OBJECTIVE: To evaluate how changes in lung volume affect volumetric measurements of lung nodules using a multi-detector row CT. MATERIALS AND METHODS: Ten subjects with asthma or chronic bronchitis who had one or more lung nodules were included. For each subject, two sets of CT images were obtained at inspiration and at expiration. A total of 33 nodules (23 nodules > or = 3 mm) were identified and their volume measured using a semiautomatic volume measurement program. Differences between nodule volume on inspiration and expiration were compared using the paired t-test. Percent differences, between on inspiration and expiration, in nodule attenuation, total lung volume, whole lung attenuation, and regional lung attenuation, were computed and compared with percent difference in nodule volume determined by linear correlation analysis. RESULTS: The difference in nodule volume observed between inspiration and expiration was significant (p < 0.01); the mean percent difference in lung nodule volume was 23.1% for all nodules and for nodules > or = 3 mm. The volume of nodules was measured to be larger on expiration CT than on inspiration CT (28 out of 33 nodules; 19 out of 23 nodules > or = 3 mm). A statistically significant correlation was found between the percent difference of lung nodule volume and lung volume or regional lung attenuation (p < 0.05) for nodules > or = 3 mm. CONCLUSION: Volumetric measurements of pulmonary nodules were significantly affected by changes in lung volume. The variability in this respiration-related measurement should be considered to determine whether growth has occurred in a lung nodule.
Tomography, X-Ray Computed/*methods ; Middle Aged ; Male ; Humans ; Female ; Coin Lesion, Pulmonary/pathology/*radiography ; Bronchitis/radiography ; Asthma/radiography ; Adult

PURPOSE: To design and develop a World Wide Web-based education program that will allow trainees to interactively learn and improve the diagnostic capability of detecting pulmonary nodules on chest radiographs. MATERIALS AND METHODS: Chest radiographs with known diagnosis were retrieved and selected from our institutional clinical archives. A database was constructed by sorting radiographs into three groups: normal, nodule, and false positive (i.e., nodule-like focal opacity). Each nodule was assigned with the degree of detectability: easy, intermediate, difficult, and likely missed. Nodules were characterized by their morphology (well-defined, ill-defined, irregular, faint) and by other associated pathologies or potentially obscuring structures. The Web site was organized into four sections: study, test, record and information. RESULTS: The Web site allowed a user interactively to undergo the training section appropriate to the user's diagnostic capability. The training was enhanced by means of clinical and other pertinent radiological findings included in the database. The outcome of the training was tested with clinical test radiographs that presented nodules or false positives with varying diagnostic difficulties. CONCLUSION: A Word Wide Web-based education program is a promising technique that would allow trainees to interactively learn and improve the diagnostic capability of detecting and characterizing pulmonary nodules.
Diagnosis ; Education* ; Internet ; Pathology ; Radiography, Thoracic* ; Thorax*

Tolvaptan reduces height-adjusted total kidney volume (htTKV) and renal function decline in autosomal dominant polycystic kidney disease (ADPKD). This study was aimed at investigating the efficacy and safety of tolvaptan in Korean patients with ADPKD during the titration period. Methods: This study is a multicenter, single-arm, open-label phase 4 study. We enrolled 108 patients with ADPKD (age, 19–50 years) with an estimated glomerular filtration rate (eGFR) of >30 mL/min/1.73 m2 and factors defined as indicative of rapid disease progression. After tolvaptan titration, we evaluated efficacy and side effects and assessed factors associated with the effects. Results: After titration for 4 weeks, eGFR and htTKV decreased by 6.4 ± 7.9 mL/min/1.73 m2 and 16 ± 45 mL/m, respectively. No serious adverse drug reactions were observed during the titration period. The greatest eGFR decline was observed in the first week, with a starting tolvaptan dose of 45 mg. Multivariate linear regression for htTKV decline showed that the greater the change in urine osmolality (Uosm), the greater the decrease in htTKV (β, 0.436; p = 0.009) in the 1D group stratified by the Mayo Clinic image classification. Higher baseline eGFR was related to a higher htTKV reduction rate in the 1E group (β, –0.642; p = 0.009). Conclusion: We observed short-term effects and safety during the tolvaptan titration period. The decline of htTKV can be predicted as a short-term effect of tolvaptan by observing Uosm changes from baseline to end of titration in 1D and baseline eGFR in 1E groups.