Chapter 25 - Abdomen and Pelvis Flashcards
IDENTIFY THE RADIOGRAPHIC FINDING.
[FIGURE 25.15]
PANCREATIC CALCIFICATIONS
Coarse and punctate calcifications (arrow) extend upward across the left upper quadrant in this patient with chronic alcoholic pancreatitis. Calcifications in the pancreatic head (arrowhead) are obscured by the spine.
DIAGNOSIS ?
IDENTIFY THE RADIOLOGIC SIGN POINTED BY THE ARROWHEAD.
[FIGURE 25.23]
SMALL BOWEL OBSTRUCTION – CT;
SMALL BOWEL FECES SIGN
Coronal plane reconstructed CT demonstrates abrupt transition (arrow) between dilated and nondilated small bowel in this patient with radiation enteritis causing small bowel obstruction.
DIAGNOSIS ?
[FIGURE 25.25]
TRANSIENT INTUSSUSCEPTION
CT in an asymptomatic patient studied for other reasons shows a short-segment enteroenteric intussusception (arrows) without proximal small bowel dilatation.
DIAGNOSIS ?
[FIGURE 25.21]
FOURNIER GANGRENE
CT shows prominent pockets of gas (arrows) in the subcutaneous tissues of the perineum and the scrotum
characteristic of this condition.
DIAGNOSIS ? [FIGURE 25.32]
[FIGURE 25.32]
HODGKIN LYMPHOMA - CT
CT shows bulky confluent adenopathy (arrows) in the retroperitoneum surrounding the aorta (Ao) and displacing the inferior vena cava (IVC) anteriorly. Masses of lymphoma (arrowhead) are also present in the spleen.
IDENTIFY THE RADIOGRAPHIC FINDING.
[FIGURE 25.17]
TUMORAL CALCIFICATIONS
Radiograph of the abdomen demonstrates cloudlike calcifications in the distribution of peritoneal recesses. These calcifications were caused by intraperitoneal spread of
a papillary serous cystadenocarcinomas of the ovary.
ANATOMY OF THE PERITONEAL CAVITY
[FIGURE 25.1]
A. Diagram of an axial cross section of the abdomen illustrates the recesses of the greater peritoneal cavity and the lesser sac.
B. CT scan of a patient with a large amount of ascites nicely demonstrates the recesses of the greater peritoneal cavity and the lesser sac. The lesser sac is bounded by the stomach (St) anteriorly, the pancreas (P) posteriorly, and the gastrosplenic ligament (curved arrow) laterally.
The falciform ligament (arrowhead) separates the right and left subphrenic spaces. Fluid from the greater peritoneal
cavity extends into Morison pouch (arrow) between the liver and the right kidney. Fluid in the gastrohepatic recess (asterisk) separates the stomach from the liver (L). S, spleen; GB, gallbladder; RK, right kidney; IVC, inferior vena cava; Ao, aorta; LK, left kidney.
IDENTIFY THE PROBLEM.
[FIGURE 25.6]
PERINEAL TUMOR
A CT scan of a 12-year-old girl with a history of a rhabdomyosarcoma of the right leg demonstrates a tumor
metastasis (T) in the right ischiorectal fossa. The left ischiorectal fossa (IRF) shows its normal appearance as a triangle of fat bordered by the rectum (R), obturator internus (OI) muscle, and the gluteus muscles (GM).
The ischiorectal fossa is entirely below the levator ani and is
part of the perineum. c, tip of the coccyx; IT, ischial tuberosities.
DIAGNOSIS ?
[FIGURE 25.7}
PSEUDOMYXOMA PERITONEI
A CT scan of a 60-year-old man with intraperitoneal spread of mucinous adenocarcinoma of the colon shows loculations
(arrowheads) of fluid indenting the surface of the liver (L), giving evidence of mass effect. The attenuation of the fluid measured 32 H, indicating exudative ascites.
