Multimodality imaging of the gastrointestinal manifestations of scleroderma

Scleroderma is a complex multisystem connective tissue disorder. Early visceral disease, such as gastrointestinal (GI) involvement, is associated with significant morbidity and a poorer prognosis. Prompt diagnosis is crucial to allow disease modifying therapies be initiated early in the course of the disease. The primary underlying pathophysiology in the GI tract is dysmotility, muscular atrophy, and fibrosis, and this is reflected in the imaging features. In this paper, we demonstrate the imaging appearances of involvement of the GI tract and describe the use of advanced imaging with magnetic resonance enterography (MRE). A multimodal imaging approach is required to identify both characteristic features of scleroderma and potential complications. Traditional fluoroscopic contrast (barium) studies are still commonly performed for assessment of the oesophagus. More recent advances in cross-sectional imaging allow for thorough three-dimensional assessment of the entire GI tract. MRE is particularly useful for small bowel evaluation while also allowing "pseudodynamic" functional imaging and concomitant assessment of the other abdominal viscera and structures.

Utility of positron emission tomography/CT in the evaluation of small bowel pathology

We describe the management principles and different roles of positron emission tomography (PET)/CT in the evaluation of patients with small bowel tumours (adenocarcinoma, gastrointestinal stromal tumour, lymphoma, metastases) from initial staging, monitoring response to treatment, to detection of recurrent disease. We also discuss the various non-malignant aetiologies of small bowel fludeoxyglucose (FDG) PET uptake, and other pitfalls in FDG PET/CT interpretation. Awareness of the imaging appearances of small bowel tumours, patterns of disease spread and potential PET/CT interpretation pitfalls are of paramount importance to optimise diagnostic accuracy.

Radiological evaluation of adrenal incidentalomas: current methods and future prospects

Incidental adrenal lesions are very common. Computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) all have a role to play in characterizing adrenal lesions. The purpose of this review is to discuss the rationale behind both established and emerging imaging techniques. We also discuss how to follow up incidentally found lesions.

MR enterography in the evaluation of small bowel dilation

Magnetic reasonance (MR) enterography enables high contrast resolution depiction of the location and cause of bowel obstruction through a combination of predictable luminal distension and multiplanar imaging capabilities. Furthermore, because the patient is not exposed to ionizing radiation, sequential "dynamic" MR imaging can be performed repeatedly over time further facilitating depiction of the site and/or the cause of obstruction. With increasing availability of MR imaging and standardization of the oral contrast medium regimens, it is likely that this technique will assume an ever-increasing role in the evaluation of small bowel dilation in the coming years. We illustrate the utility of MR enterography in the evaluation of small bowel dilation, whether it be mechanical, functional (e.g., ileus), or related to infiltrative mural disease.

CT evaluation of Chamberlain's, McGregor's, and McRae's skull-base lines

AIM

To evaluate the mean distance from the odontoid process of C2 to the standard skull-base lines (Chamberlain's, McGregor's, and McRae's lines) on computed tomography (CT) imaging. To compare these measurements to previously documented plain radiograph and magnetic resonance imaging (MRI) measurements.

MATERIALS AND METHODS

Reformatted midline sagittal CT images of 150 adults were retrospectively evaluated. The shortest perpendicular distance was measured from the Chamberlain's, McGregor's and McRae's baselines for each subject to the odontoid tip. Statistical analysis was performed to compare the CT data with the previously obtained MRI and plain film data.

RESULTS

The mean position of the odontoid process was 1.4mm below Chamberlain's line (median 1.2 mm, SD 2.4 mm), 0.8 mm (median 0.9 mm, SD 3 mm) below McGregor's line and 5 mm (median 5 mm, SD 1.8 mm) below McRae's line. There is no significant difference between male and female results (p>0.05) or between these CT and previous MRI measurements (p>0.05).

CONCLUSION

These results provide the mean and range of normal distance from the odontoid process to the most frequently used skull-base lines on the current population on CT.

MRI evaluation and measurement of the normal odontoid peg position

AIM

To measure the normal distances (and range) from the tip of the odontoid peg to the different reference skull baselines (Chamberlain's, McGregor's, and McRae's line) using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We retrospectively evaluated midline sagittal MRI brain images of 200 adults chosen randomly. Patients did not have symptoms or signs suggestive of basilar impression, spinal trauma, vertebral collapse or disease. Using SPSS data analysis program histograms, mean and standard deviation (SD), median and range values were calculated. These findings were then compared with previous plain radiograph measurements.

RESULTS

The mean position of the odontoid peg was 1.2 mm (median 1.5 mm, SD 3 mm) below Chamberlain's line; 0.9 mm (median 1.1, SD 3 mm) below McGregor's line; and 4.6 mm (median 4.8, SD 2.6) below McRae's line.

CONCLUSION

Based on the current population, these results provide the mean and range of normal distances from the odontoid peg to the most frequently used skull baselines using MRI.