Ultrasonography and computed tomography of inflammatory abdominal wall lesions

Twenty-four patients with inflammatory lesions of the abdominal wall were examined by ultrasonography. Nine of these patients underwent computed tomographic (CT) scanning as well. Both ultrasonography and CT clearly delineated the exact location and extent of abdominal wall abscesses. Abscesses were easily differentiated from cellulitis or phlegmon with ultrasound. The peritoneal line was more clearly delineated on ultrasonograms than on CT scans; abscesses were also more distinct on the ultrasonograms because of their low echogenicity compared with the surrounding structures. Gas bubbles, fat density with specific low attenuation values, and underlying inflamed bowel loops in obese patients with Crohn's disease were better delineated by CT.     

Computed tomography of the gallbladder.

Computed tomography (CT) was used to study 79 patients with suspected gallbladder disease. First and second generation scanners were used to determine the efficacy of CT in detecting cholecystitis or cholelithiasis. Manifestations of gallbladder disease such as hydrops, opaque and nonopaque gallstones, chronic cholecystitis with thickened inflammatory walls, and secondary liver abscesses can be easily detected. It is a useful technique for individuals in whom the gallbladder has failed to opacity on oral cholecystography. The scanning method is described, and estimates of reliability are given including its accuracy, limitations, and place in the management of gallbladder disease, especially cholelithiasis. When conventional radiographic examinations or ultrasound fail to give definitive diagnostic information, CT can be a useful alternative with an overall diagnostic accuracy greater than 80%.     

Indium-111 tropolonate leucocyte scanning in the detection of intra-abdominal abscesses

Indium-111 leucocyte scanning is established as an accurate method for localising intra-abdominal abscesses. With the currently available cell labelling techniques there is a variable and significant delay in localisation of abscesses which is a major disadvantage in comparison with ultrasound or computed tomography. We have examined the speed and accuracy of localisation of leucocytes labelled in plasma with a new chelating agent, indium-111 tropolonate, in 90 patients with suspected intra-abdominal abscess. In 50 patients a comparison with ultrasound was made. Nineteen patients had abscesses. The sensitivity and specificity of labelled leucocytes were 95% and 99%, respectively. Comparative results for ultrasound were 60% and 83%. In nine out of 10 patients with abscesses scanned sequentially from 40 min after return of the labelled cells, activity corresponding to the abscess was already visible on the 40 min scan. These results demonstrate that indium-111 plasma labelled leucocyte scanning is both rapid and an accurate method of detecting abscesses.     

99Tcm-nanocolloid imaging in inflammatory bowel disease

We have used 99Tcm-labelled nanocolloid in an attempt to locate areas of inflamed bowel wall or abscesses in five patients with ulcerative colitis and nine with Crohn's disease. The scintigraphic findings were evaluated by comparison with those of recent barium studies and, in three patients, with surgical findings at laparotomy. It proved difficult to localize segments of inflamed bowel accurately with 99Tcm-nanocolloid because of the accumulation of radioactivity in the gut lumen, especially 2 or more hours after injection. However, there was little uptake of the labelled nanocolloid by areas of inflamed gut wall in the period before 2 h. When 99Tcm-nanocolloid scans were compared with 111In-WBC scans in eight patients who had both investigations, 99Tcm-nanocolloid scintigraphy was considerably less sensitive than 111In-WBC scintigraphy. One abscess was located correctly; the other was obscured by nearby bladder and bone marrow radioactivity. We conclude that 99Tcm-nanocolloid scanning is neither sensitive nor reliable enough for assessing the location of inflamed bowel wall or the presence of abscess in patients with inflammatory bowel disease.     

Ultrasound and computed tomography of the abdomen in the staging and management of testicular carcinoma.

Ultrasound and computed tomography (CT) are ideal for imaging enlarged retroperitoneal lymph nodes. The authors evaluated 290 ultrasound and 188 CT examinations in 136 patients with testicular cancer. Although interpretation of CT was more reproducible than that of ultrasound, there was no significant difference in accuracy of enlarged retroperitoneal lymph node detection between the two modalities. Accuracy improved when both examinations were used and interpreted in combination by a single radiologist. Accuracy rates for ultrasound and CT were equal to those reported for lymphangiography. Lymphangiography and excretory urography are no longer routinely indicated in testicular cancer patients.     

The role of computed tomography in the evaluation of Caroli's disease

Two patients with Caroli's disease are reported who did not have renal abnormalities or hepatic fibrosis. Extra hepatic complications of Caroli's disease in these two patients were best evaluated by computed tomography (CT). Although ultrasound evaluates the ductal abnormalities of Caroli's disease well, it does not delineate subphrenic or subhepatic abscesses, pancreatitis, pancreatic phlegmon, or pseudocysts as well CT.     

