Relation of impulse oscillometry and spirometry with quantitative thorax computed tomography after COVID-19 pneumonia.

OBJECTIVE: This study aimed to investigate if there is any correlation between the quantitative computed tomography and the impulse oscillometry or spirometry results of post-COVID-19 patients. METHODS: The study comprised 47 post-COVID-19 patients who had spirometry, impulse oscillometry, and high-resolution computed tomography examinations at the same time. The study group consisted of 33 patients with quantitative computed tomography involvement, while the control group included 14 patients who did not have CT findings. The quantitative computed tomography technology was used to calculate percentages of density range volumes. The relationship between percentages of density range volumes for different quantitative computed tomography density ranges and impulse oscillometry-spirometry findings was statistically analyzed. RESULTS: In quantitative computed tomography, the percentage of relatively high-density lung parenchyma, including fibrotic areas, was 1.76±0.43 and 5.65±3.73 in the control and study groups, respectively. The percentages of primarily ground-glass parenchyma areas were found to be 7.60±2.86 and 29.25±16.50 in the control and study groups, respectively. In the correlation analysis, the forced vital capacity% predicted in the study group was correlated with DRV%[(-750)-(-500)] (volume of the lung parenchyma that has density between (-750)-(-500) Hounsfield units), but no correlation with DRV%[(-500)-0] was detected. Also, reactance area and resonant frequency were correlated with DRV%[(-750)-(-500)], while X5 was correlated with both DRV%[(-500)-0] and DRV%[(-750)-(-500)] density. Modified Medical Research Council score was correlated with predicted percentages of forced vital capacity and X5. CONCLUSION: After COVID-19, forced vital capacity, reactance area, resonant frequency, and X5 correlated with the percentages of density range volumes of ground-glass opacity areas in the quantitative computed tomography. X5 was the only parameter correlated with density ranges consistent with both ground-glass opacity and fibrosis. Furthermore, the percentages of forced vital capacity and X5 were shown to be associated with the perception of dyspnea.

Can Ultrasonographic Measurement of Bone Cortical Thickness Predict Osteoporosis?

RATIONALE AND OBJECTIVES: In this study, we aimed to describe a more accessible and safe diagnostic tool for osteoporosis or osteopenia diagnosis. We utilized cortical thickness (CoT) measurement of various bones via ultrasonography and evaluated the method's accuracy relative to bone mineral density (BMD) results determined by dual-energy X-ray absorptiometry (DXA). MATERIALS AND METHODS: A total of 200 volunteers (all female) who agreed to participate in the study and had undergone BMD measurement (femoral or vertebral) were included in the study. Patients with normal BMD result (≥-1.0 T-score) were defined as controls. CoT measurements were made from three bones (radius, tibia, and second metatarsal) for each patient via ultrasonography. RESULTS: Radius CoT and tibial CoT measurements of both femoral and vertebral osteoporotic or osteopenic patients were significantly higher compared to controls. Second metatarsal CoT of femoral osteoporotic and osteopenic patients was also found to be significantly higher than the control group. We found tibia CoT and radius CoT to have high sensitivity and positive predictive value in identifying patients with abnormal femoral T-scores (<-1). In multivariable analyzes, radius CoT was found to be independently predictive in distinguishing patients with abnormal T-score (<-1) from controls in both the femur and vertebral BMD groups. CONCLUSION: Radius CoT and tibia CoT values appear to have value in predicting patients with abnormal T-scores measured via DXA. This method may be a very simple technique that can be used for early detection of osteoporosis and osteopenia, but its results need to be supported by more comprehensive studies.

Relation of impulse oscillometry and spirometry with quantitative thorax computed tomography after COVID-19 pneumonia

