Low cost MRI of the paranasal sinuses

The use of automated tuning, automated MR protocol sequences, surface coils, and grouping of patients with similar examinations, patient throughput can be greatly accelerated for MRI scanning. These measures coupled with high volume scanning permit significant reductions in cost so that MRI can be performed at a price range equal to or less than plain films for some examinations. The ability of MRI to perform axial, sagittal and coronal scans with excellent tissue contrast raises the possibility of substituting MRI for sinus x-rays. Based on our preliminary experience we have the opinion that MR is equal to/or better than CT in this region. This preference is currently being investigated. Only the cost issue will be addressed in this report.     

Incudostapedial joint in health and disease.

The incudostapedial joint was studied in tomograms of 370 normal and 80 diseased middle ears. The Guillen view was found to be superior to the anteroposterior view in demonstrating this joint in normal middle ears (85% and 62% visualization, respectively). In the presence of disease, visualization was markedly reduced to 19%; this lack of visualization is a nonspecific finding since early cholesteatomas, chronic otitis media, and retraction pockets could not be differentiated radiologically. Nonvisualization of the incudostapedial joint in the Guillen view is a more objective indicator of middle ear disease than such terms as "indistinct of hazy" middle ear cavities.     

Laryngeal involvement in rheumatoid arthritis

Laryngeal involvement was evaluated in 45 patients with moderately severe rheumatoid arthritis (RA). RA duration and severity, prior laryngeal symptoms, and abnormalities detected by concurrent indirect laryngoscopy (IL) and computerized tomography (CT) were noted and correlated with changes of basilar interstitial fibrosis (BPF) found by chest radiograph. Thirty-two percent had abnormalities detected by IL, 54% had abnormalities by CT, and 36% had BPF on chest radiographs. Comparison of these groups revealed: only two symptoms (sore throat and difficulty during inspiration) were predictive of abnormalities detected by IL; no symptoms predicted abnormalities on CT; IL and CT may show abnormalities in a large percentage of RA patients even in the absence of symptoms; IL tends to detect mucosal and gross functional abnormalities while CT detects structural lesions; BPF shown on chest radiographs in RA patients does not appear to be correlated with cricoarytenoid arthritis as defined by IL and CT.     

Computed tomography of the parotid gland during contrast sialography.

By performing CT scanning during contrast sialography, tumors within the parotid gland can be shown and their configuration in relation to the remaining normal salivary gland and surrounding structures can be appreciated. This permits better evaluation of the relationship of the tumor to the facial nerve, possible extension of tumor beyond the gland, and benign versus malignant growth characteristics     

Solenoid surface coils in magnetic resonance imaging

A nonplanar solenoidal surface radiofrequency coil is used as a receiver with a conventional transmitter coil in a magnetic resonance imaging system. The improved signal-to-noise ratio, compared with that of conventional fixed saddle or solenoid receiver coils, permits higher resolution imaging and thinner image sections. In addition, the problem of signal dropoff that occurs in deep structures with planar and other noncircumferential surface coils is eliminated. Solenoid surface coils are particularly useful in imaging deep structures in anatomic regions that do not fit standard head and body coils, such as the neck, knees, and other smaller body parts.