Chronic-Contained Rupture of an Isolated Internal Iliac Arterial Aneurysm: A Case Report

We describe here a 57-year-old woman with a chronic-contained rupture of an internal iliac arterial aneurysm, and this was eroding the sacral neural foramen. Although an isolated internal iliac arterial aneurysm is known to be rare, the ruptured internal iliac arterial aneurysm was diagnosed based on the characteristic radiolgic findings with performing color Doppler ultrasound, MRI and multi-slice computed tomography. The ruptured aneurysm was successfully treated by coil embolization. Color Doppler US, MRI and multi-slice CT are useful for evaluating a mass of a vascular origin that involves the neural foramen.

Relationship of the Area Measurement of the Large Endolymphatic Duct and Sac Syndrome as well as the Clinical Symptoms with CT and MR Imaging Results

PURPOSE: To evaluate the CT and MRI findings of the large endolymphatic duct or sac syndrome (LEDS) and its associated anomalies, with clinical features. MATERIALS AND METHODS: We retrospectively reviewed the MR and CT images of 52 ears obtained from 26 patients with LEDS. We reviewed the clinical findings, audiology testing, and treatment results. The degree of hearing loss was classified from normal to profound, based on pure tone audiometry. The largest areas were measured at each endolymphatic duct and analyzed to determine whether a correlation exists with the degree of hearing loss. We also analyzed the differences in measurements between CT and MRI findings. RESULTS: All 26 patients had some degree of sensorineural hearing loss, which resulted in 18 ears to undergo a cochlear implantation. One patient was diagnosed with Cornelia de Lange syndrome. Five patients had a sudden hearing loss onset. Ten ears had incomplete cochlear partitions, whereas 28 ears had enlarged vestibules. All patients had severe to profound hearing loss. We found no statistical correlation between the size of the largest area of the endolymphatic duct and the degree of hearing loss. The mean area of the endolymphatic ducts, as per an MRI examination, revealed slightly greater areas than the CT findings, although the differences were not significant. CONCLUSION: Enlarged vestibules and incomplete partitions of the cochlea were common anomalies associated with LEDS. We found no statistical correlation between the largest area of the endolymphatic duct or sac with the degree of hearing loss.

Usefulness of Spinal MR Angiography for Detecting Adamkiewicz Artery

PURPOSE: We wanted to evaluate the detection rate of the artery of Adamkiewicz (AKA) by contrast-enhanced MR angiography (CE-MRA) and to compare the detection rate of AKA between the coronal source image plane and the sagittal source image plane. MATERIALS AND METHODS: Between December 2004 and May 2005, 23 patients (9 men and 14 women. age range: 11-86 years, mean age: 43 years) who were examined by contrast-enhanced MRI for the purpose of evaluating spondylopathy were also studied by performing spinal CE-MRA. Spinal CE-MRA was performed with a 1.5-T system and with using 3D Fast field echo with a double dose (0.2 mmol/kg) of Gadolinium. Source images were obtained in either the sagittal plane (n = 11) or the coronal plane (n = 12) at random. The source images were reconstructed with multiplanar reconstruction and maximum intensity projection. Two radiologists, who were kept unaware of the source image plane, independently evaluated the CE-MRA with focusing on the AKA. The detection rate was evaluated and the difference of detection rates according to the source image plane was compared and analyzed. RESULTS: CE-MRA could demonstrate the AKA in 11 (47%) of the 23 patients. The interobserver agreement for detection was fair (κ=0.283). Among the 11 patients in whom the MRA was obtained with using the coronal plane source image, CE-MRA detected the AKA in three of them (27%); among the 12 patients in whom the CE-MRA was obtained with using the sagittal plane source image, CE-MRA detected the AKA in 8 of them (67%, p = 0.059). The AKA in 7 cases (63%) originated from the intercostal or lumbar arteries on the left side at L2 (n = 3), L1 (n = 2), T12 (n = 1) or T9 (n = 1), and on the right side at L1 (n = 1) or T12 (n = 3). CE-MRA with coronal slice orientation visualized the AKA in 8 (67%) of the 11 patients (p = 0.059). CONCLUSION: The detection rate of AKA by CE-MRA was 47%. By obtaining the source image in the coronal plane, the detection rate of AKA was 67%.

