E-Book, Englisch, 256 Seiten, ePub
Möller / Moeller / Reif Normal Findings in CT and MRI
1. Auflage 1999
ISBN: 978-3-13-258089-3
Verlag: Thieme
Format: EPUB
Kopierschutz: 6 - ePub Watermark
E-Book, Englisch, 256 Seiten, ePub
ISBN: 978-3-13-258089-3
Verlag: Thieme
Format: EPUB
Kopierschutz: 6 - ePub Watermark
The key for any beginning radiologist who wishes to recognize pathological findings is to first acquire an ability to distinguish them from normal ones. This outstanding guide gives beginning radiologists the tools they need to systematically approach and recognize normal MR and CT images.
Highlights include:
- Reference-quality images from the author's own teaching files show all standard normal findings as seen in CT and MRI - Checklists in each section offer the reader a systematic way to approach the images - Thorough guidelines to help beginning radiologists dictate their reports - Lists of standard measurements and tips for ruling out pathology
Zielgruppe
Ärzte
Autoren/Hrsg.
Fachgebiete
Weitere Infos & Material
Computer Tomography CT: Head and Neck CT: Chest CT: Abdomen CT: Spinal Column Magnetic Resonance Imaging MRI: Head and Neck MRI: Chest MRI: Abdomen MRI: Spinal Column MRI: Joints MRI: Special Investigations
CT: Abdomen Upper Abdominal Organs The liver is normally positioned and has normal size and smooth borders. Its internal structure and attenuation values are normal. The intrahepatic and extrahepatic bile ducts and gallbladder are unremarkable. The spleen is orthotopic and of normal size. It has smooth outer contours and a homogeneous internal structure. The pancreas is normal in size, position, and internal structure with smooth, lobulated outer contours. The pancreatic duct is unobstructed. Both kidneys show normal size and position. The renal parenchyma shows normal width and structure. The renal pelvis and calices show a normal configuration. The urinary drainage tract is unobstructed. The adrenal glands are unremarkable. Major blood vessels appear normal, and there is no evidence of lymphadenopathy. Imaged portions of the lung and soft tissues are normal. Interpretation The upper abdominal organs appear normal at CT. Checklist Liver • Position – Directly below the right hemidiaphragm • Size (see below) • Borders: – Smooth – Sharp • Normal attenuation values (see below) • Homogeneous internal parenchymal structure • No focal abnormalities • Intrahepatic bile ducts: – Course (centrifugal) – Width (general rule: ducts should no longer be visible after contrast administration—see below) – No calculi – No air • Extrahepatic bile ducts: – Course (from porta hepatis to head of pancreas) – Width (see below) – Contents of homogeneous fluid density – No calculi – No air • Gallbladder: – Size (see below) – Smooth outer contours – Normal wall thickness (see below) – No pericholecystic fluid • Gallbladder contents: – Homogeneous – Fluid density – No calculi (hypodense or hyperdense) – No air • Porta hepatis occupied by the hepatic artery, common bile duct, and portal vein • No masses • No lymphadenopathy • Costophrenic sinus clear and aerated on both sides Spleen • Size (see below) • Smooth outer contours • Homogeneous internal structure • Attenuation values (see below) Pancreas • Size normal for age (see below) • Normal lobulation • Smooth outer contours • Pancreatic duct unobstructed • No peripancreatic fluid • Normal para-aortic region Kidneys • Paired • Position (see below) • Size (see below) • Smooth contours • Width of parenchyma (see below) • Density (see below) • Width of cortex and medulla • Renal pelvis (anatomy, symmetry, size, no widening, contents of homogeneous fluid density) • Calices (shape, width, homogeneous contents) • Enhancement characteristics (see below) Ureters • Not duplicated • Course • No obstruction of urinary drainage • Normal-appearing periureteral fat • Near-simultaneous