Multidetector Computed Tomography (MDCT) Findings of Complications of Acute Cholecystitis. A Pictorial Essay.

Acute cholecystitis stands out as one of the most common surgical pathologies that should always be considered in a right-upper abdominal pain emergency. For this, the importance of a correct diagnosis is well described. However, it has been demonstrated that the simple combination of clinical (pain, Murphy's sign) and laboratory (leukocytosis) parameters alone does not provide for ruling in or ruling out the diagnosis of this condition, unless accompanied by a radiological exam. For a long time, and still today, ultrasonography (US) is by far the first-to-proceed radiologic exam to perform, thanks to its rapidity and very high sensibility and specificity for the diagnosis of simple acute cholecystitis. However, acute cholecystitis can undergo some complications that US struggles to find. In addition to that, studies suggest that multidetector computed tomography (MDCT) is superior in showing complicated forms of cholecystitis in relation to sensibility and specificity and for its capability of reformatting multiplanar (MPR) reconstructions that give a more detailed view of complications. They have shown to be useful for a precise evaluation of vascular complications, the anatomy of the biliary tree, and the extension of inflammation to surrounding structures (i.e., colitis). Therefore, based also on our experience, in patients with atypical presentation, or in cases with high suspicion for a complicated form, a MDCT abdomen scan is performed. In this review, the principal findings are listed and described to create a CT classification of acute complications based on anatomical and topographic criteria.

Ultrasound diagnosis of typhlitis.

PURPOSE: Typhlitis, also known as neutropenic colitis, is a rare inflammatory condition and a potentially life-threatening disease process that typically involves the cecum. Delay in diagnosis may lead to a fatal prognosis with a death rate of 21-48%. Ultrasound evaluation of right lower quadrant may lead to an accurate and rapid diagnosis. METHODS: We describe the case of a 59-year-old female with advanced Churg-Strauss syndrome treated with cyclophosphamide, with acute right lower quadrant pain. RESULTS: Ultrasound was the first diagnostic step in the diagnosis of typhlitis. Sonographic findings were comparable to CT imaging. CONCLUSIONS: Bowel bedside ultrasound evaluation in emergency settings may lead to a prompt and definitive diagnosis. Although CT is considered the gold standard in the diagnosis and staging of neutropenic colitis, ultrasound was able to identify the pathology accurately. Ultrasound findings of typhlitis are highly characteristic, showing circumferential wall thickening with predominant submucosa.

Intraluminal gel ultrasound and eco-color doppler: new tools for the study of colorectal cancer in mice.

AIM: Azoxymethane (AOM) is a potent carcinogen that induces colorectal cancer in mice. Intraluminal gel ultrasound is a technique based on the injection of gel into the rectum. This technique allows the colon to be straightened and to visualize and identify tumours. MATERIALS AND METHODS: Twenty female C57Bl/6J mice were injected intraperitoneally with 10 mg/kg of AOM one time per week for six weeks. The mice were monitored by ultrasound with a Vevo 2100 system. We evaluated the tumour area and tumour vasculature with Ecocolor-Doppler (ECD). Histological examination of sacrificed mice was employed as the standard protocol. RESULTS: After 40 weeks from the injection, ultrasound analysis revealed the presence of tumours in 50% of all mice. Ex vivo analysis revealed the presence of 57% true-positives and only one false-positive. In two mice, ultrasound did not reveale the presence of tumour due to its small dimension. This indicates that ultrasound is able to detect only tumours with sizes ≥3 mm². CONCLUSION: Ultrasound is a rapid examination compared to other diagnostic techniques. It has a good sensitivity when the tumours reach the dimensions of 3 mm² or more. Intraluminal gel allows for the tumour area to be evaluated when mice are still alive, while ECD allows for vasculature of intestinal walls and colorectal tumour to be evaluated.

Non-small cell lung cancer evaluated with quantitative contrast-enhanced CT and PET-CT: net enhancement and standardized uptake values are related to tumour size and histology.

