Humeral head ossification center in congenital heart disease.

The objective of this study was to evaluate the ossification (visualization) of proximal humeral ossification center (PHOC) which may indicate bone growth in infants with acyanotic and cyanotic congenital heart disease (HD) compared to normal infants. The medical records and chest radiographs within 3 months after birth of infants who were diagnosed as congenital HD by echocardiography or cardiac catheterization from 1989 to 1999 were reviewed. The PHOC was recorded from chest radiograph as presence or absence in every one-month interval since birth. In all cases, the corrected age of 0 month was defined as 40 weeks post conception. We used a study of 260 normal Korean infants as the normal population in this study. We found that from 67 cases enrolled in this study; 10 cases were excluded because of lack of complete medical records and sequential chest radiographs. In the remaining 57 cases, the average gestational age of the infants was 38.1 +/- 2.7 weeks and the average birth weight was 2860.5 +/- 597.7 grams. Female to male ratio was 1.28:1. The infants were classified by gestational age as term (75.4%) and pre-term (24.6%). Types of congenital HD were diagnosed from echocardiogram (96.5%) and cardiac catheterization (3.5%) of cases; and were divided as acyanotic HD (64.9%) and cyanotic HD (35.1%). The ossification of PHOC in acyanotic full-term infants at 0, 1, 2, and 3 months was 24.0 per cent, 32.0 per cent, 72.0 per cent and 88.0 per cent; in cyanotic full-term infants it was 27.8 per cent, 33.3 per cent, 77.8 per cent, and 94.4 per cent; and in acyanotic pre-term infants was 8.3 per cent, 8.3 per cent, 25.0 per cent, and 41.7 per cent, respectively. There were 2 cyanotic pre-term infants who did not show ossification of PHOC until 3 months. In full-term infants with both types of HD; the appearance of PHOC was significantly later than normal at 1 month corrected age (p = 0.000002) but not significant at 0, 2, and 3 months (p > 0.05); whereas, in pre-term infants with acyanotic HD, the appearance was later than normal at 1, 2, and 3 months (p = 0.02, p = 0.01, and p = 0.0002, respectively). We concluded that the ossification of PHOC is significantly later than normal in pre-term infants with congenital HD, but not significant in full-term infants with congenital HD.

False-negative meniscal tear in MR imaging using non fat-suppressed techniques.

Magnetic resonance (MR) imaging of menisci has a diagnostic accuracy of more than 90 per cent when the images are properly obtained. Errors in the interpretation of MR images may be related to many problems, resulting in false positive or false negative readings. We conducted this study to evaluate the prevalence of false negative results, using arthroscopy as gold standard. Matched MR imaging (performed before July 1997) and arthroscopic findings of the menisci in 63 consecutive patients were retrospectively reviewed separately by imaging planes and sequences used, by the site of tear, and by the site of meniscus (medial or lateral meniscus). The number and percentage of false-negative results were recorded. We found that with non fat-suppressed MR techniques, missed tear (false negative reading) of both menisci occurred predominantly in the meniscal body. The prevalence depends on imaging plane and sequence used. Among the techniques reviewed, sagittal T2-weighted (T2W) sequence had the highest prevalence of undetected meniscal tear.

Degenerative disk disease at lumbosacral junction: plain film findings and related MRI abnormalities.

Due to a wide range of normal disk space heights at lumbosacral (LS) junction, we conducted this study to evaluate how to diagnose degenerative disk disease (DDD) of LS junction and how much information we can obtain from plain radiography regarding this condition. We retrospectively reviewed lateral LS spine films and magnetic resonance (MR) imaging in 100 patients presented with low back pain. Anterior disk height (ADH) and posterior disk height (PDH) were directly measured from plain radiographs. Signs of DDD were recorded from both plain radiographs and MR imaging. We found that ADH < 11.3 mm or PDH < 5.5 mm indicate DDD at LS junction with 95 per cent confidence interval. When spondylolisthesis presented, disks were all degenerated. Endplate sclerosis had significant relative risk (p < 0.05) for lateral neural canal stenosis and disk herniation. No radiographic finding showed significant relative risk for nerve root compression.

The patellar tilt angle: correlation of MRI evaluation with anterior knee pain.

The purpose of this study was to analyze the degree of patella tilt and its correlation with the symptoms of anterior knee pain. We used magnetic resonance imaging (MRI) to measure the angle of patella tilt. The patients (n = 128) were classified into two groups. Group 1 (n = 78) included patients who had never had symptoms of anterior knee pain but had MRI for evaluation of the menisci and the ligaments. Group 2 (n = 50) included patients who had MRI for evaluation of anterior knee pain syndrome. Patients who had gross deformities like patellar dislocation, tricompartmental osteoarthritis, or inflammatory arthritis were excluded. The average patella tilt angle was 6.3 (SD = 3.9) and 12.8 (SD = 8.4) degrees, respectively, for the two groups of patients. Twenty-three patients in group 2 underwent arthroscopy because of failure of conservative treatment, and the average patella tilt angle in this subgroup was 16.4 degrees. Our study suggests that patella tilt angle is correlated with the symptoms of anterior knee pain, and indicated that the cause of pain came from the tight lateral retinaculum. In addition, MRI was found to be an accurate and reproducible method of measurement of the patellar tilt angle.