Diastasis of rectus abdominis muscles: patterns of anatomical variation as demonstrated by ultrasound.

PURPOSE: The aim of our study was to categorise the anatomical variations of rectus abdominis muscle diastasis (diastasis recti) by using ultrasound (US). MATERIAL AND METHODS: In a one-year period 92 women were evaluated with US because of suspected diastasis of rectus muscles. Patients were examined in a supine position, with head extended, upper limbs aligned to the trunk, and knees flexed. US was performed with high-frequency, broad-band transducers. Trapezoid field-of-view and extended field-of-view were employed to measure diastasis exceeding 5 cm. Diastasis was defined as a margin-to-margin distance > 20 mm at rest and classified according to the following anatomical patterns: open only above the navel, open only below the navel, open at the navel level, open completely but wider above the navel, and open completely but wider below the navel. RESULTS: Diastasis was found in 82 patients (30-61 years old, mean age 35 years). The width was 21-97 mm, mean 39 mm. The prevalence and severity of the anatomical patterns was as follows: open only above the navel in 48 patients (21-88 mm, mean 40 mm), open only below the navel in one patient (33 mm), open at the navel level in seven patients (23-39 mm, mean 34 mm), open completely but wider above the navel in 24 patients (21-97 mm, mean 41 mm), open completely but wider below the navel in two patients (21-29 mm, mean 25 mm). CONCLUSIONS: The above-navel patterns of recti muscle diastasis are the most common. Even when open completely, diastasis is usually wider above the navel. Knowledge of the anatomical type of rectus muscle diastasis could be of value to the patient (exercises to do and to avoid) and to the surgeon (abdominoplasty planning).

Integrating contrast-enhanced sonography in the follow-up algorithm of hepatocellular carcinoma treated with radiofrequency ablation: single cancer center experience.

BACKGROUND: Hepatocellular carcinoma (HCC) patients treated with percutaneous ablation require close follow-up for early detecting and treating tumor recurrence. PURPOSE: To illustrate our single-center prospective experience on using contrast-enhanced ultrasound (CEUS) as a follow-up tool alternated with computed tomography (CT). MATERIAL AND METHODS: In a 7-year period 588 patients with one to three HCCs were treated with radiofrequency ablation (alone or combined with ethanol injection). Patients with completely ablated tumors at 1-month CT scan were followed up serially, using alternated CEUS (one microbubbles injection per lobe) and CT every 3 months for 2 years. In few cases magnetic resonance imaging (MRI) was employed instead of or in addition to CT. The following patterns of recurrence were considered: A, enhancing tissue within the lesion; B, enhancing tissue adherent to the lesion; C, enhancing tissue within the same liver segment of the treated nodule; and D, enhancing tissue within a different segment. Patients with positive CEUS underwent confirmatory CT/MRI (standard reference). RESULTS: Median follow-up was 19 months. There were 221 recurrences. Three pattern A recurrences (2 detected by CEUS and 1 by CT), 86 pattern B recurrences (44 detected by CEUS and 42 by CT), 70 pattern C recurrences (32 detected by CEUS and 38 by CT), and 62 pattern D recurrences (23 detected by CEUS and 39 by CT). CT detected additional nodules in 16/101 patients with positive CEUS. CONCLUSION: CEUS follow-up of HCC patients after ablation is feasible. Since 72% recurrences develop in the same segment of the necrotic nodule, CEUS proves to be effective despite the minor visualization of the entire liver during the arterial phase when compared to CT and MRI. Including CEUS in patient follow-up may reduce the number of CT and MRI examinations.

Bedside contrast-enhanced sonography of critically ill patients.

The transfer of critically ill patients to the radiology department is, in itself, potentially dangerous, so radiologists are frequently asked to perform bedside sonographic studies in the intensive care unit, surgical or medical department, sterile area, and operating room. In these circumstances, injection of a contrast agent may give the radiologist relevant additional information, which is useful for diagnosis and for better therapeutic management of these critically ill patients. Contrast-enhanced sonography may allow detection of findings not recognizable on baseline sonography or even color Doppler imaging. In this pictorial essay, we highlight the value of real-time contrast-enhanced sonography when performed at the bedside in critically ill patients.

Thrombosis and cancer: spectrum of multidetector CT findings in oncologic patients with thromboembolic disease. A pictorial review.

