CT Anatomy of the Abdomen and Pelvis - Human Health ...
-
Upload
khangminh22 -
Category
Documents
-
view
0 -
download
0
Transcript of CT Anatomy of the Abdomen and Pelvis - Human Health ...
CT Anatomy of the Abdomen and Pelvis
J. Antonio Obando, MDYale university School of MedicineVA Connecticut Healthcare System
Objectives
• Review crossectional imaging of peritoneal and retroperitoneal spaces
• Review anatomy of the lymph nodes • Anatomy of intra abdominal organs
Peritoneum
• Serosal membrane• Encases the peritoneal cavity • Composes the mesenteries,• Partially or completely covers the abdominal and pelvic viscera.
Anatomic peritoneal spaces
• Peritoneal cavity: potential space between visceral and parietal peritoneum
• Visceral peritoneum lines:– Intraperitoneal organs– Mesenteries and omenta
Anatomic peritoneal spaces
Parietal peritoneum lines:• undersurface of the hemidiaphragm• abdominal wall• anterior surface the retroperitoneum• pelvis
Peritoneal ligaments
• Double folds of peritoneum. • Suspend and support the intraperitonealorgans
• Subdivide the peritoneal cavity into interconnected compartments
• Dictate the flow of fluid and location of disease
Peritoneal ligaments
• Coronary • Gastrohepatic• Hepatoduodenal• Falciform• Gastrocolic• Duodenocolic• Gastrosplenic
Peritoneal fluid
Areas of stasis• Ileocolic region • Root of the sigmoid mesentery • Pouch of Douglas
Pathologic processes of the peritoneum
• Metastatic neoplasms• Infectious and inflammatory lesions• Miscellaneous tumors and tumor‐like lesions
Pathologic processes of the peritoneum
• Metastatic neoplasms• Carcinomatosis• Pseudomyxoma peritoneiInfectious and inflammatory lesions
• Granulomatous peritonitis• Inflammatory pseudotumor• Sclerosing encapsulating peritonitis• Endometriosis• Splenosis
Cirrhosis
• Hepatocytesdestruction
• Inflamatory response• Nodularity• Fibrosis• Portal hypertension
Liver tumor enhancement
• Liver blood supply: 80% portal vein
– 20% hepatic artery
• Tumors 100% supply from hepatic artery– Enhance in arterial phase
Contrast phases
• Early arterial phase. FNH
• Portal venous phase. Hypovascular met
• Equilibriumcholangiocarcinoma
Arterial phase imaging
• Characterisaton of a liver lesion of unknown origin
• Detection of HCC in patients with a high alpha 1 fetoprotein
• Screening of cirrhotic patients for HCC.• Detection of metastases in patients with hypervascular tumors
SMA thrombosis
•lack of enhancement of the lumen of the SMA•bowel wall thickening•ileus•absent mucosal enhancement•free fluid•mural gas, portal venous gas
Lymph nodes
• Diameter: 1cm• Porta hepatis: 6 mm• Retrocrural : 6 mm• Multiple: > 8 to 10 mm suspicious• False positives: hepatitis
Lymph nodes
• Paraaortic• Inferior mesenteric• Common iliac• Internal iliac• External iliac• Superficial inguinal• Deep inguinal• Sacral• Pararectal
Abdomen CT Questions
J. Antonio Obando, MDYale University School of MedicineVA Connecticut Healthcare System
CT Abdomen Question 1
• Hypodense lesion in the liver, seen on CT
• 1) Segment 2• 2) Segment 7• 3) Caudate lobe• 4) Segment 8• 5) Segment 6
CT Abdomen Answers Question 1• 1) Segment 2. Segment 2 is
in the left lobe• 2) Segment 7. Is the
posterior and superior segment
• 3) Caudate lobe. Is medial, and anterior to vena cava
• 4) Segment 8. Anterior to the left hepatic vein
• 5) Segment 6. Posterior and inferior segment liver segment.
CT Abdomen Question 2
38 y.o. female with abdominal pain. Location of the abnormality:
• 1)Intraperitoneal• 2) Left Perirenal space• 3) Left pararenal space• 4) Left paravertebral region
CT Abdomen Answer Question 2
• 1)Intraperitoneal. The bleeding is retroperitoneal
• 2) Left Perirenal space.• 3) Left posterior pararenal space
• 4) Left paravertebral region.
CT Abdomen Question 3
• 72 y.o. male with hematuria. The abnormality in the right kidney is:
• 1) Simple cyst• 2) Infarct• 3) Hypervascular lesion• 4)Scar• 5) Normal variant
CT Abdomen Answer Question 3
• 1) Simple cyst. Simple cysts do not enhance• 2) Infarct. Renal infarcts are usually wedge shaped and do not enhance
• 3) Hypervascular lesion. Biopsy showed RCC• 4)Scar. Scars do not enhance• 5) Normal variant. Post contrast scan is definitely abnormal
CT Abdomen Question 4
• Hypodensity shown in the CT is located:
• 1) Segment 2• 2) Segment 3• 3) Caudate lobe• 4) Segment 4A
CT Abdomen Answers Question 4
• Hypodensity shown in the CT is located:
• 1) Segment 2• 2) Segment 3• 3) Caudate lobe• 4) Segment 4A
CT Abdomen Question 582 y.o. male with severe abdominal pain. CT image shows:
• 1) Left retroperitoneal hematoma
• 2) Ruptured AAA with retroperitoneal hematoma
• 3) Right retroperitoneal mass
• 4) Right retroperitoneal lymphadenpathy
CT Abdomen Question 5
• 1) Left retroperitoneal hematoma
• 2) Ruptured AAA with retroperitoneal hematoma
• 3) Right retroperitoneal mass
• 4) Right retroperitoneal lymphadenpathy
CT Abdomen Question 6
• 57 y.o. male history of ETOH abuse, abdominal pain.
• Diagnosis:• 1) Ascitis• 2) Pancreatitis• 3) Cirrhosis• 4) Pancreatic necrosis