HIP OBLIQUE AXIAL MRI PLANNING
HIP OBLIQUE AXIAL MRI PLANNING AND REFERENCE LINES
Posts
Choice of MRI or CT in orbital lesions
Proptosis: For most of the non-vascular lesions, pseudotumor, orbital cellulitis, thyroid eye diseases orbital cysticercosis, MRI is modality of choice. However, certain facts must be kept in mind if we suspect calcification in lesion, bony erosion or hyperostosis then CT is a better option, but MRI will be a better option if we suspect extension of lesion in orbital apex, optic canal or intracranial extension. For vascular lesions such as arterio- venous malformations, orbital varix and carotico- cavernous fistulas, MRI and MRI with contrast are better options. Retinoblastoma: MRI is the better choice. However, it will not pick up calcification. Papilledema and optic neuritis: MRI is the better option. Isolated 3 rd nerve plasy: MRI with MRA to detect posterior communicating artery aneurysm, but sometimes MRA can miss aneurysm less than 5 mm in size. Multiple cranial nerve palsy: MRI is better choice. Sometimes T2* weighted images are required to study the intracranial cours...
Luminal contrast and distension CT enterography
Neutral or low-density oral contrast media are a prerequisite for good-quality CT enterography [3-5] because they maximise contrast between the lumen and enhancing small bowel wall, facilitating assessment of mucosal thickening and wall stratification/enhancement patterns [1-8]. Water–methylcellulose solution, polyethylene glycol, commercially available low-density barium, 0.1% Volumen (Bracco, Milan, Italy) and milk are examples of neutral oral contrast agents with CT attenuation properties similar to that of water. Water alone usually results in inadequate distension due to rapid reabsorption, although some authors advocate its use [9]. Use of Volumen has been shown to improve the quality of bowel distension compared with water alone [4,10-12], but it remains unlicensed for use in the UK and therefore is not available. Milk was shown to give similar results as Volumen [13], but although less expensive and freely available in Europe, it may be deemed unpalatable by many patients wh...