SUMMARY OBJECTIVE: This study aimed to investigate if there is any correlation between the quantitative computed tomography and the impulse oscillometry or spirometry results of post-COVID-19 patients. METHODS: The study comprised 47 post-COVID-19 patients who had spirometry, impulse oscillometry, and high-resolution computed tomography examinations at the same time. The study group consisted of 33 patients with quantitative computed tomography involvement, while the control group included 14 patients who did not have CT findings. The quantitative computed tomography technology was used to calculate percentages of density range volumes. The relationship between percentages of density range volumes for different quantitative computed tomography density ranges and impulse oscillometry-spirometry findings was statistically analyzed. RESULTS: In quantitative computed tomography, the percentage of relatively high-density lung parenchyma, including fibrotic areas, was 1.76±0.43 and 5.65±3.73 in the control and study groups, respectively. The percentages of primarily ground-glass parenchyma areas were found to be 7.60±2.86 and 29.25±16.50 in the control and study groups, respectively. In the correlation analysis, the forced vital capacity% predicted in the study group was correlated with DRV%[(-750)-(-500)] (volume of the lung parenchyma that has density between (-750)-(-500) Hounsfield units), but no correlation with DRV%[(-500)-0] was detected. Also, reactance area and resonant frequency were correlated with DRV%[(-750)-(-500)], while X5 was correlated with both DRV%[(-500)-0] and DRV%[(-750)-(-500)] density. Modified Medical Research Council score was correlated with predicted percentages of forced vital capacity and X5. CONCLUSION: After COVID-19, forced vital capacity, reactance area, resonant frequency, and X5 correlated with the percentages of density range volumes of ground-glass opacity areas in the quantitative computed tomography. X5 was the only parameter correlated with density ranges consistent with both ground-glass opacity and fibrosis. Furthermore, the percentages of forced vital capacity and X5 were shown to be associated with the perception of dyspnea.

FDG PET/CT Imaging Findings of Renal Infarction in a Patient With Gastric Adenocarcinoma.

ABSTRACT: We report the FDG PET/CT findings of renal infarction in a 75-year-old woman patient who received chemotherapy for gastric adenocarcinoma. The patient was referred to our hospital for the evaluation of her response to chemotherapy. PET/CT detected circumferential increased FDG uptake in the outer part of the left renal cortex. The remaining of the renal cortex was photopenic. Abdominal CT angiography showed no contrast enhancement within the renal parenchyma. There was no contrast enhancement in the lumen of the left renal artery. These findings were thought to be consistent with the left renal infarct due to the occlusion of the left renal artery.

Computed Tomography Findings in Progressive Massive Fibrosis: Analyses of 90 Cases.

PURPOSE: Radiological identification of lung masses in patients with pneumoconiosis is difficult. The aim of the study is to characterize Computed Tomography (CT) findings of Progressive Massive Fibrosis (PMF). METHODS: The data of pneumoconiosis patients, who were diagnosed with PMF between 2014-2019 in a tertiary hospital, were collected. Demographic data, work-related data, Pulmonary Function Test results and radiological imaging results were gathered. Separate evaluations were made for the right and left lungs, and the CT findings and measurement results were recorded. RESULTS: In 90% of our cases, PMF lesions were bilaterally located. Eighty-eight point five percent of the unilateral lesions were located in the upper lobe of the right lung. Enlarged lymph nodes were found in 83.3% and calcification was found in the lymph nodes in 63% of the cases. Band structures extending between the PMF lesion and the adjacent pleura were observed in 86% of the cases, and invagination in the lung parenchyma adjacent to the PMF was observed in 80% of the cases. CONCLUSION: In general, our findings were consistent with the radiologically defined PMF. In addition, pleural findings, which are not frequently studied in the literature except for asbestosis, were also described in the study. METHODS: The data of pneumoconiosis patients, who were diagnosed with PMF between 2014-2019 in a tertiary hospital, were collected. Demographic data, work-related data, PFT results and radiological imaging results were noted. Separate evaluations were made for the right and left lungs, and the CT findings and measurement results were recorded. RESULTS: In 90% of our cases, PMF lesions were bilaterally located. 88.8% of the unilateral lesions were located in the upper lobe of the right lung. Enlarged lymph nodes were found in 83.3% and calcification was found in the lymph nodes in 63% of the cases. Band structures extending between the PMF lesion and the adjacent pleura were observed in 86% of the cases, and invagination in the lung parenchyma adjacent to the PMF was observed in 80% of the cases. CONCLUSION: In general, our findings were consistent with the radiologically defined PMF. In addition, pleural findings, which are not frequently studied in the literature except asbestosis, were also described in the study.

Relationship between chest computed tomography findings and clinical conditions of coronavirus disease (COVID-19): A multicentre experience.