DIAGNOSIS ? [FIGURE 25.13]
BLADDER CALCULI
Numerous calculi (arrows) in the bladder are evident on this conventional radiograph of the pelvis. The large prostate (P, between arrowheads), responsible for urinary stasis leading to stone formation, makes a mass impression on the layering stones. Also evident are atherosclerotic calcifications in the iliac arteries (curved arrows).
THE LESSER SAC
[FIGURE 25.2]
Sagittal plane diagrams of the medial (A) and lateral (B) aspects of the lesser sac illustrate its position posterior to the stomach and anterior to the posterior parietal peritoneum covering the pancreas.
Note that projections of the lesser sac extend to the diaphragm,
resulting in the potential for disease processes in the lesser sac to cause pleural effusions. The coronary ligaments reflect between the liver and the diaphragm producing a bare area of liver not covered by peritoneum; FLV, fissure of the ligamentum venosum.
DIAGNOSIS ? [FIGURE 25.9]
PNEUMOPERITONEUM:CT
A collection of air (arrow) is seen within the peritoneal space between the liver (L) and the diaphragm (arrowhead). This is a prime area to search to detect small amounts of free intraperitoneal air on CT. This patient had a torn jejunum as a result of trauma from a motor vehicle collision.
DIAGNOSIS ? [FIGURE 25.27]
CECAL VOLVULUS
Supine abdominal radiograph demonstrates
displacement of the dilated cecum (C) to the epigastrium. The
more distal colon is collapsed. The diagnosis was confirmed at surgery.
IDENTIFY THE RADIOGRAPHIC FINDING.
[FIGURE 25.11]
PORCELAIN GALLBLADDER
Cone-down radiograph of the right upper quadrant of the abdomen demonstrates calcification in the wall of the gallbladder (arrow). This finding is indicative of chronic
obstruction of the cystic duct, chronic gallbladder inflammation, and an increased risk of gallbladder carcinoma.
DIAGNOSIS ?
[FIGURE 25.26]
SIGMOID VOLVULUS
Radiograph of the abdomen demonstrates the characteristic massive dilation of the sigmoid colon (S) arising from the pelvis and extending to the left diaphragm. The three lines representing the walls of the twisted loop converging to the left
lower quadrant are evident (1, 2, 3).
NORMAL or ABNORMAL ?
[FIGURE 25.18]
NORMAL BOWEL GAS PATTERN
Supine radiograph shows the normal distribution of gas in the stomach (large arrow) and the duodenum (small arrow).
The normal mottled pattern of stool is seen in the distribution of the right colon (arrowhead). A few gas collections
within small bowel (curved arrow) are seen in the pelvis.
IDENTIFY THE RADIOGRAPHIC FINDING.
[FIGURE 25.19]
SENTINEL LOOP
Daily serial radiographs of this patient demonstrated a persistent loop of dilated small bowel (arrow) in the same location.
This sentinel loop was caused by acute pancreatitis.
Normal gas pattern is present in the right colon (arrowhead). The
abdomen is otherwise devoid of intestinal gas.
IDENTIFY THE RADIOLOGIC FINDING.
[FIGURE 25.20]
TOXIC MEGACOLON
A. Supine radiograph of the abdomen demonstrates marked dilation of the colon with the cecum measuring 14 cm
(red line) and the descending colon measuring 7 cm (white line) in diameter. The mucosal pattern of the lower descending colon is strikingly nodular (arrowhead).
B. Corresponding CT showed marked thickening of the wall of
the colon. Toxic megacolon was related to ulcerative colitis. The colon perforated just prior to surgery.
DIAGNOSIS ? [FIGURE 25.31]
RENAL INFARCTION
Postcontrast CT reveals a lack of enhancement (arrow) of the posterior portion of the left kidney (LK), which occurred as a result of an intimal tear and thrombosis of a branch renal artery occurring during a motor vehicle collision.
Note that the defect in enhancement extends to the capsule of the kidney indicating acute renal vascular injury.
IDENTIFY THE RADIOLOGIC FINDING.
WHAT IS THE MOST LIKELY DIAGNOSIS?
