Thorax CT Dose Reduction Based on Patient Features: Effect of Patient Characteristics on Image Quality and Effective Dose.

Computed tomography (CT) radiation dose reduction is vital without compromising image quality. The aim was to determine the effects of patient characteristics on the received radiation dose and image quality in chest CT examinations and to be able to predict dose and image quality prior to scanning. Consecutive 230 patients underwent routine chest CT examinations were included. CT examination and patients input parameters were recorded for each patient. The effect of patients' demographics/anthropometrics on received dose and image quality was investigated by linear regression analysis. All parameters were evaluated using an artificial neural network (ANN). Of all parameters, patient demographics/anthropometrics were found to be 98% effective in calculating dose reduction. Using ANN on 60 new patients was more than 90% accurate for output parameters and 91% for image quality. Patient characteristics have a significant impact on radiation dose and image quality. Dose and image quality can be determined before CT. This will allow setting the most appropriate scanning parameters before the CT scan.

Prognostic values of ADCmean and SUVmax of the primary tumour in cervical cancer patients treated with definitive chemoradiotherapy.

We analysed the correlation of 18F-fluorodeoxyglucose uptake into primary tumours using the maximum standardised uptake value (SUVmax) and the mean apparent diffusion coefficient (ADCmean) values in magnetic resonance imaging (MRI) with the clinical and pathological factors in patients with cervical cancer who were treated with concurrent chemoradiotherapy. The patients were stratified according to the primary tumour pre-treatment ADCmean and SUVmax cut-off values. There were significant correlations between the SUVmax of the primary tumour and tumour size, and the treatment response. The correlation between the ADCmean and FIGO stage, tumour size, and the lymph node metastasis was significant. The SUVmax was significantly and inversely correlated with the ADCmean for cervical cancer (r = -0.44, p <.001). In the multivariate analysis, the primary tumour ADCmean, treatment response and the lymph node metastasis emerged as significant independent predictors of both OS and DFS, and of the primary tumour SUVmax for DFS. Tumour size has a borderline significance for OS. High SUVmax and low ADCmean of the primary tumour are important predictive factors for identifying high-risk patients with cervical cancer who are treated with definitive chemoradiotherapy. These results point to a future role for the diffusion-weighted MRI and for 18F-fluorodeoxyglucose positron emission tomography, not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy for individual patients. Impact statement What is already known on this subject? A negative correlation between primary tumour SUVmax derived from positron emission tomography (PET/CT) and ADCmin derived from diffusion weighted magnetic resonance imaging (DW-MRI) in various cancer types and cervical cancer has been demonstrated. However, the prognostic value of primary tumour SUVmax and ADCmean in cervical cancer patients treated with definitive chemoradiotherapy is not well studied yet. What the results of this study add? The patients with high-risk features (larger tumours, extensive stage, lymph node metastasis) had higher primary tumour SUVmax and lower ADCmean values. Primary tumour ADCmean and lymph node metastasis emerged as significant independent predictors of both overall and disease-free survival. This study demonstrated that the functional biomarkers delivered from PET-CT and DW-MRI are important in predicting the treatment outcomes in the squamous cell carcinoma of cervix treated with definitive chemoradiotherapy, where clinical and radiological findings are very important, since these patients are not staged surgically. What are the implications of these findings for clinical practice and/or further research? Based on these findings, there may be a future role of DW-MRI and FDG/PET-CT not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy (ChRT) for individual patients.

Utility of Diffusion Weighted Magnetic Resonance Imaging with Multiple B Values in Evaluation of Pancreatic Malignant and Benign Lesions and Pancreatitis.