AIMS: This study aimed to investigate the clinical and chest computed tomography (CT) features associated with clinical parameters for coronavirus disease (COVID-19) in the capital of Turkey, Ankara. MATERIALS AND METHODS: Epidemiological, clinical features, laboratory findings and radiological characteristics of 1563 hospitalised patients with COVID-19 in Ankara were collected, reviewed and analysed in this study. The risk factors associated with disease severity were investigated. RESULTS: Non-severe (1214; 77.7%) and severe cases (349; 22.3%) were enrolled in the study. Compared with the non-severe group, the severe group were significantly older and had more comorbidities (ie, hypertension, diabetes mellitus, cardiovascular disease and chronic kidney disease). Smoking was more common in the severe group. Severe patients had higher respiratory rates and higher incidences of cough and dyspnoea compared with non-severe patients. Compared with the non-severe patients, the severe patients had increased C-reactive protein (CRP), procalcitonin, neutrophil to lymphocyte ratio (NLR) and CRP/albumin ratio and decreased albumin. The occurrence rates of consolidation, subpleural sparing, crazy-paving pattern, cavity, halo sign, reversed halo sign, air bronchogram, pleural thickening, micronodule, subpleural curvilinear line and multilobar and bilateral involvement in the CT finding of the severe patients were significantly higher than those of the non-severe patients. CONCLUSIONS: Many factors are related to the severity of COVID-19, which can help clinicians judge the severity of the patient and evaluate the prognosis. This cohort study revealed that male sex, age (≥55 years), patients with any comorbidities, especially those with cardiovascular disease, dyspnoea, increased CRP, D-dimer and NLR, and decreased lymphocyte count and CT findings of consolidation and multilobar involvement were predictors of severe COVID-19.

Comparison of the International Classification of High-resolution Computed Tomography for occupational and environmental respiratory diseases with the International Labor Organization International Classification of Radiographs of Pneumoconiosis.

The International Classification of High-resolution Computed Tomography for Occupational and Environmental Respiratory Diseases (ICOERD) has been developed for screening and diagnosis of occupational lung diseases. We evaluated the association of icoerd with the International Labor Organization (ILO) classification and respiratory functions in pneumoconiosis. Chest x-rays of patients with pneumoconiosis were classified with ilo and icoerd using hrct, irregular opacity, pleural pathology, and emphysema was detected in 78, 19, and 53 patients, and using chest x-rays in 47, 4, and 14 patients, respectively. There was a significant correlation between ILO categories and ICOERD grades. There was a negative correlation between ILO categories and FEV1% and FVC%, whereas, ICOERD grades were not correlated with FEV1% and FVC%. HRCT was superior to chest x-rays to detect pneumoconiosis in early stage, but not in evaluating pulmonary functions.

The Correlation Between Pre-treatment Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Parameters and Clinical Prognostic Factors in Pediatric Hodgkin Lymphoma.

OBJECTIVE: To compare standardized uptake values (SUV) derived from pre-treatment 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging and clinical prognostic factors in pediatric patients with Hodgkin lymphoma (HL). METHODS: Pre-treatment FDG PET/CT findings of 28 children with HL were evaluated in this retrospective study. Metabolic tumor volume (MTV), SUVmax normalized by weight (SUVweight), lean body mass (SUVlbm), body surface area (SUVbsa) and plasma glucose levels of tumors (SUVglucose) were calculated using pre-treatment FDG PET/CT scan images. These metabolic parameters were correlated with clinical factors [age, sex, number of lymph node groups, presence of splenic involvement, bulky mediastinal disease, Ann Arbor stage, serum white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), serum albumin and hemoglobin levels]. RESULTS: SUVbsa, SUVlbm, SUVweight, SUVglucose and MTV were higher in patients with stage III-IV disease, bulky tumor and ≥3 lymph node groups (p<0.05). SUVbsa and SUVglucose were higher in patients with splenic involvement (p<0.05). There was no significant correlation between these metabolic parameters and sex, ESR, levels of albumin and WBC (p>0.05). SUVbsa and SUVlbm were higher in patients with anemia (p<0.05). Additionally, significant increases were detected in SUVweight, MTV, and SUVglucose with increasing age (p=0.005, p=0.027, and p=0.009, respectively). SUVbsa and SUVlbm had no significant correlation with age (p>0.05). CONCLUSION: Metabolic parameters derived from pre-treatment FDG PET/CT may have an important role in predicting high-risk disease in patients with HL. Also, SUVbsa and SUVlbm may be better markers than SUVweight in the quantitative evaluation of FDG PET/CT scans in pediatric patients.

Occipital Hypometabolism on FDG PET/CT Scan in a Child with Hodgkin's Lymphoma.

It is known that Fluorodeoxyglucose (FDG) Positron Emission/Computed Tomography (PET/CT) images may be helpful for evaluation of brain function in newborns. Here we described the fluorine-18 [18-F] FDG PET/CT imaging findings of encephalomalacia due to perinatal asphyxia in a child with refractory Hodgkin's Lymphoma (HL) who underwent PET/CT scan to stage the primary disease. Prominent hypometabolism was incidentally detected in the occipital regions bilaterally apart from the FDG uptakes in the malign lymphatic infiltrations. This case highlights the potential coexistence of a malignancy and a functional brain disorder.

