Initial experience of percutaneous vertebroplasty using single-plane C-arm fluoroscopy for guidance.

PURPOSE: The purpose of this study was to evaluate the feasibility and safety of percutaneous vertebroplasty (PVP) using single-plane C-arm fluoroscopy. MATERIALS AND METHODS: Lesions in the present study all comprised compression fractures with intact pedicles. A polymethylmethacrylate (PMMA) mixture was injected by the transpedicular approach under C-arm fluoroscopy using a lateral projection. Before and after PVP, the pain score was determined using visual analog scale methods. RESULTS: Between June 2002 and May 2004, we performed 31 PVPs in 17 patients during 22 treatment sessions. Underlying pathology comprised neoplasm-related compression fracture (n=9) and fractures attributed to osteoporosis (n=8). Mean pain score was 8.0 (range, 4.5-10) immediately before PVP, and 1.9 (range, 0-7) at 24 h after PVP. Mean time needed to perform PVP was 59 min. Mean time to approach a pedicle was 36 min (range, 20 min for 1 pedicle to 110 min for 3 pedicles). No complications requiring surgical intervention or exacerbating conditions beyond pre-treatment levels were noted. CONCLUSION: PVP using single-plane C-arm fluoroscopy for guidance is feasible, safe, and quick.

123I-MIBG myocardial scintigraphy in patients with "takotsubo" cardiomyopathy.

UNLABELLED: The clinical characteristics of reversible left ventricular dysfunction due to "takotsubo" cardiomyopathy have been described, but the origin of this condition remains unclear. This study investigated (123)I-metaiodobenzlguanidine ((123)I-MIBG) myocardial scintigraphy in patients with takotsubo cardiomyopathy. METHODS: Eight consecutive patients with takotsubo cardiomyopathy were studied. Left ventricular wall motion was monitored by echocardiography until wall motion normalized. (123)I-MIBG myocardial scintigrams were performed within 3 d of admission (0 mo) and after the improvement of left ventricular dysfunction (3 mo). Early images were obtained at 30 min after radioisotope injection and delayed images were obtained after 4 h. The heart-to-mediastinum ratio (H/M ratio) and the washout rate were calculated. RESULTS: The mean left ventricular ejection fraction improved significantly (from 42.8% +/- 8.7% to 66.5% +/- 7.9%; P < 0.0001) and normalized after 19.4 +/- 5.4 hospital days. The early H/M ratio was significantly higher than the late ratio at 0 mo (2.16 +/- 0.25 vs. 1.89 +/- 0.24, respectively; P < 0.05), but not at 3 mo. The washout rate was significantly greater at 0 mo than at 3 mo (39.1% +/- 10.2% vs. 25.4% +/- 6.3%, respectively; P < 0.05). CONCLUSION: In patients with takotsubo cardiomyopathy, initial (123)I-MIBG myocardial scintigraphy depicted a unique pattern of ventricular asynergy and indicated the existence of cardiac sympathetic hyperactivity, although coronary blood flow was maintained. These findings strongly suggest that takotsubo cardiomyopathy could be caused by neurogenic myocardial stunning.

Comparison of axial high-resolution CT and thin-section multiplanar reformation (MPR) for diagnosis of diseases of the pulmonary parenchyma: preliminary study in 49 patients.

PURPOSE: We evaluated the diagnostic utility of coronal multiplanar reformation (MPR) images produced by multi-detector row CT in diffuse and focal pulmonary parenchymal disease. MATERIALS AND METHODS: A phantom study was conducted comparing spatial and low-contrast resolutions of axial high-resolution CT (HRCT) and coronal MPR. Non-spiral axial HRCT was performed with 2-mm collimation, and spiral CT was performed with 1-mm collimation and 8:1 pitch, from which MPR images were produced at 1.9-mm thickness and 5-mm intervals. Forty-nine patients were included in the clinical study. Three reviewers independently assessed the lesion conspicuity and disease extent on both axial HRCT and coronal MPR images, and the diagnostic utility of the coronal images was evaluated. Two reviewers subsequently assessed axial and coronal images separately, and the extent of abnormalities shown by each was compared. RESULTS: In phantom study, coronal MPR images were inferior to axial images but were considered adequate for clinical use. In clinical study, the image quality of MPR was regarded as good for observation of the lung parenchyma in all cases. The mean percentage of abnormalities for which 3 reviewers determined coronal MPR images as superior or additional information available was 22.1%, whereas 72.4% was regarded as comparable and 5.5% as inferior to axial images. Interobserver agreement was good (weighted kappa statistics 0.45-0.61). The extent of abnormality was judged to be shown equally on the axial and MPR images with good interobserver agreement (kappa statistics 0.63). CONCLUSION: Coronal MPR images may have an additional role to axial HRCT images in the clinical interpretation of lung parenchymal abnormalities.