Percutaneous drainage of abdominal abcess

The mortality in undrained abdominal abscesses is high with a mortality rate ranging between 45 and 100%. The outcome in abdominal abscesses, however, has improved due to advances in image guided percutaneous interventional techniques. The main indications for the catheter drainage include treatment or palliation of sepsis associated with an infected fluid collection, and alleviation of the symptoms that may be caused by fluid collections by virtue of their size, like pancreatic pseudocele or lymphocele. The single liver abscesses may be drained with ultrasound guidance only, whereas the multiple abscesses usually require computed tomography (CT) guidance and placement of multiple catheters. The pancreatic abscesses are generally drained routinely and urgently. Non-infected pancreatic pseudocysts may be simply observed unless they are symptomatic or cause problems such as pain or obstruction of the biliary or the gastrointestinal tract. Percutaneous routes that have been described to drain pelvic abscesses include transrectal or transvaginal approach with sonographic guidance, a transgluteal, paracoccygeal-infragluteal, or perineal approach through the greater sciatic foramen with CT guidance. Both the renal and the perirenal abscesses are amenable to percutaneous drainage. Percutaneous drainage provides an effective and safe alternative to more invasive surgical drainage in most patients with psoas abscesses as well.     

Percutaneous drainage of tuberculous iliopsoas abscesses under image guidance

Most intra-abdominal and other types of fluid collections are now successfully drained percutaneously under image guidance. The utility of percutaneous drainage of tuberculous abscesses, especially those associated with osseous changes, is, however, less well established. Six patients with tuberculous iliopsoas abscesses were successfully managed by percutaneous drainage combined with antituberculous therapy. The abscesses were bilateral in one patient and unilateral in the other five. Drainage was by needle aspiration under ultrasound (US) guidance in one patient, and by catheter under CT guidance in the other patients. Three patients had associated osseous changes. There were no procedural complications. Tuberculous iliopsoas abscess can be successfully treated by percutaneous drainage and appropriate antituberculous therapy.     

Computed tomography in the imaging of colonic diverticulitis

Colonic diverticulitis occurs when diverticula within the colon become infected or inflamed. It is becoming an increasingly common cause for hospital admission, particularly in western society, where it is linked to a low fibre diet. Symptoms of diverticulitis include abdominal pain, diarrhoea and pyrexia, however, symptoms are often non-specific and the clinical diagnosis may be difficult. In addition, elderly patients and those taking corticosteroids may have limited findings on physical examination, even in the presence of severe diverticulitis. A high index of suspicion is required in such patients in order to avoid a significant delay in arriving at the correct diagnosis. Imaging plays an important role in establishing an early and correct diagnosis. In the past, contrast enema studies were the principal imaging test used to make the diagnosis. However, such studies lack sensitivity and have limited success in identifying abscesses that may require drainage. Conversely computed tomography (CT) is both sensitive and specific in making a diagnosis of diverticulitis. In addition, it is the imaging technique of choice in depicting complications such as perforation, abscess formation and fistulae. CT-guided drainage of diverticular abscesses helps to reduce sepsis and to permit a one-stage, rather than two-stage, surgical operation. The purpose of this review article is to discuss the role of CT in the imaging of diverticulitis, describe the CT imaging features and complications of this disease, as well as review the impact and rationale of CT imaging and intervention in the overall management of patients with diverticulitis.     

Transrectal US as an adjunct in the diagnosis of rectal and extrarectal tumors

Transrectal ultrasound (US; also called endosonography) was used to evaluate known or suspected rectal and perirectal masses. Thirty-one patients were examined with commercially available endosonographic probes. Those who obtained and interpreted the sonograms had no knowledge of other diagnostic studies, which included digital rectal and sigmoidoscopic examinations, conventional US, and computed tomography (CT). All but one patient underwent surgical exploration for diagnoses that included rectal cancers, perirectal abscesses, presacral endometriosis, intramural dermoid of the rectum, and intramural venous angioma. Transrectal US was able to image all masses situated within 12 cm of the anus. Malignant infiltration of perirectal fat and perirectal node involvement were detected at least as accurately with US as with CT, suggesting that this technique is a cost-effective, reliable adjunct for staging rectal cancers.     

Multidetector CT appearance of adhesion-induced small bowel obstructions: matted adhesions versus single adhesive bands

Adhesive small bowel obstruction (SBO) is a common cause of abdominal pain after surgery or peritonitis. The role of computed tomography (CT) in the evaluation of SBO has expanded. Diagnosis of adhesive SBO, however, remains challenging. Adhesions causing SBO are classified as either matted adhesions or single adhesive bands, and both types have different mechanisms that lead to SBO. In patients with matted adhesions, SBO results from angulation and kinking or from torsion of the intestines. In patients with adhesive bands, SBO results from compression of the intestine caused by the band itself. Recent advances in spatial resolution using multidetector CT (MDCT) have enabled detailed assessment of the configuration of the SBO site. Presented in this pictorial essay are characteristic MDCT findings regarding the mechanism of the obstruction process of adhesive SBO.     