Correlation of Ki-67 proliferation index and 18-fluorodeoxyglucose uptake in colorectal incidental lesions detected by positron emission tomography-computed tomography.

BACKGROUND/AIM: To investigate whether focal high maximum standardized uptake value (SUVmax) determined by 18-fluorodeoxyglucose (FDG) positron emission tomography (PET)-computed tomography (CT) imaging is correlated with proliferation index in the colorectal region. MATERIALS AND METHODS: SUVmax values of 31 colorectal neoplasms that were incidentally detected during PET-CT examination were compared to dysplasia degree, histopathologic diagnosis, and immunohistochemical expression of the Ki-67 proliferation marker. RESULTS: Statistically significant correlations were found between SUVmax and Ki-67 proliferation index, dysplasia degree, and histopathologic diagnosis. Median SUVmax value was found to be significantly higher in high-risk lesions than low-risk lesions. CONCLUSION: The Ki-67 proliferation index is an indicator of SUVmax in colorectal tract. SUVmax values can predict malignancy and prognosis in this region. Colonoscopy and biopsy should always be performed whenever a focal high FDG uptake is determined incidentally in a patient.

18F-FDG PET/CT Imaging of Hodgkin Lymphoma in a Child with Common Variable Immunodeficiency.

Common variable immunodeficiency is characterized by low levels of serum immunoglobulins and antibodies, recurrent infections, and a predisposition to malignancy. Here, we present the 18F-FDG PET/CT findings of a 7-y-old boy with common variable immunodeficiency and Hodgkin lymphoma.

The potential value of volume-based quantitative PET parameters and increased bone marrow uptake for the prediction of survival in patients with malignant pleural mesothelioma.

PURPOSE: The aim of this study was to investigate the relationship between volume-based quantitative PET parameters and survival in patients with malignant pleural mesothelioma (MPM) and to evaluate the potential value of bone marrow (BM) uptake in predicting prognosis. MATERIALS AND METHODS: We retrospectively reviewed the data of 51 patients with MPM who underwent initial staging by fluorine-18-fluorodeoxyglucose (F-FDG) PET/computerized tomography (PET/CT). F-FDG-PET images were visually and quantitatively re-evaluated and maximum standardized uptake values (SUVmax), mean standardized uptake values (SUVmean), metabolic tumor volume (MTV), total lesion glycolysis of primary tumors, and pleural thickening were calculated. In addition, BM and liver uptakes were measured; also, the degree of BM uptake was scored visually. BM/liver ratio and visual BM uptake score were noted. The correlations between quantitative PET parameters, BM uptake, and overall survival were analyzed. RESULTS: F-FDG-PET scans upstaged 6 (11.8%) of 51 patients because of detection of previously unknown distant metastasis. On univariate analysis, advanced disease stage, high leukocyte count (≥10×10/ml), pleural thickening greater than 13 mm, SUVmax, SUVmean, MTV, total lesion glycolysis, BM/liver greater than 1.01, and visual score 1 and 2 were negative prognostic factors (P<0.05). In multivariate analysis, SUVmax greater than 8.6 [P=0.027, hazard ratio (HR): 2.961], MTV greater than 112 (P=0.001, HR: 4.861), and visual score 2 (P=0.035, HR: 3.827) were associated independently with a poor prognosis. CONCLUSION: The presence of distant metastasis is more predictive of survival than PET nodal status in MPM patients. PET/CT has the potential to provide prognostic information in MPM patients and there was a good correlation between overall survival and volume-based PET parameters. Determination of BM uptake may contribute toward the prediction of patient outcome with other quantitative PET parameters.

Use of FDG PET/CT in Patients with Pancoast Tumors: Does It Add Any Contribution to Patient Management?

