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

Imaging of intestinal vasculitis focusing on MR and CT enterography: a two-way street between radiologic findings and clinical data

Diagnosis of intestinal vasculitis is often challenging due to the non-specific clinical and imaging findings. Vasculitides with gastrointestinal (GI) manifestations are rare, but their diagnosis holds immense significance as late or missed recognition can result in high mortality rates. Given the resemblance of radiologic findings with some other entities, GI vasculitis is often overlooked on small bowel studies done using computed tomography/magnetic resonance enterography (CTE/MRE). Hereon, we reviewed radiologic findings of vasculitis with gastrointestinal involvement on CTE and MRE. The variety of findings on MRE/CTE depend upon the size of the involved vessels. Signs of intestinal ischemia, e.g., mural thickening, submucosal edema, mural hyperenhancement, and restricted diffusion on diffusion-weighted imaging, are common in intestinal vasculitis. Involvement of the abdominal aorta and the major visceral arteries is presented as concentric mural thickening, transmural calcification, luminal stenosis, occlusion, aneurysmal changes, and collateral vessels. Such findings can be observed particularly in large- and medium-vessel vasculitis. The presence of extra-intestinal findings, including within the liver, kidneys, or spleen in the form of focal areas of infarction or heterogeneous enhancement due to microvascular involvement, can be another radiologic clue in diagnosis of vasculitis. The link between the clinical/laboratory findings and MRE/CTE abnormalities needs to be corresponded when it comes to the diagnosis of intestinal vasculitis.

SMALL BOWEL IS LARGELY AFFECTED IN BEHÇET’S DISEASE: A LONG-TERM FOLLOW-UP OF GASTROINTESTINAL SYMPTOMS

ABSTRACT Background Behçet’s disease is a rare immune-mediated disorder that can affect the gastrointestinal tract. The prevalence and extension of small bowel involvement is largely unknown. Objective The aim of this study was to describe the small bowel lesions diagnosed by double-balloon enteroscopy (DBE) and to verify if these findings were associated to the presence of gastrointestinal symptoms and disease activity after long-term follow-up. Methods This study included 19 Behçet’s disease patients who underwent DBE. After a mean follow-up of 15 years the endoscopic findings were associated to the presence of gastrointestinal symptoms, disease activity and current therapy through collection of electronic medical records. Results A total of 63.2% patients were female and the mean age was 37 years at the time of DBE. Mean disease duration at baseline was 24 years. 11 patients had no gastrointestinal symptoms and eight patients presented either abdominal pain, gastrointestinal bleeding or diarrhea. The average procedure time was 1 hour and 30 minutes and the ileum was achieved in all patients but one. Small bowel ulcers were diagnosed in 78.9%, with 63.1% of jejunal involvement. Two patients presented only small bowel edema and two were normal by DBE. Eight patients had concomitant gastric ulcers. Gastrointestinal symptoms prior to DBE were present in 36.8% of the patients and, after follow-up, all of them persisted with some of the symptoms. Bleeding was reported by three patients at baseline and persisted in only one patient. The frequency of treatment with steroids and immunomodulators was 31.6% and 57.9% at baseline, respectively, and 21% in both at the end of the follow-up. No patient was treated with biologics at the time of the DBE procedure and the current rate of biologic use is 21%. Conclusion Small bowel involvement in Behçet’s disease was frequently demonstrated by DBE even in asymptomatic patients. Understanding clinical evolution of the disease over the years and the impact of such diagnosis still represents a challenge, possibly with the need for novel treatment.

Involvement of small bowel in systemic disease: CT and MR imaging finding

Computerized tomography (CT) and magnetic resonance imaging (MRI), particularly MR Enterography, are the standard cross-sectional imaging modalities used to study small bowel involvement in a context of multiorgan disease. Clinical symptoms are generally nonspecific in such cases. Moreover, imaging findings of the different conditions often overlap. However, analysis of the location, distribution of the lesions on the small bowel wall, as well as of the rest of the bowel and of distant organs, may help narrow the spectrum of diagnoses of multiorgan conditions involving both the small bowel and other organs. The purpose of this presentation is to review and illustrate the CT and MRI features of small bowel involvement in systemic disease. Based on the underlying mechanism, we will categorize them as follows: congenital/hereditary, immunologic, infiltrative, vascular, infectious and miscellaneous.