Computerized tomography in the diagnosis of abscesses of the posterior pararenal space secondary to surgical interventions on the abdomen

The authors analyse the possibilities offered by CT in the diagnosis of the abscesses of the posterior pararenal space (secondary to surgical operation) relating 10 cases observed. The features described by many authors in the latest literature are compared with those observed in the cases reported, showing the real diagnostic sensibility of CT in these situations of relative urgency. The panoramic image offered by CT is particularly useful in the "blind " examinations and in exactly directing the surgical approach or, in alternative, the echo-guided percutaneous puncture of the abscess.     

Inferior vena caval filters: noninvasive evaluation

Transvenous inferior vena caval filters were placed in 32 patients (21 bird's nest [BN] and 11 Kimray-Greenfield [K-G] filters). Positive contrast cavography was performed before and immediately after filter placement as well as during long-term follow-up studies. In 23 patients, computed tomographic (CT) scanning was also performed; in 10 patients, real-time ultrasound (US) study was used as an adjunct. CT scans of the BN filter showed one case of hemorrhage and one case of air embolism, both of which were not recognized at cavography. CT scanning of the K-G filter demonstrated two cases of deep penetration of the prongs and one large retroperitoneal hematoma. Real-time US scanning played a major role in checking the final position of the filter and in determining its stability during repositioning of the upper prongs of one BN filter. Noninvasive examinations, including CT and US scanning, are valuable adjuncts in immediate and long-term follow-up study of patients with inferior vena caval filters.     

Morphologic aspects of hepatic abscesses at computed tomography and ultrasound

The morphologic criteria of hepatic abscesses as demonstrated at computed tomography (CT) and ultrasound (US) were investigated in 27 patients and the diagnostic efficiency of both methods evaluated. Different appearances of hepatic abscess at CT and US were observed and investigated. No specific morphologic signs could be defined, since malignant neoplasms may show similar findings. Therefore, fine needle aspiration of possible hepatic abscesses should be performed to provide specific and bacteriologic diagnosis. US is an accurate method to evaluate patients with possible hepatic abscess. However, CT should be preferred in critically ill patients and postoperatively, since the diagnostic accuracy of CT is not limited by bowel gas, sutures and drainage tubes.     

Appendicoliths,the little giants: A narrative review

ObjectivesThis narrative review aims to collate the data in the existing literature on appendicoliths, by reviewing the available information on appendicoliths that have been previously reported in 24 publications, and providing the information in one article.Key findingsAppendicoliths are frequent culprits in causing luminal obstruction of the appendix, leading to appendicitis. They are calcified masses formed as a result of the aggregation of faecal particulates and inorganic salts within the lumen of the appendix. The presence of appendicoliths in an inflamed appendix influences the patient's treatment, as surgery is usually done to avoid appendix perforation and abscess formation, and also to prevent a future recurrence of the disease. Appendicoliths are mostly imaged using CT, Ultrasound, and plain X-rays; however, CT is the most frequently used modality, particularly in the imaging of complications caused by ‘retained’ appendicoliths. ‘Retained’ appendicoliths and their consequential abscesses have been reported in the sub-hepatic and intrahepatic regions, pelvic and tubo-ovarian regions, gluteal region, subcutaneous layer, subphrenic region, and through the diaphragm into the chest cavity.ConclusionThis review provides useful information on the imaging appearances and complications caused by the presence of appendicoliths in an inflamed appendix, and it also provides information on the clinical implications of ‘dropped’ appendicoliths during appendectomy.Implications for practiceBased on the findings of this review, it is recommended that the appropriate imaging modality (ultrasound and/or CT) should be considered when imaging appendicoliths and its complications. It is also suggested that retained appendicolith be considered a differential diagnosis when imaging patients with a history of appendectomy due to complicated appendicitis/perforation.     

Spinal infection: evaluation with MR imaging and intraoperative US

Magnetic resonance (MR) images of the spine and/or intraoperative spinal ultrasound (US) in 24 patients with spinal infections were reviewed and correlated with clinical and pathologic data to determine their diagnostic value. In disk space infection with osteomyelitis and in retrospinal abscess, MR images showed characteristic findings, whereas in myelitis, MR images demonstrated nonspecific abnormalities. The appearance on MR images of epidural abscesses ranged from clearly identifiable extradural masses with high-intensity signal on spin-echo T2-weighted images to extensive inhomogeneous collections of mixed signal intensities, difficult to distinguish from adjacent meningitis. Myelography with high-resolution computed tomography (CT) and intraoperative spinal US was superior to MR imaging in demonstrating epidural abscesses when there was concomitant meningitis. With intraoperative spinal US, epidural abscesses could be located and their decompression monitored. MR imaging is recommended as the initial screening procedure in spinal infection; in those few patients with nondiagnostic MR images, myelography with high-resolution CT should be the supplementary study. If surgery is planned, intraoperative spinal US should be used.     