OBJECTIVE: To determine the feasibility of diffusion-weighted imaging in evaluation of pancreatic lesions and in differentiation of benign from malignant lesions. STUDY DESIGN: Descriptive study. PLACE AND DURATION OF STUDY: Baskent University Adana Teaching and Research Center, Adana, Turkey, between September 2013 and May 2015. METHODOLOGY: Forty-three lesions [pancreas adenocarcinoma (n=25)], pancreatitis (n=10), benign lesion (n=8)] were utilized with diffusion-weighted magnetic resonance imaging with multiple b-values. Different ADC maps of diffusion weighted images by using b-values were acquired. RESULTS: The median ADC at all b values for malignant lesions was significantly different from that for benign lesions (p<0.001). When ADCs at all b values were compared between benign lesions/normal parenchyma and malignant lesions/normal parenchyma, there was a significant statistical difference in all b values between benign and malignant lesions except at b 50 and b 200 (p<0.05). The lesion/normal parenchyma ADC ratio for b 600 value (AUC=0.804) was more effective than the lesion ADC for b 600 value (AUC=0.766) in differentiation of benign and malignant lesions. The specificity and sensitivity of the lesion/normal parenchyma ADC ratio were higher than those of ADC values of lesions. When the ADC was compared between benign lesions and pancreatitis, a significant difference was found at all b values (p<0.001). There was not a statistically significant difference between the ADC for pancreatitis and that for malignant lesions at any b value combinations (p>0.05). CONCLUSION: Diffusion-weighted magnetic resonance images can be helpful in differentiation of pancreatic carcinoma and benign lesions. Lesion ADC / normal parenchyma ADC ratios are more important than lesion ADC values in assessment of pancreatic lesions.

Internal comparison standard for abdominal diffusion-weighted imaging.

Background Standards for abdominal diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) measurements, and analysis are required for reproducibility. Purpose To identify optimal internal comparison standards for DWI to normalize the measured ADC for increased accuracy of differentiating malignant and benign abdominal lesions. Material and Methods We retrospectively studied 97 lesions (89 patients; age, 57 ± 13 years) with histopathologically confirmed abdominal disease. Seven normal body parts/contents (normal parenchyma, spleen, kidney, gallbladder bile, paraspinal muscle, spinal cord, and cerebrospinal fluid [CSF]) were assessed as internal references for possible use as comparison standards. Three observers performed ADC measurements. Statistical analyses included interclass correlation coefficients (ICCs), Mann-Whitney and Kruskal-Wallis tests, and coefficient of variation (CV). ROC analyses were performed to assess diagnostic accuracy of lesion ADC and normalized ADC for differentiating lesions. Pathology results were the reference standard. Results Mean and normalized ADCs were significantly lower for malignant lesions than for benign lesions ( P < 0.001). ICC was excellent for all internal references. Gallbladder had the lowest CV. Receiver operating characteristic (ROC) analyses showed that normalized ADCs obtained using normal parenchyma were better than lesion ADCs for differentiating malignant and benign abdominal lesions (area under the curve [AUC], 0.808 and 0.756, respectively). The normalized ADCs obtained using CSF shows higher accuracy than lesion ADCs (0.80 and 0.76, respectively) for differentiating between malignant and benign abdominal lesions. Conclusion The normal parenchyma from a lesion-detected organ can be used as an internal comparison standard for DWI. CSF can be used as a generalizable in plane reference standard.

Predicting tumor recurrence in patients with cervical carcinoma treated with definitive chemoradiotherapy: value of quantitative histogram analysis on diffusion-weighted MR images.

Background Further research is required for evaluating the use of ADC histogram analysis in more advanced stages of cervical cancer treated with definitive chemoradiotherapy (CRT). Purpose To investigate the utility of apparent diffusion coefficient (ADC) histogram derived from diffusion-weighted magnetic resonance images in cervical cancer patients treated with definitive CRT. Material and Methods The clinical and radiological data of 50 patients with histologically proven cervical squamous cell carcinoma treated with definitive CRT were retrospectively analyzed. The impact of clinicopathological factors and ADC histogram parameters on prognostic factors and treatment outcomes was assessed. Results The mean and median ADC values for the cohort were 1.043 ± 0.135 × 10-3 mm2/s and 1.018 × 10-3 mm2/s (range, 0.787-1.443 × 10-3 mm2/s). The mean ADC was significantly lower for patients with advanced stage (≥IIB) or lymph node metastasis compared with patients with stage

Utility of Diffusion-Weighted MRI to Detect Changes in Liver Diffusion in Benign and Malignant Distal Bile Duct Obstruction: The Influence of Choice of b-Values.

