CT gastrography

The rapid dissemination of multidetector-row computed tomographic (CT) technology will make faster and more accurate gastric imagining available. Two-dimensional multiplanar reconstruction and CT gastrography including virtual gastroscopy and transparency rendering using volume rendering are types of interactive two- and three-dimensional medical imaging tools. It provides multiplanar cross-sectional imaging, gastroscopic viewing, and upper gastrointestinal series imaging in the same data acquisition. Two-dimensional multiplanar reconstruction provides accurate staging of gastric cancer and extraluminal information such as lymphadenopathy and distant metastasis. Virtual gastroscopy detects subtle mucosal changes and differentiates them from submucosal lesions in the same way as gastroscopy. Transparency rendering provides global orientation of the focal findings in the stomach in the same way as upper gastrointestinal series findings and provides useful information for preoperative mapping. Thus, CT gastrography is a promising method for evaluating gastric lesion despite its limitations.

Early gastric cancer: virtual gastroscopy

Gastric cancer is one of the most common cancers and one of the most frequent causes of cancer-related deaths worldwide. Early detection and accurate preoperative staging of early gastric cancer (ECG) offers the best prognosis and is essential for planning optimal therapy such as endoscopic mucosal resection or gastric resection. Recent advances in computed tomographic technology and three-dimensional imaging software have enabled more accurate gastric imaging. Virtual gastroscopy (VG) is helpful in the detection and evaluation of EGC in the same way as gastroscopy. VG has a wider field of view than conventional gastroscopy, the angle of the virtual cancer can be adjusted omnidirectionally, and it has no blind point because retrospective reconstruction is available. Thus, VG is a promising method for evaluating gastric lesions despite its limitations. This report describes the clinical usefulness of VG with multidetector row computed tomography for EGC and axial computed tomography.

Milk of calcium in a pancreatic pseudocyst

A 46-year-old man with a history of chronic alcohol use was found to have milk of calcium that had developed in a pancreatic pseudocyst. This was found incidentally on abdominal computed tomography during a workup for abnormal liver enzymes. Milk of calcium in the pancreas has been described only twice in the literature using plain abdominal radiographs and computed tomography. To our knowledge, this case report is the first to describe magnetic resonance findings of this entity.

CT analysis of postoperative tumor recurrence patterns in periampullary cancer

BACKGROUND

We analyzed postoperative tumor recurrence in periampullary cancer on computed tomography (CT).

METHODS

Forty-six patients with tumor recurrence (16 pancreas head cancers, 19 distal common bile duct cancers, and 11 ampulla of Vater cancers) of 125 patients who underwent surgery for periampullary cancer were enrolled. Recurrence was diagnosed by CT findings plus elevated CA 19-9 (n = 28) or biopsy (n = 18). Two radiologists retrospectively reviewed 156 contrast-enhanced CT scans, with 7-mm slice thickness, obtained in our institution until the initial diagnosis of tumor recurrence. The modes of recurrence were classified as local recurrence, hepatic metastasis, lymph node metastasis, peritoneal carcinomatosis, or extraabdominal metastasis. We evaluated the time of recurrence, the frequency of each mode of recurrence, and the earliest mode of recurrence. The differences in tumor recurrence for the three types of periampullary cancer were evaluated.

RESULTS

Half of the recurrences occurred within 6 months after surgery and 87% occurred within 12 months after surgery. Local recurrences (67%), hepatic metastases (72%), and lymph node metastases (61%) were common modes of tumor recurrence. Pancreas head cancers recurred earlier than the other types of periampullary cancer (p < 0.05).

CONCLUSION

Periampullary cancer tends to recur early after surgery, usually as a local recurrence, hepatic metastasis, or lymph node metastasis.

Intragastric metastasis in a patient with gastric cancer: unusual CT manifestation

We describe computed tomographic findings of intragastric metastasis in a patient with gastric cancer. On computed tomography, the intragastric metastatic lesion appeared as an exophytically growing cystic masss with minimal thickening of the adjacent gastric wall, thus mimicking an exophytically growing submucosal tumor or adenocarcinoma.

CT differentiation of mesenteric ischemia due to vasculitis and thromboembolic disease

PURPOSE

The purpose of this work was to differentiate CT findings of acute mesenteric ischemia due to vasculitis (MV) or thromboembolism (MTE).

METHOD

CT scans of 69 patients with mesenteric ischemia caused by MV (n = 37) or MTE (n = 32) were analyzed. After dividing the patients into groups with and without MV, we compared them with regard to gastrointestinal tract involvement patterns, mesenteric changes, and presence or absence of vascular thrombosis, atherosclerosis, other organ changes, and ascites.

RESULTS

Duodenum was involved only in the MV group (30%). The MV group had preferential involvement of the small intestine (89%) to large intestine (51%), whereas the MTE group showed even distribution. Multisegmental bowel involvement was more common in the MV group (86%) than in the MTE group (44%), especially in both jejunum and ileum and both small and large intestine. The MV group showed prominent involvement of the superior mesenteric vessel territory, although the MTE group showed even distribution. Splenomegaly and hydronephrosis were more frequently seen in the MV group and vascular thrombosis and atherosclerosis in the MTE group.

CONCLUSION

Although considerable overlap was noted, CT is useful in differentiating MV from MTE.

Abdominopelvic actinomycosis involving the gastrointestinal tract: CT features

PURPOSE

To assess the computed tomographic (CT) features of abdominopelvic actinomycosis involving the gastrointestinal tract.

MATERIALS AND METHODS

CT scans were analyzed in 18 patients with pathologically proved abdominopelvic actinomycosis involving the gastrointestinal tract. Eight patients had a history of using intrauterine contraceptive devices. Bowel site, wall thickness, length, bowel involvement patterns, inflammatory infiltration, and features of peritoneal or pelvic mass, if present, were evaluated at CT.

RESULTS

Of the gastrointestinal tract, the sigmoid colon was most commonly involved (50%). All patients showed concentric (n = 15) or eccentric (n = 3) bowel wall thickening, with a mean thickness of 1.2 cm and a mean length of 8.3 cm. The thickened bowel enhanced homogeneously in nine patients and heterogeneously in the other nine. Inflammatory infiltration was mostly diffuse and severe. In 17 patients, a peritoneal or pelvic mass (mean maximum diameter, 3.2 cm) was seen adjacent to the involved bowel and appeared to be heterogeneously enhanced in most cases; infiltration into the abdominal wall was seen in four patients.