Usefulness of Spinal MR Angiography for Detecting Adamkiewicz Artery

PURPOSE: We wanted to evaluate the detection rate of the artery of Adamkiewicz (AKA) by contrast-enhanced MR angiography (CE-MRA) and to compare the detection rate of AKA between the coronal source image plane and the sagittal source image plane. MATERIALS AND METHODS: Between December 2004 and May 2005, 23 patients (9 men and 14 women. age range: 11-86 years, mean age: 43 years) who were examined by contrast-enhanced MRI for the purpose of evaluating spondylopathy were also studied by performing spinal CE-MRA. Spinal CE-MRA was performed with a 1.5-T system and with using 3D Fast field echo with a double dose (0.2 mmol/kg) of Gadolinium. Source images were obtained in either the sagittal plane (n = 11) or the coronal plane (n = 12) at random. The source images were reconstructed with multiplanar reconstruction and maximum intensity projection. Two radiologists, who were kept unaware of the source image plane, independently evaluated the CE-MRA with focusing on the AKA. The detection rate was evaluated and the difference of detection rates according to the source image plane was compared and analyzed. RESULTS: CE-MRA could demonstrate the AKA in 11 (47%) of the 23 patients. The interobserver agreement for detection was fair (κ=0.283). Among the 11 patients in whom the MRA was obtained with using the coronal plane source image, CE-MRA detected the AKA in three of them (27%); among the 12 patients in whom the CE-MRA was obtained with using the sagittal plane source image, CE-MRA detected the AKA in 8 of them (67%, p = 0.059). The AKA in 7 cases (63%) originated from the intercostal or lumbar arteries on the left side at L2 (n = 3), L1 (n = 2), T12 (n = 1) or T9 (n = 1), and on the right side at L1 (n = 1) or T12 (n = 3). CE-MRA with coronal slice orientation visualized the AKA in 8 (67%) of the 11 patients (p = 0.059). CONCLUSION: The detection rate of AKA by CE-MRA was 47%. By obtaining the source image in the coronal plane, the detection rate of AKA was 67%.

Anisotropy Measurement and Fiber Tracking of the White Matter by Using Diffusion Tensor MR Imaging: Influence of the Number of Diffusion-Sensitizing Gradient Direction

PURPOSE: Recent development of diffusion tensor imaging enables the evaluation of the microstructural characteristics of the brain white matter. However, optimal imaging parameters for diffusion tensor imaging, particularly concerning the number of diffusion gradient direction, have not been studied thoroughly yet. The purpose of this study was to evaluate the influence of the number of diffusion gradient direction on the fiber tracking of the white matter. MATERIALS AND METHODS: 13 healthy volunteers (ten men and three women, mean age 30 years, age range 23-37 years) were included in this study. Diffusion tensor imaging was performed with different numbers of diffusion gradient direction as 6, 15, and 32, keeping the other imaging parameters constant. The imaging field ranged from 1 cm below the pons to 2-3 cm above the lateral ventricle, parallel to the anterior commissure-posterior commissure line. FA (fractional anisotropy) maps were created via image post-processing, and then FA and its standard deviation were calculated in the genu and the splenium of the corpus callosum on each of FA maps. Fiber tracking of the corticospinal tract in the brain was performed and the number of the reconstructed fibers of the tract was measured. FA, standard deviation of FA and the number of the reconstructed fibers were compared statistically between the different diffusion gradient directions. RESULTS: FA is not statistically significantly different between the different diffusion gradient directions. By increasing the number of diffusion gradient direction, standard deviation of FA decreased significantly, and the number of the reconstructed fibers increased significantly. CONCLUSION: The higher number of diffusion gradient direction provided better quality of fiber tracking.

MR Findings of Transient Synovitis of the Hip

PURPOSE: To evaluate the MR findings of transient synovitis of the hip in children. MATERIALS AND METHODS: Between 1993 and 1997, MR imaging was performed in 30 children(male:female=22:8) in whom transient synovitis had been clinically diagnosed. In 20 of these 30 patients, Gd-en-hanced study was also performed. The signal intensity of bone marrow of the femur, the synovial enhancement pattern and the amount of hip joint effusion in affected hips were evaluated; the last-mentioned was determined using the volume measurement method. RESULTS: In 29 patients(97 %), no abnormal signal intensity was seen in bone marrow of the femur in affected hips. Gd-enhanced MR imaging revealed synovial enhancement of affected hip joints, as follows: minimal en-hancement in eight patients(40 %), moderate enhancement in eight(40 %), and strong enhancement in four( 20%). No abnormal enhancement was demonstrated in bone marrow of the femur or adjacent soft tissue. The mean amount of joint effusion of affected hips was 2.7 +/- 1.7(range, 0.2 -18.9)ml; statistically, this was much greater than that of contralateral hip (p<0.01). CONCLUSION: The MR findings of transient synovitis of the hip in children were normal bone marrow signal intensity of the femoral head, moderate or strong synovial enhancement, and asymmetric hip joint effusion.