This article is a reasoned pictorial review illustrating the many faces of thrombotic and embolic disease developing in the cancer patient. From a clinical point of view, we particularly point out the importance of properly identifying this occurrence in its various presentations. From a radiological point of view, special emphasis is given to the wide spectrum of multidetector CT findings, to the clues of benign and malignant thrombus diagnosis, and to the potential interpretative pitfalls.

Transient hepatic echogenicity difference on contrast-enhanced ultrasonography: sonographic sign and pitfall.

OBJECTIVE: The purpose of this study was to report and analyze a new contrast-enhanced ultrasonographic (CEUS) imaging finding, the transient hepatic echogenicity difference due to perfusion changes, using computed tomography (CT) as a reference standard. METHODS: We retrospectively investigated the records of patients evaluated in a 2-year period, selecting those who had undergone both CT and CEUS within 15 days, who had CT evidence of a perfusion abnormality, and who had had a CEUS study that included the malperfused parenchymal area. RESULTS: There were 30 patients with 44 hepatic perfusion changes on CT scans (28 around liver focal lesions and 16 unrelated to focal lesions). Retrospectively, CEUS allowed recognition of 21 of 28 perifocal transient hepatic attenuation differences (THADs), 6 of 10 subsegmental THADs, 2 of 3 segmental THADs, and 1 of 3 lobar THADs. Only some of these abnormalities had been identified at the original CEUS examinations: 0 of 3 lobar THADs, 1 of 3 segmental THADs, 2 of 10 subsegmental THADs, and 16 of 28 perifocal THADs. CONCLUSIONS: Contrast-enhanced ultrasonography can show hepatic perfusion abnormalities similar to those well known from CT literature, although with a lower sensitivity. Knowledge of this transient hepatic echogenicity difference phenomenon may be relevant for avoiding incorrect image interpretation or incorrect tumor size measurement and for eventually identifying occult vascular disorders such as venous thrombosis or fistulas.

Real-time harmonic contrast material-specific US of focal liver lesions.

Recent advances in contrast material-enhanced ultrasonography (US) mainly include (a) development of low-acoustic-pressure (low-mechanical-index) harmonic software, capable of obtaining real-time images without disrupting contrast material microbubbles, and (b) commercialization of new contrast media ("second-generation" contrast media), capable of producing intense echo signals in this low-mechanical-index setting. With use of low-mechanical-index continuous-mode contrast-enhanced US, the circulatory kinetic models of various focal liver lesions can be displayed dynamically. Hepatic lesions usually have typical perfusion characteristics and enhancement patterns through the various phases of parenchymal enhancement, which helps characterize lesions and, in most cases, allows definitive diagnosis, even among lesions that exhibit very similar baseline appearances. Because of the use of harmonic technologies at low emission frequencies, there is some loss of spatial resolution and overall image quality, typically resulting in a grainy appearance. In addition, lesion depth affects the detectability of vascularity to some degree in that poor signal arises from deep-seated lesions. Moreover, liver attenuation (eg, in patients with steatosis or chronic liver disease) further reduces the sensitivity of contrast-enhanced US. Nevertheless, with its unique capacity to provide images in real time, low-mechanical-index contrast-enhanced US is the dynamic imaging modality of choice in the differential diagnosis of focal liver lesions.

Gastrointestinal stromal tumours: Pictorial review.

Gastrointestinal stromal tumours (GIST) are the most common mesenchymal tumours of the alimentary tract. They normally involve the stomach, the small bowel, or the colon. Localisation within the oesophagus, rectum, mesentery, omentum, or retroperitoneum is less common. GISTs are immunohistochemically identified by the expression of the c-kit protein, which is not detected in other mesenchymal tumours. The role of imaging includes the detection (subjects with occult gastrointestinal bleeding, incidental recognition, etc.), characterisation, analysis of relations between mass and gastrointestinal wall, staging, prognostic assessment (recognition of signs of malignancy and unfavourable prognosis), and follow-up during specific treatment. Owing to the frequent exophytic growth of these lesions, differentiation of these tumours from nondigestive lesions of different nature is a common diagnostic problem. Imaging findings usually allow differentiation from gastrointestinal epithelial tumours but not from non-epithelial tumours, for which histological confirmation is necessary, in part to verify potential response to therapy. Smaller lesions, which are usually benign, tend to be well-defined, relatively homogeneous, and with intraluminal growth. Larger lesions normally show well-defined or ill-defined margins, inhomogeneous density both on unenhanced and on contrast-enhanced scans, with combined intraluminal/extraluminal growth and a tendency to spread to surrounding structures. Internal attenuation is often necrotic or clearly fluid. Signs of high-grade GIST include liver metastasis, gastrointestinal wall infiltration, large volume, irregular surface, ill-defined margins, inhomogeneous enhancement and peritoneal spread. Recurrences usually share the appearance of the larger, primary malignant GIST.