Ileocecal thickening: Clinical approach to a common problem

Ileocecal thickening (ICT) is a common finding on radiological imaging. It can be caused by a variety of inflammatory, infectious, or neoplastic conditions, and evaluating a patient of ICT can be a challenging task. Intestinal tuberculosis (ITB), Crohn's disease (CD), and adenocarcinoma are the most common causes. Enteric bacterial infections, cytomegalovirus, histoplasmosis, amebiasis, systemic vasculitis, lymphoma, etc. should be suspected in appropriate clinical settings. However, it could often be a spurious or nonspecific finding. A thickness of more than 3 mm in a normally distended small bowel is usually considered abnormal. Detailed evaluation of imaging of the site and extent of thickening; the degree and pattern of thickening; and the associated findings, such as degree of fat stranding, fibrofatty proliferation, adjacent lymph nodes, and solid organ involvement, should be performed. Ileocolonoscopy is an important tool for diagnosing and obtaining samples for tissue diagnosis. Histopathology is usually the gold standard for diagnosis, although—not uncommonly—findings could be nonspecific, and reaching a definitive diagnosis is difficult. As such, a systematic approach with the integration of clinical, biochemical, radiological, endoscopic, histological, and other laboratory tests is the key to reaching a diagnosis. In this article, we review the causes of ICT and present a clinical approach for the management of ICT.

Surgical treatment of intestinal perforation in Behçet Syndrome: an unusual presentation

Behçet syndrome is a chronic, recurring, systemic disorder characterized by the histopathologic finding of nonspecific vasculitis in multiple organs. Behçet syndrome involves the gastrointestinal tract in 10-50% of patients; The main sites of involvement are the terminal ileum and cecum. In patients with Behçet syndrome, CT is advocated for early detection of complications as well as for exclusion of other abdominal pathologic conditions but there is no specific exam. The report of histology in conjunction with the clinical history and the presence of oral ulcers, uveitis and suspected cutaneous lesions suggests the diagnosis. The optimal medical treatment of Behçet syndrome has not yet been well established. In rare cases surgery must be required to control the disease. The authors report one case of Behcet Syndrome presenting with intestinal perforation.

Magnetic Resonance Enterography Findings of Intestinal Behçet Disease in a Child

Behçet's disease (BD) is a multisystem disorder of unknown aetiology, characterized by recurrent oral ulcers, genital ulcers, uveitis, skin lesions, and pathergy. Gastrointestinal disease outside the oral cavity is well recognized and usually takes the form of small intestinal ulcers, with the most significant lesions frequently occurring in the ileocaecal region. Symptoms usually include nausea, vomiting, colicky abdominal pain, and change in bowel habit and it is not unusual that patients may present late, with life-threatening complications requiring surgery. Diagnosis has been hindered for many years by limitations in imaging the small bowel and it is usually achieved by means of endoscopy and CT of the abdomen. Magnetic resonance enterography (MRE) is a relatively new technique, which has a high diagnostic rate in patients with Crohn's disease (CD). Although many similarities between CD and intestinal BD have already been described in literature, the role of MRE in the evaluation of intestinal BD has never been defined up to now. We report a case of a 12-year-old female patient with diagnosis of BD who presented at our institution for recurrent colicky abdominal pain and diarrhoea. The patient underwent MRE that demonstrated the gastrointestinal involvement.

Endoscopic findings of gastrointestinal involvement in Chinese patients with Behcet’s disease

AIM: To report the incidence, clinical features and outcomes of gastrointestinal (GI) involvement in Behcet’s disease (BD).

METHODS: A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopies were performed in 148 patients. Four hundred age- and sex-matched controls were enrolled for comparison.

RESULTS: Fifty-two (35.1%) patients had GI lesions. After a mean follow-up of 10 mo, ileocecal ulcers had been confirmed in 20 patients, including active ulcer(s) in 18 patients, but no ileocecal ulceration was found in controls. GI symptoms were present in 14 patients with active ulcer(s), while 4 patients with smaller ulcer were asymptomatic. Endoscopic features of ileocecal ulcer were: a single ulcer (50%), larger than 1 cm in diameter (72.2%), and round/oval or volcano-type in shape (83.3%). Compared with patients without GI involvement, less ocular lesions, lower levels of albumin, erythrocyte count and hemoglobin, and higher levels of C-reactive protein and erythrocyte sedimentation rate were confirmed in the intestinal BD group. Four patients had esophageal ulcers in the BD group but no case in controls. The other endoscopic findings were similar between the two groups. The prevalence of Helicobacter pylori infection was similar in both groups. Most patients received an immunomodulator and responded well.