CONCLUSION

Actinomycosis should be included in the differential diagnosis when CT scans show bowel wall thickening and regional pelvic or peritoneal mass with extensive infiltration, especially in patients with abdominal pain, fever, leukocytosis, or long-term use of intrauterine contraceptive devices.

CT features of primary colorectal signet-ring cell carcinoma

PURPOSE

The purpose of this work was to evaluate the CT features of 15 patients with primary colorectal signet-ring cell carcinomas.

METHOD

We retrospectively reviewed the CT scans of 15 patients (mean age 44 years) with pathologically proved colorectal signet-ring cell carcinoma. On CT, we evaluated the site and length of the tumor, bowel wall thickening patterns, perirectal or pericolic infiltration, the presence or absence of colonic obstruction, and metastasis to other organs.

RESULTS

The tumors were located in the rectum in nine patients, the sigmoid colon in one, the hepatic flexure in one, the transverse colon in one, the ascending colon in two, and the cecum in one. The tumor length ranged from 4.0 to 10.0 cm (mean 6.1 cm) with mean thickness of 2.1 cm. CT showed concentric bowel wall thickening in all patients ("even" in 8 and "uneven" in 7), target appearance was noted in 4, perirectal or pericolic infiltrations were moderate to severe in 12, and colorectal obstruction was seen in 6. In the tumor spread patterns, lymphadenopathy was noted in 13, invasion to adjacent pelvic organs in 5, peritoneal carcinomatosis in 4, liver metastasis in 2, and periureteric metastasis in 1.

CONCLUSION

Primary signet-ring cell colorectal carcinoma should be included for differential consideration when CT shows a long length of concentric bowel wall thickening and target sign, especially when such findings occur in the rectum and in young patients.

Pelioid-type hepatocellular carcinoma masquerading as a hepatic hemangioma on technetium-99m red blood cell scintigraphy

Technetium-99m red blood cell (RBC) scintigraphy is a very specific method to differentiate a hemangioma from other hepatic masses. The authors report a case of hepatocellular carcinoma that showed a focal area of increased uptake on Tc-99m RBC SPECT in a 60-year-old man. Dynamic computed tomography and angiography revealed features of both hemangioma and hepatocellular carcinoma. Pathologic examination showed that the portion of the hepatocellular carcinoma that showed increased uptake on Tc-99m RBC scintigraphy had peliosis, which is the likely cause of the radiotracer avidity.

Diagnostic pitfalls in the cholangiographic diagnosis of choledochoceles: cholangiographic quality and its effect on visualization

BACKGROUND

We wanted to establish reasonable cholangiographic diagnostic criteria by determining the sensitivity of cholangiography in detecting choledochoceles and those factors that could compromise visualization of choledochoceles.

METHODS

Over 4 years, 21 patients (seven male, 14 female; mean age = 67 years) were confirmed as having choledochoceles on endoscopic retrograde cholangiopancreatography (ERCP). Cholangiographic diagnosis was made by following three criteria: a radiolucent halo around the distal common bile duct (CBD), bulbous dilatation of the distal CBD, and the presence of sequential morphologic changes on serial cholangiography. Any two or more combinations of these three criteria were considered enough to diagnose a choledochocele on cholangiography. We compared cholangiographic imaging findings with the ERCP results.

RESULTS

Of 21 patients with choledochoceles, nine (43%) were correctly diagnosed on cholangiography. A radiolucent halo was present in six (28%) patients; four of these cases showed optimal duodenal filling, one showed faint duodenal filling, and one showed poor duodenal filling. The shapes of the distal CBD were bulbous, conelike, and blunt. Morphologic changes such as collapsing and bulging of the choledochocele could be seen in 12 (57%) patients on serial cholangiography. Waists were seen in 11 (52%), pseudowebs in four (19%), and wrinkling of the distal CBD in seven (33%).

CONCLUSION

Cholangiography should be obtained with optimal timing and adequate conditions to diagnose choledochocele correctly.

Malignant papillary neoplasms of the intrahepatic bile ducts: CT and histopathologic features

OBJECTIVE. We describe the CT and pathologic features of malignant papillary neoplasms of the intrahepatic bile ducts in 15 patients. CONCLUSION. CT is a useful technique for revealing intraductal lesions, although the findings are nonspecific and variable. When intraductal masses or nodules are seen with localized dilatation of the intrahepatic bile ducts on CT scans, malignant papillary neoplasms of the intrahepatic bile ducts should be included in the differential diagnosis.

Radiologic findings of abdominal polyarteritis nodosa

OBJECTIVE

The purpose of this study was to evaluate the radiographic and imaging findings of seven patients with polyarteritis nodosa involving the abdomen.

CONCLUSION

Vasculitis should be considered when multiple abdominal organs have abnormal radiologic findings; however, angiography is necessary to specifically diagnose polyarteritis nodosa.

Radiological features of leiomyomatous tumors of the colon and rectum

PURPOSE

The purpose of this study was to evaluate the radiological features of 12 pathologically proven cases of colorectal leiomyomatous tumors.

METHOD

A retrospective analysis of radiologic findings was performed in 12 patients with pathologically proven colorectal leiomyomatous tumors (2 leiomyomas and 10 leiomyosarcomas). Available radiologic studies included abdominal CT scans in 11 patients, double contrast barium studies in 4, and pelvic MRI in 1. On imaging, we evaluated the size, tumor margin (smooth or lobulated), morphologic appearance, growth patterns (endocolic, exocolic, or combined), contrast enhancement patterns, presence or absence of calcification within the tumors, and metastasis.

RESULTS

The involved tumor sites were the colon in 2 patients and the rectum in 10. The mean tumor size was 7.9 cm (range 2-15 cm): It was 3.5 cm in leiomyomas and 8.8 cm in leiomyosarcomas. On imaging studies, the tumor margin was smooth in three patients and lobulated in nine, with endocolic growth in one, exocolic in four, and combined in the remaining seven. Eight of the 12 tumors showed varying degrees of internal necrosis with heterogeneous contrast enhancement. Dystrophic calcification was noted in five patients. Metastasis was seen in the liver in three patients at the time of initial diagnosis, and lymphadenopathy was noted in two patients (paraaortic space in one and perirectal space in two).

