OBJECTIVE. This study aimed to evaluate the reproducibility of a new grading system for lumbar foraminal stenosis.MATERIALS AND METHODS. Four grades were developed for lumbar foraminal stenosis on the basis of sagittal MRI. Grade 0 refers to the absence of foraminal stenosis; grade 1 refers to mild foraminal stenosis showing perineural fat obliteration in the two opposing directions, vertical or transverse; grade 2 refers to moderate foraminal stenosis showing perineural fat obliteration in the four directions without morphologic change, both vertical and transverse directions; and grade 3 refers to severe foraminal stenosis showing nerve root collapse or morphologic change. A total of 576 foramina in 96 patients were analyzed (from L3–L4 to L5–S1). Two experienced radiologists independently assessed the sagittal MR images. Interobserver agreement between the two radiologists and intraobserver agreement by one reader were analyzed using kappa statistics.RESULTS. According to reader 1, grade 1 foraminal st...

Osteoid osteoma is characterized by an intracortical nidus with a variable amount of calcification, as well as cortical thickening, sclerosis, and bone marrow edema. When these findings are present, a diagnosis of osteoid osteoma is easily made. However, osteoid osteoma may display imaging findings that can be misleading, and it can be difficult to differentiate osteoid osteoma from other conditions such as infection, inflammatory and noninflammatory arthritis, and other tumors. In addition, stress fracture, intracortical abscess, intracortical hemangioma, chondroblastoma, osteoblastoma, and compensatory hypertrophy of the pedicle may mimic osteoid osteoma. To make the correct diagnosis, it is necessary to identify the nidus, and it is important to be familiar with the radiologic findings of osteoid osteoma and its mimics.

Magnetic resonance (MR) imaging is a powerful diagnostic tool that can be used to help evaluate spinal infection and to help distinguish between an infection and other clinical conditions. In most cases of spinal infection, MR images show typical findings such as vertebral endplate destruction, bone marrow and disk signal abnormalities, and paravertebral or epidural abscesses. However, it is not always easy to diagnose a spinal infection, particularly when some of the classic MR imaging features are absent or when there are unusual patterns of infectious spondylitis. Furthermore, noninfectious inflammatory diseases and degenerative disease may simulate spinal infection. It is necessary to be familiar with atypical MR imaging findings of spinal infection and features that may mimic spinal infection to avoid misdiagnosis and inappropriate treatment.

OBJECTIVE. The purpose of this study was to propose a new MRI grading system for cervical canal stenosis and to evaluate the reproducibility of the system. MATERIALS AND METHODS. Cervical canal stenosis was classified according to the T2-weighted sagittal images into the following grades: grade 0, absence of canal stenosis; grade 1, subarachnoid space obliteration exceeding 50%; grade 2, spinal cord deformity; and grade 3, spinal cord signal change. The MRI scans of 82 patients (37 men and 45 women; mean age, 65.2 years; range, 60–86 years) were independently analyzed by six radiologists. Interobserver and intraobserver agreements were analyzed using intraclass correlation coefficient (ICC), along with the percentage agreement and kappa statistics. RESULTS. The ICC for interobserver agreement was 0.716–0.802, indicating good-to-excellent agreement. For the distinction among the four grades, the percentage of agreement was 63–64% (κ = 0.60–0.62). The percentage of agreement for the presence of cervical can...

To prospectively evaluate the incidence of, characteristics of, and risk factors for pulmonary cement embolism after percutaneous vertebroplasty (PVP) in osteoporotic vertebral compression fractures (VCFs). Institutional review board approval and written informed consent were obtained. From June 2006 to September 2007, 75 patients (57 women, 18 men; mean age, 74.78 years; range, 48-93 years) who underwent 78 PVP sessions at 119 levels for osteoporotic VCFs were prospectively enrolled in this study. Computed tomographic (CT) scans of the chest and treated vertebrae were obtained after PVP. The presence, location, involved pulmonary arteries, number, and size of each pulmonary cement embolus were analyzed at CT. Possible risk factors were analyzed as follows: Age, injected cement volumes, and numbers of treated vertebrae were analyzed by using the Mann-Whitney U test; operators (radiologist or nonradiologist), level of treated vertebrae, guidance equipment, approach (uni- or bipedicular), presence of intravertebral vacuum clefts, and presence of paravertebral venous leakage were analyzed by using Pearson chi(2) and Fisher exact tests. Pulmonary cement emboli developed in 18 (23%) of 78 PVP sessions and were detected in the distal to third-order pulmonary arteries. Only cement leakage into the inferior vena cava showed a statistically significant relationship to pulmonary cement embolism (P = .03). A higher frequency of pulmonary cement embolism was noted for the absence of intravertebral vacuum clefts, for the bipedicular approach, and for a nonradiologist operator with C-arm fluoroscopy (P > .05). In osteoporotic VCFs, pulmonary cement embolism was detected in 23% of PVP sessions, developed in the distal to third-order pulmonary arteries, and was related to leakage into the inferior vena cava.