Biomedical subjects

Masatake Imai

Publications and source records attributed to Masatake Imai.

2 recordsLinked to original sources

PubMed2004

Transthoracic CT-guided biopsy with multiplanar reconstruction image improves diagnostic accuracy of solitary pulmonary nodules.

OBJECTIVE: To evaluate the utility of multiplanar reconstruction (MPR) image for CT-guided biopsy and determine factors of influencing diagnostic accuracy and the pneumothorax rate. MATERIALS AND METHODS: 390 patients with 396 pulmonary nodules underwent transthoracic CT-guided aspiration biopsy (TNAB) and transthoracic CT-guided cutting needle core biopsy (TCNB) as follows: 250 solitary pulmonary nodules (SPNs) underwent conventional CT-guided biopsy (conventional method), 81 underwent CT-fluoroscopic biopsy (CT-fluoroscopic method) and 65 underwent conventional CT-guided biopsy in combination with MPR image (MPR method). Success rate, overall diagnostic accuracy, pneumothorax rate and total procedure time were compared in each method. Factors affecting diagnostic accuracy and pneumothorax rate of CT-guided biopsy were statistically evaluated. RESULTS: Success rates (TNAB: 100.0%, TCNB: 100.0%) and overall diagnostic accuracies (TNAB: 96.9%, TCNB: 97.0%) of MPR were significantly higher than those using the conventional method (TNAB: 87.6 and 82.4%, TCNB: 86.3 and 81.3%) (P < 0.05). Diagnostic accuracy were influenced by biopsy method, lesion size, and needle path length (P < 0.05). Pneumothorax rate was influenced by pathological diagnostic method, lesion size, number of punctures and FEV1.0% (P < 0.05). CONCLUSION: The use of MPR for CT-guided lung biopsy is useful for improving diagnostic accuracy with no significant increase in pneumothorax rate or total procedure time.

Adolescent↗

PubMed2003

Three-dimensional treatment planning using electrocardiographically gated multi-detector row CT.

PURPOSE: Information concerning the amount and nature of target motion is essential for the determination of internal margin size. However, there are few published reports outlining the motion with heart and aortic pulsation. We introduce a method for three-dimensional radiation treatment planning (3D-RTP) by using electrocardiographically (ECG) gated spiral scanning with a four-section CT system. We describe a new approach to visualize internal organ motion resulting from cardiac motion with ECG gated multidetector row CT. MATERIALS AND METHODS: Five patients with lung or liver tumors were studied with a multidetector row CT system under shallow inspiration breath-holding. With retrospective ECG gating, only data acquired within a predefined interval of the cardiac cycle are used for image reconstruction. All reconstructed image data at diastolic and systolic phases of the cardiac cycle were transferred to the 3D-RTP system. The shift of the internal organs between the cardiac cycles was evaluated. RESULTS: Cardiac contraction influences anterior thorax, pulmonary peripheral vessels, and liver position, in addition to locations near the heart. Apparent movements more than 5 mm between diastolic and systolic phases were observed in the left ventricle, right atrium, and superior vena cava. Two-phase imaging was useful for showing the movement of internal organs during cardiac contraction under breath-holding. CONCLUSIONS: Spatial information using ECG-gated CT has the potential to determine the planning target volume of moving lung and liver tumors more precisely than conventional CT planning.

Computer Systems↗