CONCLUSION

Although rare, the diagnosis of leiomyomatous tumor may be suggested especially when the tumor occurring in the colorectum shows exocolic growth or calcification with varying degree of internal necrosis.

Radiologic features of vasculitis involving the gastrointestinal tract

Vasculitides can cause local or diffuse pathologic changes in the gastrointestinal tract, resulting in nonspecific paralytic ileus, mesenteric ischemia, submucosal edema and hemorrhage, or bowel perforation or stricture. The extent and clinical course of disease depend on the size and location of the affected vessel and the histologic characteristics of the lesion. Vasculitis may primarily involve large vessels (eg, giant cell arteritis, Takayasu arteritis), medium-sized vessels (eg, polyarteritis nodosa, Kawasaki disease, primary granulomatous central nervous system vasculitis), or small vessels (eg, Wegener granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, Henoch-Schönlein syndrome, systemic lupus erythematosus, rheumatoid vasculitis, Behçet syndrome). Radiologic findings in various types of vasculitis often overlap considerably and therefore have limited value in making a specific diagnosis. Nevertheless, the possibility of vasculitis should be considered whenever mesenteric ischemic changes occur in young patients, are noted at unusual sites (eg, stomach, duodenum, rectum), have a tendency to concomitantly involve the small and large intestine, and are associated with genitourinary involvement. Knowledge of systemic clinical manifestations in affected patients may suggest and even help establish the specific diagnosis.

Nodular regenerative hyperplasia of the liver in Budd-Chiari syndrome: CT and MR features

We report the imaging findings of spiral computed tomography (CT), magnetic resonance (MR) imaging, and MR angiography in a patient with nodular regenerative hyperplasia of the liver associated with Budd-Chiari syndrome. Spiral CT showed multiple enhancing nodules during the hepatic arterial and portal venous phases. MR images showed multiple hyperintense nodules on T1-weighted images and hypointense or isointense nodules on T2-weighted images. MR angiography showed thrombotic occlusion of three hepatic veins, suggesting Budd-Chiari syndrome.

CT features of metastatic linitis plastica to the rectum in patients with peritoneal carcinomatosis

OBJECTIVE

We examined the CT features of 22 patients with metastatic linitis plastica to the rectum.

CONCLUSION

Metastatic linitis plastica to the rectum should be considered when CT shows a long segment of circumferential rectal wall thickening, especially in patients with peritoneal carcinomatosis from gastric cancer. In such patients, CT helps avoid unnecessary extensive surgery.

CT and MR diagnoses of intestinal ischemia

CT and MR imaging have an important role in establishing the diagnosis of mesenteric ischemia. However, without specific signs such as thromboembolism in the mesenteric vessel, intramural or portal venous gas, and the absence of bowel wall enhancement, mesenteric ischemia can be confused with inflammatory or neoplastic gastrointestinal diseases. Arterial or venous occlusion or low-flow state are the main direct causes of mesenteric ischemia. Delayed diagnosis in equivocal cases can be avoided through an understanding of the patholophysiological aspects of mesenteric ischemia as they occur in a variety of other conditions, including: thromboembolism, bowel obstruction, neoplasm, vasculitis, inflammatory diseases, trauma, and drug or radiation therapy.

CT and MR imaging findings of bowel ischemia from various primary causes

Ischemic bowel disease represents a broad spectrum of diseases with various clinical and radiologic manifestations, which range from localized transient ischemia to catastrophic necrosis of the gastrointestinal tract. The primary causes of insufficient blood flow to the intestine are diverse and include thromboembolism, nonocclusive causes, bowel obstruction, neoplasms, vasculitis, abdominal inflammatory conditions, trauma, chemotherapy, radiation, and corrosive injury. Computed tomography (CT) or magnetic resonance (MR) imaging can demonstrate the ischemic bowel segment and may be helpful in determining the primary cause. The CT and MR imaging findings include bowel wall thickening with or without the target sign, intramural pneumatosis, mesenteric or portal venous gas, and mesenteric arterial or venous thromboembolism. Other CT findings include engorgement of mesenteric veins and mesenteric edema, lack of bowel wall enhancement, increased enhancement of the thickened bowel wall, bowel obstruction, and infarction of other abdominal organs. However, regardless of the primary cause, the imaging findings of bowel ischemia are similar. Furthermore, the bowel changes simulate inflammatory or neoplastic conditions. Understanding the pathogenesis of various conditions leading to mesenteric ischemia helps the radiologist recognize ischemic bowel disease and avoid delayed diagnosis, unnecessary surgery, or less than optimal management.

Usefulness of MR imaging for diseases of the small intestine: comparison with CT

OBJECTIVE

To evaluate the usefulness of MR imaging for diseases of the small intestine, emphasizing a comparison with CT.

MATERIALS AND METHODS

Thirty-four patients who underwent both CT and MR imaging using FLASH 2D and HASTE sequences were analyzed. All patients had various small bowel diseases with variable association of peritoneal lesions. We compared the detectabilities of CT and MR imaging using different MR pulse sequences. The capability for analyzing the characteristics of small intestinal disease was also compared.

RESULTS

MR imaging was nearly equal to CT for detecting intraluminal or peritoneal masses, lesions in the bowel and mesentery, and small bowel obstruction, but was definitely inferior for detecting omental lesions. The most successful MR imaging sequence was HASTE for demonstrating bowel wall thickening, coronal FLASH 2D for mesenteric lesions, and axial FLASH 2D for omental lesions. MR imaging yielded greater information than CT in six of 12 inflammatory bowel diseases, while it was equal to CT in six of seven neoplasms and inferior in five of seven mesenteric ischemia. In determining the primary causes of 15 intestinal obstructions, MR imaging was correct in 11 (73%) and CT in nine (60%) patients.

CONCLUSION

MR imaging can serve as an alternative diagnostic tool for patients with suspected inflammatory bowel disease, small intestinal neoplasm or obstruction.

Fast T2-weighted liver MR imaging: comparison among breath-hold turbo-spin-echo, HASTE, and inversion recovery (IR) HASTE sequences

BACKGROUND

To evaluate the diagnostic efficacy of fast T2-weighted magnetic resonance (MR) imaging sequences on image quality, hepatic lesion detection, and lesion conspicuity.