BACKGROUND: Personalized cancer therapy remains a challenge. In this context, we attempted to identify correlations between tumour angiogenesis, tumour metabolism and tumour cell type. To this aim, we used single=phase multidetector computed tomography (MDCT) and hybrid positron emission tomography-computed tomography (PET/CT) to determine whether net enhancement and standardized uptake value (SUVmax) were correlated with tumour size and cytology in patients affected by non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: Our study included 38 patients (30 men, 8 women, mean age 70) with a NSCLC measuring between 3 cm and 7 cm, using a 16-slice multidetector CT (Brilliance Philips) and with PET-CT (Biograph 16 Siemens Medical Solutions). The following lesion parameters were evaluated: maximum diameter, medium density before contrast injection (CTpre), medium density after contrast injection (CTpost average), density in the most enhanced part of the lesion after contrast (CTpost max), net enhancement, SUVmax, age, and cytology. Correlation coefficient and p-value were computed for each pair of variables. In addition, correlations were computed for each pair of variables, and for all combinations of tumour types. We focused on subsets of data with more than 10 observations, and with correlation r>0.500 and p<0.05. RESULTS: A weak correlation (r=0.32; p=0.048) was found between SUVmax and tumour size; the correlation was stronger for masses larger than 31 mm (r=0.4515; p=0.0268). No other correlations were found among the variables examined. CONCLUSIONS: Our data may have prognostic significance, and could lead to more appropriate surgical treatment and better treatment outcome.

Role of imaging in the assessment of impacted foreign bodies in the hypopharynx and cervical esophagus.

Impaction of foreign bodies in the upper digestive tract is a serious pathologic condition in ear, nose, and throat practice and is particularly common in children, prisoners, and psychiatric patients. Commonly found objects include fish bones, chicken bones, pieces of glass, dental prostheses, coins, and needles. The goals of the initial patient assessment are to identify the type of object, its location in the gastrointestinal tract, the presence of any associated complications, and the presence of any underlying esophageal conditions. Radiographic evaluation is helpful to confirm the location of foreign bodies and associated complications. Plain films of the neck and chest commonly will show the location of radiopaque objects, such as coins. Both anteroposterior and lateral views are necessary, as some radiopaque objects overlying the vertebral column may only be visible on the lateral view. Multidetector row computed tomography is superior to plain radiographs for the detection of pharyngoesophageal foreign bodies and provide additional crucial information for the management of complicated cases especially related to sharp or pointed ingested foreign bodies.

Communication of findings of radiologic examinations: medicolegal considerations.

Radiologists receive little formal training regarding the structure of the radiology report and its importance as a medicolegal document; failure to communicate, in fact, represents one of the main problems facing the modern radiologists' activity. Duty to the patient does not end anymore with the written report; the paradox is that we are so advanced in imaging technology, but not in communicating imaging findings. Communication must be timely, appropriate, and fully documented. There is an increasing trend to communicate results directly to the patients; radiologists have the greatest problem when communicating unexpected findings. To improve patient care and reduce the risk of being sued, radiologists should follow shared report guidelines and be more familiar with their professional responsibilities.

Preliminary study on the correlation between grading and histology of solitary pulmonary nodules and contrast enhancement and [18F]fluorodeoxyglucose standardised uptake value after evaluation by dynamic multiphase CT and PET/CT.

AIM: To evaluate whether the histology and grading of solitary pulmonary nodules (SPNs) correlated with the results of dynamic multiphase multidetector CT (MDCT) and the [(18)F]fluorodeoxyglucose standardised uptake value (SUV) in 30 patients. METHODS: Chest x-rays of 270 patients with incidentally detected SPNs were retrospectively evaluated. Thirty patients with histologically proven SPNs were enrolled. On MDCT and positron emission tomography (PET)/CT images, two experts measured the density of nodules in all perfusion phases and the SUV. Net enhancement (NE) was calculated by subtracting peak pre-contrast density from peak post-contrast density. The Pearson test was used to correlate nodule NE, SUV, grading, histology and diameter. RESULTS: Of the 30 malignant SPNs, six were classified as G1 (median NE, 31.5 Hounsfield units (HU); median SUV, 4.8 units), 15 were classified as G2 (median NE, 49 HU; median SUV, 6 units), and nine were classified as G3 (median NE, 32 HU; median SUV, 4.5 units). A highly negative correlation was found in G3 SPNs between NE and the corresponding diameters (r=-0.834; p=0.00524). NE increased with the increase in diameter (r=0.982; p=0.284). SUV increased as the SPN diameter increased (r=0.789; p=0.421). NE and SUV were higher in G2 than G1 SPNs, and lower in G2 than G3 SPNs (r=0.97; p=0.137). CONCLUSIONS: The significant correlation in dedifferentiated (G3) SPNs between NE and diameter (r=-0.834; p=0.00524) supports the theory that stroma and neoangiogenesis are fundamental in SPN growth. The highly negative correlation between NE and diameter demonstrates a net decrease in perfusion despite an increase in dimension. The multidisciplinary approach used herein may result in a more precise prognosis and consequently a better therapeutic outcome, particularly in patients with undifferentiated lung cancer.