibrosis and emphysema (R2 = 0.48; p < 0.0005 and p < 0.003, respectively). Lung height had the most significant impact on the fit against lung volumes. CONCLUSION. Automated and manual CT measurements of lung volume are significantly related to PFT-derived parameters of lung volume, independent of fibrosis and emphysema.

Dosimetry and Comparison between Different CT Protocols (Low Dose, Ultralow Dose, and Conventional CT) for Lung Nodules' Detection in a Phantom.

BACKGROUND: The effects of dose reduction in lung nodule detection need better understanding. PURPOSE: To compare the detection rate of simulated lung nodules in a chest phantom using different computed tomography protocols, low dose (LD), ultralow dose (ULD), and conventional (CCT), and to quantify their respective amount of radiation. MATERIALS AND METHODS: A chest phantom containing 93 simulated lung nodules was scanned using five different protocols: ULD (80 kVp/30 mA), LD A (120 kVp/20 mA), LD B (100 kVp/30 mA), LD C (120 kVp/30 mA), and CCT (120 kVp/automatic mA). Four chest radiologists analyzed a selected image from each protocol and registered in diagrams the nodules they detected. Kruskal-Wallis and McNemar's tests were performed to determine the difference in nodule detection. Equivalent doses were estimated by placing thermoluminescent dosimeters on the surface and inside the phantom. RESULTS: There was no significant difference in lung nodules' detection when comparing ULD and LD protocols (p=0.208 to p=1.000), but there was a significant difference when comparing each one of those against CCT (p < 0.001). The detection rate of nodules with CT attenuation values lower than -600 HU was also different when comparing all protocols against CCT (p < 0.001 to p=0.007). There was at least moderate agreement between observers in all protocols (κ-value >0.41). Equivalent dose values ranged from 0.5 to 9 mSv. CONCLUSION: There is no significant difference in simulated lung nodules' detection when comparing ULD and LD protocols, but both differ from CCT, especially when considering lower-attenuating nodules.

Angioinvasive pulmonary aspergillosis after allogeneic bone marrow transplantation: clinical and high-resolution computed tomography findings in 12 cases.

The aim of this study was to present the clinical and high-resolution CT scan findings of angioinvasive pulmonary aspergillosis (APA) in 12 patients who underwent allogeneic bone marrow transplantation (BMT). The CT scans were reviewed by three chest radiologists who assessed the pattern and distribution of findings by consent. There were 7 (58%) female and 5 (42%) male patients, with aging between 5 and 50 years (average of 26 years). All patients were submitted to BMT for the treatment of hematological conditions. The diagnosis of APA was defined between 5 and 373 days after BMT, with average of 111 days. Three cases (25%) were diagnosed in the neutropenic phase after the BMT, five (42%) in the early phase and four patients in the late phase post-BMT. Regarding high-resolution CT (HRCT) scan findings, nodules were found in 75% of the cases (9/12), most of the cases with more than 10 lesions (7/9) and of centrilobular localization (6/9). Consolidations were identified in seven patients (58%), being single in six, and commonly presenting ill defined borders (n=3) and subsegmental localization (n=5). Ground glass attenuation was found in six patients (50%). The halo sign was observed in nine cases (75%). Cavitations were seen in two air-space consolidations and one large nodule (2.5 cm). Patients submitted to BMT presenting respiratory symptoms and nodules or consolidations with halo sign at HRCT scan need to have the diagnosis of angioinvasive pulmonary aspergillosis included in all the post BMT phases.

Varicella pneumonia in immunocompetent adults: report of two cases, with emphasis on high-resolution computed tomography findings.

We report two cases of varicella pneumonia in immunocompetent patients, with emphasis on high-resolution computer tomography manifestations. The predominant findings consisted of multiple bilateral nodules, ranging from 1-10 mm in diameter, with or without a surrounding halo of ground-glass attenuation. Other findings include ground-glass opacities, focal areas of consolidation and small pleural effusions.

Disseminated tuberculosis in a pregnant woman presenting with numerous brain tuberculomas: case report.