CONCLUSION: GI lesions commonly occur in Chinese BD patients. The most frequently involved area is the ileocecal region. Esophageal ulcer might be a rare but unique lesion.

Computed tomography enterography for evaluation of inflammatory bowel disease

Computed tomography enterography (CTE) has become a main modality for the evaluation of inflammatory bowel disease (IBD). It simultaneously offers visualization of the small bowel and extraintestinal status, which is helpful for diagnosing IBD. Crohn disease has long segmental enhancing wall thickening related with the eccentric longitudinal distribution. In addition, mural stratification, fibrofatty proliferation, positive comb sign by increased mesenteric vascularity and internal/perianal fistula are characteristics of Crohn disease and can be identified on CTE. Short segmental inflammatory wall thickening and the central low attenuated lymph nodes are favorable CT finding of intestinal tuberculosis. A geographic, relatively large, and deep penetrating ulcer with bowel wall thickening and mural hyperenhancement in ileocecal area are characteristics of intestinal Behcet disease. Each of CTE findings for the IBDs is helpful for differential diagnosis. The main disadvantage of this technique is the requisite radiation exposure of patients, particularly in young patients. However, recent development of advanced CT techniques is promising for radiation dose reduction without compromising diagnostic image quality.

Adamantiades-Behcet's disease-complicated gastroenteropathy

Adamantiades-Behcet’s disease (ABD) is a chronic, relapsing, systemic vasculitis of unknown etiology. It is more prevalent in populations along the ancient Silk Road from Eastern Asia to the Mediterranean Basin, and most frequently affects young adults between the second and fourth decades of life. ABD-complicated gastroenteropathy is a significant cause of morbidity and mortality, with abdominal pain as the most common symptom. The ileocecal region is affected predominantly, with ulcerations that may lead to penetration and/or perforation, whereas other parts of the gastrointestinal system including the esophagus and stomach can also be affected. Endoscopy is useful to locate the site and extent of the lesions, and tissue biopsy is often warranted to examine the histopathology that is often suggestive of underlying vasculitis of small veins/venules or, alternatively in some cases, nonspecific inflammation. Bowel wall thickening is the most common finding on computed tomography scan. Treatment is largely empirical since well-controlled studies are difficult to conduct due to the heterogeneity of the disease, and the unpredictable course with exacerbation and remission. Corticosteroids with or without other immunosuppressive drugs, such as cyclophosphamide, azathioprine, sulfasalazine, tumor necrosis factor α antagonist or thalidomide should be applied before surgery, except in emergency.

Gastrointestinal manifestations of Behçet's disease

Behçet's disease is a rare vasculitis diagnosed by the presence of recurrent oral ulcers and two of the following: genital ulcers, typical eye lesions, typical skin lesions, and positive pathergy test. It is most commonly seen in countries along the ancient silk road from Eastern Asia to the Mediterranean Basin. Young adults between the second and fourth decades of life are mainly affected, with abdominal pain being the most common symptom. The ileocecal region is most commonly affected, with ulcerations that may penetrate or perforate. Rarely, the esophagus and stomach may have ulcerations. Bowel wall thickening is the most common finding on computed tomography (CT) scan. Pathology shows a vasculitis mainly involving the small veins or, alternatively, nonspecific inflammation. Corticosteroids, with or without other immunosuppressive drugs, are used for severe eye disease. Their use in intestinal disease is largely empirical. Surgery may be required for perforation. Behçet's disease runs a chronic, unpredictable course with exacerbations and remissions which decrease in frequency and severity over time. Death is mainly due to major vessel disease and neurological involvement.

Colonic perforation in Behçet’s syndrome

A 17-year-old gentleman was admitted to our hospital for headache, the differential diagnosis of which included Behçet’s syndrome (BS). He developed an acute abdomen and was found to have air under the diaphragm on erect chest X-ray. Subsequent laparotomy revealed multiple perforations throughout the colon. This report describes an unusual complication of Behcets syndrome occurring at the time of presentation and a review of the current literature of reported cases.

