Objective: To investigate the detection and diagnostic efficacy of chest radiographs for ≤30 mm pulmonary nodules and the factors affecting them, and to compare the level of consistency among readers. Methods: A total of 43 patients with asymptomatic pulmonary nodules who consulted in Cancer Hospital, Chinese Academy of Medical Sciences from 2012 to 2014 and had chest CT and X-ray chest radiographs during the same period were retrospectively selected, and one nodule ≤30 mm was visible on chest CT images in the whole group (total 43 nodules in the whole group). One senior radiologist with more than 20 years of experience in imaging diagnosis reviewed CT images and recording the size, morphology, location, and density of nodules was selected retrospectively. Six radiologists with different levels of experience (2 residents, 2 attending physicians and 2 associate chief physicians independently reviewed the chest images and recorded the time of review, nodule detection, and diagnostic opinion. The CT imaging characteristics of detected and undetected nodules on X images were compared, and the factors affecting the detection of nodules on X-ray images were analyzed. Detection sensitivity and diagnosis accuracy rate of 6 radiologists were calculated, and the level of consistency among them was compared to analyze the influence of radiologists' seniority and reading time on the diagnosis results. Results: The number of nodules detected by all 6 radiologists was 17, with a sensitivity of detection of 39.5%(17/43). The number of nodules detected by ≥5, ≥4, ≥3, ≥2, and ≥1 physicians was 20, 21, 23, 25, and 28 nodules, respectively, with detection sensitivities of 46.5%, 48.8%, 53.5%, 58.1%, and 65.1%, respectively. Reasons for false-negative result of detection on X-ray images included the size, location, density, and morphology of the nodule. The sensitivity of detecting ≤30 mm, ≤20 mm, ≤15 mm, and ≤10 mm nodules was 46.5%-58.1%, 45.9%-54.1%, 36.0%-44.0%, and 36.4% for the 6 radiologists, respectively; the diagnosis accuracy rate was 19.0%-85.0%, 16.7%-6.5%, 18.2%-80.0%, and 0%-75.0%, respectively. The consistency of nodule detection among 6 doctors was good (Kappa value: 0.629-0.907) and the consistency of diagnostic results among them was moderate or poor (Kappa value: 0.350-0.653). The higher the radiologist's seniority, the shorter the time required to read the images. The reading time and the seniority of the radiologists had no significant influence on the detection and diagnosis results (P>0.05). Conclusions: The ability of radiographs to detect lung nodules ≤30 mm is limited, and the ability to determine the nature of the nodules is not sufficient, and the increase in reading time and seniority of the radiologists will not improve the diagnostic accuracy. X-ray film exam alone is not suitable for lung cancer diagnosis.
Humans ; Retrospective Studies ; Solitary Pulmonary Nodule/diagnostic imaging* ; Radiography ; Multiple Pulmonary Nodules/diagnostic imaging* ; Tomography, X-Ray Computed/methods* ; Lung Neoplasms/diagnostic imaging* ; Sensitivity and Specificity ; Radiographic Image Interpretation, Computer-Assisted/methods*

OBJECTIVE: To evaluate the influence of high-pitch mode (HPM) in dual-source computed tomography (DSCT) on the accuracy of three-dimensional (3D) volumetry for solid pulmonary nodules. MATERIALS AND METHODS: A lung phantom implanted with 45 solid pulmonary nodules (n = 15 for each of 4-mm, 6-mm, and 8-mm in diameter) was scanned twice, first in conventional pitch mode (CPM) and then in HPM using DSCT. The relative percentage volume errors (RPEs) of 3D volumetry were compared between the HPM and CPM. In addition, the intermode volume variability (IVV) of 3D volumetry was calculated. RESULTS: In the measurement of the 6-mm and 8-mm nodules, there was no significant difference in RPE (p > 0.05, respectively) between the CPM and HPM (IVVs of 1.2 +/- 0.9%, and 1.7 +/- 1.5%, respectively). In the measurement of the 4-mm nodules, the mean RPE in the HPM (35.1 +/- 7.4%) was significantly greater (p < 0.01) than that in the CPM (18.4 +/- 5.3%), with an IVV of 13.1 +/- 6.6%. However, the IVVs were in an acceptable range (< 25%), regardless of nodule size. CONCLUSION: The accuracy of 3D volumetry with HPM for solid pulmonary nodule is comparable to that with CPM. However, the use of HPM may adversely affect the accuracy of 3D volumetry for smaller (< 5 mm in diameter) nodule.
Humans ; Imaging, Three-Dimensional/instrumentation/*methods ; Lung/radiography ; Lung Neoplasms/*radiography ; Multiple Pulmonary Nodules/*radiography ; Phantoms, Imaging ; Solitary Pulmonary Nodule/*radiography ; Tomography, X-Ray Computed/instrumentation/*methods