METHODS

Three breath-hold, fast T2-weighted sequences with turbo-spin-echo (TSE), half-Fourier acquisition single-shot TSE (HASTE), and inversion recovery (IR) HASTE techniques were examined for 43 lesions in 20 consecutive patients. Evaluation was performed qualitatively on image quality and lesion detectability and quantitatively on lesion conspicuity by using lesion/liver signal-intensity and contrast-to-noise ratios.

RESULTS

Artifacts were significantly less present on the HASTE sequence (p < 0.01). Both TSE and HASTE sequences detected 39 lesions (91% each); the IR HASTE sequence detected 37 (86%). IR HASTE sequence showed a significantly higher signal-intensity ratio than did the others (p < 0.01).

CONCLUSIONS

Breath-hold TSE versus breath-hold HASTE or IR HASTE is still the most robust sequence in lesion detection, image quality, and lesion conspicuity. However, the HASTE sequence offers good lesion detection and image quality, and the IR HASTE has a better signal-intensity ratio.

CT features of torsion of benign cystic teratoma of the ovary

PURPOSE

The purpose of this work was to evaluate the usefulness of CT scans for distinguishing torsed from uncomplicated benign cystic teratoma (BCT).

METHOD

Retrospective analysis was performed in 14 torsed BCTs (14 patients) and in 23 uncomplicated BCTs (20 patients) for comparison. The features on CT scans were compared to the pathologic findings.

RESULTS

CT findings indicating torsed BCT were the presence of eccentric wall thickening of >1 cm, peritumoral infiltration, and presence of enlarged solid tubal mass adjacent to the uterus (p < 0.05).

CONCLUSION

The present study suggests that CT is useful in differentiating torsed from uncomplicated BCT. Although CT findings are not specific for some patients, detection of certain CT findings could increase the diagnostic accuracy.

CT features of abdominal manifestations of primary antiphospholipid syndrome

PURPOSE

The purpose of this work was to evaluate the CT features of the abdominal manifestations of primary antiphospholipid syndrome (PAPS).

METHOD

Of the 32 patients who were confirmed to have PAPS among 751 patients with elevated antiphospholipid antibodies during a 2 year period, we retrospectively reviewed the 14 patients who underwent abdominal CT. The clinical indications for abdominal CT included abdominal pain, abdominal distension, or lower leg swelling. CT findings were analyzed with regard to the abdominal vascular system and abdominal organ involvement patterns as well as ancillary findings.

RESULTS

Of the 14 patients with PAPS, 10 had involvement of the venous system (72%), 2 of the arterial system (14%), and 2 of both systems (14%). Of the 12 patients who had venous system involvement, 4 had thrombosis in the inferior vena cava (IVC), 2 in both the IVC and the hepatic vein, 1 in the IVC and splenic and portal veins, 1 in the IVC and hepatic and adrenal veins, 1 in the hepatic, portal, and renal veins, and 3 in the portal and superior mesenteric veins. Budd-Chiari syndrome developed in five of the nine patients who had thrombosis of the IVC or hepatic vein. Arterial thrombosis was noted in four patients, hepatic artery in two, aorta in one, renal artery in one, pancreatic arcade in one, and splenic artery in one, with infarct of multiple organs including the liver, jejunum, colon, kidney, and adrenal gland. Seven of the 14 patients (50%) manifested thrombosis or infarct of multiple extra-abdominal organs.

CONCLUSION

PAPS should be included in the differential diagnosis when CT demonstrates infarcts in multiple organs or patients have recurrent episodes of venous or arterial thrombosis.

Fetus-in-fetu in the scrotal sac of a newborn infant: imaging, surgical and pathological findings

We report a case of fetus-in-fetu located in the scrotal sac of a newborn male infant. Plain radiography (including specimen radiography), ultrasonography and MRI clearly demonstrated vertebral column, ribs, skull, pelvic bones, femurs and a portion of tibiae and humeri. The diagnosis was confirmed by pathological examination.

CT features of intraperitoneal manifestations of parasitic infestation

OBJECTIVE

The purpose of this study was to evaluate the CT features of intraperitoneal manifestations with parasitic infestation in nine patients.

CONCLUSION

The CT features of intraperitoneal manifestations of parasitic infestation were single or multiple multiseptated cystic masses in the peritoneal cavity, hazy omental infiltration, or both. Recognizing these features is important to establish an early diagnosis that leads to rapid treatment and helps avoid unnecessary surgery.

Inflammatory pseudotumor of the liver in patients with recurrent pyogenic cholangitis: CT-histopathologic correlation

PURPOSE

To correlate computed tomographic (CT) features of inflammatory pseudotumors of the liver with histopathologic results in patients with recurrent pyogenic cholangitis.

MATERIALS AND METHODS

CT features of 13 cases of inflammatory hepatic pseudotumor in 10 patients with recurrent pyogenic cholangitis were reviewed. Diagnosis was made by means of surgical resection in all patients. CT scans were analyzed for the appearance of masses and ancillary findings in correlation with the histopathologic findings in each resected specimen.

RESULTS

The masses were 2.0-7.0 cm (mean, 3.5 cm). At nonenhanced CT, the masses appeared as ill-defined, hypoattenuating lesions. At contrast material-enhanced CT, the masses exhibited central hypoattenuating areas with an iso- or hyperattenuating thickened periphery in four cases and a multiseptate appearance with hyperattenuating internal septa and periphery in nine cases. CT-histopathologic correlation showed that the central hypoattenuating area indicated the presence of chronic inflammatory infiltrates with foamy histiocytes, plasmacytes, and lymphocytes, while iso- or hyperattenuating areas in the periphery and internal septa of the mass represented fibroblastic proliferation. All patients had CT features of recurrent pyogenic cholangitis, such as hepatolithiasis, intrahepatic duct stricture and dilatation, common bile duct calculi, pneumobilia, or parenchymal atrophy.

CONCLUSION

Although CT features are not specific, inflammatory pseudotumor should be included in the differential diagnosis in patients with recurrent pyogenic cholangitis and a hepatic mass detected at CT.

Modified small-bowel follow-through: use of methylcellulose to improve bowel transradiance and prepare barium suspension

PURPOSE

To evaluate the efficacy of barium suspension prepared in methylcellulose (MC) in modified small-bowel follow-through (SBFT).