Radiologic and clinical findings of Behçet disease: comprehensive review of multisystemic involvement

Behçet disease is a chronic, relapsing, systemic disorder of unknown etiology, characterized by recurrent oral and genital ulcers, uveitis, and other clinical manifestations in multiple organ systems. Although the diagnosis is made on the basis of the combination of typical clinical symptoms, radiologic findings of Behçet disease show characteristic features of its involvement in the gastrointestinal, neurologic, cardiovascular, and thoracic organ systems. In the gastrointestinal tract, Behçet disease may produce various types of ulcers in the esophagus, stomach, and small and large intestines, as well as deeply penetrating ulcerations in the ileocecal region, with frequently accompanying enteric fistulas. Neurologic involvement includes typical and atypical parenchymal neurobehcet disease, dural sinus thrombosis, cerebral arterial aneurysm, occlusion, dissection, and meningitis. Vascular involvement is divided into three subsets including venous occlusion, arterial occlusion, and arterial aneurysm. Cardiac manifestations include intracardiac thrombus, endomyocardial fibrosis, periaortic pseudoaneurysm, and rupture of the sinus of Valsalva. Manifestations of Behçet disease in the thorax include pulmonary arterial aneurysm, pulmonary arterial thromboembolism, thrombosis in the superior vena cava, pulmonary infarction, hemorrhage, and vasculitis of the pleura and pericardium. These various manifestations of Behçet disease respond to steroid treatment; however, one of the characteristics of Behçet disease is the high rate of complications and recurrence after surgery. Familiarity with its various radiologic and clinical characteristics is essential in making an accurate early diagnosis and for prompt treatment of patients with Behçet disease.

Multidetector CT angiography in the diagnosis of mesenteric ischemia

Multidetector CT is an ideal tool for the diagnosis of acute and chronic mesenteric ischemia. Advanced CT scanners and expertise in three-dimensional imaging are becoming increasingly widespread, opening the door to new opportunities and challenges in the evaluation of patients suspected of having mesenteric ischemia. This article reviews contrast administration and image acquisition protocols, the anatomy of the mesenteric vasculature, the etiology of acute and chronic mesenteric ischemia, and CT findings diagnostic for these conditions.

Anti-Saccharomyces cerevisiae antibody in intestinal Behçet's disease patients: relation to clinical course

PURPOSE

This study was designed to assess anti-Saccharomyces cerevisiae antibody positive rate in Behçet's disease and intestinal Behçet's disease and to evaluate whether anti-Saccharomyces cerevisiae antibody expression is associated with clinical findings at diagnosis and clinical course of intestinal Behçet's disease.

METHODS

One hundred six patients with intestinal Behçet's disease, 30 patients with Behçet's disease, and 45 healthy control subjects were included. Anti-Saccharomyces cerevisiae antibody was detected by indirect immunofluorescence assay. According to anti-Saccharomyces cerevisiae antibody expression, the various parameters at diagnosis, cumulative relapse rates, and cumulative probabilities of operation were analyzed.

RESULTS

Anti-Saccharomyces cerevisiae antibody positive rate was 44.3 percent in intestinal Behçet's disease, 3.3 percent in Behçet's disease, and 8.8 percent in healthy control subjects. In patients with intestinal Behçet's disease, age, gender, distribution of Behçet's disease subtype, symptoms, laboratory tests, and colonoscopic findings at diagnosis were not different according to anti-Saccharomyces cerevisiae antibody expression. Cumulative probability of a first operation was significantly higher in anti-Saccharomyces cerevisiae antibody (+) intestinal Behçet's disease than in anti-Saccharomyces cerevisiae antibody (-) intestinal Behçet's disease: 44.8 and 17.2 percent at one year, and 53 and 24.3 percent at two years after diagnosis, respectively (P=0.006). The number of patients who underwent two or more operations was higher in anti-Saccharomyces cerevisiae antibody (+) intestinal Behçet's disease than in anti-Saccharomyces cerevisiae antibody (-) intestinal Behçet's disease (21.3 vs. 8.5 percent). The cumulative relapse rates were not different between the two groups.

CONCLUSIONS

Anti-Saccharomyces cerevisiae antibody positive rate was 44.3 percent in intestinal Behçet's disease. Clinical findings at diagnosis and cumulative relapse rates of intestinal Behçet's disease were not found to be associated with anti-Saccharomyces cerevisiae antibody expression. However, patients with anti-Saccharomyces cerevisiae antibody (+) intestinal Behçet's disease were more likely to receive surgical treatment.