The radiologic findings of a single nodule from Pneumocystis jirovecii pneumonia (PJP) have been rarely reported. We described a case of granulomatous PJP manifesting as a solitary pulmonary nodule with a halo sign in a 69-year-old woman with diffuse large B cell lymphoma during chemotherapy. The radiologic appearance of the patient suggested an infectious lesion such as angioinvasive pulmonary aspergillosis or lymphoma involvement of the lung; however, clinical manifestations were not compatible with the diseases. The nodule was confirmed as granulomatous PJP by video-assisted thoracoscopic surgery biopsy.
Aged ; Antibodies, Monoclonal, Murine-Derived/adverse effects/therapeutic use ; Antineoplastic Agents/adverse effects/therapeutic use ; Antineoplastic Combined Chemotherapy Protocols/adverse effects/therapeutic use ; Biopsy/methods ; Cyclophosphamide/adverse effects/therapeutic use ; Doxorubicin/adverse effects/therapeutic use ; Female ; Humans ; Lymphoma, Large B-Cell, Diffuse/drug therapy/microbiology ; Pneumocystis jirovecii/pathogenicity ; Pneumonia, Pneumocystis/*diagnosis/*radiography ; Positron-Emission Tomography ; Prednisone/adverse effects/therapeutic use ; Solitary Pulmonary Nodule/*microbiology ; Thoracic Surgery, Video-Assisted ; Tomography, X-Ray Computed ; Vincristine/adverse effects/therapeutic use

Leflunomide, a disease-modifying antirheumatic drug, is effective for rheumatoid arthritis as monotherapy or combination therapy with methotrexate. The most common adverse effects are diarrhea, dyspepsia, nausea, abdominal pain, oral ulcer, hepatotoxicity, skin rash, hypertension, weight loss, and interstitial lung disease. The occurrence of pulmonary cryptococcosis in leflunomide treatment has not been reported in Korea. A 74-year-old woman was admitted to hospital due to asymptomatic pulmonary nodule. She was diagnosed rheumatoid arthritis and treated with leflunomide 5 months ago due to treatment failure with methotrexate, hydroxychloroquine, and sulfasalazine. Chest radiograph and computed tomography showed solitary pulmonary nodule in her right lower lung. Pulmonary cryptococcosis was confirmed by needle biopsy of lung stained with Gomori methenamine silver and mucicarmine. The lesion was improved after antifungal therapy for 3 months.
Abdominal Pain ; Aged ; Arthritis, Rheumatoid* ; Biopsy, Needle ; Cryptococcosis* ; Diarrhea ; Dyspepsia ; Exanthema ; Female ; Humans ; Hydroxychloroquine ; Hypertension ; Korea ; Lung ; Lung Diseases, Interstitial ; Methenamine ; Methotrexate ; Nausea ; Oral Ulcer ; Radiography, Thoracic ; Solitary Pulmonary Nodule ; Sulfasalazine ; Treatment Failure ; Weight Loss