MATERIALS AND METHODS

The authors evaluated 155 patients who underwent modified SBFT with oral administration of MC after ingesting barium suspension. Of these patients, 52 received 40% suspension in MC, 46 received 40% suspension in water, and 57 received 70% suspension in water. Patients were divided into normal (n = 74) and abnormal (n = 81) groups according to the final results. The image quality, transit time to the cecum, and time to and frequency of flocculation were compared for both groups.

RESULTS

In the normal group, the quality of the images in patients receiving 40% suspension in MC or 70% suspension in water was superior to that of images in patients receiving 40% suspension in water. In the abnormal group, the best image quality was achieved for the patients who received 40% suspension in MC. In the normal group, the difference in transit time between the three preparations was not substantial. In the abnormal group, however, the 40% suspension in MC showed the fastest transit time. Use of the 40% suspension in MC helped lower the frequency of flocculation in the normal group.

CONCLUSION

Use of 40% barium suspension in MC is effective for improving the image quality in modified SBFT.

Percutaneous hot saline injection therapy: effectiveness in large hepatocellular carcinoma

PURPOSE

To report on the efficacy of percutaneous hot saline injection therapy (PSIT) in the treatment of large hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Twenty-nine patients with 31 HCCs underwent PSIT. Physiologic saline was mixed with contrast medium and Lipiodol; this mixture was boiled and injected into the tumor. Mean tumor diameter was 7.0 cm. Initial regression rates were evaluated at 3-month interval with computed tomography (CT) and alpha-fetoprotein level measurement. Cumulative survival rates were calculated with the Kaplan-Meier method. Multivariate analysis using Cox's proportional hazard regression model was performed to determine the significant prognostic factors.

RESULTS

Initial regression rate for all tumors at a 3-month interval was 42% (13 of 31 tumors) and the median survival was 10.0 months (range, 3.0-36.0 months). The significant prognostic factors were encapsulated tumors, tumors less than 10 cm in diameter, tumors with even saline dispersion, tumors with initial regression at 3-month follow-up, and TNM stage II or III rather than IV.

CONCLUSION

PSIT is a feasible alternative treatment for a large HCC when transcatheter arterial chemoembolization is not feasible or has failed.

Xanthogranulomatous cholecystitis: radiologic findings with histologic correlation that focuses on intramural nodules

OBJECTIVE

The purpose of this study was to histologically classify intramural nodules associated with xanthogranulomatous cholecystitis and to evaluate the radiologic findings for each type of nodule.

MATERIALS AND METHODS

Pathologic slides and radiologic studies including 14 sonographic and 16 CT examinations in 19 patients (12 men, seven women; mean age, 61 years) with xanthogranulomatous cholecystitis were reviewed. Radiologic findings were correlated with the histologic type of intramural nodule: abscess, xanthogranuloma, or a combination of the two. The duration of symptoms for each type of intramural nodule was also evaluated.

RESULTS

Histologically, all patients had intramural nodules that were either abscesses (n = 11), xanthogranulomas (n = 5), or a combination of the two (n = 3). Radiologic studies revealed nodules in 10 patients (52.6%; four abscesses, four xanthogranulomas, and two combinations). For abscesses, the mean interval from onset of symptoms to surgery was 25 days; for xanthogranulomas, 70 days (p = .0057). Abscesses were associated with more complications of xanthogranulomatous cholecystitis.

CONCLUSION

Intramural nodules in patients with xanthogranulomatous cholecystitis were found to represent abscesses or xanthogranulomas at histology. Xanthogranulomas were more often revealed radiologically than were abscesses. Abscesses caused more clinical complications. Because symptoms lasted longer for xanthogranulomas, we hypothesized that abscesses may become xanthogranulomas.

Colonic wall thickening in cirrhotic patients: CT features and its clinical significance

BACKGROUND

To evaluate the computed tomographic (CT) features of colonic wall thickening in cirrhotic patients and to determine their prognostic value.

METHODS

We retrospectively reviewed 28 cirrhotic patients with colonic wall thickening (>/=10 mm) on CT. Twenty-six of the 28 patients had hepatocellular carcinoma. The severity of hepatic dysfunction was determined by using the Child-Pugh classification. We analyzed the patterns of bowel wall thickening and degree of portal hypertension on CT and the survival periods after initial CT detection of colonic wall thickening.

RESULTS

The involved segment of the colon was diffusely thickened with either scalloped or nodular circumferential configuration. In all patients, the thickened colonic wall enhanced poorly. Although the ascending colon was involved in all patients, the transverse (n = 14) or descending (n = 5) colon was also simultaneously involved. Most patients exhibited an advanced stage of portal hypertension on CT. The median survival period of 25 patients who expired was 34 days, and 21 patients (84%) expired within 3 months.

CONCLUSIONS

Colonic wall thickening on CT can be used as one of the indicators of poor prognosis in cirrhotic patients. Advanced liver cirrhosis with significantly severe dysfunction is the likely cause of mortality. Therefore, a less aggressive therapeutic approach is recommended if hepatocellular carcinoma is coexistent in these patients.

Intestinal tuberculosis with abdominal complications: radiologic and pathologic features

BACKGROUND

To investigate radiologic and pathological features of intestinal tuberculosis with abdominal complications.

METHODS

Twenty-two patients with 23 surgically proven complications (nine intestinal obstructions, eight perforations, three fistulae, and three intestinal bleeds) were analyzed. Medical records, radiologic studies, and pathologic examinations were reviewed with special emphasis on searching for the common features in each group of complication.

RESULTS

The most important single feature in seven of the nine patients with intestinal obstruction was the presence of stricture. In the remaining two patients, bowel adhesion was a primary cause of obstruction. In eight patients with intestinal perforation, both obstruction and ulcerations in the dilated proximal loop were the important features in six, and multiple deep ulcerations without obstruction was a primary cause in the remaining two. The common features in three patients with fistulae were focal or multiple strictures, severe adhesions, and fibrotic bowel wall. Intestinal bleeding originated from diffuse mucosal ulcerations. The abdominal complications occurred during antituberculous therapy in 10 of the 22 patients.

CONCLUSION

Understanding the radiologic and pathologic features of intestinal tuberculosis with complications help in making an appropriate clinical decision for the treatment strategy. Close observation is necessary, especially in those patients who are acutely ill during antituberculous medical therapy. Enteritis-Intestines, diseases-Intestines, infection-Intestines, perforation-Intestines, stenosis or obstruction.