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis, which has the pulmonary form as the most common presentation. Dissemination of the disease is common in immunocompromised patients, but immunodeficiency related to pregnancy severe enough to cause dissemination of the Mycobacteria is exceedingly rare. When dissemination occurs, any organ may be affected and in central nervous system, the infection presents as meningitis and single brain parenchyma tuberculomas. We report the case of a 17 year-old woman at the 34th week of pregnancy with respiratory and high intracranial pressure symptoms. On the day before admission she had a sudden onset of paraparesis and urinary retention and ten hours after the delivery she presented with paraplegia. The chest X-ray and CT scan were compatible with miliary tuberculosis. The cranial CT scan revealed numerous rounded hypodense lesions located at cerebral and cerebellar hemispheres, which presented ring-like enhancement after contrast injection. The patient underwent a craniotomy with biopsy of the lesions confirming the diagnosis of brain tuberculomas. The three-drug regimen was started and the cranial CT scan performed a year after diagnosis showed no brain lesions. We emphasize the aggressive dissemination of the disease in this case associated with pregnancy and the importance of early diagnosis and institution of therapy resulting in regression of the lesions.

Angioinvasive pulmonary aspergillosis after allogeneic bone marrow transplantation: clinical and high-resolution computed tomography findings in 12 cases

The aim of this study was to present the clinical and high-resolution CT scan findings of angioinvasive pulmonary aspergillosis (APA) in 12 patients who underwent allogeneic bone marrow transplantation (BMT). The CT scans were reviewed by three chest radiologists who assessed the pattern and distribution of findings by consent. There were 7 (58 percent) female and 5 (42 percent) male patients, with aging between 5 and 50 years (average of 26 years). All patients were submitted to BMT for the treatment of hematological conditions. The diagnosis of APA was defined between 5 and 373 days after BMT, with average of 111 days. Three cases (25 percent) were diagnosed in the neutropenic phase after the BMT, five (42 percent) in the early phase and four patients in the late phase post-BMT. Regarding high-resolution CT (HRCT) scan findings, nodules were found in 75 percent of the cases (9/12), most of the cases with more than 10 lesions (7/9) and of centrilobular localization (6/9). Consolidations were identified in seven patients (58 percent), being single in six, and commonly presenting ill defined borders (n=3) and subsegmental localization (n=5). Ground glass attenuation was found in six patients (50 percent). The halo sign was observed in nine cases (75 percent). Cavitations were seen in two air-space consolidations and one large nodule (2.5 cm). Patients submitted to BMT presenting respiratory symptoms and nodules or consolidations with halo sign at HRCT scan need to have the diagnosis of angioinvasive pulmonary aspergillosis included in all the post BMT phases.

Varicella pneumonia in immunocompetent adults: report of two cases, with emphasis on high-resolution computed tomography findings

We report two cases of varicella pneumonia in immunocompetent patients, with emphasis on high-resolution computer tomography manifestations. The predominant findings consisted of multiple bilateral nodules, ranging from 1-10 mm in diameter, with or without a surrounding halo of ground-glass attenuation. Other findings include ground-glass opacities, focal areas of consolidation and small pleural effusions.

Disseminated tuberculosis in a pregnant woman presenting with numerous brain tuberculomas: case report

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis, which has the pulmonary form as the most common presentation. Dissemination of the disease is common in immunocompromised patients, but immunodeficiency related to pregnancy severe enough to cause dissemination of the Mycobacteria is exceedingly rare. When dissemination occurs, any organ may be affected and in central nervous system, the infection presents as meningitis and single brain parenchyma tuberculomas. We report the case of a 17 year-old woman at the 34th week of pregnancy with respiratory and high intracranial pressure symptoms. On the day before admission she had a sudden onset of paraparesis and urinary retention and ten hours after the delivery she presented with paraplegia . The chest X-ray and CT scan were compatible with miliary tuberculosis. The cranial CT scan revealed numerous rounded hypodense lesions located at cerebral and cerebellar hemispheres, which presented ring-like enhancement after contrast injection. The patient underwent a craniotomy with biopsy of the lesions confirming the diagnosis of brain tuberculomas. The three-drug regimen was started and the cranial CT scan performed a year after diagnosis showed no brain lesions. We emphasize the aggressive dissemination of the disease in this case associated with pregnancy and the importance of early diagnosis and institution of therapy resulting in regression of the lesions