Preoperative localization is necessary prior to video assisted thoracoscopic surgery for the detection of small or deeply located lung nodules. We compared the localization ability of a mixture of lipiodol and methylene blue (MLM) (0.6 mL, 1:5) to methylene blue (0.5 mL) in rabbit lungs. CT-guided percutaneous injections were performed in 21 subjects with MLM and methylene blue. We measured the extent of staining on freshly excised lung and evaluated the subjective localization ability with 4 point scales at 6 and 24 hr after injections. For MLM, radio-opacity was evaluated on the fluoroscopy. We considered score 2 (acceptable) or 3 (excellent) as appropriate for localization. The staining extent of MLM was significantly smaller than methylene blue (0.6 vs 1.0 cm, P<0.001). MLM showed superior staining ability over methylene blue (2.8 vs 2.2, P=0.010). Excellent staining was achieved in 17 subjects (81%) with MLM and 8 (38%) with methylene blue (P=0.011). An acceptable or excellent radio-opacity of MLM was found in 13 subjects (62%). An appropriate localization rate of MLM was 100% with the use of the directly visible ability and radio-opacity of MLM. MLM provides a superior pulmonary localization ability over methylene blue.
Animals ; Ethiodized Oil/*administration & dosage ; Fluoroscopy ; Injections, Subcutaneous ; Lung/*radiography/surgery ; Methylene Blue/*administration & dosage ; Preoperative Care ; Rabbits ; Solitary Pulmonary Nodule/*surgery ; Staining and Labeling/methods ; Thoracic Surgery, Video-Assisted/*methods ; Thoracoscopy/methods ; Tomography, X-Ray Computed

OBJECTIVE: To compare the segmentation capability of the 2 currently available commercial volumetry software programs with specific segmentation algorithms for pulmonary ground-glass nodules (GGNs) and to assess their measurement accuracy. MATERIALS AND METHODS: In this study, 55 patients with 66 GGNs underwent unenhanced low-dose CT. GGN segmentation was performed by using 2 volumetry software programs (LungCARE, Siemens Healthcare; LungVCAR, GE Healthcare). Successful nodule segmentation was assessed visually and morphologic features of GGNs were evaluated to determine factors affecting segmentation by both types of software. In addition, the measurement accuracy of the software programs was investigated by using an anthropomorphic chest phantom containing simulated GGNs. RESULTS: The successful nodule segmentation rate was significantly higher in LungCARE (90.9%) than in LungVCAR (72.7%) (p = 0.012). Vascular attachment was a negatively influencing morphologic feature of nodule segmentation for both software programs. As for measurement accuracy, mean relative volume measurement errors in nodules > or = 10 mm were 14.89% with LungCARE and 19.96% with LungVCAR. The mean relative attenuation measurement errors in nodules > or = 10 mm were 3.03% with LungCARE and 5.12% with LungVCAR. CONCLUSION: LungCARE shows significantly higher segmentation success rates than LungVCAR. Measurement accuracy of volume and attenuation of GGNs is acceptable in GGNs > or = 10 mm by both software programs.
Adult ; Aged ; *Algorithms ; Female ; Humans ; Lung Neoplasms/diagnosis ; Male ; Middle Aged ; Multidetector Computed Tomography/*methods ; *Phantoms, Imaging ; Reproducibility of Results ; Retrospective Studies ; *Software ; Solitary Pulmonary Nodule/*radiography

OBJECTIVE: To determine the optimum low dose (LD) digital tomosynthesis (DT) setting, and to compared the image quality of the LD DT with that of the standard default (SD) DT. MATERIALS AND METHODS: Nine DT settings, by changing tube voltage, copper filter, and dose ratio, were performed for determining the LD setting. Among combinations of DT setting, a condition providing the lowest radiation dose was determined. Eighty artificial nodules less than 1 cm in diameter (subcentimeter nodules: 40, micronodules less than 4 mm: 40) were attached to a Styrofoam and a diaphragm of the phantom. Among these, 38 nodules were located at the periphery of the lung (thin area) and 42 nodules were located at the paravertebral or sub-diaphragmatic area (thick area). Four observers counted the number of nodules detected in the thick and thin areas. The detection sensitivity in SD and LD settings were calculated separately. Data were analyzed statistically. RESULTS: The lowest LD setting was a combination of 100 kVp, 0.3 mm additional copper filter, and a 1 : 5 dose ratio. The effective dose for the LD and SD settings were 62 microSv and 140 microSv, separately. A 56.7% dose reduction was achieved in the LD setting compared with the SD setting. Detection sensitivities were not different between the SD and the LD settings except between observers 1 and 2 for the detection of micronodules in the thick area. CONCLUSION: LD DT can be effective in nodule detection bigger than 4 mm without a significant decrease in image quality compared with SD DT.
Diagnosis, Computer-Assisted/*methods ; Humans ; Lung Neoplasms/radiography ; *Phantoms, Imaging ; *Radiation Dosage ; Radiographic Image Enhancement/*methods ; Sensitivity and Specificity ; Solitary Pulmonary Nodule/radiography