PURPOSE: The study sought to evaluate the potential of diffusion-weighted magnetic resonance imaging to detect changes in liver diffusion in benign and malignant distal bile duct obstruction and to investigate the effect of the choice of b-values on apparent diffusion coefficient (ADC). METHODS: Diffusion-weighted imaging was acquired with b-values of 200, 600, 800, and 1000 s/mm2. ADC values were obtained in 4 segments of the liver. The mean ADC values of 16 patients with malignant distal bile duct obstruction, 14 patients with benign distal bile duct obstruction, and a control group of 16 healthy patients were compared. RESULTS: Mean ADC values for 4 liver segments were lower in the malignant obstruction group than in the benign obstruction and control groups using b = 200 s/mm2 (P < .05). Mean ADC values of the left lobe medial and lateral segments were lower in the malignant obstruction group than in the benign obstructive and control groups using b = 600 s/mm2 (P < .05). Mean ADC values of the right lobe posterior segment were lower in the malignant and benign obstruction groups than in the control group using b = 1000 s/mm2 (P < .05). Using b = 800 s/mm2, ADC values of all 4 liver segments in each group were not significantly different (P > .05). There were no correlations between the ADC values of liver segments and liver function tests. CONCLUSION: Measurement of ADC shows good potential for detecting changes in liver diffusion in patients with distal bile duct obstruction. Calculated ADC values were affected by the choice of b-values.

Effect of Hereditary Hemochromatosis Gene H63D and C282Y Mutations on Iron Overload in Sickle Cell Disease Patients.

OBJECTIVE: Hemochromatosis is an autosomal recessive disease that is one of the most important reasons for iron overload. Sickle cell disease is a hemoglobinopathy that occurs as a result of a homozygous mutation in the hemoglobin gene. Erythrocyte transfusion is frequently used in the treatment of this disease. Iron overload as a result of transfusion is important in the mortality and morbidity of sickle cell anemia patients as well as in other hemoglobinopathies. In this study, the effect of hemochromatosis gene (HFE) p.H63D and p.C282Y mutations on transfusion-related cardiac and liver iron overload in sickle cell disease patients who carry homozygous hemoglobin S mutation has been investigated. MATERIALS AND METHODS: This is a prospective single-center cross-sectional study in patients with homozygous hemoglobin S mutation between the years 2008 and 2013. The patients were divided into two groups. The first group (group A, n=31) was receiving chelation therapy and the second group (group B, n=13) was not. Direct and indirect iron loads were analyzed by magnetic resonance imaging and biochemically, respectively. HFE gene mutations were analyzed by polymerase chain reaction-restriction fragment length polymorphism method. Statistical analyses were performed by independent samples t-test. RESULTS: p.H63D mutation was detected in 10 (32.3%) patients in group A and in only 1 patient (7.7%) in group B. When the 2 groups were compared for iron overload, iron deposition in the liver was significantly higher in group B (p=0.046). In addition, in group A, iron deposition was significantly higher in HFE mutation carriers compared to patients without the mutation (p=0.05). CONCLUSION: Results of this study showed that HFE gene mutations are important in iron deposition in the liver in patients with sickle cell disease.

A rarely seen diffuse parenchymal lung disease: diffuse pulmonary meningotheliomatosis.

Pulmonary meningothelial-like nodules (MLNs) are usually detected incidentally during pathologic evaluation of resected pulmonary parenchymal specimens and autopsies. These nodules are generally asymptomatic and most often single. Diffuse pulmonary involvement by MLNs is less frequently described. MLNs are benign lesions and have been associated with neoplastic and non-neoplastic pulmonary conditions and occasionally with extrapulmonary diseases. We report a case of a female patient presenting with multiple and bilateral pulmonary nodules diagnosed with "diffuse pulmonary meningotheliomatosis" by video-assisted thoracoscopic surgery (VATS). Diffuse pulmonary meningotheliomatosis should be included in the differential diagnosis of diffuse bilateral lung nodules in the radiologic studies.

Diffusion-weighted MRI and optimal b-value for characterization of liver lesions.

