Signal Void Dots on T2-weighted Brain MR Image: Correlation with Hypertensive Brain lesions

PURPOSE: To evaluate the relationship of signal void dots seen on T2-weighted images with hypertension,hypertensive intracerebral hemorrhage and infarction. MATERIALS AND METHODS: MR images of 73 consecutive patientswith signal void dots on T2-weighted images were reviewed. Seventy-three randomly selected age-matched patientswithout signal void dot lesion were also reviewed. We evaluated 1) the location and number of signal void dots; 2)the frequency of hypertension among patients and controls; 3) the frequency of associated brain parenchymalabnormalities (hypertensive intracerebral hemorrhage, microangiopathy and infarction) in both groups; 4) therelationship between the number of signal void dots and associated brain lesions in the patient group. RESULTS: Signal void dots numbered 1-50(average, 12), and were found mostly in the thalamus, basal ganglia, and the pons.Hypertension(97.1%), hypertensive ICH(43.8%) and microangiopathy(96%) were frequent in patients with signal voiddots, the number of which correlated with the severity of microangiopathy. Infarction(13.7%), however, did notcorrelate with dots. CONCLUSION: Signal void dots correlate closely with hypertension, hypertensive ICH, andmicroangiopathy. They may indicate hypertensive brain change.

Brain MR Imagings Finding in Patients with Central Vertigo

PURPOSE: To investigate brain lesions and their locations in patients with central vertigo, as seen on MRimaging. MATERIALS AND METHODS: We retrospectively reviewed MR images of 85 patients with central type vertigodiagnosed on the basis of clinical symptoms and vestibular function test (VFT), and analyzed lesions and theirlocations. Those located along the known central vestibular pathway were included in our study. RESULTS: In 29 of85 patients (34%), lesions considered to be associated with central vertigo were detected on MR imaging. Theseincluded infarction (18 patients), hemorrhage (5), tumor (2), cavernous angioma(1), cerebellopontine anglecyst(1), tuberous sclerosis(1) and olivopontocerebellar atrophy(1) ; they were located in the parietal lobe(6patients), the lateral medulla(5), the pons(5), the middle cerebellar peduncle(4), the corona radiata(3), and thecerebellar vermis(3). Thirty-eight cases showed high signal intensity lesions in deep cerebral matter, the basalganglia, and pons but these were considered to be unrelated to central vertigo. CONCLUSIONS: MR imaging could bea useful tool for the evaluation of patients with central vertigo.

The Difference in the Appearance of Proximal Humeral Epiphyseal Ossification Center on Chest Radiograph between the preterm and Full-term Infants

PURPOSE: To assess the difference in the appearance of the proximal humeral epiphyseal ossification center, as seen on chest radiograph, between preterm and full-term infants at the same corrected ages. MATERIALS AND METHODS: Forty two preterm infants born at 26-35 weeks of gestational age and 218 normal full-term infants born at 38-42 weeks were investigated. Because of various perinatal problems, the preterm infants were treated at a neonatal intensive care unit. Proximal humeral epiphyseal ossification centers were evaluated from chest radiographs, and in cases of preterm infants, the corected age of 0 month was defined as postconceptional 40 weeks. In preterm infants, the numbers of chest radiographs obtained were 42 at 0 month, 40 at 1 month, 37 at 2 months and 36 at 3 months of corrected age, while in those who were full-term, the numbers were 103 cases at 0 month, 42 at 1 month,42 at 2 months and 31 at 3 months of age. In the preterm group, alkaline phosphatase, calcium, phosphorus levels and simple wrist radiographs were checked. We then evaluated the difference of appearance of the proximal humeral epiphyseal ossification center between preterm and full-term infants at the same corrected ages, as well as the difference between causative diseases, between the normal and abnormal serologic group and between the normal and abnormal wrist group in preterm infants at the same corrected ages. Using Fisher's exact test, the data were analysed. RESULTS: The incidences of the proximal humeral epiphyseal ossification center in preterm infants were 2.4% (1/42) at 0 month, 20.0% (8/40) at 1 month, 43.2% (16/37) at 2 months and 69.4% (25/36) at 3 months; infull-term infants, the figures were 24.3% (25/103) at 0 month, 66.7% (28/42) at 1 month, 83.3% (35/42) at 2 months and 90.3% (28/31) at 3 months. At 0, 1, and 2 months, the incidences were thus seen to be lower in preterm than infull-term infants(p0.05). In preterm infants, there were no statistical differences between causative diseases, between the normal and abnormal serologic group and between the normal and abnormal wrist group(p>0.05). CONCLUSION: Up to the age of two months, the proximal humeral epiphyseal ossification center of preterm infants appears later than that of full-term infants at the same corrected age.