PURPOSE: To evaluate any potential value of 2-deoxy-2-[18F] fluoro-D-glucose with positron emission tomography/computerized tomography (FDG PET/CT) in staging of patients with Pancoast tumors and to investigate the relationship between volume-based quantitative PET parameters and prognosis. MATERIALS AND METHODS: The authors retrospectively reviewed data of the 47 patients with Pancoast tumors who underwent initial staging by conventional imaging methods and FDG PET/CT. FDG-PET images were visually and quantitatively evaluated, and metabolic tumor volume (MTV), total lesion glycolysis, and maximum standardized uptake values of primary tumors were calculated. The correlations between quantitative PET parameters and tumor stages, as well as overall survival, were analyzed. RESULTS: By detecting unknown distant metastasis, PET/CT upstaged 21% of patients. The sensitivity and specificity for detection of lymphatic involvement were 100% and 83.75%, respectively. Having surgery (p = 0.01) and being at an early stage (p = 0.004) were the most predictive factors for overall survival. Although there was no significant correlation between quantitative PET parameters and overall survival, MTV was the most powerful discriminator for operability and preoperative staging (p < 0.05). CONCLUSIONS: FDG-PET imaging was found to be a valuable method for an accurate staging in the management of patients with Pancoast tumor. Having surgery and being at an early stage at presentation were found to be significant predictors for survival. Quantitative metabolic parameters may contribute to clarification of operable patient subgroups having an early disease stage with low MTV.

The role of FDG PET/CT in evaluation of mediastinal masses and neurogenic tumors of chest wall.

UNLABELLED: We evaluated the efficiency of FDG PET/CT for the differentiation of malignant from benign mediastinal masses and neurogenic tumors of chest-wall. METHODS: The 88 patients with chest wall-mediastinal masses who underwent examination before operation were retrospectively reviewed. Size, CT density (HU mean) and SUVmax of mediastinal and chest wall lesions were determined. Statistical differences of these parameters were compared between groups by Mann-Whitney U test. Receiver-operating characteristic curve (ROC) analysis with respect to SUVmax was performed to determine the best cutoff value for differentiating benign from malignant masses. RESULTS: The overall sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of PET/CT in detection of malignancy were 90%, 55.17%, 67%, 50.94% and 91.43%, respectively. The SUVmax, HU mean and size were higher in malignant cases (P < 0.05). To distinguish benign and malignant lesions, the cut off value of SUVmax was 4.67. The lesion SUVmax was significantly associated with the lesion size and lesion HU mean values (P < 0.05). The value of SUVmax and HU mean were higher in solid benign lesions than those of cystic benign lesions (P < 0.05). The lesion size was higher in cystic lesions (P = 0.000). The mean SUVmax was significantly higher in invasive thymomas than those of non-invasive forms (P = 0.029). CONCLUSION: FDG PET/CT may be complementary to conventional imaging methods for the evaluation of mediastinal and chest wall masses. PET/CT may reduce unnecessary invasive investigations for diagnosis in patients with nonavid or low avid FDG lesions. However confirmatory tissue sampling is required to confirm PET positive findings for the definite diagnosis.

FDG PET/CT Findings of Recurrent Respiratory Papillomatosis With Malignant Degeneration in the Lung.

Recurrent respiratory papillomatosis is a rare benign disease caused by HPV-6 or HPV-11. The tumors may rarely undergo malignant degeneration. We performed FDG PET/CT in a patient experiencing recurrent respiratory papillomatosis who had pulmonary involvement. Although squamous cell carcinoma was detected in one of the pulmonary masses, squamous metaplasia with dysplasia were detected in the other one. Intensity modulated radiation therapy was performed to treat the malignancy. Second FDG PET/CT was performed 15 months after radiotherapy.

Absence of the Right Internal Jugular Vein During Ultrasound-Guided Cannulation.

Cannulation of the internal jugular vein (IJV) may be diffucult because of anatomical variations. A 66-year-old female patient, who was in the intensive care unit, underwent ultrasound-guided cannulation of the right IJV. The right IJV could not be visualized by ultrasonography despite positional changes of the patient and Valsalva maneuvre. The left IJV was easily determined by ultrasonography and cannulated. Although the landmark technique may be sufficient for most of the central vein cannulations, the rate of anatomical variations and related complications is quite high. We point out that even if ultrasound cannot be used in real-time, the ultrasonographic confirmation during the pre-insertion period may be crucial for successful central vein cannulation.

18F-FDG PET/CT rarely provides additional information other than primary tumor detection in patients with pulmonary carcinoid tumors.