Usefulness of CT in patients with intestinal obstruction who have undergone abdominal surgery for malignancy

OBJECTIVE

The purpose of this study was to evaluate the usefulness of CT in determining the causes of intestinal obstruction in patients who have undergone abdominal surgery for malignancy.

MATERIALS AND METHODS

We analyzed the CT scans of 55 patients with benign (n = 26) or malignant (n = 29) intestinal obstruction that developed after abdominal surgery for malignancy. After calculating the diagnostic accuracy of interpretations by three radiologists, we compared CT findings for benign and malignant intestinal obstructions with respect to peritoneal involvement patterns and other ancillary findings. Multivariate logistic regression analysis was used to determine the diagnostic performance of CT in revealing causes of obstruction.

RESULTS

Diagnostic accuracies of the three radiologists were 67%, 75%, and 78%. CT findings indicating malignant obstruction were a mass at the site of obstruction or prior surgery, lymphadenopathy, or an abrupt transition zone and irregular bowel wall thickening at obstructed sites (p < .05). Conversely, the chance for benign obstruction increased when CT revealed mesenteric vascular changes, a large amount of ascites, or a smooth transition zone and smooth bowel wall thickening at the obstructed site (p < .05). With multivariate logistic regression analysis using two variables (a mass at the site of obstruction or prior surgery and lymphadenopathy), we calculated the overall accuracy of CT as 84% (46/55 patients).

CONCLUSION

CT is useful in differentiating benign from malignant intestinal obstructions in patients who have undergone abdominal surgery for malignancy. However, CT has limitations in patients not having a demonstrable peritoneal mass.

MR cholangiopancreatography of pancreaticobiliary diseases: comparing single-shot RARE and multislice HASTE sequences

OBJECTIVE

In this study, we compared the single-shot rapid acquisition with relaxation enhancement (RARE) sequence with the multislice half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence to assess the ability of each technique to show various pancreaticobiliary diseases using MR cholangiopancreatography.

SUBJECTS AND METHODS

MR cholangiopancreatography was performed using both the single-shot RARE and the multislice HASTE pulse sequences in 80 consecutive subjects in whom we had proof of a range of diagnoses. The study population included healthy subjects (n = 9), patients with benign lesions (n = 41), and patients with malignant lesions (n = 30). We analyzed each image using the following criteria: the cause of the lesions, the image quality (i.e., the amount of artifact and the sharpness of anatomic structures such as the right and left hepatic ducts, the extrahepatic bile duct, and the main pancreatic duct), and the reviewers' preference of images. The images were evaluated independently by two radiologists who were unaware of the results of the other cholangiopancreatographic sequence and of the diagnosis.

RESULTS

Artifacts were less prominent in images that were obtained using the single-shot RARE sequence (p = .0192); however, the sharpness of anatomic structures was the same using either sequence (p = .1673). For images that were obtained using the single-shot RARE technique, the sensitivity, specificity, and accuracy in distinguishing malignant from other abnormalities were 83%, 78%, and 80%, respectively; for the multislice HASTE technique, these values were 77%, 72%, and 74%, respectively (p > .05). Disease-specific accuracy in determining the correct diagnosis was 54% and 59%, respectively (p > .05). In patients in whom all the ducts needed to be defined, the single-shot RARE technique was preferred to the multislice HASTE technique (p < .01).

CONCLUSION

The single-shot RARE technique shows fewer artifacts and is preferred to the multislice HASTE technique. However, both techniques show the same degree of sharpness of anatomic structures, both are able to reveal malignant diseases, and both provide enough information to determine a specific diagnosis.

Intestinal Behçet syndrome: CT features of patients with and patients without complications

PURPOSE

To analyze the computed tomographic (CT) features of intestinal Behçet syndrome and to determine the usefulness of CT in detecting complications.

MATERIALS AND METHODS

The CT scans of 28 patients with intestinal Behçet syndrome were retrospectively reviewed. Five patients had bowel perforation, and two had peritonitis. Patterns of bowel involvement, patterns of contrast enhancement, and ancillary findings were compared in patients with complications (n = 7) and patients without complications (n = 21).

RESULTS

Ten patients had polypoid lesions, nine had a thickened bowel wall, and nine had both findings. Lesion enhancement was mild in eight patients (29%) and marked in 20 (71%). Polypoid lesions were more commonly seen in patients without complications (P = .020); a thickened bowel wall was more commonly seen in patients with complications (P = .030). Seventeen of 18 patients (94%) with minimal perienteric infiltration did not have complications (P = .0003), whereas all five patients with severe perienteric infiltration did have complications.

CONCLUSION

In patients with known intestinal Behçet syndrome, CT can be useful in determining the extent of the lesions and in identifying cases in which complications are likely to occur.

Biliary stricture caused by blunt abdominal trauma: clinical and radiologic features in five patients

PURPOSE

To evaluate the clinical and radiologic features of biliary stricture after blunt abdominal trauma and to report the results of endoscopic stent placement.

MATERIALS AND METHODS

Medical records and radiologic findings were reviewed in five patients with biliary stricture after blunt abdominal trauma. The level, length, and contour of the strictures were analyzed with endoscopic retrograde cholangiopancreatography (ERCP). Computed tomographic (CT) scans were also reviewed to determine the presence of biliary dilatation, configuration of the injured bile duct, and ancillary abdominal findings. Results from endoscopic stent placement were evaluated in all patients.

RESULTS

Stricture occurred in the suprapancreatic portion of the common bile duct in four patients and in the intrapancreatic portion in one patient. At ERCP, the stricture contour was concentric and smooth in three patients, eccentric and smooth in one, and abruptly terminated in one. CT showed abrupt narrowing of the common bile duct with dilatation of the proximal portion in all patients. Endoscopic stent placement was successful in all patients.

CONCLUSION

Patients with biliary stricture after blunt abdominal trauma exhibit a delayed onset of symptoms. A correct diagnosis may be difficult on the basis of findings from CT or ERCP alone without a clinical history or evidence of contusions at other sites.

Use of methylcellulose in small bowel follow-through examination: comparison with conventional series in normal subjects

BACKGROUND

To evaluate and optimize a modified small bowel follow-through examination (SBFT) by using an oral administration of a large amount (600 mL) of methylcellulose after taking a small amount of barium.

