Mri Technique

The elbow typically is scanned with the patient in a supine position with the arm at the side. A surface coil is essential for obtaining high-quality images. Depending on the size of the patient and the size of the surface coil relative to the bore of the magnet, it may be necessary to scan the patient in a prone position with the arm extended overhead. In general, the prone position is less well tolerated and results in a greater number of motion-degraded studies. When the patient's elbow is scanned, it should be in a comfortable position to avoid motion artifact. The elbow typically is extended and the wrist is placed in a neutral position. Technologists have more difficulty positioning patients who cannot extend the elbow; therefore, they must take more time and skill to obtain optimal images. Taping a vitamin E capsule or other marker to the skin at the site of tenderness or at the site of a palpable mass helps to ensure that the area of interest has been included in the study, especially when no abnormalities are identified on the images.

Excellent images may be obtained with both midfield and high-field MR systems. Proton-density and T2-weighted images typically are obtained in the axial and sagittal planes using the spin-echo or fast spin-echo technique. T1-weighted and short TI inversion recovery (STIR) sequences usually are obtained in the coronal plane. Although the STIR sequence has a relatively poor signal-to-noise ratio because of the suppression of signal from fat, abnormalities are often more conspicuous due to the effects of additive T1 and T2 contrast.

The axial images, in general, should extend from the distal humeral metaphysis to the radial tuberosity. The common flexor and extensor origins from the medial and lateral humeral epicondyles and the biceps insertion on the radial tuberosity are routinely imaged with this coverage. This coverage usually is obtained with 3- or 4-mm-thick slices using a long time of repetition (TR) sequence. The coronal images are angled parallel to a line through the humeral epicondyles on the axial images. The sagittal images are angled perpendicular to a line through the humeral epicondyles on the axial images.

The field of view on the axial images should be as small as the signal of the surface coil and the size of the patient's elbow allow. To include more of the anatomy about the elbow, the field of view selected on the coronal and sagittal sequences is usually larger than the field of view on the axial images. This guideline is especially true when imaging a ruptured biceps tendon that may retract to the normal superior margin of coverage. The slice thickness, interslice gap, and TR may be increased on the axial sequences just as the field of view is increased on the coronal and sagittal sequences as long as the surface coil provides adequate signal to image the entire length of the abnormality.

Additional sequences may be added or substituted depending on the clinical problem that must be solved. T2*-weighted gradient-echo sequences provide useful supplemental information for identifying loose bodies within the elbow. In general, gradient-echo sequences should be avoided after elbow surgery because magnetic susceptibility artifacts associated with micrometallic debris may obscure the images and also may be mistaken for loose bodies. Fast spin-echo and fast STIR sequences may be substituted for conventional T2-weighted spin-echo and conventional STIR sequences if available; these newer sequences allow greater flexibility in imaging the elbow while continuing to provide information that is comparable with that of the conventional spin-echo and conventional STIR sequences. The speed of fast spin-echo sequences may be used to obtain higher-resolution T2-weighted images in the same amount of time as the conventional spin-echo sequences, or it simply may be used to increase the speed of the examination. The ability to shorten the examination with fast spin-echo has been useful when scanning claustrophobic patients or patients who become uncomfortable in the prone position with the arm overhead.

Fat suppression may be added to various pulse sequences to improve visualization of the hyaline articular cartilage. Avoidance of chemical shift artifact at the interface of cortical bone and fat-containing marrow permits a more accurate depiction of the overlying hyaline cartilage. T1-weighted images with fat suppression are useful whenever gadolinium is administered, either in travenously or directly into the elbow joint. Intravenous gadolinium may provide additional information in the assessment of neoplastic or inflammatory processes about the elbow. Articular injection of saline or dilute gadolinium may be useful in patients without a joint effusion to detect loose bodies, to determine if the capsule is disrupted, or to determine if an osteochondral fracture fragment is stable.

Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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