Single or multiple perforations with varying locations as a complication of intestinal Behçet's disease: report of three cases

Intestinal ulcers in Behçet's disease (BD) tend to cause perforation with significant morbidity. The optimal surgical procedure in such cases is controversial and the postoperative period can be eventful with an unpredictable course. We report three cases of perforations with varying locations in three patients with long-standing Behçet's disease. Two patients required two and one patient required four operations. It is emphasized that the clinician must be alert in a patient with BD when abdominal symptoms accompany the clinical picture. As soon as the diagnosis is reached, surgical intervention with limited resection must be performed. Endoscopic examination and careful medication play major roles in the follow-up.

Metastatic Colorectal Carcinoma: Cost-effectiveness of Percutaneous Radiofrequency Ablation versus That of Hepatic Resection

PURPOSE

To evaluate the relative cost-effectiveness of radiofrequency (RF) ablation and hepatic resection in patients with metachronous liver metastases from colorectal carcinoma (CRC) and compare the outcomes, cost, and cost-effectiveness of a variety of treatment and follow-up strategies.

MATERIALS AND METHODS

A state-transition decision model for evaluating the (societal) cost-effectiveness of RF ablation and hepatic resection in patients with CRC liver metastases was developed. The model tracks the presence, number, size, location, growth, detection, and removal of up to 15 individual metastases in each patient. Survival, quality of life, and cost are predicted on the basis of disease extent. Imaging, ablation, and resection affect outcomes through detection and elimination of individual metastases. Several patient care strategies were developed and compared on the basis of cost, effectiveness, and incremental cost-effectiveness (expressed as dollars per quality-adjusted life-year [QALY]). Extensive sensitivity analysis was performed to evaluate the impact of alternative scenarios and assumptions on results.

RESULTS

A strategy permitting ablation of up to five metastases with computed tomographic (CT) follow-up every 4 months resulted in a gain of 0.65 QALYs relative to a no-treat strategy, at an incremental cost of $2400 per QALY. Compared with this ablation strategy, a strategy permitting resection of up to four metastases, one repeat resection, and CT follow-up every 6 months resulted in an additional gain of 0.76 QALYs at an incremental cost of $24 300 per QALY. Across a range of model assumptions, more aggressive treatment strategies (ie, ablation or resection of more metastases, treatment of recurrent metastases, more frequent follow-up imaging) were superior to less aggressive strategies and had incremental cost-effectiveness ratios of less than $35 000 per QALY. Findings were insensitive to changes in most model parameters; however, results were somewhat sensitive to changes in size thresholds for RF ablation, the number of metastases present, and surgery and treatment costs.

CONCLUSION

RF ablation is a cost-effective treatment option for patients with CRC liver metastases. However, in most scenarios, hepatic resection is more effective (in terms of QALYs gained) than RF ablation and has an incremental cost-effectiveness ratio of less than $35 000 per QALY.

Percutaneous radiofrequency ablation of liver metastases in potential candidates for resection: the "test-of-time approach"

BACKGROUND

Some surgeons have advocated delaying resection of liver metastases to allow additional metastases which may be present, but are undetected, to be identified. This "test-of-time" approach can limit the number of resections performed on patients who ultimately will develop additional metastases. The current study evaluated the potential role and possible advantages of performing radiofrequency (RF) ablation during the interval between diagnosis and hepatic metastasectomy as part of a test-of-time management approach.

METHODS

Eighty-eight consecutive patients with 134 colorectal carcinoma liver metastases were potential candidates for hepatic metastasectomy. They were treated with percutaneous RF ablation using single (101 treatments) or triple-probe cluster (22 treatments) 18-gauge internally cooled electrodes. Treatment was performed under conscious sedation (22 of 119 treatments), anesthesia (14 of 119 treatments), or general anesthesia (83 of 119 treatments). At the time of the initial RF ablation procedure, 49 of 88 patients (56%) were found to have 1 metastasis, 32 of 88 patients (36%) had 2 metastases, and 7 of 88 patients (8%) had 3 metastases. Metastases ranged from 0.6 to 4.0 cm in greatest dimension (mean, 2.1 cm). Follow-up with serial computed tomography scans scans ranged from 18 to 75 months (median, 33 months) after the initial RF ablation.