METHODS

Ninety-nine normal subjects underwent modified SBFT with an oral administration of 600 mL of 0.5% methylcellulose after taking 100 mL of 120% or 100, 150, or 200 mL of 70% w/v barium. The transradiancy and distensibility of the bowel and the transit time were compared with those of 39 other normal subjects who underwent conventional SBFT with 500 mL of 70% w/v barium.

RESULTS

Except for two subjects who developed diarrhea immediately after examination, no patients complained of acute symptoms, such as abdominal pain or vomiting. Modified SBFT was much superior to conventional series for obtaining good bowel transradiancy and rapid transit time (range = 37-49 min), but bowel distention was not significantly improved. The use of 150 mL of 70% w/v barium was better than the other three modified techniques for achieving good bowel transradiancy, rapid transit time, and less occurrence of flocculation.

CONCLUSION

Modified SBFT is a simple method for easily improving the image quality in terms of bowel transradiancy and transit time.

Anatomical communications of the perirenal space

There are controversies over the anatomical communications between the perirenal space and the adjacent extraperitoneal spaces. Clinical studies, mainly based on CT, show fluid collections extending into the adjacent space; into the bare area of the liver on the right, into the superior extraperitoneal space on the left, towards the midline from each perirenal space, and into the lower retroperitoneal space of the abdomen and pelvis. There are certain constant anatomical barriers limiting free extension of fluid or pathology. The pattern of fluid collection in the perirenal space and extension into the adjacent extraperitoneal space is relatively consistent although it varies with the amount and nature of the pathological fluid collection. This pictorial review illustrates anatomical barriers and CT findings of perirenal fluid collections and their extension into adjacent extraperitoneal spaces.

US findings of xanthogranulomatous cholecystitis

The ultrasound (US) scans of eleven patients with histologically proven xanthogranulomatous cholecystitis have been reviewed. The thickness of the gallbladder (GB) wall, echogenicity of the thickened GB wall, the presence of intramural nodules, gallstones, pericholecystic fluid, loss of wall definition with the liver, and intrahepatic ductal dilatation were specifically assessed by two radiologists. The range of thickness of the GB wall was 3-20mm (mean, 11.2 mm). Thickening was diffuse in nine cases and focal in two. The thickened GB wall, excluding intramural nodules, was echogenic in seven, isoechoic in three and hypoechoic in one, compared with hepatic echogenicity. Intramural nodules were found in eight cases. These were discrete, oval or flat, and of low echogenicity. These ranged in size from 6 to 12 mm (mean, 10.5 mm). Gallstones were present in six cases and there was intrahepatic duct dilatation in two of these. Definition between the liver and the GB was obliterated in seven cases. One case of GB perforation, confirmed at operation, demonstrated pre-operatively a GB wall defect and connection with the surrounding pericholecystic fluid. Pericholecystic fluid was absent in the other 10 cases. Xanthogranulomatous cholecystitis presents ultrasonically as GB wall thickening, and the majority of cases in this series also demonstrated intramural hypoechoic nodules. These findings can be helpful in the diagnosis of xanthogranulomatous cholecystitis.

Lymphoepithelial cysts of the pancreas: CT and sonographic findings

Two cases of rare lymphoepithelial cyst (LEC) of the pancreas are presented. Although the histogenesis of this lesion is not known, it can be histologically differentiated from other pancreatic and retropancreatic cysts. The importance of its recognition is in the distinction from cystic neoplasm of the pancreas.

Application of MRI for small intestinal diseases

Until recently, MRI has not been considered to be suitable for the evaluation of the small intestine due to artifacts associated with bowel peristalsis or respiration. However, recent advances of MR techniques enable the acquisition of clear images of the small intestine. Therefore, the purpose of this article is to review the details for the application of MRI in patients with small intestinal diseases. This article discusses bowel preparation and oral contrast agents as well as MR techniques and pulse sequences. Thereafter, the usefulness of MRI for the lesions in the peritoneal cavity or in the gastrointestinal tract are discussed. Small intestinal lesions are categorized into inflammatory, neoplastic, ischemic, and obstructive bowel diseases. In conclusion, MRI can be used as an alternate modality of choice for imaging various diseases of the small intestine.

Vasculature in hepatocellular carcinoma after transcatheter arterial chemoembolization: comparison of power and color Doppler sonography

The purpose of this study was to compare power Doppler sonography with conventional color Doppler sonography for the detection of the vascularity of hepatocellular carcinomas after transcatheter arterial chemoembolization. Of the 93 embolized hepatocellular carcinomas, hypervascularity was demonstrated in 36 on angiography; power Doppler sonography correctly identified pulsatile flow signals in 33 (92%) of these 36, whereas color Doppler sonography identified flow signals in 24 (67%). A statistically significant difference was noted when the sizes of the nodules were 30 mm or less. Despite technical difficulties, such as flash artifact, power Doppler sonography is superior to color Doppler sonography for detection of hypervascularity, especially in small embolized nodules of hepatocellular carcinoma (30 mm or less in diameter).

Benign biliary strictures associated with recurrent pyogenic cholangitis: treatment with expandable metallic stents

OBJECTIVE

The purpose of this study was to determine the long-term effectiveness of expandable metallic stents in benign biliary strictures associated with recurrent pyogenic cholangitis and the differences in primary patency of the various types of stents deployed.

SUBJECTS AND METHODS

During a 20-month period, 26 metallic stents (19 Gianturco-Rosch Z stents and seven Strecker stents) were used to treat benign biliary strictures associated with recurrent pyogenic cholangitis in 23 patients (11 men and 12 women; mean age, 42 years; range, 30-78 years). Insertion routes were percutaneous transhepatic biliary drainage tracts for 16 stents, T-tube tracts for seven stents, and retrograde endoscopic routes for three stents. The deployed locations were common hepatic or common bile ducts for 11 stents, right or left hepatic ducts for 10 stents, and segmental ducts for five stents.

RESULTS

The initial technical success rate was 100%. Two stents in one patient migrated spontaneously. Primary stent patency for the remaining 24 stents was 34 months (range, 3-58 months). Primary stent patency of the Gianturco-Rosch Z and Strecker stents was 50 and 10 months, respectively (p < .05). Primary stent patency for the intrahepatic and extrahepatic ducts was 50 and 18 months, respectively (p = .05). Primary patency rates for all stents at 6, 12, 24, and 36 months were 92%, 75%, 67%, and 46%, respectively. The causes of stent obstruction were recurrent stone or sludge in eight stents and epithelial hyperplasia in five stents.

