[Fundamental Study of Inflation Pressure Resistance in an Angiographical Tube].

This study was designed to clarify the relation between the pressure resistance of an angiographical tube and the amount of contrast medium injected under a connected microcatheter used for interventional radiology (IVR). We investigated the injection pressure and the expansion rate at the center of the tube during contrast enhancement by setting the power injector to 1200 PSI pressure, with 2.0 ml/s injection speed, 10 ml injection volume, 5.0 s injection time, and 0 s rise time for tubes with different pressure resistance performance (low or high). Then we examined the amount of contrast medium material discharged from the microcatheter. The low-pressure resistant tube (less than 140 PSI) injection pressure exceeded the pressure performance. The expansion rate increased to 49%, presenting a risk of rupture. The injection pressure of the high-pressure resistant tube (less than 1200 PSI) was within the pressure-resistance performance. The expansion rate increased to 38%. However, when the contrast medium discharge amount contributing to the image was measured within the injection time under the condition of 10 ml injection for 5.0 s, the former was 2.3 ml and the latter was 4.2 ml. The entire amount was not discharged during the injection period. It became apparent that it is discharged in drips after some time. Results show that the tube expansion caused retention of the contrast medium inside, which decreases the actual amount of the injected contrast medium. From the results, we infer the possibility of preventing reduction of the injected contrast medium amount attributable to expansion.

In vivo 3-dimensional analysis of scapular and glenohumeral kinematics: comparison of symptomatic or asymptomatic shoulders with rotator cuff tears and healthy shoulders.

BACKGROUND: Alteration in shoulder kinematics has been suggested as one cause of symptoms in shoulders with rotator cuff tears (RCTs). However, only a few studies comparing symptomatic and asymptomatic RCTs using kinematic analysis have been performed. The purpose of this study was to compare 3-dimensional (3D) scapular and glenohumeral kinematics during scapular-plane abduction among symptomatic RCTs, asymptomatic RCTs, and healthy shoulders. METHODS: This study included 7 healthy shoulders in subjects with a mean age of 62 years, 5 symptomatic RCTs in subjects with a mean age of 70 years, and 7 asymptomatic RCTs in subjects with a mean age of 67 years. All shoulders with RCTs had medium-sized tears (1-3 cm in the coronal plane) that were confirmed with magnetic resonance imaging. Biplane fluoroscopic images during scapular-plane abduction were recorded, and computed tomography-derived 3D bone models were matched with the silhouettes of the bones on the fluoroscopic images using 3D/2-dimensional model-image registration techniques. Angular values of the scapula and glenohumeral kinematics were compared among the 3 groups. RESULTS: Posterior tilt of the scapula was significantly smaller in the symptomatic RCTs (3.1° ± 1.8°) than in healthy shoulders (10.4° ± 0.8°) (P = .049). The humerus of the symptomatic shoulders was less externally rotated relative to the scapula throughout the activity than the healthy shoulders and asymptomatic RCTs (P = .006 and P = .028 respectively). However, there were no kinematic differences between the asymptomatic RCTs and healthy shoulders. CONCLUSION: Kinematic changes in symptomatic RCTs might be associated with development of symptoms. Improvement of these kinematic changes may be a key to successful conservative treatment for symptomatic RCTs.

A case of isolated peripheral pulmonary artery branch stenosis associated with multiple pulmonary artery aneurysms.

Selective right pulmonary arteriography and 3-dimensional computed tomography revealed multiple severe stenoses of the peripheral pulmonary artery associated with poststenotic aneurysms in a 65-year-old woman. She was referred to the hospital for evaluation of dry cough, gradually increasing dyspnea and multiple nodular shadows on a chest radiograph. Echocardiography and cardiac catheterization showed severe pulmonary hypertension, though other structural heart diseases or well-characterized congenital syndromes were ruled out. She was diagnosed as isolated peripheral pulmonary artery branch stenosis. Recent advances in CT technology enable a less-invasive assessment of pulmonary artery, and can be useful in the management of pulmonary arterial hypertension.

Retrospective ECG-gated left ventriculography using multislice CT following left ventricular bolus injection and evaluation of its utility and motion artifact at every cardiac phase.

Following left ventricular bolus injection of contrast material, multislice CT scanning was performed. With retrospective ECG-gated reconstruction, we could acquire volume data for the heart at any cardiac phase and selectively depict only the left ventricle and aorta with maximum intensity projection. Temporal resolution of multislice CT was not sufficient to eliminate motion artifact except just before atrial contraction periods.

Complications of pulmonary vein isolation by catheter ablation evaluated by ECG-gated multislice computed tomography.

As pulmonary vein (PV) isolation by catheter ablation for paroxysmal atrial fibrillation may cause PV luminal stenosis, digital subtraction angiography or magnetic resonance imaging have been used to evaluate the lumen of the PV. Electrocardiogram-gated multislice computed tomography can evaluate the lumen of the PV from any plane desired after acquisition with excellent spatial resolution. It can also evaluate hyperplasia of soft tissue around the lumen of the PV, which cannot be evaluated by digital subtraction angiography, and may thus serve as an indicator of complications or even the effectiveness of this treatment.