RESULTS

A total of 119 RF ablations were performed. Complete necrosis was obtained in 53 of 88 patients (60%) and in 85 of 134 lesions (63%). During follow-up of these 53 patients, 16 (30%) remained free of disease and 37 (70%) developed new lesions. New lesions were intrahepatic in 26 of 37 patients (70%), extrahepatic in 4 patients (11%), and both intrahepatic and extrahepatic in 7 patients (19%). Of 26 patients whose new lesions were intrahepatic only, 15 (58%) were retreated with RF and 7 were free of disease at the time of last follow-up (median follow-up, 28 months). Ten additional patients with only intrahepatic new lesions were deemed untreatable and 1 patient underwent resection. Overall, among the 53 patients in whom complete tumor necrosis was achieved after RF ablation therapy, 52 (98%) were spared surgical resection: 23 (44%) because they have remained free of disease and 29 (56%) because they developed disease progression. Among all 88 patients, 21 (24%) underwent resection after RF ablation (8 were free of disease at the time of last follow-up), 23 (26%) remained free of disease after successful RF ablation, and 56 (64%) developed untreatable disease progression (44 after RF alone, 12 after RF and surgery). Lesions in 35 of 88 patients (40%) demonstrated local tumor recurrence on follow-up imaging studies. Twenty of these 35 patients (57%) underwent surgical resection, whereas the remaining 15 patients (43%) developed additional, untreatable metastases. New lesions were intrahepatic in 9 of 15 patients (60%), extrahepatic in 1 of 15 patients (7%), and both intrahepatic and extrahepatic in 5 of 15 patients (33%). No patient who had been treated with RF ablation became unresectable due to the growth of metastases and there was no evidence of needle track seeding in any patient after RF ablation. Overall, among the 35 patients in whom complete tumor necrosis was not achieved after RF ablation therapy, 15 (43%) were spared surgical resection.

CONCLUSIONS

The results of the current study suggest that current RF ablation techniques, when used as part of a test-of-time management approach, can decrease the number of resections performed. The approach results in complete tumor necrosis in some patients and provide an interval for others who ultimately will develop new intrahepatic and/or extrahepatic metastases to do so.

Colonoscopic findings in intestinal Behçet's disease

The aims of this study were to investigate the clinical and colonoscopic characteristics of patients with intestinal Behçet's disease and to compare the findings of typical and atypical intestinal Behçet's disease. Ninety-four patients diagnosed as having intestinal Behçet's disease were included. Of these, we considered 42 patients as having complete or incomplete type; these fulfilled the international criteria as "typical," and the other 52 patients were classified as having "atypical" intestinal Behçet's disease. Abdominal pain was the most common symptom (92%), followed by diarrhea and gastrointestinal bleeding. All of the 22 patients with a history of surgery had ulcers at the anastomotic site. Most of the patients, who had never been operated on, had lesions in the ileocecal area (96%). Sixty-three patients (67%) had a single ulcer. Many (76%) of the ulcers were larger than 1 cm, and the mean size of the ulcers was 2.9 cm. Most (99%) of the ulcers were round/oval or geographic in shape. Usually ulcers were deep (62%), and their margins discrete (80%). There was no difference in the endoscopic findings of typical and atypical intestinal Behçet's disease. Typical colonoscopic findings in intestinal Behçet's disease were single or a few deep ulcers with discrete margins in the ileocecal area or anastomotic site. Endoscopic characteristics of patients with intestinal involvement in the case of "suspect" or "possible" type of Behçet's disease that lack the systemic manifestations of Behçet's disease were in accord with those in "complete" or "incomplete" types of Behçet's disease, who fulfill the International Study Group for Behçet's Disease criteria.

Percutaneous tumor ablation: increased necrosis with combined radio-frequency ablation and intratumoral doxorubicin injection in a rat breast tumor model

PURPOSE

To determine whether a combination of intratumoral doxorubicin injection and radio-frequency (RF) ablation increases tumor destruction compared with RF ablation alone in an animal tumor model.

MATERIALS AND METHODS

R3230 mammary adenocarcinoma 1.2-1.5-cm- diameter nodules (n = 110) were implanted subcutaneously in 84 female Fischer rats. For initial experiments (n = 46), tumors were treated with (a) conventional, monopolar RF (250 mA +/- 25 [SD] at 70 degrees C +/- 1 for 5 minutes) ablation alone; (b) direct intratumoral doxorubicin injection (volume, 250 microL; total dose, 0.5 mg) alone; (c) combined therapy (doxorubicin injection immediately followed by RF ablation); (d) RF ablation and injection of 250 microL of distilled water; or (e) no treatment. In subsequent experiments, amount of doxorubicin (0.02-2.50 mg; n = 40 additional tumors) and timing of doxorubicin administration (2 days before to 2 days after RF ablation; n = 24 more tumors) were varied. Pathologic examination, including staining for mitochondrial enzyme activity and perfusion, was performed, and the resultant tumor destruction from each treatment was evaluated.