BACKGROUND: Diffusion-weighted imaging (DWI) is commonly used to distinguish between benign and malignant liver lesions. However, different b-values are recommended. PURPOSE: To determine the most suitable b-value in DWI for differentiation of benign and malignant liver lesions. MATERIAL AND METHODS: A total of 124 lesions in 89 consecutive patients (43 men, 46 women; age, mean ± standard deviation, 58 ± 14 years) with a pathological or radiological diagnosis of malignant or benign focal liver lesions after magnetic resonance imaging (MRI) were included in this study. Routine abdominal MRI and DWI were performed using seven b-values (0, 50, 200, 400, 600, 800, 1000 s/mm(2)). Lesions were analyzed for benignity/malignity using apparent diffusion coefficient (ADC) values with 10 b-value combinations and by measuring the lesion/normal parenchyma ADC ratio. RESULTS: Mean ADC values were significantly different between malignant and benign lesions for all b-value combinations (P=0.000). The best b-value combination was 0 and 800 (Az=0.935). Using lower b-values such as 0 and 50 together with higher b-values ≥ 600 s/mm(2) was beneficial (Az=0.928 and 0.927). Mean ADC values were approximately 13% (1-15%) higher in total when b=0 and b=50 s/mm(2) were included in multiple b-value combinations. CONCLUSION: In DWI, we recommend the use of b-values of 0 and 800 s/mm(2) as two b-values, or b=0, 50, 600, 800, and 1000 s/mm(2) as multiple b-values for distinguishing between benign and malignant liver lesions. Mean ADC value is 13% higher in total by additional use of b=0 and b=50 s/mm(2) in multiple b-value combinations.

Optimal b value in diffusion-weighted imaging for differentiation of abdominal lesions.

PURPOSE: To explore the optimal b value in diffusion-weighted imaging (DWI) for differentiation of benign and malignant abdominal lesions. MATERIALS AND METHODS: A total of 108 consecutive patients (age 60 ± 12.5 years) with 127 pathologically confirmed diagnoses of abdominal lesions were included. Single-shot echoplanar imaging (SH-EPI) DWI (1.5T) with seven b values and eight apparent diffusion coefficient (ADC) maps were obtained. The lesions were analyzed visually on DWI and ADC maps for benignity/malignity using a 5-point scale and by measuring the ADC values and ADC lesion/normal parenchyma ADC ratio. ROC analysis was used to evaluate the diagnostic accuracy of ADC for differentiating between benign and malignant lesions. Pathology results were the reference standard. RESULTS: Differentiation between malignant and benign lesions using visual scoring was successful at b values of 600 or higher (sensitivities, specificities, and accuracies were 100/93.8/92.5, 84.7/82.6/80.4, and 94.4/89.7/88.1, respectively, for b600, 800, and 1000). The mean ADC values of malignant lesions were significantly lower than those of benign lesions for all b-value combinations except b0 and 50 s/mm(2) (P = 0.032 for b0 and 50 s/mm(2) , P = 0.000 for other b values). The best b-value combination was 0 and 600 s/mm(2) and multiple b2. The lesion/normal parenchymal ADC ratio for b600, b1000, and multiple b2 better distinguished between benign and malignant lesions. CONCLUSION: In DWI, the optimal b value is 600 s/mm(2) ; multiple b values of 600 s/mm(2) and higher are recommended to differentiate between benign and malignant abdominal lesions. The lesion ADC/normal parenchyma ADC ratio is more accurate than using lesion ADC only.

Radiation recall pneumonitis caused by erlotinib after palliative definitive radiotherapy.

BACKGROUND: Radiation recall pneumonitis (RRP) occurs in a previously irradiated field and is triggered by certain cytotoxic drugs, principally chemotherapeutic agents such as erlotinib. Erlotinib is a reversible epidermal growth factor receptor tyrosine kinase inhibitor (TKI) and is an effective second-line treatment for patients with advanced-stage non-squamous-cell lung cancer. Previously, only 2 cases of radiation recall after erlotinib treatment have been reported. Here, we report a case of RRP caused by treatment with erlotinib 4 months after palliative definitive hypofractionated radiation therapy (RT). PATIENT AND METHODS: A 58-year-old male patient with non-small cell lung cancer (adenocarcinoma) was treated with polychemotherapy, palliative RT (30 Gy in 10 fractions), and erlotinib thereafter. RESULTS: Dosimetric analysis obtained from a 3-dimensional conformal RT planning system revealed that the volume of lung receiving at least 20 Gy (V20) was 21.2% and the mean lung dose was 12.7 Gy. These data indicate that systemic administration of a TKI, even after palliative RT, may lead to unexpected toxicity when the radiation field encompasses visceral organs. CONCLUSION: We conclude that the use of a TKI after RT may trigger radiation pneumonitis. Although evidence is limited, we advise clinicians to be cautious of RRP after erlotinib treatment.

Imaging and clinical findings of a gossypiboma migrated into the stomach.

