ABSTRACT
Vertebral artery dissection is the first diagnosis that must be suspected by a 40 years old patient with posterior fossa ischemic signs. CT data from six cases of spontaneous or post-traumatic vertebral artery dissections are reviewed. Cervical CT is performed after contrast medium injection from C7 to C0 with 1.5 mm thick slices and a 2 mm gap or with a spiral mod including millimetric reconstruction. The enhancement of the vascular wall, the hypodense hematoma surrounding a stenotic and eccentric lumen, and the enlargement of the artery are typical for a vertebral artery dissection. CT findings were correlated with angiography that is still considered to be the gold standard for this diagnosis. Among noninvasive technics including MRI, duplex scanning and CT, the latter appears very accurate to diagnose vertebral artery dissection.
Subject(s)
Aortic Dissection/diagnostic imaging , Neck/diagnostic imaging , Tomography, X-Ray Computed/methods , Vertebral Artery , Adult , Aortic Dissection/diagnosis , Angiography , Female , Humans , Magnetic Resonance Imaging , Male , Middle AgedABSTRACT
OBJECTIVE: We propose a simple, compact, and accurate light guidance system for interventional CT. MATERIALS AND METHODS: The system using intersecting laser beams is mounted on the CT gantry and ensures precise needle guidance even when the gantry is tilted. The device does not require additional software/hardware. RESULTS: Phantom simulations and clinical experiments have demonstrated an accuracy of +/- 1 degrees and +/- 1 mm. CONCLUSION: The laser guidance system for CT makes the intervention safer, faster, and more accurate.
Subject(s)
Lasers , Radiography, Interventional/methods , Tomography, X-Ray Computed/methods , Biopsy, Needle/instrumentation , Biopsy, Needle/methods , Equipment Design , Humans , Models, Structural , Radiography, Interventional/instrumentation , Tomography, X-Ray Computed/instrumentationABSTRACT
OBJECTIVE: We studied the ability of MRI to predict fetal shoulder width (FSW). MATERIALS AND METHODS: In 30 patients referred for MR pelvimetry, measurement of FSW was performed and compared with caliper measurements at term. We report here the feasibility of a method using axial and coronal MR images oriented to the fetal body axes. RESULTS: Shoulder width by MRI (mean = 12.76 +/- 1.42 cm) correlated significantly with postnatal orthopedic caliper measurements (mean = 12.99 +/- 1.37 cm; r = 0.955, SEE = 4.29 mm, p = 0.00001) and with birth weight (r = 0.63, p = 0.0005). Mean paired differences showed a statistically significant 2.3 +/- 4.2 mm underestimation of FSW by MRI (p = 0.01). This reasonably quick nonionizing technique seems to have the potential for evaluating shoulder dystocia and deserves further evaluation.