opacification of both ureters after contrast administration Adrenal glands • Shape • Size (see below) • Slender crura • No circumscribed hypodense (cyst, adenoma), isodense or hyperdense expansion Intestinal structures (colon haustrations, small bowel) • Anatomy • Shape • Wall thickness • Homogeneous opacification after oral contrast administration • No free extraintestinal or intra-abdominal air or fluid Major vessels • Position • Size (see below) • Luminal opacification after contrast administration • No large (intimal) calcifications • No mural thrombosis • No dissection Lymph node stations (especially retrocrural, mesenteric, paraaortic) • No lymphadenopathy Lung segments • Configuration • Complete aeration • No adhesions • No pulmonary nodules Soft tissues • Anatomy • Symmetry • Density Important Data Dimensions: 1 Liver: a Angle of left hepatic border: ca. 45° b Left lobe (anteroposterior diameter measured on the paravertebral line): up to 5 cm • Caudate lobe/right lobe (CL/RL) = 0.37 ± 0.16 (e.g., 0.88 ± 0.2 incirrhosis) 2 Spleen: a Depth (D): 4–6 cm b Width (W): 7–10 cm c Length (L): 11–15 cm (reconstruction) Splenic index: D × W × L = between 160 and 440 3 Pancreas: a Head up to 3.5 cm b Body up to 2.5 cm c Tail up to 2.5 cm 4 Adrenal glands (variable): • Crural thickness < 10 mm 5 Gallbladder: a Horizontal diameter up to 5 cm (> 5 cm is suspicious for hydrops) b Width of gallbladder wall: • 1–3 mm c Width of common bile duct: • = 8 mm (after cholecystectomy: = 10 mm) 6 Inferior vena cava: • Transverse diameter up to 2.5 cm 7 Abdominal aorta: • Transverse diameter ca. 18–30 mm 8 Kidneys: a Anteroposterior diameter ca. 4 cm b Transverse diameter 5–6 cm; craniocaudal diameter (= highest to lowest section) 8–13 cm c Transverse renal axis: posteriorly divergent angle of 120° d Width of renal cortex: 4–5 mm e Width of ureter: 4–7 mm Position of superior poles of kidneys: • Right: superior border of L1 • Left: inferior border of T12 Time to corticomedullary equilibrium: • 1 minute Contrast excretion into the pyelocaliceal system: • 3 minutes Gerota fascia (thickness): • 1–2 mm Lymph nodes larger than 1 cm are suspicious for pathology. Attenuation values: • Liver: 65 ± 10 HU • Spleen: 45 ± 5 HU • Pancreas: 40 ± 10 HU • Fat: -65 to -100 HU • Kidneys: 30–45 HU without contrast medium; renal cortex after contrast medium: approx. 140 HU • Adrenal glands: 25–40 HU without contrast medium • Muscle: 45 ± 5 HU • Blood vessels: approx. 40–55 HU without contrast medium • Gallbladder contents: 0–25 HU Liver The liver is orthotopic and of normal size, with smooth borders and normal attenuation values. It presents a normal internal structure with no focal abnormalities. The intrahepatic and extrahepatic bile ducts are normal in their course, width, and contents. The gallbladder appears normal, presenting smooth borders and homogeneous contents. The porta hepatis shows no abnormalities. Other visualized upper abdominal organs are unremarkable. Interpretation The liver appears normal at CT. Checklist Liver • Position: – Directly below the right hemidiaphragm • Size (see below) • Borders: – Smooth – Sharp • Attenuation values (see below) • Homogeneous internal parenchymal structure, no focal abnormalities • Intrahepatic bile ducts: – Course (centrifugal) – Width (general rule: ducts should no longer be visible after contrast administration) – No calculi – No air • Extrahepatic bile ducts: – Course (from porta hepatis to head of pancreas) – Width (see below) – Contents of homogeneous fluid density – No calculi – No air • Gallbladder: – Size (see below) – Contours (smooth and sharp) – Wall thickness (see below; no general or circumscribed thickening) – No pericholecystic fluid • Gallbladder contents: – Homogeneous – Fluid density (see below) – No calculi (hypodense or hyperdense) – No air – Porta hepatis occupied...