In the presented case, the radiologic, endoscopic and surgical findings of a gossypiboma that migrated into the stomach are presented. A 63-year-old woman presented with epigastric pain, and her clinical and laboratory findings were compatible with pancreatitis. Upper gastrointestinal endoscopy revealed a foreign body at the greater curvature of the stomach. Computed tomography and magnetic resonance imaging showed a mass consistent with a gossypiboma that had migrated into the stomach transmurally. This is a first case of a gossypiboma diagnosed endoscopically.

Evaluation of malignant and benign renal lesions using diffusion-weighted MRI with multiple b values.

BACKGROUND: Limited data are available regarding the use of diffusion-weighted (DW) magnetic resonance imaging (MRI) with multiple b values for characterization of renal lesions. PURPOSE: To demonstrate and compare the diagnostic performance of DW-MRI with multiple b values for renal lesion characterization. MATERIAL AND METHODS: Sixty-three lesions (36 malignant, 27 benign) in 60 consecutive patients (48 men, 12 women; age 60 ± 12.5 years) with solid/cystic renal lesion diagnosed after MRI were included prospectively. Single-shot echo-planar DW abdominal MRI (1.5T) was obtained using seven b values with eight apparent diffusion coefficient (ADC) maps. Contrast-to-noise ratios (CNRs), signal intensities, lesion ADCs, and lesion/normal parenchyma ADC ratios were analyzed. Receiver-operating characteristic analysis was performed. RESULTS: The mean signal intensities of malignant lesions (at b0, 50, and 200s/mm(2)) were significantly lower than those of benign lesions (P < 0.05). The mean ADC values at all b value combinations of malignant lesions were significantly lower than those of benign lesions (P < 0.000), excluding the ADC value at b50 s/mm(2). ADC with all b values could better distinguish between benign and malignant lesions. A 1.35 × 10(-3) mm(2)/s threshold ADC value permitted this distinction with 85.2% sensitivity and 65.6% specificity. The lesion/normal parenchyma ADC ratio was more effective than the lesion ADC. CONCLUSION: In addition to the ADC value, the signal intensity curve on DW images using multiple b values could be helpful for differentiation of malignant and benign renal lesions.

Optimization of b value in diffusion-weighted MRI for characterization of benign and malignant gynecological lesions.

PURPOSE: To explore the optimal b value in diffusion-weighted (DW)-MRI for differentiation of benign and malignant gynecological lesions. MATERIALS AND METHODS: Consecutive 58 patients (66 lesions) with pathologically confirmed diagnosis of gynecological disease were included in the study. Routine pelvic MRI sequences were used for defining the lesions and reviewed independently for benignity/ malignity. Single-shot echoplanar imaging (SH-EPI) DW-MRI with eight b values and nine apparent diffusion coefficient (ADC) maps were obtained. The lesions were analyzed qualitatively on DW-MRI for benignity/malignity on a five-point-scale and quantitatively by measurement of apparent diffusion coefficient (ADC) values. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of ADC values for differentiating between benign and malignant lesions. Pathology results were the reference standard. RESULTS: Differentiation between benign and malignant gynecological lesions using visual scoring was found to be successful with b values of 600, 800, or 1000 s/mm(2) . The mean ADC values of malignant lesions were significantly lower than those of benign lesions for all b value (P < 0.005). The ADCs with b = 0 and 600, 0 and 1000 s/mm(2) , 0, 600, 800 and 1000 s/mm(2) , and all b values were more effective for distinguishing malignant from benign gynecological lesions (Az = 0.851, 0.847, 0.848, 0.849, respectively). Using ADC with b = 0, 600, 800, and 1000 s/mm(2) , a threshold value of 1.20 × 10(-3) mm(2) /s permitted this distinction with a sensitivity of 83%, a specificity of 81%. CONCLUSION: DW-MRI is an important method, and the optimal b values are between 600 and 1000 s/mm(2) for differentiation between benign and malignant gynecological lesions.

Morphometric MRI evaluation of corpus callosum and ventricles in normal adults.