OBJECTIVE: To describe our initial experience with CT-guided percutaneous barium marking for the localization of small pulmonary nodules prior to video-assisted thoracoscopic surgery (VATS). MATERIALS AND METHODS: From October 2010 to April 2011, 10 consecutive patients (4 men and 6 women; mean age, 60 years) underwent CT-guided percutaneous barium marking for the localization of 10 small pulmonary nodules (mean size, 7.6 mm; range, 3-14 mm): 6 pure ground-glass nodules, 3 part-solid nodules, and 1 solid nodule. A 140% barium sulfate suspension (mean amount, 0.2 mL; range, 0.15-0.25 mL) was injected around the nodules with a 21-gauge needle. The technical details, surgical findings and pathologic features associated with barium localizations were evaluated. RESULTS: All nodules were marked within 3 mm (mean distance, 1.1 mm; range, 0-3 mm) from the barium ball (mean diameter, 9.6 mm; range, 8-16 mm) formed by the injected barium suspension. Pneumothorax occurred in two cases, for which one needed aspiration. However, there were no other complications. All barium balls were palpable during VATS and visible on intraoperative fluoroscopy, and were completely resected. Both the whitish barium balls and target nodules were identifiable in the frozen specimens. Pathology revealed one invasive adenocarcinoma, five adenocarcinoma-in-situ, two atypical adenomatous hyperplasias, and two benign lesions. In all cases, there were acute inflammations around the barium balls which did not hamper the histological diagnosis of the nodules. CONCLUSION: CT-guided percutaneous barium marking can be an effective, convenient and safe pre-operative localization procedure prior to VATS, enabling accurate resection and diagnosis of small or faint pulmonary nodules.
Adult ; Aged ; Barium Sulfate/*diagnostic use ; *Contrast Media ; Female ; Humans ; Lung Neoplasms/radiography/*surgery ; Male ; Middle Aged ; *Radiography, Interventional ; Solitary Pulmonary Nodule/radiography/*surgery ; *Thoracic Surgery, Video-Assisted ; *Tomography, X-Ray Computed

The solitary pulmonary nodule on chest X-ray (CXR) is a common problem in pulmonary medicine. Its presence raises the question of lung cancer. As five-year survival after resection of a solitary bronchogenic carcinoma can be as high as 80%, prompt evaluation is crucial. This should begin with a cancer risk assessment based on clinical and radiographic factors. The risk and benefits of surgery should next be assessed, and together with the patient's preferences, a management plan can be decided upon. Surgery is recommended for patients at high risk of malignancy with a low surgical risk, while careful observation is adopted for patients at low risk of malignancy coupled with a high surgical risk. Further diagnostic tests may be warranted to aid in this decision process. Although CXR is not useful for lung cancer screening, low-dose computed tomography imaging is increasingly recommended for individuals at high risk for lung cancer.
Aged ; Diagnostic Imaging ; methods ; Humans ; Lung Diseases ; diagnosis ; Lung Neoplasms ; diagnosis ; Middle Aged ; Pulmonary Medicine ; methods ; Radiography ; methods ; Radiography, Thoracic ; methods ; Risk Assessment ; methods ; Risk Factors ; Solitary Pulmonary Nodule ; diagnosis

As the detection and characterization of lung nodules are of paramount importance in thoracic radiology, various tools for making a computer-aided diagnosis (CAD) have been developed to improve the diagnostic performance of radiologists in clinical practice. Numerous studies over the years have shown that the CAD system can effectively help readers identify more nodules. Moreover, nodule malignancy and the response of malignant lung tumors to treatment can also be assessed using nodule volumetry. CAD also has the potential to objectively analyze the morphology of nodules and enhance the workflow during the assessment of follow-up studies. Therefore, understanding the current status and limitations of CAD for evaluating lung nodules is essential to effectively apply CAD in clinical practice.
Clinical Trials as Topic ; *Diagnosis, Computer-Assisted ; Diagnosis, Differential ; Humans ; Lung Neoplasms/pathology/*radiography ; Predictive Value of Tests ; Radiographic Image Interpretation, Computer-Assisted ; Radiography, Thoracic ; Sensitivity and Specificity ; Solitary Pulmonary Nodule/pathology/*radiography ; *Tomography, X-Ray Computed