AIM: The purpose of this study was to assess the contribution of (18)F-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET)/Computed Tomography (CT) in detection and staging of pulmonary carcinoid tumors. METHODS: A total of 22 patients with pulmonary carcinoid tumors (14 typical, 8 atypical) were reviewed in this retrospective study. PET/CT images of all patients were evaluated for primary tumor as well as metastatic regional lymph nodes, bone and other distant metastases. PET/CT positivity of primary tumors was determined by visual interpretation. Tumor size, SUVmax and Hounsfield Unit (HU) values of the tumors were used to test for differences between tumor groups (typical carcinoids and atypical carcinoids). RESULTS: SUVmax of carcinoids ranged from 1.24 to 11.1 (mean, 5.0; median, 2.67). The mean largest diameter of primary tumors was 2.7 ± 1.3 cm, ranging from 1 to 5.5 cm. The overall sensitivity of FDG PET/CT for detection of pulmonary carcinoid tumors was 81.8%. Tumor size, SUVmax and Hounsfield Unit (HU) values of the atypical carcinoids were higher than those for typical carcinoids. However, the results were not statistically meaningful (P > 0.05). The sensitivity and specificity of FDG PET/CT in the detection of mediastinal and hilar lymph nodes metastases were 25% and 83% respectively. One patient had bone metastasis. CONCLUSION: Although FDG PET/CT can be a useful tool for the detection of pulmonary carcinoid tumors and distant metastasis, it cannot discriminate typical carcinoids from atypical ones and absence of an FDG avid lesion cannot exclude pulmonary carcinoid tumors. Moreover, PET/CT is not a reliable tool in the staging of mediastinal and hilar lymph nodes especially for those patients with typical carcinoids.

Integration of PET/CT in Current Diagnostic and Response Evaluation Methods in Patients with Tuberculosis.

Tuberculosis is a systemic disease that still affects many people. While pleural involvement is frequently observed in extrapulmonary tuberculosis, multiple skeletal system and articular involvements are quite rare. FDG PET imaging could be a promising diagnostic and treatment monitoring method, especially in complicated cases and if the other methods are inadequate. In this case study, we report a patient who was admitted with suspected malignancy and then diagnosed with tuberculosis pleuritis, lymphadenitis, spondylodiscitis, and sacroiliitis with specific symptoms; the response to anti-tuberculosis therapy was shown using FDG PET/CT.

Decreased metabolic uptake in tuberculous pericarditis indicating response to antituberculosis therapy on FDG PET/CT.

Early diagnosis and adequate treatment of tuberculosis are important for disease control and prevention of complication. However, diagnosing disease is frequently delayed because of difficulties of bacilli isolation or reproduction in cultures, and also, the decision of the efficiency of treatment sometimes can be impossible. FDG PET has become a promising imaging modality in the field of infection and inflammation, especially for the extension and severity of disease. Here, we describe an unusual case of tuberculous pericarditis that shows marked increased FDG uptake on initial scan, with decreasing metabolic activity on follow-up scan indicating response to antituberculosis therapy.

Integration of 2-deoxy-2-[18F] fluoro-D-glucose PET/CT into clinical management of patients with Wegener's granulomatosis.

OBJECTIVE: Wegener's granulomatosis (WG) is a rare disorder characterized by granulomatous necrotizing vasculitis which mainly affects small- and medium-sized vessels. While the classical triad of involvement is upper and lower respiratory system and glomerulonephritis, WG may involve any organ or system in the body. The aim of our study was to investigate the role of positron emission tomography/computerized tomography (PET/CT) both in the initial evaluation and follow-up of patients with WG. METHODS: We retrospectively evaluated PET/CT data from 13 patients (6 males; 7 females) with a mean age of 45 ± 12.4 years (range 28-63) who underwent either initial evaluation (n = 12) or response evaluation (n = 2) by conventional imaging methods and FDG with PET/CT. PET/CT images were both visually and quantitatively evaluated. The demographic data, clinical and laboratory findings of each patient were also recorded from the hospital files. RESULTS: Lung (n = 13), parapharyngeal space (n = 8), nose (n = 8), and ear (n = 3) were the most common disease sites detected on PET/CT. The entire initial evaluation patients had either solitary or multiple pulmonary nodular/mass lesions with marked increased FDG uptake (mean SUVmax 12 ± 4, range 3.53-19.51) on PET/CT. There was no significant pathological FDG uptake in patients consistent with complete treatment response after appropriate immunosuppressive therapy. PET/CT clearly demonstrated unexpected disease sites besides the respiratory system, with WG involvement except kidneys. Possibly due to physiological urinary excretion of FDG, urine analysis, BUN and creatinine levels were accepted still the best way for diagnosis of renal involvement. CONCLUSION: FDG with PET/CT is a valuable tool in the management of patients with WG for a more accurate clinical evaluation regarding disease extension and treatment response.