Chemical-shift micro-imaging of subcutaneous lesions

Abstract

A chemical-shift imaging technique was used for the study of small subcutaneous lesions. This study concerns micro-imaging of two females suffering from a tenosynovial giant cell tumor and an epidermal cyst. High-resolution water, fat and chemical-shift artifact-free images were obtained on a whole-body MR unit (1.5 T) equipped with a 23-mm microscopy surface coil and standard gradients (23 mT/m). A significant improvement in signal-to-noise ratio was achieved by reducing the receiver bandwidth to values below +/-10 kHz. The image data sets were acquired with resolution 0.1 x 0.13 mm in the plane, slice thickness 0.5 mm and with acquisition time less than 3 min. Spatial resolution, fat suppression, image texture and edge delineation were improved on spectroscopic images compared with those on conventional MR images.

Clinical and Experimental Pancreatic Islet Transplantation to Striated Muscle

“…The MRI technique used yields a very high in-plane resolution of 200 μm in vivo (33), which is required to accurately visualize the islet grafts. Islets could indeed be detected in muscle tissue at the site of injection in all three patients (Fig.…”

Microimaging of hairless rat skin by magnetic resonance at 900 MHz

“…In clinical imaging, the main challenge is still how to distinguish different characteristics of skin components such as semisolid glycolipids, hair root, oil-rich sebaceous glands and active epidermis viable layer with limited success using different clinical MRI techniques as listed in Table 1 [2][3][4][5][6][7][8][9][10][11][12].…”

“…These useful tools and several contributory factors such as very small dimensions of skin components in the range of 500-1500 μm, dependence of hair keratin, oil-and fat-rich components on magnetization transfer property, longer imaging pulse sequences, etc., are reviewed in Table 1. However, poor spatial resolution and accurate quantitative in vivo 1.5-T measurements of skin features still remain as unsolved problems due to the short T2 characteristics of skin tissues and the multiexponential nature of skin T2 behavior [3][4][5][6][13][14][15][16][17][18][19][20]. For quantitative MRI of skin tissue, better visualization of skin structures may be achieved by high-resolution multicontrast MRI approach at 900 MHz.…”

Botulinum toxin in the treatment of sweat-worsened foot problems in patients with epidermolysis bullosa simplex and pachyonychia congenita

“…In one case (PC 8), a painful callus was also investigated by magnetic resonance (MR) spectroscopic microimaging before and after Btx therapy with the intention of demonstrating a reduction of blistering and maceration below a hyperkeratotic skin surface. This type of MR microimaging is a relatively new technique to visualize skin morphology at a high resolution without chemical shift artifacts 14–16 . In a parallel experiment, three weight‐bearing areas (heel, forefoot and big toe) were investigated by manometry before and after therapy in order to assess the maximal tolerable pressure (in Newton, N) before the patient complained of maximum pain.…”