Assessment of diffusion-weighted imaging for characterizing focal liver lesions.

In 150 patients, 153 hepatic lesions (39 metastases, 27 hemangiomas, 26 hepatocellular carcinomas, 25 cysts, 15 adenomas, 8 focal nodular hyperplasias, 5 abscesses, 4 hamartomas, and 4 cholangiocarcinomas) were evaluated during a 24-month period. Apparent diffusion coefficient (ADC) values of benign lesions (1.994×10(-3) mm(2) s(-1)) were significantly higher than ADC values of malignant lesions (1.070×10(-3) mm(2) s(-1)). Mean ADC value for solid benign lesions (1.143×10(-3) mm(2) s(-1)±0.214×10(-3) mm(2) s(-1)) was not significantly different from malignant lesions. ADC values did not allow differentiating malignant from benign solid lesions (area under the curve=0.61). ADC cutoff value threshold of 1.6×10(-3) mm(2) s(-1) yielded higher accuracy for differentiating benign from malignant lesions.

Imaging of degenerative lumbar intervertebral discs; linking anatomy, pathology and imaging.

Low back pain is a common medical condition that has significant implications for healthcare providers and the UK economy. Low back pain can be classified as 'specific' in which an underlying pathophysiological mechanism is identified (eg, herniated intervertebral disc). Advanced imaging should be performed in this situation and in those patients in whom systemic disease is strongly suspected. In the majority (approximately 90%), low back pain in 'non specific' and there is a weak correlation with imaging abnormalities. This is an area of ongoing research and remains controversial in terms of imaging approach and treatment (eg, theory of discogenic pain, interpretation and treatment of endplate changes). With regards Modic endplate changes, current research suggests that an infective component may be involved that may identify novel potential treatments in patients with chronic low back pain refractory to other treatment modalities. MRI is the imaging modality of choice for the assessment of degenerative changes in intervertebral discs. MRI has superior soft tissue contrast resolution when compared to other imaging modalities (eg, plain radiography, CT). An understanding of normal anatomy and MR appearances of intervertebral discs, particularly with regards to how these appearances change with advancing age, is required to aid image interpretation. Knowledge of the spectrum of degenerative processes that may occur in the intervertebral discs is required in order to identify and explain abnormal MRI appearances. As the communication of MRI findings may guide therapeutic decision making and surgical intervention, the terminology used by radiologists must be accurate and consistent. Therefore, description of degenerative disc changes in the current paper is based on the most up-to-date recommendations, the aim being to aid reporting by radiologists and interpretation of reports by referring clinicians.

Radiological appearances of gynaecological emergencies.

BACKGROUND: The role of various gynaecological imaging modalities is vital in aiding clinicians to diagnose acute gynaecological disease, and can help to direct medical and surgical treatment where appropriate. It is important to interpret the imaging findings in the context of the clinical signs and patient's pregnancy status. METHODS: Ultrasound and Doppler are readily available in the emergency department, and demonstrate features of haemorrhagic follicular cysts, ovarian cyst rupture, endometriotic cysts and pyosalpinx. Adnexal torsion may also be identified using ultrasound and Doppler, although the diagnosis cannot be safely excluded based on imaging alone. Computed tomography (CT) is not routinely employed in diagnosing acute gynaecological complications. However due to similar symptoms and signs with gastrointestinal and urinary tract pathologies, it is frequently used as the initial imaging modality and recognition of features of gynaecological complications on CT is important. RESULTS: Although MRI is not frequently used in the emergency setting, it is an important modality in characterising features that are unclear on ultrasound and CT. CONCLUSION: MRI is particularly helpful in identifying the site of origin of large pelvic masses, such as haemorrhagic uterine fibroid degeneration and fibroid prolapse or torsion. In this article, we review the imaging appearances of gynaecological emergencies in non-pregnant patients. TEACHING POINTS: • Ultrasonography is easily accessible and can identify life-threatening gynaecological complications. • Tomography scanners and computed radiography are not routinely used but are important to recognise key features. • MRI is used for the characterisation of acute gynaecological complications. • Recognition of the overlap in symptoms between gastrointestinal and gynaecological conditions is essential.

Eicosapentaenoic acid confers neuroprotection in the amyloid-beta challenged aged hippocampus.

Among the changes that occur in the hippocampus with age, is a deficit in long-term potentiation (LTP). This impairment is associated with inflammatory changes, which are typified by increased concentration of the pro-inflammatory cytokine interleukin-1beta (IL-1beta). Activated microglia are the most likely cell source of IL-1beta, but data demonstrating an age-related increase in microglial activation is equivocal. Here we demonstrate that the age-related deficit in LTP is accompanied by increased expression of cell surface markers of activated microglia (major histocompatibility complex II and CD40) and increased IL-1beta production, and that these changes may be stimulated by interferon-gamma. Treatment of aged rats with eicosapentaenoic acid (EPA) attenuates these changes and we suggest that IL-4 mediates the action of EPA. We demonstrate that aged rats exhibit an exaggerated response to intracerebroventricular injection of beta-amyloid peptide 1-40 (Abeta). Thus Abeta inhibited LTP in aged, but not young, rats and induced a further increase in hippocampal IL-1beta concentration. Of particular significance is the demonstration that EPA protects the aged brain so that the increased vulnerability to Abeta is ameliorated in EPA-treated rats.