RESULTS

Coagulation diameter was 6.7 mm +/- 0.6 for tumors treated with RF ablation alone and 6.9 mm +/- 0.7 for those treated with RF ablation and water (P =.52), while intratumoral doxorubicin injection alone produced only 2.0-3.0 mm of coagulation (P <.001). Increased coagulation was observed only with combined doxorubicin injection and RF therapy (P <.001). Coagulation was dependent on concentration and timing of doxorubicin administration, with greatest coagulation (11.5 mm +/- 1.1) observed for doxorubicin administered within 30 minutes of RF ablation.

CONCLUSION

Adjuvant intratumoral doxorubicin injection increases coagulation in solid tumors compared with RF ablation alone. Increased tumor destruction is also seen when doxorubicin is administered after RF ablation, which suggests that RF ablation may sensitize tumors to chemotherapy. Such combination therapies may, therefore, offer improved methods for ablating solid tumors.

Radiologic findings of Behçet syndrome involving the gastrointestinal tract

Behçet syndrome is characterized by the histopathologic finding of nonspecific vasculitis in multiple organs. The diagnosis is usually made on the basis of the combination of clinical signs and symptoms. This disease involves the gastrointestinal tract in 10%-50% of patients, and the terminal ileum and cecum are chiefly affected. Barium study is useful in demonstrating the characteristic radiographic features of Behçet syndrome involving the gastrointestinal tract. The presence of deep, penetrating ulcers results in a high rate of complications, such as perforation, fistula, hemorrhage, and peritonitis. Furthermore, recurrence of disease adjacent to or at the surgical anastomosis is common. Computed tomography is useful in determining the extent of the lesions and in identifying cases in which complications are likely to occur. Familiarity with the various radiologic findings of Behçet syndrome involving the gastrointestinal tract helps in making an early diagnosis, as well as in establishing an appropriate treatment strategy.

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.

Histopathological correlation to MRI findings during and after laser-induced thermotherapy in a pig pancreas model

RATIONALE AND OBJECTIVES

To investigate whether percutaneous laser-induced thermotherapy (LITT) with continuous magnetic resonance (MR) monitoring of thermal effects within the pancreas is feasible in a porcine model.

METHODS

Laser applicators were placed in the pancreas of 15 female pigs. A temperature-sensitive (thermo--fast low-angle shot) sequence was used for continuous monitoring of thermal effects during LITT at 1.5 T. Follow-up MR images were acquired, the pigs were observed for 7 days, and then a pathological examination was performed after sacrifice.

RESULTS

Continuous MR monitoring visualized thermal effects in pancreatic tissue and thermal damage of the spleen (n = 1), the left kidney (n = 1), and peripancreatic fat (n = 4) but missed the thermal damage of the duodenum (n = 2). Thermal-induced lesions (10--32-mm diameter) were clearly visualized on contrast-enhanced T1-weighted images.

CONCLUSIONS

Laser-induced thermotherapy of pancreatic tissue was feasible in this porcine model, and online monitoring was practicable. Further studies are necessary to increase the accuracy of online MR imaging of thermal effects.

[Value of abdominal-pelvic computed tomography in adult rheumatoid purpura]

PURPOSE

Henoch-Schonlein purpura is a rare eventuality in adulthood. Abdominal involvement can worsen the short-term prognosis and justify medical treatment to avoid surgery.

METHODS

Abdominopelvic computed tomography (CT) was performed in six adult patients (four men and two women; age range, 19-74 years) with Henoch-Schonlein purpura before any treatment. Abdominal symptoms were concomitant with the purpuric rash in two cases and followed it in the other cases.

RESULTS

The small bowel was always involved with a parietal thickening, and the target sign was observed in three patients. The lesions were located in the duodenum in two patients, the jejunum in two and the ileum in five. Two segments were involved in one patient and three segments in another patient. A peritoneal effusion was always present. No colonic lesion was discovered on CT. Once the results were known, all patients received steroids with initially intravenous methylprednisolone in five patients at doses ranging from 80 to 1,000 mg/day. On follow-up, none of the patients underwent surgery.