CONCLUSION

We believe that metallic stent placement is not an effective long-term treatment technique for benign biliary stricture associated with recurrent pyogenic cholangitis.

Differentiation of simple and strangulated small-bowel obstructions: usefulness of known CT criteria

PURPOSE

To evaluate the usefulness of known computed tomographic (CT) criteria for the differentiation of simple and strangulated small-bowel obstructions.

MATERIALS AND METHODS

CT scans of 84 patients with simple (n = 43) and strangulated (n = 41) small-bowel obstructions caused by adhesions, hernia, and volvulus were reviewed retrospectively. Diagnoses were made with surgery (n = 55) and during clinical follow-up (n = 29). CT criteria evaluated were configuration of obstructed bowel loop, target sign, bowel wall thickening and enhancement, changes in mesentery and mesenteric vasculature, and amount and attenuation of ascites.

RESULTS

CT findings that enabled the detection of strangulated obstructions were poor or no enhancement of bowel wall (sensitivity, 34%; specificity, 100%) and a serrated beak (sensitivity, 32%; specificity, 100%). When these two findings were excluded from analysis, a large amount of ascites, an unusual course of mesenteric vasculature, and diffuse engorgement of mesenteric vasculature were shown to be useful CT findings for performing multivariate regression analysis. Application of these five CT findings enabled identification of 35 (85%) of 41 patients with strangulated obstructions.

CONCLUSION

Detecting a combination of selected, known CT criteria increases the diagnostic accuracy of CT to enable differentiation of simple and strangulated small-bowel obstructions.

ERCP and CT findings of ectopic drainage of the common bile duct into the duodenal bulb

OBJECTIVE

The purpose of this study was to evaluate ERCP and CT findings of ectopic drainage of the common bile duct into the duodenal bulb.

CONCLUSION

Although rare, the diagnosis of ectopic drainage of the common bile duct into the duodenal bulb is important to prevent inadvertent damage during biliary tract or gastric surgery and to clarify the cause of chronic peptic ulcers.

Continuation of gas from the right perirenal space into the bare area of the liver

PURPOSE

It is difficult to explain some CT findings pertaining the anatomic relationship between the bare area of the liver and the right retroperitoneal space on the basis of the traditional three compartment concept of retroperitoneal anatomy. The purpose of this article is to ascertain and illustrate possible communication between the bare area of the liver and the right perirenal space in patients with gas-forming retroperitoneal infection.

METHOD

We reviewed CT findings in 24 cases with retroperitoneal gas-forming condition with particular emphasis on the extent of the infection and resultant distribution of gas.

RESULTS

CT images showed gas within the right perirenal space extended upward directly into the bare area of the liver in six cases.

CONCLUSION

The right perirenal space is considered open toward the bare area of the liver. Therefore, gas within the perirenal space may communicate directly with the bare area of the liver.

The value of pancreatoscopy in patients with mucinous ductal ectasia

We report here on three cases of mucinous ductal ectasia in which the diagnosis was suggested by abdominal computed tomography and finally established by duodenoscopy with pancreatoscopy. Duodenoscopic examination of the ampulla of Vater demonstrated a patulous papillary orifice and extrusion of viscid mucus. Pancreatoscopic examination was carried out in all three patients, and characteristic findings such as papillary or villous mucosal projections coated with whitish gelatinous mucus were noted. In patients with mucinous ductal ectasia in whom the radiographic findings are equivocal, pancreatoscopic examination may provide valuable information for the differential diagnosis of amorphous filling defects in the main pancreatic duct, and may provide information that helps to determine the extent of the pathology and the resection margin.

Gastrointestinal involvement in Henoch-Schönlein syndrome: CT findings

OBJECTIVE

The purpose of this study was to describe the CT features of gastrointestinal involvement in seven patients with Henoch-Schönlein syndrome.

CONCLUSION

Although the incidence of Henoch-Schönlein syndrome is low, it should be considered when CT scans show multifocal areas of bowel-wall thickening, mesenteric edema, vascular engorgement, and nonspecific lymphadenopathy. It should be considered especially in young patients with acute gastrointestinal symptoms.

Usefulness of CT in patients with ischemic colitis proximal to colonic cancer

OBJECTIVE

The purpose of this study was to assess the usefulness of CT scans for distinguishing ischemic from tumoral segments in patients with colonic carcinoma complicated by proximal bowel ischemia.

MATERIALS AND METHODS

CT scans of 20 patients with ischemic colitis proximal to obstructing colonic carcinoma were reviewed retrospectively. The concomitant presence of ischemia was proven on pathologic examinations in 12 patients and on barium enema studies in the remaining eight patients. CT scans were analyzed for the involved site and length, bowel wall thickness, enhancing pattern of both tumoral and ischemic segments, and changes in the pericolic space. The results of tumor staging on CT scans were compared with those of pathologic findings.

RESULTS

Distinction of ischemic from tumoral segments could be made on CT in 15 (75%) of the 20 patients. Of the 20 patients, 18 had ischemic segments contiguously proximal to the tumoral segment, and the remaining two patients had a skipped zone with intervening normal mucosa. Tumoral segments were irregularly thickened in most patients. Maximum thickness ranged from 0.8 to 4.5 cm (mean, 2.0 cm). Most often the ischemic segment was concentrically and smoothly thickened, ranging from 0.6 to 1.5 cm (mean, 1.0 cm). The tumoral segments enhanced heterogeneously in 12 patients and enhanced homogeneously in the remaining eight, whereas ischemic segments enhanced homogeneously in 14 (70%) patients and heterogeneously in six. On CT scans, we saw the target or double halo sign in four (20%) patients. Pericolic vascular engorgement was 19 patients, two of whom were overstaged because pericolic vascular engorgement was interpreted as tumor infiltration.

CONCLUSION

Although CT findings are not specific for certain groups of patients, they are often helpful in distinguishing tumoral from ischemic segments in patients with ischemic colitis proximal to colonic carcinoma. An understanding of this pathologic entity may increase the accuracy of CT for staging colonic carcinoma.