PURPOSE: As a baseline study for clinical application, we investigated MRI findings of normal cruciate ligaments in the knee being flexed as compared to those in the knee being extended. MATERIALS AND METHODS: Seven asymptomatic volunteers were studied. Knee MRI was performed with a 1.5 Tesla unit using a dual 3 inch coil. Inthe decubitus position, sagittal scanning was performed with the knee in extension, and subsequently, in flexion. We observed the shape and signal intensity of both cruciate ligaments, and measured the angles between the longaxis of the femur and ligaments, and the ligament dimensions in extension and flexion images. RESULTS: As flexionand extension images were compared, cruciate ligaments differed both in their appearance and dimensions. With flexion, joint space was widened, PCL became straightened and the signal intensity of ACL became homogeneously low; both cruciate ligaments became longer and thinner. These MRI findings were statistically significant except forthinning of PCL. CONCLUSION: MRI appearance and the dimensions of cruciate ligaments were different in the flexed knee as compared to those in the extended knee.
Femur ; Joints ; Knee* ; Ligaments* ; Magnetic Resonance Imaging* ; Volunteers

OBJECTIVE: The authors investigated the clinical and radiographic characteristics of patients who exhibited contrast extravasation on initial computed tomographic angiography (CTA) and assessed the its association with hematoma expansion. METHODS: Ninety six patients who were diagnosed with intracerebral hemorrhage and who received CTA within 12 hours from initial onset of symptoms and who received a follow up brain CT within 48 hours from the initial CTA between April 2004 and March 2007 were retrospectively assessed. Contrast extravasation was defined as the presence of high-density material within the hematoma. Patients were classified into the extravasation and no extravasation groups. Clinical and radiographic variables were compared between the two groups. RESULTS: Fifteen patients (19%) demonstrated presence of extravasation on initial CTA. A significantly higher rate of hematoma expansion was seen in the extravasation group compared to the non extravasation group (47% vs 17%, p=0.027). Mean time from onset of symptoms to initial CTA was significantly shorter in the extravasation group (3.5+/-1.3 hours vs 7.6+/-2.5 hours, p<0.001). Also, detection of extravasation on CTA significantly correlated with time from symptom onset to intial CTA, especially when it was less than 4 hours (p>0.001). CONCLUSIONS: Earlier detection of extravasation using CTA may help in identifying possibly life threatening complications caused by hematoma expansion. However, a larger prospective cohort is warranted to validate this result.
Angiography* ; Brain ; Cerebral Hemorrhage* ; Cohort Studies ; Follow-Up Studies ; Hematoma ; Humans ; Retrospective Studies