Axial loading with hyperflexion injury to the atlas resulting in crushed lateral masses.

A 40-year-old man was involved in an ATV accident, in which he landed on the top of his head. There was no neurological deficit. A plain radiograph showed prevertebral soft tissue swelling at the atlas and axis level. Computed tomography (CT) demonstrated vertical fractures of the anterior aspects of both lateral masses of the atlas, extending to the junction of the lateral mass with the anterior arch bilaterally. There was no lateral offset of the lateral masses. The mechanism of injury is believed to be axial loading along with hyperflexion.

Horizontal fracture of the anterior arch of the atlas associated with a congenital cleft of the anterior arch.

We report a rare combination of a horizontal fracture of the anterior arch of the atlas associated with a congenital cleft of the anterior arch. Sagittally reformatted computed tomography (CT) images demonstrated a fracture of the anterior arch of the atlas and a type II odontoid process fracture. There was also a smoothly marginated midline cleft of the anterior arch just above the fracture consistent with a congenital variant. 3D CT images were helpful in the evaluation of the fractures and the developmental variant. Magnetic resonance imaging showed a spinal cord injury. The patient underwent posterior C1-C2 fusion.

Reversible left ventricular dysfunction "takotsubo" cardiomyopathy related to catecholamine cardiotoxicity.

An 80-year-old female was admitted for a persistent consciousness disturbance. Electrocardiography revealed ST-segment elevation in leads II, III, aVf, and V3-V6. Coronary angiography demonstrated normal arteries, while left ventriculography revealed asynergy of apical akinesis and basal hyperkinesis. The creatinine kinase and creatinine kinase MB levels were not elevated after the initial measurement on admission. The diffuse ST-segment elevation reached a maximum level 24 hours after admission. In leads V3-V6, ST-segment elevation continued for 48 hours, and was followed-up by deep inverted T waves. Within 24 days, the asynergy improved without any specific treatment, but the giant negative T waves were present on the electrocardiogram. The plasma norepinephrine and brain natriuretic peptide levels on the first hospital day were 2.9ng/mL and 906pg/mL, respectively. The left ventricular dysfunction appeared to be induced by the exposure to high-level plasma catecholamines. (123)I-metaiodobenzyl guanidine scintigraphy also revealed transient dysfunction of the cardiac catecholamine dynamics.

Air trapping on CT of patients with pulmonary embolism.

OBJECTIVE: We evaluated the relationship of air trapping to mosaic perfusion in patients with pulmonary embolism. SUBJECTS AND METHODS: Forty-one consecutive patients with suspected pulmonary embolism underwent expiratory CT followed by helical CT angiography. After excluding 12 patients who had airway disease or were smokers, we divided the patients into two groups: those with (n = 15) and without (n = 14) pulmonary embolism. For each patient, six expiratory images were evaluated for the presence of air trapping, and the corresponding six images from CT angiography were evaluated for the presence of mosaic perfusion. Clot locations were assessed on CT angiography and were correlated with the presence of air trapping and mosaic perfusion. RESULTS: In patients with pulmonary embolism, mosaic perfusion was identified in 32 areas (seven patients, 46.7%), and air trapping was identified 68 areas (nine patients, 60%). Of the 32 areas of mosaic perfusion, 23 areas (71.9%) showed air trapping on expiratory CT scans. Of the 68 areas with air trapping on expiratory scans, 23 areas (33.8%) showed mosaic perfusion on inspiratory scans, and 44 areas (64.7%) had clots in the arteries leading to them. Clots were more frequently identified in areas of lower attenuation on inspiratory CT scans and air trapping (21/23) than in those of normal attenuation on inspiratory CT scans and air trapping (23/45) (p < 0.005). Only one patient without pulmonary embolism had air trapping (p < 0.005). CONCLUSION: Air trapping is common in pulmonary embolism and may be the cause of mosaic perfusion. Air trapping can be seen distal to vessels not showing pulmonary embolism.