OBJECTIVES: The aim of this study was to determine the normal values of subregions of corpus callosum and ventricles in healthy adult people in our population using magnetic resonance imaging (MRI) and to establish gender differences. METHODS: The MRI of 52 healthy individuals (29 females and 23 males) aged 20-50 years was obtained. The measurements were performed from MRI on a workstation. The midsagittal images were used for measurements of the subregions of corpus callosum and axial images were for lateral and third ventricles. RESULTS: The mean values of the widths of genu, body, splenium, and height of the corpus callosum were 13·28±2·10, 7·64±1·07, 12·52±1·35, and 25·47±2·20 mm, respectively in females; whereas, the same measurements were 13·23±2·41, 6·89±2·12, 11·90±1·94, and 25·03±3·38 mm, respectively in males. Moreover, the mean value for the longitudinal dimension of the brain was 150·12±5·04 mm, while that for the corpus callosum was 71·27±3·70 mm in females. Additionally, the mean frontal horn width of the lateral ventricle and the transverse inner diameter of the skull were 34·06±3·05 and 130·76±6·71 mm in females and 34·03±2·78 and 129·96±10·61 mm in males, respectively. Due to these measurements, the values of Evans index which is reflecting the lateral ventricle enlargement were estimated to be 0·25±1·90 and 0·25±1·14 in females and males, respectively. According to our last measurement result, the mean values for the third ventricle width were 3·79±0·85 and 4·12±0·94 mm in females and males, respectively. These findings show that there are differences between the averages of some indices of corpus callosum of our population and the other populations.

Multidetector computed tomography diagnosis of ileal and antropyloric gallstone ileus.

Gallstone-induced ileus is a rare complication of cholelithiasis, and gastric outlet obstruction is even rarer. We describe the multidetector computed tomographic diagnosis of small bowel obstruction resulting from a gallstone impacted in the distal ileum and of gastric outlet obstruction from a gallstone impacted in the pyloric antrum (Bouveret syndrome).

Evaluation of portal venous velocity with Doppler ultrasound in patients with nonalcoholic fatty liver disease.

PURPOSE: We examined the relationship between portal venous velocity and hepatic-abdominal fat in patients with nonalcoholic fatty liver disease (NAFLD), using spectral Doppler ultrasonography (US) and magnetic resonance imaging (MRI). MATERIALS AND METHODS: In this prospective study, 35 patients with NAFLD and 29 normal healthy adults (control group) underwent portal Doppler US. The severity of hepatic steatosis in patients with NAFLD was assessed by MRI through chemical shift imaging, using a modification of the Dixon method. Abdominal (intra-abdominal and subcutaneous) fat was measured by MRI. RESULTS: The difference in portal venous velocity between the patients with NAFLD and the control group was significant (p < 0.0001). There was no correlation between the degree of abdominal or hepatic fat and portal venous velocity (p > 0.05). There were strong correlations between the hepatic fat fraction and subcutaneous adiposity (p < 0.0001), intraperitoneal fat accumulation (p = 0.017), and retroperitoneal fat accumulation (p < 0.0001). CONCLUSION: Our findings suggest that patients with NAFLD have lower portal venous velocities than normal healthy subjects.

Chest radiography and CT findings in patients with the 2009 pandemic (H1N1) influenza.

PURPOSE: To present chest radiography and thoracic computed tomography (CT) findings for patients with pandemic influenza A (H1N1) from November-December 2009 and to explore any differences compared to previously reported imaging findings. MATERIALS AND METHODS: Fifty-two hospitalized patients with pandemic influenza (H1N1) were included in the study. All of the patients underwent chest radiography, and 28 patients were also evaluated by thoracic CT. Group 1 comprised 24 (46%) patients with no identified risk factors for H1N1 influenza infection. Group 2 comprised the remaining 28 (54%) patients with identified risk factors. The distribution of lung involvement, consolidation, ground-glass opacity (GGO), lymph nodes, and pleural effusion were evaluated. RESULTS: Abnormal findings were observed in 85% of the patients. Bilateral lung involvement was present in 80% of the patients. The most common finding was a mixture of GGO and air-space consolidation. Lower zone predominance occurred in 89% of group 1 and 85% of group 2 patients. The involvement was observed most frequently in the peripheral and central perihilar areas of the lung in 80% of the patients. The extent of disease was greater in group 2 patients with the involvement of three or more lung zones in 62% of the patients. CONCLUSION: The most common imaging finding for lung involvement was a mixture of air-space consolidation and GGO with a patchy pattern and lower/middle zone predominance. Pulmonary involvement of the disease was more extensive than that described in previous reports.