[FIGURE 25.35]
EXTRAMEDULLARY HEMATOPOIESIS;
SICKLE CELL DISEASE
CT without contrast shows a slightly high-attenuation left paraspinal mass (arrow) and a smaller right paraspinal mass (arrowhead). Cardiomegaly is evident.
The patient also had massive hepatosplenomegaly. Extramedullary hematopoesis was induced by sickle cell disease.
IDENTIFY THE RADIOLOGIC FINDING.
[FIGURE 25.28]
PNEUMATOSIS INTESTINALIS
A. Digital radiograph scout scan from CT reveals pneumatosis of the colon as dark linear streaks of air (arrowheads) in the colon wall. Both small and large bowels are markedly dilated.
B. CT image of the same patient viewed with lung windows confirms the presence of air in the colon wall (arrowheads). The small bowel (SB) is dilated. At surgery, both small and large bowels were infracted. The patient expired.
DIAGNOSIS ? [FIGURE 25.22]
SMALL BOWEL OBSTRUCTION – Conventional Radiograph
Erect radiograph of the abdomen reveals dilated air-filled loops of small bowel containing air-fluid levels at different heights within the same loop (arrows).
Note the valvulae conniventes (arrowhead) that extend across the entire diameter of the bowel lumen.
The small bowel obstruction was due to adhesions
DIAGNOSIS ? [FIGURE 25.36]
RETROPERITONEAL FIBROSIS
Coronal plane-reconstructed CT performed without IV contrast shows poorly marginated soft tissue (arrows) encasing the distal aorta and common iliac vessels.
The right ureter was enveloped and obstructed by the fibrosing process.
A ureteral stent (arrowhead) is in place. The left kidney is
absent.
DIAGNOSIS ?
[FIGURE 25.24]
ENTEROENTERIC INTUSSUSCEPTION
CT shows small bowel obstruction with dilated proximal small bowel extending to an area of
jejuno-jejunal intussusception (arrows).
The lead point proved to be a metastatic lesion from malignant melanoma to small bowel.
DIAGNOSIS ? [FIGURE 25.10]
ABDOMINAL AORTIC ANEURYSM
Conventional radiograph demonstrates an aneurysm of the abdominal aorta evidenced by wide separation of calcifications in the aortic wall (arrowheads).
Calcification in the wall overlying the spine may be difficult to visualize.
A radiograph taken with the patient in left posterior oblique position will project the aorta away from the spine and make visualization of aortic wall calcifications easier.
RETROPERITONEAL COMPARTMENTAL ANATOMY
[FIGURE 25.3]
Diagrams illustrate two normal variations of the reflections of the posterior parietal peritoneum around the descending colon. In (A) the colon is entirely retroperitoneal and in (B) the peritoneum forms a deep pocket lateral to the colon, allowing intraperitoneal fluid to extend far posteriorly.
Fluid or disease processes in the anterior pararenal space from the pancreas or colon may also extend posteriorly to the kidney by separating the two layers of the posterior renal fascia.
IDENTIFY THE RADIOGRAPHIC FINDING.
[FIGURE 25.16]
CALCIFIED RENAL CYST
Conventional radiograph shows the rim calcifi cation (arrow) characteristic of wall calcification in a renal cyst.
DIAGNOSIS ? [FIGURE 25.39]
INCARCERATED INGUINAL HERNIA
In a patient with acute right pelvic pain, a sagittal plane–reconstructed CT shows a loop of small bowel (arrow) extending into the inguinal canal (between arrowheads). The bowel contained within the hernia is swollen and edematous with thickened bowel walls, signs of incarceration that were confirmed at surgery.
DIAGNOSIS ?
[FIGURE 25.38]
ABSCESS
CT reveals an abscess (arrows) in the retroperitoneum.
The abscess contains fluid and gas (arrowhead). Note the
discrete enhancing wall of the abscess. Duodenum ( D ) containing intraluminal gas is displaced anteriorly and is draped over the collection.
DIAGNOSIS ? [FIGURE 25.37]
RETAINED SURGICAL SPONGE
A. Digital radiograph of the abdomen taken at bedside reveals the characteristic radiopaque tape (arrow) that marks a surgical sponge inadvertently left within the abdominal cavity. Metallic cutaneous staples identify the patient as having had
recent surgery.