Ultrasound of the pancreas: update and controversies

The pancreas is an organ that often presents difficulties for ultrasound exploration due to the interference of abdominal gas in the stomach and duodenum. However, with technical experience and the use of a variety of examination techniques, such as filling the stomach with water or cellulose suspension, changing patient's position, or scanning at different moments of respiration, such as suspended inspiration or expiration, it can be seen in its totality in a high percentage of patients. In our opinion, especially as new technical advances have been incorporated into US equipment (color power Doppler, harmonics, and US pulse inversion) and new contrast agents are available, US can compete with CT in this field. Ultrasound can be as useful as CT in most patients with pancreatitis and pancreatic neoplasms. Furthermore, Endoscopic sonography (ES), as well as intraoperative and laparoscopic techniques, are also excellent for visualizing malignant pancreatic lesions and have a special role in preoperative staging. Finally, US is a good technique to guide fine-needle biopsy of the pancreas and for aspiration of inflammatory fluid collections and abscesses. Although CT has played a major role to date, US is presently the most widely available and economical means to visualize the pancreas.     

Septic thrombosis of the portal vein: CT and clinical observations

The CT and clinical findings were reviewed in seven patients with septic thrombosis of the portal vein (STPV). Of the seven patients, five had associated pyogenic liver abscesses. Five of seven patients presented de novo with STPV without a clinically obvious extrahepatic source of intraabdominal infection. All seven patients were successfully managed nonsurgically with intravenous antibiotics and in two patients percutaneous drainage of hepatic abscesses. Serial follow-up examinations in five patients demonstrated complete resolution of portal venous thrombus in three patients and progression to cavernous transformation in two. When diagnosed early by CT or sonography, STVP may have a more benign clinical course following appropriate antibiotic therapy.     

CTPA for the diagnosis of acute pulmonary embolism during pregnancy

CT pulmonary angiography (CTPA) has been suggested by the Fleischner society as the first test following a negative leg ultrasound in pregnant patients with suspected pulmonary embolism. This editorial discusses the use of CTPA as a diagnostic tool in pregnant women and comments on the need for specifically adapting CT protocols during pregnancy in the light of new research describing a substantial number of non-diagnostic examinations in pregnant women if routine scanning protocols are used for CTA of the pulmonary arteries. Potential reasons for these high numbers of insufficient examinations are physiological changes occurring during pregnancy that lead to a hyperdynamic circulation, which reduces average enhancement of the pulmonary vasculature. In addition, there are possible breathing-related effects that include an increased risk for Valsalva manoeuvre with devastating effects for pulmonary vascular enhancement. Techniques to overcome these problems are discussed: bolus triggering with short start delays, high flow rates or high contrast medium concentration, preferential use of fast CT systems and the use of low kVp CT techniques. CT data acquisition during deep inspiration should be avoided and shallow respiration may be considered as an alternative to suspended breathing in this patient group. All these factors can contribute to optimization of the quality of pulmonary CTA in pregnant patients. It is time now to adapt our protocols and provide optimum care for this sensitive patient group.     

Computed tomography-guided percutaneous drainage of splenic abscesses

OBJECTIVE: The aim of the study is to evaluate the role of computed tomography (CT)-guided percutaneous drainage in the management of solitary splenic abscesses. MATERIALS AND METHODS: Sonography and CT were used in the initial diagnosis of splenic abscess in patients with vague left upper quadrant pain and/or fever. Solitary splenic abscesses of nine male patients whose ages varied between 21 and 27 years (mean age: 24.7 years) were percutaneously drained under CT guidance. Puncture with 18-gauge Chiba needles and coaxial guidewire technique was used for insertion of six or eight French pigtail catheters. Antibiotics in accordance with the microbiological results were also given adjuvant to drainage. Follow-up examinations were performed by sonography, daily for the first week and weekly for the next 7 weeks, and by CT at the end of first, fourth and eighth weeks. RESULTS: All patients tolerated the intervention well, except for one complicating with splenic rupture and hemorrhage, who underwent emergency splenectomy. The remaining eight patients recovered within 4 weeks without any splenic sequela. A mean of 3.9 days was needed before removing the drainage catheter based on regression criteria. DISCUSSION AND CONCLUSION: CT-guided percutaneous drainage of splenic abscesses may be proven effective and is superior to splenectomy in selected cases, as it preserves host immunity.