CONCLUSION

Abdominopelvic CT scan demonstrated signs suggestive of intestinal vasculitis. An underlying neoplasia or an eventual other cause of abdominal pain were explored and a steroid therapy was then began with a good outcome. Abdominal CT can be helpful in the diagnosis of abdominal involvement in Henoch-Schonlein purpura.

Percutaneous tumor ablation: increased coagulation by combining radio-frequency ablation and ethanol instillation in a rat breast tumor model

PURPOSE

To determine if percutaneously applied radio frequency (RF) combined with percutaneous ethanol instillation (PEI) can increase the extent of ablation in rat breast tumors.

MATERIALS AND METHODS

R3230 mammary adenocarcinoma was implanted bilaterally in the mammary fat pads of 18 female rats. The tumor nodules measured 1. 2-1.5 cm. Eight tumors each were treated with (a) conventional, monopolar RF (96 mA +/- 28; 70 degrees C for 5 minutes); (b) PEI (250 microL of ethanol infused over 1 minute); (c) combined therapy of PEI immediately followed by RF ablation; or (d) combined therapy of RF ablation immediately followed by PEI. Four tumors were not treated and served as controls. Histopathologic examination included staining for mitochondrial enzyme activity. Resultant coagulation necrosis was compared between treatment groups.

RESULTS

Coagulation necrosis was observed only within treated tumors. Tumors treated with RF alone had 6.7 mm +/- 0.6 of coagulation surrounding the electrode, and those treated with PEI alone had 6.4 mm +/- 0.6 of coagulation around the instillation needle (not significant). Significantly increased coagulation of 10.1 mm +/- 0.9 (P: <.001) was observed with the combined therapy of PEI followed by RF. RF followed by PEI did not increase coagulation (6.4 mm +/- 0.8 around the needle; not significant).

CONCLUSION

PEI followed by RF ablation therapy increases the extent of induced coagulation necrosis in rat breast tumors, as compared with either therapy alone.

CT of patients with right-sided colon cancer and distal ileal thickening

OBJECTIVE

The purpose of this study was to analyze the incidence and primary causes of distal ileal wall thickening in 131 patients with right-sided colon cancer.

SUBJECTS AND METHODS

During a 2-year period, 131 patients underwent surgical resection for right-sided colon cancer. Of these patients, we analyzed 13 who had distal ileal wall thickening on CT before surgery and also had the cause determined at pathology. CT findings were analyzed with regard to the morphologic features of colonic tumors, bowel wall involvement patterns of the distal ileum, and changes in the pericolic space.

RESULTS

Distal ileal wall thickening occurred in 13 (10%) of the 131 patients who had right-sided colon cancer. Three patients had polypoid colon cancer, whereas the other 10 had infiltrative colon cancer. The mean thickness of the involved colonic segments was 1.6 cm (range, 1.0-2.2 cm) with a mean length of 5.2 cm (range, 2.5-10.0 cm). Pericolic infiltration was mild in six patients and moderate in four patients. The mean length and thickness of the affected ileal segments were 3.2 cm (range, 1.5-6.0 cm) and 1.1 cm (range, 0.7-2.0 cm), respectively. On histopathologic examination, neoplastic processes involved the distal ileum in nine (69%) of the 13 patients. This involvement was caused by either direct tumor invasion in seven patients or lymphatic spread in two. In four patients (31%), nonneoplastic processes with edema and congestion involved the distal ileum.

CONCLUSION

The distal ileum may be abnormally thickened in about 10% of patients with right-sided colon cancer; this thickening results from tumor extension (69%) or a nontumorous process (31%).

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.

Sonographic appearances of conglomerated polyps (giant polyposis) in patients with Crohn's disease

Giant polyposis is a rare presentation of Crohn's disease (CD) of the colon and can be misdiagnosed as colon cancer. To our knowledge, the sonographic characteristics of conglomerated polyps in colonic CD have not been published. The purpose of this article is to describe sonographic findings in 3 patients with giant polyposis and evaluate the contribution of sonography in establishing this diagnosis. We conclude that sonography can facilitate the diagnosis of giant polyposis in CD by demonstrating associated findings in the large and small bowels that are suggestive of CD.

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.