B. CT reveals the difficulty of identifying the surgical sponge if the radiopaque marker (arrow) was not present. The sponge
(between arrowheads) contains fl uid, blood, and air bubbles producing a pattern very similar to stool in the colon. The descending colon (curved arrow) is displaced medially.
DIAGNOSIS ? [FIGURE 25.34]
LIPOSARCOMA
CT shows a large liposarcoma (arrows) that arose in the retroperitoneum as a mottled fat-density mass that distorts the inferior vena cava (IVC), surrounds the aorta
(Ao) and displaces small and large bowel (B) laterally.
DIAGNOSIS ? [FIGURE 25.8]
PNEUMOPERITONEUM: Conventional Radiograph
A. Supine abdominal radiograph of a patient with a perforated gastric ulcer demonstrates visualization of both sides of the bowel wall (Rigler sign) (arrowheads) , free air outlining the falciform ligament (arrow), free air outlining the edge of the liver (curved arrow) , and free air outlining the pericolic gutters (asterisk).
B. Erect chest radiograph of a different patient shows
a crescent-shaped band of gas (arrow) between the liver (L) and the diaphragm. Pneumoperitoneum was caused by a perforated sigmoid colon diverticulitis.
COMPARTMENTAL ANATOMY OF THE PELVIS
[FIGURE 25.4]
Diagram in the coronal plane illustrates the major anatomic compartments of the pelvis.
DIAGNOSIS ?
IDENTIFY THE RADIOLOGIC SIGN.
[FIGURE 25.33]
PERITONEAL METASTASES;
OMENTAL CAKE
A CT scan demonstrates intraperitoneal spread of ovarian carcinoma. The tumor is implanted
on the omentum (arrows), causing the appearance of “omental cake” as the thickened omentum fl oats in ascites (A) between bowel loops and the abdominal wall.
Nodules of tumor (arrowhead) are implanted on the peritoneal surface.
IDENTIFT THE TWO RADIOLOGIC FINDINGS.
[FIGURE 25.29]
HEMOPERITONEUM and SENTINEL CLOT
CT scan shows high-attenuation fluid in the peritoneal recesses indicating hemoperitoneum (H). A sentinel clot (arrow) stands out as a high-attenuation collection within the lower-attenuation liquid blood. The location of the clot suggests injury to the liver
(L).
A laceration of the left lobe of the liver, not evident on the CT, was found at surgery.
DIAGNOSIS ? {FIGURE 25.12]
STAGHORN CALCULUS
Conventional radiograph reveals a large calculus occupying the collecting system of the left kidney and assuming its shape. Staghorn calculi (S) are usually composed of struvite
and form in the presence of chronic urinary infection.
IDENTIFY THE NORMAL ANATOMIC STRUCTURE.
[FIGURE 25.5]
POUCH OF DOUGLAS
A CT of the pelvis in a woman with abundant ascites demonstrates fluid distension of the pouch of Douglas (PD) (cul-de-sac) posterior to the uterus (U) and anterior to the rectum (curved arrow). The broad ligament (long arrows) is outlined by fluid anteriorly and posteriorly.
IDENTIFY THE RADIOGRAPHIC FINDINGS.
[FIGURE 25.14]
ADRENAL CALCIFICATIONS
Conventional radiograph of the abdomen in a 4-year-old demonstrates calcification of both adrenal glands (arrows) resulting from bilateral adrenal hemorrhage as an
infant.
IDENTIFY THE RADIOLOGIC FINDING AND ITS CAUSE.
[FIGURE 25.30]
ACTIVE HEMORRHAGE - LIVER LACERATION
CT shows a jagged laceration (arrowheads) of the liver (L) filled with blood. A focus of continuing active hemorrhage (arrow) is seen as an ill-defined collection of high-attenuation contrast agent.
Hemoperitoneum (H) is evident in the peritoneal recesses. Sp, spleen; St, stomach.
