MR Patterns of Bone Marrow of Calvarium and Vertebral Body in Normal Subjects; Pattern Analysis According to Age Distribution

PURPOSE: The purpose of this study is to illustrate MR patterns of bone marrow of calvarium and vertebral body in normal subjects according the age distribution and to understand the course of the fatty replacement from red marrow. METHODS AND MATERIAL: We retrospectively evaluated MR examinations of the calvaria(n=71), cervical spine(n=71), thoracic spine(n=65), Imbar spine(n =68) in subjects without bone marrow abnormality whose age ranged 3 weeks to 74 years. Three distinctive patterns were categorized on Tl-weighted images of the skull. In pattern 1, uniformly low signal intensity with or without very small areas of high intensity in frontal and occipital bones is noted. In pattern 2, frontal and occipital bones have uniformly high signal intensity, and patchy area of high intensity appears in parietal bone. In pattern 3, the entire skull has uniformly high signal intensity. In the spine, four patterns were categorized on Tl-weighted MR images. In pattern 1, the vertebral body has uniformly low signal intensity except for linear areas of high intensity superior and inferior to basivertebral vein. In pattern 2, bandlike and triangular areas of high signal intensity are found in the periphery. Pattern 3 and 4 have diffusely distributed areas of high signal intensity; pattern 3 consist of numerous indistinct dots measuring a few millimeter or less, and pattern 4 consist of fairly well marginated areas ranging in size from 5 to 1.5cm. RESULT:In the calvaria, 73% of pattern 1 were younger than 20 years, pattern 2 were evenly distributed, and 86% of pattern 3 were older than 40 years. In the spine, 87% of pattern 1 were younger than 40 years, 72% of pattern 3 were in 40 to 50 years, and 87% of pattern 4 were older than 50 years. Pattern 2 were evenly distributed in the cervical and thoracic spine, but in the thoracic spine 62% were younger than 30 years. CONCLUSION:It is concluded that younger age group shows mainly pattern 1, whereas elderly group has pattern 3 or 4 in the calvarial and vertebral body marrow. This suggests that conversion to fatty marrow begin locally and progress diffusely with age.

Radiologic Reevaluation of the Ampulla of Vater Cancer

Objective: To evaluate the radiographic characteristics of the ampulla of Vater cancer. Subjects and Methods:The authors analyzed retrospectively the US(n=25) and CT(n=15) findings in 25 cases of ampulla of Vater cancer, with emphasis on the potential of CT & US in regand to the detectibility of the mass. ERCP(n=15) and hypotonic duodenography(n=5) were also evaluated for the configuration of obstructed duct. RESULTS: The tumor was detected on sonography in only 12 cases(48%) as a small, relatively well delinated mass with slighty low echogenicity to the pancreas. The tumor was shown by CT in 8 cases(53% ) as a well delinated mass protruding into the second portion of duodenal lumen with slightly low attenuation to the pancreas. CBD was dilated in 25 cases(100%), but pancreatic duct was dilated in 15 cases(60%). Obstructed end of CBD was nipple shaped in 7 cases(47%), clubbed in 3, flat in 3, and indistict in 2 by ERCP. Hypotonic duodenogram showed irregular filling defect in the medial wall of second portion of the duodenum in 5 cases (100%). CONCLUSION: Mas detection rate crsing US or CT were not high in ampulla of Vater cancer. Except for a CT finding of a small mass protruding into the regional duodenal lumen, other finclings were nonspecific. Therefore, additional studies or more afgressive approach should be attempted for a correct diagnosis.

CT and Fluoroscopy Guided Celiac Ganglion Block

PURPOSE: To evaluate the effects and usefulness of fiuroscopy guided celiac ganglion block after marking of needle path with CT scan. MATERIALS AND METHODS: Celiac ganglion block with 100% ethyl alcohol was performed in 50 cancer patients who were inoperable and had intractable abdominal pain. Duration and degree of pain relief after the procedure and its complication were analyzed. RESULTS: Early pain relief was observed in 98% and long term relief in 68% without serious complication. CONCLUSION: Fluoroscopy guided celiac ganglion block after marking of needle path with CT scan was a safe and valuable procedure in relieving intractable pain in terminal cancer patients and reduced the time in the CT room.

MR appearances of intracranial tumors with a low tesla (0.064 T) permanent MR system

In this report we describe twenty-two cases of intracranial tumors studied with an MR imager operating at a field strength of 0.064 T for evaluation of the clinical utility of low tesla MRI. The comfirmed diagnoses were meningioma(9 cases), astrocytoma(4 cases), glioblastoma multiforme(1 case), craniopharyngioma(2 cases), intracranial metastasis(1 case). pituitary microadenoma (1 case), hemangioblastoma (1 case), and trigerminal neurilemmoma(1 case). Meningiomas appeared as well-marginated, homogenous signal intensity masses(67%) in most cases. Most meningiomas showed iso-signal intensity(78%) on T1-weighted images, and high signal intensity on T2-weighted images. After Gd-DTPA enhancement, diffuse homogeneous contrast enhancement(75%) was well see. The multiple hemorrhagic foci within the glioblastoma multiforme were identified, which shoed high signal intensity on T1-weighted images and low signal intensity on T2-weighted images(intracellular methemoglobin), or high signal intensity on both T1 and T2-weighted images(extracellular methemoglobin). One case of cerebellar hemangioblastoma was a well-defined cystic mass with contrast enhanced mural nodule but no identification of characteristic signal void vessels. The remianing tumors showed low signal intensity on T1-weighted images, and high signal intensity on T2-weighted images. Gd-DTPA enhancement was helpful in separating the lesion from the surrounding edema or normal tissue, but had limited diagnostic value in characterizing the nature of the mass. The advantages of low tesla MRI are as follows on requirement of cooling water or electricity, open design, shorter T1 relaxation time compared with high tesla unit that increases the difference of T1-relaxation time between tissues, ease of installation, and cost effectiveness. In conclusion, the low tesla MRI is useful for the detection and evaluation of the brain tumors.