Real-time, contrast-specific sonography imaging of acute splenic disorders: a pictorial review.

Real-time, contrast-specific ultrasonography (US) uses low-mechanical-index, harmonic software to stimulate echo emission from resounding second-generation contrast medium microbubbles. At our institution, contrast-enhanced US is increasingly being used in the evaluation of acute abnormalities of the spleen, mainly to overcome some limitations of conventional (basic) US. This pictorial essay illustrates the appearance of several acute splenic lesions, both traumatic and nontraumatic, on contrast-specific US.

Suspected ureteral colic: primary helical CT versus selective helical CT after unenhanced radiography and sonography.

OBJECTIVE: The purpose of this study was to compare the accuracy of unenhanced helical CT with combined sonography and unenhanced radiography in patients with acute flank pain suggestive of ureteral colic. SUBJECTS AND METHODS: From January 1997 to December 1999, 181 consecutive patients with acute flank pain underwent unenhanced radiography, sonography, and unenhanced helical CT (protocol A). From January 2000 to December 2000, 96 consecutive patients arriving at the emergency department with acute flank pain were alternately submitted either to primary unenhanced helical CT (protocol B, 48 patients) or to unenhanced radiography and sonography with the addition of helical CT in unclear cases (protocol C, 48 patients). RESULTS: When compared with the diagnostic accuracy for ureterolithiasis of the combined sonography and radiography in the same group of subjects (protocol A), CT had a greater sensitivity (92% vs 77%), negative predictive value (87% vs 68%), and overall accuracy (94% vs 83%). Among patients who underwent primary CT (protocol B), we found three false-negatives (all with spontaneous stone passage) and no false-positives. Among patients initially examined with unenhanced radiography and sonography (protocol C), we found one false-positive (leading to patient admission and needless repeated radiographic and sonographic studies) and six false-negatives (all followed by an uncomplicated course and spontaneous passage); CT depicted four of these stones but did not result in change in treatment. Fourteen percent of the patients in protocol C required invasive treatment, but combined sonography and radiography showed stones and hydronephrosis in all these patients. CONCLUSION: Unenhanced CT was the most accurate modality for determining the presence of ureterolithiasis. The combination of abdominal radiography and sonography, however, yielded comparable results with no clinically important misdiagnoses and thus can be used as an alternative when CT resources are limited.

Acute flank pain: comparison of unenhanced helical CT and ultrasonography in detecting causes other than ureterolithiasis.

Several conditions can clinically mimic renal colic. We assessed the accuracy of non-contrast-enhanced helical CT and of ultrasonography (US) in offering an alternative explanation for flank pain. In a 3-year period, 181 patients with acute flank pain underwent US and non-contrast-enhanced helical CT in a blinded sequence. Their efficacy in detecting both alternative causes of pain and additional findings unrelated to the pain was assessed in 160 cases with a confirmed diagnosis. An alternative cause was found in 23 cases (14%). US gave 4 false-negative results (1 acute appendicitis, 1 ovarian cyst torsion, 1 diverticulitis, and 1 papillary necrosis) and 2 false-positive results (1 acute pyelonephritis and 1 diverticulitis), with a 78% sensitivity and a 98% specificity for nonlithiasic causes. CT gave 5 false-negative results (1 complicated ovarian cyst, 1 pleuritis, 1 epididymitis, 1 acute pyelonephritis, and 1 papillary necrosis) and 1 false-positive (1 simple ovarian cyst described as a complicated lesion), resulting in a 74% sensitivity and a 99% specificity for diagnosing alternative causes. There were 130 additional US findings in 68 patients and 151 additional CT findings in 77 patients. A wide spectrum of findings can be identified in subjects imaged for flank pain. Non-contrast-enhanced helical CT and US have comparable accuracy in diagnosing causes other than stone disease.